summaryrefslogtreecommitdiff
path: root/drivers/i2c/busses/i2c-imx.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/i2c/busses/i2c-imx.c')
-rw-r--r--drivers/i2c/busses/i2c-imx.c74
1 files changed, 73 insertions, 1 deletions
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index 785aa674a..d4d853680 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -49,6 +49,8 @@
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_dma.h>
+#include <linux/of_gpio.h>
+#include <linux/pinctrl/consumer.h>
#include <linux/platform_data/i2c-imx.h>
#include <linux/platform_device.h>
#include <linux/sched.h>
@@ -207,6 +209,11 @@ struct imx_i2c_struct {
unsigned int cur_clk;
unsigned int bitrate;
const struct imx_i2c_hwdata *hwdata;
+ struct i2c_bus_recovery_info rinfo;
+
+ struct pinctrl *pinctrl;
+ struct pinctrl_state *pinctrl_pins_default;
+ struct pinctrl_state *pinctrl_pins_gpio;
struct imx_i2c_dma *dma;
};
@@ -461,7 +468,7 @@ static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx)
{
if (imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR) & I2SR_RXAK) {
dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK\n", __func__);
- return -EIO; /* No ACK */
+ return -ENXIO; /* No ACK */
}
dev_dbg(&i2c_imx->adapter.dev, "<%s> ACK received\n", __func__);
@@ -896,6 +903,13 @@ static int i2c_imx_xfer(struct i2c_adapter *adapter,
/* Start I2C transfer */
result = i2c_imx_start(i2c_imx);
+ if (result) {
+ if (i2c_imx->adapter.bus_recovery_info) {
+ i2c_recover_bus(&i2c_imx->adapter);
+ result = i2c_imx_start(i2c_imx);
+ }
+ }
+
if (result)
goto fail0;
@@ -956,6 +970,55 @@ fail0:
return (result < 0) ? result : num;
}
+static void i2c_imx_prepare_recovery(struct i2c_adapter *adap)
+{
+ struct imx_i2c_struct *i2c_imx;
+
+ i2c_imx = container_of(adap, struct imx_i2c_struct, adapter);
+
+ pinctrl_select_state(i2c_imx->pinctrl, i2c_imx->pinctrl_pins_gpio);
+}
+
+static void i2c_imx_unprepare_recovery(struct i2c_adapter *adap)
+{
+ struct imx_i2c_struct *i2c_imx;
+
+ i2c_imx = container_of(adap, struct imx_i2c_struct, adapter);
+
+ pinctrl_select_state(i2c_imx->pinctrl, i2c_imx->pinctrl_pins_default);
+}
+
+static void i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
+ struct platform_device *pdev)
+{
+ struct i2c_bus_recovery_info *rinfo = &i2c_imx->rinfo;
+
+ i2c_imx->pinctrl_pins_default = pinctrl_lookup_state(i2c_imx->pinctrl,
+ PINCTRL_STATE_DEFAULT);
+ i2c_imx->pinctrl_pins_gpio = pinctrl_lookup_state(i2c_imx->pinctrl,
+ "gpio");
+ rinfo->sda_gpio = of_get_named_gpio_flags(pdev->dev.of_node,
+ "sda-gpios", 0, NULL);
+ rinfo->scl_gpio = of_get_named_gpio_flags(pdev->dev.of_node,
+ "scl-gpios", 0, NULL);
+
+ if (!gpio_is_valid(rinfo->sda_gpio) ||
+ !gpio_is_valid(rinfo->scl_gpio) ||
+ IS_ERR(i2c_imx->pinctrl_pins_default) ||
+ IS_ERR(i2c_imx->pinctrl_pins_gpio)) {
+ dev_dbg(&pdev->dev, "recovery information incomplete\n");
+ return;
+ }
+
+ dev_dbg(&pdev->dev, "using scl-gpio %d and sda-gpio %d for recovery\n",
+ rinfo->sda_gpio, rinfo->scl_gpio);
+
+ rinfo->prepare_recovery = i2c_imx_prepare_recovery;
+ rinfo->unprepare_recovery = i2c_imx_unprepare_recovery;
+ rinfo->recover_bus = i2c_generic_gpio_recovery;
+ i2c_imx->adapter.bus_recovery_info = rinfo;
+}
+
static u32 i2c_imx_func(struct i2c_adapter *adapter)
{
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL
@@ -1023,6 +1086,13 @@ static int i2c_imx_probe(struct platform_device *pdev)
dev_err(&pdev->dev, "can't enable I2C clock\n");
return ret;
}
+
+ i2c_imx->pinctrl = devm_pinctrl_get(&pdev->dev);
+ if (IS_ERR(i2c_imx->pinctrl)) {
+ ret = PTR_ERR(i2c_imx->pinctrl);
+ goto clk_disable;
+ }
+
/* Request IRQ */
ret = devm_request_irq(&pdev->dev, irq, i2c_imx_isr, 0,
pdev->name, i2c_imx);
@@ -1049,6 +1119,8 @@ static int i2c_imx_probe(struct platform_device *pdev)
i2c_imx, IMX_I2C_I2CR);
imx_i2c_write_reg(i2c_imx->hwdata->i2sr_clr_opcode, i2c_imx, IMX_I2C_I2SR);
+ i2c_imx_init_recovery_info(i2c_imx, pdev);
+
/* Add I2C adapter */
ret = i2c_add_numbered_adapter(&i2c_imx->adapter);
if (ret < 0) {