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-rw-r--r--drivers/i2c/busses/i2c-tegra.c130
1 files changed, 92 insertions, 38 deletions
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 9a08c57bc93..f981ac4e678 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -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>
@@ -114,11 +115,21 @@ 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
- * @clk: clock reference for i2c controller
- * @i2c_clk: clock reference for i2c bus
+ * @div_clk: clock reference for div clock of i2c controller.
+ * @fast_clk: clock reference for fast clock of i2c controller.
* @base: ioremapped registers cookie
* @cont_id: i2c controller id, used for for packet header
* @irq: irq number of transfer complete interrupt
@@ -133,9 +144,10 @@ enum msg_end_type {
*/
struct tegra_i2c_dev {
struct device *dev;
+ const struct tegra_i2c_hw_feature *hw;
struct i2c_adapter adapter;
- struct clk *clk;
- struct clk *i2c_clk;
+ struct clk *div_clk;
+ struct clk *fast_clk;
void __iomem *base;
int cont_id;
int irq;
@@ -351,16 +363,40 @@ static void tegra_dvc_init(struct tegra_i2c_dev *i2c_dev)
dvc_writel(i2c_dev, val, DVC_CTRL_REG1);
}
+static inline int tegra_i2c_clock_enable(struct tegra_i2c_dev *i2c_dev)
+{
+ int ret;
+ ret = clk_prepare_enable(i2c_dev->fast_clk);
+ if (ret < 0) {
+ dev_err(i2c_dev->dev,
+ "Enabling fast clk failed, err %d\n", ret);
+ return ret;
+ }
+ ret = clk_prepare_enable(i2c_dev->div_clk);
+ if (ret < 0) {
+ dev_err(i2c_dev->dev,
+ "Enabling div clk failed, err %d\n", ret);
+ clk_disable_unprepare(i2c_dev->fast_clk);
+ }
+ return ret;
+}
+
+static inline void tegra_i2c_clock_disable(struct tegra_i2c_dev *i2c_dev)
+{
+ clk_disable_unprepare(i2c_dev->div_clk);
+ clk_disable_unprepare(i2c_dev->fast_clk);
+}
+
static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev)
{
u32 val;
int err = 0;
- clk_prepare_enable(i2c_dev->clk);
+ tegra_i2c_clock_enable(i2c_dev);
- tegra_periph_reset_assert(i2c_dev->clk);
+ tegra_periph_reset_assert(i2c_dev->div_clk);
udelay(2);
- tegra_periph_reset_deassert(i2c_dev->clk);
+ tegra_periph_reset_deassert(i2c_dev->div_clk);
if (i2c_dev->is_dvc)
tegra_dvc_init(i2c_dev);
@@ -369,7 +405,7 @@ static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev)
(0x2 << I2C_CNFG_DEBOUNCE_CNT_SHIFT);
i2c_writel(i2c_dev, val, I2C_CNFG);
i2c_writel(i2c_dev, 0, I2C_INT_MASK);
- clk_set_rate(i2c_dev->clk, i2c_dev->bus_clk_rate * 8);
+ clk_set_rate(i2c_dev->div_clk, i2c_dev->bus_clk_rate * 8);
if (!i2c_dev->is_dvc) {
u32 sl_cfg = i2c_readl(i2c_dev, I2C_SL_CNFG);
@@ -387,7 +423,7 @@ static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev)
if (tegra_i2c_flush_fifos(i2c_dev))
err = -ETIMEDOUT;
- clk_disable_unprepare(i2c_dev->clk);
+ tegra_i2c_clock_disable(i2c_dev);
if (i2c_dev->irq_disabled) {
i2c_dev->irq_disabled = 0;
@@ -563,7 +599,7 @@ static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
if (i2c_dev->is_suspended)
return -EBUSY;
- clk_prepare_enable(i2c_dev->clk);
+ tegra_i2c_clock_enable(i2c_dev);
for (i = 0; i < num; i++) {
enum msg_end_type end_type = MSG_END_STOP;
if (i < (num - 1)) {
@@ -576,14 +612,19 @@ static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
if (ret)
break;
}
- clk_disable_unprepare(i2c_dev->clk);
+ tegra_i2c_clock_disable(i2c_dev);
return ret ?: i;
}
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 = {
@@ -591,13 +632,32 @@ 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;
struct tegra_i2c_platform_data *pdata = pdev->dev.platform_data;
struct resource *res;
- struct clk *clk;
- struct clk *i2c_clk;
+ struct clk *div_clk;
+ struct clk *fast_clk;
const unsigned int *prop;
void __iomem *base;
int irq;
@@ -622,16 +682,16 @@ static int __devinit tegra_i2c_probe(struct platform_device *pdev)
}
irq = res->start;
- clk = devm_clk_get(&pdev->dev, NULL);
- if (IS_ERR(clk)) {
+ div_clk = devm_clk_get(&pdev->dev, "div-clk");
+ if (IS_ERR(div_clk)) {
dev_err(&pdev->dev, "missing controller clock");
- return PTR_ERR(clk);
+ return PTR_ERR(div_clk);
}
- i2c_clk = devm_clk_get(&pdev->dev, "i2c");
- if (IS_ERR(i2c_clk)) {
+ fast_clk = devm_clk_get(&pdev->dev, "fast-clk");
+ if (IS_ERR(fast_clk)) {
dev_err(&pdev->dev, "missing bus clock");
- return PTR_ERR(i2c_clk);
+ return PTR_ERR(fast_clk);
}
i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL);
@@ -641,8 +701,8 @@ static int __devinit tegra_i2c_probe(struct platform_device *pdev)
}
i2c_dev->base = base;
- i2c_dev->clk = clk;
- i2c_dev->i2c_clk = i2c_clk;
+ i2c_dev->div_clk = div_clk;
+ i2c_dev->fast_clk = fast_clk;
i2c_dev->adapter.algo = &tegra_i2c_algo;
i2c_dev->irq = irq;
i2c_dev->cont_id = pdev->id;
@@ -659,11 +719,18 @@ 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);
@@ -681,8 +748,6 @@ static int __devinit tegra_i2c_probe(struct platform_device *pdev)
return ret;
}
- clk_prepare_enable(i2c_dev->i2c_clk);
-
i2c_set_adapdata(&i2c_dev->adapter, i2c_dev);
i2c_dev->adapter.owner = THIS_MODULE;
i2c_dev->adapter.class = I2C_CLASS_HWMON;
@@ -696,7 +761,6 @@ static int __devinit tegra_i2c_probe(struct platform_device *pdev)
ret = i2c_add_numbered_adapter(&i2c_dev->adapter);
if (ret) {
dev_err(&pdev->dev, "Failed to add I2C adapter\n");
- clk_disable_unprepare(i2c_dev->i2c_clk);
return ret;
}
@@ -751,16 +815,6 @@ 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),
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-07 13:51:22 +0000