1 files changed, 101 insertions, 1 deletions

diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c
index 54819fb4f82e..4788a32afb86 100644
--- a/drivers/i2c/busses/i2c-davinci.c
+++ b/drivers/i2c/busses/i2c-davinci.c
@@ -60,6 +60,12 @@
 #define DAVINCI_I2C_IVR_REG     0x28
 #define DAVINCI_I2C_EMDR_REG    0x2c
 #define DAVINCI_I2C_PSC_REG     0x30
+#define DAVINCI_I2C_FUNC_REG    0x48
+#define DAVINCI_I2C_DIR_REG     0x4c
+#define DAVINCI_I2C_DIN_REG     0x50
+#define DAVINCI_I2C_DOUT_REG    0x54
+#define DAVINCI_I2C_DSET_REG    0x58
+#define DAVINCI_I2C_DCLR_REG    0x5c
 
 #define DAVINCI_I2C_IVR_AAS     0x07
 #define DAVINCI_I2C_IVR_SCD     0x06
@@ -93,6 +99,29 @@
 #define DAVINCI_I2C_IMR_NACK    BIT(1)
 #define DAVINCI_I2C_IMR_AL      BIT(0)
 
+/* set SDA and SCL as GPIO */
+#define DAVINCI_I2C_FUNC_PFUNC0 BIT(0)
+
+/* set SCL as output when used as GPIO*/
+#define DAVINCI_I2C_DIR_PDIR0   BIT(0)
+/* set SDA as output when used as GPIO*/
+#define DAVINCI_I2C_DIR_PDIR1   BIT(1)
+
+/* read SCL GPIO level */
+#define DAVINCI_I2C_DIN_PDIN0 BIT(0)
+/* read SDA GPIO level */
+#define DAVINCI_I2C_DIN_PDIN1 BIT(1)
+
+/*set the SCL GPIO high */
+#define DAVINCI_I2C_DSET_PDSET0 BIT(0)
+/*set the SDA GPIO high */
+#define DAVINCI_I2C_DSET_PDSET1 BIT(1)
+
+/* set the SCL GPIO low */
+#define DAVINCI_I2C_DCLR_PDCLR0 BIT(0)
+/* set the SDA GPIO low */
+#define DAVINCI_I2C_DCLR_PDCLR1 BIT(1)
+
 struct davinci_i2c_dev {
         struct device           *dev;
         void __iomem            *base;
@@ -253,6 +282,71 @@ static struct i2c_bus_recovery_info davinci_i2c_gpio_recovery_info = {
         .unprepare_recovery = davinci_i2c_unprepare_recovery,
 };
 
+static void davinci_i2c_set_scl(struct i2c_adapter *adap, int val)
+{
+        struct davinci_i2c_dev *dev = i2c_get_adapdata(adap);
+
+        if (val)
+                davinci_i2c_write_reg(dev, DAVINCI_I2C_DSET_REG,
+                                      DAVINCI_I2C_DSET_PDSET0);
+        else
+                davinci_i2c_write_reg(dev, DAVINCI_I2C_DCLR_REG,
+                                      DAVINCI_I2C_DCLR_PDCLR0);
+}
+
+static int davinci_i2c_get_scl(struct i2c_adapter *adap)
+{
+        struct davinci_i2c_dev *dev = i2c_get_adapdata(adap);
+        int val;
+
+        /* read the state of SCL */
+        val = davinci_i2c_read_reg(dev, DAVINCI_I2C_DIN_REG);
+        return val & DAVINCI_I2C_DIN_PDIN0;
+}
+
+static int davinci_i2c_get_sda(struct i2c_adapter *adap)
+{
+        struct davinci_i2c_dev *dev = i2c_get_adapdata(adap);
+        int val;
+
+        /* read the state of SDA */
+        val = davinci_i2c_read_reg(dev, DAVINCI_I2C_DIN_REG);
+        return val & DAVINCI_I2C_DIN_PDIN1;
+}
+
+static void davinci_i2c_scl_prepare_recovery(struct i2c_adapter *adap)
+{
+        struct davinci_i2c_dev *dev = i2c_get_adapdata(adap);
+
+        davinci_i2c_prepare_recovery(adap);
+
+        /* SCL output, SDA input */
+        davinci_i2c_write_reg(dev, DAVINCI_I2C_DIR_REG, DAVINCI_I2C_DIR_PDIR0);
+
+        /* change to GPIO mode */
+        davinci_i2c_write_reg(dev, DAVINCI_I2C_FUNC_REG,
+                              DAVINCI_I2C_FUNC_PFUNC0);
+}
+
+static void davinci_i2c_scl_unprepare_recovery(struct i2c_adapter *adap)
+{
+        struct davinci_i2c_dev *dev = i2c_get_adapdata(adap);
+
+        /* change back to I2C mode */
+        davinci_i2c_write_reg(dev, DAVINCI_I2C_FUNC_REG, 0);
+
+        davinci_i2c_unprepare_recovery(adap);
+}
+
+static struct i2c_bus_recovery_info davinci_i2c_scl_recovery_info = {
+        .recover_bus = i2c_generic_scl_recovery,
+        .set_scl = davinci_i2c_set_scl,
+        .get_scl = davinci_i2c_get_scl,
+        .get_sda = davinci_i2c_get_sda,
+        .prepare_recovery = davinci_i2c_scl_prepare_recovery,
+        .unprepare_recovery = davinci_i2c_scl_unprepare_recovery,
+};
+
 /*
  * Waiting for bus not busy
  */
@@ -660,6 +754,10 @@ static int davinci_i2c_probe(struct platform_device *pdev)
                 if (!of_property_read_u32(pdev->dev.of_node, "clock-frequency",
                         &prop))
                         dev->pdata->bus_freq = prop / 1000;
+
+                dev->pdata->has_pfunc =
+                        of_property_read_bool(pdev->dev.of_node,
+                                              "ti,has-pfunc");
         } else if (!dev->pdata) {
                 dev->pdata = &davinci_i2c_platform_data_default;
         }
@@ -701,7 +799,9 @@ static int davinci_i2c_probe(struct platform_device *pdev)
         adap->timeout = DAVINCI_I2C_TIMEOUT;
         adap->dev.of_node = pdev->dev.of_node;
 
-        if (dev->pdata->scl_pin) {
+        if (dev->pdata->has_pfunc)
+                adap->bus_recovery_info = &davinci_i2c_scl_recovery_info;
+        else if (dev->pdata->scl_pin) {
                 adap->bus_recovery_info = &davinci_i2c_gpio_recovery_info;
                 adap->bus_recovery_info->scl_gpio = dev->pdata->scl_pin;
                 adap->bus_recovery_info->sda_gpio = dev->pdata->sda_pin;