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* [PATCH v3 0/2] add SPI controller driver for UniPhier SoCs
@ 2018-08-01  7:29 ` Keiji Hayashibara
  0 siblings, 0 replies; 14+ messages in thread
From: Keiji Hayashibara @ 2018-08-01  7:29 UTC (permalink / raw)
  To: broonie, robh+dt, mark.rutland, yamada.masahiro, linux-spi,
	linux-arm-kernel, devicetree
  Cc: masami.hiramatsu, jaswinder.singh, linux-kernel, hayashibara.keiji

This series adds support for SPI controller driver implemented on UniPhier SoCs.

Changes since v2:
- remove check code of clock divider in uniphier_spi_set_baudrate().
- change irq from struct variable to stack variable.
- other trivial change.

Keiji Hayashibara (1):
  spi: add SPI controller driver for UniPhier SoC

Kunihiko Hayashi (1):
  dt-bindings: spi: add DT bindings for UniPhier SPI controller

 .../devicetree/bindings/spi/spi-uniphier.txt       |  22 +
 drivers/spi/Kconfig                                |  13 +
 drivers/spi/Makefile                               |   1 +
 drivers/spi/spi-uniphier.c                         | 525 +++++++++++++++++++++
 4 files changed, 561 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/spi/spi-uniphier.txt
 create mode 100644 drivers/spi/spi-uniphier.c

-- 
2.7.4


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH v3 0/2] add SPI controller driver for UniPhier SoCs
@ 2018-08-01  7:29 ` Keiji Hayashibara
  0 siblings, 0 replies; 14+ messages in thread
From: Keiji Hayashibara @ 2018-08-01  7:29 UTC (permalink / raw)
  To: linux-arm-kernel

This series adds support for SPI controller driver implemented on UniPhier SoCs.

Changes since v2:
- remove check code of clock divider in uniphier_spi_set_baudrate().
- change irq from struct variable to stack variable.
- other trivial change.

Keiji Hayashibara (1):
  spi: add SPI controller driver for UniPhier SoC

Kunihiko Hayashi (1):
  dt-bindings: spi: add DT bindings for UniPhier SPI controller

 .../devicetree/bindings/spi/spi-uniphier.txt       |  22 +
 drivers/spi/Kconfig                                |  13 +
 drivers/spi/Makefile                               |   1 +
 drivers/spi/spi-uniphier.c                         | 525 +++++++++++++++++++++
 4 files changed, 561 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/spi/spi-uniphier.txt
 create mode 100644 drivers/spi/spi-uniphier.c

-- 
2.7.4

^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH v3 1/2] dt-bindings: spi: add DT bindings for UniPhier SPI controller
  2018-08-01  7:29 ` Keiji Hayashibara
@ 2018-08-01  7:29   ` Keiji Hayashibara
  -1 siblings, 0 replies; 14+ messages in thread
From: Keiji Hayashibara @ 2018-08-01  7:29 UTC (permalink / raw)
  To: broonie, robh+dt, mark.rutland, yamada.masahiro, linux-spi,
	linux-arm-kernel, devicetree
  Cc: masami.hiramatsu, jaswinder.singh, linux-kernel,
	hayashibara.keiji, Kunihiko Hayashi

From: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>

Add DT bindings for SPI controller implemented in UniPhier SoCs.

Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Keiji Hayashibara <hayashibara.keiji@socionext.com>
Reviewed-by: Rob Herring <robh@kernel.org>
---
 .../devicetree/bindings/spi/spi-uniphier.txt       | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/spi/spi-uniphier.txt

diff --git a/Documentation/devicetree/bindings/spi/spi-uniphier.txt b/Documentation/devicetree/bindings/spi/spi-uniphier.txt
new file mode 100644
index 0000000..504a4ec
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/spi-uniphier.txt
@@ -0,0 +1,22 @@
+Socionext UniPhier SPI controller driver
+
+UniPhier SoCs have SCSSI which supports SPI single channel.
+
+Required properties:
+ - compatible: should be "socionext,uniphier-scssi"
+ - reg: address and length of the spi master registers
+ - #address-cells: must be <1>, see spi-bus.txt
+ - #size-cells: must be <0>, see spi-bus.txt
+ - clocks: A phandle to the clock for the device.
+ - resets: A phandle to the reset control for the device.
+
+Example:
+
+spi0: spi@54006000 {
+	compatible = "socionext,uniphier-scssi";
+	reg = <0x54006000 0x100>;
+	#address-cells = <1>;
+	#size-cells = <0>;
+	clocks = <&peri_clk 11>;
+	resets = <&peri_rst 11>;
+};
-- 
2.7.4


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH v3 1/2] dt-bindings: spi: add DT bindings for UniPhier SPI controller
@ 2018-08-01  7:29   ` Keiji Hayashibara
  0 siblings, 0 replies; 14+ messages in thread
From: Keiji Hayashibara @ 2018-08-01  7:29 UTC (permalink / raw)
  To: linux-arm-kernel

From: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>

Add DT bindings for SPI controller implemented in UniPhier SoCs.

Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Keiji Hayashibara <hayashibara.keiji@socionext.com>
Reviewed-by: Rob Herring <robh@kernel.org>
---
 .../devicetree/bindings/spi/spi-uniphier.txt       | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/spi/spi-uniphier.txt

diff --git a/Documentation/devicetree/bindings/spi/spi-uniphier.txt b/Documentation/devicetree/bindings/spi/spi-uniphier.txt
new file mode 100644
index 0000000..504a4ec
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/spi-uniphier.txt
@@ -0,0 +1,22 @@
+Socionext UniPhier SPI controller driver
+
+UniPhier SoCs have SCSSI which supports SPI single channel.
+
+Required properties:
+ - compatible: should be "socionext,uniphier-scssi"
+ - reg: address and length of the spi master registers
+ - #address-cells: must be <1>, see spi-bus.txt
+ - #size-cells: must be <0>, see spi-bus.txt
+ - clocks: A phandle to the clock for the device.
+ - resets: A phandle to the reset control for the device.
+
+Example:
+
+spi0: spi at 54006000 {
+	compatible = "socionext,uniphier-scssi";
+	reg = <0x54006000 0x100>;
+	#address-cells = <1>;
+	#size-cells = <0>;
+	clocks = <&peri_clk 11>;
+	resets = <&peri_rst 11>;
+};
-- 
2.7.4

^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH v3 2/2] spi: add SPI controller driver for UniPhier SoC
  2018-08-01  7:29 ` Keiji Hayashibara
@ 2018-08-01  7:29   ` Keiji Hayashibara
  -1 siblings, 0 replies; 14+ messages in thread
From: Keiji Hayashibara @ 2018-08-01  7:29 UTC (permalink / raw)
  To: broonie, robh+dt, mark.rutland, yamada.masahiro, linux-spi,
	linux-arm-kernel, devicetree
  Cc: masami.hiramatsu, jaswinder.singh, linux-kernel,
	hayashibara.keiji, Kunihiko Hayashi

Add SPI controller driver implemented in Socionext UniPhier SoCs.

UniPhier SoCs have two types SPI controllers; SCSSI supports a
single channel, and MCSSI supports multiple channels.
This driver supports SCSSI only.

This controller has 32bit TX/RX FIFO with depth of eight entry,
and supports the SPI master mode only.

This commit is implemented in PIO transfer mode, not DMA transfer.

Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Keiji Hayashibara <hayashibara.keiji@socionext.com>
---
 drivers/spi/Kconfig        |  13 ++
 drivers/spi/Makefile       |   1 +
 drivers/spi/spi-uniphier.c | 525 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 539 insertions(+)
 create mode 100644 drivers/spi/spi-uniphier.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index ad5d68e..671d078 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -688,6 +688,19 @@ config SPI_TXX9
 	help
 	  SPI driver for Toshiba TXx9 MIPS SoCs
 
+config SPI_UNIPHIER
+	tristate "Socionext UniPhier SPI Controller"
+	depends on (ARCH_UNIPHIER || COMPILE_TEST) && OF
+	help
+	  This enables a driver for the Socionext UniPhier SoC SCSSI SPI controller.
+
+	  UniPhier SoCs have SCSSI and MCSSI SPI controllers.
+	  Every UniPhier SoC has SCSSI which supports single channel.
+	  Older UniPhier Pro4/Pro5 also has MCSSI which support multiple channels.
+	  This driver supports SCSSI only.
+
+	  If your SoC supports SCSSI, say Y here.
+
 config SPI_XCOMM
 	tristate "Analog Devices AD-FMCOMMS1-EBZ SPI-I2C-bridge driver"
 	depends on I2C
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index cb1f437..a90d559 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -101,6 +101,7 @@ spi-thunderx-objs			:= spi-cavium.o spi-cavium-thunderx.o
 obj-$(CONFIG_SPI_THUNDERX)		+= spi-thunderx.o
 obj-$(CONFIG_SPI_TOPCLIFF_PCH)		+= spi-topcliff-pch.o
 obj-$(CONFIG_SPI_TXX9)			+= spi-txx9.o
+obj-$(CONFIG_SPI_UNIPHIER)		+= spi-uniphier.o
 obj-$(CONFIG_SPI_XCOMM)		+= spi-xcomm.o
 obj-$(CONFIG_SPI_XILINX)		+= spi-xilinx.o
 obj-$(CONFIG_SPI_XLP)			+= spi-xlp.o
diff --git a/drivers/spi/spi-uniphier.c b/drivers/spi/spi-uniphier.c
new file mode 100644
index 0000000..0899854
--- /dev/null
+++ b/drivers/spi/spi-uniphier.c
@@ -0,0 +1,525 @@
+// SPDX-License-Identifier: GPL-2.0
+// spi-uniphier.c - Socionext UniPhier SPI controller driver
+// Copyright 2012      Panasonic Corporation
+// Copyright 2016-2018 Socionext Inc.
+
+#include <linux/kernel.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+
+#include <asm/unaligned.h>
+
+#define SSI_TIMEOUT_MS		2000
+#define SSI_MAX_CLK_DIVIDER	254
+#define SSI_MIN_CLK_DIVIDER	4
+
+struct uniphier_spi_priv {
+	void __iomem *base;
+	struct clk *clk;
+	struct spi_master *master;
+	struct completion xfer_done;
+
+	int error;
+	unsigned int tx_bytes;
+	unsigned int rx_bytes;
+	const u8 *tx_buf;
+	u8 *rx_buf;
+
+	bool is_save_param;
+	u8 bits_per_word;
+	u16 mode;
+	u32 speed_hz;
+};
+
+#define SSI_CTL			0x00
+#define   SSI_CTL_EN		BIT(0)
+
+#define SSI_CKS			0x04
+#define   SSI_CKS_CKRAT_MASK	GENMASK(7, 0)
+#define   SSI_CKS_CKPHS		BIT(14)
+#define   SSI_CKS_CKINIT	BIT(13)
+#define   SSI_CKS_CKDLY		BIT(12)
+
+#define SSI_TXWDS		0x08
+#define   SSI_TXWDS_WDLEN_MASK	GENMASK(13, 8)
+#define   SSI_TXWDS_TDTF_MASK	GENMASK(7, 6)
+#define   SSI_TXWDS_DTLEN_MASK	GENMASK(5, 0)
+
+#define SSI_RXWDS		0x0c
+#define   SSI_RXWDS_DTLEN_MASK	GENMASK(5, 0)
+
+#define SSI_FPS			0x10
+#define   SSI_FPS_FSPOL		BIT(15)
+#define   SSI_FPS_FSTRT		BIT(14)
+
+#define SSI_SR			0x14
+#define   SSI_SR_RNE		BIT(0)
+
+#define SSI_IE			0x18
+#define   SSI_IE_RCIE		BIT(3)
+#define   SSI_IE_RORIE		BIT(0)
+
+#define SSI_IS			0x1c
+#define   SSI_IS_RXRS		BIT(9)
+#define   SSI_IS_RCID		BIT(3)
+#define   SSI_IS_RORID		BIT(0)
+
+#define SSI_IC			0x1c
+#define   SSI_IC_TCIC		BIT(4)
+#define   SSI_IC_RCIC		BIT(3)
+#define   SSI_IC_RORIC		BIT(0)
+
+#define SSI_FC			0x20
+#define   SSI_FC_TXFFL		BIT(12)
+#define   SSI_FC_TXFTH_MASK	GENMASK(11, 8)
+#define   SSI_FC_RXFFL		BIT(4)
+#define   SSI_FC_RXFTH_MASK	GENMASK(3, 0)
+
+#define SSI_TXDR		0x24
+#define SSI_RXDR		0x24
+
+#define SSI_FIFO_DEPTH		8U
+
+static inline unsigned int bytes_per_word(unsigned int bits)
+{
+	return bits <= 8 ? 1 : (bits <= 16 ? 2 : 4);
+}
+
+static inline void uniphier_spi_irq_enable(struct spi_device *spi, u32 mask)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_IE);
+	val |= mask;
+	writel(val, priv->base + SSI_IE);
+}
+
+static inline void uniphier_spi_irq_disable(struct spi_device *spi, u32 mask)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_IE);
+	val &= ~mask;
+	writel(val, priv->base + SSI_IE);
+}
+
+static void uniphier_spi_set_mode(struct spi_device *spi)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val1, val2;
+
+	/*
+	 * clock setting
+	 * CKPHS    capture timing. 0:rising edge, 1:falling edge
+	 * CKINIT   clock initial level. 0:low, 1:high
+	 * CKDLY    clock delay. 0:no delay, 1:delay depending on FSTRT
+	 *          (FSTRT=0: 1 clock, FSTRT=1: 0.5 clock)
+	 *
+	 * frame setting
+	 * FSPOL    frame signal porarity. 0: low, 1: high
+	 * FSTRT    start frame timing
+	 *          0: rising edge of clock, 1: falling edge of clock
+	 */
+	switch (spi->mode & (SPI_CPOL | SPI_CPHA)) {
+	case SPI_MODE_0:
+		/* CKPHS=1, CKINIT=0, CKDLY=1, FSTRT=0 */
+		val1 = SSI_CKS_CKPHS | SSI_CKS_CKDLY;
+		val2 = 0;
+		break;
+	case SPI_MODE_1:
+		/* CKPHS=0, CKINIT=0, CKDLY=0, FSTRT=1 */
+		val1 = 0;
+		val2 = SSI_FPS_FSTRT;
+		break;
+	case SPI_MODE_2:
+		/* CKPHS=0, CKINIT=1, CKDLY=1, FSTRT=1 */
+		val1 = SSI_CKS_CKINIT | SSI_CKS_CKDLY;
+		val2 = SSI_FPS_FSTRT;
+		break;
+	case SPI_MODE_3:
+		/* CKPHS=1, CKINIT=1, CKDLY=0, FSTRT=0 */
+		val1 = SSI_CKS_CKPHS | SSI_CKS_CKINIT;
+		val2 = 0;
+		break;
+	}
+
+	if (!(spi->mode & SPI_CS_HIGH))
+		val2 |= SSI_FPS_FSPOL;
+
+	writel(val1, priv->base + SSI_CKS);
+	writel(val2, priv->base + SSI_FPS);
+
+	val1 = 0;
+	if (spi->mode & SPI_LSB_FIRST)
+		val1 |= FIELD_PREP(SSI_TXWDS_TDTF_MASK, 1);
+	writel(val1, priv->base + SSI_TXWDS);
+	writel(val1, priv->base + SSI_RXWDS);
+}
+
+static void uniphier_spi_set_transfer_size(struct spi_device *spi, int size)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_TXWDS);
+	val &= ~(SSI_TXWDS_WDLEN_MASK | SSI_TXWDS_DTLEN_MASK);
+	val |= FIELD_PREP(SSI_TXWDS_WDLEN_MASK, size);
+	val |= FIELD_PREP(SSI_TXWDS_DTLEN_MASK, size);
+	writel(val, priv->base + SSI_TXWDS);
+
+	val = readl(priv->base + SSI_RXWDS);
+	val &= ~SSI_RXWDS_DTLEN_MASK;
+	val |= FIELD_PREP(SSI_RXWDS_DTLEN_MASK, size);
+	writel(val, priv->base + SSI_RXWDS);
+}
+
+static void uniphier_spi_set_baudrate(struct spi_device *spi,
+				      unsigned int speed)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val, ckdiv;
+
+	/*
+	 * the supported rates are even numbers from 4 to 254. (4,6,8...254)
+	 * round up as we look for equal or less speed
+	 */
+	ckdiv = DIV_ROUND_UP(clk_get_rate(priv->clk), speed);
+	ckdiv = round_up(ckdiv, 2);
+
+	val = readl(priv->base + SSI_CKS);
+	val &= ~SSI_CKS_CKRAT_MASK;
+	val |= ckdiv & SSI_CKS_CKRAT_MASK;
+	writel(val, priv->base + SSI_CKS);
+}
+
+static void uniphier_spi_setup_transfer(struct spi_device *spi,
+				       struct spi_transfer *t)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	priv->error = 0;
+	priv->tx_buf = t->tx_buf;
+	priv->rx_buf = t->rx_buf;
+	priv->tx_bytes = priv->rx_bytes = t->len;
+
+	if (!priv->is_save_param || priv->mode != spi->mode) {
+		uniphier_spi_set_mode(spi);
+		priv->mode = spi->mode;
+	}
+
+	if (!priv->is_save_param || priv->bits_per_word != t->bits_per_word) {
+		uniphier_spi_set_transfer_size(spi, t->bits_per_word);
+		priv->bits_per_word = t->bits_per_word;
+	}
+
+	if (!priv->is_save_param || priv->speed_hz != t->speed_hz) {
+		uniphier_spi_set_baudrate(spi, t->speed_hz);
+		priv->speed_hz = t->speed_hz;
+	}
+
+	if (!priv->is_save_param)
+		priv->is_save_param = true;
+
+	/* reset FIFOs */
+	val = SSI_FC_TXFFL | SSI_FC_RXFFL;
+	writel(val, priv->base + SSI_FC);
+}
+
+static void uniphier_spi_send(struct uniphier_spi_priv *priv)
+{
+	int wsize;
+	u32 val = 0;
+
+	wsize = min(bytes_per_word(priv->bits_per_word), priv->tx_bytes);
+	priv->tx_bytes -= wsize;
+
+	if (priv->tx_buf) {
+		switch (wsize) {
+		case 1:
+			val = *priv->tx_buf;
+			break;
+		case 2:
+			val = get_unaligned_le16(priv->tx_buf);
+			break;
+		case 4:
+			val = get_unaligned_le32(priv->tx_buf);
+			break;
+		}
+
+		priv->tx_buf += wsize;
+	}
+
+	writel(val, priv->base + SSI_TXDR);
+}
+
+static void uniphier_spi_recv(struct uniphier_spi_priv *priv)
+{
+	int rsize;
+	u32 val;
+
+	rsize = min(bytes_per_word(priv->bits_per_word), priv->rx_bytes);
+	priv->rx_bytes -= rsize;
+
+	val = readl(priv->base + SSI_RXDR);
+
+	if (priv->rx_buf) {
+		switch (rsize) {
+		case 1:
+			*priv->rx_buf = val;
+			break;
+		case 2:
+			put_unaligned_le16(val, priv->rx_buf);
+			break;
+		case 4:
+			put_unaligned_le32(val, priv->rx_buf);
+			break;
+		}
+
+		priv->rx_buf += rsize;
+	}
+}
+
+static void uniphier_spi_fill_tx_fifo(struct uniphier_spi_priv *priv)
+{
+	unsigned int tx_count;
+	u32 val;
+
+	tx_count = DIV_ROUND_UP(priv->tx_bytes,
+				bytes_per_word(priv->bits_per_word));
+	tx_count = min(tx_count, SSI_FIFO_DEPTH);
+
+	/* set fifo threshold */
+	val = readl(priv->base + SSI_FC);
+	val &= ~(SSI_FC_TXFTH_MASK | SSI_FC_RXFTH_MASK);
+	val |= FIELD_PREP(SSI_FC_TXFTH_MASK, tx_count);
+	val |= FIELD_PREP(SSI_FC_RXFTH_MASK, tx_count);
+	writel(val, priv->base + SSI_FC);
+
+	while (tx_count--)
+		uniphier_spi_send(priv);
+}
+
+static void uniphier_spi_set_cs(struct spi_device *spi, bool enable)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_FPS);
+
+	if (enable)
+		val |= SSI_FPS_FSPOL;
+	else
+		val &= ~SSI_FPS_FSPOL;
+
+	writel(val, priv->base + SSI_FPS);
+}
+
+static int uniphier_spi_transfer_one(struct spi_master *master,
+				     struct spi_device *spi,
+				     struct spi_transfer *t)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+	int status;
+
+	uniphier_spi_setup_transfer(spi, t);
+
+	reinit_completion(&priv->xfer_done);
+
+	uniphier_spi_fill_tx_fifo(priv);
+
+	uniphier_spi_irq_enable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
+
+	status = wait_for_completion_timeout(&priv->xfer_done,
+					     msecs_to_jiffies(SSI_TIMEOUT_MS));
+
+	uniphier_spi_irq_disable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
+
+	if (status < 0)
+		return status;
+
+	return priv->error;
+}
+
+static int uniphier_spi_prepare_transfer_hardware(struct spi_master *master)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+
+	writel(SSI_CTL_EN, priv->base + SSI_CTL);
+
+	return 0;
+}
+
+static int uniphier_spi_unprepare_transfer_hardware(struct spi_master *master)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+
+	writel(0, priv->base + SSI_CTL);
+
+	return 0;
+}
+
+static irqreturn_t uniphier_spi_handler(int irq, void *dev_id)
+{
+	struct uniphier_spi_priv *priv = dev_id;
+	u32 val, stat;
+
+	stat = readl(priv->base + SSI_IS);
+	val = SSI_IC_TCIC | SSI_IC_RCIC | SSI_IC_RORIC;
+	writel(val, priv->base + SSI_IC);
+
+	/* rx fifo overrun */
+	if (stat & SSI_IS_RORID) {
+		priv->error = -EIO;
+		goto done;
+	}
+
+	/* rx complete */
+	if ((stat & SSI_IS_RCID) && (stat & SSI_IS_RXRS)) {
+		while ((readl(priv->base + SSI_SR) & SSI_SR_RNE) &&
+				(priv->rx_bytes - priv->tx_bytes) > 0)
+			uniphier_spi_recv(priv);
+
+		if ((readl(priv->base + SSI_SR) & SSI_SR_RNE) ||
+				(priv->rx_bytes != priv->tx_bytes)) {
+			priv->error = -EIO;
+			goto done;
+		} else if (priv->rx_bytes == 0)
+			goto done;
+
+		/* next tx transfer */
+		uniphier_spi_fill_tx_fifo(priv);
+
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
+
+done:
+	complete(&priv->xfer_done);
+	return IRQ_HANDLED;
+}
+
+static int uniphier_spi_probe(struct platform_device *pdev)
+{
+	struct uniphier_spi_priv *priv;
+	struct spi_master *master;
+	struct resource *res;
+	unsigned long clk_rate;
+	int irq;
+	int ret;
+
+	master = spi_alloc_master(&pdev->dev, sizeof(*priv));
+	if (!master)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, master);
+
+	priv = spi_master_get_devdata(master);
+	priv->master = master;
+	priv->is_save_param = false;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(priv->base)) {
+		ret = PTR_ERR(priv->base);
+		goto out_master_put;
+	}
+
+	priv->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(priv->clk)) {
+		dev_err(&pdev->dev, "failed to get clock\n");
+		ret = PTR_ERR(priv->clk);
+		goto out_master_put;
+	}
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret)
+		goto out_master_put;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(&pdev->dev, "failed to get IRQ\n");
+		ret = irq;
+		goto out_disable_clk;
+	}
+
+	ret = devm_request_irq(&pdev->dev, irq, uniphier_spi_handler,
+			       0, "uniphier-spi", priv);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to request IRQ\n");
+		goto out_disable_clk;
+	}
+
+	init_completion(&priv->xfer_done);
+
+	clk_rate = clk_get_rate(priv->clk);
+
+	master->max_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MIN_CLK_DIVIDER);
+	master->min_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MAX_CLK_DIVIDER);
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
+	master->dev.of_node = pdev->dev.of_node;
+	master->bus_num = pdev->id;
+	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
+
+	master->set_cs = uniphier_spi_set_cs;
+	master->transfer_one = uniphier_spi_transfer_one;
+	master->prepare_transfer_hardware
+				= uniphier_spi_prepare_transfer_hardware;
+	master->unprepare_transfer_hardware
+				= uniphier_spi_unprepare_transfer_hardware;
+	master->num_chipselect = 1;
+
+	ret = devm_spi_register_master(&pdev->dev, master);
+	if (ret)
+		goto out_disable_clk;
+
+	return 0;
+
+out_disable_clk:
+	clk_disable_unprepare(priv->clk);
+
+out_master_put:
+	spi_master_put(master);
+	return ret;
+}
+
+static int uniphier_spi_remove(struct platform_device *pdev)
+{
+	struct uniphier_spi_priv *priv = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(priv->clk);
+
+	return 0;
+}
+
+static const struct of_device_id uniphier_spi_match[] = {
+	{ .compatible = "socionext,uniphier-scssi" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, uniphier_spi_match);
+
+static struct platform_driver uniphier_spi_driver = {
+	.probe = uniphier_spi_probe,
+	.remove = uniphier_spi_remove,
+	.driver = {
+		.name = "uniphier-spi",
+		.of_match_table = uniphier_spi_match,
+	},
+};
+module_platform_driver(uniphier_spi_driver);
+
+MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
+MODULE_AUTHOR("Keiji Hayashibara <hayashibara.keiji@socionext.com>");
+MODULE_DESCRIPTION("Socionext UniPhier SPI controller driver");
+MODULE_LICENSE("GPL v2");
-- 
2.7.4


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH v3 2/2] spi: add SPI controller driver for UniPhier SoC
@ 2018-08-01  7:29   ` Keiji Hayashibara
  0 siblings, 0 replies; 14+ messages in thread
From: Keiji Hayashibara @ 2018-08-01  7:29 UTC (permalink / raw)
  To: linux-arm-kernel

Add SPI controller driver implemented in Socionext UniPhier SoCs.

UniPhier SoCs have two types SPI controllers; SCSSI supports a
single channel, and MCSSI supports multiple channels.
This driver supports SCSSI only.

This controller has 32bit TX/RX FIFO with depth of eight entry,
and supports the SPI master mode only.

This commit is implemented in PIO transfer mode, not DMA transfer.

Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Keiji Hayashibara <hayashibara.keiji@socionext.com>
---
 drivers/spi/Kconfig        |  13 ++
 drivers/spi/Makefile       |   1 +
 drivers/spi/spi-uniphier.c | 525 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 539 insertions(+)
 create mode 100644 drivers/spi/spi-uniphier.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index ad5d68e..671d078 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -688,6 +688,19 @@ config SPI_TXX9
 	help
 	  SPI driver for Toshiba TXx9 MIPS SoCs
 
+config SPI_UNIPHIER
+	tristate "Socionext UniPhier SPI Controller"
+	depends on (ARCH_UNIPHIER || COMPILE_TEST) && OF
+	help
+	  This enables a driver for the Socionext UniPhier SoC SCSSI SPI controller.
+
+	  UniPhier SoCs have SCSSI and MCSSI SPI controllers.
+	  Every UniPhier SoC has SCSSI which supports single channel.
+	  Older UniPhier Pro4/Pro5 also has MCSSI which support multiple channels.
+	  This driver supports SCSSI only.
+
+	  If your SoC supports SCSSI, say Y here.
+
 config SPI_XCOMM
 	tristate "Analog Devices AD-FMCOMMS1-EBZ SPI-I2C-bridge driver"
 	depends on I2C
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index cb1f437..a90d559 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -101,6 +101,7 @@ spi-thunderx-objs			:= spi-cavium.o spi-cavium-thunderx.o
 obj-$(CONFIG_SPI_THUNDERX)		+= spi-thunderx.o
 obj-$(CONFIG_SPI_TOPCLIFF_PCH)		+= spi-topcliff-pch.o
 obj-$(CONFIG_SPI_TXX9)			+= spi-txx9.o
+obj-$(CONFIG_SPI_UNIPHIER)		+= spi-uniphier.o
 obj-$(CONFIG_SPI_XCOMM)		+= spi-xcomm.o
 obj-$(CONFIG_SPI_XILINX)		+= spi-xilinx.o
 obj-$(CONFIG_SPI_XLP)			+= spi-xlp.o
diff --git a/drivers/spi/spi-uniphier.c b/drivers/spi/spi-uniphier.c
new file mode 100644
index 0000000..0899854
--- /dev/null
+++ b/drivers/spi/spi-uniphier.c
@@ -0,0 +1,525 @@
+// SPDX-License-Identifier: GPL-2.0
+// spi-uniphier.c - Socionext UniPhier SPI controller driver
+// Copyright 2012      Panasonic Corporation
+// Copyright 2016-2018 Socionext Inc.
+
+#include <linux/kernel.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+
+#include <asm/unaligned.h>
+
+#define SSI_TIMEOUT_MS		2000
+#define SSI_MAX_CLK_DIVIDER	254
+#define SSI_MIN_CLK_DIVIDER	4
+
+struct uniphier_spi_priv {
+	void __iomem *base;
+	struct clk *clk;
+	struct spi_master *master;
+	struct completion xfer_done;
+
+	int error;
+	unsigned int tx_bytes;
+	unsigned int rx_bytes;
+	const u8 *tx_buf;
+	u8 *rx_buf;
+
+	bool is_save_param;
+	u8 bits_per_word;
+	u16 mode;
+	u32 speed_hz;
+};
+
+#define SSI_CTL			0x00
+#define   SSI_CTL_EN		BIT(0)
+
+#define SSI_CKS			0x04
+#define   SSI_CKS_CKRAT_MASK	GENMASK(7, 0)
+#define   SSI_CKS_CKPHS		BIT(14)
+#define   SSI_CKS_CKINIT	BIT(13)
+#define   SSI_CKS_CKDLY		BIT(12)
+
+#define SSI_TXWDS		0x08
+#define   SSI_TXWDS_WDLEN_MASK	GENMASK(13, 8)
+#define   SSI_TXWDS_TDTF_MASK	GENMASK(7, 6)
+#define   SSI_TXWDS_DTLEN_MASK	GENMASK(5, 0)
+
+#define SSI_RXWDS		0x0c
+#define   SSI_RXWDS_DTLEN_MASK	GENMASK(5, 0)
+
+#define SSI_FPS			0x10
+#define   SSI_FPS_FSPOL		BIT(15)
+#define   SSI_FPS_FSTRT		BIT(14)
+
+#define SSI_SR			0x14
+#define   SSI_SR_RNE		BIT(0)
+
+#define SSI_IE			0x18
+#define   SSI_IE_RCIE		BIT(3)
+#define   SSI_IE_RORIE		BIT(0)
+
+#define SSI_IS			0x1c
+#define   SSI_IS_RXRS		BIT(9)
+#define   SSI_IS_RCID		BIT(3)
+#define   SSI_IS_RORID		BIT(0)
+
+#define SSI_IC			0x1c
+#define   SSI_IC_TCIC		BIT(4)
+#define   SSI_IC_RCIC		BIT(3)
+#define   SSI_IC_RORIC		BIT(0)
+
+#define SSI_FC			0x20
+#define   SSI_FC_TXFFL		BIT(12)
+#define   SSI_FC_TXFTH_MASK	GENMASK(11, 8)
+#define   SSI_FC_RXFFL		BIT(4)
+#define   SSI_FC_RXFTH_MASK	GENMASK(3, 0)
+
+#define SSI_TXDR		0x24
+#define SSI_RXDR		0x24
+
+#define SSI_FIFO_DEPTH		8U
+
+static inline unsigned int bytes_per_word(unsigned int bits)
+{
+	return bits <= 8 ? 1 : (bits <= 16 ? 2 : 4);
+}
+
+static inline void uniphier_spi_irq_enable(struct spi_device *spi, u32 mask)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_IE);
+	val |= mask;
+	writel(val, priv->base + SSI_IE);
+}
+
+static inline void uniphier_spi_irq_disable(struct spi_device *spi, u32 mask)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_IE);
+	val &= ~mask;
+	writel(val, priv->base + SSI_IE);
+}
+
+static void uniphier_spi_set_mode(struct spi_device *spi)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val1, val2;
+
+	/*
+	 * clock setting
+	 * CKPHS    capture timing. 0:rising edge, 1:falling edge
+	 * CKINIT   clock initial level. 0:low, 1:high
+	 * CKDLY    clock delay. 0:no delay, 1:delay depending on FSTRT
+	 *          (FSTRT=0: 1 clock, FSTRT=1: 0.5 clock)
+	 *
+	 * frame setting
+	 * FSPOL    frame signal porarity. 0: low, 1: high
+	 * FSTRT    start frame timing
+	 *          0: rising edge of clock, 1: falling edge of clock
+	 */
+	switch (spi->mode & (SPI_CPOL | SPI_CPHA)) {
+	case SPI_MODE_0:
+		/* CKPHS=1, CKINIT=0, CKDLY=1, FSTRT=0 */
+		val1 = SSI_CKS_CKPHS | SSI_CKS_CKDLY;
+		val2 = 0;
+		break;
+	case SPI_MODE_1:
+		/* CKPHS=0, CKINIT=0, CKDLY=0, FSTRT=1 */
+		val1 = 0;
+		val2 = SSI_FPS_FSTRT;
+		break;
+	case SPI_MODE_2:
+		/* CKPHS=0, CKINIT=1, CKDLY=1, FSTRT=1 */
+		val1 = SSI_CKS_CKINIT | SSI_CKS_CKDLY;
+		val2 = SSI_FPS_FSTRT;
+		break;
+	case SPI_MODE_3:
+		/* CKPHS=1, CKINIT=1, CKDLY=0, FSTRT=0 */
+		val1 = SSI_CKS_CKPHS | SSI_CKS_CKINIT;
+		val2 = 0;
+		break;
+	}
+
+	if (!(spi->mode & SPI_CS_HIGH))
+		val2 |= SSI_FPS_FSPOL;
+
+	writel(val1, priv->base + SSI_CKS);
+	writel(val2, priv->base + SSI_FPS);
+
+	val1 = 0;
+	if (spi->mode & SPI_LSB_FIRST)
+		val1 |= FIELD_PREP(SSI_TXWDS_TDTF_MASK, 1);
+	writel(val1, priv->base + SSI_TXWDS);
+	writel(val1, priv->base + SSI_RXWDS);
+}
+
+static void uniphier_spi_set_transfer_size(struct spi_device *spi, int size)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_TXWDS);
+	val &= ~(SSI_TXWDS_WDLEN_MASK | SSI_TXWDS_DTLEN_MASK);
+	val |= FIELD_PREP(SSI_TXWDS_WDLEN_MASK, size);
+	val |= FIELD_PREP(SSI_TXWDS_DTLEN_MASK, size);
+	writel(val, priv->base + SSI_TXWDS);
+
+	val = readl(priv->base + SSI_RXWDS);
+	val &= ~SSI_RXWDS_DTLEN_MASK;
+	val |= FIELD_PREP(SSI_RXWDS_DTLEN_MASK, size);
+	writel(val, priv->base + SSI_RXWDS);
+}
+
+static void uniphier_spi_set_baudrate(struct spi_device *spi,
+				      unsigned int speed)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val, ckdiv;
+
+	/*
+	 * the supported rates are even numbers from 4 to 254. (4,6,8...254)
+	 * round up as we look for equal or less speed
+	 */
+	ckdiv = DIV_ROUND_UP(clk_get_rate(priv->clk), speed);
+	ckdiv = round_up(ckdiv, 2);
+
+	val = readl(priv->base + SSI_CKS);
+	val &= ~SSI_CKS_CKRAT_MASK;
+	val |= ckdiv & SSI_CKS_CKRAT_MASK;
+	writel(val, priv->base + SSI_CKS);
+}
+
+static void uniphier_spi_setup_transfer(struct spi_device *spi,
+				       struct spi_transfer *t)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	priv->error = 0;
+	priv->tx_buf = t->tx_buf;
+	priv->rx_buf = t->rx_buf;
+	priv->tx_bytes = priv->rx_bytes = t->len;
+
+	if (!priv->is_save_param || priv->mode != spi->mode) {
+		uniphier_spi_set_mode(spi);
+		priv->mode = spi->mode;
+	}
+
+	if (!priv->is_save_param || priv->bits_per_word != t->bits_per_word) {
+		uniphier_spi_set_transfer_size(spi, t->bits_per_word);
+		priv->bits_per_word = t->bits_per_word;
+	}
+
+	if (!priv->is_save_param || priv->speed_hz != t->speed_hz) {
+		uniphier_spi_set_baudrate(spi, t->speed_hz);
+		priv->speed_hz = t->speed_hz;
+	}
+
+	if (!priv->is_save_param)
+		priv->is_save_param = true;
+
+	/* reset FIFOs */
+	val = SSI_FC_TXFFL | SSI_FC_RXFFL;
+	writel(val, priv->base + SSI_FC);
+}
+
+static void uniphier_spi_send(struct uniphier_spi_priv *priv)
+{
+	int wsize;
+	u32 val = 0;
+
+	wsize = min(bytes_per_word(priv->bits_per_word), priv->tx_bytes);
+	priv->tx_bytes -= wsize;
+
+	if (priv->tx_buf) {
+		switch (wsize) {
+		case 1:
+			val = *priv->tx_buf;
+			break;
+		case 2:
+			val = get_unaligned_le16(priv->tx_buf);
+			break;
+		case 4:
+			val = get_unaligned_le32(priv->tx_buf);
+			break;
+		}
+
+		priv->tx_buf += wsize;
+	}
+
+	writel(val, priv->base + SSI_TXDR);
+}
+
+static void uniphier_spi_recv(struct uniphier_spi_priv *priv)
+{
+	int rsize;
+	u32 val;
+
+	rsize = min(bytes_per_word(priv->bits_per_word), priv->rx_bytes);
+	priv->rx_bytes -= rsize;
+
+	val = readl(priv->base + SSI_RXDR);
+
+	if (priv->rx_buf) {
+		switch (rsize) {
+		case 1:
+			*priv->rx_buf = val;
+			break;
+		case 2:
+			put_unaligned_le16(val, priv->rx_buf);
+			break;
+		case 4:
+			put_unaligned_le32(val, priv->rx_buf);
+			break;
+		}
+
+		priv->rx_buf += rsize;
+	}
+}
+
+static void uniphier_spi_fill_tx_fifo(struct uniphier_spi_priv *priv)
+{
+	unsigned int tx_count;
+	u32 val;
+
+	tx_count = DIV_ROUND_UP(priv->tx_bytes,
+				bytes_per_word(priv->bits_per_word));
+	tx_count = min(tx_count, SSI_FIFO_DEPTH);
+
+	/* set fifo threshold */
+	val = readl(priv->base + SSI_FC);
+	val &= ~(SSI_FC_TXFTH_MASK | SSI_FC_RXFTH_MASK);
+	val |= FIELD_PREP(SSI_FC_TXFTH_MASK, tx_count);
+	val |= FIELD_PREP(SSI_FC_RXFTH_MASK, tx_count);
+	writel(val, priv->base + SSI_FC);
+
+	while (tx_count--)
+		uniphier_spi_send(priv);
+}
+
+static void uniphier_spi_set_cs(struct spi_device *spi, bool enable)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_FPS);
+
+	if (enable)
+		val |= SSI_FPS_FSPOL;
+	else
+		val &= ~SSI_FPS_FSPOL;
+
+	writel(val, priv->base + SSI_FPS);
+}
+
+static int uniphier_spi_transfer_one(struct spi_master *master,
+				     struct spi_device *spi,
+				     struct spi_transfer *t)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+	int status;
+
+	uniphier_spi_setup_transfer(spi, t);
+
+	reinit_completion(&priv->xfer_done);
+
+	uniphier_spi_fill_tx_fifo(priv);
+
+	uniphier_spi_irq_enable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
+
+	status = wait_for_completion_timeout(&priv->xfer_done,
+					     msecs_to_jiffies(SSI_TIMEOUT_MS));
+
+	uniphier_spi_irq_disable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
+
+	if (status < 0)
+		return status;
+
+	return priv->error;
+}
+
+static int uniphier_spi_prepare_transfer_hardware(struct spi_master *master)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+
+	writel(SSI_CTL_EN, priv->base + SSI_CTL);
+
+	return 0;
+}
+
+static int uniphier_spi_unprepare_transfer_hardware(struct spi_master *master)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+
+	writel(0, priv->base + SSI_CTL);
+
+	return 0;
+}
+
+static irqreturn_t uniphier_spi_handler(int irq, void *dev_id)
+{
+	struct uniphier_spi_priv *priv = dev_id;
+	u32 val, stat;
+
+	stat = readl(priv->base + SSI_IS);
+	val = SSI_IC_TCIC | SSI_IC_RCIC | SSI_IC_RORIC;
+	writel(val, priv->base + SSI_IC);
+
+	/* rx fifo overrun */
+	if (stat & SSI_IS_RORID) {
+		priv->error = -EIO;
+		goto done;
+	}
+
+	/* rx complete */
+	if ((stat & SSI_IS_RCID) && (stat & SSI_IS_RXRS)) {
+		while ((readl(priv->base + SSI_SR) & SSI_SR_RNE) &&
+				(priv->rx_bytes - priv->tx_bytes) > 0)
+			uniphier_spi_recv(priv);
+
+		if ((readl(priv->base + SSI_SR) & SSI_SR_RNE) ||
+				(priv->rx_bytes != priv->tx_bytes)) {
+			priv->error = -EIO;
+			goto done;
+		} else if (priv->rx_bytes == 0)
+			goto done;
+
+		/* next tx transfer */
+		uniphier_spi_fill_tx_fifo(priv);
+
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
+
+done:
+	complete(&priv->xfer_done);
+	return IRQ_HANDLED;
+}
+
+static int uniphier_spi_probe(struct platform_device *pdev)
+{
+	struct uniphier_spi_priv *priv;
+	struct spi_master *master;
+	struct resource *res;
+	unsigned long clk_rate;
+	int irq;
+	int ret;
+
+	master = spi_alloc_master(&pdev->dev, sizeof(*priv));
+	if (!master)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, master);
+
+	priv = spi_master_get_devdata(master);
+	priv->master = master;
+	priv->is_save_param = false;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(priv->base)) {
+		ret = PTR_ERR(priv->base);
+		goto out_master_put;
+	}
+
+	priv->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(priv->clk)) {
+		dev_err(&pdev->dev, "failed to get clock\n");
+		ret = PTR_ERR(priv->clk);
+		goto out_master_put;
+	}
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret)
+		goto out_master_put;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(&pdev->dev, "failed to get IRQ\n");
+		ret = irq;
+		goto out_disable_clk;
+	}
+
+	ret = devm_request_irq(&pdev->dev, irq, uniphier_spi_handler,
+			       0, "uniphier-spi", priv);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to request IRQ\n");
+		goto out_disable_clk;
+	}
+
+	init_completion(&priv->xfer_done);
+
+	clk_rate = clk_get_rate(priv->clk);
+
+	master->max_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MIN_CLK_DIVIDER);
+	master->min_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MAX_CLK_DIVIDER);
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
+	master->dev.of_node = pdev->dev.of_node;
+	master->bus_num = pdev->id;
+	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
+
+	master->set_cs = uniphier_spi_set_cs;
+	master->transfer_one = uniphier_spi_transfer_one;
+	master->prepare_transfer_hardware
+				= uniphier_spi_prepare_transfer_hardware;
+	master->unprepare_transfer_hardware
+				= uniphier_spi_unprepare_transfer_hardware;
+	master->num_chipselect = 1;
+
+	ret = devm_spi_register_master(&pdev->dev, master);
+	if (ret)
+		goto out_disable_clk;
+
+	return 0;
+
+out_disable_clk:
+	clk_disable_unprepare(priv->clk);
+
+out_master_put:
+	spi_master_put(master);
+	return ret;
+}
+
+static int uniphier_spi_remove(struct platform_device *pdev)
+{
+	struct uniphier_spi_priv *priv = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(priv->clk);
+
+	return 0;
+}
+
+static const struct of_device_id uniphier_spi_match[] = {
+	{ .compatible = "socionext,uniphier-scssi" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, uniphier_spi_match);
+
+static struct platform_driver uniphier_spi_driver = {
+	.probe = uniphier_spi_probe,
+	.remove = uniphier_spi_remove,
+	.driver = {
+		.name = "uniphier-spi",
+		.of_match_table = uniphier_spi_match,
+	},
+};
+module_platform_driver(uniphier_spi_driver);
+
+MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
+MODULE_AUTHOR("Keiji Hayashibara <hayashibara.keiji@socionext.com>");
+MODULE_DESCRIPTION("Socionext UniPhier SPI controller driver");
+MODULE_LICENSE("GPL v2");
-- 
2.7.4

^ permalink raw reply related	[flat|nested] 14+ messages in thread

* Re: [PATCH v3 2/2] spi: add SPI controller driver for UniPhier SoC
  2018-08-01  7:29   ` Keiji Hayashibara
@ 2018-08-01 10:20     ` Andy Shevchenko
  -1 siblings, 0 replies; 14+ messages in thread
From: Andy Shevchenko @ 2018-08-01 10:20 UTC (permalink / raw)
  To: Keiji Hayashibara
  Cc: Mark Brown, Rob Herring, Mark Rutland, Masahiro Yamada,
	linux-spi, linux-arm Mailing List, devicetree, Masami Hiramatsu,
	Jassi Brar, Linux Kernel Mailing List, Kunihiko Hayashi

On Wed, Aug 1, 2018 at 10:29 AM, Keiji Hayashibara
<hayashibara.keiji@socionext.com> wrote:
> Add SPI controller driver implemented in Socionext UniPhier SoCs.
>
> UniPhier SoCs have two types SPI controllers; SCSSI supports a
> single channel, and MCSSI supports multiple channels.
> This driver supports SCSSI only.
>
> This controller has 32bit TX/RX FIFO with depth of eight entry,
> and supports the SPI master mode only.
>
> This commit is implemented in PIO transfer mode, not DMA transfer.
>

One comment below, otherwise FWIW,
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>


> Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
> Signed-off-by: Keiji Hayashibara <hayashibara.keiji@socionext.com>
> ---
>  drivers/spi/Kconfig        |  13 ++
>  drivers/spi/Makefile       |   1 +
>  drivers/spi/spi-uniphier.c | 525 +++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 539 insertions(+)
>  create mode 100644 drivers/spi/spi-uniphier.c
>
> diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
> index ad5d68e..671d078 100644
> --- a/drivers/spi/Kconfig
> +++ b/drivers/spi/Kconfig
> @@ -688,6 +688,19 @@ config SPI_TXX9
>         help
>           SPI driver for Toshiba TXx9 MIPS SoCs
>
> +config SPI_UNIPHIER
> +       tristate "Socionext UniPhier SPI Controller"
> +       depends on (ARCH_UNIPHIER || COMPILE_TEST) && OF
> +       help
> +         This enables a driver for the Socionext UniPhier SoC SCSSI SPI controller.
> +
> +         UniPhier SoCs have SCSSI and MCSSI SPI controllers.
> +         Every UniPhier SoC has SCSSI which supports single channel.
> +         Older UniPhier Pro4/Pro5 also has MCSSI which support multiple channels.
> +         This driver supports SCSSI only.
> +
> +         If your SoC supports SCSSI, say Y here.
> +
>  config SPI_XCOMM
>         tristate "Analog Devices AD-FMCOMMS1-EBZ SPI-I2C-bridge driver"
>         depends on I2C
> diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
> index cb1f437..a90d559 100644
> --- a/drivers/spi/Makefile
> +++ b/drivers/spi/Makefile
> @@ -101,6 +101,7 @@ spi-thunderx-objs                   := spi-cavium.o spi-cavium-thunderx.o
>  obj-$(CONFIG_SPI_THUNDERX)             += spi-thunderx.o
>  obj-$(CONFIG_SPI_TOPCLIFF_PCH)         += spi-topcliff-pch.o
>  obj-$(CONFIG_SPI_TXX9)                 += spi-txx9.o
> +obj-$(CONFIG_SPI_UNIPHIER)             += spi-uniphier.o
>  obj-$(CONFIG_SPI_XCOMM)                += spi-xcomm.o
>  obj-$(CONFIG_SPI_XILINX)               += spi-xilinx.o
>  obj-$(CONFIG_SPI_XLP)                  += spi-xlp.o
> diff --git a/drivers/spi/spi-uniphier.c b/drivers/spi/spi-uniphier.c
> new file mode 100644
> index 0000000..0899854
> --- /dev/null
> +++ b/drivers/spi/spi-uniphier.c
> @@ -0,0 +1,525 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// spi-uniphier.c - Socionext UniPhier SPI controller driver
> +// Copyright 2012      Panasonic Corporation
> +// Copyright 2016-2018 Socionext Inc.
> +
> +#include <linux/kernel.h>
> +#include <linux/bitfield.h>
> +#include <linux/bitops.h>
> +#include <linux/clk.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/module.h>

> +#include <linux/of.h>
> +#include <linux/of_platform.h>

I fail to find where those two are used, just remove them.

> +#include <linux/platform_device.h>
> +#include <linux/spi/spi.h>
> +
> +#include <asm/unaligned.h>
> +
> +#define SSI_TIMEOUT_MS         2000
> +#define SSI_MAX_CLK_DIVIDER    254
> +#define SSI_MIN_CLK_DIVIDER    4
> +
> +struct uniphier_spi_priv {
> +       void __iomem *base;
> +       struct clk *clk;
> +       struct spi_master *master;
> +       struct completion xfer_done;
> +
> +       int error;
> +       unsigned int tx_bytes;
> +       unsigned int rx_bytes;
> +       const u8 *tx_buf;
> +       u8 *rx_buf;
> +
> +       bool is_save_param;
> +       u8 bits_per_word;
> +       u16 mode;
> +       u32 speed_hz;
> +};
> +
> +#define SSI_CTL                        0x00
> +#define   SSI_CTL_EN           BIT(0)
> +
> +#define SSI_CKS                        0x04
> +#define   SSI_CKS_CKRAT_MASK   GENMASK(7, 0)
> +#define   SSI_CKS_CKPHS                BIT(14)
> +#define   SSI_CKS_CKINIT       BIT(13)
> +#define   SSI_CKS_CKDLY                BIT(12)
> +
> +#define SSI_TXWDS              0x08
> +#define   SSI_TXWDS_WDLEN_MASK GENMASK(13, 8)
> +#define   SSI_TXWDS_TDTF_MASK  GENMASK(7, 6)
> +#define   SSI_TXWDS_DTLEN_MASK GENMASK(5, 0)
> +
> +#define SSI_RXWDS              0x0c
> +#define   SSI_RXWDS_DTLEN_MASK GENMASK(5, 0)
> +
> +#define SSI_FPS                        0x10
> +#define   SSI_FPS_FSPOL                BIT(15)
> +#define   SSI_FPS_FSTRT                BIT(14)
> +
> +#define SSI_SR                 0x14
> +#define   SSI_SR_RNE           BIT(0)
> +
> +#define SSI_IE                 0x18
> +#define   SSI_IE_RCIE          BIT(3)
> +#define   SSI_IE_RORIE         BIT(0)
> +
> +#define SSI_IS                 0x1c
> +#define   SSI_IS_RXRS          BIT(9)
> +#define   SSI_IS_RCID          BIT(3)
> +#define   SSI_IS_RORID         BIT(0)
> +
> +#define SSI_IC                 0x1c
> +#define   SSI_IC_TCIC          BIT(4)
> +#define   SSI_IC_RCIC          BIT(3)
> +#define   SSI_IC_RORIC         BIT(0)
> +
> +#define SSI_FC                 0x20
> +#define   SSI_FC_TXFFL         BIT(12)
> +#define   SSI_FC_TXFTH_MASK    GENMASK(11, 8)
> +#define   SSI_FC_RXFFL         BIT(4)
> +#define   SSI_FC_RXFTH_MASK    GENMASK(3, 0)
> +
> +#define SSI_TXDR               0x24
> +#define SSI_RXDR               0x24
> +
> +#define SSI_FIFO_DEPTH         8U
> +
> +static inline unsigned int bytes_per_word(unsigned int bits)
> +{
> +       return bits <= 8 ? 1 : (bits <= 16 ? 2 : 4);
> +}
> +
> +static inline void uniphier_spi_irq_enable(struct spi_device *spi, u32 mask)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> +       u32 val;
> +
> +       val = readl(priv->base + SSI_IE);
> +       val |= mask;
> +       writel(val, priv->base + SSI_IE);
> +}
> +
> +static inline void uniphier_spi_irq_disable(struct spi_device *spi, u32 mask)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> +       u32 val;
> +
> +       val = readl(priv->base + SSI_IE);
> +       val &= ~mask;
> +       writel(val, priv->base + SSI_IE);
> +}
> +
> +static void uniphier_spi_set_mode(struct spi_device *spi)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> +       u32 val1, val2;
> +
> +       /*
> +        * clock setting
> +        * CKPHS    capture timing. 0:rising edge, 1:falling edge
> +        * CKINIT   clock initial level. 0:low, 1:high
> +        * CKDLY    clock delay. 0:no delay, 1:delay depending on FSTRT
> +        *          (FSTRT=0: 1 clock, FSTRT=1: 0.5 clock)
> +        *
> +        * frame setting
> +        * FSPOL    frame signal porarity. 0: low, 1: high
> +        * FSTRT    start frame timing
> +        *          0: rising edge of clock, 1: falling edge of clock
> +        */
> +       switch (spi->mode & (SPI_CPOL | SPI_CPHA)) {
> +       case SPI_MODE_0:
> +               /* CKPHS=1, CKINIT=0, CKDLY=1, FSTRT=0 */
> +               val1 = SSI_CKS_CKPHS | SSI_CKS_CKDLY;
> +               val2 = 0;
> +               break;
> +       case SPI_MODE_1:
> +               /* CKPHS=0, CKINIT=0, CKDLY=0, FSTRT=1 */
> +               val1 = 0;
> +               val2 = SSI_FPS_FSTRT;
> +               break;
> +       case SPI_MODE_2:
> +               /* CKPHS=0, CKINIT=1, CKDLY=1, FSTRT=1 */
> +               val1 = SSI_CKS_CKINIT | SSI_CKS_CKDLY;
> +               val2 = SSI_FPS_FSTRT;
> +               break;
> +       case SPI_MODE_3:
> +               /* CKPHS=1, CKINIT=1, CKDLY=0, FSTRT=0 */
> +               val1 = SSI_CKS_CKPHS | SSI_CKS_CKINIT;
> +               val2 = 0;
> +               break;
> +       }
> +
> +       if (!(spi->mode & SPI_CS_HIGH))
> +               val2 |= SSI_FPS_FSPOL;
> +
> +       writel(val1, priv->base + SSI_CKS);
> +       writel(val2, priv->base + SSI_FPS);
> +
> +       val1 = 0;
> +       if (spi->mode & SPI_LSB_FIRST)
> +               val1 |= FIELD_PREP(SSI_TXWDS_TDTF_MASK, 1);
> +       writel(val1, priv->base + SSI_TXWDS);
> +       writel(val1, priv->base + SSI_RXWDS);
> +}
> +
> +static void uniphier_spi_set_transfer_size(struct spi_device *spi, int size)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> +       u32 val;
> +
> +       val = readl(priv->base + SSI_TXWDS);
> +       val &= ~(SSI_TXWDS_WDLEN_MASK | SSI_TXWDS_DTLEN_MASK);
> +       val |= FIELD_PREP(SSI_TXWDS_WDLEN_MASK, size);
> +       val |= FIELD_PREP(SSI_TXWDS_DTLEN_MASK, size);
> +       writel(val, priv->base + SSI_TXWDS);
> +
> +       val = readl(priv->base + SSI_RXWDS);
> +       val &= ~SSI_RXWDS_DTLEN_MASK;
> +       val |= FIELD_PREP(SSI_RXWDS_DTLEN_MASK, size);
> +       writel(val, priv->base + SSI_RXWDS);
> +}
> +
> +static void uniphier_spi_set_baudrate(struct spi_device *spi,
> +                                     unsigned int speed)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> +       u32 val, ckdiv;
> +
> +       /*
> +        * the supported rates are even numbers from 4 to 254. (4,6,8...254)
> +        * round up as we look for equal or less speed
> +        */
> +       ckdiv = DIV_ROUND_UP(clk_get_rate(priv->clk), speed);
> +       ckdiv = round_up(ckdiv, 2);
> +
> +       val = readl(priv->base + SSI_CKS);
> +       val &= ~SSI_CKS_CKRAT_MASK;
> +       val |= ckdiv & SSI_CKS_CKRAT_MASK;
> +       writel(val, priv->base + SSI_CKS);
> +}
> +
> +static void uniphier_spi_setup_transfer(struct spi_device *spi,
> +                                      struct spi_transfer *t)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> +       u32 val;
> +
> +       priv->error = 0;
> +       priv->tx_buf = t->tx_buf;
> +       priv->rx_buf = t->rx_buf;
> +       priv->tx_bytes = priv->rx_bytes = t->len;
> +
> +       if (!priv->is_save_param || priv->mode != spi->mode) {
> +               uniphier_spi_set_mode(spi);
> +               priv->mode = spi->mode;
> +       }
> +
> +       if (!priv->is_save_param || priv->bits_per_word != t->bits_per_word) {
> +               uniphier_spi_set_transfer_size(spi, t->bits_per_word);
> +               priv->bits_per_word = t->bits_per_word;
> +       }
> +
> +       if (!priv->is_save_param || priv->speed_hz != t->speed_hz) {
> +               uniphier_spi_set_baudrate(spi, t->speed_hz);
> +               priv->speed_hz = t->speed_hz;
> +       }
> +
> +       if (!priv->is_save_param)
> +               priv->is_save_param = true;
> +
> +       /* reset FIFOs */
> +       val = SSI_FC_TXFFL | SSI_FC_RXFFL;
> +       writel(val, priv->base + SSI_FC);
> +}
> +
> +static void uniphier_spi_send(struct uniphier_spi_priv *priv)
> +{
> +       int wsize;
> +       u32 val = 0;
> +
> +       wsize = min(bytes_per_word(priv->bits_per_word), priv->tx_bytes);
> +       priv->tx_bytes -= wsize;
> +
> +       if (priv->tx_buf) {
> +               switch (wsize) {
> +               case 1:
> +                       val = *priv->tx_buf;
> +                       break;
> +               case 2:
> +                       val = get_unaligned_le16(priv->tx_buf);
> +                       break;
> +               case 4:
> +                       val = get_unaligned_le32(priv->tx_buf);
> +                       break;
> +               }
> +
> +               priv->tx_buf += wsize;
> +       }
> +
> +       writel(val, priv->base + SSI_TXDR);
> +}
> +
> +static void uniphier_spi_recv(struct uniphier_spi_priv *priv)
> +{
> +       int rsize;
> +       u32 val;
> +
> +       rsize = min(bytes_per_word(priv->bits_per_word), priv->rx_bytes);
> +       priv->rx_bytes -= rsize;
> +
> +       val = readl(priv->base + SSI_RXDR);
> +
> +       if (priv->rx_buf) {
> +               switch (rsize) {
> +               case 1:
> +                       *priv->rx_buf = val;
> +                       break;
> +               case 2:
> +                       put_unaligned_le16(val, priv->rx_buf);
> +                       break;
> +               case 4:
> +                       put_unaligned_le32(val, priv->rx_buf);
> +                       break;
> +               }
> +
> +               priv->rx_buf += rsize;
> +       }
> +}
> +
> +static void uniphier_spi_fill_tx_fifo(struct uniphier_spi_priv *priv)
> +{
> +       unsigned int tx_count;
> +       u32 val;
> +
> +       tx_count = DIV_ROUND_UP(priv->tx_bytes,
> +                               bytes_per_word(priv->bits_per_word));
> +       tx_count = min(tx_count, SSI_FIFO_DEPTH);
> +
> +       /* set fifo threshold */
> +       val = readl(priv->base + SSI_FC);
> +       val &= ~(SSI_FC_TXFTH_MASK | SSI_FC_RXFTH_MASK);
> +       val |= FIELD_PREP(SSI_FC_TXFTH_MASK, tx_count);
> +       val |= FIELD_PREP(SSI_FC_RXFTH_MASK, tx_count);
> +       writel(val, priv->base + SSI_FC);
> +
> +       while (tx_count--)
> +               uniphier_spi_send(priv);
> +}
> +
> +static void uniphier_spi_set_cs(struct spi_device *spi, bool enable)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> +       u32 val;
> +
> +       val = readl(priv->base + SSI_FPS);
> +
> +       if (enable)
> +               val |= SSI_FPS_FSPOL;
> +       else
> +               val &= ~SSI_FPS_FSPOL;
> +
> +       writel(val, priv->base + SSI_FPS);
> +}
> +
> +static int uniphier_spi_transfer_one(struct spi_master *master,
> +                                    struct spi_device *spi,
> +                                    struct spi_transfer *t)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
> +       int status;
> +
> +       uniphier_spi_setup_transfer(spi, t);
> +
> +       reinit_completion(&priv->xfer_done);
> +
> +       uniphier_spi_fill_tx_fifo(priv);
> +
> +       uniphier_spi_irq_enable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
> +
> +       status = wait_for_completion_timeout(&priv->xfer_done,
> +                                            msecs_to_jiffies(SSI_TIMEOUT_MS));
> +
> +       uniphier_spi_irq_disable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
> +
> +       if (status < 0)
> +               return status;
> +
> +       return priv->error;
> +}
> +
> +static int uniphier_spi_prepare_transfer_hardware(struct spi_master *master)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
> +
> +       writel(SSI_CTL_EN, priv->base + SSI_CTL);
> +
> +       return 0;
> +}
> +
> +static int uniphier_spi_unprepare_transfer_hardware(struct spi_master *master)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
> +
> +       writel(0, priv->base + SSI_CTL);
> +
> +       return 0;
> +}
> +
> +static irqreturn_t uniphier_spi_handler(int irq, void *dev_id)
> +{
> +       struct uniphier_spi_priv *priv = dev_id;
> +       u32 val, stat;
> +
> +       stat = readl(priv->base + SSI_IS);
> +       val = SSI_IC_TCIC | SSI_IC_RCIC | SSI_IC_RORIC;
> +       writel(val, priv->base + SSI_IC);
> +
> +       /* rx fifo overrun */
> +       if (stat & SSI_IS_RORID) {
> +               priv->error = -EIO;
> +               goto done;
> +       }
> +
> +       /* rx complete */
> +       if ((stat & SSI_IS_RCID) && (stat & SSI_IS_RXRS)) {
> +               while ((readl(priv->base + SSI_SR) & SSI_SR_RNE) &&
> +                               (priv->rx_bytes - priv->tx_bytes) > 0)
> +                       uniphier_spi_recv(priv);
> +
> +               if ((readl(priv->base + SSI_SR) & SSI_SR_RNE) ||
> +                               (priv->rx_bytes != priv->tx_bytes)) {
> +                       priv->error = -EIO;
> +                       goto done;
> +               } else if (priv->rx_bytes == 0)
> +                       goto done;
> +
> +               /* next tx transfer */
> +               uniphier_spi_fill_tx_fifo(priv);
> +
> +               return IRQ_HANDLED;
> +       }
> +
> +       return IRQ_NONE;
> +
> +done:
> +       complete(&priv->xfer_done);
> +       return IRQ_HANDLED;
> +}
> +
> +static int uniphier_spi_probe(struct platform_device *pdev)
> +{
> +       struct uniphier_spi_priv *priv;
> +       struct spi_master *master;
> +       struct resource *res;
> +       unsigned long clk_rate;
> +       int irq;
> +       int ret;
> +
> +       master = spi_alloc_master(&pdev->dev, sizeof(*priv));
> +       if (!master)
> +               return -ENOMEM;
> +
> +       platform_set_drvdata(pdev, master);
> +
> +       priv = spi_master_get_devdata(master);
> +       priv->master = master;
> +       priv->is_save_param = false;
> +
> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +       priv->base = devm_ioremap_resource(&pdev->dev, res);
> +       if (IS_ERR(priv->base)) {
> +               ret = PTR_ERR(priv->base);
> +               goto out_master_put;
> +       }
> +
> +       priv->clk = devm_clk_get(&pdev->dev, NULL);
> +       if (IS_ERR(priv->clk)) {
> +               dev_err(&pdev->dev, "failed to get clock\n");
> +               ret = PTR_ERR(priv->clk);
> +               goto out_master_put;
> +       }
> +
> +       ret = clk_prepare_enable(priv->clk);
> +       if (ret)
> +               goto out_master_put;
> +
> +       irq = platform_get_irq(pdev, 0);
> +       if (irq < 0) {
> +               dev_err(&pdev->dev, "failed to get IRQ\n");
> +               ret = irq;
> +               goto out_disable_clk;
> +       }
> +
> +       ret = devm_request_irq(&pdev->dev, irq, uniphier_spi_handler,
> +                              0, "uniphier-spi", priv);
> +       if (ret) {
> +               dev_err(&pdev->dev, "failed to request IRQ\n");
> +               goto out_disable_clk;
> +       }
> +
> +       init_completion(&priv->xfer_done);
> +
> +       clk_rate = clk_get_rate(priv->clk);
> +
> +       master->max_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MIN_CLK_DIVIDER);
> +       master->min_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MAX_CLK_DIVIDER);
> +       master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
> +       master->dev.of_node = pdev->dev.of_node;
> +       master->bus_num = pdev->id;
> +       master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
> +
> +       master->set_cs = uniphier_spi_set_cs;
> +       master->transfer_one = uniphier_spi_transfer_one;
> +       master->prepare_transfer_hardware
> +                               = uniphier_spi_prepare_transfer_hardware;
> +       master->unprepare_transfer_hardware
> +                               = uniphier_spi_unprepare_transfer_hardware;
> +       master->num_chipselect = 1;
> +
> +       ret = devm_spi_register_master(&pdev->dev, master);
> +       if (ret)
> +               goto out_disable_clk;
> +
> +       return 0;
> +
> +out_disable_clk:
> +       clk_disable_unprepare(priv->clk);
> +
> +out_master_put:
> +       spi_master_put(master);
> +       return ret;
> +}
> +
> +static int uniphier_spi_remove(struct platform_device *pdev)
> +{
> +       struct uniphier_spi_priv *priv = platform_get_drvdata(pdev);
> +
> +       clk_disable_unprepare(priv->clk);
> +
> +       return 0;
> +}
> +
> +static const struct of_device_id uniphier_spi_match[] = {
> +       { .compatible = "socionext,uniphier-scssi" },
> +       { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, uniphier_spi_match);
> +
> +static struct platform_driver uniphier_spi_driver = {
> +       .probe = uniphier_spi_probe,
> +       .remove = uniphier_spi_remove,
> +       .driver = {
> +               .name = "uniphier-spi",
> +               .of_match_table = uniphier_spi_match,
> +       },
> +};
> +module_platform_driver(uniphier_spi_driver);
> +
> +MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
> +MODULE_AUTHOR("Keiji Hayashibara <hayashibara.keiji@socionext.com>");
> +MODULE_DESCRIPTION("Socionext UniPhier SPI controller driver");
> +MODULE_LICENSE("GPL v2");
> --
> 2.7.4
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-spi" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html



-- 
With Best Regards,
Andy Shevchenko

^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH v3 2/2] spi: add SPI controller driver for UniPhier SoC
@ 2018-08-01 10:20     ` Andy Shevchenko
  0 siblings, 0 replies; 14+ messages in thread
From: Andy Shevchenko @ 2018-08-01 10:20 UTC (permalink / raw)
  To: linux-arm-kernel

On Wed, Aug 1, 2018 at 10:29 AM, Keiji Hayashibara
<hayashibara.keiji@socionext.com> wrote:
> Add SPI controller driver implemented in Socionext UniPhier SoCs.
>
> UniPhier SoCs have two types SPI controllers; SCSSI supports a
> single channel, and MCSSI supports multiple channels.
> This driver supports SCSSI only.
>
> This controller has 32bit TX/RX FIFO with depth of eight entry,
> and supports the SPI master mode only.
>
> This commit is implemented in PIO transfer mode, not DMA transfer.
>

One comment below, otherwise FWIW,
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>


> Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
> Signed-off-by: Keiji Hayashibara <hayashibara.keiji@socionext.com>
> ---
>  drivers/spi/Kconfig        |  13 ++
>  drivers/spi/Makefile       |   1 +
>  drivers/spi/spi-uniphier.c | 525 +++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 539 insertions(+)
>  create mode 100644 drivers/spi/spi-uniphier.c
>
> diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
> index ad5d68e..671d078 100644
> --- a/drivers/spi/Kconfig
> +++ b/drivers/spi/Kconfig
> @@ -688,6 +688,19 @@ config SPI_TXX9
>         help
>           SPI driver for Toshiba TXx9 MIPS SoCs
>
> +config SPI_UNIPHIER
> +       tristate "Socionext UniPhier SPI Controller"
> +       depends on (ARCH_UNIPHIER || COMPILE_TEST) && OF
> +       help
> +         This enables a driver for the Socionext UniPhier SoC SCSSI SPI controller.
> +
> +         UniPhier SoCs have SCSSI and MCSSI SPI controllers.
> +         Every UniPhier SoC has SCSSI which supports single channel.
> +         Older UniPhier Pro4/Pro5 also has MCSSI which support multiple channels.
> +         This driver supports SCSSI only.
> +
> +         If your SoC supports SCSSI, say Y here.
> +
>  config SPI_XCOMM
>         tristate "Analog Devices AD-FMCOMMS1-EBZ SPI-I2C-bridge driver"
>         depends on I2C
> diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
> index cb1f437..a90d559 100644
> --- a/drivers/spi/Makefile
> +++ b/drivers/spi/Makefile
> @@ -101,6 +101,7 @@ spi-thunderx-objs                   := spi-cavium.o spi-cavium-thunderx.o
>  obj-$(CONFIG_SPI_THUNDERX)             += spi-thunderx.o
>  obj-$(CONFIG_SPI_TOPCLIFF_PCH)         += spi-topcliff-pch.o
>  obj-$(CONFIG_SPI_TXX9)                 += spi-txx9.o
> +obj-$(CONFIG_SPI_UNIPHIER)             += spi-uniphier.o
>  obj-$(CONFIG_SPI_XCOMM)                += spi-xcomm.o
>  obj-$(CONFIG_SPI_XILINX)               += spi-xilinx.o
>  obj-$(CONFIG_SPI_XLP)                  += spi-xlp.o
> diff --git a/drivers/spi/spi-uniphier.c b/drivers/spi/spi-uniphier.c
> new file mode 100644
> index 0000000..0899854
> --- /dev/null
> +++ b/drivers/spi/spi-uniphier.c
> @@ -0,0 +1,525 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// spi-uniphier.c - Socionext UniPhier SPI controller driver
> +// Copyright 2012      Panasonic Corporation
> +// Copyright 2016-2018 Socionext Inc.
> +
> +#include <linux/kernel.h>
> +#include <linux/bitfield.h>
> +#include <linux/bitops.h>
> +#include <linux/clk.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/module.h>

> +#include <linux/of.h>
> +#include <linux/of_platform.h>

I fail to find where those two are used, just remove them.

> +#include <linux/platform_device.h>
> +#include <linux/spi/spi.h>
> +
> +#include <asm/unaligned.h>
> +
> +#define SSI_TIMEOUT_MS         2000
> +#define SSI_MAX_CLK_DIVIDER    254
> +#define SSI_MIN_CLK_DIVIDER    4
> +
> +struct uniphier_spi_priv {
> +       void __iomem *base;
> +       struct clk *clk;
> +       struct spi_master *master;
> +       struct completion xfer_done;
> +
> +       int error;
> +       unsigned int tx_bytes;
> +       unsigned int rx_bytes;
> +       const u8 *tx_buf;
> +       u8 *rx_buf;
> +
> +       bool is_save_param;
> +       u8 bits_per_word;
> +       u16 mode;
> +       u32 speed_hz;
> +};
> +
> +#define SSI_CTL                        0x00
> +#define   SSI_CTL_EN           BIT(0)
> +
> +#define SSI_CKS                        0x04
> +#define   SSI_CKS_CKRAT_MASK   GENMASK(7, 0)
> +#define   SSI_CKS_CKPHS                BIT(14)
> +#define   SSI_CKS_CKINIT       BIT(13)
> +#define   SSI_CKS_CKDLY                BIT(12)
> +
> +#define SSI_TXWDS              0x08
> +#define   SSI_TXWDS_WDLEN_MASK GENMASK(13, 8)
> +#define   SSI_TXWDS_TDTF_MASK  GENMASK(7, 6)
> +#define   SSI_TXWDS_DTLEN_MASK GENMASK(5, 0)
> +
> +#define SSI_RXWDS              0x0c
> +#define   SSI_RXWDS_DTLEN_MASK GENMASK(5, 0)
> +
> +#define SSI_FPS                        0x10
> +#define   SSI_FPS_FSPOL                BIT(15)
> +#define   SSI_FPS_FSTRT                BIT(14)
> +
> +#define SSI_SR                 0x14
> +#define   SSI_SR_RNE           BIT(0)
> +
> +#define SSI_IE                 0x18
> +#define   SSI_IE_RCIE          BIT(3)
> +#define   SSI_IE_RORIE         BIT(0)
> +
> +#define SSI_IS                 0x1c
> +#define   SSI_IS_RXRS          BIT(9)
> +#define   SSI_IS_RCID          BIT(3)
> +#define   SSI_IS_RORID         BIT(0)
> +
> +#define SSI_IC                 0x1c
> +#define   SSI_IC_TCIC          BIT(4)
> +#define   SSI_IC_RCIC          BIT(3)
> +#define   SSI_IC_RORIC         BIT(0)
> +
> +#define SSI_FC                 0x20
> +#define   SSI_FC_TXFFL         BIT(12)
> +#define   SSI_FC_TXFTH_MASK    GENMASK(11, 8)
> +#define   SSI_FC_RXFFL         BIT(4)
> +#define   SSI_FC_RXFTH_MASK    GENMASK(3, 0)
> +
> +#define SSI_TXDR               0x24
> +#define SSI_RXDR               0x24
> +
> +#define SSI_FIFO_DEPTH         8U
> +
> +static inline unsigned int bytes_per_word(unsigned int bits)
> +{
> +       return bits <= 8 ? 1 : (bits <= 16 ? 2 : 4);
> +}
> +
> +static inline void uniphier_spi_irq_enable(struct spi_device *spi, u32 mask)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> +       u32 val;
> +
> +       val = readl(priv->base + SSI_IE);
> +       val |= mask;
> +       writel(val, priv->base + SSI_IE);
> +}
> +
> +static inline void uniphier_spi_irq_disable(struct spi_device *spi, u32 mask)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> +       u32 val;
> +
> +       val = readl(priv->base + SSI_IE);
> +       val &= ~mask;
> +       writel(val, priv->base + SSI_IE);
> +}
> +
> +static void uniphier_spi_set_mode(struct spi_device *spi)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> +       u32 val1, val2;
> +
> +       /*
> +        * clock setting
> +        * CKPHS    capture timing. 0:rising edge, 1:falling edge
> +        * CKINIT   clock initial level. 0:low, 1:high
> +        * CKDLY    clock delay. 0:no delay, 1:delay depending on FSTRT
> +        *          (FSTRT=0: 1 clock, FSTRT=1: 0.5 clock)
> +        *
> +        * frame setting
> +        * FSPOL    frame signal porarity. 0: low, 1: high
> +        * FSTRT    start frame timing
> +        *          0: rising edge of clock, 1: falling edge of clock
> +        */
> +       switch (spi->mode & (SPI_CPOL | SPI_CPHA)) {
> +       case SPI_MODE_0:
> +               /* CKPHS=1, CKINIT=0, CKDLY=1, FSTRT=0 */
> +               val1 = SSI_CKS_CKPHS | SSI_CKS_CKDLY;
> +               val2 = 0;
> +               break;
> +       case SPI_MODE_1:
> +               /* CKPHS=0, CKINIT=0, CKDLY=0, FSTRT=1 */
> +               val1 = 0;
> +               val2 = SSI_FPS_FSTRT;
> +               break;
> +       case SPI_MODE_2:
> +               /* CKPHS=0, CKINIT=1, CKDLY=1, FSTRT=1 */
> +               val1 = SSI_CKS_CKINIT | SSI_CKS_CKDLY;
> +               val2 = SSI_FPS_FSTRT;
> +               break;
> +       case SPI_MODE_3:
> +               /* CKPHS=1, CKINIT=1, CKDLY=0, FSTRT=0 */
> +               val1 = SSI_CKS_CKPHS | SSI_CKS_CKINIT;
> +               val2 = 0;
> +               break;
> +       }
> +
> +       if (!(spi->mode & SPI_CS_HIGH))
> +               val2 |= SSI_FPS_FSPOL;
> +
> +       writel(val1, priv->base + SSI_CKS);
> +       writel(val2, priv->base + SSI_FPS);
> +
> +       val1 = 0;
> +       if (spi->mode & SPI_LSB_FIRST)
> +               val1 |= FIELD_PREP(SSI_TXWDS_TDTF_MASK, 1);
> +       writel(val1, priv->base + SSI_TXWDS);
> +       writel(val1, priv->base + SSI_RXWDS);
> +}
> +
> +static void uniphier_spi_set_transfer_size(struct spi_device *spi, int size)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> +       u32 val;
> +
> +       val = readl(priv->base + SSI_TXWDS);
> +       val &= ~(SSI_TXWDS_WDLEN_MASK | SSI_TXWDS_DTLEN_MASK);
> +       val |= FIELD_PREP(SSI_TXWDS_WDLEN_MASK, size);
> +       val |= FIELD_PREP(SSI_TXWDS_DTLEN_MASK, size);
> +       writel(val, priv->base + SSI_TXWDS);
> +
> +       val = readl(priv->base + SSI_RXWDS);
> +       val &= ~SSI_RXWDS_DTLEN_MASK;
> +       val |= FIELD_PREP(SSI_RXWDS_DTLEN_MASK, size);
> +       writel(val, priv->base + SSI_RXWDS);
> +}
> +
> +static void uniphier_spi_set_baudrate(struct spi_device *spi,
> +                                     unsigned int speed)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> +       u32 val, ckdiv;
> +
> +       /*
> +        * the supported rates are even numbers from 4 to 254. (4,6,8...254)
> +        * round up as we look for equal or less speed
> +        */
> +       ckdiv = DIV_ROUND_UP(clk_get_rate(priv->clk), speed);
> +       ckdiv = round_up(ckdiv, 2);
> +
> +       val = readl(priv->base + SSI_CKS);
> +       val &= ~SSI_CKS_CKRAT_MASK;
> +       val |= ckdiv & SSI_CKS_CKRAT_MASK;
> +       writel(val, priv->base + SSI_CKS);
> +}
> +
> +static void uniphier_spi_setup_transfer(struct spi_device *spi,
> +                                      struct spi_transfer *t)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> +       u32 val;
> +
> +       priv->error = 0;
> +       priv->tx_buf = t->tx_buf;
> +       priv->rx_buf = t->rx_buf;
> +       priv->tx_bytes = priv->rx_bytes = t->len;
> +
> +       if (!priv->is_save_param || priv->mode != spi->mode) {
> +               uniphier_spi_set_mode(spi);
> +               priv->mode = spi->mode;
> +       }
> +
> +       if (!priv->is_save_param || priv->bits_per_word != t->bits_per_word) {
> +               uniphier_spi_set_transfer_size(spi, t->bits_per_word);
> +               priv->bits_per_word = t->bits_per_word;
> +       }
> +
> +       if (!priv->is_save_param || priv->speed_hz != t->speed_hz) {
> +               uniphier_spi_set_baudrate(spi, t->speed_hz);
> +               priv->speed_hz = t->speed_hz;
> +       }
> +
> +       if (!priv->is_save_param)
> +               priv->is_save_param = true;
> +
> +       /* reset FIFOs */
> +       val = SSI_FC_TXFFL | SSI_FC_RXFFL;
> +       writel(val, priv->base + SSI_FC);
> +}
> +
> +static void uniphier_spi_send(struct uniphier_spi_priv *priv)
> +{
> +       int wsize;
> +       u32 val = 0;
> +
> +       wsize = min(bytes_per_word(priv->bits_per_word), priv->tx_bytes);
> +       priv->tx_bytes -= wsize;
> +
> +       if (priv->tx_buf) {
> +               switch (wsize) {
> +               case 1:
> +                       val = *priv->tx_buf;
> +                       break;
> +               case 2:
> +                       val = get_unaligned_le16(priv->tx_buf);
> +                       break;
> +               case 4:
> +                       val = get_unaligned_le32(priv->tx_buf);
> +                       break;
> +               }
> +
> +               priv->tx_buf += wsize;
> +       }
> +
> +       writel(val, priv->base + SSI_TXDR);
> +}
> +
> +static void uniphier_spi_recv(struct uniphier_spi_priv *priv)
> +{
> +       int rsize;
> +       u32 val;
> +
> +       rsize = min(bytes_per_word(priv->bits_per_word), priv->rx_bytes);
> +       priv->rx_bytes -= rsize;
> +
> +       val = readl(priv->base + SSI_RXDR);
> +
> +       if (priv->rx_buf) {
> +               switch (rsize) {
> +               case 1:
> +                       *priv->rx_buf = val;
> +                       break;
> +               case 2:
> +                       put_unaligned_le16(val, priv->rx_buf);
> +                       break;
> +               case 4:
> +                       put_unaligned_le32(val, priv->rx_buf);
> +                       break;
> +               }
> +
> +               priv->rx_buf += rsize;
> +       }
> +}
> +
> +static void uniphier_spi_fill_tx_fifo(struct uniphier_spi_priv *priv)
> +{
> +       unsigned int tx_count;
> +       u32 val;
> +
> +       tx_count = DIV_ROUND_UP(priv->tx_bytes,
> +                               bytes_per_word(priv->bits_per_word));
> +       tx_count = min(tx_count, SSI_FIFO_DEPTH);
> +
> +       /* set fifo threshold */
> +       val = readl(priv->base + SSI_FC);
> +       val &= ~(SSI_FC_TXFTH_MASK | SSI_FC_RXFTH_MASK);
> +       val |= FIELD_PREP(SSI_FC_TXFTH_MASK, tx_count);
> +       val |= FIELD_PREP(SSI_FC_RXFTH_MASK, tx_count);
> +       writel(val, priv->base + SSI_FC);
> +
> +       while (tx_count--)
> +               uniphier_spi_send(priv);
> +}
> +
> +static void uniphier_spi_set_cs(struct spi_device *spi, bool enable)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> +       u32 val;
> +
> +       val = readl(priv->base + SSI_FPS);
> +
> +       if (enable)
> +               val |= SSI_FPS_FSPOL;
> +       else
> +               val &= ~SSI_FPS_FSPOL;
> +
> +       writel(val, priv->base + SSI_FPS);
> +}
> +
> +static int uniphier_spi_transfer_one(struct spi_master *master,
> +                                    struct spi_device *spi,
> +                                    struct spi_transfer *t)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
> +       int status;
> +
> +       uniphier_spi_setup_transfer(spi, t);
> +
> +       reinit_completion(&priv->xfer_done);
> +
> +       uniphier_spi_fill_tx_fifo(priv);
> +
> +       uniphier_spi_irq_enable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
> +
> +       status = wait_for_completion_timeout(&priv->xfer_done,
> +                                            msecs_to_jiffies(SSI_TIMEOUT_MS));
> +
> +       uniphier_spi_irq_disable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
> +
> +       if (status < 0)
> +               return status;
> +
> +       return priv->error;
> +}
> +
> +static int uniphier_spi_prepare_transfer_hardware(struct spi_master *master)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
> +
> +       writel(SSI_CTL_EN, priv->base + SSI_CTL);
> +
> +       return 0;
> +}
> +
> +static int uniphier_spi_unprepare_transfer_hardware(struct spi_master *master)
> +{
> +       struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
> +
> +       writel(0, priv->base + SSI_CTL);
> +
> +       return 0;
> +}
> +
> +static irqreturn_t uniphier_spi_handler(int irq, void *dev_id)
> +{
> +       struct uniphier_spi_priv *priv = dev_id;
> +       u32 val, stat;
> +
> +       stat = readl(priv->base + SSI_IS);
> +       val = SSI_IC_TCIC | SSI_IC_RCIC | SSI_IC_RORIC;
> +       writel(val, priv->base + SSI_IC);
> +
> +       /* rx fifo overrun */
> +       if (stat & SSI_IS_RORID) {
> +               priv->error = -EIO;
> +               goto done;
> +       }
> +
> +       /* rx complete */
> +       if ((stat & SSI_IS_RCID) && (stat & SSI_IS_RXRS)) {
> +               while ((readl(priv->base + SSI_SR) & SSI_SR_RNE) &&
> +                               (priv->rx_bytes - priv->tx_bytes) > 0)
> +                       uniphier_spi_recv(priv);
> +
> +               if ((readl(priv->base + SSI_SR) & SSI_SR_RNE) ||
> +                               (priv->rx_bytes != priv->tx_bytes)) {
> +                       priv->error = -EIO;
> +                       goto done;
> +               } else if (priv->rx_bytes == 0)
> +                       goto done;
> +
> +               /* next tx transfer */
> +               uniphier_spi_fill_tx_fifo(priv);
> +
> +               return IRQ_HANDLED;
> +       }
> +
> +       return IRQ_NONE;
> +
> +done:
> +       complete(&priv->xfer_done);
> +       return IRQ_HANDLED;
> +}
> +
> +static int uniphier_spi_probe(struct platform_device *pdev)
> +{
> +       struct uniphier_spi_priv *priv;
> +       struct spi_master *master;
> +       struct resource *res;
> +       unsigned long clk_rate;
> +       int irq;
> +       int ret;
> +
> +       master = spi_alloc_master(&pdev->dev, sizeof(*priv));
> +       if (!master)
> +               return -ENOMEM;
> +
> +       platform_set_drvdata(pdev, master);
> +
> +       priv = spi_master_get_devdata(master);
> +       priv->master = master;
> +       priv->is_save_param = false;
> +
> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +       priv->base = devm_ioremap_resource(&pdev->dev, res);
> +       if (IS_ERR(priv->base)) {
> +               ret = PTR_ERR(priv->base);
> +               goto out_master_put;
> +       }
> +
> +       priv->clk = devm_clk_get(&pdev->dev, NULL);
> +       if (IS_ERR(priv->clk)) {
> +               dev_err(&pdev->dev, "failed to get clock\n");
> +               ret = PTR_ERR(priv->clk);
> +               goto out_master_put;
> +       }
> +
> +       ret = clk_prepare_enable(priv->clk);
> +       if (ret)
> +               goto out_master_put;
> +
> +       irq = platform_get_irq(pdev, 0);
> +       if (irq < 0) {
> +               dev_err(&pdev->dev, "failed to get IRQ\n");
> +               ret = irq;
> +               goto out_disable_clk;
> +       }
> +
> +       ret = devm_request_irq(&pdev->dev, irq, uniphier_spi_handler,
> +                              0, "uniphier-spi", priv);
> +       if (ret) {
> +               dev_err(&pdev->dev, "failed to request IRQ\n");
> +               goto out_disable_clk;
> +       }
> +
> +       init_completion(&priv->xfer_done);
> +
> +       clk_rate = clk_get_rate(priv->clk);
> +
> +       master->max_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MIN_CLK_DIVIDER);
> +       master->min_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MAX_CLK_DIVIDER);
> +       master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
> +       master->dev.of_node = pdev->dev.of_node;
> +       master->bus_num = pdev->id;
> +       master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
> +
> +       master->set_cs = uniphier_spi_set_cs;
> +       master->transfer_one = uniphier_spi_transfer_one;
> +       master->prepare_transfer_hardware
> +                               = uniphier_spi_prepare_transfer_hardware;
> +       master->unprepare_transfer_hardware
> +                               = uniphier_spi_unprepare_transfer_hardware;
> +       master->num_chipselect = 1;
> +
> +       ret = devm_spi_register_master(&pdev->dev, master);
> +       if (ret)
> +               goto out_disable_clk;
> +
> +       return 0;
> +
> +out_disable_clk:
> +       clk_disable_unprepare(priv->clk);
> +
> +out_master_put:
> +       spi_master_put(master);
> +       return ret;
> +}
> +
> +static int uniphier_spi_remove(struct platform_device *pdev)
> +{
> +       struct uniphier_spi_priv *priv = platform_get_drvdata(pdev);
> +
> +       clk_disable_unprepare(priv->clk);
> +
> +       return 0;
> +}
> +
> +static const struct of_device_id uniphier_spi_match[] = {
> +       { .compatible = "socionext,uniphier-scssi" },
> +       { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, uniphier_spi_match);
> +
> +static struct platform_driver uniphier_spi_driver = {
> +       .probe = uniphier_spi_probe,
> +       .remove = uniphier_spi_remove,
> +       .driver = {
> +               .name = "uniphier-spi",
> +               .of_match_table = uniphier_spi_match,
> +       },
> +};
> +module_platform_driver(uniphier_spi_driver);
> +
> +MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
> +MODULE_AUTHOR("Keiji Hayashibara <hayashibara.keiji@socionext.com>");
> +MODULE_DESCRIPTION("Socionext UniPhier SPI controller driver");
> +MODULE_LICENSE("GPL v2");
> --
> 2.7.4
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-spi" in
> the body of a message to majordomo at vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html



-- 
With Best Regards,
Andy Shevchenko

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Applied "spi: add SPI controller driver for UniPhier SoC" to the spi tree
  2018-08-01  7:29   ` Keiji Hayashibara
  (?)
  (?)
@ 2018-08-01 11:20     ` Mark Brown
  -1 siblings, 0 replies; 14+ messages in thread
From: Mark Brown @ 2018-08-01 11:20 UTC (permalink / raw)
  To: Keiji Hayashibara
  Cc: Kunihiko Hayashi, Mark Brown, broonie, robh+dt, mark.rutland,
	yamada.masahiro, linux-spi, linux-arm-kernel, devicetree,
	masami.hiramatsu, jaswinder.singh, linux-kernel,
	hayashibara.keiji, Kunihiko Hayashi, linux-spi

The patch

   spi: add SPI controller driver for UniPhier SoC

has been applied to the spi tree at

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git 

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

From 5ba155a4d4cc8e4cdd3db6df7d03271a3bd91177 Mon Sep 17 00:00:00 2001
From: Keiji Hayashibara <hayashibara.keiji@socionext.com>
Date: Wed, 1 Aug 2018 16:29:12 +0900
Subject: [PATCH] spi: add SPI controller driver for UniPhier SoC

Add SPI controller driver implemented in Socionext UniPhier SoCs.

UniPhier SoCs have two types SPI controllers; SCSSI supports a
single channel, and MCSSI supports multiple channels.
This driver supports SCSSI only.

This controller has 32bit TX/RX FIFO with depth of eight entry,
and supports the SPI master mode only.

This commit is implemented in PIO transfer mode, not DMA transfer.

Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Keiji Hayashibara <hayashibara.keiji@socionext.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 drivers/spi/Kconfig        |  13 +
 drivers/spi/Makefile       |   1 +
 drivers/spi/spi-uniphier.c | 525 +++++++++++++++++++++++++++++++++++++
 3 files changed, 539 insertions(+)
 create mode 100644 drivers/spi/spi-uniphier.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index ad5d68e1dab7..671d078349cc 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -688,6 +688,19 @@ config SPI_TXX9
 	help
 	  SPI driver for Toshiba TXx9 MIPS SoCs
 
+config SPI_UNIPHIER
+	tristate "Socionext UniPhier SPI Controller"
+	depends on (ARCH_UNIPHIER || COMPILE_TEST) && OF
+	help
+	  This enables a driver for the Socionext UniPhier SoC SCSSI SPI controller.
+
+	  UniPhier SoCs have SCSSI and MCSSI SPI controllers.
+	  Every UniPhier SoC has SCSSI which supports single channel.
+	  Older UniPhier Pro4/Pro5 also has MCSSI which support multiple channels.
+	  This driver supports SCSSI only.
+
+	  If your SoC supports SCSSI, say Y here.
+
 config SPI_XCOMM
 	tristate "Analog Devices AD-FMCOMMS1-EBZ SPI-I2C-bridge driver"
 	depends on I2C
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index cb1f4378b87c..a90d55970036 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -101,6 +101,7 @@ spi-thunderx-objs			:= spi-cavium.o spi-cavium-thunderx.o
 obj-$(CONFIG_SPI_THUNDERX)		+= spi-thunderx.o
 obj-$(CONFIG_SPI_TOPCLIFF_PCH)		+= spi-topcliff-pch.o
 obj-$(CONFIG_SPI_TXX9)			+= spi-txx9.o
+obj-$(CONFIG_SPI_UNIPHIER)		+= spi-uniphier.o
 obj-$(CONFIG_SPI_XCOMM)		+= spi-xcomm.o
 obj-$(CONFIG_SPI_XILINX)		+= spi-xilinx.o
 obj-$(CONFIG_SPI_XLP)			+= spi-xlp.o
diff --git a/drivers/spi/spi-uniphier.c b/drivers/spi/spi-uniphier.c
new file mode 100644
index 000000000000..089985465890
--- /dev/null
+++ b/drivers/spi/spi-uniphier.c
@@ -0,0 +1,525 @@
+// SPDX-License-Identifier: GPL-2.0
+// spi-uniphier.c - Socionext UniPhier SPI controller driver
+// Copyright 2012      Panasonic Corporation
+// Copyright 2016-2018 Socionext Inc.
+
+#include <linux/kernel.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+
+#include <asm/unaligned.h>
+
+#define SSI_TIMEOUT_MS		2000
+#define SSI_MAX_CLK_DIVIDER	254
+#define SSI_MIN_CLK_DIVIDER	4
+
+struct uniphier_spi_priv {
+	void __iomem *base;
+	struct clk *clk;
+	struct spi_master *master;
+	struct completion xfer_done;
+
+	int error;
+	unsigned int tx_bytes;
+	unsigned int rx_bytes;
+	const u8 *tx_buf;
+	u8 *rx_buf;
+
+	bool is_save_param;
+	u8 bits_per_word;
+	u16 mode;
+	u32 speed_hz;
+};
+
+#define SSI_CTL			0x00
+#define   SSI_CTL_EN		BIT(0)
+
+#define SSI_CKS			0x04
+#define   SSI_CKS_CKRAT_MASK	GENMASK(7, 0)
+#define   SSI_CKS_CKPHS		BIT(14)
+#define   SSI_CKS_CKINIT	BIT(13)
+#define   SSI_CKS_CKDLY		BIT(12)
+
+#define SSI_TXWDS		0x08
+#define   SSI_TXWDS_WDLEN_MASK	GENMASK(13, 8)
+#define   SSI_TXWDS_TDTF_MASK	GENMASK(7, 6)
+#define   SSI_TXWDS_DTLEN_MASK	GENMASK(5, 0)
+
+#define SSI_RXWDS		0x0c
+#define   SSI_RXWDS_DTLEN_MASK	GENMASK(5, 0)
+
+#define SSI_FPS			0x10
+#define   SSI_FPS_FSPOL		BIT(15)
+#define   SSI_FPS_FSTRT		BIT(14)
+
+#define SSI_SR			0x14
+#define   SSI_SR_RNE		BIT(0)
+
+#define SSI_IE			0x18
+#define   SSI_IE_RCIE		BIT(3)
+#define   SSI_IE_RORIE		BIT(0)
+
+#define SSI_IS			0x1c
+#define   SSI_IS_RXRS		BIT(9)
+#define   SSI_IS_RCID		BIT(3)
+#define   SSI_IS_RORID		BIT(0)
+
+#define SSI_IC			0x1c
+#define   SSI_IC_TCIC		BIT(4)
+#define   SSI_IC_RCIC		BIT(3)
+#define   SSI_IC_RORIC		BIT(0)
+
+#define SSI_FC			0x20
+#define   SSI_FC_TXFFL		BIT(12)
+#define   SSI_FC_TXFTH_MASK	GENMASK(11, 8)
+#define   SSI_FC_RXFFL		BIT(4)
+#define   SSI_FC_RXFTH_MASK	GENMASK(3, 0)
+
+#define SSI_TXDR		0x24
+#define SSI_RXDR		0x24
+
+#define SSI_FIFO_DEPTH		8U
+
+static inline unsigned int bytes_per_word(unsigned int bits)
+{
+	return bits <= 8 ? 1 : (bits <= 16 ? 2 : 4);
+}
+
+static inline void uniphier_spi_irq_enable(struct spi_device *spi, u32 mask)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_IE);
+	val |= mask;
+	writel(val, priv->base + SSI_IE);
+}
+
+static inline void uniphier_spi_irq_disable(struct spi_device *spi, u32 mask)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_IE);
+	val &= ~mask;
+	writel(val, priv->base + SSI_IE);
+}
+
+static void uniphier_spi_set_mode(struct spi_device *spi)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val1, val2;
+
+	/*
+	 * clock setting
+	 * CKPHS    capture timing. 0:rising edge, 1:falling edge
+	 * CKINIT   clock initial level. 0:low, 1:high
+	 * CKDLY    clock delay. 0:no delay, 1:delay depending on FSTRT
+	 *          (FSTRT=0: 1 clock, FSTRT=1: 0.5 clock)
+	 *
+	 * frame setting
+	 * FSPOL    frame signal porarity. 0: low, 1: high
+	 * FSTRT    start frame timing
+	 *          0: rising edge of clock, 1: falling edge of clock
+	 */
+	switch (spi->mode & (SPI_CPOL | SPI_CPHA)) {
+	case SPI_MODE_0:
+		/* CKPHS=1, CKINIT=0, CKDLY=1, FSTRT=0 */
+		val1 = SSI_CKS_CKPHS | SSI_CKS_CKDLY;
+		val2 = 0;
+		break;
+	case SPI_MODE_1:
+		/* CKPHS=0, CKINIT=0, CKDLY=0, FSTRT=1 */
+		val1 = 0;
+		val2 = SSI_FPS_FSTRT;
+		break;
+	case SPI_MODE_2:
+		/* CKPHS=0, CKINIT=1, CKDLY=1, FSTRT=1 */
+		val1 = SSI_CKS_CKINIT | SSI_CKS_CKDLY;
+		val2 = SSI_FPS_FSTRT;
+		break;
+	case SPI_MODE_3:
+		/* CKPHS=1, CKINIT=1, CKDLY=0, FSTRT=0 */
+		val1 = SSI_CKS_CKPHS | SSI_CKS_CKINIT;
+		val2 = 0;
+		break;
+	}
+
+	if (!(spi->mode & SPI_CS_HIGH))
+		val2 |= SSI_FPS_FSPOL;
+
+	writel(val1, priv->base + SSI_CKS);
+	writel(val2, priv->base + SSI_FPS);
+
+	val1 = 0;
+	if (spi->mode & SPI_LSB_FIRST)
+		val1 |= FIELD_PREP(SSI_TXWDS_TDTF_MASK, 1);
+	writel(val1, priv->base + SSI_TXWDS);
+	writel(val1, priv->base + SSI_RXWDS);
+}
+
+static void uniphier_spi_set_transfer_size(struct spi_device *spi, int size)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_TXWDS);
+	val &= ~(SSI_TXWDS_WDLEN_MASK | SSI_TXWDS_DTLEN_MASK);
+	val |= FIELD_PREP(SSI_TXWDS_WDLEN_MASK, size);
+	val |= FIELD_PREP(SSI_TXWDS_DTLEN_MASK, size);
+	writel(val, priv->base + SSI_TXWDS);
+
+	val = readl(priv->base + SSI_RXWDS);
+	val &= ~SSI_RXWDS_DTLEN_MASK;
+	val |= FIELD_PREP(SSI_RXWDS_DTLEN_MASK, size);
+	writel(val, priv->base + SSI_RXWDS);
+}
+
+static void uniphier_spi_set_baudrate(struct spi_device *spi,
+				      unsigned int speed)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val, ckdiv;
+
+	/*
+	 * the supported rates are even numbers from 4 to 254. (4,6,8...254)
+	 * round up as we look for equal or less speed
+	 */
+	ckdiv = DIV_ROUND_UP(clk_get_rate(priv->clk), speed);
+	ckdiv = round_up(ckdiv, 2);
+
+	val = readl(priv->base + SSI_CKS);
+	val &= ~SSI_CKS_CKRAT_MASK;
+	val |= ckdiv & SSI_CKS_CKRAT_MASK;
+	writel(val, priv->base + SSI_CKS);
+}
+
+static void uniphier_spi_setup_transfer(struct spi_device *spi,
+				       struct spi_transfer *t)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	priv->error = 0;
+	priv->tx_buf = t->tx_buf;
+	priv->rx_buf = t->rx_buf;
+	priv->tx_bytes = priv->rx_bytes = t->len;
+
+	if (!priv->is_save_param || priv->mode != spi->mode) {
+		uniphier_spi_set_mode(spi);
+		priv->mode = spi->mode;
+	}
+
+	if (!priv->is_save_param || priv->bits_per_word != t->bits_per_word) {
+		uniphier_spi_set_transfer_size(spi, t->bits_per_word);
+		priv->bits_per_word = t->bits_per_word;
+	}
+
+	if (!priv->is_save_param || priv->speed_hz != t->speed_hz) {
+		uniphier_spi_set_baudrate(spi, t->speed_hz);
+		priv->speed_hz = t->speed_hz;
+	}
+
+	if (!priv->is_save_param)
+		priv->is_save_param = true;
+
+	/* reset FIFOs */
+	val = SSI_FC_TXFFL | SSI_FC_RXFFL;
+	writel(val, priv->base + SSI_FC);
+}
+
+static void uniphier_spi_send(struct uniphier_spi_priv *priv)
+{
+	int wsize;
+	u32 val = 0;
+
+	wsize = min(bytes_per_word(priv->bits_per_word), priv->tx_bytes);
+	priv->tx_bytes -= wsize;
+
+	if (priv->tx_buf) {
+		switch (wsize) {
+		case 1:
+			val = *priv->tx_buf;
+			break;
+		case 2:
+			val = get_unaligned_le16(priv->tx_buf);
+			break;
+		case 4:
+			val = get_unaligned_le32(priv->tx_buf);
+			break;
+		}
+
+		priv->tx_buf += wsize;
+	}
+
+	writel(val, priv->base + SSI_TXDR);
+}
+
+static void uniphier_spi_recv(struct uniphier_spi_priv *priv)
+{
+	int rsize;
+	u32 val;
+
+	rsize = min(bytes_per_word(priv->bits_per_word), priv->rx_bytes);
+	priv->rx_bytes -= rsize;
+
+	val = readl(priv->base + SSI_RXDR);
+
+	if (priv->rx_buf) {
+		switch (rsize) {
+		case 1:
+			*priv->rx_buf = val;
+			break;
+		case 2:
+			put_unaligned_le16(val, priv->rx_buf);
+			break;
+		case 4:
+			put_unaligned_le32(val, priv->rx_buf);
+			break;
+		}
+
+		priv->rx_buf += rsize;
+	}
+}
+
+static void uniphier_spi_fill_tx_fifo(struct uniphier_spi_priv *priv)
+{
+	unsigned int tx_count;
+	u32 val;
+
+	tx_count = DIV_ROUND_UP(priv->tx_bytes,
+				bytes_per_word(priv->bits_per_word));
+	tx_count = min(tx_count, SSI_FIFO_DEPTH);
+
+	/* set fifo threshold */
+	val = readl(priv->base + SSI_FC);
+	val &= ~(SSI_FC_TXFTH_MASK | SSI_FC_RXFTH_MASK);
+	val |= FIELD_PREP(SSI_FC_TXFTH_MASK, tx_count);
+	val |= FIELD_PREP(SSI_FC_RXFTH_MASK, tx_count);
+	writel(val, priv->base + SSI_FC);
+
+	while (tx_count--)
+		uniphier_spi_send(priv);
+}
+
+static void uniphier_spi_set_cs(struct spi_device *spi, bool enable)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_FPS);
+
+	if (enable)
+		val |= SSI_FPS_FSPOL;
+	else
+		val &= ~SSI_FPS_FSPOL;
+
+	writel(val, priv->base + SSI_FPS);
+}
+
+static int uniphier_spi_transfer_one(struct spi_master *master,
+				     struct spi_device *spi,
+				     struct spi_transfer *t)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+	int status;
+
+	uniphier_spi_setup_transfer(spi, t);
+
+	reinit_completion(&priv->xfer_done);
+
+	uniphier_spi_fill_tx_fifo(priv);
+
+	uniphier_spi_irq_enable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
+
+	status = wait_for_completion_timeout(&priv->xfer_done,
+					     msecs_to_jiffies(SSI_TIMEOUT_MS));
+
+	uniphier_spi_irq_disable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
+
+	if (status < 0)
+		return status;
+
+	return priv->error;
+}
+
+static int uniphier_spi_prepare_transfer_hardware(struct spi_master *master)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+
+	writel(SSI_CTL_EN, priv->base + SSI_CTL);
+
+	return 0;
+}
+
+static int uniphier_spi_unprepare_transfer_hardware(struct spi_master *master)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+
+	writel(0, priv->base + SSI_CTL);
+
+	return 0;
+}
+
+static irqreturn_t uniphier_spi_handler(int irq, void *dev_id)
+{
+	struct uniphier_spi_priv *priv = dev_id;
+	u32 val, stat;
+
+	stat = readl(priv->base + SSI_IS);
+	val = SSI_IC_TCIC | SSI_IC_RCIC | SSI_IC_RORIC;
+	writel(val, priv->base + SSI_IC);
+
+	/* rx fifo overrun */
+	if (stat & SSI_IS_RORID) {
+		priv->error = -EIO;
+		goto done;
+	}
+
+	/* rx complete */
+	if ((stat & SSI_IS_RCID) && (stat & SSI_IS_RXRS)) {
+		while ((readl(priv->base + SSI_SR) & SSI_SR_RNE) &&
+				(priv->rx_bytes - priv->tx_bytes) > 0)
+			uniphier_spi_recv(priv);
+
+		if ((readl(priv->base + SSI_SR) & SSI_SR_RNE) ||
+				(priv->rx_bytes != priv->tx_bytes)) {
+			priv->error = -EIO;
+			goto done;
+		} else if (priv->rx_bytes == 0)
+			goto done;
+
+		/* next tx transfer */
+		uniphier_spi_fill_tx_fifo(priv);
+
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
+
+done:
+	complete(&priv->xfer_done);
+	return IRQ_HANDLED;
+}
+
+static int uniphier_spi_probe(struct platform_device *pdev)
+{
+	struct uniphier_spi_priv *priv;
+	struct spi_master *master;
+	struct resource *res;
+	unsigned long clk_rate;
+	int irq;
+	int ret;
+
+	master = spi_alloc_master(&pdev->dev, sizeof(*priv));
+	if (!master)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, master);
+
+	priv = spi_master_get_devdata(master);
+	priv->master = master;
+	priv->is_save_param = false;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(priv->base)) {
+		ret = PTR_ERR(priv->base);
+		goto out_master_put;
+	}
+
+	priv->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(priv->clk)) {
+		dev_err(&pdev->dev, "failed to get clock\n");
+		ret = PTR_ERR(priv->clk);
+		goto out_master_put;
+	}
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret)
+		goto out_master_put;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(&pdev->dev, "failed to get IRQ\n");
+		ret = irq;
+		goto out_disable_clk;
+	}
+
+	ret = devm_request_irq(&pdev->dev, irq, uniphier_spi_handler,
+			       0, "uniphier-spi", priv);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to request IRQ\n");
+		goto out_disable_clk;
+	}
+
+	init_completion(&priv->xfer_done);
+
+	clk_rate = clk_get_rate(priv->clk);
+
+	master->max_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MIN_CLK_DIVIDER);
+	master->min_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MAX_CLK_DIVIDER);
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
+	master->dev.of_node = pdev->dev.of_node;
+	master->bus_num = pdev->id;
+	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
+
+	master->set_cs = uniphier_spi_set_cs;
+	master->transfer_one = uniphier_spi_transfer_one;
+	master->prepare_transfer_hardware
+				= uniphier_spi_prepare_transfer_hardware;
+	master->unprepare_transfer_hardware
+				= uniphier_spi_unprepare_transfer_hardware;
+	master->num_chipselect = 1;
+
+	ret = devm_spi_register_master(&pdev->dev, master);
+	if (ret)
+		goto out_disable_clk;
+
+	return 0;
+
+out_disable_clk:
+	clk_disable_unprepare(priv->clk);
+
+out_master_put:
+	spi_master_put(master);
+	return ret;
+}
+
+static int uniphier_spi_remove(struct platform_device *pdev)
+{
+	struct uniphier_spi_priv *priv = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(priv->clk);
+
+	return 0;
+}
+
+static const struct of_device_id uniphier_spi_match[] = {
+	{ .compatible = "socionext,uniphier-scssi" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, uniphier_spi_match);
+
+static struct platform_driver uniphier_spi_driver = {
+	.probe = uniphier_spi_probe,
+	.remove = uniphier_spi_remove,
+	.driver = {
+		.name = "uniphier-spi",
+		.of_match_table = uniphier_spi_match,
+	},
+};
+module_platform_driver(uniphier_spi_driver);
+
+MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
+MODULE_AUTHOR("Keiji Hayashibara <hayashibara.keiji@socionext.com>");
+MODULE_DESCRIPTION("Socionext UniPhier SPI controller driver");
+MODULE_LICENSE("GPL v2");
-- 
2.18.0


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* Applied "spi: add SPI controller driver for UniPhier SoC" to the spi tree
@ 2018-08-01 11:20     ` Mark Brown
  0 siblings, 0 replies; 14+ messages in thread
From: Mark Brown @ 2018-08-01 11:20 UTC (permalink / raw)
  Cc: Kunihiko Hayashi, Mark Brown

The patch

   spi: add SPI controller driver for UniPhier SoC

has been applied to the spi tree at

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git 

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

>From 5ba155a4d4cc8e4cdd3db6df7d03271a3bd91177 Mon Sep 17 00:00:00 2001
From: Keiji Hayashibara <hayashibara.keiji@socionext.com>
Date: Wed, 1 Aug 2018 16:29:12 +0900
Subject: [PATCH] spi: add SPI controller driver for UniPhier SoC

Add SPI controller driver implemented in Socionext UniPhier SoCs.

UniPhier SoCs have two types SPI controllers; SCSSI supports a
single channel, and MCSSI supports multiple channels.
This driver supports SCSSI only.

This controller has 32bit TX/RX FIFO with depth of eight entry,
and supports the SPI master mode only.

This commit is implemented in PIO transfer mode, not DMA transfer.

Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Keiji Hayashibara <hayashibara.keiji@socionext.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 drivers/spi/Kconfig        |  13 +
 drivers/spi/Makefile       |   1 +
 drivers/spi/spi-uniphier.c | 525 +++++++++++++++++++++++++++++++++++++
 3 files changed, 539 insertions(+)
 create mode 100644 drivers/spi/spi-uniphier.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index ad5d68e1dab7..671d078349cc 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -688,6 +688,19 @@ config SPI_TXX9
 	help
 	  SPI driver for Toshiba TXx9 MIPS SoCs
 
+config SPI_UNIPHIER
+	tristate "Socionext UniPhier SPI Controller"
+	depends on (ARCH_UNIPHIER || COMPILE_TEST) && OF
+	help
+	  This enables a driver for the Socionext UniPhier SoC SCSSI SPI controller.
+
+	  UniPhier SoCs have SCSSI and MCSSI SPI controllers.
+	  Every UniPhier SoC has SCSSI which supports single channel.
+	  Older UniPhier Pro4/Pro5 also has MCSSI which support multiple channels.
+	  This driver supports SCSSI only.
+
+	  If your SoC supports SCSSI, say Y here.
+
 config SPI_XCOMM
 	tristate "Analog Devices AD-FMCOMMS1-EBZ SPI-I2C-bridge driver"
 	depends on I2C
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index cb1f4378b87c..a90d55970036 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -101,6 +101,7 @@ spi-thunderx-objs			:= spi-cavium.o spi-cavium-thunderx.o
 obj-$(CONFIG_SPI_THUNDERX)		+= spi-thunderx.o
 obj-$(CONFIG_SPI_TOPCLIFF_PCH)		+= spi-topcliff-pch.o
 obj-$(CONFIG_SPI_TXX9)			+= spi-txx9.o
+obj-$(CONFIG_SPI_UNIPHIER)		+= spi-uniphier.o
 obj-$(CONFIG_SPI_XCOMM)		+= spi-xcomm.o
 obj-$(CONFIG_SPI_XILINX)		+= spi-xilinx.o
 obj-$(CONFIG_SPI_XLP)			+= spi-xlp.o
diff --git a/drivers/spi/spi-uniphier.c b/drivers/spi/spi-uniphier.c
new file mode 100644
index 000000000000..089985465890
--- /dev/null
+++ b/drivers/spi/spi-uniphier.c
@@ -0,0 +1,525 @@
+// SPDX-License-Identifier: GPL-2.0
+// spi-uniphier.c - Socionext UniPhier SPI controller driver
+// Copyright 2012      Panasonic Corporation
+// Copyright 2016-2018 Socionext Inc.
+
+#include <linux/kernel.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+
+#include <asm/unaligned.h>
+
+#define SSI_TIMEOUT_MS		2000
+#define SSI_MAX_CLK_DIVIDER	254
+#define SSI_MIN_CLK_DIVIDER	4
+
+struct uniphier_spi_priv {
+	void __iomem *base;
+	struct clk *clk;
+	struct spi_master *master;
+	struct completion xfer_done;
+
+	int error;
+	unsigned int tx_bytes;
+	unsigned int rx_bytes;
+	const u8 *tx_buf;
+	u8 *rx_buf;
+
+	bool is_save_param;
+	u8 bits_per_word;
+	u16 mode;
+	u32 speed_hz;
+};
+
+#define SSI_CTL			0x00
+#define   SSI_CTL_EN		BIT(0)
+
+#define SSI_CKS			0x04
+#define   SSI_CKS_CKRAT_MASK	GENMASK(7, 0)
+#define   SSI_CKS_CKPHS		BIT(14)
+#define   SSI_CKS_CKINIT	BIT(13)
+#define   SSI_CKS_CKDLY		BIT(12)
+
+#define SSI_TXWDS		0x08
+#define   SSI_TXWDS_WDLEN_MASK	GENMASK(13, 8)
+#define   SSI_TXWDS_TDTF_MASK	GENMASK(7, 6)
+#define   SSI_TXWDS_DTLEN_MASK	GENMASK(5, 0)
+
+#define SSI_RXWDS		0x0c
+#define   SSI_RXWDS_DTLEN_MASK	GENMASK(5, 0)
+
+#define SSI_FPS			0x10
+#define   SSI_FPS_FSPOL		BIT(15)
+#define   SSI_FPS_FSTRT		BIT(14)
+
+#define SSI_SR			0x14
+#define   SSI_SR_RNE		BIT(0)
+
+#define SSI_IE			0x18
+#define   SSI_IE_RCIE		BIT(3)
+#define   SSI_IE_RORIE		BIT(0)
+
+#define SSI_IS			0x1c
+#define   SSI_IS_RXRS		BIT(9)
+#define   SSI_IS_RCID		BIT(3)
+#define   SSI_IS_RORID		BIT(0)
+
+#define SSI_IC			0x1c
+#define   SSI_IC_TCIC		BIT(4)
+#define   SSI_IC_RCIC		BIT(3)
+#define   SSI_IC_RORIC		BIT(0)
+
+#define SSI_FC			0x20
+#define   SSI_FC_TXFFL		BIT(12)
+#define   SSI_FC_TXFTH_MASK	GENMASK(11, 8)
+#define   SSI_FC_RXFFL		BIT(4)
+#define   SSI_FC_RXFTH_MASK	GENMASK(3, 0)
+
+#define SSI_TXDR		0x24
+#define SSI_RXDR		0x24
+
+#define SSI_FIFO_DEPTH		8U
+
+static inline unsigned int bytes_per_word(unsigned int bits)
+{
+	return bits <= 8 ? 1 : (bits <= 16 ? 2 : 4);
+}
+
+static inline void uniphier_spi_irq_enable(struct spi_device *spi, u32 mask)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_IE);
+	val |= mask;
+	writel(val, priv->base + SSI_IE);
+}
+
+static inline void uniphier_spi_irq_disable(struct spi_device *spi, u32 mask)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_IE);
+	val &= ~mask;
+	writel(val, priv->base + SSI_IE);
+}
+
+static void uniphier_spi_set_mode(struct spi_device *spi)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val1, val2;
+
+	/*
+	 * clock setting
+	 * CKPHS    capture timing. 0:rising edge, 1:falling edge
+	 * CKINIT   clock initial level. 0:low, 1:high
+	 * CKDLY    clock delay. 0:no delay, 1:delay depending on FSTRT
+	 *          (FSTRT=0: 1 clock, FSTRT=1: 0.5 clock)
+	 *
+	 * frame setting
+	 * FSPOL    frame signal porarity. 0: low, 1: high
+	 * FSTRT    start frame timing
+	 *          0: rising edge of clock, 1: falling edge of clock
+	 */
+	switch (spi->mode & (SPI_CPOL | SPI_CPHA)) {
+	case SPI_MODE_0:
+		/* CKPHS=1, CKINIT=0, CKDLY=1, FSTRT=0 */
+		val1 = SSI_CKS_CKPHS | SSI_CKS_CKDLY;
+		val2 = 0;
+		break;
+	case SPI_MODE_1:
+		/* CKPHS=0, CKINIT=0, CKDLY=0, FSTRT=1 */
+		val1 = 0;
+		val2 = SSI_FPS_FSTRT;
+		break;
+	case SPI_MODE_2:
+		/* CKPHS=0, CKINIT=1, CKDLY=1, FSTRT=1 */
+		val1 = SSI_CKS_CKINIT | SSI_CKS_CKDLY;
+		val2 = SSI_FPS_FSTRT;
+		break;
+	case SPI_MODE_3:
+		/* CKPHS=1, CKINIT=1, CKDLY=0, FSTRT=0 */
+		val1 = SSI_CKS_CKPHS | SSI_CKS_CKINIT;
+		val2 = 0;
+		break;
+	}
+
+	if (!(spi->mode & SPI_CS_HIGH))
+		val2 |= SSI_FPS_FSPOL;
+
+	writel(val1, priv->base + SSI_CKS);
+	writel(val2, priv->base + SSI_FPS);
+
+	val1 = 0;
+	if (spi->mode & SPI_LSB_FIRST)
+		val1 |= FIELD_PREP(SSI_TXWDS_TDTF_MASK, 1);
+	writel(val1, priv->base + SSI_TXWDS);
+	writel(val1, priv->base + SSI_RXWDS);
+}
+
+static void uniphier_spi_set_transfer_size(struct spi_device *spi, int size)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_TXWDS);
+	val &= ~(SSI_TXWDS_WDLEN_MASK | SSI_TXWDS_DTLEN_MASK);
+	val |= FIELD_PREP(SSI_TXWDS_WDLEN_MASK, size);
+	val |= FIELD_PREP(SSI_TXWDS_DTLEN_MASK, size);
+	writel(val, priv->base + SSI_TXWDS);
+
+	val = readl(priv->base + SSI_RXWDS);
+	val &= ~SSI_RXWDS_DTLEN_MASK;
+	val |= FIELD_PREP(SSI_RXWDS_DTLEN_MASK, size);
+	writel(val, priv->base + SSI_RXWDS);
+}
+
+static void uniphier_spi_set_baudrate(struct spi_device *spi,
+				      unsigned int speed)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val, ckdiv;
+
+	/*
+	 * the supported rates are even numbers from 4 to 254. (4,6,8...254)
+	 * round up as we look for equal or less speed
+	 */
+	ckdiv = DIV_ROUND_UP(clk_get_rate(priv->clk), speed);
+	ckdiv = round_up(ckdiv, 2);
+
+	val = readl(priv->base + SSI_CKS);
+	val &= ~SSI_CKS_CKRAT_MASK;
+	val |= ckdiv & SSI_CKS_CKRAT_MASK;
+	writel(val, priv->base + SSI_CKS);
+}
+
+static void uniphier_spi_setup_transfer(struct spi_device *spi,
+				       struct spi_transfer *t)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	priv->error = 0;
+	priv->tx_buf = t->tx_buf;
+	priv->rx_buf = t->rx_buf;
+	priv->tx_bytes = priv->rx_bytes = t->len;
+
+	if (!priv->is_save_param || priv->mode != spi->mode) {
+		uniphier_spi_set_mode(spi);
+		priv->mode = spi->mode;
+	}
+
+	if (!priv->is_save_param || priv->bits_per_word != t->bits_per_word) {
+		uniphier_spi_set_transfer_size(spi, t->bits_per_word);
+		priv->bits_per_word = t->bits_per_word;
+	}
+
+	if (!priv->is_save_param || priv->speed_hz != t->speed_hz) {
+		uniphier_spi_set_baudrate(spi, t->speed_hz);
+		priv->speed_hz = t->speed_hz;
+	}
+
+	if (!priv->is_save_param)
+		priv->is_save_param = true;
+
+	/* reset FIFOs */
+	val = SSI_FC_TXFFL | SSI_FC_RXFFL;
+	writel(val, priv->base + SSI_FC);
+}
+
+static void uniphier_spi_send(struct uniphier_spi_priv *priv)
+{
+	int wsize;
+	u32 val = 0;
+
+	wsize = min(bytes_per_word(priv->bits_per_word), priv->tx_bytes);
+	priv->tx_bytes -= wsize;
+
+	if (priv->tx_buf) {
+		switch (wsize) {
+		case 1:
+			val = *priv->tx_buf;
+			break;
+		case 2:
+			val = get_unaligned_le16(priv->tx_buf);
+			break;
+		case 4:
+			val = get_unaligned_le32(priv->tx_buf);
+			break;
+		}
+
+		priv->tx_buf += wsize;
+	}
+
+	writel(val, priv->base + SSI_TXDR);
+}
+
+static void uniphier_spi_recv(struct uniphier_spi_priv *priv)
+{
+	int rsize;
+	u32 val;
+
+	rsize = min(bytes_per_word(priv->bits_per_word), priv->rx_bytes);
+	priv->rx_bytes -= rsize;
+
+	val = readl(priv->base + SSI_RXDR);
+
+	if (priv->rx_buf) {
+		switch (rsize) {
+		case 1:
+			*priv->rx_buf = val;
+			break;
+		case 2:
+			put_unaligned_le16(val, priv->rx_buf);
+			break;
+		case 4:
+			put_unaligned_le32(val, priv->rx_buf);
+			break;
+		}
+
+		priv->rx_buf += rsize;
+	}
+}
+
+static void uniphier_spi_fill_tx_fifo(struct uniphier_spi_priv *priv)
+{
+	unsigned int tx_count;
+	u32 val;
+
+	tx_count = DIV_ROUND_UP(priv->tx_bytes,
+				bytes_per_word(priv->bits_per_word));
+	tx_count = min(tx_count, SSI_FIFO_DEPTH);
+
+	/* set fifo threshold */
+	val = readl(priv->base + SSI_FC);
+	val &= ~(SSI_FC_TXFTH_MASK | SSI_FC_RXFTH_MASK);
+	val |= FIELD_PREP(SSI_FC_TXFTH_MASK, tx_count);
+	val |= FIELD_PREP(SSI_FC_RXFTH_MASK, tx_count);
+	writel(val, priv->base + SSI_FC);
+
+	while (tx_count--)
+		uniphier_spi_send(priv);
+}
+
+static void uniphier_spi_set_cs(struct spi_device *spi, bool enable)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_FPS);
+
+	if (enable)
+		val |= SSI_FPS_FSPOL;
+	else
+		val &= ~SSI_FPS_FSPOL;
+
+	writel(val, priv->base + SSI_FPS);
+}
+
+static int uniphier_spi_transfer_one(struct spi_master *master,
+				     struct spi_device *spi,
+				     struct spi_transfer *t)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+	int status;
+
+	uniphier_spi_setup_transfer(spi, t);
+
+	reinit_completion(&priv->xfer_done);
+
+	uniphier_spi_fill_tx_fifo(priv);
+
+	uniphier_spi_irq_enable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
+
+	status = wait_for_completion_timeout(&priv->xfer_done,
+					     msecs_to_jiffies(SSI_TIMEOUT_MS));
+
+	uniphier_spi_irq_disable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
+
+	if (status < 0)
+		return status;
+
+	return priv->error;
+}
+
+static int uniphier_spi_prepare_transfer_hardware(struct spi_master *master)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+
+	writel(SSI_CTL_EN, priv->base + SSI_CTL);
+
+	return 0;
+}
+
+static int uniphier_spi_unprepare_transfer_hardware(struct spi_master *master)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+
+	writel(0, priv->base + SSI_CTL);
+
+	return 0;
+}
+
+static irqreturn_t uniphier_spi_handler(int irq, void *dev_id)
+{
+	struct uniphier_spi_priv *priv = dev_id;
+	u32 val, stat;
+
+	stat = readl(priv->base + SSI_IS);
+	val = SSI_IC_TCIC | SSI_IC_RCIC | SSI_IC_RORIC;
+	writel(val, priv->base + SSI_IC);
+
+	/* rx fifo overrun */
+	if (stat & SSI_IS_RORID) {
+		priv->error = -EIO;
+		goto done;
+	}
+
+	/* rx complete */
+	if ((stat & SSI_IS_RCID) && (stat & SSI_IS_RXRS)) {
+		while ((readl(priv->base + SSI_SR) & SSI_SR_RNE) &&
+				(priv->rx_bytes - priv->tx_bytes) > 0)
+			uniphier_spi_recv(priv);
+
+		if ((readl(priv->base + SSI_SR) & SSI_SR_RNE) ||
+				(priv->rx_bytes != priv->tx_bytes)) {
+			priv->error = -EIO;
+			goto done;
+		} else if (priv->rx_bytes == 0)
+			goto done;
+
+		/* next tx transfer */
+		uniphier_spi_fill_tx_fifo(priv);
+
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
+
+done:
+	complete(&priv->xfer_done);
+	return IRQ_HANDLED;
+}
+
+static int uniphier_spi_probe(struct platform_device *pdev)
+{
+	struct uniphier_spi_priv *priv;
+	struct spi_master *master;
+	struct resource *res;
+	unsigned long clk_rate;
+	int irq;
+	int ret;
+
+	master = spi_alloc_master(&pdev->dev, sizeof(*priv));
+	if (!master)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, master);
+
+	priv = spi_master_get_devdata(master);
+	priv->master = master;
+	priv->is_save_param = false;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(priv->base)) {
+		ret = PTR_ERR(priv->base);
+		goto out_master_put;
+	}
+
+	priv->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(priv->clk)) {
+		dev_err(&pdev->dev, "failed to get clock\n");
+		ret = PTR_ERR(priv->clk);
+		goto out_master_put;
+	}
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret)
+		goto out_master_put;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(&pdev->dev, "failed to get IRQ\n");
+		ret = irq;
+		goto out_disable_clk;
+	}
+
+	ret = devm_request_irq(&pdev->dev, irq, uniphier_spi_handler,
+			       0, "uniphier-spi", priv);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to request IRQ\n");
+		goto out_disable_clk;
+	}
+
+	init_completion(&priv->xfer_done);
+
+	clk_rate = clk_get_rate(priv->clk);
+
+	master->max_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MIN_CLK_DIVIDER);
+	master->min_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MAX_CLK_DIVIDER);
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
+	master->dev.of_node = pdev->dev.of_node;
+	master->bus_num = pdev->id;
+	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
+
+	master->set_cs = uniphier_spi_set_cs;
+	master->transfer_one = uniphier_spi_transfer_one;
+	master->prepare_transfer_hardware
+				= uniphier_spi_prepare_transfer_hardware;
+	master->unprepare_transfer_hardware
+				= uniphier_spi_unprepare_transfer_hardware;
+	master->num_chipselect = 1;
+
+	ret = devm_spi_register_master(&pdev->dev, master);
+	if (ret)
+		goto out_disable_clk;
+
+	return 0;
+
+out_disable_clk:
+	clk_disable_unprepare(priv->clk);
+
+out_master_put:
+	spi_master_put(master);
+	return ret;
+}
+
+static int uniphier_spi_remove(struct platform_device *pdev)
+{
+	struct uniphier_spi_priv *priv = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(priv->clk);
+
+	return 0;
+}
+
+static const struct of_device_id uniphier_spi_match[] = {
+	{ .compatible = "socionext,uniphier-scssi" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, uniphier_spi_match);
+
+static struct platform_driver uniphier_spi_driver = {
+	.probe = uniphier_spi_probe,
+	.remove = uniphier_spi_remove,
+	.driver = {
+		.name = "uniphier-spi",
+		.of_match_table = uniphier_spi_match,
+	},
+};
+module_platform_driver(uniphier_spi_driver);
+
+MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
+MODULE_AUTHOR("Keiji Hayashibara <hayashibara.keiji@socionext.com>");
+MODULE_DESCRIPTION("Socionext UniPhier SPI controller driver");
+MODULE_LICENSE("GPL v2");
-- 
2.18.0

^ permalink raw reply related	[flat|nested] 14+ messages in thread

* Applied "spi: add SPI controller driver for UniPhier SoC" to the spi tree
@ 2018-08-01 11:20     ` Mark Brown
  0 siblings, 0 replies; 14+ messages in thread
From: Mark Brown @ 2018-08-01 11:20 UTC (permalink / raw)
  To: Keiji Hayashibara
  Cc: Kunihiko Hayashi, Mark Brown, broonie, robh+dt, mark.rutland,
	yamada.masahiro, linux-spi, linux-arm-kernel, devicetree,
	masami.hiramatsu, jaswinder.singh, linux-kernel,
	hayashibara.keiji, Kunihiko Hayashi, linux-spi

The patch

   spi: add SPI controller driver for UniPhier SoC

has been applied to the spi tree at

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git 

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

>From 5ba155a4d4cc8e4cdd3db6df7d03271a3bd91177 Mon Sep 17 00:00:00 2001
From: Keiji Hayashibara <hayashibara.keiji@socionext.com>
Date: Wed, 1 Aug 2018 16:29:12 +0900
Subject: [PATCH] spi: add SPI controller driver for UniPhier SoC

Add SPI controller driver implemented in Socionext UniPhier SoCs.

UniPhier SoCs have two types SPI controllers; SCSSI supports a
single channel, and MCSSI supports multiple channels.
This driver supports SCSSI only.

This controller has 32bit TX/RX FIFO with depth of eight entry,
and supports the SPI master mode only.

This commit is implemented in PIO transfer mode, not DMA transfer.

Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Keiji Hayashibara <hayashibara.keiji@socionext.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 drivers/spi/Kconfig        |  13 +
 drivers/spi/Makefile       |   1 +
 drivers/spi/spi-uniphier.c | 525 +++++++++++++++++++++++++++++++++++++
 3 files changed, 539 insertions(+)
 create mode 100644 drivers/spi/spi-uniphier.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index ad5d68e1dab7..671d078349cc 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -688,6 +688,19 @@ config SPI_TXX9
 	help
 	  SPI driver for Toshiba TXx9 MIPS SoCs
 
+config SPI_UNIPHIER
+	tristate "Socionext UniPhier SPI Controller"
+	depends on (ARCH_UNIPHIER || COMPILE_TEST) && OF
+	help
+	  This enables a driver for the Socionext UniPhier SoC SCSSI SPI controller.
+
+	  UniPhier SoCs have SCSSI and MCSSI SPI controllers.
+	  Every UniPhier SoC has SCSSI which supports single channel.
+	  Older UniPhier Pro4/Pro5 also has MCSSI which support multiple channels.
+	  This driver supports SCSSI only.
+
+	  If your SoC supports SCSSI, say Y here.
+
 config SPI_XCOMM
 	tristate "Analog Devices AD-FMCOMMS1-EBZ SPI-I2C-bridge driver"
 	depends on I2C
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index cb1f4378b87c..a90d55970036 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -101,6 +101,7 @@ spi-thunderx-objs			:= spi-cavium.o spi-cavium-thunderx.o
 obj-$(CONFIG_SPI_THUNDERX)		+= spi-thunderx.o
 obj-$(CONFIG_SPI_TOPCLIFF_PCH)		+= spi-topcliff-pch.o
 obj-$(CONFIG_SPI_TXX9)			+= spi-txx9.o
+obj-$(CONFIG_SPI_UNIPHIER)		+= spi-uniphier.o
 obj-$(CONFIG_SPI_XCOMM)		+= spi-xcomm.o
 obj-$(CONFIG_SPI_XILINX)		+= spi-xilinx.o
 obj-$(CONFIG_SPI_XLP)			+= spi-xlp.o
diff --git a/drivers/spi/spi-uniphier.c b/drivers/spi/spi-uniphier.c
new file mode 100644
index 000000000000..089985465890
--- /dev/null
+++ b/drivers/spi/spi-uniphier.c
@@ -0,0 +1,525 @@
+// SPDX-License-Identifier: GPL-2.0
+// spi-uniphier.c - Socionext UniPhier SPI controller driver
+// Copyright 2012      Panasonic Corporation
+// Copyright 2016-2018 Socionext Inc.
+
+#include <linux/kernel.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+
+#include <asm/unaligned.h>
+
+#define SSI_TIMEOUT_MS		2000
+#define SSI_MAX_CLK_DIVIDER	254
+#define SSI_MIN_CLK_DIVIDER	4
+
+struct uniphier_spi_priv {
+	void __iomem *base;
+	struct clk *clk;
+	struct spi_master *master;
+	struct completion xfer_done;
+
+	int error;
+	unsigned int tx_bytes;
+	unsigned int rx_bytes;
+	const u8 *tx_buf;
+	u8 *rx_buf;
+
+	bool is_save_param;
+	u8 bits_per_word;
+	u16 mode;
+	u32 speed_hz;
+};
+
+#define SSI_CTL			0x00
+#define   SSI_CTL_EN		BIT(0)
+
+#define SSI_CKS			0x04
+#define   SSI_CKS_CKRAT_MASK	GENMASK(7, 0)
+#define   SSI_CKS_CKPHS		BIT(14)
+#define   SSI_CKS_CKINIT	BIT(13)
+#define   SSI_CKS_CKDLY		BIT(12)
+
+#define SSI_TXWDS		0x08
+#define   SSI_TXWDS_WDLEN_MASK	GENMASK(13, 8)
+#define   SSI_TXWDS_TDTF_MASK	GENMASK(7, 6)
+#define   SSI_TXWDS_DTLEN_MASK	GENMASK(5, 0)
+
+#define SSI_RXWDS		0x0c
+#define   SSI_RXWDS_DTLEN_MASK	GENMASK(5, 0)
+
+#define SSI_FPS			0x10
+#define   SSI_FPS_FSPOL		BIT(15)
+#define   SSI_FPS_FSTRT		BIT(14)
+
+#define SSI_SR			0x14
+#define   SSI_SR_RNE		BIT(0)
+
+#define SSI_IE			0x18
+#define   SSI_IE_RCIE		BIT(3)
+#define   SSI_IE_RORIE		BIT(0)
+
+#define SSI_IS			0x1c
+#define   SSI_IS_RXRS		BIT(9)
+#define   SSI_IS_RCID		BIT(3)
+#define   SSI_IS_RORID		BIT(0)
+
+#define SSI_IC			0x1c
+#define   SSI_IC_TCIC		BIT(4)
+#define   SSI_IC_RCIC		BIT(3)
+#define   SSI_IC_RORIC		BIT(0)
+
+#define SSI_FC			0x20
+#define   SSI_FC_TXFFL		BIT(12)
+#define   SSI_FC_TXFTH_MASK	GENMASK(11, 8)
+#define   SSI_FC_RXFFL		BIT(4)
+#define   SSI_FC_RXFTH_MASK	GENMASK(3, 0)
+
+#define SSI_TXDR		0x24
+#define SSI_RXDR		0x24
+
+#define SSI_FIFO_DEPTH		8U
+
+static inline unsigned int bytes_per_word(unsigned int bits)
+{
+	return bits <= 8 ? 1 : (bits <= 16 ? 2 : 4);
+}
+
+static inline void uniphier_spi_irq_enable(struct spi_device *spi, u32 mask)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_IE);
+	val |= mask;
+	writel(val, priv->base + SSI_IE);
+}
+
+static inline void uniphier_spi_irq_disable(struct spi_device *spi, u32 mask)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_IE);
+	val &= ~mask;
+	writel(val, priv->base + SSI_IE);
+}
+
+static void uniphier_spi_set_mode(struct spi_device *spi)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val1, val2;
+
+	/*
+	 * clock setting
+	 * CKPHS    capture timing. 0:rising edge, 1:falling edge
+	 * CKINIT   clock initial level. 0:low, 1:high
+	 * CKDLY    clock delay. 0:no delay, 1:delay depending on FSTRT
+	 *          (FSTRT=0: 1 clock, FSTRT=1: 0.5 clock)
+	 *
+	 * frame setting
+	 * FSPOL    frame signal porarity. 0: low, 1: high
+	 * FSTRT    start frame timing
+	 *          0: rising edge of clock, 1: falling edge of clock
+	 */
+	switch (spi->mode & (SPI_CPOL | SPI_CPHA)) {
+	case SPI_MODE_0:
+		/* CKPHS=1, CKINIT=0, CKDLY=1, FSTRT=0 */
+		val1 = SSI_CKS_CKPHS | SSI_CKS_CKDLY;
+		val2 = 0;
+		break;
+	case SPI_MODE_1:
+		/* CKPHS=0, CKINIT=0, CKDLY=0, FSTRT=1 */
+		val1 = 0;
+		val2 = SSI_FPS_FSTRT;
+		break;
+	case SPI_MODE_2:
+		/* CKPHS=0, CKINIT=1, CKDLY=1, FSTRT=1 */
+		val1 = SSI_CKS_CKINIT | SSI_CKS_CKDLY;
+		val2 = SSI_FPS_FSTRT;
+		break;
+	case SPI_MODE_3:
+		/* CKPHS=1, CKINIT=1, CKDLY=0, FSTRT=0 */
+		val1 = SSI_CKS_CKPHS | SSI_CKS_CKINIT;
+		val2 = 0;
+		break;
+	}
+
+	if (!(spi->mode & SPI_CS_HIGH))
+		val2 |= SSI_FPS_FSPOL;
+
+	writel(val1, priv->base + SSI_CKS);
+	writel(val2, priv->base + SSI_FPS);
+
+	val1 = 0;
+	if (spi->mode & SPI_LSB_FIRST)
+		val1 |= FIELD_PREP(SSI_TXWDS_TDTF_MASK, 1);
+	writel(val1, priv->base + SSI_TXWDS);
+	writel(val1, priv->base + SSI_RXWDS);
+}
+
+static void uniphier_spi_set_transfer_size(struct spi_device *spi, int size)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_TXWDS);
+	val &= ~(SSI_TXWDS_WDLEN_MASK | SSI_TXWDS_DTLEN_MASK);
+	val |= FIELD_PREP(SSI_TXWDS_WDLEN_MASK, size);
+	val |= FIELD_PREP(SSI_TXWDS_DTLEN_MASK, size);
+	writel(val, priv->base + SSI_TXWDS);
+
+	val = readl(priv->base + SSI_RXWDS);
+	val &= ~SSI_RXWDS_DTLEN_MASK;
+	val |= FIELD_PREP(SSI_RXWDS_DTLEN_MASK, size);
+	writel(val, priv->base + SSI_RXWDS);
+}
+
+static void uniphier_spi_set_baudrate(struct spi_device *spi,
+				      unsigned int speed)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val, ckdiv;
+
+	/*
+	 * the supported rates are even numbers from 4 to 254. (4,6,8...254)
+	 * round up as we look for equal or less speed
+	 */
+	ckdiv = DIV_ROUND_UP(clk_get_rate(priv->clk), speed);
+	ckdiv = round_up(ckdiv, 2);
+
+	val = readl(priv->base + SSI_CKS);
+	val &= ~SSI_CKS_CKRAT_MASK;
+	val |= ckdiv & SSI_CKS_CKRAT_MASK;
+	writel(val, priv->base + SSI_CKS);
+}
+
+static void uniphier_spi_setup_transfer(struct spi_device *spi,
+				       struct spi_transfer *t)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	priv->error = 0;
+	priv->tx_buf = t->tx_buf;
+	priv->rx_buf = t->rx_buf;
+	priv->tx_bytes = priv->rx_bytes = t->len;
+
+	if (!priv->is_save_param || priv->mode != spi->mode) {
+		uniphier_spi_set_mode(spi);
+		priv->mode = spi->mode;
+	}
+
+	if (!priv->is_save_param || priv->bits_per_word != t->bits_per_word) {
+		uniphier_spi_set_transfer_size(spi, t->bits_per_word);
+		priv->bits_per_word = t->bits_per_word;
+	}
+
+	if (!priv->is_save_param || priv->speed_hz != t->speed_hz) {
+		uniphier_spi_set_baudrate(spi, t->speed_hz);
+		priv->speed_hz = t->speed_hz;
+	}
+
+	if (!priv->is_save_param)
+		priv->is_save_param = true;
+
+	/* reset FIFOs */
+	val = SSI_FC_TXFFL | SSI_FC_RXFFL;
+	writel(val, priv->base + SSI_FC);
+}
+
+static void uniphier_spi_send(struct uniphier_spi_priv *priv)
+{
+	int wsize;
+	u32 val = 0;
+
+	wsize = min(bytes_per_word(priv->bits_per_word), priv->tx_bytes);
+	priv->tx_bytes -= wsize;
+
+	if (priv->tx_buf) {
+		switch (wsize) {
+		case 1:
+			val = *priv->tx_buf;
+			break;
+		case 2:
+			val = get_unaligned_le16(priv->tx_buf);
+			break;
+		case 4:
+			val = get_unaligned_le32(priv->tx_buf);
+			break;
+		}
+
+		priv->tx_buf += wsize;
+	}
+
+	writel(val, priv->base + SSI_TXDR);
+}
+
+static void uniphier_spi_recv(struct uniphier_spi_priv *priv)
+{
+	int rsize;
+	u32 val;
+
+	rsize = min(bytes_per_word(priv->bits_per_word), priv->rx_bytes);
+	priv->rx_bytes -= rsize;
+
+	val = readl(priv->base + SSI_RXDR);
+
+	if (priv->rx_buf) {
+		switch (rsize) {
+		case 1:
+			*priv->rx_buf = val;
+			break;
+		case 2:
+			put_unaligned_le16(val, priv->rx_buf);
+			break;
+		case 4:
+			put_unaligned_le32(val, priv->rx_buf);
+			break;
+		}
+
+		priv->rx_buf += rsize;
+	}
+}
+
+static void uniphier_spi_fill_tx_fifo(struct uniphier_spi_priv *priv)
+{
+	unsigned int tx_count;
+	u32 val;
+
+	tx_count = DIV_ROUND_UP(priv->tx_bytes,
+				bytes_per_word(priv->bits_per_word));
+	tx_count = min(tx_count, SSI_FIFO_DEPTH);
+
+	/* set fifo threshold */
+	val = readl(priv->base + SSI_FC);
+	val &= ~(SSI_FC_TXFTH_MASK | SSI_FC_RXFTH_MASK);
+	val |= FIELD_PREP(SSI_FC_TXFTH_MASK, tx_count);
+	val |= FIELD_PREP(SSI_FC_RXFTH_MASK, tx_count);
+	writel(val, priv->base + SSI_FC);
+
+	while (tx_count--)
+		uniphier_spi_send(priv);
+}
+
+static void uniphier_spi_set_cs(struct spi_device *spi, bool enable)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_FPS);
+
+	if (enable)
+		val |= SSI_FPS_FSPOL;
+	else
+		val &= ~SSI_FPS_FSPOL;
+
+	writel(val, priv->base + SSI_FPS);
+}
+
+static int uniphier_spi_transfer_one(struct spi_master *master,
+				     struct spi_device *spi,
+				     struct spi_transfer *t)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+	int status;
+
+	uniphier_spi_setup_transfer(spi, t);
+
+	reinit_completion(&priv->xfer_done);
+
+	uniphier_spi_fill_tx_fifo(priv);
+
+	uniphier_spi_irq_enable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
+
+	status = wait_for_completion_timeout(&priv->xfer_done,
+					     msecs_to_jiffies(SSI_TIMEOUT_MS));
+
+	uniphier_spi_irq_disable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
+
+	if (status < 0)
+		return status;
+
+	return priv->error;
+}
+
+static int uniphier_spi_prepare_transfer_hardware(struct spi_master *master)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+
+	writel(SSI_CTL_EN, priv->base + SSI_CTL);
+
+	return 0;
+}
+
+static int uniphier_spi_unprepare_transfer_hardware(struct spi_master *master)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+
+	writel(0, priv->base + SSI_CTL);
+
+	return 0;
+}
+
+static irqreturn_t uniphier_spi_handler(int irq, void *dev_id)
+{
+	struct uniphier_spi_priv *priv = dev_id;
+	u32 val, stat;
+
+	stat = readl(priv->base + SSI_IS);
+	val = SSI_IC_TCIC | SSI_IC_RCIC | SSI_IC_RORIC;
+	writel(val, priv->base + SSI_IC);
+
+	/* rx fifo overrun */
+	if (stat & SSI_IS_RORID) {
+		priv->error = -EIO;
+		goto done;
+	}
+
+	/* rx complete */
+	if ((stat & SSI_IS_RCID) && (stat & SSI_IS_RXRS)) {
+		while ((readl(priv->base + SSI_SR) & SSI_SR_RNE) &&
+				(priv->rx_bytes - priv->tx_bytes) > 0)
+			uniphier_spi_recv(priv);
+
+		if ((readl(priv->base + SSI_SR) & SSI_SR_RNE) ||
+				(priv->rx_bytes != priv->tx_bytes)) {
+			priv->error = -EIO;
+			goto done;
+		} else if (priv->rx_bytes == 0)
+			goto done;
+
+		/* next tx transfer */
+		uniphier_spi_fill_tx_fifo(priv);
+
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
+
+done:
+	complete(&priv->xfer_done);
+	return IRQ_HANDLED;
+}
+
+static int uniphier_spi_probe(struct platform_device *pdev)
+{
+	struct uniphier_spi_priv *priv;
+	struct spi_master *master;
+	struct resource *res;
+	unsigned long clk_rate;
+	int irq;
+	int ret;
+
+	master = spi_alloc_master(&pdev->dev, sizeof(*priv));
+	if (!master)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, master);
+
+	priv = spi_master_get_devdata(master);
+	priv->master = master;
+	priv->is_save_param = false;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(priv->base)) {
+		ret = PTR_ERR(priv->base);
+		goto out_master_put;
+	}
+
+	priv->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(priv->clk)) {
+		dev_err(&pdev->dev, "failed to get clock\n");
+		ret = PTR_ERR(priv->clk);
+		goto out_master_put;
+	}
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret)
+		goto out_master_put;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(&pdev->dev, "failed to get IRQ\n");
+		ret = irq;
+		goto out_disable_clk;
+	}
+
+	ret = devm_request_irq(&pdev->dev, irq, uniphier_spi_handler,
+			       0, "uniphier-spi", priv);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to request IRQ\n");
+		goto out_disable_clk;
+	}
+
+	init_completion(&priv->xfer_done);
+
+	clk_rate = clk_get_rate(priv->clk);
+
+	master->max_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MIN_CLK_DIVIDER);
+	master->min_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MAX_CLK_DIVIDER);
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
+	master->dev.of_node = pdev->dev.of_node;
+	master->bus_num = pdev->id;
+	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
+
+	master->set_cs = uniphier_spi_set_cs;
+	master->transfer_one = uniphier_spi_transfer_one;
+	master->prepare_transfer_hardware
+				= uniphier_spi_prepare_transfer_hardware;
+	master->unprepare_transfer_hardware
+				= uniphier_spi_unprepare_transfer_hardware;
+	master->num_chipselect = 1;
+
+	ret = devm_spi_register_master(&pdev->dev, master);
+	if (ret)
+		goto out_disable_clk;
+
+	return 0;
+
+out_disable_clk:
+	clk_disable_unprepare(priv->clk);
+
+out_master_put:
+	spi_master_put(master);
+	return ret;
+}
+
+static int uniphier_spi_remove(struct platform_device *pdev)
+{
+	struct uniphier_spi_priv *priv = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(priv->clk);
+
+	return 0;
+}
+
+static const struct of_device_id uniphier_spi_match[] = {
+	{ .compatible = "socionext,uniphier-scssi" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, uniphier_spi_match);
+
+static struct platform_driver uniphier_spi_driver = {
+	.probe = uniphier_spi_probe,
+	.remove = uniphier_spi_remove,
+	.driver = {
+		.name = "uniphier-spi",
+		.of_match_table = uniphier_spi_match,
+	},
+};
+module_platform_driver(uniphier_spi_driver);
+
+MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
+MODULE_AUTHOR("Keiji Hayashibara <hayashibara.keiji@socionext.com>");
+MODULE_DESCRIPTION("Socionext UniPhier SPI controller driver");
+MODULE_LICENSE("GPL v2");
-- 
2.18.0

^ permalink raw reply related	[flat|nested] 14+ messages in thread

* Applied "spi: add SPI controller driver for UniPhier SoC" to the spi tree
@ 2018-08-01 11:20     ` Mark Brown
  0 siblings, 0 replies; 14+ messages in thread
From: Mark Brown @ 2018-08-01 11:20 UTC (permalink / raw)
  To: linux-arm-kernel

The patch

   spi: add SPI controller driver for UniPhier SoC

has been applied to the spi tree at

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git 

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

>From 5ba155a4d4cc8e4cdd3db6df7d03271a3bd91177 Mon Sep 17 00:00:00 2001
From: Keiji Hayashibara <hayashibara.keiji@socionext.com>
Date: Wed, 1 Aug 2018 16:29:12 +0900
Subject: [PATCH] spi: add SPI controller driver for UniPhier SoC

Add SPI controller driver implemented in Socionext UniPhier SoCs.

UniPhier SoCs have two types SPI controllers; SCSSI supports a
single channel, and MCSSI supports multiple channels.
This driver supports SCSSI only.

This controller has 32bit TX/RX FIFO with depth of eight entry,
and supports the SPI master mode only.

This commit is implemented in PIO transfer mode, not DMA transfer.

Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Keiji Hayashibara <hayashibara.keiji@socionext.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 drivers/spi/Kconfig        |  13 +
 drivers/spi/Makefile       |   1 +
 drivers/spi/spi-uniphier.c | 525 +++++++++++++++++++++++++++++++++++++
 3 files changed, 539 insertions(+)
 create mode 100644 drivers/spi/spi-uniphier.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index ad5d68e1dab7..671d078349cc 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -688,6 +688,19 @@ config SPI_TXX9
 	help
 	  SPI driver for Toshiba TXx9 MIPS SoCs
 
+config SPI_UNIPHIER
+	tristate "Socionext UniPhier SPI Controller"
+	depends on (ARCH_UNIPHIER || COMPILE_TEST) && OF
+	help
+	  This enables a driver for the Socionext UniPhier SoC SCSSI SPI controller.
+
+	  UniPhier SoCs have SCSSI and MCSSI SPI controllers.
+	  Every UniPhier SoC has SCSSI which supports single channel.
+	  Older UniPhier Pro4/Pro5 also has MCSSI which support multiple channels.
+	  This driver supports SCSSI only.
+
+	  If your SoC supports SCSSI, say Y here.
+
 config SPI_XCOMM
 	tristate "Analog Devices AD-FMCOMMS1-EBZ SPI-I2C-bridge driver"
 	depends on I2C
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index cb1f4378b87c..a90d55970036 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -101,6 +101,7 @@ spi-thunderx-objs			:= spi-cavium.o spi-cavium-thunderx.o
 obj-$(CONFIG_SPI_THUNDERX)		+= spi-thunderx.o
 obj-$(CONFIG_SPI_TOPCLIFF_PCH)		+= spi-topcliff-pch.o
 obj-$(CONFIG_SPI_TXX9)			+= spi-txx9.o
+obj-$(CONFIG_SPI_UNIPHIER)		+= spi-uniphier.o
 obj-$(CONFIG_SPI_XCOMM)		+= spi-xcomm.o
 obj-$(CONFIG_SPI_XILINX)		+= spi-xilinx.o
 obj-$(CONFIG_SPI_XLP)			+= spi-xlp.o
diff --git a/drivers/spi/spi-uniphier.c b/drivers/spi/spi-uniphier.c
new file mode 100644
index 000000000000..089985465890
--- /dev/null
+++ b/drivers/spi/spi-uniphier.c
@@ -0,0 +1,525 @@
+// SPDX-License-Identifier: GPL-2.0
+// spi-uniphier.c - Socionext UniPhier SPI controller driver
+// Copyright 2012      Panasonic Corporation
+// Copyright 2016-2018 Socionext Inc.
+
+#include <linux/kernel.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+
+#include <asm/unaligned.h>
+
+#define SSI_TIMEOUT_MS		2000
+#define SSI_MAX_CLK_DIVIDER	254
+#define SSI_MIN_CLK_DIVIDER	4
+
+struct uniphier_spi_priv {
+	void __iomem *base;
+	struct clk *clk;
+	struct spi_master *master;
+	struct completion xfer_done;
+
+	int error;
+	unsigned int tx_bytes;
+	unsigned int rx_bytes;
+	const u8 *tx_buf;
+	u8 *rx_buf;
+
+	bool is_save_param;
+	u8 bits_per_word;
+	u16 mode;
+	u32 speed_hz;
+};
+
+#define SSI_CTL			0x00
+#define   SSI_CTL_EN		BIT(0)
+
+#define SSI_CKS			0x04
+#define   SSI_CKS_CKRAT_MASK	GENMASK(7, 0)
+#define   SSI_CKS_CKPHS		BIT(14)
+#define   SSI_CKS_CKINIT	BIT(13)
+#define   SSI_CKS_CKDLY		BIT(12)
+
+#define SSI_TXWDS		0x08
+#define   SSI_TXWDS_WDLEN_MASK	GENMASK(13, 8)
+#define   SSI_TXWDS_TDTF_MASK	GENMASK(7, 6)
+#define   SSI_TXWDS_DTLEN_MASK	GENMASK(5, 0)
+
+#define SSI_RXWDS		0x0c
+#define   SSI_RXWDS_DTLEN_MASK	GENMASK(5, 0)
+
+#define SSI_FPS			0x10
+#define   SSI_FPS_FSPOL		BIT(15)
+#define   SSI_FPS_FSTRT		BIT(14)
+
+#define SSI_SR			0x14
+#define   SSI_SR_RNE		BIT(0)
+
+#define SSI_IE			0x18
+#define   SSI_IE_RCIE		BIT(3)
+#define   SSI_IE_RORIE		BIT(0)
+
+#define SSI_IS			0x1c
+#define   SSI_IS_RXRS		BIT(9)
+#define   SSI_IS_RCID		BIT(3)
+#define   SSI_IS_RORID		BIT(0)
+
+#define SSI_IC			0x1c
+#define   SSI_IC_TCIC		BIT(4)
+#define   SSI_IC_RCIC		BIT(3)
+#define   SSI_IC_RORIC		BIT(0)
+
+#define SSI_FC			0x20
+#define   SSI_FC_TXFFL		BIT(12)
+#define   SSI_FC_TXFTH_MASK	GENMASK(11, 8)
+#define   SSI_FC_RXFFL		BIT(4)
+#define   SSI_FC_RXFTH_MASK	GENMASK(3, 0)
+
+#define SSI_TXDR		0x24
+#define SSI_RXDR		0x24
+
+#define SSI_FIFO_DEPTH		8U
+
+static inline unsigned int bytes_per_word(unsigned int bits)
+{
+	return bits <= 8 ? 1 : (bits <= 16 ? 2 : 4);
+}
+
+static inline void uniphier_spi_irq_enable(struct spi_device *spi, u32 mask)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_IE);
+	val |= mask;
+	writel(val, priv->base + SSI_IE);
+}
+
+static inline void uniphier_spi_irq_disable(struct spi_device *spi, u32 mask)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_IE);
+	val &= ~mask;
+	writel(val, priv->base + SSI_IE);
+}
+
+static void uniphier_spi_set_mode(struct spi_device *spi)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val1, val2;
+
+	/*
+	 * clock setting
+	 * CKPHS    capture timing. 0:rising edge, 1:falling edge
+	 * CKINIT   clock initial level. 0:low, 1:high
+	 * CKDLY    clock delay. 0:no delay, 1:delay depending on FSTRT
+	 *          (FSTRT=0: 1 clock, FSTRT=1: 0.5 clock)
+	 *
+	 * frame setting
+	 * FSPOL    frame signal porarity. 0: low, 1: high
+	 * FSTRT    start frame timing
+	 *          0: rising edge of clock, 1: falling edge of clock
+	 */
+	switch (spi->mode & (SPI_CPOL | SPI_CPHA)) {
+	case SPI_MODE_0:
+		/* CKPHS=1, CKINIT=0, CKDLY=1, FSTRT=0 */
+		val1 = SSI_CKS_CKPHS | SSI_CKS_CKDLY;
+		val2 = 0;
+		break;
+	case SPI_MODE_1:
+		/* CKPHS=0, CKINIT=0, CKDLY=0, FSTRT=1 */
+		val1 = 0;
+		val2 = SSI_FPS_FSTRT;
+		break;
+	case SPI_MODE_2:
+		/* CKPHS=0, CKINIT=1, CKDLY=1, FSTRT=1 */
+		val1 = SSI_CKS_CKINIT | SSI_CKS_CKDLY;
+		val2 = SSI_FPS_FSTRT;
+		break;
+	case SPI_MODE_3:
+		/* CKPHS=1, CKINIT=1, CKDLY=0, FSTRT=0 */
+		val1 = SSI_CKS_CKPHS | SSI_CKS_CKINIT;
+		val2 = 0;
+		break;
+	}
+
+	if (!(spi->mode & SPI_CS_HIGH))
+		val2 |= SSI_FPS_FSPOL;
+
+	writel(val1, priv->base + SSI_CKS);
+	writel(val2, priv->base + SSI_FPS);
+
+	val1 = 0;
+	if (spi->mode & SPI_LSB_FIRST)
+		val1 |= FIELD_PREP(SSI_TXWDS_TDTF_MASK, 1);
+	writel(val1, priv->base + SSI_TXWDS);
+	writel(val1, priv->base + SSI_RXWDS);
+}
+
+static void uniphier_spi_set_transfer_size(struct spi_device *spi, int size)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_TXWDS);
+	val &= ~(SSI_TXWDS_WDLEN_MASK | SSI_TXWDS_DTLEN_MASK);
+	val |= FIELD_PREP(SSI_TXWDS_WDLEN_MASK, size);
+	val |= FIELD_PREP(SSI_TXWDS_DTLEN_MASK, size);
+	writel(val, priv->base + SSI_TXWDS);
+
+	val = readl(priv->base + SSI_RXWDS);
+	val &= ~SSI_RXWDS_DTLEN_MASK;
+	val |= FIELD_PREP(SSI_RXWDS_DTLEN_MASK, size);
+	writel(val, priv->base + SSI_RXWDS);
+}
+
+static void uniphier_spi_set_baudrate(struct spi_device *spi,
+				      unsigned int speed)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val, ckdiv;
+
+	/*
+	 * the supported rates are even numbers from 4 to 254. (4,6,8...254)
+	 * round up as we look for equal or less speed
+	 */
+	ckdiv = DIV_ROUND_UP(clk_get_rate(priv->clk), speed);
+	ckdiv = round_up(ckdiv, 2);
+
+	val = readl(priv->base + SSI_CKS);
+	val &= ~SSI_CKS_CKRAT_MASK;
+	val |= ckdiv & SSI_CKS_CKRAT_MASK;
+	writel(val, priv->base + SSI_CKS);
+}
+
+static void uniphier_spi_setup_transfer(struct spi_device *spi,
+				       struct spi_transfer *t)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	priv->error = 0;
+	priv->tx_buf = t->tx_buf;
+	priv->rx_buf = t->rx_buf;
+	priv->tx_bytes = priv->rx_bytes = t->len;
+
+	if (!priv->is_save_param || priv->mode != spi->mode) {
+		uniphier_spi_set_mode(spi);
+		priv->mode = spi->mode;
+	}
+
+	if (!priv->is_save_param || priv->bits_per_word != t->bits_per_word) {
+		uniphier_spi_set_transfer_size(spi, t->bits_per_word);
+		priv->bits_per_word = t->bits_per_word;
+	}
+
+	if (!priv->is_save_param || priv->speed_hz != t->speed_hz) {
+		uniphier_spi_set_baudrate(spi, t->speed_hz);
+		priv->speed_hz = t->speed_hz;
+	}
+
+	if (!priv->is_save_param)
+		priv->is_save_param = true;
+
+	/* reset FIFOs */
+	val = SSI_FC_TXFFL | SSI_FC_RXFFL;
+	writel(val, priv->base + SSI_FC);
+}
+
+static void uniphier_spi_send(struct uniphier_spi_priv *priv)
+{
+	int wsize;
+	u32 val = 0;
+
+	wsize = min(bytes_per_word(priv->bits_per_word), priv->tx_bytes);
+	priv->tx_bytes -= wsize;
+
+	if (priv->tx_buf) {
+		switch (wsize) {
+		case 1:
+			val = *priv->tx_buf;
+			break;
+		case 2:
+			val = get_unaligned_le16(priv->tx_buf);
+			break;
+		case 4:
+			val = get_unaligned_le32(priv->tx_buf);
+			break;
+		}
+
+		priv->tx_buf += wsize;
+	}
+
+	writel(val, priv->base + SSI_TXDR);
+}
+
+static void uniphier_spi_recv(struct uniphier_spi_priv *priv)
+{
+	int rsize;
+	u32 val;
+
+	rsize = min(bytes_per_word(priv->bits_per_word), priv->rx_bytes);
+	priv->rx_bytes -= rsize;
+
+	val = readl(priv->base + SSI_RXDR);
+
+	if (priv->rx_buf) {
+		switch (rsize) {
+		case 1:
+			*priv->rx_buf = val;
+			break;
+		case 2:
+			put_unaligned_le16(val, priv->rx_buf);
+			break;
+		case 4:
+			put_unaligned_le32(val, priv->rx_buf);
+			break;
+		}
+
+		priv->rx_buf += rsize;
+	}
+}
+
+static void uniphier_spi_fill_tx_fifo(struct uniphier_spi_priv *priv)
+{
+	unsigned int tx_count;
+	u32 val;
+
+	tx_count = DIV_ROUND_UP(priv->tx_bytes,
+				bytes_per_word(priv->bits_per_word));
+	tx_count = min(tx_count, SSI_FIFO_DEPTH);
+
+	/* set fifo threshold */
+	val = readl(priv->base + SSI_FC);
+	val &= ~(SSI_FC_TXFTH_MASK | SSI_FC_RXFTH_MASK);
+	val |= FIELD_PREP(SSI_FC_TXFTH_MASK, tx_count);
+	val |= FIELD_PREP(SSI_FC_RXFTH_MASK, tx_count);
+	writel(val, priv->base + SSI_FC);
+
+	while (tx_count--)
+		uniphier_spi_send(priv);
+}
+
+static void uniphier_spi_set_cs(struct spi_device *spi, bool enable)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
+	u32 val;
+
+	val = readl(priv->base + SSI_FPS);
+
+	if (enable)
+		val |= SSI_FPS_FSPOL;
+	else
+		val &= ~SSI_FPS_FSPOL;
+
+	writel(val, priv->base + SSI_FPS);
+}
+
+static int uniphier_spi_transfer_one(struct spi_master *master,
+				     struct spi_device *spi,
+				     struct spi_transfer *t)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+	int status;
+
+	uniphier_spi_setup_transfer(spi, t);
+
+	reinit_completion(&priv->xfer_done);
+
+	uniphier_spi_fill_tx_fifo(priv);
+
+	uniphier_spi_irq_enable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
+
+	status = wait_for_completion_timeout(&priv->xfer_done,
+					     msecs_to_jiffies(SSI_TIMEOUT_MS));
+
+	uniphier_spi_irq_disable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
+
+	if (status < 0)
+		return status;
+
+	return priv->error;
+}
+
+static int uniphier_spi_prepare_transfer_hardware(struct spi_master *master)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+
+	writel(SSI_CTL_EN, priv->base + SSI_CTL);
+
+	return 0;
+}
+
+static int uniphier_spi_unprepare_transfer_hardware(struct spi_master *master)
+{
+	struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+
+	writel(0, priv->base + SSI_CTL);
+
+	return 0;
+}
+
+static irqreturn_t uniphier_spi_handler(int irq, void *dev_id)
+{
+	struct uniphier_spi_priv *priv = dev_id;
+	u32 val, stat;
+
+	stat = readl(priv->base + SSI_IS);
+	val = SSI_IC_TCIC | SSI_IC_RCIC | SSI_IC_RORIC;
+	writel(val, priv->base + SSI_IC);
+
+	/* rx fifo overrun */
+	if (stat & SSI_IS_RORID) {
+		priv->error = -EIO;
+		goto done;
+	}
+
+	/* rx complete */
+	if ((stat & SSI_IS_RCID) && (stat & SSI_IS_RXRS)) {
+		while ((readl(priv->base + SSI_SR) & SSI_SR_RNE) &&
+				(priv->rx_bytes - priv->tx_bytes) > 0)
+			uniphier_spi_recv(priv);
+
+		if ((readl(priv->base + SSI_SR) & SSI_SR_RNE) ||
+				(priv->rx_bytes != priv->tx_bytes)) {
+			priv->error = -EIO;
+			goto done;
+		} else if (priv->rx_bytes == 0)
+			goto done;
+
+		/* next tx transfer */
+		uniphier_spi_fill_tx_fifo(priv);
+
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
+
+done:
+	complete(&priv->xfer_done);
+	return IRQ_HANDLED;
+}
+
+static int uniphier_spi_probe(struct platform_device *pdev)
+{
+	struct uniphier_spi_priv *priv;
+	struct spi_master *master;
+	struct resource *res;
+	unsigned long clk_rate;
+	int irq;
+	int ret;
+
+	master = spi_alloc_master(&pdev->dev, sizeof(*priv));
+	if (!master)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, master);
+
+	priv = spi_master_get_devdata(master);
+	priv->master = master;
+	priv->is_save_param = false;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(priv->base)) {
+		ret = PTR_ERR(priv->base);
+		goto out_master_put;
+	}
+
+	priv->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(priv->clk)) {
+		dev_err(&pdev->dev, "failed to get clock\n");
+		ret = PTR_ERR(priv->clk);
+		goto out_master_put;
+	}
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret)
+		goto out_master_put;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(&pdev->dev, "failed to get IRQ\n");
+		ret = irq;
+		goto out_disable_clk;
+	}
+
+	ret = devm_request_irq(&pdev->dev, irq, uniphier_spi_handler,
+			       0, "uniphier-spi", priv);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to request IRQ\n");
+		goto out_disable_clk;
+	}
+
+	init_completion(&priv->xfer_done);
+
+	clk_rate = clk_get_rate(priv->clk);
+
+	master->max_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MIN_CLK_DIVIDER);
+	master->min_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MAX_CLK_DIVIDER);
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
+	master->dev.of_node = pdev->dev.of_node;
+	master->bus_num = pdev->id;
+	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
+
+	master->set_cs = uniphier_spi_set_cs;
+	master->transfer_one = uniphier_spi_transfer_one;
+	master->prepare_transfer_hardware
+				= uniphier_spi_prepare_transfer_hardware;
+	master->unprepare_transfer_hardware
+				= uniphier_spi_unprepare_transfer_hardware;
+	master->num_chipselect = 1;
+
+	ret = devm_spi_register_master(&pdev->dev, master);
+	if (ret)
+		goto out_disable_clk;
+
+	return 0;
+
+out_disable_clk:
+	clk_disable_unprepare(priv->clk);
+
+out_master_put:
+	spi_master_put(master);
+	return ret;
+}
+
+static int uniphier_spi_remove(struct platform_device *pdev)
+{
+	struct uniphier_spi_priv *priv = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(priv->clk);
+
+	return 0;
+}
+
+static const struct of_device_id uniphier_spi_match[] = {
+	{ .compatible = "socionext,uniphier-scssi" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, uniphier_spi_match);
+
+static struct platform_driver uniphier_spi_driver = {
+	.probe = uniphier_spi_probe,
+	.remove = uniphier_spi_remove,
+	.driver = {
+		.name = "uniphier-spi",
+		.of_match_table = uniphier_spi_match,
+	},
+};
+module_platform_driver(uniphier_spi_driver);
+
+MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
+MODULE_AUTHOR("Keiji Hayashibara <hayashibara.keiji@socionext.com>");
+MODULE_DESCRIPTION("Socionext UniPhier SPI controller driver");
+MODULE_LICENSE("GPL v2");
-- 
2.18.0

^ permalink raw reply related	[flat|nested] 14+ messages in thread

* RE: [PATCH v3 2/2] spi: add SPI controller driver for UniPhier SoC
  2018-08-01 10:20     ` Andy Shevchenko
@ 2018-08-02  7:52       ` Keiji Hayashibara
  -1 siblings, 0 replies; 14+ messages in thread
From: Keiji Hayashibara @ 2018-08-02  7:52 UTC (permalink / raw)
  To: 'Andy Shevchenko'
  Cc: Mark Brown, Rob Herring, Mark Rutland, Yamada,
	Masahiro/山田 真弘,
	linux-spi, linux-arm Mailing List, devicetree, Masami Hiramatsu,
	Jassi Brar, Linux Kernel Mailing List, Hayashi,
	Kunihiko/林 邦彦

Hi Andy,

Thank you for your check.


> From: Andy Shevchenko [mailto:andy.shevchenko@gmail.com]
> Sent: Wednesday, August 1, 2018 7:21 PM
> To: Hayashibara, Keiji/林原 啓二 <hayashibara.keiji@socionext.com>
> Subject: Re: [PATCH v3 2/2] spi: add SPI controller driver for UniPhier SoC
> 
> On Wed, Aug 1, 2018 at 10:29 AM, Keiji Hayashibara <hayashibara.keiji@socionext.com> wrote:
> > Add SPI controller driver implemented in Socionext UniPhier SoCs.
> >
> > UniPhier SoCs have two types SPI controllers; SCSSI supports a single
> > channel, and MCSSI supports multiple channels.
> > This driver supports SCSSI only.
> >
> > This controller has 32bit TX/RX FIFO with depth of eight entry, and
> > supports the SPI master mode only.
> >
> > This commit is implemented in PIO transfer mode, not DMA transfer.
> >
> 
> One comment below, otherwise FWIW,
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> 
> 
> > Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
> > Signed-off-by: Keiji Hayashibara <hayashibara.keiji@socionext.com>
> > ---
> >  drivers/spi/Kconfig        |  13 ++
> >  drivers/spi/Makefile       |   1 +
> >  drivers/spi/spi-uniphier.c | 525
> > +++++++++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 539 insertions(+)
> >  create mode 100644 drivers/spi/spi-uniphier.c
> >
> > diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index
> > ad5d68e..671d078 100644
> > --- a/drivers/spi/Kconfig
> > +++ b/drivers/spi/Kconfig
> > @@ -688,6 +688,19 @@ config SPI_TXX9
> >         help
> >           SPI driver for Toshiba TXx9 MIPS SoCs
> >
> > +config SPI_UNIPHIER
> > +       tristate "Socionext UniPhier SPI Controller"
> > +       depends on (ARCH_UNIPHIER || COMPILE_TEST) && OF
> > +       help
> > +         This enables a driver for the Socionext UniPhier SoC SCSSI SPI controller.
> > +
> > +         UniPhier SoCs have SCSSI and MCSSI SPI controllers.
> > +         Every UniPhier SoC has SCSSI which supports single channel.
> > +         Older UniPhier Pro4/Pro5 also has MCSSI which support multiple channels.
> > +         This driver supports SCSSI only.
> > +
> > +         If your SoC supports SCSSI, say Y here.
> > +
> >  config SPI_XCOMM
> >         tristate "Analog Devices AD-FMCOMMS1-EBZ SPI-I2C-bridge driver"
> >         depends on I2C
> > diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index
> > cb1f437..a90d559 100644
> > --- a/drivers/spi/Makefile
> > +++ b/drivers/spi/Makefile
> > @@ -101,6 +101,7 @@ spi-thunderx-objs                   := spi-cavium.o spi-cavium-thunderx.o
> >  obj-$(CONFIG_SPI_THUNDERX)             += spi-thunderx.o
> >  obj-$(CONFIG_SPI_TOPCLIFF_PCH)         += spi-topcliff-pch.o
> >  obj-$(CONFIG_SPI_TXX9)                 += spi-txx9.o
> > +obj-$(CONFIG_SPI_UNIPHIER)             += spi-uniphier.o
> >  obj-$(CONFIG_SPI_XCOMM)                += spi-xcomm.o
> >  obj-$(CONFIG_SPI_XILINX)               += spi-xilinx.o
> >  obj-$(CONFIG_SPI_XLP)                  += spi-xlp.o
> > diff --git a/drivers/spi/spi-uniphier.c b/drivers/spi/spi-uniphier.c
> > new file mode 100644 index 0000000..0899854
> > --- /dev/null
> > +++ b/drivers/spi/spi-uniphier.c
> > @@ -0,0 +1,525 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +// spi-uniphier.c - Socionext UniPhier SPI controller driver
> > +// Copyright 2012      Panasonic Corporation
> > +// Copyright 2016-2018 Socionext Inc.
> > +
> > +#include <linux/kernel.h>
> > +#include <linux/bitfield.h>
> > +#include <linux/bitops.h>
> > +#include <linux/clk.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/io.h>
> > +#include <linux/module.h>
> 
> > +#include <linux/of.h>
> > +#include <linux/of_platform.h>
> 
> I fail to find where those two are used, just remove them.

I sent this modification as a new patch.
https://patchwork.kernel.org/patch/10553249/


> > +#include <linux/platform_device.h>
> > +#include <linux/spi/spi.h>
> > +
> > +#include <asm/unaligned.h>
> > +
> > +#define SSI_TIMEOUT_MS         2000
> > +#define SSI_MAX_CLK_DIVIDER    254
> > +#define SSI_MIN_CLK_DIVIDER    4
> > +
> > +struct uniphier_spi_priv {
> > +       void __iomem *base;
> > +       struct clk *clk;
> > +       struct spi_master *master;
> > +       struct completion xfer_done;
> > +
> > +       int error;
> > +       unsigned int tx_bytes;
> > +       unsigned int rx_bytes;
> > +       const u8 *tx_buf;
> > +       u8 *rx_buf;
> > +
> > +       bool is_save_param;
> > +       u8 bits_per_word;
> > +       u16 mode;
> > +       u32 speed_hz;
> > +};
> > +
> > +#define SSI_CTL                        0x00
> > +#define   SSI_CTL_EN           BIT(0)
> > +
> > +#define SSI_CKS                        0x04
> > +#define   SSI_CKS_CKRAT_MASK   GENMASK(7, 0)
> > +#define   SSI_CKS_CKPHS                BIT(14)
> > +#define   SSI_CKS_CKINIT       BIT(13)
> > +#define   SSI_CKS_CKDLY                BIT(12)
> > +
> > +#define SSI_TXWDS              0x08
> > +#define   SSI_TXWDS_WDLEN_MASK GENMASK(13, 8)
> > +#define   SSI_TXWDS_TDTF_MASK  GENMASK(7, 6)
> > +#define   SSI_TXWDS_DTLEN_MASK GENMASK(5, 0)
> > +
> > +#define SSI_RXWDS              0x0c
> > +#define   SSI_RXWDS_DTLEN_MASK GENMASK(5, 0)
> > +
> > +#define SSI_FPS                        0x10
> > +#define   SSI_FPS_FSPOL                BIT(15)
> > +#define   SSI_FPS_FSTRT                BIT(14)
> > +
> > +#define SSI_SR                 0x14
> > +#define   SSI_SR_RNE           BIT(0)
> > +
> > +#define SSI_IE                 0x18
> > +#define   SSI_IE_RCIE          BIT(3)
> > +#define   SSI_IE_RORIE         BIT(0)
> > +
> > +#define SSI_IS                 0x1c
> > +#define   SSI_IS_RXRS          BIT(9)
> > +#define   SSI_IS_RCID          BIT(3)
> > +#define   SSI_IS_RORID         BIT(0)
> > +
> > +#define SSI_IC                 0x1c
> > +#define   SSI_IC_TCIC          BIT(4)
> > +#define   SSI_IC_RCIC          BIT(3)
> > +#define   SSI_IC_RORIC         BIT(0)
> > +
> > +#define SSI_FC                 0x20
> > +#define   SSI_FC_TXFFL         BIT(12)
> > +#define   SSI_FC_TXFTH_MASK    GENMASK(11, 8)
> > +#define   SSI_FC_RXFFL         BIT(4)
> > +#define   SSI_FC_RXFTH_MASK    GENMASK(3, 0)
> > +
> > +#define SSI_TXDR               0x24
> > +#define SSI_RXDR               0x24
> > +
> > +#define SSI_FIFO_DEPTH         8U
> > +
> > +static inline unsigned int bytes_per_word(unsigned int bits) {
> > +       return bits <= 8 ? 1 : (bits <= 16 ? 2 : 4); }
> > +
> > +static inline void uniphier_spi_irq_enable(struct spi_device *spi,
> > +u32 mask) {
> > +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> > +       u32 val;
> > +
> > +       val = readl(priv->base + SSI_IE);
> > +       val |= mask;
> > +       writel(val, priv->base + SSI_IE); }
> > +
> > +static inline void uniphier_spi_irq_disable(struct spi_device *spi,
> > +u32 mask) {
> > +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> > +       u32 val;
> > +
> > +       val = readl(priv->base + SSI_IE);
> > +       val &= ~mask;
> > +       writel(val, priv->base + SSI_IE); }
> > +
> > +static void uniphier_spi_set_mode(struct spi_device *spi) {
> > +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> > +       u32 val1, val2;
> > +
> > +       /*
> > +        * clock setting
> > +        * CKPHS    capture timing. 0:rising edge, 1:falling edge
> > +        * CKINIT   clock initial level. 0:low, 1:high
> > +        * CKDLY    clock delay. 0:no delay, 1:delay depending on FSTRT
> > +        *          (FSTRT=0: 1 clock, FSTRT=1: 0.5 clock)
> > +        *
> > +        * frame setting
> > +        * FSPOL    frame signal porarity. 0: low, 1: high
> > +        * FSTRT    start frame timing
> > +        *          0: rising edge of clock, 1: falling edge of clock
> > +        */
> > +       switch (spi->mode & (SPI_CPOL | SPI_CPHA)) {
> > +       case SPI_MODE_0:
> > +               /* CKPHS=1, CKINIT=0, CKDLY=1, FSTRT=0 */
> > +               val1 = SSI_CKS_CKPHS | SSI_CKS_CKDLY;
> > +               val2 = 0;
> > +               break;
> > +       case SPI_MODE_1:
> > +               /* CKPHS=0, CKINIT=0, CKDLY=0, FSTRT=1 */
> > +               val1 = 0;
> > +               val2 = SSI_FPS_FSTRT;
> > +               break;
> > +       case SPI_MODE_2:
> > +               /* CKPHS=0, CKINIT=1, CKDLY=1, FSTRT=1 */
> > +               val1 = SSI_CKS_CKINIT | SSI_CKS_CKDLY;
> > +               val2 = SSI_FPS_FSTRT;
> > +               break;
> > +       case SPI_MODE_3:
> > +               /* CKPHS=1, CKINIT=1, CKDLY=0, FSTRT=0 */
> > +               val1 = SSI_CKS_CKPHS | SSI_CKS_CKINIT;
> > +               val2 = 0;
> > +               break;
> > +       }
> > +
> > +       if (!(spi->mode & SPI_CS_HIGH))
> > +               val2 |= SSI_FPS_FSPOL;
> > +
> > +       writel(val1, priv->base + SSI_CKS);
> > +       writel(val2, priv->base + SSI_FPS);
> > +
> > +       val1 = 0;
> > +       if (spi->mode & SPI_LSB_FIRST)
> > +               val1 |= FIELD_PREP(SSI_TXWDS_TDTF_MASK, 1);
> > +       writel(val1, priv->base + SSI_TXWDS);
> > +       writel(val1, priv->base + SSI_RXWDS); }
> > +
> > +static void uniphier_spi_set_transfer_size(struct spi_device *spi,
> > +int size) {
> > +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> > +       u32 val;
> > +
> > +       val = readl(priv->base + SSI_TXWDS);
> > +       val &= ~(SSI_TXWDS_WDLEN_MASK | SSI_TXWDS_DTLEN_MASK);
> > +       val |= FIELD_PREP(SSI_TXWDS_WDLEN_MASK, size);
> > +       val |= FIELD_PREP(SSI_TXWDS_DTLEN_MASK, size);
> > +       writel(val, priv->base + SSI_TXWDS);
> > +
> > +       val = readl(priv->base + SSI_RXWDS);
> > +       val &= ~SSI_RXWDS_DTLEN_MASK;
> > +       val |= FIELD_PREP(SSI_RXWDS_DTLEN_MASK, size);
> > +       writel(val, priv->base + SSI_RXWDS); }
> > +
> > +static void uniphier_spi_set_baudrate(struct spi_device *spi,
> > +                                     unsigned int speed) {
> > +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> > +       u32 val, ckdiv;
> > +
> > +       /*
> > +        * the supported rates are even numbers from 4 to 254. (4,6,8...254)
> > +        * round up as we look for equal or less speed
> > +        */
> > +       ckdiv = DIV_ROUND_UP(clk_get_rate(priv->clk), speed);
> > +       ckdiv = round_up(ckdiv, 2);
> > +
> > +       val = readl(priv->base + SSI_CKS);
> > +       val &= ~SSI_CKS_CKRAT_MASK;
> > +       val |= ckdiv & SSI_CKS_CKRAT_MASK;
> > +       writel(val, priv->base + SSI_CKS); }
> > +
> > +static void uniphier_spi_setup_transfer(struct spi_device *spi,
> > +                                      struct spi_transfer *t) {
> > +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> > +       u32 val;
> > +
> > +       priv->error = 0;
> > +       priv->tx_buf = t->tx_buf;
> > +       priv->rx_buf = t->rx_buf;
> > +       priv->tx_bytes = priv->rx_bytes = t->len;
> > +
> > +       if (!priv->is_save_param || priv->mode != spi->mode) {
> > +               uniphier_spi_set_mode(spi);
> > +               priv->mode = spi->mode;
> > +       }
> > +
> > +       if (!priv->is_save_param || priv->bits_per_word != t->bits_per_word) {
> > +               uniphier_spi_set_transfer_size(spi, t->bits_per_word);
> > +               priv->bits_per_word = t->bits_per_word;
> > +       }
> > +
> > +       if (!priv->is_save_param || priv->speed_hz != t->speed_hz) {
> > +               uniphier_spi_set_baudrate(spi, t->speed_hz);
> > +               priv->speed_hz = t->speed_hz;
> > +       }
> > +
> > +       if (!priv->is_save_param)
> > +               priv->is_save_param = true;
> > +
> > +       /* reset FIFOs */
> > +       val = SSI_FC_TXFFL | SSI_FC_RXFFL;
> > +       writel(val, priv->base + SSI_FC); }
> > +
> > +static void uniphier_spi_send(struct uniphier_spi_priv *priv) {
> > +       int wsize;
> > +       u32 val = 0;
> > +
> > +       wsize = min(bytes_per_word(priv->bits_per_word), priv->tx_bytes);
> > +       priv->tx_bytes -= wsize;
> > +
> > +       if (priv->tx_buf) {
> > +               switch (wsize) {
> > +               case 1:
> > +                       val = *priv->tx_buf;
> > +                       break;
> > +               case 2:
> > +                       val = get_unaligned_le16(priv->tx_buf);
> > +                       break;
> > +               case 4:
> > +                       val = get_unaligned_le32(priv->tx_buf);
> > +                       break;
> > +               }
> > +
> > +               priv->tx_buf += wsize;
> > +       }
> > +
> > +       writel(val, priv->base + SSI_TXDR); }
> > +
> > +static void uniphier_spi_recv(struct uniphier_spi_priv *priv) {
> > +       int rsize;
> > +       u32 val;
> > +
> > +       rsize = min(bytes_per_word(priv->bits_per_word), priv->rx_bytes);
> > +       priv->rx_bytes -= rsize;
> > +
> > +       val = readl(priv->base + SSI_RXDR);
> > +
> > +       if (priv->rx_buf) {
> > +               switch (rsize) {
> > +               case 1:
> > +                       *priv->rx_buf = val;
> > +                       break;
> > +               case 2:
> > +                       put_unaligned_le16(val, priv->rx_buf);
> > +                       break;
> > +               case 4:
> > +                       put_unaligned_le32(val, priv->rx_buf);
> > +                       break;
> > +               }
> > +
> > +               priv->rx_buf += rsize;
> > +       }
> > +}
> > +
> > +static void uniphier_spi_fill_tx_fifo(struct uniphier_spi_priv *priv)
> > +{
> > +       unsigned int tx_count;
> > +       u32 val;
> > +
> > +       tx_count = DIV_ROUND_UP(priv->tx_bytes,
> > +                               bytes_per_word(priv->bits_per_word));
> > +       tx_count = min(tx_count, SSI_FIFO_DEPTH);
> > +
> > +       /* set fifo threshold */
> > +       val = readl(priv->base + SSI_FC);
> > +       val &= ~(SSI_FC_TXFTH_MASK | SSI_FC_RXFTH_MASK);
> > +       val |= FIELD_PREP(SSI_FC_TXFTH_MASK, tx_count);
> > +       val |= FIELD_PREP(SSI_FC_RXFTH_MASK, tx_count);
> > +       writel(val, priv->base + SSI_FC);
> > +
> > +       while (tx_count--)
> > +               uniphier_spi_send(priv); }
> > +
> > +static void uniphier_spi_set_cs(struct spi_device *spi, bool enable)
> > +{
> > +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> > +       u32 val;
> > +
> > +       val = readl(priv->base + SSI_FPS);
> > +
> > +       if (enable)
> > +               val |= SSI_FPS_FSPOL;
> > +       else
> > +               val &= ~SSI_FPS_FSPOL;
> > +
> > +       writel(val, priv->base + SSI_FPS); }
> > +
> > +static int uniphier_spi_transfer_one(struct spi_master *master,
> > +                                    struct spi_device *spi,
> > +                                    struct spi_transfer *t) {
> > +       struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
> > +       int status;
> > +
> > +       uniphier_spi_setup_transfer(spi, t);
> > +
> > +       reinit_completion(&priv->xfer_done);
> > +
> > +       uniphier_spi_fill_tx_fifo(priv);
> > +
> > +       uniphier_spi_irq_enable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
> > +
> > +       status = wait_for_completion_timeout(&priv->xfer_done,
> > +
> > + msecs_to_jiffies(SSI_TIMEOUT_MS));
> > +
> > +       uniphier_spi_irq_disable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
> > +
> > +       if (status < 0)
> > +               return status;
> > +
> > +       return priv->error;
> > +}
> > +
> > +static int uniphier_spi_prepare_transfer_hardware(struct spi_master
> > +*master) {
> > +       struct uniphier_spi_priv *priv =
> > +spi_master_get_devdata(master);
> > +
> > +       writel(SSI_CTL_EN, priv->base + SSI_CTL);
> > +
> > +       return 0;
> > +}
> > +
> > +static int uniphier_spi_unprepare_transfer_hardware(struct spi_master
> > +*master) {
> > +       struct uniphier_spi_priv *priv =
> > +spi_master_get_devdata(master);
> > +
> > +       writel(0, priv->base + SSI_CTL);
> > +
> > +       return 0;
> > +}
> > +
> > +static irqreturn_t uniphier_spi_handler(int irq, void *dev_id) {
> > +       struct uniphier_spi_priv *priv = dev_id;
> > +       u32 val, stat;
> > +
> > +       stat = readl(priv->base + SSI_IS);
> > +       val = SSI_IC_TCIC | SSI_IC_RCIC | SSI_IC_RORIC;
> > +       writel(val, priv->base + SSI_IC);
> > +
> > +       /* rx fifo overrun */
> > +       if (stat & SSI_IS_RORID) {
> > +               priv->error = -EIO;
> > +               goto done;
> > +       }
> > +
> > +       /* rx complete */
> > +       if ((stat & SSI_IS_RCID) && (stat & SSI_IS_RXRS)) {
> > +               while ((readl(priv->base + SSI_SR) & SSI_SR_RNE) &&
> > +                               (priv->rx_bytes - priv->tx_bytes) > 0)
> > +                       uniphier_spi_recv(priv);
> > +
> > +               if ((readl(priv->base + SSI_SR) & SSI_SR_RNE) ||
> > +                               (priv->rx_bytes != priv->tx_bytes)) {
> > +                       priv->error = -EIO;
> > +                       goto done;
> > +               } else if (priv->rx_bytes == 0)
> > +                       goto done;
> > +
> > +               /* next tx transfer */
> > +               uniphier_spi_fill_tx_fifo(priv);
> > +
> > +               return IRQ_HANDLED;
> > +       }
> > +
> > +       return IRQ_NONE;
> > +
> > +done:
> > +       complete(&priv->xfer_done);
> > +       return IRQ_HANDLED;
> > +}
> > +
> > +static int uniphier_spi_probe(struct platform_device *pdev) {
> > +       struct uniphier_spi_priv *priv;
> > +       struct spi_master *master;
> > +       struct resource *res;
> > +       unsigned long clk_rate;
> > +       int irq;
> > +       int ret;
> > +
> > +       master = spi_alloc_master(&pdev->dev, sizeof(*priv));
> > +       if (!master)
> > +               return -ENOMEM;
> > +
> > +       platform_set_drvdata(pdev, master);
> > +
> > +       priv = spi_master_get_devdata(master);
> > +       priv->master = master;
> > +       priv->is_save_param = false;
> > +
> > +       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +       priv->base = devm_ioremap_resource(&pdev->dev, res);
> > +       if (IS_ERR(priv->base)) {
> > +               ret = PTR_ERR(priv->base);
> > +               goto out_master_put;
> > +       }
> > +
> > +       priv->clk = devm_clk_get(&pdev->dev, NULL);
> > +       if (IS_ERR(priv->clk)) {
> > +               dev_err(&pdev->dev, "failed to get clock\n");
> > +               ret = PTR_ERR(priv->clk);
> > +               goto out_master_put;
> > +       }
> > +
> > +       ret = clk_prepare_enable(priv->clk);
> > +       if (ret)
> > +               goto out_master_put;
> > +
> > +       irq = platform_get_irq(pdev, 0);
> > +       if (irq < 0) {
> > +               dev_err(&pdev->dev, "failed to get IRQ\n");
> > +               ret = irq;
> > +               goto out_disable_clk;
> > +       }
> > +
> > +       ret = devm_request_irq(&pdev->dev, irq, uniphier_spi_handler,
> > +                              0, "uniphier-spi", priv);
> > +       if (ret) {
> > +               dev_err(&pdev->dev, "failed to request IRQ\n");
> > +               goto out_disable_clk;
> > +       }
> > +
> > +       init_completion(&priv->xfer_done);
> > +
> > +       clk_rate = clk_get_rate(priv->clk);
> > +
> > +       master->max_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MIN_CLK_DIVIDER);
> > +       master->min_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MAX_CLK_DIVIDER);
> > +       master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
> > +       master->dev.of_node = pdev->dev.of_node;
> > +       master->bus_num = pdev->id;
> > +       master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
> > +
> > +       master->set_cs = uniphier_spi_set_cs;
> > +       master->transfer_one = uniphier_spi_transfer_one;
> > +       master->prepare_transfer_hardware
> > +                               = uniphier_spi_prepare_transfer_hardware;
> > +       master->unprepare_transfer_hardware
> > +                               = uniphier_spi_unprepare_transfer_hardware;
> > +       master->num_chipselect = 1;
> > +
> > +       ret = devm_spi_register_master(&pdev->dev, master);
> > +       if (ret)
> > +               goto out_disable_clk;
> > +
> > +       return 0;
> > +
> > +out_disable_clk:
> > +       clk_disable_unprepare(priv->clk);
> > +
> > +out_master_put:
> > +       spi_master_put(master);
> > +       return ret;
> > +}
> > +
> > +static int uniphier_spi_remove(struct platform_device *pdev) {
> > +       struct uniphier_spi_priv *priv = platform_get_drvdata(pdev);
> > +
> > +       clk_disable_unprepare(priv->clk);
> > +
> > +       return 0;
> > +}
> > +
> > +static const struct of_device_id uniphier_spi_match[] = {
> > +       { .compatible = "socionext,uniphier-scssi" },
> > +       { /* sentinel */ }
> > +};
> > +MODULE_DEVICE_TABLE(of, uniphier_spi_match);
> > +
> > +static struct platform_driver uniphier_spi_driver = {
> > +       .probe = uniphier_spi_probe,
> > +       .remove = uniphier_spi_remove,
> > +       .driver = {
> > +               .name = "uniphier-spi",
> > +               .of_match_table = uniphier_spi_match,
> > +       },
> > +};
> > +module_platform_driver(uniphier_spi_driver);
> > +
> > +MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
> > +MODULE_AUTHOR("Keiji Hayashibara <hayashibara.keiji@socionext.com>");
> > +MODULE_DESCRIPTION("Socionext UniPhier SPI controller driver");
> > +MODULE_LICENSE("GPL v2");
> > --
> > 2.7.4
> >
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-spi"
> > in the body of a message to majordomo@vger.kernel.org More majordomo
> > info at  http://vger.kernel.org/majordomo-info.html
> 
> 
> 
> --
> With Best Regards,
> Andy Shevchenko

--
Best Regards,
Keiji Hayashibara



^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH v3 2/2] spi: add SPI controller driver for UniPhier SoC
@ 2018-08-02  7:52       ` Keiji Hayashibara
  0 siblings, 0 replies; 14+ messages in thread
From: Keiji Hayashibara @ 2018-08-02  7:52 UTC (permalink / raw)
  To: linux-arm-kernel

Hi Andy,

Thank you for your check.


> From: Andy Shevchenko [mailto:andy.shevchenko at gmail.com]
> Sent: Wednesday, August 1, 2018 7:21 PM
> To: Hayashibara, Keiji/?? ?? <hayashibara.keiji@socionext.com>
> Subject: Re: [PATCH v3 2/2] spi: add SPI controller driver for UniPhier SoC
> 
> On Wed, Aug 1, 2018 at 10:29 AM, Keiji Hayashibara <hayashibara.keiji@socionext.com> wrote:
> > Add SPI controller driver implemented in Socionext UniPhier SoCs.
> >
> > UniPhier SoCs have two types SPI controllers; SCSSI supports a single
> > channel, and MCSSI supports multiple channels.
> > This driver supports SCSSI only.
> >
> > This controller has 32bit TX/RX FIFO with depth of eight entry, and
> > supports the SPI master mode only.
> >
> > This commit is implemented in PIO transfer mode, not DMA transfer.
> >
> 
> One comment below, otherwise FWIW,
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> 
> 
> > Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
> > Signed-off-by: Keiji Hayashibara <hayashibara.keiji@socionext.com>
> > ---
> >  drivers/spi/Kconfig        |  13 ++
> >  drivers/spi/Makefile       |   1 +
> >  drivers/spi/spi-uniphier.c | 525
> > +++++++++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 539 insertions(+)
> >  create mode 100644 drivers/spi/spi-uniphier.c
> >
> > diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index
> > ad5d68e..671d078 100644
> > --- a/drivers/spi/Kconfig
> > +++ b/drivers/spi/Kconfig
> > @@ -688,6 +688,19 @@ config SPI_TXX9
> >         help
> >           SPI driver for Toshiba TXx9 MIPS SoCs
> >
> > +config SPI_UNIPHIER
> > +       tristate "Socionext UniPhier SPI Controller"
> > +       depends on (ARCH_UNIPHIER || COMPILE_TEST) && OF
> > +       help
> > +         This enables a driver for the Socionext UniPhier SoC SCSSI SPI controller.
> > +
> > +         UniPhier SoCs have SCSSI and MCSSI SPI controllers.
> > +         Every UniPhier SoC has SCSSI which supports single channel.
> > +         Older UniPhier Pro4/Pro5 also has MCSSI which support multiple channels.
> > +         This driver supports SCSSI only.
> > +
> > +         If your SoC supports SCSSI, say Y here.
> > +
> >  config SPI_XCOMM
> >         tristate "Analog Devices AD-FMCOMMS1-EBZ SPI-I2C-bridge driver"
> >         depends on I2C
> > diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index
> > cb1f437..a90d559 100644
> > --- a/drivers/spi/Makefile
> > +++ b/drivers/spi/Makefile
> > @@ -101,6 +101,7 @@ spi-thunderx-objs                   := spi-cavium.o spi-cavium-thunderx.o
> >  obj-$(CONFIG_SPI_THUNDERX)             += spi-thunderx.o
> >  obj-$(CONFIG_SPI_TOPCLIFF_PCH)         += spi-topcliff-pch.o
> >  obj-$(CONFIG_SPI_TXX9)                 += spi-txx9.o
> > +obj-$(CONFIG_SPI_UNIPHIER)             += spi-uniphier.o
> >  obj-$(CONFIG_SPI_XCOMM)                += spi-xcomm.o
> >  obj-$(CONFIG_SPI_XILINX)               += spi-xilinx.o
> >  obj-$(CONFIG_SPI_XLP)                  += spi-xlp.o
> > diff --git a/drivers/spi/spi-uniphier.c b/drivers/spi/spi-uniphier.c
> > new file mode 100644 index 0000000..0899854
> > --- /dev/null
> > +++ b/drivers/spi/spi-uniphier.c
> > @@ -0,0 +1,525 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +// spi-uniphier.c - Socionext UniPhier SPI controller driver
> > +// Copyright 2012      Panasonic Corporation
> > +// Copyright 2016-2018 Socionext Inc.
> > +
> > +#include <linux/kernel.h>
> > +#include <linux/bitfield.h>
> > +#include <linux/bitops.h>
> > +#include <linux/clk.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/io.h>
> > +#include <linux/module.h>
> 
> > +#include <linux/of.h>
> > +#include <linux/of_platform.h>
> 
> I fail to find where those two are used, just remove them.

I sent this modification as a new patch.
https://patchwork.kernel.org/patch/10553249/


> > +#include <linux/platform_device.h>
> > +#include <linux/spi/spi.h>
> > +
> > +#include <asm/unaligned.h>
> > +
> > +#define SSI_TIMEOUT_MS         2000
> > +#define SSI_MAX_CLK_DIVIDER    254
> > +#define SSI_MIN_CLK_DIVIDER    4
> > +
> > +struct uniphier_spi_priv {
> > +       void __iomem *base;
> > +       struct clk *clk;
> > +       struct spi_master *master;
> > +       struct completion xfer_done;
> > +
> > +       int error;
> > +       unsigned int tx_bytes;
> > +       unsigned int rx_bytes;
> > +       const u8 *tx_buf;
> > +       u8 *rx_buf;
> > +
> > +       bool is_save_param;
> > +       u8 bits_per_word;
> > +       u16 mode;
> > +       u32 speed_hz;
> > +};
> > +
> > +#define SSI_CTL                        0x00
> > +#define   SSI_CTL_EN           BIT(0)
> > +
> > +#define SSI_CKS                        0x04
> > +#define   SSI_CKS_CKRAT_MASK   GENMASK(7, 0)
> > +#define   SSI_CKS_CKPHS                BIT(14)
> > +#define   SSI_CKS_CKINIT       BIT(13)
> > +#define   SSI_CKS_CKDLY                BIT(12)
> > +
> > +#define SSI_TXWDS              0x08
> > +#define   SSI_TXWDS_WDLEN_MASK GENMASK(13, 8)
> > +#define   SSI_TXWDS_TDTF_MASK  GENMASK(7, 6)
> > +#define   SSI_TXWDS_DTLEN_MASK GENMASK(5, 0)
> > +
> > +#define SSI_RXWDS              0x0c
> > +#define   SSI_RXWDS_DTLEN_MASK GENMASK(5, 0)
> > +
> > +#define SSI_FPS                        0x10
> > +#define   SSI_FPS_FSPOL                BIT(15)
> > +#define   SSI_FPS_FSTRT                BIT(14)
> > +
> > +#define SSI_SR                 0x14
> > +#define   SSI_SR_RNE           BIT(0)
> > +
> > +#define SSI_IE                 0x18
> > +#define   SSI_IE_RCIE          BIT(3)
> > +#define   SSI_IE_RORIE         BIT(0)
> > +
> > +#define SSI_IS                 0x1c
> > +#define   SSI_IS_RXRS          BIT(9)
> > +#define   SSI_IS_RCID          BIT(3)
> > +#define   SSI_IS_RORID         BIT(0)
> > +
> > +#define SSI_IC                 0x1c
> > +#define   SSI_IC_TCIC          BIT(4)
> > +#define   SSI_IC_RCIC          BIT(3)
> > +#define   SSI_IC_RORIC         BIT(0)
> > +
> > +#define SSI_FC                 0x20
> > +#define   SSI_FC_TXFFL         BIT(12)
> > +#define   SSI_FC_TXFTH_MASK    GENMASK(11, 8)
> > +#define   SSI_FC_RXFFL         BIT(4)
> > +#define   SSI_FC_RXFTH_MASK    GENMASK(3, 0)
> > +
> > +#define SSI_TXDR               0x24
> > +#define SSI_RXDR               0x24
> > +
> > +#define SSI_FIFO_DEPTH         8U
> > +
> > +static inline unsigned int bytes_per_word(unsigned int bits) {
> > +       return bits <= 8 ? 1 : (bits <= 16 ? 2 : 4); }
> > +
> > +static inline void uniphier_spi_irq_enable(struct spi_device *spi,
> > +u32 mask) {
> > +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> > +       u32 val;
> > +
> > +       val = readl(priv->base + SSI_IE);
> > +       val |= mask;
> > +       writel(val, priv->base + SSI_IE); }
> > +
> > +static inline void uniphier_spi_irq_disable(struct spi_device *spi,
> > +u32 mask) {
> > +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> > +       u32 val;
> > +
> > +       val = readl(priv->base + SSI_IE);
> > +       val &= ~mask;
> > +       writel(val, priv->base + SSI_IE); }
> > +
> > +static void uniphier_spi_set_mode(struct spi_device *spi) {
> > +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> > +       u32 val1, val2;
> > +
> > +       /*
> > +        * clock setting
> > +        * CKPHS    capture timing. 0:rising edge, 1:falling edge
> > +        * CKINIT   clock initial level. 0:low, 1:high
> > +        * CKDLY    clock delay. 0:no delay, 1:delay depending on FSTRT
> > +        *          (FSTRT=0: 1 clock, FSTRT=1: 0.5 clock)
> > +        *
> > +        * frame setting
> > +        * FSPOL    frame signal porarity. 0: low, 1: high
> > +        * FSTRT    start frame timing
> > +        *          0: rising edge of clock, 1: falling edge of clock
> > +        */
> > +       switch (spi->mode & (SPI_CPOL | SPI_CPHA)) {
> > +       case SPI_MODE_0:
> > +               /* CKPHS=1, CKINIT=0, CKDLY=1, FSTRT=0 */
> > +               val1 = SSI_CKS_CKPHS | SSI_CKS_CKDLY;
> > +               val2 = 0;
> > +               break;
> > +       case SPI_MODE_1:
> > +               /* CKPHS=0, CKINIT=0, CKDLY=0, FSTRT=1 */
> > +               val1 = 0;
> > +               val2 = SSI_FPS_FSTRT;
> > +               break;
> > +       case SPI_MODE_2:
> > +               /* CKPHS=0, CKINIT=1, CKDLY=1, FSTRT=1 */
> > +               val1 = SSI_CKS_CKINIT | SSI_CKS_CKDLY;
> > +               val2 = SSI_FPS_FSTRT;
> > +               break;
> > +       case SPI_MODE_3:
> > +               /* CKPHS=1, CKINIT=1, CKDLY=0, FSTRT=0 */
> > +               val1 = SSI_CKS_CKPHS | SSI_CKS_CKINIT;
> > +               val2 = 0;
> > +               break;
> > +       }
> > +
> > +       if (!(spi->mode & SPI_CS_HIGH))
> > +               val2 |= SSI_FPS_FSPOL;
> > +
> > +       writel(val1, priv->base + SSI_CKS);
> > +       writel(val2, priv->base + SSI_FPS);
> > +
> > +       val1 = 0;
> > +       if (spi->mode & SPI_LSB_FIRST)
> > +               val1 |= FIELD_PREP(SSI_TXWDS_TDTF_MASK, 1);
> > +       writel(val1, priv->base + SSI_TXWDS);
> > +       writel(val1, priv->base + SSI_RXWDS); }
> > +
> > +static void uniphier_spi_set_transfer_size(struct spi_device *spi,
> > +int size) {
> > +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> > +       u32 val;
> > +
> > +       val = readl(priv->base + SSI_TXWDS);
> > +       val &= ~(SSI_TXWDS_WDLEN_MASK | SSI_TXWDS_DTLEN_MASK);
> > +       val |= FIELD_PREP(SSI_TXWDS_WDLEN_MASK, size);
> > +       val |= FIELD_PREP(SSI_TXWDS_DTLEN_MASK, size);
> > +       writel(val, priv->base + SSI_TXWDS);
> > +
> > +       val = readl(priv->base + SSI_RXWDS);
> > +       val &= ~SSI_RXWDS_DTLEN_MASK;
> > +       val |= FIELD_PREP(SSI_RXWDS_DTLEN_MASK, size);
> > +       writel(val, priv->base + SSI_RXWDS); }
> > +
> > +static void uniphier_spi_set_baudrate(struct spi_device *spi,
> > +                                     unsigned int speed) {
> > +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> > +       u32 val, ckdiv;
> > +
> > +       /*
> > +        * the supported rates are even numbers from 4 to 254. (4,6,8...254)
> > +        * round up as we look for equal or less speed
> > +        */
> > +       ckdiv = DIV_ROUND_UP(clk_get_rate(priv->clk), speed);
> > +       ckdiv = round_up(ckdiv, 2);
> > +
> > +       val = readl(priv->base + SSI_CKS);
> > +       val &= ~SSI_CKS_CKRAT_MASK;
> > +       val |= ckdiv & SSI_CKS_CKRAT_MASK;
> > +       writel(val, priv->base + SSI_CKS); }
> > +
> > +static void uniphier_spi_setup_transfer(struct spi_device *spi,
> > +                                      struct spi_transfer *t) {
> > +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> > +       u32 val;
> > +
> > +       priv->error = 0;
> > +       priv->tx_buf = t->tx_buf;
> > +       priv->rx_buf = t->rx_buf;
> > +       priv->tx_bytes = priv->rx_bytes = t->len;
> > +
> > +       if (!priv->is_save_param || priv->mode != spi->mode) {
> > +               uniphier_spi_set_mode(spi);
> > +               priv->mode = spi->mode;
> > +       }
> > +
> > +       if (!priv->is_save_param || priv->bits_per_word != t->bits_per_word) {
> > +               uniphier_spi_set_transfer_size(spi, t->bits_per_word);
> > +               priv->bits_per_word = t->bits_per_word;
> > +       }
> > +
> > +       if (!priv->is_save_param || priv->speed_hz != t->speed_hz) {
> > +               uniphier_spi_set_baudrate(spi, t->speed_hz);
> > +               priv->speed_hz = t->speed_hz;
> > +       }
> > +
> > +       if (!priv->is_save_param)
> > +               priv->is_save_param = true;
> > +
> > +       /* reset FIFOs */
> > +       val = SSI_FC_TXFFL | SSI_FC_RXFFL;
> > +       writel(val, priv->base + SSI_FC); }
> > +
> > +static void uniphier_spi_send(struct uniphier_spi_priv *priv) {
> > +       int wsize;
> > +       u32 val = 0;
> > +
> > +       wsize = min(bytes_per_word(priv->bits_per_word), priv->tx_bytes);
> > +       priv->tx_bytes -= wsize;
> > +
> > +       if (priv->tx_buf) {
> > +               switch (wsize) {
> > +               case 1:
> > +                       val = *priv->tx_buf;
> > +                       break;
> > +               case 2:
> > +                       val = get_unaligned_le16(priv->tx_buf);
> > +                       break;
> > +               case 4:
> > +                       val = get_unaligned_le32(priv->tx_buf);
> > +                       break;
> > +               }
> > +
> > +               priv->tx_buf += wsize;
> > +       }
> > +
> > +       writel(val, priv->base + SSI_TXDR); }
> > +
> > +static void uniphier_spi_recv(struct uniphier_spi_priv *priv) {
> > +       int rsize;
> > +       u32 val;
> > +
> > +       rsize = min(bytes_per_word(priv->bits_per_word), priv->rx_bytes);
> > +       priv->rx_bytes -= rsize;
> > +
> > +       val = readl(priv->base + SSI_RXDR);
> > +
> > +       if (priv->rx_buf) {
> > +               switch (rsize) {
> > +               case 1:
> > +                       *priv->rx_buf = val;
> > +                       break;
> > +               case 2:
> > +                       put_unaligned_le16(val, priv->rx_buf);
> > +                       break;
> > +               case 4:
> > +                       put_unaligned_le32(val, priv->rx_buf);
> > +                       break;
> > +               }
> > +
> > +               priv->rx_buf += rsize;
> > +       }
> > +}
> > +
> > +static void uniphier_spi_fill_tx_fifo(struct uniphier_spi_priv *priv)
> > +{
> > +       unsigned int tx_count;
> > +       u32 val;
> > +
> > +       tx_count = DIV_ROUND_UP(priv->tx_bytes,
> > +                               bytes_per_word(priv->bits_per_word));
> > +       tx_count = min(tx_count, SSI_FIFO_DEPTH);
> > +
> > +       /* set fifo threshold */
> > +       val = readl(priv->base + SSI_FC);
> > +       val &= ~(SSI_FC_TXFTH_MASK | SSI_FC_RXFTH_MASK);
> > +       val |= FIELD_PREP(SSI_FC_TXFTH_MASK, tx_count);
> > +       val |= FIELD_PREP(SSI_FC_RXFTH_MASK, tx_count);
> > +       writel(val, priv->base + SSI_FC);
> > +
> > +       while (tx_count--)
> > +               uniphier_spi_send(priv); }
> > +
> > +static void uniphier_spi_set_cs(struct spi_device *spi, bool enable)
> > +{
> > +       struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
> > +       u32 val;
> > +
> > +       val = readl(priv->base + SSI_FPS);
> > +
> > +       if (enable)
> > +               val |= SSI_FPS_FSPOL;
> > +       else
> > +               val &= ~SSI_FPS_FSPOL;
> > +
> > +       writel(val, priv->base + SSI_FPS); }
> > +
> > +static int uniphier_spi_transfer_one(struct spi_master *master,
> > +                                    struct spi_device *spi,
> > +                                    struct spi_transfer *t) {
> > +       struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
> > +       int status;
> > +
> > +       uniphier_spi_setup_transfer(spi, t);
> > +
> > +       reinit_completion(&priv->xfer_done);
> > +
> > +       uniphier_spi_fill_tx_fifo(priv);
> > +
> > +       uniphier_spi_irq_enable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
> > +
> > +       status = wait_for_completion_timeout(&priv->xfer_done,
> > +
> > + msecs_to_jiffies(SSI_TIMEOUT_MS));
> > +
> > +       uniphier_spi_irq_disable(spi, SSI_IE_RCIE | SSI_IE_RORIE);
> > +
> > +       if (status < 0)
> > +               return status;
> > +
> > +       return priv->error;
> > +}
> > +
> > +static int uniphier_spi_prepare_transfer_hardware(struct spi_master
> > +*master) {
> > +       struct uniphier_spi_priv *priv =
> > +spi_master_get_devdata(master);
> > +
> > +       writel(SSI_CTL_EN, priv->base + SSI_CTL);
> > +
> > +       return 0;
> > +}
> > +
> > +static int uniphier_spi_unprepare_transfer_hardware(struct spi_master
> > +*master) {
> > +       struct uniphier_spi_priv *priv =
> > +spi_master_get_devdata(master);
> > +
> > +       writel(0, priv->base + SSI_CTL);
> > +
> > +       return 0;
> > +}
> > +
> > +static irqreturn_t uniphier_spi_handler(int irq, void *dev_id) {
> > +       struct uniphier_spi_priv *priv = dev_id;
> > +       u32 val, stat;
> > +
> > +       stat = readl(priv->base + SSI_IS);
> > +       val = SSI_IC_TCIC | SSI_IC_RCIC | SSI_IC_RORIC;
> > +       writel(val, priv->base + SSI_IC);
> > +
> > +       /* rx fifo overrun */
> > +       if (stat & SSI_IS_RORID) {
> > +               priv->error = -EIO;
> > +               goto done;
> > +       }
> > +
> > +       /* rx complete */
> > +       if ((stat & SSI_IS_RCID) && (stat & SSI_IS_RXRS)) {
> > +               while ((readl(priv->base + SSI_SR) & SSI_SR_RNE) &&
> > +                               (priv->rx_bytes - priv->tx_bytes) > 0)
> > +                       uniphier_spi_recv(priv);
> > +
> > +               if ((readl(priv->base + SSI_SR) & SSI_SR_RNE) ||
> > +                               (priv->rx_bytes != priv->tx_bytes)) {
> > +                       priv->error = -EIO;
> > +                       goto done;
> > +               } else if (priv->rx_bytes == 0)
> > +                       goto done;
> > +
> > +               /* next tx transfer */
> > +               uniphier_spi_fill_tx_fifo(priv);
> > +
> > +               return IRQ_HANDLED;
> > +       }
> > +
> > +       return IRQ_NONE;
> > +
> > +done:
> > +       complete(&priv->xfer_done);
> > +       return IRQ_HANDLED;
> > +}
> > +
> > +static int uniphier_spi_probe(struct platform_device *pdev) {
> > +       struct uniphier_spi_priv *priv;
> > +       struct spi_master *master;
> > +       struct resource *res;
> > +       unsigned long clk_rate;
> > +       int irq;
> > +       int ret;
> > +
> > +       master = spi_alloc_master(&pdev->dev, sizeof(*priv));
> > +       if (!master)
> > +               return -ENOMEM;
> > +
> > +       platform_set_drvdata(pdev, master);
> > +
> > +       priv = spi_master_get_devdata(master);
> > +       priv->master = master;
> > +       priv->is_save_param = false;
> > +
> > +       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +       priv->base = devm_ioremap_resource(&pdev->dev, res);
> > +       if (IS_ERR(priv->base)) {
> > +               ret = PTR_ERR(priv->base);
> > +               goto out_master_put;
> > +       }
> > +
> > +       priv->clk = devm_clk_get(&pdev->dev, NULL);
> > +       if (IS_ERR(priv->clk)) {
> > +               dev_err(&pdev->dev, "failed to get clock\n");
> > +               ret = PTR_ERR(priv->clk);
> > +               goto out_master_put;
> > +       }
> > +
> > +       ret = clk_prepare_enable(priv->clk);
> > +       if (ret)
> > +               goto out_master_put;
> > +
> > +       irq = platform_get_irq(pdev, 0);
> > +       if (irq < 0) {
> > +               dev_err(&pdev->dev, "failed to get IRQ\n");
> > +               ret = irq;
> > +               goto out_disable_clk;
> > +       }
> > +
> > +       ret = devm_request_irq(&pdev->dev, irq, uniphier_spi_handler,
> > +                              0, "uniphier-spi", priv);
> > +       if (ret) {
> > +               dev_err(&pdev->dev, "failed to request IRQ\n");
> > +               goto out_disable_clk;
> > +       }
> > +
> > +       init_completion(&priv->xfer_done);
> > +
> > +       clk_rate = clk_get_rate(priv->clk);
> > +
> > +       master->max_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MIN_CLK_DIVIDER);
> > +       master->min_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MAX_CLK_DIVIDER);
> > +       master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
> > +       master->dev.of_node = pdev->dev.of_node;
> > +       master->bus_num = pdev->id;
> > +       master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
> > +
> > +       master->set_cs = uniphier_spi_set_cs;
> > +       master->transfer_one = uniphier_spi_transfer_one;
> > +       master->prepare_transfer_hardware
> > +                               = uniphier_spi_prepare_transfer_hardware;
> > +       master->unprepare_transfer_hardware
> > +                               = uniphier_spi_unprepare_transfer_hardware;
> > +       master->num_chipselect = 1;
> > +
> > +       ret = devm_spi_register_master(&pdev->dev, master);
> > +       if (ret)
> > +               goto out_disable_clk;
> > +
> > +       return 0;
> > +
> > +out_disable_clk:
> > +       clk_disable_unprepare(priv->clk);
> > +
> > +out_master_put:
> > +       spi_master_put(master);
> > +       return ret;
> > +}
> > +
> > +static int uniphier_spi_remove(struct platform_device *pdev) {
> > +       struct uniphier_spi_priv *priv = platform_get_drvdata(pdev);
> > +
> > +       clk_disable_unprepare(priv->clk);
> > +
> > +       return 0;
> > +}
> > +
> > +static const struct of_device_id uniphier_spi_match[] = {
> > +       { .compatible = "socionext,uniphier-scssi" },
> > +       { /* sentinel */ }
> > +};
> > +MODULE_DEVICE_TABLE(of, uniphier_spi_match);
> > +
> > +static struct platform_driver uniphier_spi_driver = {
> > +       .probe = uniphier_spi_probe,
> > +       .remove = uniphier_spi_remove,
> > +       .driver = {
> > +               .name = "uniphier-spi",
> > +               .of_match_table = uniphier_spi_match,
> > +       },
> > +};
> > +module_platform_driver(uniphier_spi_driver);
> > +
> > +MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
> > +MODULE_AUTHOR("Keiji Hayashibara <hayashibara.keiji@socionext.com>");
> > +MODULE_DESCRIPTION("Socionext UniPhier SPI controller driver");
> > +MODULE_LICENSE("GPL v2");
> > --
> > 2.7.4
> >
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-spi"
> > in the body of a message to majordomo at vger.kernel.org More majordomo
> > info at  http://vger.kernel.org/majordomo-info.html
> 
> 
> 
> --
> With Best Regards,
> Andy Shevchenko

--
Best Regards,
Keiji Hayashibara

^ permalink raw reply	[flat|nested] 14+ messages in thread

end of thread, other threads:[~2018-08-02  7:52 UTC | newest]

Thread overview: 14+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-08-01  7:29 [PATCH v3 0/2] add SPI controller driver for UniPhier SoCs Keiji Hayashibara
2018-08-01  7:29 ` Keiji Hayashibara
2018-08-01  7:29 ` [PATCH v3 1/2] dt-bindings: spi: add DT bindings for UniPhier SPI controller Keiji Hayashibara
2018-08-01  7:29   ` Keiji Hayashibara
2018-08-01  7:29 ` [PATCH v3 2/2] spi: add SPI controller driver for UniPhier SoC Keiji Hayashibara
2018-08-01  7:29   ` Keiji Hayashibara
2018-08-01 10:20   ` Andy Shevchenko
2018-08-01 10:20     ` Andy Shevchenko
2018-08-02  7:52     ` Keiji Hayashibara
2018-08-02  7:52       ` Keiji Hayashibara
2018-08-01 11:20   ` Applied "spi: add SPI controller driver for UniPhier SoC" to the spi tree Mark Brown
2018-08-01 11:20     ` Mark Brown
2018-08-01 11:20     ` Mark Brown
2018-08-01 11:20     ` Mark Brown

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