i2c: tegra: I2_M_NOSTART functionality not supported in Tegra20
authorLaxman Dewangan <ldewangan@nvidia.com>
Sat, 18 Aug 2012 19:17:46 +0000 (00:47 +0530)
committerStephen Warren <swarren@nvidia.com>
Thu, 13 Sep 2012 17:40:30 +0000 (11:40 -0600)
Tegra20 i2c controller does not support the continue transfer
which implements the I2C_M_NOSTART functionality of i2c
protocol mangling.
Removing the I2C_M_NOSTART functionality support for Tegra20.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
drivers/i2c/busses/i2c-tegra.c

index 8514d3a..ce70147 100644 (file)
@@ -27,6 +27,7 @@
 #include <linux/slab.h>
 #include <linux/i2c-tegra.h>
 #include <linux/of_i2c.h>
+#include <linux/of_device.h>
 #include <linux/module.h>
 
 #include <asm/unaligned.h>
@@ -114,8 +115,18 @@ enum msg_end_type {
 };
 
 /**
+ * struct tegra_i2c_hw_feature : Different HW support on Tegra
+ * @has_continue_xfer_support: Continue transfer supports.
+ */
+
+struct tegra_i2c_hw_feature {
+       bool has_continue_xfer_support;
+};
+
+/**
  * struct tegra_i2c_dev        - per device i2c context
  * @dev: device reference for power management
+ * @hw: Tegra i2c hw feature.
  * @adapter: core i2c layer adapter information
  * @div_clk: clock reference for div clock of i2c controller.
  * @fast_clk: clock reference for fast clock of i2c controller.
@@ -133,6 +144,7 @@ enum msg_end_type {
  */
 struct tegra_i2c_dev {
        struct device *dev;
+       const struct tegra_i2c_hw_feature *hw;
        struct i2c_adapter adapter;
        struct clk *div_clk;
        struct clk *fast_clk;
@@ -582,8 +594,13 @@ static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
 
 static u32 tegra_i2c_func(struct i2c_adapter *adap)
 {
-       return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR |
-               I2C_FUNC_PROTOCOL_MANGLING | I2C_FUNC_NOSTART;
+       struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
+       u32 ret = I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR |
+                               I2C_FUNC_PROTOCOL_MANGLING;
+
+       if (i2c_dev->hw->has_continue_xfer_support)
+               ret |= I2C_FUNC_NOSTART;
+       return ret;
 }
 
 static const struct i2c_algorithm tegra_i2c_algo = {
@@ -591,6 +608,25 @@ static const struct i2c_algorithm tegra_i2c_algo = {
        .functionality  = tegra_i2c_func,
 };
 
+static const struct tegra_i2c_hw_feature tegra20_i2c_hw = {
+       .has_continue_xfer_support = false,
+};
+
+static const struct tegra_i2c_hw_feature tegra30_i2c_hw = {
+       .has_continue_xfer_support = true,
+};
+
+#if defined(CONFIG_OF)
+/* Match table for of_platform binding */
+static const struct of_device_id tegra_i2c_of_match[] __devinitconst = {
+       { .compatible = "nvidia,tegra30-i2c", .data = &tegra30_i2c_hw, },
+       { .compatible = "nvidia,tegra20-i2c", .data = &tegra20_i2c_hw, },
+       { .compatible = "nvidia,tegra20-i2c-dvc", .data = &tegra20_i2c_hw, },
+       {},
+};
+MODULE_DEVICE_TABLE(of, tegra_i2c_of_match);
+#endif
+
 static int __devinit tegra_i2c_probe(struct platform_device *pdev)
 {
        struct tegra_i2c_dev *i2c_dev;
@@ -659,11 +695,18 @@ static int __devinit tegra_i2c_probe(struct platform_device *pdev)
                        i2c_dev->bus_clk_rate = be32_to_cpup(prop);
        }
 
-       if (pdev->dev.of_node)
+       i2c_dev->hw = &tegra20_i2c_hw;
+
+       if (pdev->dev.of_node) {
+               const struct of_device_id *match;
+               match = of_match_device(of_match_ptr(tegra_i2c_of_match),
+                                               &pdev->dev);
+               i2c_dev->hw = match->data;
                i2c_dev->is_dvc = of_device_is_compatible(pdev->dev.of_node,
                                                "nvidia,tegra20-i2c-dvc");
-       else if (pdev->id == 3)
+       } else if (pdev->id == 3) {
                i2c_dev->is_dvc = 1;
+       }
        init_completion(&i2c_dev->msg_complete);
 
        platform_set_drvdata(pdev, i2c_dev);
@@ -751,16 +794,6 @@ static SIMPLE_DEV_PM_OPS(tegra_i2c_pm, tegra_i2c_suspend, tegra_i2c_resume);
 #define TEGRA_I2C_PM   NULL
 #endif
 
-#if defined(CONFIG_OF)
-/* Match table for of_platform binding */
-static const struct of_device_id tegra_i2c_of_match[] __devinitconst = {
-       { .compatible = "nvidia,tegra20-i2c", },
-       { .compatible = "nvidia,tegra20-i2c-dvc", },
-       {},
-};
-MODULE_DEVICE_TABLE(of, tegra_i2c_of_match);
-#endif
-
 static struct platform_driver tegra_i2c_driver = {
        .probe   = tegra_i2c_probe,
        .remove  = __devexit_p(tegra_i2c_remove),