[PATCH v7 0/2] spi: driver for Cirrus EP93xx SPI controller

[PATCH v7 0/2] spi: driver for Cirrus EP93xx SPI controller

[Mika Westerberg]

Hello,

This series implements SPI master driver for Cirrus Logic EP93xx SPI
controllers.

Changes to previous (v6) version:
	- only cosmetic non-functional changes (removed unnecessary comments and
	  few inlines) based on review comments by H Hartley Sweeten

Tested on TS-7260 (ep9302) and Sim.One (ep9307) boards with mmc_spi and at25
drivers.

Note that patch 2/2 depends on patch that is already in Russell's patch
tracking system (and in linux-next)
	http://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=5998/1
So 2/2 should probably go in via Russell's tree.

Regards,
MW

Mika Westerberg (2):
  spi: implemented driver for Cirrus EP93xx SPI controller
  ep93xx: SPI driver platform support code

 Documentation/spi/ep93xx_spi                    |   95 +++
 arch/arm/mach-ep93xx/clock.c                    |   13 +
 arch/arm/mach-ep93xx/core.c                     |   52 ++
 arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h |    1 +
 arch/arm/mach-ep93xx/include/mach/ep93xx_spi.h  |   27 +
 arch/arm/mach-ep93xx/include/mach/platform.h    |    4 +
 drivers/spi/Kconfig                             |   10 +
 drivers/spi/Makefile                            |    1 +
 drivers/spi/ep93xx_spi.c                        |  938 +++++++++++++++++++++++
 9 files changed, 1141 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/spi/ep93xx_spi
 create mode 100644 arch/arm/mach-ep93xx/include/mach/ep93xx_spi.h
 create mode 100644 drivers/spi/ep93xx_spi.c


------------------------------------------------------------------------------

[PATCH v7 0/2] spi: driver for Cirrus EP93xx SPI controller

[Mika Westerberg]

Hello,

This series implements SPI master driver for Cirrus Logic EP93xx SPI
controllers.

Changes to previous (v6) version:
	- only cosmetic non-functional changes (removed unnecessary comments and
	  few inlines) based on review comments by H Hartley Sweeten

Tested on TS-7260 (ep9302) and Sim.One (ep9307) boards with mmc_spi and at25
drivers.

Note that patch 2/2 depends on patch that is already in Russell's patch
tracking system (and in linux-next)
	http://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=5998/1
So 2/2 should probably go in via Russell's tree.

Regards,
MW

Mika Westerberg (2):
  spi: implemented driver for Cirrus EP93xx SPI controller
  ep93xx: SPI driver platform support code

 Documentation/spi/ep93xx_spi                    |   95 +++
 arch/arm/mach-ep93xx/clock.c                    |   13 +
 arch/arm/mach-ep93xx/core.c                     |   52 ++
 arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h |    1 +
 arch/arm/mach-ep93xx/include/mach/ep93xx_spi.h  |   27 +
 arch/arm/mach-ep93xx/include/mach/platform.h    |    4 +
 drivers/spi/Kconfig                             |   10 +
 drivers/spi/Makefile                            |    1 +
 drivers/spi/ep93xx_spi.c                        |  938 +++++++++++++++++++++++
 9 files changed, 1141 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/spi/ep93xx_spi
 create mode 100644 arch/arm/mach-ep93xx/include/mach/ep93xx_spi.h
 create mode 100644 drivers/spi/ep93xx_spi.c

[PATCH v7 1/2] spi: implemented driver for Cirrus EP93xx SPI controller

[Mika Westerberg]

This patch adds an SPI master driver for the Cirrus EP93xx SPI controller found
in EP93xx chips.

Signed-off-by: Mika Westerberg <mika.westerberg-X3B1VOXEql0@public.gmane.org>
Signed-off-by: H Hartley Sweeten <hsweeten-3FF4nKcrg1dE2c76skzGb0EOCMrvLtNR@public.gmane.org>
Acked-by: H Hartley Sweeten <hsweeten-3FF4nKcrg1dE2c76skzGb0EOCMrvLtNR@public.gmane.org>
Cc: Ryan Mallon <ryan-7Wk5F4Od5/oYd5yxfr4S2w@public.gmane.org>
Cc: David Brownell <dbrownell-Rn4VEauK+AKRv+LV9MX5uipxlwaOVQ5f@public.gmane.org>
Cc: Grant Likely <grant.likely-s3s/WqlpOiPyB63q8FvJNQ@public.gmane.org>
Cc: Martin Guy <martinwguy-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
 Documentation/spi/ep93xx_spi                   |   95 +++
 arch/arm/mach-ep93xx/include/mach/ep93xx_spi.h |   27 +
 drivers/spi/Kconfig                            |   10 +
 drivers/spi/Makefile                           |    1 +
 drivers/spi/ep93xx_spi.c                       |  938 ++++++++++++++++++++++++
 5 files changed, 1071 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/spi/ep93xx_spi
 create mode 100644 arch/arm/mach-ep93xx/include/mach/ep93xx_spi.h
 create mode 100644 drivers/spi/ep93xx_spi.c

diff --git a/Documentation/spi/ep93xx_spi b/Documentation/spi/ep93xx_spi
new file mode 100644
index 0000000..6325f5b
--- /dev/null
+++ b/Documentation/spi/ep93xx_spi
@@ -0,0 +1,95 @@
+Cirrus EP93xx SPI controller driver HOWTO
+=========================================
+
+ep93xx_spi driver brings SPI master support for EP93xx SPI controller.  Chip
+selects are implemented with GPIO lines.
+
+NOTE: If possible, don't use SFRMOUT (SFRM1) signal as a chip select. It will
+not work correctly (it cannot be controlled by software). Use GPIO lines
+instead.
+
+Sample configuration
+====================
+
+Typically driver configuration is done in platform board files (the files under
+arch/arm/mach-ep93xx/*.c). In this example we configure MMC over SPI through
+this driver on TS-7260 board. You can adapt the code to suit your needs.
+
+This example uses EGPIO9 as SD/MMC card chip select (this is wired in DIO1
+header on the board).
+
+You need to select CONFIG_MMC_SPI to use mmc_spi driver.
+
+arch/arm/mach-ep93xx/ts72xx.c:
+
+...
+#include <linux/gpio.h>
+#include <linux/spi/spi.h>
+
+#include <mach/ep93xx_spi.h>
+
+/* this is our GPIO line used for chip select */
+#define MMC_CHIP_SELECT_GPIO EP93XX_GPIO_LINE_EGPIO9
+
+static int ts72xx_mmc_spi_setup(struct spi_device *spi)
+{
+	int err;
+
+	err = gpio_request(MMC_CHIP_SELECT_GPIO, spi->modalias);
+	if (err)
+		return err;
+
+	gpio_direction_output(MMC_CHIP_SELECT_GPIO, 1);
+
+	return 0;
+}
+
+static void ts72xx_mmc_spi_cleanup(struct spi_device *spi)
+{
+	gpio_set_value(MMC_CHIP_SELECT_GPIO, 1);
+	gpio_direction_input(MMC_CHIP_SELECT_GPIO);
+	gpio_free(MMC_CHIP_SELECT_GPIO);
+}
+
+static void ts72xx_mmc_spi_cs_control(struct spi_device *spi, int value)
+{
+	gpio_set_value(MMC_CHIP_SELECT_GPIO, value);
+}
+
+static struct ep93xx_spi_chip_ops ts72xx_mmc_spi_ops = {
+	.setup		= ts72xx_mmc_spi_setup,
+	.cleanup	= ts72xx_mmc_spi_cleanup,
+	.cs_control	= ts72xx_mmc_spi_cs_control,
+};
+
+static struct spi_board_info ts72xx_spi_devices[] __initdata = {
+	{
+		.modalias		= "mmc_spi",
+		.controller_data	= &ts72xx_mmc_spi_ops,
+		/*
+		 * We use 10 MHz even though the maximum is 7.4 MHz. The driver
+		 * will limit it automatically to max. frequency.
+		 */
+		.max_speed_hz		= 10 * 1000 * 1000,
+		.bus_num		= 0,
+		.chip_select		= 0,
+		.mode			= SPI_MODE_0,
+	},
+};
+
+static struct ep93xx_spi_info ts72xx_spi_info = {
+	.num_chipselect	= ARRAY_SIZE(ts72xx_spi_devices),
+};
+
+static void __init ts72xx_init_machine(void)
+{
+	...
+	ep93xx_register_spi(&ts72xx_spi_info, ts72xx_spi_devices,
+			    ARRAY_SIZE(ts72xx_spi_devices));
+}
+
+Thanks to
+=========
+Martin Guy, H. Hartley Sweeten and others who helped me during development of
+the driver. Simplemachines.it donated me a Sim.One board which I used testing
+the driver on EP9307.
diff --git a/arch/arm/mach-ep93xx/include/mach/ep93xx_spi.h b/arch/arm/mach-ep93xx/include/mach/ep93xx_spi.h
new file mode 100644
index 0000000..0a37961
--- /dev/null
+++ b/arch/arm/mach-ep93xx/include/mach/ep93xx_spi.h
@@ -0,0 +1,27 @@
+#ifndef __ASM_MACH_EP93XX_SPI_H
+#define __ASM_MACH_EP93XX_SPI_H
+
+struct spi_device;
+
+/**
+ * struct ep93xx_spi_info - EP93xx specific SPI descriptor
+ * @num_chipselect: number of chip selects on this board, must be
+ *                  at least one
+ */
+struct ep93xx_spi_info {
+	int	num_chipselect;
+};
+
+/**
+ * struct ep93xx_spi_chip_ops - operation callbacks for SPI slave device
+ * @setup: setup the chip select mechanism
+ * @cleanup: cleanup the chip select mechanism
+ * @cs_control: control the device chip select
+ */
+struct ep93xx_spi_chip_ops {
+	int	(*setup)(struct spi_device *spi);
+	void	(*cleanup)(struct spi_device *spi);
+	void	(*cs_control)(struct spi_device *spi, int value);
+};
+
+#endif /* __ASM_MACH_EP93XX_SPI_H */
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index a191fa2..2b2f4c3 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -117,6 +117,16 @@ config SPI_DAVINCI
 	help
 	  SPI master controller for DaVinci and DA8xx SPI modules.
 
+config SPI_EP93XX
+	tristate "Cirrus Logic EP93xx SPI controller"
+	depends on ARCH_EP93XX
+	help
+	  This enables using the Cirrus EP93xx SPI controller in master
+	  mode.
+
+	  To compile this driver as a module, choose M here. The module will be
+	  called ep93xx_spi.
+
 config SPI_GPIO
 	tristate "GPIO-based bitbanging SPI Master"
 	depends on GENERIC_GPIO
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index d7d0f89..377f845 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -21,6 +21,7 @@ obj-$(CONFIG_SPI_DAVINCI)		+= davinci_spi.o
 obj-$(CONFIG_SPI_DESIGNWARE)		+= dw_spi.o
 obj-$(CONFIG_SPI_DW_PCI)		+= dw_spi_pci.o
 obj-$(CONFIG_SPI_DW_MMIO)		+= dw_spi_mmio.o
+obj-$(CONFIG_SPI_EP93XX)		+= ep93xx_spi.o
 obj-$(CONFIG_SPI_GPIO)			+= spi_gpio.o
 obj-$(CONFIG_SPI_IMX)			+= spi_imx.o
 obj-$(CONFIG_SPI_LM70_LLP)		+= spi_lm70llp.o
diff --git a/drivers/spi/ep93xx_spi.c b/drivers/spi/ep93xx_spi.c
new file mode 100644
index 0000000..0ba35df
--- /dev/null
+++ b/drivers/spi/ep93xx_spi.c
@@ -0,0 +1,938 @@
+/*
+ * Driver for Cirrus Logic EP93xx SPI controller.
+ *
+ * Copyright (c) 2010 Mika Westerberg
+ *
+ * Explicit FIFO handling code was inspired by amba-pl022 driver.
+ *
+ * Chip select support using other than built-in GPIOs by H. Hartley Sweeten.
+ *
+ * For more information about the SPI controller see documentation on Cirrus
+ * Logic web site:
+ *     http://www.cirrus.com/en/pubs/manual/EP93xx_Users_Guide_UM1.pdf
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/bitops.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/workqueue.h>
+#include <linux/sched.h>
+#include <linux/spi/spi.h>
+
+#include <mach/ep93xx_spi.h>
+
+#define SSPCR0			0x0000
+#define SSPCR0_MODE_SHIFT	6
+#define SSPCR0_SCR_SHIFT	8
+
+#define SSPCR1			0x0004
+#define SSPCR1_RIE		BIT(0)
+#define SSPCR1_TIE		BIT(1)
+#define SSPCR1_RORIE		BIT(2)
+#define SSPCR1_LBM		BIT(3)
+#define SSPCR1_SSE		BIT(4)
+#define SSPCR1_MS		BIT(5)
+#define SSPCR1_SOD		BIT(6)
+
+#define SSPDR			0x0008
+
+#define SSPSR			0x000c
+#define SSPSR_TFE		BIT(0)
+#define SSPSR_TNF		BIT(1)
+#define SSPSR_RNE		BIT(2)
+#define SSPSR_RFF		BIT(3)
+#define SSPSR_BSY		BIT(4)
+#define SSPCPSR			0x0010
+
+#define SSPIIR			0x0014
+#define SSPIIR_RIS		BIT(0)
+#define SSPIIR_TIS		BIT(1)
+#define SSPIIR_RORIS		BIT(2)
+#define SSPICR			SSPIIR
+
+/* timeout in milliseconds */
+#define SPI_TIMEOUT		5
+/* maximum depth of RX/TX FIFO */
+#define SPI_FIFO_SIZE		8
+
+/**
+ * struct ep93xx_spi - EP93xx SPI controller structure
+ * @lock: spinlock that protects concurrent accesses to fields @running,
+ *        @current_msg and @msg_queue
+ * @pdev: pointer to platform device
+ * @clk: clock for the controller
+ * @regs_base: pointer to ioremap()'d registers
+ * @irq: IRQ number used by the driver
+ * @min_rate: minimum clock rate (in Hz) supported by the controller
+ * @max_rate: maximum clock rate (in Hz) supported by the controller
+ * @running: is the queue running
+ * @wq: workqueue used by the driver
+ * @msg_work: work that is queued for the driver
+ * @wait: wait here until given transfer is completed
+ * @msg_queue: queue for the messages
+ * @current_msg: message that is currently processed (or %NULL if none)
+ * @tx: current byte in transfer to transmit
+ * @rx: current byte in transfer to receive
+ * @fifo_level: how full is FIFO (%0..%SPI_FIFO_SIZE - %1). Receiving one
+ *              frame decreases this level and sending one frame increases it.
+ *
+ * This structure holds EP93xx SPI controller specific information. When
+ * @running is %true, driver accepts transfer requests from protocol drivers.
+ * @current_msg is used to hold pointer to the message that is currently
+ * processed. If @current_msg is %NULL, it means that no processing is going
+ * on.
+ *
+ * Most of the fields are only written once and they can be accessed without
+ * taking the @lock. Fields that are accessed concurrently are: @current_msg,
+ * @running, and @msg_queue.
+ */
+struct ep93xx_spi {
+	spinlock_t			lock;
+	const struct platform_device	*pdev;
+	struct clk			*clk;
+	void __iomem			*regs_base;
+	int				irq;
+	unsigned long			min_rate;
+	unsigned long			max_rate;
+	bool				running;
+	struct workqueue_struct		*wq;
+	struct work_struct		msg_work;
+	struct completion		wait;
+	struct list_head		msg_queue;
+	struct spi_message		*current_msg;
+	size_t				tx;
+	size_t				rx;
+	size_t				fifo_level;
+};
+
+/**
+ * struct ep93xx_spi_chip - SPI device hardware settings
+ * @spi: back pointer to the SPI device
+ * @rate: max rate in hz this chip supports
+ * @div_cpsr: cpsr (pre-scaler) divider
+ * @div_scr: scr divider
+ * @dss: bits per word (4 - 16 bits)
+ * @ops: private chip operations
+ *
+ * This structure is used to store hardware register specific settings for each
+ * SPI device. Settings are written to hardware by function
+ * ep93xx_spi_chip_setup().
+ */
+struct ep93xx_spi_chip {
+	const struct spi_device		*spi;
+	unsigned long			rate;
+	u8				div_cpsr;
+	u8				div_scr;
+	u8				dss;
+	struct ep93xx_spi_chip_ops	*ops;
+};
+
+/* converts bits per word to CR0.DSS value */
+#define bits_per_word_to_dss(bpw)	((bpw) - 1)
+
+static inline void
+ep93xx_spi_write_u8(const struct ep93xx_spi *espi, u16 reg, u8 value)
+{
+	__raw_writeb(value, espi->regs_base + reg);
+}
+
+static inline u8
+ep93xx_spi_read_u8(const struct ep93xx_spi *spi, u16 reg)
+{
+	return __raw_readb(spi->regs_base + reg);
+}
+
+static inline void
+ep93xx_spi_write_u16(const struct ep93xx_spi *espi, u16 reg, u16 value)
+{
+	__raw_writew(value, espi->regs_base + reg);
+}
+
+static inline u16
+ep93xx_spi_read_u16(const struct ep93xx_spi *spi, u16 reg)
+{
+	return __raw_readw(spi->regs_base + reg);
+}
+
+static int ep93xx_spi_enable(const struct ep93xx_spi *espi)
+{
+	u8 regval;
+	int err;
+
+	err = clk_enable(espi->clk);
+	if (err)
+		return err;
+
+	regval = ep93xx_spi_read_u8(espi, SSPCR1);
+	regval |= SSPCR1_SSE;
+	ep93xx_spi_write_u8(espi, SSPCR1, regval);
+
+	return 0;
+}
+
+static void ep93xx_spi_disable(const struct ep93xx_spi *espi)
+{
+	u8 regval;
+
+	regval = ep93xx_spi_read_u8(espi, SSPCR1);
+	regval &= ~SSPCR1_SSE;
+	ep93xx_spi_write_u8(espi, SSPCR1, regval);
+
+	clk_disable(espi->clk);
+}
+
+static void ep93xx_spi_enable_interrupts(const struct ep93xx_spi *espi)
+{
+	u8 regval;
+
+	regval = ep93xx_spi_read_u8(espi, SSPCR1);
+	regval |= (SSPCR1_RORIE | SSPCR1_TIE | SSPCR1_RIE);
+	ep93xx_spi_write_u8(espi, SSPCR1, regval);
+}
+
+static void ep93xx_spi_disable_interrupts(const struct ep93xx_spi *espi)
+{
+	u8 regval;
+
+	regval = ep93xx_spi_read_u8(espi, SSPCR1);
+	regval &= ~(SSPCR1_RORIE | SSPCR1_TIE | SSPCR1_RIE);
+	ep93xx_spi_write_u8(espi, SSPCR1, regval);
+}
+
+/**
+ * ep93xx_spi_calc_divisors() - calculates SPI clock divisors
+ * @espi: ep93xx SPI controller struct
+ * @chip: divisors are calculated for this chip
+ * @rate: desired SPI output clock rate
+ *
+ * Function calculates cpsr (clock pre-scaler) and scr divisors based on
+ * given @rate and places them to @chip->div_cpsr and @chip->div_scr. If,
+ * for some reason, divisors cannot be calculated nothing is stored and
+ * %-EINVAL is returned.
+ */
+static int ep93xx_spi_calc_divisors(const struct ep93xx_spi *espi,
+				    struct ep93xx_spi_chip *chip,
+				    unsigned long rate)
+{
+	unsigned long spi_clk_rate = clk_get_rate(espi->clk);
+	int cpsr, scr;
+
+	/*
+	 * Make sure that max value is between values supported by the
+	 * controller. Note that minimum value is already checked in
+	 * ep93xx_spi_transfer().
+	 */
+	rate = clamp(rate, espi->min_rate, espi->max_rate);
+
+	/*
+	 * Calculate divisors so that we can get speed according the
+	 * following formula:
+	 *	rate = spi_clock_rate / (cpsr * (1 + scr))
+	 *
+	 * cpsr must be even number and starts from 2, scr can be any number
+	 * between 0 and 255.
+	 */
+	for (cpsr = 2; cpsr <= 254; cpsr += 2) {
+		for (scr = 0; scr <= 255; scr++) {
+			if ((spi_clk_rate / (cpsr * (scr + 1))) <= rate) {
+				chip->div_scr = (u8)scr;
+				chip->div_cpsr = (u8)cpsr;
+				return 0;
+			}
+		}
+	}
+
+	return -EINVAL;
+}
+
+static void ep93xx_spi_cs_control(struct spi_device *spi, bool control)
+{
+	struct ep93xx_spi_chip *chip = spi_get_ctldata(spi);
+	int value = (spi->mode & SPI_CS_HIGH) ? control : !control;
+
+	if (chip->ops && chip->ops->cs_control)
+		chip->ops->cs_control(spi, value);
+}
+
+/**
+ * ep93xx_spi_setup() - setup an SPI device
+ * @spi: SPI device to setup
+ *
+ * This function sets up SPI device mode, speed etc. Can be called multiple
+ * times for a single device. Returns %0 in case of success, negative error in
+ * case of failure. When this function returns success, the device is
+ * deselected.
+ */
+static int ep93xx_spi_setup(struct spi_device *spi)
+{
+	struct ep93xx_spi *espi = spi_master_get_devdata(spi->master);
+	struct ep93xx_spi_chip *chip;
+
+	if (spi->bits_per_word < 4 || spi->bits_per_word > 16) {
+		dev_err(&espi->pdev->dev, "invalid bits per word %d\n",
+			spi->bits_per_word);
+		return -EINVAL;
+	}
+
+	chip = spi_get_ctldata(spi);
+	if (!chip) {
+		dev_dbg(&espi->pdev->dev, "initial setup for %s\n",
+			spi->modalias);
+
+		chip = kzalloc(sizeof(*chip), GFP_KERNEL);
+		if (!chip)
+			return -ENOMEM;
+
+		chip->spi = spi;
+		chip->ops = spi->controller_data;
+
+		if (chip->ops && chip->ops->setup) {
+			int ret = chip->ops->setup(spi);
+			if (ret) {
+				kfree(chip);
+				return ret;
+			}
+		}
+
+		spi_set_ctldata(spi, chip);
+	}
+
+	if (spi->max_speed_hz != chip->rate) {
+		int err;
+
+		err = ep93xx_spi_calc_divisors(espi, chip, spi->max_speed_hz);
+		if (err != 0) {
+			spi_set_ctldata(spi, NULL);
+			kfree(chip);
+			return err;
+		}
+		chip->rate = spi->max_speed_hz;
+	}
+
+	chip->dss = bits_per_word_to_dss(spi->bits_per_word);
+
+	ep93xx_spi_cs_control(spi, false);
+	return 0;
+}
+
+/**
+ * ep93xx_spi_transfer() - queue message to be transferred
+ * @spi: target SPI device
+ * @msg: message to be transferred
+ *
+ * This function is called by SPI device drivers when they are going to transfer
+ * a new message. It simply puts the message in the queue and schedules
+ * workqueue to perform the actual transfer later on.
+ *
+ * Returns %0 on success and negative error in case of failure.
+ */
+static int ep93xx_spi_transfer(struct spi_device *spi, struct spi_message *msg)
+{
+	struct ep93xx_spi *espi = spi_master_get_devdata(spi->master);
+	struct spi_transfer *t;
+	unsigned long flags;
+
+	if (!msg || !msg->complete)
+		return -EINVAL;
+
+	/* first validate each transfer */
+	list_for_each_entry(t, &msg->transfers, transfer_list) {
+		if (t->bits_per_word) {
+			if (t->bits_per_word < 4 || t->bits_per_word > 16)
+				return -EINVAL;
+		}
+		if (t->speed_hz && t->speed_hz < espi->min_rate)
+				return -EINVAL;
+	}
+
+	/*
+	 * Now that we own the message, let's initialize it so that it is
+	 * suitable for us. We use @msg->status to signal whether there was
+	 * error in transfer and @msg->state is used to hold pointer to the
+	 * current transfer (or %NULL if no active current transfer).
+	 */
+	msg->state = NULL;
+	msg->status = 0;
+	msg->actual_length = 0;
+
+	spin_lock_irqsave(&espi->lock, flags);
+	if (!espi->running) {
+		spin_unlock_irqrestore(&espi->lock, flags);
+		return -ESHUTDOWN;
+	}
+	list_add_tail(&msg->queue, &espi->msg_queue);
+	queue_work(espi->wq, &espi->msg_work);
+	spin_unlock_irqrestore(&espi->lock, flags);
+
+	return 0;
+}
+
+/**
+ * ep93xx_spi_cleanup() - cleans up master controller specific state
+ * @spi: SPI device to cleanup
+ *
+ * This function releases master controller specific state for given @spi
+ * device.
+ */
+static void ep93xx_spi_cleanup(struct spi_device *spi)
+{
+	struct ep93xx_spi_chip *chip;
+
+	chip = spi_get_ctldata(spi);
+	if (chip) {
+		if (chip->ops && chip->ops->cleanup)
+			chip->ops->cleanup(spi);
+		spi_set_ctldata(spi, NULL);
+		kfree(chip);
+	}
+}
+
+/**
+ * ep93xx_spi_chip_setup() - configures hardware according to given @chip
+ * @espi: ep93xx SPI controller struct
+ * @chip: chip specific settings
+ *
+ * This function sets up the actual hardware registers with settings given in
+ * @chip. Note that no validation is done so make sure that callers validate
+ * settings before calling this.
+ */
+static void ep93xx_spi_chip_setup(const struct ep93xx_spi *espi,
+				  const struct ep93xx_spi_chip *chip)
+{
+	u16 cr0;
+
+	cr0 = chip->div_scr << SSPCR0_SCR_SHIFT;
+	cr0 |= (chip->spi->mode & (SPI_CPHA|SPI_CPOL)) << SSPCR0_MODE_SHIFT;
+	cr0 |= chip->dss;
+
+	dev_dbg(&espi->pdev->dev, "setup: mode %d, cpsr %d, scr %d, dss %d\n",
+		chip->spi->mode, chip->div_cpsr, chip->div_scr, chip->dss);
+	dev_dbg(&espi->pdev->dev, "setup: cr0 %#x", cr0);
+
+	ep93xx_spi_write_u8(espi, SSPCPSR, chip->div_cpsr);
+	ep93xx_spi_write_u16(espi, SSPCR0, cr0);
+}
+
+static inline int bits_per_word(const struct ep93xx_spi *espi)
+{
+	struct spi_message *msg = espi->current_msg;
+	struct spi_transfer *t = msg->state;
+
+	return t->bits_per_word ? t->bits_per_word : msg->spi->bits_per_word;
+}
+
+static void ep93xx_do_write(struct ep93xx_spi *espi, struct spi_transfer *t)
+{
+	if (bits_per_word(espi) > 8) {
+		u16 tx_val = 0;
+
+		if (t->tx_buf)
+			tx_val = ((u16 *)t->tx_buf)[espi->tx];
+		ep93xx_spi_write_u16(espi, SSPDR, tx_val);
+		espi->tx += sizeof(tx_val);
+	} else {
+		u8 tx_val = 0;
+
+		if (t->tx_buf)
+			tx_val = ((u8 *)t->tx_buf)[espi->tx];
+		ep93xx_spi_write_u8(espi, SSPDR, tx_val);
+		espi->tx += sizeof(tx_val);
+	}
+}
+
+static void ep93xx_do_read(struct ep93xx_spi *espi, struct spi_transfer *t)
+{
+	if (bits_per_word(espi) > 8) {
+		u16 rx_val;
+
+		rx_val = ep93xx_spi_read_u16(espi, SSPDR);
+		if (t->rx_buf)
+			((u16 *)t->rx_buf)[espi->rx] = rx_val;
+		espi->rx += sizeof(rx_val);
+	} else {
+		u8 rx_val;
+
+		rx_val = ep93xx_spi_read_u8(espi, SSPDR);
+		if (t->rx_buf)
+			((u8 *)t->rx_buf)[espi->rx] = rx_val;
+		espi->rx += sizeof(rx_val);
+	}
+}
+
+/**
+ * ep93xx_spi_read_write() - perform next RX/TX transfer
+ * @espi: ep93xx SPI controller struct
+ *
+ * This function transfers next bytes (or half-words) to/from RX/TX FIFOs. If
+ * called several times, the whole transfer will be completed. Returns
+ * %-EINPROGRESS when current transfer was not yet completed otherwise %0.
+ *
+ * When this function is finished, RX FIFO should be empty and TX FIFO should be
+ * full.
+ */
+static int ep93xx_spi_read_write(struct ep93xx_spi *espi)
+{
+	struct spi_message *msg = espi->current_msg;
+	struct spi_transfer *t = msg->state;
+
+	/* read as long as RX FIFO has frames in it */
+	while ((ep93xx_spi_read_u8(espi, SSPSR) & SSPSR_RNE)) {
+		ep93xx_do_read(espi, t);
+		espi->fifo_level--;
+	}
+
+	/* write as long as TX FIFO has room */
+	while (espi->fifo_level < SPI_FIFO_SIZE && espi->tx < t->len) {
+		ep93xx_do_write(espi, t);
+		espi->fifo_level++;
+	}
+
+	if (espi->rx == t->len) {
+		msg->actual_length += t->len;
+		return 0;
+	}
+
+	return -EINPROGRESS;
+}
+
+/**
+ * ep93xx_spi_process_transfer() - processes one SPI transfer
+ * @espi: ep93xx SPI controller struct
+ * @msg: current message
+ * @t: transfer to process
+ *
+ * This function processes one SPI transfer given in @t. Function waits until
+ * transfer is complete (may sleep) and updates @msg->status based on whether
+ * transfer was succesfully processed or not.
+ */
+static void ep93xx_spi_process_transfer(struct ep93xx_spi *espi,
+					struct spi_message *msg,
+					struct spi_transfer *t)
+{
+	struct ep93xx_spi_chip *chip = spi_get_ctldata(msg->spi);
+
+	msg->state = t;
+
+	/*
+	 * Handle any transfer specific settings if needed. We use
+	 * temporary chip settings here and restore original later when
+	 * the transfer is finished.
+	 */
+	if (t->speed_hz || t->bits_per_word) {
+		struct ep93xx_spi_chip tmp_chip = *chip;
+
+		if (t->speed_hz) {
+			int err;
+
+			err = ep93xx_spi_calc_divisors(espi, &tmp_chip,
+						       t->speed_hz);
+			if (err) {
+				dev_err(&espi->pdev->dev,
+					"failed to adjust speed\n");
+				msg->status = err;
+				return;
+			}
+		}
+
+		if (t->bits_per_word)
+			tmp_chip.dss = bits_per_word_to_dss(t->bits_per_word);
+
+		/*
+		 * Set up temporary new hw settings for this transfer.
+		 */
+		ep93xx_spi_chip_setup(espi, &tmp_chip);
+	}
+
+	espi->rx = 0;
+	espi->tx = 0;
+
+	/*
+	 * Now everything is set up for the current transfer. We prime the TX
+	 * FIFO, enable interrupts, and wait for the transfer to complete.
+	 */
+	if (ep93xx_spi_read_write(espi)) {
+		ep93xx_spi_enable_interrupts(espi);
+		wait_for_completion(&espi->wait);
+	}
+
+	/*
+	 * In case of error during transmit, we bail out from processing
+	 * the message.
+	 */
+	if (msg->status)
+		return;
+
+	/*
+	 * After this transfer is finished, perform any possible
+	 * post-transfer actions requested by the protocol driver.
+	 */
+	if (t->delay_usecs) {
+		set_current_state(TASK_UNINTERRUPTIBLE);
+		schedule_timeout(usecs_to_jiffies(t->delay_usecs));
+	}
+	if (t->cs_change) {
+		if (!list_is_last(&t->transfer_list, &msg->transfers)) {
+			/*
+			 * In case protocol driver is asking us to drop the
+			 * chipselect briefly, we let the scheduler to handle
+			 * any "delay" here.
+			 */
+			ep93xx_spi_cs_control(msg->spi, false);
+			cond_resched();
+			ep93xx_spi_cs_control(msg->spi, true);
+		}
+	}
+
+	if (t->speed_hz || t->bits_per_word)
+		ep93xx_spi_chip_setup(espi, chip);
+}
+
+/*
+ * ep93xx_spi_process_message() - process one SPI message
+ * @espi: ep93xx SPI controller struct
+ * @msg: message to process
+ *
+ * This function processes a single SPI message. We go through all transfers in
+ * the message and pass them to ep93xx_spi_process_transfer(). Chipselect is
+ * asserted during the whole message (unless per transfer cs_change is set).
+ *
+ * @msg->status contains %0 in case of success or negative error code in case of
+ * failure.
+ */
+static void ep93xx_spi_process_message(struct ep93xx_spi *espi,
+				       struct spi_message *msg)
+{
+	unsigned long timeout;
+	struct spi_transfer *t;
+	int err;
+
+	/*
+	 * Enable the SPI controller and its clock.
+	 */
+	err = ep93xx_spi_enable(espi);
+	if (err) {
+		dev_err(&espi->pdev->dev, "failed to enable SPI controller\n");
+		msg->status = err;
+		return;
+	}
+
+	/*
+	 * Just to be sure: flush any data from RX FIFO.
+	 */
+	timeout = jiffies + msecs_to_jiffies(SPI_TIMEOUT);
+	while (ep93xx_spi_read_u16(espi, SSPSR) & SSPSR_RNE) {
+		if (time_after(jiffies, timeout)) {
+			dev_warn(&espi->pdev->dev,
+				 "timeout while flushing RX FIFO\n");
+			msg->status = -ETIMEDOUT;
+			return;
+		}
+		ep93xx_spi_read_u16(espi, SSPDR);
+	}
+
+	/*
+	 * We explicitly handle FIFO level. This way we don't have to check TX
+	 * FIFO status using %SSPSR_TNF bit which may cause RX FIFO overruns.
+	 */
+	espi->fifo_level = 0;
+
+	/*
+	 * Update SPI controller registers according to spi device and assert
+	 * the chipselect.
+	 */
+	ep93xx_spi_chip_setup(espi, spi_get_ctldata(msg->spi));
+	ep93xx_spi_cs_control(msg->spi, true);
+
+	list_for_each_entry(t, &msg->transfers, transfer_list) {
+		ep93xx_spi_process_transfer(espi, msg, t);
+		if (msg->status)
+			break;
+	}
+
+	/*
+	 * Now the whole message is transferred (or failed for some reason). We
+	 * deselect the device and disable the SPI controller.
+	 */
+	ep93xx_spi_cs_control(msg->spi, false);
+	ep93xx_spi_disable(espi);
+}
+
+#define work_to_espi(work) (container_of((work), struct ep93xx_spi, msg_work))
+
+/**
+ * ep93xx_spi_work() - EP93xx SPI workqueue worker function
+ * @work: work struct
+ *
+ * Workqueue worker function. This function is called when there are new
+ * SPI messages to be processed. Message is taken out from the queue and then
+ * passed to ep93xx_spi_process_message().
+ *
+ * After message is transferred, protocol driver is notified by calling
+ * @msg->complete(). In case of error, @msg->status is set to negative error
+ * number, otherwise it contains zero (and @msg->actual_length is updated).
+ */
+static void ep93xx_spi_work(struct work_struct *work)
+{
+	struct ep93xx_spi *espi = work_to_espi(work);
+	struct spi_message *msg;
+
+	spin_lock_irq(&espi->lock);
+	if (!espi->running || espi->current_msg ||
+		list_empty(&espi->msg_queue)) {
+		spin_unlock_irq(&espi->lock);
+		return;
+	}
+	msg = list_first_entry(&espi->msg_queue, struct spi_message, queue);
+	list_del_init(&msg->queue);
+	espi->current_msg = msg;
+	spin_unlock_irq(&espi->lock);
+
+	ep93xx_spi_process_message(espi, msg);
+
+	/*
+	 * Update the current message and re-schedule ourselves if there are
+	 * more messages in the queue.
+	 */
+	spin_lock_irq(&espi->lock);
+	espi->current_msg = NULL;
+	if (espi->running && !list_empty(&espi->msg_queue))
+		queue_work(espi->wq, &espi->msg_work);
+	spin_unlock_irq(&espi->lock);
+
+	/* notify the protocol driver that we are done with this message */
+	msg->complete(msg->context);
+}
+
+static irqreturn_t ep93xx_spi_interrupt(int irq, void *dev_id)
+{
+	struct ep93xx_spi *espi = dev_id;
+	u8 irq_status = ep93xx_spi_read_u8(espi, SSPIIR);
+
+	/*
+	 * If we got ROR (receive overrun) interrupt we know that something is
+	 * wrong. Just abort the message.
+	 */
+	if (unlikely(irq_status & SSPIIR_RORIS)) {
+		/* clear the overrun interrupt */
+		ep93xx_spi_write_u8(espi, SSPICR, 0);
+		dev_warn(&espi->pdev->dev,
+			 "receive overrun, aborting the message\n");
+		espi->current_msg->status = -EIO;
+	} else {
+		/*
+		 * Interrupt is either RX (RIS) or TX (TIS). For both cases we
+		 * simply execute next data transfer.
+		 */
+		if (ep93xx_spi_read_write(espi)) {
+			/*
+			 * In normal case, there still is some processing left
+			 * for current transfer. Let's wait for the next
+			 * interrupt then.
+			 */
+			return IRQ_HANDLED;
+		}
+	}
+
+	/*
+	 * Current transfer is finished, either with error or with success. In
+	 * any case we disable interrupts and notify the worker to handle
+	 * any post-processing of the message.
+	 */
+	ep93xx_spi_disable_interrupts(espi);
+	complete(&espi->wait);
+	return IRQ_HANDLED;
+}
+
+static int __init ep93xx_spi_probe(struct platform_device *pdev)
+{
+	struct spi_master *master;
+	struct ep93xx_spi_info *info;
+	struct ep93xx_spi *espi;
+	struct resource *res;
+	int error;
+
+	info = pdev->dev.platform_data;
+
+	master = spi_alloc_master(&pdev->dev, sizeof(*espi));
+	if (!master) {
+		dev_err(&pdev->dev, "failed to allocate spi master\n");
+		return -ENOMEM;
+	}
+
+	master->setup = ep93xx_spi_setup;
+	master->transfer = ep93xx_spi_transfer;
+	master->cleanup = ep93xx_spi_cleanup;
+	master->bus_num = pdev->id;
+	master->num_chipselect = info->num_chipselect;
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
+
+	platform_set_drvdata(pdev, master);
+
+	espi = spi_master_get_devdata(master);
+
+	espi->clk = clk_get(&pdev->dev, NULL);
+	if (IS_ERR(espi->clk)) {
+		dev_err(&pdev->dev, "unable to get spi clock\n");
+		error = PTR_ERR(espi->clk);
+		goto fail_release_master;
+	}
+
+	spin_lock_init(&espi->lock);
+	init_completion(&espi->wait);
+
+	/*
+	 * Calculate maximum and minimum supported clock rates
+	 * for the controller.
+	 */
+	espi->max_rate = clk_get_rate(espi->clk) / 2;
+	espi->min_rate = clk_get_rate(espi->clk) / (254 * 256);
+	espi->pdev = pdev;
+
+	espi->irq = platform_get_irq(pdev, 0);
+	if (espi->irq < 0) {
+		error = -EBUSY;
+		dev_err(&pdev->dev, "failed to get irq resources\n");
+		goto fail_put_clock;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "unable to get iomem resource\n");
+		error = -ENODEV;
+		goto fail_put_clock;
+	}
+
+	res = request_mem_region(res->start, resource_size(res), pdev->name);
+	if (!res) {
+		dev_err(&pdev->dev, "unable to request iomem resources\n");
+		error = -EBUSY;
+		goto fail_put_clock;
+	}
+
+	espi->regs_base = ioremap(res->start, resource_size(res));
+	if (!espi->regs_base) {
+		dev_err(&pdev->dev, "failed to map resources\n");
+		error = -ENODEV;
+		goto fail_free_mem;
+	}
+
+	error = request_irq(espi->irq, ep93xx_spi_interrupt, 0,
+			    "ep93xx-spi", espi);
+	if (error) {
+		dev_err(&pdev->dev, "failed to request irq\n");
+		goto fail_unmap_regs;
+	}
+
+	espi->wq = create_singlethread_workqueue("ep93xx_spid");
+	if (!espi->wq) {
+		dev_err(&pdev->dev, "unable to create workqueue\n");
+		goto fail_free_irq;
+	}
+	INIT_WORK(&espi->msg_work, ep93xx_spi_work);
+	INIT_LIST_HEAD(&espi->msg_queue);
+	espi->running = true;
+
+	/* make sure that the hardware is disabled */
+	ep93xx_spi_write_u8(espi, SSPCR1, 0);
+
+	error = spi_register_master(master);
+	if (error) {
+		dev_err(&pdev->dev, "failed to register SPI master\n");
+		goto fail_free_queue;
+	}
+
+	dev_info(&pdev->dev, "EP93xx SPI Controller at 0x%08lx irq %d\n",
+		 (unsigned long)res->start, espi->irq);
+
+	return 0;
+
+fail_free_queue:
+	destroy_workqueue(espi->wq);
+fail_free_irq:
+	free_irq(espi->irq, espi);
+fail_unmap_regs:
+	iounmap(espi->regs_base);
+fail_free_mem:
+	release_mem_region(res->start, resource_size(res));
+fail_put_clock:
+	clk_put(espi->clk);
+fail_release_master:
+	spi_master_put(master);
+	platform_set_drvdata(pdev, NULL);
+
+	return error;
+}
+
+static int __exit ep93xx_spi_remove(struct platform_device *pdev)
+{
+	struct spi_master *master = platform_get_drvdata(pdev);
+	struct ep93xx_spi *espi = spi_master_get_devdata(master);
+	struct resource *res;
+
+	spin_lock_irq(&espi->lock);
+	espi->running = false;
+	spin_unlock_irq(&espi->lock);
+
+	destroy_workqueue(espi->wq);
+
+	/*
+	 * Complete remaining messages with %-ESHUTDOWN status.
+	 */
+	spin_lock_irq(&espi->lock);
+	while (!list_empty(&espi->msg_queue)) {
+		struct spi_message *msg;
+
+		msg = list_first_entry(&espi->msg_queue,
+				       struct spi_message, queue);
+		list_del_init(&msg->queue);
+		msg->status = -ESHUTDOWN;
+		spin_unlock_irq(&espi->lock);
+		msg->complete(msg->context);
+		spin_lock_irq(&espi->lock);
+	}
+	spin_unlock_irq(&espi->lock);
+
+	free_irq(espi->irq, espi);
+	iounmap(espi->regs_base);
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	release_mem_region(res->start, resource_size(res));
+	clk_put(espi->clk);
+	platform_set_drvdata(pdev, NULL);
+
+	spi_unregister_master(master);
+	return 0;
+}
+
+static struct platform_driver ep93xx_spi_driver = {
+	.driver		= {
+		.name	= "ep93xx-spi",
+		.owner	= THIS_MODULE,
+	},
+	.remove		= __exit_p(ep93xx_spi_remove),
+};
+
+static int __init ep93xx_spi_init(void)
+{
+	return platform_driver_probe(&ep93xx_spi_driver, ep93xx_spi_probe);
+}
+module_init(ep93xx_spi_init);
+
+static void __exit ep93xx_spi_exit(void)
+{
+	platform_driver_unregister(&ep93xx_spi_driver);
+}
+module_exit(ep93xx_spi_exit);
+
+MODULE_DESCRIPTION("EP93xx SPI Controller driver");
+MODULE_AUTHOR("Mika Westerberg <mika.westerberg-X3B1VOXEql0@public.gmane.org>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:ep93xx-spi");
-- 
1.5.6.5


------------------------------------------------------------------------------

[PATCH v7 1/2] spi: implemented driver for Cirrus EP93xx SPI controller

[Mika Westerberg]

This patch adds an SPI master driver for the Cirrus EP93xx SPI controller found
in EP93xx chips.

Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi>
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ryan Mallon <ryan@bluewatersys.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Martin Guy <martinwguy@gmail.com>
---
 Documentation/spi/ep93xx_spi                   |   95 +++
 arch/arm/mach-ep93xx/include/mach/ep93xx_spi.h |   27 +
 drivers/spi/Kconfig                            |   10 +
 drivers/spi/Makefile                           |    1 +
 drivers/spi/ep93xx_spi.c                       |  938 ++++++++++++++++++++++++
 5 files changed, 1071 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/spi/ep93xx_spi
 create mode 100644 arch/arm/mach-ep93xx/include/mach/ep93xx_spi.h
 create mode 100644 drivers/spi/ep93xx_spi.c

diff --git a/Documentation/spi/ep93xx_spi b/Documentation/spi/ep93xx_spi
new file mode 100644
index 0000000..6325f5b
--- /dev/null
+++ b/Documentation/spi/ep93xx_spi
@@ -0,0 +1,95 @@
+Cirrus EP93xx SPI controller driver HOWTO
+=========================================
+
+ep93xx_spi driver brings SPI master support for EP93xx SPI controller.  Chip
+selects are implemented with GPIO lines.
+
+NOTE: If possible, don't use SFRMOUT (SFRM1) signal as a chip select. It will
+not work correctly (it cannot be controlled by software). Use GPIO lines
+instead.
+
+Sample configuration
+====================
+
+Typically driver configuration is done in platform board files (the files under
+arch/arm/mach-ep93xx/*.c). In this example we configure MMC over SPI through
+this driver on TS-7260 board. You can adapt the code to suit your needs.
+
+This example uses EGPIO9 as SD/MMC card chip select (this is wired in DIO1
+header on the board).
+
+You need to select CONFIG_MMC_SPI to use mmc_spi driver.
+
+arch/arm/mach-ep93xx/ts72xx.c:
+
+...
+#include <linux/gpio.h>
+#include <linux/spi/spi.h>
+
+#include <mach/ep93xx_spi.h>
+
+/* this is our GPIO line used for chip select */
+#define MMC_CHIP_SELECT_GPIO EP93XX_GPIO_LINE_EGPIO9
+
+static int ts72xx_mmc_spi_setup(struct spi_device *spi)
+{
+	int err;
+
+	err = gpio_request(MMC_CHIP_SELECT_GPIO, spi->modalias);
+	if (err)
+		return err;
+
+	gpio_direction_output(MMC_CHIP_SELECT_GPIO, 1);
+
+	return 0;
+}
+
+static void ts72xx_mmc_spi_cleanup(struct spi_device *spi)
+{
+	gpio_set_value(MMC_CHIP_SELECT_GPIO, 1);
+	gpio_direction_input(MMC_CHIP_SELECT_GPIO);
+	gpio_free(MMC_CHIP_SELECT_GPIO);
+}
+
+static void ts72xx_mmc_spi_cs_control(struct spi_device *spi, int value)
+{
+	gpio_set_value(MMC_CHIP_SELECT_GPIO, value);
+}
+
+static struct ep93xx_spi_chip_ops ts72xx_mmc_spi_ops = {
+	.setup		= ts72xx_mmc_spi_setup,
+	.cleanup	= ts72xx_mmc_spi_cleanup,
+	.cs_control	= ts72xx_mmc_spi_cs_control,
+};
+
+static struct spi_board_info ts72xx_spi_devices[] __initdata = {
+	{
+		.modalias		= "mmc_spi",
+		.controller_data	= &ts72xx_mmc_spi_ops,
+		/*
+		 * We use 10 MHz even though the maximum is 7.4 MHz. The driver
+		 * will limit it automatically to max. frequency.
+		 */
+		.max_speed_hz		= 10 * 1000 * 1000,
+		.bus_num		= 0,
+		.chip_select		= 0,
+		.mode			= SPI_MODE_0,
+	},
+};
+
+static struct ep93xx_spi_info ts72xx_spi_info = {
+	.num_chipselect	= ARRAY_SIZE(ts72xx_spi_devices),
+};
+
+static void __init ts72xx_init_machine(void)
+{
+	...
+	ep93xx_register_spi(&ts72xx_spi_info, ts72xx_spi_devices,
+			    ARRAY_SIZE(ts72xx_spi_devices));
+}
+
+Thanks to
+=========
+Martin Guy, H. Hartley Sweeten and others who helped me during development of
+the driver. Simplemachines.it donated me a Sim.One board which I used testing
+the driver on EP9307.
diff --git a/arch/arm/mach-ep93xx/include/mach/ep93xx_spi.h b/arch/arm/mach-ep93xx/include/mach/ep93xx_spi.h
new file mode 100644
index 0000000..0a37961
--- /dev/null
+++ b/arch/arm/mach-ep93xx/include/mach/ep93xx_spi.h
@@ -0,0 +1,27 @@
+#ifndef __ASM_MACH_EP93XX_SPI_H
+#define __ASM_MACH_EP93XX_SPI_H
+
+struct spi_device;
+
+/**
+ * struct ep93xx_spi_info - EP93xx specific SPI descriptor
+ * @num_chipselect: number of chip selects on this board, must be
+ *                  at least one
+ */
+struct ep93xx_spi_info {
+	int	num_chipselect;
+};
+
+/**
+ * struct ep93xx_spi_chip_ops - operation callbacks for SPI slave device
+ * @setup: setup the chip select mechanism
+ * @cleanup: cleanup the chip select mechanism
+ * @cs_control: control the device chip select
+ */
+struct ep93xx_spi_chip_ops {
+	int	(*setup)(struct spi_device *spi);
+	void	(*cleanup)(struct spi_device *spi);
+	void	(*cs_control)(struct spi_device *spi, int value);
+};
+
+#endif /* __ASM_MACH_EP93XX_SPI_H */
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index a191fa2..2b2f4c3 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -117,6 +117,16 @@ config SPI_DAVINCI
 	help
 	  SPI master controller for DaVinci and DA8xx SPI modules.
 
+config SPI_EP93XX
+	tristate "Cirrus Logic EP93xx SPI controller"
+	depends on ARCH_EP93XX
+	help
+	  This enables using the Cirrus EP93xx SPI controller in master
+	  mode.
+
+	  To compile this driver as a module, choose M here. The module will be
+	  called ep93xx_spi.
+
 config SPI_GPIO
 	tristate "GPIO-based bitbanging SPI Master"
 	depends on GENERIC_GPIO
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index d7d0f89..377f845 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -21,6 +21,7 @@ obj-$(CONFIG_SPI_DAVINCI)		+= davinci_spi.o
 obj-$(CONFIG_SPI_DESIGNWARE)		+= dw_spi.o
 obj-$(CONFIG_SPI_DW_PCI)		+= dw_spi_pci.o
 obj-$(CONFIG_SPI_DW_MMIO)		+= dw_spi_mmio.o
+obj-$(CONFIG_SPI_EP93XX)		+= ep93xx_spi.o
 obj-$(CONFIG_SPI_GPIO)			+= spi_gpio.o
 obj-$(CONFIG_SPI_IMX)			+= spi_imx.o
 obj-$(CONFIG_SPI_LM70_LLP)		+= spi_lm70llp.o
diff --git a/drivers/spi/ep93xx_spi.c b/drivers/spi/ep93xx_spi.c
new file mode 100644
index 0000000..0ba35df
--- /dev/null
+++ b/drivers/spi/ep93xx_spi.c
@@ -0,0 +1,938 @@
+/*
+ * Driver for Cirrus Logic EP93xx SPI controller.
+ *
+ * Copyright (c) 2010 Mika Westerberg
+ *
+ * Explicit FIFO handling code was inspired by amba-pl022 driver.
+ *
+ * Chip select support using other than built-in GPIOs by H. Hartley Sweeten.
+ *
+ * For more information about the SPI controller see documentation on Cirrus
+ * Logic web site:
+ *     http://www.cirrus.com/en/pubs/manual/EP93xx_Users_Guide_UM1.pdf
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/bitops.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/workqueue.h>
+#include <linux/sched.h>
+#include <linux/spi/spi.h>
+
+#include <mach/ep93xx_spi.h>
+
+#define SSPCR0			0x0000
+#define SSPCR0_MODE_SHIFT	6
+#define SSPCR0_SCR_SHIFT	8
+
+#define SSPCR1			0x0004
+#define SSPCR1_RIE		BIT(0)
+#define SSPCR1_TIE		BIT(1)
+#define SSPCR1_RORIE		BIT(2)
+#define SSPCR1_LBM		BIT(3)
+#define SSPCR1_SSE		BIT(4)
+#define SSPCR1_MS		BIT(5)
+#define SSPCR1_SOD		BIT(6)
+
+#define SSPDR			0x0008
+
+#define SSPSR			0x000c
+#define SSPSR_TFE		BIT(0)
+#define SSPSR_TNF		BIT(1)
+#define SSPSR_RNE		BIT(2)
+#define SSPSR_RFF		BIT(3)
+#define SSPSR_BSY		BIT(4)
+#define SSPCPSR			0x0010
+
+#define SSPIIR			0x0014
+#define SSPIIR_RIS		BIT(0)
+#define SSPIIR_TIS		BIT(1)
+#define SSPIIR_RORIS		BIT(2)
+#define SSPICR			SSPIIR
+
+/* timeout in milliseconds */
+#define SPI_TIMEOUT		5
+/* maximum depth of RX/TX FIFO */
+#define SPI_FIFO_SIZE		8
+
+/**
+ * struct ep93xx_spi - EP93xx SPI controller structure
+ * @lock: spinlock that protects concurrent accesses to fields @running,
+ *        @current_msg and @msg_queue
+ * @pdev: pointer to platform device
+ * @clk: clock for the controller
+ * @regs_base: pointer to ioremap()'d registers
+ * @irq: IRQ number used by the driver
+ * @min_rate: minimum clock rate (in Hz) supported by the controller
+ * @max_rate: maximum clock rate (in Hz) supported by the controller
+ * @running: is the queue running
+ * @wq: workqueue used by the driver
+ * @msg_work: work that is queued for the driver
+ * @wait: wait here until given transfer is completed
+ * @msg_queue: queue for the messages
+ * @current_msg: message that is currently processed (or %NULL if none)
+ * @tx: current byte in transfer to transmit
+ * @rx: current byte in transfer to receive
+ * @fifo_level: how full is FIFO (%0..%SPI_FIFO_SIZE - %1). Receiving one
+ *              frame decreases this level and sending one frame increases it.
+ *
+ * This structure holds EP93xx SPI controller specific information. When
+ * @running is %true, driver accepts transfer requests from protocol drivers.
+ * @current_msg is used to hold pointer to the message that is currently
+ * processed. If @current_msg is %NULL, it means that no processing is going
+ * on.
+ *
+ * Most of the fields are only written once and they can be accessed without
+ * taking the @lock. Fields that are accessed concurrently are: @current_msg,
+ * @running, and @msg_queue.
+ */
+struct ep93xx_spi {
+	spinlock_t			lock;
+	const struct platform_device	*pdev;
+	struct clk			*clk;
+	void __iomem			*regs_base;
+	int				irq;
+	unsigned long			min_rate;
+	unsigned long			max_rate;
+	bool				running;
+	struct workqueue_struct		*wq;
+	struct work_struct		msg_work;
+	struct completion		wait;
+	struct list_head		msg_queue;
+	struct spi_message		*current_msg;
+	size_t				tx;
+	size_t				rx;
+	size_t				fifo_level;
+};
+
+/**
+ * struct ep93xx_spi_chip - SPI device hardware settings
+ * @spi: back pointer to the SPI device
+ * @rate: max rate in hz this chip supports
+ * @div_cpsr: cpsr (pre-scaler) divider
+ * @div_scr: scr divider
+ * @dss: bits per word (4 - 16 bits)
+ * @ops: private chip operations
+ *
+ * This structure is used to store hardware register specific settings for each
+ * SPI device. Settings are written to hardware by function
+ * ep93xx_spi_chip_setup().
+ */
+struct ep93xx_spi_chip {
+	const struct spi_device		*spi;
+	unsigned long			rate;
+	u8				div_cpsr;
+	u8				div_scr;
+	u8				dss;
+	struct ep93xx_spi_chip_ops	*ops;
+};
+
+/* converts bits per word to CR0.DSS value */
+#define bits_per_word_to_dss(bpw)	((bpw) - 1)
+
+static inline void
+ep93xx_spi_write_u8(const struct ep93xx_spi *espi, u16 reg, u8 value)
+{
+	__raw_writeb(value, espi->regs_base + reg);
+}
+
+static inline u8
+ep93xx_spi_read_u8(const struct ep93xx_spi *spi, u16 reg)
+{
+	return __raw_readb(spi->regs_base + reg);
+}
+
+static inline void
+ep93xx_spi_write_u16(const struct ep93xx_spi *espi, u16 reg, u16 value)
+{
+	__raw_writew(value, espi->regs_base + reg);
+}
+
+static inline u16
+ep93xx_spi_read_u16(const struct ep93xx_spi *spi, u16 reg)
+{
+	return __raw_readw(spi->regs_base + reg);
+}
+
+static int ep93xx_spi_enable(const struct ep93xx_spi *espi)
+{
+	u8 regval;
+	int err;
+
+	err = clk_enable(espi->clk);
+	if (err)
+		return err;
+
+	regval = ep93xx_spi_read_u8(espi, SSPCR1);
+	regval |= SSPCR1_SSE;
+	ep93xx_spi_write_u8(espi, SSPCR1, regval);
+
+	return 0;
+}
+
+static void ep93xx_spi_disable(const struct ep93xx_spi *espi)
+{
+	u8 regval;
+
+	regval = ep93xx_spi_read_u8(espi, SSPCR1);
+	regval &= ~SSPCR1_SSE;
+	ep93xx_spi_write_u8(espi, SSPCR1, regval);
+
+	clk_disable(espi->clk);
+}
+
+static void ep93xx_spi_enable_interrupts(const struct ep93xx_spi *espi)
+{
+	u8 regval;
+
+	regval = ep93xx_spi_read_u8(espi, SSPCR1);
+	regval |= (SSPCR1_RORIE | SSPCR1_TIE | SSPCR1_RIE);
+	ep93xx_spi_write_u8(espi, SSPCR1, regval);
+}
+
+static void ep93xx_spi_disable_interrupts(const struct ep93xx_spi *espi)
+{
+	u8 regval;
+
+	regval = ep93xx_spi_read_u8(espi, SSPCR1);
+	regval &= ~(SSPCR1_RORIE | SSPCR1_TIE | SSPCR1_RIE);
+	ep93xx_spi_write_u8(espi, SSPCR1, regval);
+}
+
+/**
+ * ep93xx_spi_calc_divisors() - calculates SPI clock divisors
+ * @espi: ep93xx SPI controller struct
+ * @chip: divisors are calculated for this chip
+ * @rate: desired SPI output clock rate
+ *
+ * Function calculates cpsr (clock pre-scaler) and scr divisors based on
+ * given @rate and places them to @chip->div_cpsr and @chip->div_scr. If,
+ * for some reason, divisors cannot be calculated nothing is stored and
+ * %-EINVAL is returned.
+ */
+static int ep93xx_spi_calc_divisors(const struct ep93xx_spi *espi,
+				    struct ep93xx_spi_chip *chip,
+				    unsigned long rate)
+{
+	unsigned long spi_clk_rate = clk_get_rate(espi->clk);
+	int cpsr, scr;
+
+	/*
+	 * Make sure that max value is between values supported by the
+	 * controller. Note that minimum value is already checked in
+	 * ep93xx_spi_transfer().
+	 */
+	rate = clamp(rate, espi->min_rate, espi->max_rate);
+
+	/*
+	 * Calculate divisors so that we can get speed according the
+	 * following formula:
+	 *	rate = spi_clock_rate / (cpsr * (1 + scr))
+	 *
+	 * cpsr must be even number and starts from 2, scr can be any number
+	 * between 0 and 255.
+	 */
+	for (cpsr = 2; cpsr <= 254; cpsr += 2) {
+		for (scr = 0; scr <= 255; scr++) {
+			if ((spi_clk_rate / (cpsr * (scr + 1))) <= rate) {
+				chip->div_scr = (u8)scr;
+				chip->div_cpsr = (u8)cpsr;
+				return 0;
+			}
+		}
+	}
+
+	return -EINVAL;
+}
+
+static void ep93xx_spi_cs_control(struct spi_device *spi, bool control)
+{
+	struct ep93xx_spi_chip *chip = spi_get_ctldata(spi);
+	int value = (spi->mode & SPI_CS_HIGH) ? control : !control;
+
+	if (chip->ops && chip->ops->cs_control)
+		chip->ops->cs_control(spi, value);
+}
+
+/**
+ * ep93xx_spi_setup() - setup an SPI device
+ * @spi: SPI device to setup
+ *
+ * This function sets up SPI device mode, speed etc. Can be called multiple
+ * times for a single device. Returns %0 in case of success, negative error in
+ * case of failure. When this function returns success, the device is
+ * deselected.
+ */
+static int ep93xx_spi_setup(struct spi_device *spi)
+{
+	struct ep93xx_spi *espi = spi_master_get_devdata(spi->master);
+	struct ep93xx_spi_chip *chip;
+
+	if (spi->bits_per_word < 4 || spi->bits_per_word > 16) {
+		dev_err(&espi->pdev->dev, "invalid bits per word %d\n",
+			spi->bits_per_word);
+		return -EINVAL;
+	}
+
+	chip = spi_get_ctldata(spi);
+	if (!chip) {
+		dev_dbg(&espi->pdev->dev, "initial setup for %s\n",
+			spi->modalias);
+
+		chip = kzalloc(sizeof(*chip), GFP_KERNEL);
+		if (!chip)
+			return -ENOMEM;
+
+		chip->spi = spi;
+		chip->ops = spi->controller_data;
+
+		if (chip->ops && chip->ops->setup) {
+			int ret = chip->ops->setup(spi);
+			if (ret) {
+				kfree(chip);
+				return ret;
+			}
+		}
+
+		spi_set_ctldata(spi, chip);
+	}
+
+	if (spi->max_speed_hz != chip->rate) {
+		int err;
+
+		err = ep93xx_spi_calc_divisors(espi, chip, spi->max_speed_hz);
+		if (err != 0) {
+			spi_set_ctldata(spi, NULL);
+			kfree(chip);
+			return err;
+		}
+		chip->rate = spi->max_speed_hz;
+	}
+
+	chip->dss = bits_per_word_to_dss(spi->bits_per_word);
+
+	ep93xx_spi_cs_control(spi, false);
+	return 0;
+}
+
+/**
+ * ep93xx_spi_transfer() - queue message to be transferred
+ * @spi: target SPI device
+ * @msg: message to be transferred
+ *
+ * This function is called by SPI device drivers when they are going to transfer
+ * a new message. It simply puts the message in the queue and schedules
+ * workqueue to perform the actual transfer later on.
+ *
+ * Returns %0 on success and negative error in case of failure.
+ */
+static int ep93xx_spi_transfer(struct spi_device *spi, struct spi_message *msg)
+{
+	struct ep93xx_spi *espi = spi_master_get_devdata(spi->master);
+	struct spi_transfer *t;
+	unsigned long flags;
+
+	if (!msg || !msg->complete)
+		return -EINVAL;
+
+	/* first validate each transfer */
+	list_for_each_entry(t, &msg->transfers, transfer_list) {
+		if (t->bits_per_word) {
+			if (t->bits_per_word < 4 || t->bits_per_word > 16)
+				return -EINVAL;
+		}
+		if (t->speed_hz && t->speed_hz < espi->min_rate)
+				return -EINVAL;
+	}
+
+	/*
+	 * Now that we own the message, let's initialize it so that it is
+	 * suitable for us. We use @msg->status to signal whether there was
+	 * error in transfer and @msg->state is used to hold pointer to the
+	 * current transfer (or %NULL if no active current transfer).
+	 */
+	msg->state = NULL;
+	msg->status = 0;
+	msg->actual_length = 0;
+
+	spin_lock_irqsave(&espi->lock, flags);
+	if (!espi->running) {
+		spin_unlock_irqrestore(&espi->lock, flags);
+		return -ESHUTDOWN;
+	}
+	list_add_tail(&msg->queue, &espi->msg_queue);
+	queue_work(espi->wq, &espi->msg_work);
+	spin_unlock_irqrestore(&espi->lock, flags);
+
+	return 0;
+}
+
+/**
+ * ep93xx_spi_cleanup() - cleans up master controller specific state
+ * @spi: SPI device to cleanup
+ *
+ * This function releases master controller specific state for given @spi
+ * device.
+ */
+static void ep93xx_spi_cleanup(struct spi_device *spi)
+{
+	struct ep93xx_spi_chip *chip;
+
+	chip = spi_get_ctldata(spi);
+	if (chip) {
+		if (chip->ops && chip->ops->cleanup)
+			chip->ops->cleanup(spi);
+		spi_set_ctldata(spi, NULL);
+		kfree(chip);
+	}
+}
+
+/**
+ * ep93xx_spi_chip_setup() - configures hardware according to given @chip
+ * @espi: ep93xx SPI controller struct
+ * @chip: chip specific settings
+ *
+ * This function sets up the actual hardware registers with settings given in
+ * @chip. Note that no validation is done so make sure that callers validate
+ * settings before calling this.
+ */
+static void ep93xx_spi_chip_setup(const struct ep93xx_spi *espi,
+				  const struct ep93xx_spi_chip *chip)
+{
+	u16 cr0;
+
+	cr0 = chip->div_scr << SSPCR0_SCR_SHIFT;
+	cr0 |= (chip->spi->mode & (SPI_CPHA|SPI_CPOL)) << SSPCR0_MODE_SHIFT;
+	cr0 |= chip->dss;
+
+	dev_dbg(&espi->pdev->dev, "setup: mode %d, cpsr %d, scr %d, dss %d\n",
+		chip->spi->mode, chip->div_cpsr, chip->div_scr, chip->dss);
+	dev_dbg(&espi->pdev->dev, "setup: cr0 %#x", cr0);
+
+	ep93xx_spi_write_u8(espi, SSPCPSR, chip->div_cpsr);
+	ep93xx_spi_write_u16(espi, SSPCR0, cr0);
+}
+
+static inline int bits_per_word(const struct ep93xx_spi *espi)
+{
+	struct spi_message *msg = espi->current_msg;
+	struct spi_transfer *t = msg->state;
+
+	return t->bits_per_word ? t->bits_per_word : msg->spi->bits_per_word;
+}
+
+static void ep93xx_do_write(struct ep93xx_spi *espi, struct spi_transfer *t)
+{
+	if (bits_per_word(espi) > 8) {
+		u16 tx_val = 0;
+
+		if (t->tx_buf)
+			tx_val = ((u16 *)t->tx_buf)[espi->tx];
+		ep93xx_spi_write_u16(espi, SSPDR, tx_val);
+		espi->tx += sizeof(tx_val);
+	} else {
+		u8 tx_val = 0;
+
+		if (t->tx_buf)
+			tx_val = ((u8 *)t->tx_buf)[espi->tx];
+		ep93xx_spi_write_u8(espi, SSPDR, tx_val);
+		espi->tx += sizeof(tx_val);
+	}
+}
+
+static void ep93xx_do_read(struct ep93xx_spi *espi, struct spi_transfer *t)
+{
+	if (bits_per_word(espi) > 8) {
+		u16 rx_val;
+
+		rx_val = ep93xx_spi_read_u16(espi, SSPDR);
+		if (t->rx_buf)
+			((u16 *)t->rx_buf)[espi->rx] = rx_val;
+		espi->rx += sizeof(rx_val);
+	} else {
+		u8 rx_val;
+
+		rx_val = ep93xx_spi_read_u8(espi, SSPDR);
+		if (t->rx_buf)
+			((u8 *)t->rx_buf)[espi->rx] = rx_val;
+		espi->rx += sizeof(rx_val);
+	}
+}
+
+/**
+ * ep93xx_spi_read_write() - perform next RX/TX transfer
+ * @espi: ep93xx SPI controller struct
+ *
+ * This function transfers next bytes (or half-words) to/from RX/TX FIFOs. If
+ * called several times, the whole transfer will be completed. Returns
+ * %-EINPROGRESS when current transfer was not yet completed otherwise %0.
+ *
+ * When this function is finished, RX FIFO should be empty and TX FIFO should be
+ * full.
+ */
+static int ep93xx_spi_read_write(struct ep93xx_spi *espi)
+{
+	struct spi_message *msg = espi->current_msg;
+	struct spi_transfer *t = msg->state;
+
+	/* read as long as RX FIFO has frames in it */
+	while ((ep93xx_spi_read_u8(espi, SSPSR) & SSPSR_RNE)) {
+		ep93xx_do_read(espi, t);
+		espi->fifo_level--;
+	}
+
+	/* write as long as TX FIFO has room */
+	while (espi->fifo_level < SPI_FIFO_SIZE && espi->tx < t->len) {
+		ep93xx_do_write(espi, t);
+		espi->fifo_level++;
+	}
+
+	if (espi->rx == t->len) {
+		msg->actual_length += t->len;
+		return 0;
+	}
+
+	return -EINPROGRESS;
+}
+
+/**
+ * ep93xx_spi_process_transfer() - processes one SPI transfer
+ * @espi: ep93xx SPI controller struct
+ * @msg: current message
+ * @t: transfer to process
+ *
+ * This function processes one SPI transfer given in @t. Function waits until
+ * transfer is complete (may sleep) and updates @msg->status based on whether
+ * transfer was succesfully processed or not.
+ */
+static void ep93xx_spi_process_transfer(struct ep93xx_spi *espi,
+					struct spi_message *msg,
+					struct spi_transfer *t)
+{
+	struct ep93xx_spi_chip *chip = spi_get_ctldata(msg->spi);
+
+	msg->state = t;
+
+	/*
+	 * Handle any transfer specific settings if needed. We use
+	 * temporary chip settings here and restore original later when
+	 * the transfer is finished.
+	 */
+	if (t->speed_hz || t->bits_per_word) {
+		struct ep93xx_spi_chip tmp_chip = *chip;
+
+		if (t->speed_hz) {
+			int err;
+
+			err = ep93xx_spi_calc_divisors(espi, &tmp_chip,
+						       t->speed_hz);
+			if (err) {
+				dev_err(&espi->pdev->dev,
+					"failed to adjust speed\n");
+				msg->status = err;
+				return;
+			}
+		}
+
+		if (t->bits_per_word)
+			tmp_chip.dss = bits_per_word_to_dss(t->bits_per_word);
+
+		/*
+		 * Set up temporary new hw settings for this transfer.
+		 */
+		ep93xx_spi_chip_setup(espi, &tmp_chip);
+	}
+
+	espi->rx = 0;
+	espi->tx = 0;
+
+	/*
+	 * Now everything is set up for the current transfer. We prime the TX
+	 * FIFO, enable interrupts, and wait for the transfer to complete.
+	 */
+	if (ep93xx_spi_read_write(espi)) {
+		ep93xx_spi_enable_interrupts(espi);
+		wait_for_completion(&espi->wait);
+	}
+
+	/*
+	 * In case of error during transmit, we bail out from processing
+	 * the message.
+	 */
+	if (msg->status)
+		return;
+
+	/*
+	 * After this transfer is finished, perform any possible
+	 * post-transfer actions requested by the protocol driver.
+	 */
+	if (t->delay_usecs) {
+		set_current_state(TASK_UNINTERRUPTIBLE);
+		schedule_timeout(usecs_to_jiffies(t->delay_usecs));
+	}
+	if (t->cs_change) {
+		if (!list_is_last(&t->transfer_list, &msg->transfers)) {
+			/*
+			 * In case protocol driver is asking us to drop the
+			 * chipselect briefly, we let the scheduler to handle
+			 * any "delay" here.
+			 */
+			ep93xx_spi_cs_control(msg->spi, false);
+			cond_resched();
+			ep93xx_spi_cs_control(msg->spi, true);
+		}
+	}
+
+	if (t->speed_hz || t->bits_per_word)
+		ep93xx_spi_chip_setup(espi, chip);
+}
+
+/*
+ * ep93xx_spi_process_message() - process one SPI message
+ * @espi: ep93xx SPI controller struct
+ * @msg: message to process
+ *
+ * This function processes a single SPI message. We go through all transfers in
+ * the message and pass them to ep93xx_spi_process_transfer(). Chipselect is
+ * asserted during the whole message (unless per transfer cs_change is set).
+ *
+ * @msg->status contains %0 in case of success or negative error code in case of
+ * failure.
+ */
+static void ep93xx_spi_process_message(struct ep93xx_spi *espi,
+				       struct spi_message *msg)
+{
+	unsigned long timeout;
+	struct spi_transfer *t;
+	int err;
+
+	/*
+	 * Enable the SPI controller and its clock.
+	 */
+	err = ep93xx_spi_enable(espi);
+	if (err) {
+		dev_err(&espi->pdev->dev, "failed to enable SPI controller\n");
+		msg->status = err;
+		return;
+	}
+
+	/*
+	 * Just to be sure: flush any data from RX FIFO.
+	 */
+	timeout = jiffies + msecs_to_jiffies(SPI_TIMEOUT);
+	while (ep93xx_spi_read_u16(espi, SSPSR) & SSPSR_RNE) {
+		if (time_after(jiffies, timeout)) {
+			dev_warn(&espi->pdev->dev,
+				 "timeout while flushing RX FIFO\n");
+			msg->status = -ETIMEDOUT;
+			return;
+		}
+		ep93xx_spi_read_u16(espi, SSPDR);
+	}
+
+	/*
+	 * We explicitly handle FIFO level. This way we don't have to check TX
+	 * FIFO status using %SSPSR_TNF bit which may cause RX FIFO overruns.
+	 */
+	espi->fifo_level = 0;
+
+	/*
+	 * Update SPI controller registers according to spi device and assert
+	 * the chipselect.
+	 */
+	ep93xx_spi_chip_setup(espi, spi_get_ctldata(msg->spi));
+	ep93xx_spi_cs_control(msg->spi, true);
+
+	list_for_each_entry(t, &msg->transfers, transfer_list) {
+		ep93xx_spi_process_transfer(espi, msg, t);
+		if (msg->status)
+			break;
+	}
+
+	/*
+	 * Now the whole message is transferred (or failed for some reason). We
+	 * deselect the device and disable the SPI controller.
+	 */
+	ep93xx_spi_cs_control(msg->spi, false);
+	ep93xx_spi_disable(espi);
+}
+
+#define work_to_espi(work) (container_of((work), struct ep93xx_spi, msg_work))
+
+/**
+ * ep93xx_spi_work() - EP93xx SPI workqueue worker function
+ * @work: work struct
+ *
+ * Workqueue worker function. This function is called when there are new
+ * SPI messages to be processed. Message is taken out from the queue and then
+ * passed to ep93xx_spi_process_message().
+ *
+ * After message is transferred, protocol driver is notified by calling
+ * @msg->complete(). In case of error, @msg->status is set to negative error
+ * number, otherwise it contains zero (and @msg->actual_length is updated).
+ */
+static void ep93xx_spi_work(struct work_struct *work)
+{
+	struct ep93xx_spi *espi = work_to_espi(work);
+	struct spi_message *msg;
+
+	spin_lock_irq(&espi->lock);
+	if (!espi->running || espi->current_msg ||
+		list_empty(&espi->msg_queue)) {
+		spin_unlock_irq(&espi->lock);
+		return;
+	}
+	msg = list_first_entry(&espi->msg_queue, struct spi_message, queue);
+	list_del_init(&msg->queue);
+	espi->current_msg = msg;
+	spin_unlock_irq(&espi->lock);
+
+	ep93xx_spi_process_message(espi, msg);
+
+	/*
+	 * Update the current message and re-schedule ourselves if there are
+	 * more messages in the queue.
+	 */
+	spin_lock_irq(&espi->lock);
+	espi->current_msg = NULL;
+	if (espi->running && !list_empty(&espi->msg_queue))
+		queue_work(espi->wq, &espi->msg_work);
+	spin_unlock_irq(&espi->lock);
+
+	/* notify the protocol driver that we are done with this message */
+	msg->complete(msg->context);
+}
+
+static irqreturn_t ep93xx_spi_interrupt(int irq, void *dev_id)
+{
+	struct ep93xx_spi *espi = dev_id;
+	u8 irq_status = ep93xx_spi_read_u8(espi, SSPIIR);
+
+	/*
+	 * If we got ROR (receive overrun) interrupt we know that something is
+	 * wrong. Just abort the message.
+	 */
+	if (unlikely(irq_status & SSPIIR_RORIS)) {
+		/* clear the overrun interrupt */
+		ep93xx_spi_write_u8(espi, SSPICR, 0);
+		dev_warn(&espi->pdev->dev,
+			 "receive overrun, aborting the message\n");
+		espi->current_msg->status = -EIO;
+	} else {
+		/*
+		 * Interrupt is either RX (RIS) or TX (TIS). For both cases we
+		 * simply execute next data transfer.
+		 */
+		if (ep93xx_spi_read_write(espi)) {
+			/*
+			 * In normal case, there still is some processing left
+			 * for current transfer. Let's wait for the next
+			 * interrupt then.
+			 */
+			return IRQ_HANDLED;
+		}
+	}
+
+	/*
+	 * Current transfer is finished, either with error or with success. In
+	 * any case we disable interrupts and notify the worker to handle
+	 * any post-processing of the message.
+	 */
+	ep93xx_spi_disable_interrupts(espi);
+	complete(&espi->wait);
+	return IRQ_HANDLED;
+}
+
+static int __init ep93xx_spi_probe(struct platform_device *pdev)
+{
+	struct spi_master *master;
+	struct ep93xx_spi_info *info;
+	struct ep93xx_spi *espi;
+	struct resource *res;
+	int error;
+
+	info = pdev->dev.platform_data;
+
+	master = spi_alloc_master(&pdev->dev, sizeof(*espi));
+	if (!master) {
+		dev_err(&pdev->dev, "failed to allocate spi master\n");
+		return -ENOMEM;
+	}
+
+	master->setup = ep93xx_spi_setup;
+	master->transfer = ep93xx_spi_transfer;
+	master->cleanup = ep93xx_spi_cleanup;
+	master->bus_num = pdev->id;
+	master->num_chipselect = info->num_chipselect;
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
+
+	platform_set_drvdata(pdev, master);
+
+	espi = spi_master_get_devdata(master);
+
+	espi->clk = clk_get(&pdev->dev, NULL);
+	if (IS_ERR(espi->clk)) {
+		dev_err(&pdev->dev, "unable to get spi clock\n");
+		error = PTR_ERR(espi->clk);
+		goto fail_release_master;
+	}
+
+	spin_lock_init(&espi->lock);
+	init_completion(&espi->wait);
+
+	/*
+	 * Calculate maximum and minimum supported clock rates
+	 * for the controller.
+	 */
+	espi->max_rate = clk_get_rate(espi->clk) / 2;
+	espi->min_rate = clk_get_rate(espi->clk) / (254 * 256);
+	espi->pdev = pdev;
+
+	espi->irq = platform_get_irq(pdev, 0);
+	if (espi->irq < 0) {
+		error = -EBUSY;
+		dev_err(&pdev->dev, "failed to get irq resources\n");
+		goto fail_put_clock;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "unable to get iomem resource\n");
+		error = -ENODEV;
+		goto fail_put_clock;
+	}
+
+	res = request_mem_region(res->start, resource_size(res), pdev->name);
+	if (!res) {
+		dev_err(&pdev->dev, "unable to request iomem resources\n");
+		error = -EBUSY;
+		goto fail_put_clock;
+	}
+
+	espi->regs_base = ioremap(res->start, resource_size(res));
+	if (!espi->regs_base) {
+		dev_err(&pdev->dev, "failed to map resources\n");
+		error = -ENODEV;
+		goto fail_free_mem;
+	}
+
+	error = request_irq(espi->irq, ep93xx_spi_interrupt, 0,
+			    "ep93xx-spi", espi);
+	if (error) {
+		dev_err(&pdev->dev, "failed to request irq\n");
+		goto fail_unmap_regs;
+	}
+
+	espi->wq = create_singlethread_workqueue("ep93xx_spid");
+	if (!espi->wq) {
+		dev_err(&pdev->dev, "unable to create workqueue\n");
+		goto fail_free_irq;
+	}
+	INIT_WORK(&espi->msg_work, ep93xx_spi_work);
+	INIT_LIST_HEAD(&espi->msg_queue);
+	espi->running = true;
+
+	/* make sure that the hardware is disabled */
+	ep93xx_spi_write_u8(espi, SSPCR1, 0);
+
+	error = spi_register_master(master);
+	if (error) {
+		dev_err(&pdev->dev, "failed to register SPI master\n");
+		goto fail_free_queue;
+	}
+
+	dev_info(&pdev->dev, "EP93xx SPI Controller at 0x%08lx irq %d\n",
+		 (unsigned long)res->start, espi->irq);
+
+	return 0;
+
+fail_free_queue:
+	destroy_workqueue(espi->wq);
+fail_free_irq:
+	free_irq(espi->irq, espi);
+fail_unmap_regs:
+	iounmap(espi->regs_base);
+fail_free_mem:
+	release_mem_region(res->start, resource_size(res));
+fail_put_clock:
+	clk_put(espi->clk);
+fail_release_master:
+	spi_master_put(master);
+	platform_set_drvdata(pdev, NULL);
+
+	return error;
+}
+
+static int __exit ep93xx_spi_remove(struct platform_device *pdev)
+{
+	struct spi_master *master = platform_get_drvdata(pdev);
+	struct ep93xx_spi *espi = spi_master_get_devdata(master);
+	struct resource *res;
+
+	spin_lock_irq(&espi->lock);
+	espi->running = false;
+	spin_unlock_irq(&espi->lock);
+
+	destroy_workqueue(espi->wq);
+
+	/*
+	 * Complete remaining messages with %-ESHUTDOWN status.
+	 */
+	spin_lock_irq(&espi->lock);
+	while (!list_empty(&espi->msg_queue)) {
+		struct spi_message *msg;
+
+		msg = list_first_entry(&espi->msg_queue,
+				       struct spi_message, queue);
+		list_del_init(&msg->queue);
+		msg->status = -ESHUTDOWN;
+		spin_unlock_irq(&espi->lock);
+		msg->complete(msg->context);
+		spin_lock_irq(&espi->lock);
+	}
+	spin_unlock_irq(&espi->lock);
+
+	free_irq(espi->irq, espi);
+	iounmap(espi->regs_base);
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	release_mem_region(res->start, resource_size(res));
+	clk_put(espi->clk);
+	platform_set_drvdata(pdev, NULL);
+
+	spi_unregister_master(master);
+	return 0;
+}
+
+static struct platform_driver ep93xx_spi_driver = {
+	.driver		= {
+		.name	= "ep93xx-spi",
+		.owner	= THIS_MODULE,
+	},
+	.remove		= __exit_p(ep93xx_spi_remove),
+};
+
+static int __init ep93xx_spi_init(void)
+{
+	return platform_driver_probe(&ep93xx_spi_driver, ep93xx_spi_probe);
+}
+module_init(ep93xx_spi_init);
+
+static void __exit ep93xx_spi_exit(void)
+{
+	platform_driver_unregister(&ep93xx_spi_driver);
+}
+module_exit(ep93xx_spi_exit);
+
+MODULE_DESCRIPTION("EP93xx SPI Controller driver");
+MODULE_AUTHOR("Mika Westerberg <mika.westerberg@iki.fi>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:ep93xx-spi");
-- 
1.5.6.5

Re: [PATCH v7 1/2] spi: implemented driver for Cirrus EP93xx SPI controller

[Martin Guy]

On 5/6/10, Mika Westerberg <mika.westerberg-X3B1VOXEql0@public.gmane.org> wrote:
> This patch adds an SPI master driver for the Cirrus EP93xx SPI controller found
>  in EP93xx chips.

Hi
   I'm confused by the change in this version of the structure of the
board setup code.
   Can you post example patches for the board definitions of the
ts72xx and maybe also the Sim.One?
   I attach the board setup patches I had working with Sim.One v4, but
no longer see how to register the S1's card detect IRQ (the necessary
and the spi platform data.
   For a definitive Sim.One board definition I'll need to hear whether
they wish to assign a GPIO for the chip select (and which) in the next
board revision.

Thanks

     M

------------------------------------------------------------------------------

[PATCH v7 1/2] spi: implemented driver for Cirrus EP93xx SPI controller

[Martin Guy]

On 5/6/10, Mika Westerberg <mika.westerberg@iki.fi> wrote:
> This patch adds an SPI master driver for the Cirrus EP93xx SPI controller found
>  in EP93xx chips.

Hi
   I'm confused by the change in this version of the structure of the
board setup code.
   Can you post example patches for the board definitions of the
ts72xx and maybe also the Sim.One?
   I attach the board setup patches I had working with Sim.One v4, but
no longer see how to register the S1's card detect IRQ (the necessary
and the spi platform data.
   For a definitive Sim.One board definition I'll need to hear whether
they wish to assign a GPIO for the chip select (and which) in the next
board revision.

Thanks

     M

Re: [PATCH v7 1/2] spi: implemented driver for Cirrus EP93xx SPI controller

[Martin Guy]

[-- Attachment #1: Type: text/plain, Size: 156 bytes --]

On 5/8/10, Martin Guy <martinwguy-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>    I attach the board setup patches I had working with Sim.One v4

   M

[-- Attachment #2: Type: text/plain, Size: 80 bytes --]

------------------------------------------------------------------------------


[-- Attachment #3: Type: text/plain, Size: 210 bytes --]

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[PATCH v7 1/2] spi: implemented driver for Cirrus EP93xx SPI controller

[Martin Guy]

On 5/8/10, Martin Guy <martinwguy@gmail.com> wrote:
>    I attach the board setup patches I had working with Sim.One v4

   M
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Re: [PATCH v7 1/2] spi: implemented driver for Cirrus EP93xx SPI controller

[Mika Westerberg]

On Sat, May 08, 2010 at 06:32:47PM +0100, Martin Guy wrote:
> On 5/6/10, Mika Westerberg <mika.westerberg-X3B1VOXEql0@public.gmane.org> wrote:
> > This patch adds an SPI master driver for the Cirrus EP93xx SPI controller found
> >  in EP93xx chips.
> 
>    I'm confused by the change in this version of the structure of the
> board setup code.

Yeah. We changed it to support also other than built-in GPIOs.

>    Can you post example patches for the board definitions of the
> ts72xx and maybe also the Sim.One?

Sample code for TS-7260 can be found Documentation/spi/ep93xx_spi
(which comes with the first patch).

For Sim.One, I modified your patches a bit and resulting patch is
included. Note that I have hooked EGPIO9 as a chip select but in
normal case (SFRMOUT) you can just do following (leave .controller_data
as NULL):

static struct spi_board_info simone_spi_devices[] __initdata = {
	{
		.modalias		= "mmc_spi",
		.platform_data		= &simone_mmc_spi_data,
		/*
		* We use 10 MHz even though the maximum is 3.7 MHz. The driver
		* will limit it automatically to max. frequency.
		*/
		.max_speed_hz		= 10 * 1000 * 1000,
		.bus_num		= 0,
		.chip_select		= 0,
		.mode			= SPI_MODE_0,
	},
};

Regards,
MW

>From 04034329d0442b4a4b30f83fa0bdbd28cf65362f Mon Sep 17 00:00:00 2001
From: Mika Westerberg <mika.westerberg-X3B1VOXEql0@public.gmane.org>
Date: Wed, 28 Apr 2010 08:42:46 +0300
Subject: [PATCH] ep93xx: simone: added board specific SPI support for MMC/SD cards

This includes setting up EGPIOs 0 and 9 for card detection and chip select
respectively.

Signed-off-by: Mika Westerberg <mika.westerberg-X3B1VOXEql0@public.gmane.org>
---
 arch/arm/mach-ep93xx/simone.c |  126 +++++++++++++++++++++++++++++++++++++++++
 1 files changed, 126 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mach-ep93xx/simone.c b/arch/arm/mach-ep93xx/simone.c
index cd93990..b102150 100644
--- a/arch/arm/mach-ep93xx/simone.c
+++ b/arch/arm/mach-ep93xx/simone.c
@@ -18,13 +18,17 @@
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/platform_device.h>
+#include <linux/mmc/host.h>
 #include <linux/mtd/physmap.h>
 #include <linux/gpio.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/mmc_spi.h>
 #include <linux/i2c.h>
 #include <linux/i2c-gpio.h>
 
 #include <mach/hardware.h>
 #include <mach/fb.h>
+#include <mach/ep93xx_spi.h>
 
 #include <asm/mach-types.h>
 #include <asm/mach/arch.h>
@@ -59,6 +63,126 @@ static struct ep93xxfb_mach_info simone_fb_info = {
 	.flags		= EP93XXFB_USE_SDCSN0 | EP93XXFB_PCLK_FALLING,
 };
 
+/*
+ * GPIO lines used for MMC chip select and card detection.
+ */
+#define MMC_CARD_DETECT_GPIO EP93XX_GPIO_LINE_EGPIO0
+#define MMC_CHIP_SELECT_GPIO EP93XX_GPIO_LINE_EGPIO9
+
+/*
+ * MMC SPI chip select GPIO handling. If you are using SFRMOUT (SFRM1) signal,
+ * you can leave these empty and pass NULL as .controller_data.
+ */
+
+static int simone_mmc_spi_setup(struct spi_device *spi)
+{
+	unsigned int gpio = MMC_CHIP_SELECT_GPIO;
+	int err;
+
+	err = gpio_request(gpio, spi->modalias);
+	if (err)
+		return err;
+
+	err = gpio_direction_output(gpio, 1);
+	if (err) {
+		gpio_free(gpio);
+		return err;
+	}
+
+	return 0;
+}
+
+static void simone_mmc_spi_cleanup(struct spi_device *spi)
+{
+	unsigned int gpio = MMC_CHIP_SELECT_GPIO;
+
+	gpio_set_value(gpio, 1);
+	gpio_direction_input(gpio);
+	gpio_free(gpio);
+}
+
+static void simone_mmc_spi_cs_control(struct spi_device *spi, int value)
+{
+	gpio_set_value(MMC_CHIP_SELECT_GPIO, value);
+}
+
+static struct ep93xx_spi_chip_ops simone_mmc_spi_ops = {
+	.setup		= simone_mmc_spi_setup,
+	.cleanup	= simone_mmc_spi_cleanup,
+	.cs_control	= simone_mmc_spi_cs_control,
+};
+
+/*
+ * MMC card detection GPIO setup.
+ */
+
+static int simone_mmc_spi_init(struct device *dev,
+	irqreturn_t (*irq_handler)(int, void *), void *mmc)
+{
+	unsigned int gpio = MMC_CARD_DETECT_GPIO;
+	int irq, err;
+
+	err = gpio_request(gpio, dev_name(dev));
+	if (err)
+		return err;
+
+	err = gpio_direction_input(gpio);
+	if (err)
+		goto fail;
+
+	irq = gpio_to_irq(gpio);
+	if (irq < 0)
+		goto fail;
+
+	err = request_irq(irq, irq_handler, IRQF_TRIGGER_FALLING,
+			  "MMC card detect", mmc);
+	if (err)
+		goto fail;
+
+	printk(KERN_INFO "%s: using irq %d for MMC card detection\n",
+	       dev_name(dev), irq);
+
+	return 0;
+fail:
+	gpio_free(gpio);
+	return err;
+}
+
+static void simone_mmc_spi_exit(struct device *dev, void *mmc)
+{
+	unsigned int gpio = MMC_CARD_DETECT_GPIO;
+
+	free_irq(gpio_to_irq(gpio), mmc);
+	gpio_free(gpio);
+}
+
+static struct mmc_spi_platform_data simone_mmc_spi_data = {
+	.init		= simone_mmc_spi_init,
+	.exit		= simone_mmc_spi_exit,
+	.detect_delay	= 500,
+	.ocr_mask	= MMC_VDD_32_33 | MMC_VDD_33_34,
+};
+
+static struct spi_board_info simone_spi_devices[] __initdata = {
+	{
+		.modalias		= "mmc_spi",
+		.controller_data	= &simone_mmc_spi_ops,
+		.platform_data		= &simone_mmc_spi_data,
+		/*
+		 * We use 10 MHz even though the maximum is 3.7 MHz. The driver
+		 * will limit it automatically to max. frequency.
+		 */
+		.max_speed_hz		= 10 * 1000 * 1000,
+		.bus_num		= 0,
+		.chip_select		= 0,
+		.mode			= SPI_MODE_0,
+	},
+};
+
+static struct ep93xx_spi_info simone_spi_info __initdata = {
+	.num_chipselect	= ARRAY_SIZE(simone_spi_devices),
+};
+
 static struct i2c_gpio_platform_data simone_i2c_gpio_data = {
 	.sda_pin		= EP93XX_GPIO_LINE_EEDAT,
 	.sda_is_open_drain	= 0,
@@ -83,6 +207,8 @@ static void __init simone_init_machine(void)
 	ep93xx_register_fb(&simone_fb_info);
 	ep93xx_register_i2c(&simone_i2c_gpio_data, simone_i2c_board_info,
 			    ARRAY_SIZE(simone_i2c_board_info));
+	ep93xx_register_spi(&simone_spi_info, simone_spi_devices,
+			    ARRAY_SIZE(simone_spi_devices));
 }
 
 MACHINE_START(SIM_ONE, "Simplemachines Sim.One Board")
-- 
1.5.6.5


------------------------------------------------------------------------------

[PATCH v7 1/2] spi: implemented driver for Cirrus EP93xx SPI controller

[Mika Westerberg]

On Sat, May 08, 2010 at 06:32:47PM +0100, Martin Guy wrote:
> On 5/6/10, Mika Westerberg <mika.westerberg@iki.fi> wrote:
> > This patch adds an SPI master driver for the Cirrus EP93xx SPI controller found
> >  in EP93xx chips.
> 
>    I'm confused by the change in this version of the structure of the
> board setup code.

Yeah. We changed it to support also other than built-in GPIOs.

>    Can you post example patches for the board definitions of the
> ts72xx and maybe also the Sim.One?

Sample code for TS-7260 can be found Documentation/spi/ep93xx_spi
(which comes with the first patch).

For Sim.One, I modified your patches a bit and resulting patch is
included. Note that I have hooked EGPIO9 as a chip select but in
normal case (SFRMOUT) you can just do following (leave .controller_data
as NULL):

static struct spi_board_info simone_spi_devices[] __initdata = {
	{
		.modalias		= "mmc_spi",
		.platform_data		= &simone_mmc_spi_data,
		/*
		* We use 10 MHz even though the maximum is 3.7 MHz. The driver
		* will limit it automatically to max. frequency.
		*/
		.max_speed_hz		= 10 * 1000 * 1000,
		.bus_num		= 0,
		.chip_select		= 0,
		.mode			= SPI_MODE_0,
	},
};

Regards,
MW

>From 04034329d0442b4a4b30f83fa0bdbd28cf65362f Mon Sep 17 00:00:00 2001
From: Mika Westerberg <mika.westerberg@iki.fi>
Date: Wed, 28 Apr 2010 08:42:46 +0300
Subject: [PATCH] ep93xx: simone: added board specific SPI support for MMC/SD cards

This includes setting up EGPIOs 0 and 9 for card detection and chip select
respectively.

Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi>
---
 arch/arm/mach-ep93xx/simone.c |  126 +++++++++++++++++++++++++++++++++++++++++
 1 files changed, 126 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mach-ep93xx/simone.c b/arch/arm/mach-ep93xx/simone.c
index cd93990..b102150 100644
--- a/arch/arm/mach-ep93xx/simone.c
+++ b/arch/arm/mach-ep93xx/simone.c
@@ -18,13 +18,17 @@
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/platform_device.h>
+#include <linux/mmc/host.h>
 #include <linux/mtd/physmap.h>
 #include <linux/gpio.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/mmc_spi.h>
 #include <linux/i2c.h>
 #include <linux/i2c-gpio.h>
 
 #include <mach/hardware.h>
 #include <mach/fb.h>
+#include <mach/ep93xx_spi.h>
 
 #include <asm/mach-types.h>
 #include <asm/mach/arch.h>
@@ -59,6 +63,126 @@ static struct ep93xxfb_mach_info simone_fb_info = {
 	.flags		= EP93XXFB_USE_SDCSN0 | EP93XXFB_PCLK_FALLING,
 };
 
+/*
+ * GPIO lines used for MMC chip select and card detection.
+ */
+#define MMC_CARD_DETECT_GPIO EP93XX_GPIO_LINE_EGPIO0
+#define MMC_CHIP_SELECT_GPIO EP93XX_GPIO_LINE_EGPIO9
+
+/*
+ * MMC SPI chip select GPIO handling. If you are using SFRMOUT (SFRM1) signal,
+ * you can leave these empty and pass NULL as .controller_data.
+ */
+
+static int simone_mmc_spi_setup(struct spi_device *spi)
+{
+	unsigned int gpio = MMC_CHIP_SELECT_GPIO;
+	int err;
+
+	err = gpio_request(gpio, spi->modalias);
+	if (err)
+		return err;
+
+	err = gpio_direction_output(gpio, 1);
+	if (err) {
+		gpio_free(gpio);
+		return err;
+	}
+
+	return 0;
+}
+
+static void simone_mmc_spi_cleanup(struct spi_device *spi)
+{
+	unsigned int gpio = MMC_CHIP_SELECT_GPIO;
+
+	gpio_set_value(gpio, 1);
+	gpio_direction_input(gpio);
+	gpio_free(gpio);
+}
+
+static void simone_mmc_spi_cs_control(struct spi_device *spi, int value)
+{
+	gpio_set_value(MMC_CHIP_SELECT_GPIO, value);
+}
+
+static struct ep93xx_spi_chip_ops simone_mmc_spi_ops = {
+	.setup		= simone_mmc_spi_setup,
+	.cleanup	= simone_mmc_spi_cleanup,
+	.cs_control	= simone_mmc_spi_cs_control,
+};
+
+/*
+ * MMC card detection GPIO setup.
+ */
+
+static int simone_mmc_spi_init(struct device *dev,
+	irqreturn_t (*irq_handler)(int, void *), void *mmc)
+{
+	unsigned int gpio = MMC_CARD_DETECT_GPIO;
+	int irq, err;
+
+	err = gpio_request(gpio, dev_name(dev));
+	if (err)
+		return err;
+
+	err = gpio_direction_input(gpio);
+	if (err)
+		goto fail;
+
+	irq = gpio_to_irq(gpio);
+	if (irq < 0)
+		goto fail;
+
+	err = request_irq(irq, irq_handler, IRQF_TRIGGER_FALLING,
+			  "MMC card detect", mmc);
+	if (err)
+		goto fail;
+
+	printk(KERN_INFO "%s: using irq %d for MMC card detection\n",
+	       dev_name(dev), irq);
+
+	return 0;
+fail:
+	gpio_free(gpio);
+	return err;
+}
+
+static void simone_mmc_spi_exit(struct device *dev, void *mmc)
+{
+	unsigned int gpio = MMC_CARD_DETECT_GPIO;
+
+	free_irq(gpio_to_irq(gpio), mmc);
+	gpio_free(gpio);
+}
+
+static struct mmc_spi_platform_data simone_mmc_spi_data = {
+	.init		= simone_mmc_spi_init,
+	.exit		= simone_mmc_spi_exit,
+	.detect_delay	= 500,
+	.ocr_mask	= MMC_VDD_32_33 | MMC_VDD_33_34,
+};
+
+static struct spi_board_info simone_spi_devices[] __initdata = {
+	{
+		.modalias		= "mmc_spi",
+		.controller_data	= &simone_mmc_spi_ops,
+		.platform_data		= &simone_mmc_spi_data,
+		/*
+		 * We use 10 MHz even though the maximum is 3.7 MHz. The driver
+		 * will limit it automatically to max. frequency.
+		 */
+		.max_speed_hz		= 10 * 1000 * 1000,
+		.bus_num		= 0,
+		.chip_select		= 0,
+		.mode			= SPI_MODE_0,
+	},
+};
+
+static struct ep93xx_spi_info simone_spi_info __initdata = {
+	.num_chipselect	= ARRAY_SIZE(simone_spi_devices),
+};
+
 static struct i2c_gpio_platform_data simone_i2c_gpio_data = {
 	.sda_pin		= EP93XX_GPIO_LINE_EEDAT,
 	.sda_is_open_drain	= 0,
@@ -83,6 +207,8 @@ static void __init simone_init_machine(void)
 	ep93xx_register_fb(&simone_fb_info);
 	ep93xx_register_i2c(&simone_i2c_gpio_data, simone_i2c_board_info,
 			    ARRAY_SIZE(simone_i2c_board_info));
+	ep93xx_register_spi(&simone_spi_info, simone_spi_devices,
+			    ARRAY_SIZE(simone_spi_devices));
 }
 
 MACHINE_START(SIM_ONE, "Simplemachines Sim.One Board")
-- 
1.5.6.5

Re: [PATCH v7 1/2] spi: implemented driver for Cirrus EP93xx SPI controller

[Martin Guy]

On 5/9/10, Mika Westerberg <mika.westerberg-X3B1VOXEql0@public.gmane.org> wrote:
> On Sat, May 08, 2010 at 06:32:47PM +0100, Martin Guy wrote:
>  > On 5/6/10, Mika Westerberg <mika.westerberg-X3B1VOXEql0@public.gmane.org> wrote:
>  > > This patch adds an SPI master driver for the Cirrus EP93xx SPI controller found
>  > >  in EP93xx chips.
>
> >    I'm confused by the change in this version of the structure of the
>  > board setup code.
>
>  For Sim.One, I modified your patches a bit and resulting patch is
>  included. Note that I have hooked EGPIO9 as a chip select but in
>  normal case (SFRMOUT) you can just do following (leave .controller_data
>  as NULL):

Many thanks. If you want to submit this to mainline there are just a
couple of changes to make:

> +#define MMC_CHIP_SELECT_GPIO EP93XX_GPIO_LINE_EGPIO9

EGPIO9 is part of the keyboard controller - I don't think we can
hijack that for a patch to the mainline kernel! I've used EGPIO15
which is unused and on TP17 just south of the CPU.

>                 .mode                   = SPI_MODE_0,

Using SPI_MODE_3 increases the read speed from 319 kB/s to 367 kB/s -
even when using a GPIO as the chip select.

Your 4GB card fix works here too, though I'm seeing no difference in
anything between using SFRMOUT and a GPIO for the chip select. Did you
see any functionality or performance improvements using a GPIO for CS
with the SD cards you are testing?

Thanks again

    M

------------------------------------------------------------------------------

[PATCH v7 1/2] spi: implemented driver for Cirrus EP93xx SPI controller

[Martin Guy]

On 5/9/10, Mika Westerberg <mika.westerberg@iki.fi> wrote:
> On Sat, May 08, 2010 at 06:32:47PM +0100, Martin Guy wrote:
>  > On 5/6/10, Mika Westerberg <mika.westerberg@iki.fi> wrote:
>  > > This patch adds an SPI master driver for the Cirrus EP93xx SPI controller found
>  > >  in EP93xx chips.
>
> >    I'm confused by the change in this version of the structure of the
>  > board setup code.
>
>  For Sim.One, I modified your patches a bit and resulting patch is
>  included. Note that I have hooked EGPIO9 as a chip select but in
>  normal case (SFRMOUT) you can just do following (leave .controller_data
>  as NULL):

Many thanks. If you want to submit this to mainline there are just a
couple of changes to make:

> +#define MMC_CHIP_SELECT_GPIO EP93XX_GPIO_LINE_EGPIO9

EGPIO9 is part of the keyboard controller - I don't think we can
hijack that for a patch to the mainline kernel! I've used EGPIO15
which is unused and on TP17 just south of the CPU.

>                 .mode                   = SPI_MODE_0,

Using SPI_MODE_3 increases the read speed from 319 kB/s to 367 kB/s -
even when using a GPIO as the chip select.

Your 4GB card fix works here too, though I'm seeing no difference in
anything between using SFRMOUT and a GPIO for the chip select. Did you
see any functionality or performance improvements using a GPIO for CS
with the SD cards you are testing?

Thanks again

    M

Re: [PATCH v7 1/2] spi: implemented driver for Cirrus EP93xx SPI controller

[Mika Westerberg]

On Sun, May 09, 2010 at 05:47:34PM +0100, Martin Guy wrote:
> On 5/9/10, Mika Westerberg <mika.westerberg-X3B1VOXEql0@public.gmane.org> wrote:
> > On Sat, May 08, 2010 at 06:32:47PM +0100, Martin Guy wrote:
> >  > On 5/6/10, Mika Westerberg <mika.westerberg-X3B1VOXEql0@public.gmane.org> wrote:
> >  > > This patch adds an SPI master driver for the Cirrus EP93xx SPI controller found
> >  > >  in EP93xx chips.
> >
> > >    I'm confused by the change in this version of the structure of the
> >  > board setup code.
> >
> >  For Sim.One, I modified your patches a bit and resulting patch is
> >  included. Note that I have hooked EGPIO9 as a chip select but in
> >  normal case (SFRMOUT) you can just do following (leave .controller_data
> >  as NULL):
> 
> Many thanks. If you want to submit this to mainline there are just a
> couple of changes to make:
> 
> > +#define MMC_CHIP_SELECT_GPIO EP93XX_GPIO_LINE_EGPIO9
> 
> EGPIO9 is part of the keyboard controller - I don't think we can
> hijack that for a patch to the mainline kernel! I've used EGPIO15
> which is unused and on TP17 just south of the CPU.

It was just my own hack ;) Maybe I also use EGPIO15 for the chip select.

I think that we can submit this to mainline only after next Sim.One
revision (is there going to be next one?) where we know what that
GPIO line will be.

> >                 .mode                   = SPI_MODE_0,
> 
> Using SPI_MODE_3 increases the read speed from 319 kB/s to 367 kB/s -
> even when using a GPIO as the chip select.

OK. So we will use MODE_3 in Sim.One (and maybe in TS-7260). Thanks.

> Your 4GB card fix works here too, though I'm seeing no difference in
> anything between using SFRMOUT and a GPIO for the chip select. Did you
> see any functionality or performance improvements using a GPIO for CS
> with the SD cards you are testing?

Actually no. But at least chipselect should work better so I guess
it could help with cards that haven't previously worked.

That 4GB hack is something that need to be further investigated;
It shows that some SDHC cards (at least) will fail when reading
last (Linux) block using multiblock read.

Regards,
MW

------------------------------------------------------------------------------

[PATCH v7 1/2] spi: implemented driver for Cirrus EP93xx SPI controller

[Mika Westerberg]

On Sun, May 09, 2010 at 05:47:34PM +0100, Martin Guy wrote:
> On 5/9/10, Mika Westerberg <mika.westerberg@iki.fi> wrote:
> > On Sat, May 08, 2010 at 06:32:47PM +0100, Martin Guy wrote:
> >  > On 5/6/10, Mika Westerberg <mika.westerberg@iki.fi> wrote:
> >  > > This patch adds an SPI master driver for the Cirrus EP93xx SPI controller found
> >  > >  in EP93xx chips.
> >
> > >    I'm confused by the change in this version of the structure of the
> >  > board setup code.
> >
> >  For Sim.One, I modified your patches a bit and resulting patch is
> >  included. Note that I have hooked EGPIO9 as a chip select but in
> >  normal case (SFRMOUT) you can just do following (leave .controller_data
> >  as NULL):
> 
> Many thanks. If you want to submit this to mainline there are just a
> couple of changes to make:
> 
> > +#define MMC_CHIP_SELECT_GPIO EP93XX_GPIO_LINE_EGPIO9
> 
> EGPIO9 is part of the keyboard controller - I don't think we can
> hijack that for a patch to the mainline kernel! I've used EGPIO15
> which is unused and on TP17 just south of the CPU.

It was just my own hack ;) Maybe I also use EGPIO15 for the chip select.

I think that we can submit this to mainline only after next Sim.One
revision (is there going to be next one?) where we know what that
GPIO line will be.

> >                 .mode                   = SPI_MODE_0,
> 
> Using SPI_MODE_3 increases the read speed from 319 kB/s to 367 kB/s -
> even when using a GPIO as the chip select.

OK. So we will use MODE_3 in Sim.One (and maybe in TS-7260). Thanks.

> Your 4GB card fix works here too, though I'm seeing no difference in
> anything between using SFRMOUT and a GPIO for the chip select. Did you
> see any functionality or performance improvements using a GPIO for CS
> with the SD cards you are testing?

Actually no. But at least chipselect should work better so I guess
it could help with cards that haven't previously worked.

That 4GB hack is something that need to be further investigated;
It shows that some SDHC cards (at least) will fail when reading
last (Linux) block using multiblock read.

Regards,
MW

Re: [PATCH v7 1/2] spi: implemented driver for Cirrus EP93xx SPI controller

[Mika Westerberg]

On Thu, May 06, 2010 at 07:47:04AM +0300, Mika Westerberg wrote:
> This patch adds an SPI master driver for the Cirrus EP93xx SPI controller found
> in EP93xx chips.
> 
> Signed-off-by: Mika Westerberg <mika.westerberg-X3B1VOXEql0@public.gmane.org>
> Signed-off-by: H Hartley Sweeten <hsweeten-3FF4nKcrg1dE2c76skzGb0EOCMrvLtNR@public.gmane.org>
> Acked-by: H Hartley Sweeten <hsweeten-3FF4nKcrg1dE2c76skzGb0EOCMrvLtNR@public.gmane.org>
> Cc: Ryan Mallon <ryan-7Wk5F4Od5/oYd5yxfr4S2w@public.gmane.org>
> Cc: David Brownell <dbrownell-Rn4VEauK+AKRv+LV9MX5uipxlwaOVQ5f@public.gmane.org>
> Cc: Grant Likely <grant.likely-s3s/WqlpOiPyB63q8FvJNQ@public.gmane.org>
> Cc: Martin Guy <martinwguy-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>

Hi Grant,

Ping. Any change getting this driver into .35? Platform side code
is already in linux-next.

Thanks,
MW

------------------------------------------------------------------------------

[PATCH v7 1/2] spi: implemented driver for Cirrus EP93xx SPI controller

[Mika Westerberg]

On Thu, May 06, 2010 at 07:47:04AM +0300, Mika Westerberg wrote:
> This patch adds an SPI master driver for the Cirrus EP93xx SPI controller found
> in EP93xx chips.
> 
> Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi>
> Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
> Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
> Cc: Ryan Mallon <ryan@bluewatersys.com>
> Cc: David Brownell <dbrownell@users.sourceforge.net>
> Cc: Grant Likely <grant.likely@secretlab.ca>
> Cc: Martin Guy <martinwguy@gmail.com>

Hi Grant,

Ping. Any change getting this driver into .35? Platform side code
is already in linux-next.

Thanks,
MW

Re: [PATCH v7 1/2] spi: implemented driver for Cirrus EP93xx SPI controller

[Grant Likely]

On Sat, May 22, 2010 at 1:27 AM, Mika Westerberg <mika.westerberg@iki.fi> wrote:
> On Thu, May 06, 2010 at 07:47:04AM +0300, Mika Westerberg wrote:
>> This patch adds an SPI master driver for the Cirrus EP93xx SPI controller found
>> in EP93xx chips.
>>
>> Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi>
>> Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
>> Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
>> Cc: Ryan Mallon <ryan@bluewatersys.com>
>> Cc: David Brownell <dbrownell@users.sourceforge.net>
>> Cc: Grant Likely <grant.likely@secretlab.ca>
>> Cc: Martin Guy <martinwguy@gmail.com>
>
> Hi Grant,
>
> Ping. Any change getting this driver into .35? Platform side code
> is already in linux-next.

That is my plan.

g.

[PATCH v7 1/2] spi: implemented driver for Cirrus EP93xx SPI controller

[Grant Likely]

On Sat, May 22, 2010 at 1:27 AM, Mika Westerberg <mika.westerberg@iki.fi> wrote:
> On Thu, May 06, 2010 at 07:47:04AM +0300, Mika Westerberg wrote:
>> This patch adds an SPI master driver for the Cirrus EP93xx SPI controller found
>> in EP93xx chips.
>>
>> Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi>
>> Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
>> Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
>> Cc: Ryan Mallon <ryan@bluewatersys.com>
>> Cc: David Brownell <dbrownell@users.sourceforge.net>
>> Cc: Grant Likely <grant.likely@secretlab.ca>
>> Cc: Martin Guy <martinwguy@gmail.com>
>
> Hi Grant,
>
> Ping. Any change getting this driver into .35? Platform side code
> is already in linux-next.

That is my plan.

g.

[PATCH v7 1/2] spi: implemented driver for Cirrus EP93xx SPI controller

[Martin Guy]

On 5/6/10, Mika Westerberg <mika.westerberg@iki.fi> wrote:
> This patch adds an SPI master driver for the Cirrus EP93xx SPI controller found
>  in EP93xx chips.
>
>  Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi>
>  Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
>  Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>

Acked-by: Martin Guy <martinwguy@gmail.com>

[PATCH v7 2/2] ep93xx: SPI driver platform support code

[Mika Westerberg]

This patch adds platform side support code for the EP93xx SPI driver. This
includes clock, resources and muxing. There is a new function: ep93xx_register_spi()
which can be used by board support code to register new SPI devices for the
board.

Signed-off-by: Mika Westerberg <mika.westerberg-X3B1VOXEql0@public.gmane.org>
Acked-by: H Hartley Sweeten <hsweeten-3FF4nKcrg1dE2c76skzGb0EOCMrvLtNR@public.gmane.org>
Cc: Ryan Mallon <ryan-7Wk5F4Od5/oYd5yxfr4S2w@public.gmane.org>
Cc: David Brownell <dbrownell-Rn4VEauK+AKRv+LV9MX5uipxlwaOVQ5f@public.gmane.org>
Cc: Grant Likely <grant.likely-s3s/WqlpOiPyB63q8FvJNQ@public.gmane.org>
Cc: Martin Guy <martinwguy-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
 arch/arm/mach-ep93xx/clock.c                    |   13 ++++++
 arch/arm/mach-ep93xx/core.c                     |   52 +++++++++++++++++++++++
 arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h |    1 +
 arch/arm/mach-ep93xx/include/mach/platform.h    |    4 ++
 4 files changed, 70 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mach-ep93xx/clock.c b/arch/arm/mach-ep93xx/clock.c
index 5f80092..e29bdef 100644
--- a/arch/arm/mach-ep93xx/clock.c
+++ b/arch/arm/mach-ep93xx/clock.c
@@ -96,6 +96,10 @@ static struct clk clk_keypad = {
 	.enable_mask	= EP93XX_SYSCON_KEYTCHCLKDIV_KEN,
 	.set_rate	= set_keytchclk_rate,
 };
+static struct clk clk_spi = {
+	.parent		= &clk_xtali,
+	.rate		= EP93XX_EXT_CLK_RATE,
+};
 static struct clk clk_pwm = {
 	.parent		= &clk_xtali,
 	.rate		= EP93XX_EXT_CLK_RATE,
@@ -186,6 +190,7 @@ static struct clk_lookup clocks[] = {
 	INIT_CK("ep93xx-ohci",		NULL,		&clk_usb_host),
 	INIT_CK("ep93xx-keypad",	NULL,		&clk_keypad),
 	INIT_CK("ep93xx-fb",		NULL,		&clk_video),
+	INIT_CK("ep93xx-spi.0",		NULL,		&clk_spi),
 	INIT_CK(NULL,			"pwm_clk",	&clk_pwm),
 	INIT_CK(NULL,			"m2p0",		&clk_m2p0),
 	INIT_CK(NULL,			"m2p1",		&clk_m2p1),
@@ -473,6 +478,14 @@ static int __init ep93xx_clock_init(void)
 	/* Initialize the pll2 derived clocks */
 	clk_usb_host.rate = clk_pll2.rate / (((value >> 28) & 0xf) + 1);
 
+	/*
+	 * EP93xx SSP clock rate was doubled in version E2. For more information
+	 * see:
+	 *     http://www.cirrus.com/en/pubs/appNote/AN273REV4.pdf
+	 */
+	if (ep93xx_chip_revision() < EP93XX_CHIP_REV_E2)
+		clk_spi.rate /= 2;
+
 	pr_info("PLL1 running at %ld MHz, PLL2 at %ld MHz\n",
 		clk_pll1.rate / 1000000, clk_pll2.rate / 1000000);
 	pr_info("FCLK %ld MHz, HCLK %ld MHz, PCLK %ld MHz\n",
diff --git a/arch/arm/mach-ep93xx/core.c b/arch/arm/mach-ep93xx/core.c
index 90fb591..df2f0a1 100644
--- a/arch/arm/mach-ep93xx/core.c
+++ b/arch/arm/mach-ep93xx/core.c
@@ -31,10 +31,12 @@
 #include <linux/amba/serial.h>
 #include <linux/i2c.h>
 #include <linux/i2c-gpio.h>
+#include <linux/spi/spi.h>
 
 #include <mach/hardware.h>
 #include <mach/fb.h>
 #include <mach/ep93xx_keypad.h>
+#include <mach/ep93xx_spi.h>
 
 #include <asm/mach/map.h>
 #include <asm/mach/time.h>
@@ -398,6 +400,56 @@ void __init ep93xx_register_i2c(struct i2c_gpio_platform_data *data,
 	platform_device_register(&ep93xx_i2c_device);
 }
 
+/*************************************************************************
+ * EP93xx SPI peripheral handling
+ *************************************************************************/
+static struct ep93xx_spi_info ep93xx_spi_master_data;
+
+static struct resource ep93xx_spi_resources[] = {
+	{
+		.start	= EP93XX_SPI_PHYS_BASE,
+		.end	= EP93XX_SPI_PHYS_BASE + 0x18 - 1,
+		.flags	= IORESOURCE_MEM,
+	},
+	{
+		.start	= IRQ_EP93XX_SSP,
+		.end	= IRQ_EP93XX_SSP,
+		.flags	= IORESOURCE_IRQ,
+	},
+};
+
+static struct platform_device ep93xx_spi_device = {
+	.name		= "ep93xx-spi",
+	.id		= 0,
+	.dev		= {
+		.platform_data = &ep93xx_spi_master_data,
+	},
+	.num_resources	= ARRAY_SIZE(ep93xx_spi_resources),
+	.resource	= ep93xx_spi_resources,
+};
+
+/**
+ * ep93xx_register_spi() - registers spi platform device
+ * @info: ep93xx board specific spi master info (__initdata)
+ * @devices: SPI devices to register (__initdata)
+ * @num: number of SPI devices to register
+ *
+ * This function registers platform device for the EP93xx SPI controller and
+ * also makes sure that SPI pins are muxed so that I2S is not using those pins.
+ */
+void __init ep93xx_register_spi(struct ep93xx_spi_info *info,
+				struct spi_board_info *devices, int num)
+{
+	/*
+	 * When SPI is used, we need to make sure that I2S is muxed off from
+	 * SPI pins.
+	 */
+	ep93xx_devcfg_clear_bits(EP93XX_SYSCON_DEVCFG_I2SONSSP);
+
+	ep93xx_spi_master_data = *info;
+	spi_register_board_info(devices, num);
+	platform_device_register(&ep93xx_spi_device);
+}
 
 /*************************************************************************
  * EP93xx LEDs
diff --git a/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h b/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h
index 93e2ecc..b1e096f 100644
--- a/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h
+++ b/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h
@@ -106,6 +106,7 @@
 
 #define EP93XX_AAC_BASE			EP93XX_APB_IOMEM(0x00080000)
 
+#define EP93XX_SPI_PHYS_BASE		EP93XX_APB_PHYS(0x000a0000)
 #define EP93XX_SPI_BASE			EP93XX_APB_IOMEM(0x000a0000)
 
 #define EP93XX_IRDA_BASE		EP93XX_APB_IOMEM(0x000b0000)
diff --git a/arch/arm/mach-ep93xx/include/mach/platform.h b/arch/arm/mach-ep93xx/include/mach/platform.h
index c6dc14d..f11f1d7 100644
--- a/arch/arm/mach-ep93xx/include/mach/platform.h
+++ b/arch/arm/mach-ep93xx/include/mach/platform.h
@@ -6,9 +6,11 @@
 
 struct i2c_gpio_platform_data;
 struct i2c_board_info;
+struct spi_board_info;
 struct platform_device;
 struct ep93xxfb_mach_info;
 struct ep93xx_keypad_platform_data;
+struct ep93xx_spi_info;
 
 struct ep93xx_eth_data
 {
@@ -36,6 +38,8 @@ static inline void ep93xx_devcfg_clear_bits(unsigned int bits)
 void ep93xx_register_eth(struct ep93xx_eth_data *data, int copy_addr);
 void ep93xx_register_i2c(struct i2c_gpio_platform_data *data,
 			 struct i2c_board_info *devices, int num);
+void ep93xx_register_spi(struct ep93xx_spi_info *info,
+			 struct spi_board_info *devices, int num);
 void ep93xx_register_fb(struct ep93xxfb_mach_info *data);
 void ep93xx_register_pwm(int pwm0, int pwm1);
 int ep93xx_pwm_acquire_gpio(struct platform_device *pdev);
-- 
1.5.6.5


------------------------------------------------------------------------------

[PATCH v7 2/2] ep93xx: SPI driver platform support code

[Mika Westerberg]

This patch adds platform side support code for the EP93xx SPI driver. This
includes clock, resources and muxing. There is a new function: ep93xx_register_spi()
which can be used by board support code to register new SPI devices for the
board.

Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ryan Mallon <ryan@bluewatersys.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Martin Guy <martinwguy@gmail.com>
---
 arch/arm/mach-ep93xx/clock.c                    |   13 ++++++
 arch/arm/mach-ep93xx/core.c                     |   52 +++++++++++++++++++++++
 arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h |    1 +
 arch/arm/mach-ep93xx/include/mach/platform.h    |    4 ++
 4 files changed, 70 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mach-ep93xx/clock.c b/arch/arm/mach-ep93xx/clock.c
index 5f80092..e29bdef 100644
--- a/arch/arm/mach-ep93xx/clock.c
+++ b/arch/arm/mach-ep93xx/clock.c
@@ -96,6 +96,10 @@ static struct clk clk_keypad = {
 	.enable_mask	= EP93XX_SYSCON_KEYTCHCLKDIV_KEN,
 	.set_rate	= set_keytchclk_rate,
 };
+static struct clk clk_spi = {
+	.parent		= &clk_xtali,
+	.rate		= EP93XX_EXT_CLK_RATE,
+};
 static struct clk clk_pwm = {
 	.parent		= &clk_xtali,
 	.rate		= EP93XX_EXT_CLK_RATE,
@@ -186,6 +190,7 @@ static struct clk_lookup clocks[] = {
 	INIT_CK("ep93xx-ohci",		NULL,		&clk_usb_host),
 	INIT_CK("ep93xx-keypad",	NULL,		&clk_keypad),
 	INIT_CK("ep93xx-fb",		NULL,		&clk_video),
+	INIT_CK("ep93xx-spi.0",		NULL,		&clk_spi),
 	INIT_CK(NULL,			"pwm_clk",	&clk_pwm),
 	INIT_CK(NULL,			"m2p0",		&clk_m2p0),
 	INIT_CK(NULL,			"m2p1",		&clk_m2p1),
@@ -473,6 +478,14 @@ static int __init ep93xx_clock_init(void)
 	/* Initialize the pll2 derived clocks */
 	clk_usb_host.rate = clk_pll2.rate / (((value >> 28) & 0xf) + 1);
 
+	/*
+	 * EP93xx SSP clock rate was doubled in version E2. For more information
+	 * see:
+	 *     http://www.cirrus.com/en/pubs/appNote/AN273REV4.pdf
+	 */
+	if (ep93xx_chip_revision() < EP93XX_CHIP_REV_E2)
+		clk_spi.rate /= 2;
+
 	pr_info("PLL1 running at %ld MHz, PLL2@%ld MHz\n",
 		clk_pll1.rate / 1000000, clk_pll2.rate / 1000000);
 	pr_info("FCLK %ld MHz, HCLK %ld MHz, PCLK %ld MHz\n",
diff --git a/arch/arm/mach-ep93xx/core.c b/arch/arm/mach-ep93xx/core.c
index 90fb591..df2f0a1 100644
--- a/arch/arm/mach-ep93xx/core.c
+++ b/arch/arm/mach-ep93xx/core.c
@@ -31,10 +31,12 @@
 #include <linux/amba/serial.h>
 #include <linux/i2c.h>
 #include <linux/i2c-gpio.h>
+#include <linux/spi/spi.h>
 
 #include <mach/hardware.h>
 #include <mach/fb.h>
 #include <mach/ep93xx_keypad.h>
+#include <mach/ep93xx_spi.h>
 
 #include <asm/mach/map.h>
 #include <asm/mach/time.h>
@@ -398,6 +400,56 @@ void __init ep93xx_register_i2c(struct i2c_gpio_platform_data *data,
 	platform_device_register(&ep93xx_i2c_device);
 }
 
+/*************************************************************************
+ * EP93xx SPI peripheral handling
+ *************************************************************************/
+static struct ep93xx_spi_info ep93xx_spi_master_data;
+
+static struct resource ep93xx_spi_resources[] = {
+	{
+		.start	= EP93XX_SPI_PHYS_BASE,
+		.end	= EP93XX_SPI_PHYS_BASE + 0x18 - 1,
+		.flags	= IORESOURCE_MEM,
+	},
+	{
+		.start	= IRQ_EP93XX_SSP,
+		.end	= IRQ_EP93XX_SSP,
+		.flags	= IORESOURCE_IRQ,
+	},
+};
+
+static struct platform_device ep93xx_spi_device = {
+	.name		= "ep93xx-spi",
+	.id		= 0,
+	.dev		= {
+		.platform_data = &ep93xx_spi_master_data,
+	},
+	.num_resources	= ARRAY_SIZE(ep93xx_spi_resources),
+	.resource	= ep93xx_spi_resources,
+};
+
+/**
+ * ep93xx_register_spi() - registers spi platform device
+ * @info: ep93xx board specific spi master info (__initdata)
+ * @devices: SPI devices to register (__initdata)
+ * @num: number of SPI devices to register
+ *
+ * This function registers platform device for the EP93xx SPI controller and
+ * also makes sure that SPI pins are muxed so that I2S is not using those pins.
+ */
+void __init ep93xx_register_spi(struct ep93xx_spi_info *info,
+				struct spi_board_info *devices, int num)
+{
+	/*
+	 * When SPI is used, we need to make sure that I2S is muxed off from
+	 * SPI pins.
+	 */
+	ep93xx_devcfg_clear_bits(EP93XX_SYSCON_DEVCFG_I2SONSSP);
+
+	ep93xx_spi_master_data = *info;
+	spi_register_board_info(devices, num);
+	platform_device_register(&ep93xx_spi_device);
+}
 
 /*************************************************************************
  * EP93xx LEDs
diff --git a/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h b/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h
index 93e2ecc..b1e096f 100644
--- a/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h
+++ b/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h
@@ -106,6 +106,7 @@
 
 #define EP93XX_AAC_BASE			EP93XX_APB_IOMEM(0x00080000)
 
+#define EP93XX_SPI_PHYS_BASE		EP93XX_APB_PHYS(0x000a0000)
 #define EP93XX_SPI_BASE			EP93XX_APB_IOMEM(0x000a0000)
 
 #define EP93XX_IRDA_BASE		EP93XX_APB_IOMEM(0x000b0000)
diff --git a/arch/arm/mach-ep93xx/include/mach/platform.h b/arch/arm/mach-ep93xx/include/mach/platform.h
index c6dc14d..f11f1d7 100644
--- a/arch/arm/mach-ep93xx/include/mach/platform.h
+++ b/arch/arm/mach-ep93xx/include/mach/platform.h
@@ -6,9 +6,11 @@
 
 struct i2c_gpio_platform_data;
 struct i2c_board_info;
+struct spi_board_info;
 struct platform_device;
 struct ep93xxfb_mach_info;
 struct ep93xx_keypad_platform_data;
+struct ep93xx_spi_info;
 
 struct ep93xx_eth_data
 {
@@ -36,6 +38,8 @@ static inline void ep93xx_devcfg_clear_bits(unsigned int bits)
 void ep93xx_register_eth(struct ep93xx_eth_data *data, int copy_addr);
 void ep93xx_register_i2c(struct i2c_gpio_platform_data *data,
 			 struct i2c_board_info *devices, int num);
+void ep93xx_register_spi(struct ep93xx_spi_info *info,
+			 struct spi_board_info *devices, int num);
 void ep93xx_register_fb(struct ep93xxfb_mach_info *data);
 void ep93xx_register_pwm(int pwm0, int pwm1);
 int ep93xx_pwm_acquire_gpio(struct platform_device *pdev);
-- 
1.5.6.5

Re: [PATCH v7 2/2] ep93xx: SPI driver platform support code

[Martin Guy]

On 5/6/10, Mika Westerberg <mika.westerberg@iki.fi> wrote:
> This patch adds platform side support code for the EP93xx SPI driver. This
>  includes clock, resources and muxing. There is a new function: ep93xx_register_spi()
>  which can be used by board support code to register new SPI devices for the
>  board.
>
>  Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi>
>  Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>

Acked-by: Martin Guy <martinwguy@gmail.com>

[PATCH v7 2/2] ep93xx: SPI driver platform support code

[Martin Guy]

On 5/6/10, Mika Westerberg <mika.westerberg@iki.fi> wrote:
> This patch adds platform side support code for the EP93xx SPI driver. This
>  includes clock, resources and muxing. There is a new function: ep93xx_register_spi()
>  which can be used by board support code to register new SPI devices for the
>  board.
>
>  Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi>
>  Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>

Acked-by: Martin Guy <martinwguy@gmail.com>