These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / drivers / i2c / busses / i2c-imx.c

diff --git a/kernel/drivers/i2c/busses/i2c-imx.c b/kernel/drivers/i2c/busses/i2c-imx.c
index a53a7dd..d4d8536 100644 (file)
--- a/kernel/drivers/i2c/busses/i2c-imx.c
+++ b/kernel/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;
 };
@@ -241,7 +248,7 @@ static struct imx_i2c_hwdata vf610_i2c_hwdata = {
 
 };
 
-static struct platform_device_id imx_i2c_devtype[] = {
+static const struct platform_device_id imx_i2c_devtype[] = {
        {
                .name = "imx1-i2c",
                .driver_data = (kernel_ulong_t)&imx1_i2c_hwdata,
@@ -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) {