* [PATCH v1 1/3] dt: bindings: add documentation for zx2967 family i2c controller
@ 2017-01-20 8:43 Baoyou Xie
2017-01-20 8:43 ` [PATCH v1 2/3] MAINTAINERS: add zx2967 i2c controller driver to ARM ZTE architecture Baoyou Xie
2017-01-20 8:43 ` [PATCH v1 3/3] i2c: zx2967: add i2c controller driver for ZTE's zx2967 family Baoyou Xie
0 siblings, 2 replies; 5+ messages in thread
From: Baoyou Xie @ 2017-01-20 8:43 UTC (permalink / raw)
To: jun.nie, wsa, robh+dt, mark.rutland
Cc: linux-arm-kernel, linux-i2c, devicetree, linux-kernel, shawnguo,
baoyou.xie, xie.baoyou, chen.chaokai, wang.qiang01
This patch adds dt-binding documentation for zx2967 family
i2c controller.
Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
---
.../devicetree/bindings/i2c/i2c-zx2967.txt | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)
create mode 100644 Documentation/devicetree/bindings/i2c/i2c-zx2967.txt
diff --git a/Documentation/devicetree/bindings/i2c/i2c-zx2967.txt b/Documentation/devicetree/bindings/i2c/i2c-zx2967.txt
new file mode 100644
index 0000000..cb806d1
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-zx2967.txt
@@ -0,0 +1,22 @@
+ZTE zx2967 I2C controller
+
+Required properties:
+ - compatible: must be "zte,zx296718-i2c"
+ - reg: physical address and length of the device registers
+ - interrupts: a single interrupt specifier
+ - clocks: clock for the device
+ - #address-cells: should be <1>
+ - #size-cells: should be <0>
+ - clock-frequency: the desired I2C bus clock frequency.
+
+Examples:
+
+ i2c@112000 {
+ compatible = "zte,zx296718-i2c";
+ reg = <0x00112000 0x1000>;
+ interrupts = <GIC_SPI 112 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&osc24m>;
+ #address-cells = <1>
+ #size-cells = <0>;
+ clock-frequency = <1600000>;
+ };
--
2.7.4
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH v1 2/3] MAINTAINERS: add zx2967 i2c controller driver to ARM ZTE architecture
2017-01-20 8:43 [PATCH v1 1/3] dt: bindings: add documentation for zx2967 family i2c controller Baoyou Xie
@ 2017-01-20 8:43 ` Baoyou Xie
2017-01-20 8:43 ` [PATCH v1 3/3] i2c: zx2967: add i2c controller driver for ZTE's zx2967 family Baoyou Xie
1 sibling, 0 replies; 5+ messages in thread
From: Baoyou Xie @ 2017-01-20 8:43 UTC (permalink / raw)
To: jun.nie, wsa, robh+dt, mark.rutland
Cc: linux-arm-kernel, linux-i2c, devicetree, linux-kernel, shawnguo,
baoyou.xie, xie.baoyou, chen.chaokai, wang.qiang01
Add the zx2967 i2c controller driver as maintained by ARM ZTE
architecture maintainers, as they're parts of the core IP.
Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
---
MAINTAINERS | 2 ++
1 file changed, 2 insertions(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index 275c434..757c098 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1987,12 +1987,14 @@ L: linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
S: Maintained
F: arch/arm/mach-zx/
F: drivers/clk/zte/
+F: drivers/i2c/busses/i2c-zx2967.c
F: drivers/reset/reset-zx2967.c
F: drivers/soc/zte/
F: drivers/thermal/zx*
F: drivers/watchdog/zx2967_wdt.c
F: Documentation/devicetree/bindings/arm/zte.txt
F: Documentation/devicetree/bindings/clock/zx296702-clk.txt
+F: Documentation/devicetree/bindings/i2c/i2c-zx2967.txt
F: Documentation/devicetree/bindings/reset/zte,zx2967-reset.txt
F: Documentation/devicetree/bindings/soc/zte/
F: Documentation/devicetree/bindings/thermal/zx*
--
2.7.4
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH v1 3/3] i2c: zx2967: add i2c controller driver for ZTE's zx2967 family
2017-01-20 8:43 [PATCH v1 1/3] dt: bindings: add documentation for zx2967 family i2c controller Baoyou Xie
2017-01-20 8:43 ` [PATCH v1 2/3] MAINTAINERS: add zx2967 i2c controller driver to ARM ZTE architecture Baoyou Xie
@ 2017-01-20 8:43 ` Baoyou Xie
2017-01-20 21:45 ` Andy Shevchenko
2017-01-23 2:50 ` Shawn Guo
1 sibling, 2 replies; 5+ messages in thread
From: Baoyou Xie @ 2017-01-20 8:43 UTC (permalink / raw)
To: jun.nie, wsa, robh+dt, mark.rutland
Cc: linux-arm-kernel, linux-i2c, devicetree, linux-kernel, shawnguo,
baoyou.xie, xie.baoyou, chen.chaokai, wang.qiang01
This patch adds i2c controller driver for ZTE's zx2967 family.
Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
---
drivers/i2c/busses/Kconfig | 8 +
drivers/i2c/busses/Makefile | 1 +
drivers/i2c/busses/i2c-zx2967.c | 645 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 654 insertions(+)
create mode 100644 drivers/i2c/busses/i2c-zx2967.c
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index e4a603e..946d2b0 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -1246,4 +1246,12 @@ config I2C_OPAL
This driver can also be built as a module. If so, the module will be
called as i2c-opal.
+config I2C_ZX2967
+ bool "ZTE zx2967 I2C support"
+ depends on ARCH_ZX
+ default y
+ help
+ Selecting this option will add ZX I2C driver.
+ If unsure, say y.
+
endmenu
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index beb4809..16b2901 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -101,6 +101,7 @@ obj-$(CONFIG_I2C_XILINX) += i2c-xiic.o
obj-$(CONFIG_I2C_XLR) += i2c-xlr.o
obj-$(CONFIG_I2C_XLP9XX) += i2c-xlp9xx.o
obj-$(CONFIG_I2C_RCAR) += i2c-rcar.o
+obj-$(CONFIG_I2C_ZX2967) += i2c-zx2967.o
# External I2C/SMBus adapter drivers
obj-$(CONFIG_I2C_DIOLAN_U2C) += i2c-diolan-u2c.o
diff --git a/drivers/i2c/busses/i2c-zx2967.c b/drivers/i2c/busses/i2c-zx2967.c
new file mode 100644
index 0000000..6c2145b
--- /dev/null
+++ b/drivers/i2c/busses/i2c-zx2967.c
@@ -0,0 +1,645 @@
+/*
+ * ZTE's zx2967 family i2c bus controller driver
+ *
+ * Copyright (C) 2017 ZTE Ltd.
+ *
+ * Author: Baoyou Xie <baoyou.xie@linaro.org>
+ *
+ * License terms: GNU General Public License (GPL) version 2
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/platform_device.h>
+
+#define BW1 (u32)1
+
+#define REG_CMD 0x04
+#define REG_DEVADDR_H 0x0C
+#define REG_DEVADDR_L 0x10
+#define REG_CLK_DIV_FS 0x14
+#define REG_CLK_DIV_HS 0x18
+#define REG_WRCONF 0x1C
+#define REG_RDCONF 0x20
+#define REG_DATA 0x24
+#define REG_STAT 0x28
+
+#define I2C_STOP 0
+#define I2C_MASTER (1 << 0)
+#define I2C_ADDR_MODE_TEN (1 << 1)
+#define I2C_IRQ_MSK_ENABLE (1 << 3)
+#define I2C_RW_READ (1 << 4)
+#define I2C_CMB_RW_EN (1 << 5)
+#define I2C_START (1 << 6)
+#define I2C_ADDR_MODE_TEN (1 << 1)
+
+#define I2C_WFIFO_RESET (1 << 7)
+#define I2C_RFIFO_RESET (1 << 7)
+
+#define I2C_IRQ_ACK_CLEAR (1 << 7)
+#define I2C_INT_MASK 0x3f
+
+#define I2C_TRANS_DONE (1 << 0)
+#define I2C_ERROR_DEVICE (1 << 1)
+#define I2C_ERROR_DATA (1 << 2)
+#define I2C_ERROR_MASK (I2C_ERROR_DATA | I2C_ERROR_DEVICE)
+
+#define I2C_SR_BUSY (1 << 6)
+
+#define I2C_SR_EDEVICE (1 << 1)
+#define I2C_SR_EDATA (1 << 2)
+
+#define I2C_FIFO_MAX 16
+
+#define I2C_TIMEOUT msecs_to_jiffies(1000)
+
+struct zx2967_i2c_info {
+ spinlock_t lock;
+ struct device *dev;
+ struct i2c_adapter adap;
+ struct clk *clk;
+ struct completion complete;
+ u32 clk_freq;
+ struct pinctrl *pin_scl;
+ struct pinctrl *pin_sda;
+ void __iomem *reg_base;
+ size_t residue;
+ int id;
+ int irq;
+ int msg_rd;
+ u8 *buf;
+ u8 access_cnt;
+ bool is_suspended;
+};
+
+static void zx2967_i2c_writel(struct zx2967_i2c_info *zx_i2c,
+ u32 val, unsigned long reg)
+{
+ writel_relaxed(val, zx_i2c->reg_base + reg);
+}
+
+static u32 zx2967_i2c_readl(struct zx2967_i2c_info *zx_i2c, unsigned long reg)
+{
+ return readl_relaxed(zx_i2c->reg_base + reg);
+}
+
+static void zx2967_i2c_writesb(struct zx2967_i2c_info *zx_i2c,
+ void *data, unsigned long reg, int len)
+{
+ writesb(zx_i2c->reg_base + reg, data, len);
+}
+
+static void zx2967_i2c_readsb(struct zx2967_i2c_info *zx_i2c,
+ void *data, unsigned long reg, int len)
+{
+ readsb(zx_i2c->reg_base + reg, data, len);
+}
+
+static void zx2967_i2c_start_ctrl(struct zx2967_i2c_info *zx_i2c)
+{
+ u32 status;
+ u32 ctl;
+
+ status = zx2967_i2c_readl(zx_i2c, REG_STAT);
+ status |= I2C_IRQ_ACK_CLEAR;
+ zx2967_i2c_writel(zx_i2c, status, REG_STAT);
+
+ ctl = zx2967_i2c_readl(zx_i2c, REG_CMD);
+ if (zx_i2c->msg_rd)
+ ctl |= I2C_RW_READ;
+ else
+ ctl &= ~I2C_RW_READ;
+ ctl &= ~I2C_CMB_RW_EN;
+ ctl |= I2C_START;
+ zx2967_i2c_writel(zx_i2c, ctl, REG_CMD);
+}
+
+static int zx2967_i2c_flush_fifos(struct zx2967_i2c_info *zx_i2c)
+{
+ u32 val = 0;
+ u32 offset = 0;
+
+ if (zx_i2c->msg_rd) {
+ offset = REG_RDCONF;
+ val = I2C_RFIFO_RESET;
+ } else {
+ offset = REG_WRCONF;
+ val = I2C_WFIFO_RESET;
+ }
+
+ val |= zx2967_i2c_readl(zx_i2c, offset);
+ zx2967_i2c_writel(zx_i2c, val, offset);
+
+ return 0;
+}
+
+static int zx2967_i2c_empty_rx_fifo(struct zx2967_i2c_info *zx_i2c, u32 size)
+{
+ u8 val[I2C_FIFO_MAX] = {0};
+ int i = 0;
+
+ if (size == 0) {
+ dev_err(zx_i2c->dev, "size is invalid\n");
+ return -EINVAL;
+ }
+
+ zx2967_i2c_readsb(zx_i2c, val, REG_DATA, size);
+ for (i = 0; i < size; i++) {
+ *(zx_i2c->buf++) = val[i];
+ zx_i2c->residue--;
+ if (zx_i2c->residue <= 0)
+ break;
+ }
+
+ barrier();
+
+ return 0;
+}
+
+static int zx2967_i2c_fill_tx_fifo(struct zx2967_i2c_info *zx_i2c)
+{
+ u8 *buf = zx_i2c->buf;
+ size_t residue = zx_i2c->residue;
+
+ if (residue == 0) {
+ dev_err(zx_i2c->dev, "residue is %d\n", (int)residue);
+ return -EINVAL;
+ }
+
+ if (residue <= I2C_FIFO_MAX) {
+ zx2967_i2c_writesb(zx_i2c, buf, REG_DATA, residue);
+
+ /* Again update before writing to FIFO to make sure isr sees. */
+ zx_i2c->residue = 0;
+ zx_i2c->buf = NULL;
+ } else {
+ zx2967_i2c_writesb(zx_i2c, buf, REG_DATA, I2C_FIFO_MAX);
+ zx_i2c->residue -= I2C_FIFO_MAX;
+ zx_i2c->buf += I2C_FIFO_MAX;
+ }
+
+ barrier();
+
+ return 0;
+}
+
+static int zx2967_i2c_reset_hardware(struct zx2967_i2c_info *zx_i2c)
+{
+ u32 val;
+ u32 clk_div;
+ u32 status;
+
+ val = I2C_MASTER | I2C_IRQ_MSK_ENABLE;
+ zx2967_i2c_writel(zx_i2c, val, REG_CMD);
+
+ clk_div = clk_get_rate(zx_i2c->clk) / zx_i2c->clk_freq - 1;
+ zx2967_i2c_writel(zx_i2c, clk_div, REG_CLK_DIV_FS);
+ zx2967_i2c_writel(zx_i2c, clk_div, REG_CLK_DIV_HS);
+
+ zx2967_i2c_writel(zx_i2c, I2C_FIFO_MAX - 1, REG_WRCONF);
+ zx2967_i2c_writel(zx_i2c, I2C_FIFO_MAX - 1, REG_RDCONF);
+ zx2967_i2c_writel(zx_i2c, 1, REG_RDCONF);
+
+ if (zx2967_i2c_flush_fifos(zx_i2c))
+ return -ETIMEDOUT;
+
+ status = zx2967_i2c_readl(zx_i2c, REG_STAT);
+ if (status & (I2C_SR_BUSY))
+ return -EBUSY;
+ if (status & (I2C_SR_EDEVICE | I2C_SR_EDATA))
+ return -EIO;
+
+ enable_irq(zx_i2c->irq);
+
+ return 0;
+}
+
+static void zx2967_i2c_isr_clr(struct zx2967_i2c_info *zx_i2c)
+{
+ u32 status;
+
+ status = zx2967_i2c_readl(zx_i2c, REG_STAT);
+ status |= I2C_IRQ_ACK_CLEAR;
+ zx2967_i2c_writel(zx_i2c, status, REG_STAT);
+}
+
+static irqreturn_t zx2967_i2c_isr(int irq, void *dev_id)
+{
+ u32 status;
+ struct zx2967_i2c_info *zx_i2c = (struct zx2967_i2c_info *)dev_id;
+ unsigned long flags;
+
+ spin_lock_irqsave(&zx_i2c->lock, flags);
+
+ status = zx2967_i2c_readl(zx_i2c, REG_STAT) & I2C_INT_MASK;
+ zx2967_i2c_isr_clr(zx_i2c);
+
+ if (status & I2C_ERROR_MASK) {
+ spin_unlock_irqrestore(&zx_i2c->lock, flags);
+ return IRQ_HANDLED;
+ }
+
+ if (status & I2C_TRANS_DONE)
+ complete(&zx_i2c->complete);
+
+ spin_unlock_irqrestore(&zx_i2c->lock, flags);
+
+ return IRQ_HANDLED;
+}
+
+static void zx2967_enable_tenbit(struct zx2967_i2c_info *zx_i2c, __u16 addr)
+{
+ u16 val = ((addr >> 7) & 0x7);
+
+ if (val > 0) {
+ zx2967_i2c_writel(zx_i2c, val, REG_DEVADDR_H);
+ val = (zx2967_i2c_readl(zx_i2c, REG_CMD)) | I2C_ADDR_MODE_TEN;
+ zx2967_i2c_writel(zx_i2c, val, REG_CMD);
+ }
+}
+
+static int zx2967_i2c_xfer_msg(struct zx2967_i2c_info *zx_i2c,
+ struct i2c_msg *msg)
+{
+ unsigned long time_left = 0;
+ unsigned int i = 0;
+
+ if (msg->len == 0)
+ return -EINVAL;
+
+ zx2967_i2c_flush_fifos(zx_i2c);
+
+ zx_i2c->buf = msg->buf;
+ zx_i2c->residue = msg->len;
+ zx_i2c->access_cnt = msg->len / I2C_FIFO_MAX;
+ zx_i2c->msg_rd = (msg->flags & I2C_M_RD);
+
+ if (zx_i2c->msg_rd) {
+ for (i = 0; i < zx_i2c->access_cnt; i++) {
+ reinit_completion(&zx_i2c->complete);
+ zx2967_i2c_writel(zx_i2c, I2C_FIFO_MAX - 1,
+ REG_RDCONF);
+ zx2967_i2c_start_ctrl(zx_i2c);
+
+ time_left = wait_for_completion_timeout(
+ &zx_i2c->complete, I2C_TIMEOUT);
+ if (time_left == 0) {
+ dev_err(zx_i2c->dev,
+ "read i2c transfer timed out\n");
+ disable_irq(zx_i2c->irq);
+ zx2967_i2c_reset_hardware(zx_i2c);
+ return -EIO;
+ }
+
+ zx2967_i2c_empty_rx_fifo(zx_i2c, I2C_FIFO_MAX);
+ }
+
+ if (zx_i2c->residue < I2C_FIFO_MAX) {
+ reinit_completion(&zx_i2c->complete);
+ zx2967_i2c_writel(zx_i2c, zx_i2c->residue - 1,
+ REG_RDCONF);
+ zx2967_i2c_start_ctrl(zx_i2c);
+ time_left = wait_for_completion_timeout(
+ &zx_i2c->complete, I2C_TIMEOUT);
+ if (time_left == 0) {
+ dev_err(zx_i2c->dev,
+ "read i2c transfer timed out\n");
+ disable_irq(zx_i2c->irq);
+ zx2967_i2c_reset_hardware(zx_i2c);
+ return -EIO;
+ }
+
+ zx2967_i2c_empty_rx_fifo(zx_i2c, zx_i2c->residue);
+ }
+
+ zx_i2c->residue = 0;
+ zx_i2c->access_cnt = 0;
+ } else {
+ reinit_completion(&zx_i2c->complete);
+ zx2967_i2c_fill_tx_fifo(zx_i2c);
+ zx2967_i2c_start_ctrl(zx_i2c);
+
+ for (i = 0; i < zx_i2c->access_cnt; i++) {
+ time_left = wait_for_completion_timeout(
+ &zx_i2c->complete, I2C_TIMEOUT);
+ if (time_left == 0) {
+ dev_err(zx_i2c->dev,
+ "write i2c transfer timed out\n");
+ disable_irq(zx_i2c->irq);
+ zx2967_i2c_reset_hardware(zx_i2c);
+ return -EIO;
+ }
+
+ if (zx_i2c->residue != 0) {
+ reinit_completion(&zx_i2c->complete);
+ zx2967_i2c_fill_tx_fifo(zx_i2c);
+ zx2967_i2c_start_ctrl(zx_i2c);
+ }
+ }
+ }
+
+ return 0;
+}
+
+static int zx2967_i2c_xfer(struct i2c_adapter *adap,
+ struct i2c_msg *msgs, int num)
+{
+ int i;
+ int ret = 0;
+ struct zx2967_i2c_info *zx_i2c = i2c_get_adapdata(adap);
+
+ if (zx_i2c->is_suspended)
+ return -EBUSY;
+
+ zx2967_i2c_writel(zx_i2c, (msgs->addr & 0x7f), REG_DEVADDR_L);
+ zx2967_i2c_writel(zx_i2c, (msgs->addr >> 7) & 0x7, REG_DEVADDR_H);
+ if (zx2967_i2c_readl(zx_i2c, REG_DEVADDR_H) > 0)
+ zx2967_enable_tenbit(zx_i2c, msgs->addr);
+
+ for (i = 0; i < num; i++) {
+ ret = zx2967_i2c_xfer_msg(zx_i2c, &msgs[i]);
+ if (num > 1)
+ usleep_range(1000, 2000);
+ if (ret)
+ break;
+ }
+
+ return ret ?: i;
+}
+
+static int zx2967_smbus_xfer(struct i2c_adapter *adap, u16 addr,
+ unsigned short flags, char read_write,
+ u8 command, int size, union i2c_smbus_data *data)
+{
+ struct zx2967_i2c_info *zx_i2c = i2c_get_adapdata(adap);
+ u32 val;
+ u8 buf[2];
+ unsigned long time_left;
+
+ val = zx2967_i2c_readl(zx_i2c, REG_RDCONF);
+ val |= I2C_RFIFO_RESET;
+ zx2967_i2c_writel(zx_i2c, val, REG_RDCONF);
+ zx2967_i2c_writel(zx_i2c, (addr & 0x7f), REG_DEVADDR_L);
+
+ zx2967_enable_tenbit(zx_i2c, addr);
+ val = zx2967_i2c_readl(zx_i2c, REG_CMD);
+ val &= ~I2C_RW_READ;
+ zx2967_i2c_writel(zx_i2c, val, REG_CMD);
+
+ switch (size) {
+ case I2C_SMBUS_QUICK:
+ read_write = I2C_SMBUS_WRITE;
+ break;
+ case I2C_SMBUS_BYTE:
+ zx2967_i2c_writel(zx_i2c, command, REG_DATA);
+ break;
+ case I2C_SMBUS_BYTE_DATA:
+ zx2967_i2c_writel(zx_i2c, command, REG_DATA);
+
+ if (read_write == I2C_SMBUS_WRITE)
+ zx2967_i2c_writel(zx_i2c, data->byte, REG_DATA);
+
+ break;
+ case I2C_SMBUS_WORD_DATA:
+ zx2967_i2c_writel(zx_i2c, command, REG_DATA);
+ zx2967_i2c_writel(zx_i2c, (data->word & 0xff), REG_DATA);
+
+ if (read_write == I2C_SMBUS_WRITE) {
+ zx2967_i2c_writel(zx_i2c, (data->word >> 8), REG_DATA);
+ zx2967_i2c_writel(zx_i2c,
+ (data->word & 0xff), REG_DATA);
+ }
+ break;
+
+ default:
+ dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
+ return -EOPNOTSUPP;
+ }
+
+ if (read_write == I2C_SMBUS_WRITE) {
+ reinit_completion(&zx_i2c->complete);
+ val = zx2967_i2c_readl(zx_i2c, REG_CMD);
+ val |= I2C_START;
+ zx2967_i2c_writel(zx_i2c, val, REG_CMD);
+
+ time_left = wait_for_completion_timeout(
+ &zx_i2c->complete, I2C_TIMEOUT);
+ if (time_left == 0) {
+ dev_err(zx_i2c->dev, "i2c write transfer timed out\n");
+ disable_irq(zx_i2c->irq);
+ zx2967_i2c_reset_hardware(zx_i2c);
+ return -EIO;
+ }
+
+ return 0;
+ }
+
+ reinit_completion(&zx_i2c->complete);
+
+ val = zx2967_i2c_readl(zx_i2c, REG_CMD);
+ val |= I2C_CMB_RW_EN;
+ zx2967_i2c_writel(zx_i2c, val, REG_CMD);
+
+ val = zx2967_i2c_readl(zx_i2c, REG_CMD);
+ val |= I2C_START;
+ zx2967_i2c_writel(zx_i2c, val, REG_CMD);
+
+ time_left = wait_for_completion_timeout(&zx_i2c->complete,
+ I2C_TIMEOUT);
+ if (time_left == 0) {
+ dev_err(zx_i2c->dev, "i2c read transfer timed out\n");
+ disable_irq(zx_i2c->irq);
+ zx2967_i2c_reset_hardware(zx_i2c);
+ return -EIO;
+ }
+
+ usleep_range(1000, 2000);
+ switch (size) {
+ case I2C_SMBUS_BYTE:
+ case I2C_SMBUS_BYTE_DATA:
+ val = zx2967_i2c_readl(zx_i2c, REG_DATA);
+ data->byte = val;
+ break;
+ case I2C_SMBUS_WORD_DATA:
+ case I2C_SMBUS_PROC_CALL:
+ buf[0] = zx2967_i2c_readl(zx_i2c, REG_DATA);
+ buf[1] = zx2967_i2c_readl(zx_i2c, REG_DATA);
+ data->word = (buf[0] << 8) | buf[1];
+ break;
+ default:
+ dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
+ return -EOPNOTSUPP;
+ }
+
+ return 0;
+}
+
+static u32 zx2967_i2c_func(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
+ I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
+ I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_PROC_CALL |
+ I2C_FUNC_I2C | I2C_FUNC_SMBUS_I2C_BLOCK;
+}
+
+#ifdef CONFIG_PM
+static int zx2967_i2c_suspend(struct device *dev)
+{
+ struct zx2967_i2c_info *zx_i2c = dev_get_drvdata(dev);
+
+ zx_i2c->is_suspended = true;
+ if (__clk_get_enable_count(zx_i2c->clk) == 1)
+ clk_disable_unprepare(zx_i2c->clk);
+
+ return 0;
+}
+
+static int zx2967_i2c_resume(struct device *dev)
+{
+ struct zx2967_i2c_info *zx_i2c = dev_get_drvdata(dev);
+
+ zx_i2c->is_suspended = false;
+ clk_prepare_enable(zx_i2c->clk);
+
+ return 0;
+}
+static const struct dev_pm_ops zx2967_i2c_dev_pm_ops = {
+ .suspend = zx2967_i2c_suspend,
+ .resume = zx2967_i2c_resume,
+};
+#define ZX2967_I2C_DEV_PM_OPS (&zx2967_i2c_dev_pm_ops)
+#else
+#define ZX2967_I2C_DEV_PM_OPS NULL
+#endif
+
+static const struct i2c_algorithm zx2967_i2c_algo = {
+ .master_xfer = zx2967_i2c_xfer,
+ .smbus_xfer = zx2967_smbus_xfer,
+ .functionality = zx2967_i2c_func,
+};
+
+static const struct of_device_id zx2967_i2c_of_match[] = {
+ { .compatible = "zte,zx296718-i2c", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, zx2967_i2c_of_match);
+
+static int zx2967_i2c_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ struct zx2967_i2c_info *zx_i2c = NULL;
+ struct clk *clk;
+ void __iomem *reg_base;
+ int ret = 0;
+
+ zx_i2c = devm_kzalloc(&pdev->dev, sizeof(*zx_i2c), GFP_KERNEL);
+ if (!zx_i2c)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "missing io resource\n");
+ return -EINVAL;
+ }
+
+ reg_base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(reg_base))
+ return PTR_ERR(reg_base);
+
+ clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(clk)) {
+ dev_err(&pdev->dev, "missing controller clock");
+ return PTR_ERR(clk);
+ }
+
+ ret = clk_prepare_enable(clk);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to enable i2c_clk\n");
+ return ret;
+ }
+
+ of_property_read_u32(pdev->dev.of_node,
+ "clock-frequency", &zx_i2c->clk_freq);
+ zx_i2c->reg_base = reg_base;
+ zx_i2c->clk = clk;
+ zx_i2c->irq = platform_get_irq(pdev, 0);
+ zx_i2c->id = pdev->id;
+ zx_i2c->dev = &pdev->dev;
+
+ zx_i2c->pin_scl = devm_pinctrl_get_select(&pdev->dev, "scl");
+ if (IS_ERR(zx_i2c->pin_scl))
+ dev_info(&pdev->dev, "scl pin is not specified in dts\n");
+
+ zx_i2c->pin_sda = devm_pinctrl_get_select(&pdev->dev, "sda");
+ if (IS_ERR(zx_i2c->pin_sda))
+ dev_info(&pdev->dev, "sda pin is not specified in dts\n");
+
+ spin_lock_init(&zx_i2c->lock);
+ init_completion(&zx_i2c->complete);
+ platform_set_drvdata(pdev, zx_i2c);
+
+ ret = zx2967_i2c_reset_hardware(zx_i2c);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to initialize i2c controller\n");
+ goto unprepare_clk;
+ }
+
+ ret = devm_request_irq(&pdev->dev, zx_i2c->irq,
+ zx2967_i2c_isr, 0, dev_name(&pdev->dev), zx_i2c);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to request irq %i\n", zx_i2c->irq);
+ goto unprepare_clk;
+ }
+
+ i2c_set_adapdata(&zx_i2c->adap, zx_i2c);
+ zx_i2c->adap.owner = THIS_MODULE;
+ zx_i2c->adap.class = I2C_CLASS_DEPRECATED;
+ strlcpy(zx_i2c->adap.name, "zx2967 i2c adapter",
+ sizeof(zx_i2c->adap.name));
+ zx_i2c->adap.algo = &zx2967_i2c_algo;
+ zx_i2c->adap.dev.parent = &pdev->dev;
+ zx_i2c->adap.nr = pdev->id;
+ zx_i2c->adap.dev.of_node = pdev->dev.of_node;
+
+ ret = i2c_add_numbered_adapter(&zx_i2c->adap);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to add zx2967 i2c adapter\n");
+ goto unprepare_clk;
+ }
+
+ return 0;
+
+unprepare_clk:
+ clk_unprepare(zx_i2c->clk);
+ return ret;
+}
+
+static int zx2967_i2c_remove(struct platform_device *pdev)
+{
+ struct zx2967_i2c_info *zx_i2c = platform_get_drvdata(pdev);
+
+ i2c_del_adapter(&zx_i2c->adap);
+ clk_unprepare(zx_i2c->clk);
+
+ return 0;
+}
+
+static struct platform_driver zx2967_i2c_driver = {
+ .probe = zx2967_i2c_probe,
+ .remove = zx2967_i2c_remove,
+ .driver = {
+ .name = "zx2967_i2c",
+ .of_match_table = zx2967_i2c_of_match,
+ .pm = ZX2967_I2C_DEV_PM_OPS,
+ },
+};
+module_platform_driver(zx2967_i2c_driver);
+
+MODULE_AUTHOR("Baoyou Xie <baoyou.xie@linaro.org>");
+MODULE_DESCRIPTION("ZTE zx2967 I2C Bus Controller driver");
+MODULE_LICENSE("GPL v2");
--
2.7.4
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH v1 3/3] i2c: zx2967: add i2c controller driver for ZTE's zx2967 family
2017-01-20 8:43 ` [PATCH v1 3/3] i2c: zx2967: add i2c controller driver for ZTE's zx2967 family Baoyou Xie
@ 2017-01-20 21:45 ` Andy Shevchenko
2017-01-23 2:50 ` Shawn Guo
1 sibling, 0 replies; 5+ messages in thread
From: Andy Shevchenko @ 2017-01-20 21:45 UTC (permalink / raw)
To: Baoyou Xie
Cc: jun.nie, Wolfram Sang, Rob Herring, Mark Rutland,
linux-arm Mailing List, linux-i2c, devicetree, linux-kernel,
shawnguo, xie.baoyou, chen.chaokai, wang.qiang01
On Fri, Jan 20, 2017 at 10:43 AM, Baoyou Xie <baoyou.xie@linaro.org> wrote:
> This patch adds i2c controller driver for ZTE's zx2967 family.
>
> +config I2C_ZX2967
> + bool "ZTE zx2967 I2C support"
No module?
> + depends on ARCH_ZX
> + default y
Would architecture selects it instead?
> + help
> + Selecting this option will add ZX I2C driver.
> + If unsure, say y.
Two sentences about the same in spite 'default y'.
> +#define BW1 (u32)1
Do you really need casting?
> +#define I2C_STOP 0
> +#define I2C_MASTER (1 << 0)
BIT(0) ?
And so further.
> +#define I2C_INT_MASK 0x3f
GENMASK(6, 0) ?
> +#define I2C_ERROR_MASK (I2C_ERROR_DATA | I2C_ERROR_DEVICE)
Ditto.
GENMASK() with explicit numbers.
> +static int zx2967_i2c_flush_fifos(struct zx2967_i2c_info *zx_i2c)
> +{
> + u32 val = 0;
> + u32 offset = 0;
Useless assignments.
> +
> + if (zx_i2c->msg_rd) {
> + offset = REG_RDCONF;
> + val = I2C_RFIFO_RESET;
> + } else {
> + offset = REG_WRCONF;
> + val = I2C_WFIFO_RESET;
> + }
> +static int zx2967_i2c_empty_rx_fifo(struct zx2967_i2c_info *zx_i2c, u32 size)
> +{
> + u8 val[I2C_FIFO_MAX] = {0};
> + int i = 0;
Ditto.
> +
> + if (size == 0) {
Would it be the case?
> + dev_err(zx_i2c->dev, "size is invalid\n");
> + return -EINVAL;
> + }
And what happens even in that case if you just remove this check?
> +
> + zx2967_i2c_readsb(zx_i2c, val, REG_DATA, size);
> + for (i = 0; i < size; i++) {
> + *(zx_i2c->buf++) = val[i];
> + zx_i2c->residue--;
> + if (zx_i2c->residue <= 0)
> + break;
> +static int zx2967_i2c_fill_tx_fifo(struct zx2967_i2c_info *zx_i2c)
> +{
> + u8 *buf = zx_i2c->buf;
> + size_t residue = zx_i2c->residue;
> +
> + if (residue == 0) {
> + dev_err(zx_i2c->dev, "residue is %d\n", (int)residue);
> + return -EINVAL;
> + }
Ditto.
> +static void zx2967_enable_tenbit(struct zx2967_i2c_info *zx_i2c, __u16 addr)
> +{
> + u16 val = ((addr >> 7) & 0x7);
Redundant parens.
> + if (val > 0) {
if (!val)
return;
> +static int zx2967_i2c_xfer_msg(struct zx2967_i2c_info *zx_i2c,
> + struct i2c_msg *msg
> +{
> + unsigned long time_left = 0;
> + unsigned int i = 0;
Redundant assignment.
> +
> + if (msg->len == 0)
if (!msg...)
> + return -EINVAL;
> +static int zx2967_i2c_xfer(struct i2c_adapter *adap,
> + struct i2c_msg *msgs, int num)
> +{
> + int i;
> + int ret = 0;
Redundant. See below.
> + struct zx2967_i2c_info *zx_i2c = i2c_get_adapdata(adap);
Reverse tree, please.
> +
> + if (zx_i2c->is_suspended)
> + return -EBUSY;
> +
> + zx2967_i2c_writel(zx_i2c, (msgs->addr & 0x7f), REG_DEVADDR_L);
> + zx2967_i2c_writel(zx_i2c, (msgs->addr >> 7) & 0x7, REG_DEVADDR_H);
> + if (zx2967_i2c_readl(zx_i2c, REG_DEVADDR_H) > 0)
> + zx2967_enable_tenbit(zx_i2c, msgs->addr);
> +
> + for (i = 0; i < num; i++) {
int ret;
> + ret = zx2967_i2c_xfer_msg(zx_i2c, &msgs[i]);
> + if (num > 1)
> + usleep_range(1000, 2000);
> + if (ret)
> + break;
return ret;
> + }
> +
> + return ret ?: i;
return i;
And looking now, how i can't be num here?
> +}
> +{
> + struct zx2967_i2c_info *zx_i2c = i2c_get_adapdata(adap);
> + u32 val;
> + u8 buf[2];
> + unsigned long time_left;
Reverse tree.
> + usleep_range(1000, 2000);
> + switch (size) {
> + case I2C_SMBUS_BYTE:
> + case I2C_SMBUS_BYTE_DATA:
> + val = zx2967_i2c_readl(zx_i2c, REG_DATA);
> + data->byte = val;
> + break;
> + case I2C_SMBUS_WORD_DATA:
> + case I2C_SMBUS_PROC_CALL:
> + buf[0] = zx2967_i2c_readl(zx_i2c, REG_DATA);
> + buf[1] = zx2967_i2c_readl(zx_i2c, REG_DATA);
> + data->word = (buf[0] << 8) | buf[1];
> + break;
> + default:
> + dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
> + return -EOPNOTSUPP;
> + }
> +
> + return 0;
> +}
I would revisit those several loooong functions for splitting/refactoring.
> +
> +static u32 zx2967_i2c_func(struct i2c_adapter *adap)
> +{
> + return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
> + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
> + I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_PROC_CALL |
> + I2C_FUNC_I2C | I2C_FUNC_SMBUS_I2C_BLOCK;
> +}
It's just
#define XXX YY1 | YY2 | ...
> +#ifdef CONFIG_PM
> +static int zx2967_i2c_suspend(struct device *dev)
Switch to __maybe_unuse.
> +static int zx2967_i2c_probe(struct platform_device *pdev)
> +{
> + struct resource *res;
> + struct zx2967_i2c_info *zx_i2c = NULL;
Redundant assignment.
> + struct clk *clk;
> + void __iomem *reg_base;
Reverse tree for all above until top of this function.
> + int ret = 0;
Redundant assignment.
> +
> + zx_i2c = devm_kzalloc(&pdev->dev, sizeof(*zx_i2c), GFP_KERNEL);
> + if (!zx_i2c)
> + return -ENOMEM;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + if (!res) {
> + dev_err(&pdev->dev, "missing io resource\n");
> + return -EINVAL;
> + }
> +
Completely redundant lines of code.
> + reg_base = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(reg_base))
> + return PTR_ERR(reg_base);
> +
> + clk = devm_clk_get(&pdev->dev, NULL);
> + if (IS_ERR(clk)) {
> + dev_err(&pdev->dev, "missing controller clock");
> + return PTR_ERR(clk);
> + }
> +
> + ret = clk_prepare_enable(clk);
> + if (ret) {
> + dev_err(&pdev->dev, "failed to enable i2c_clk\n");
> + return ret;
> + }
> +
> + of_property_read_u32(pdev->dev.of_node,
> + "clock-frequency", &zx_i2c->clk_freq);
devce_property_read_uXX();
> + zx_i2c->reg_base = reg_base;
> + zx_i2c->clk = clk;
> + zx_i2c->irq = platform_get_irq(pdev, 0);
Is this optional?
Otherwise has to be checked.
> + zx_i2c->id = pdev->id;
> + zx_i2c->dev = &pdev->dev;
> +
> + zx_i2c->pin_scl = devm_pinctrl_get_select(&pdev->dev, "scl");
> + if (IS_ERR(zx_i2c->pin_scl))
> + dev_info(&pdev->dev, "scl pin is not specified in dts\n");
> +
> + zx_i2c->pin_sda = devm_pinctrl_get_select(&pdev->dev, "sda");
> + if (IS_ERR(zx_i2c->pin_sda))
> + dev_info(&pdev->dev, "sda pin is not specified in dts\n");
> +
> + spin_lock_init(&zx_i2c->lock);
> + init_completion(&zx_i2c->complete);
> + platform_set_drvdata(pdev, zx_i2c);
> +
> + ret = zx2967_i2c_reset_hardware(zx_i2c);
> + if (ret) {
> + dev_err(&pdev->dev, "failed to initialize i2c controller\n");
> + goto unprepare_clk;
> + }
> +
> + ret = devm_request_irq(&pdev->dev, zx_i2c->irq,
> + zx2967_i2c_isr, 0, dev_name(&pdev->dev), zx_i2c);
> + if (ret) {
> + dev_err(&pdev->dev, "failed to request irq %i\n", zx_i2c->irq);
> + goto unprepare_clk;
> + }
> +
> + i2c_set_adapdata(&zx_i2c->adap, zx_i2c);
> + zx_i2c->adap.owner = THIS_MODULE;
Do you need this?
> + zx_i2c->adap.class = I2C_CLASS_DEPRECATED;
> + strlcpy(zx_i2c->adap.name, "zx2967 i2c adapter",
> + sizeof(zx_i2c->adap.name));
> + zx_i2c->adap.algo = &zx2967_i2c_algo;
> + zx_i2c->adap.dev.parent = &pdev->dev;
> + zx_i2c->adap.nr = pdev->id;
> + zx_i2c->adap.dev.of_node = pdev->dev.of_node;
> +
> + ret = i2c_add_numbered_adapter(&zx_i2c->adap);
> + if (ret) {
> + dev_err(&pdev->dev, "failed to add zx2967 i2c adapter\n");
> + goto unprepare_clk;
> + }
> +
> + return 0;
> +
> +unprepare_clk:
err_clk_unprepare:
> + clk_unprepare(zx_i2c->clk);
Perhaps clk_disable_unprepare();
> + return ret;
> +}
> +
> +static int zx2967_i2c_remove(struct platform_device *pdev)
> +{
> + struct zx2967_i2c_info *zx_i2c = platform_get_drvdata(pdev);
> +
> + i2c_del_adapter(&zx_i2c->adap);
> + clk_unprepare(zx_i2c->clk);
Ditto.
> +
> + return 0;
> +}
> +MODULE_AUTHOR("Baoyou Xie <baoyou.xie@linaro.org>");
> +MODULE_DESCRIPTION("ZTE zx2967 I2C Bus Controller driver");
> +MODULE_LICENSE("GPL v2");
When bool in Kconfig this all redundant.
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v1 3/3] i2c: zx2967: add i2c controller driver for ZTE's zx2967 family
2017-01-20 8:43 ` [PATCH v1 3/3] i2c: zx2967: add i2c controller driver for ZTE's zx2967 family Baoyou Xie
2017-01-20 21:45 ` Andy Shevchenko
@ 2017-01-23 2:50 ` Shawn Guo
1 sibling, 0 replies; 5+ messages in thread
From: Shawn Guo @ 2017-01-23 2:50 UTC (permalink / raw)
To: Baoyou Xie
Cc: jun.nie, wsa, robh+dt, mark.rutland, linux-arm-kernel, linux-i2c,
devicetree, linux-kernel, xie.baoyou, chen.chaokai, wang.qiang01
On Fri, Jan 20, 2017 at 04:43:47PM +0800, Baoyou Xie wrote:
> +static int zx2967_i2c_probe(struct platform_device *pdev)
> +{
> + struct resource *res;
> + struct zx2967_i2c_info *zx_i2c = NULL;
> + struct clk *clk;
> + void __iomem *reg_base;
> + int ret = 0;
> +
> + zx_i2c = devm_kzalloc(&pdev->dev, sizeof(*zx_i2c), GFP_KERNEL);
> + if (!zx_i2c)
> + return -ENOMEM;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + if (!res) {
> + dev_err(&pdev->dev, "missing io resource\n");
> + return -EINVAL;
> + }
> +
> + reg_base = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(reg_base))
> + return PTR_ERR(reg_base);
> +
> + clk = devm_clk_get(&pdev->dev, NULL);
> + if (IS_ERR(clk)) {
> + dev_err(&pdev->dev, "missing controller clock");
> + return PTR_ERR(clk);
> + }
> +
> + ret = clk_prepare_enable(clk);
> + if (ret) {
> + dev_err(&pdev->dev, "failed to enable i2c_clk\n");
> + return ret;
> + }
> +
> + of_property_read_u32(pdev->dev.of_node,
> + "clock-frequency", &zx_i2c->clk_freq);
> + zx_i2c->reg_base = reg_base;
> + zx_i2c->clk = clk;
> + zx_i2c->irq = platform_get_irq(pdev, 0);
> + zx_i2c->id = pdev->id;
> + zx_i2c->dev = &pdev->dev;
> +
> + zx_i2c->pin_scl = devm_pinctrl_get_select(&pdev->dev, "scl");
> + if (IS_ERR(zx_i2c->pin_scl))
> + dev_info(&pdev->dev, "scl pin is not specified in dts\n");
> +
> + zx_i2c->pin_sda = devm_pinctrl_get_select(&pdev->dev, "sda");
> + if (IS_ERR(zx_i2c->pin_sda))
> + dev_info(&pdev->dev, "sda pin is not specified in dts\n");
I don't understand why this is necessary. For most cases, we only need
to specify needed pins in property 'pinctrl-0' and 'default' in
'pinctrl-names', and pinctrl/driver core will just set up the pins for
the device.
Shawn
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2017-01-23 2:50 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-01-20 8:43 [PATCH v1 1/3] dt: bindings: add documentation for zx2967 family i2c controller Baoyou Xie
2017-01-20 8:43 ` [PATCH v1 2/3] MAINTAINERS: add zx2967 i2c controller driver to ARM ZTE architecture Baoyou Xie
2017-01-20 8:43 ` [PATCH v1 3/3] i2c: zx2967: add i2c controller driver for ZTE's zx2967 family Baoyou Xie
2017-01-20 21:45 ` Andy Shevchenko
2017-01-23 2:50 ` Shawn Guo
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