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 <[email protected]>
---
Changes from V1:
- make the hw feature structure as part of tegra device structure in
place of copying the member.
- Remove check for extra M_NOSTART flag if it is not supported in xfer function.
Please note that this should go on tegra common clock source tree to avoid conflicts.
drivers/i2c/busses/i2c-tegra.c | 61 ++++++++++++++++++++++++++++++---------
1 files changed, 47 insertions(+), 14 deletions(-)
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 7149625..2f74236 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>
@@ -114,8 +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),
--
1.7.1.1
Tegra I2C driver enables the fast clock during initialization
and does not disable till driver removed.
Enable this clock before transfer and disable after transfer done.
Signed-off-by: Laxman Dewangan <[email protected]>
Reviewed-by: Wolfram Sang <[email protected]>
---
Changes from V1:
- Rebased again on patch 1.
drivers/i2c/busses/i2c-tegra.c | 35 ++++++++++++++++++++++++++++-------
1 files changed, 28 insertions(+), 7 deletions(-)
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 2f74236..20c35fa 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -363,12 +363,36 @@ 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->div_clk);
+ tegra_i2c_clock_enable(i2c_dev);
tegra_periph_reset_assert(i2c_dev->div_clk);
udelay(2);
@@ -399,7 +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->div_clk);
+ tegra_i2c_clock_disable(i2c_dev);
if (i2c_dev->irq_disabled) {
i2c_dev->irq_disabled = 0;
@@ -575,7 +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->div_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)) {
@@ -588,7 +612,7 @@ static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
if (ret)
break;
}
- clk_disable_unprepare(i2c_dev->div_clk);
+ tegra_i2c_clock_disable(i2c_dev);
return ret ?: i;
}
@@ -724,8 +748,6 @@ static int __devinit tegra_i2c_probe(struct platform_device *pdev)
return ret;
}
- clk_prepare_enable(i2c_dev->fast_clk);
-
i2c_set_adapdata(&i2c_dev->adapter, i2c_dev);
i2c_dev->adapter.owner = THIS_MODULE;
i2c_dev->adapter.class = I2C_CLASS_HWMON;
@@ -739,7 +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->fast_clk);
return ret;
}
--
1.7.1.1
On Sun, Aug 19, 2012 at 12:47:46AM +0530, Laxman Dewangan wrote:
> 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 <[email protected]>
> ---
> Changes from V1:
> - make the hw feature structure as part of tegra device structure in
> place of copying the member.
> - Remove check for extra M_NOSTART flag if it is not supported in xfer function.
>
> Please note that this should go on tegra common clock source tree to avoid conflicts.
Looks good to me regarding the I2C part:
Reviewed-by: Wolfram Sang <[email protected]>
--
Pengutronix e.K. | Wolfram Sang |
Industrial Linux Solutions | http://www.pengutronix.de/ |
On 08/18/2012 01:17 PM, Laxman Dewangan wrote:
> 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.
Thanks, applied the series to Tegra's for-3.7/drivers-i2c branch.
Note that I had to fix up patch 1 to remove const on the tegra*_i2c_hw
variable declarations to avoid compiler warnings when assigning pointers
into tegra_i2c_of_match[].data.
On Monday 20 August 2012 10:45 PM, Stephen Warren wrote:
> On 08/18/2012 01:17 PM, Laxman Dewangan wrote:
>> 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.
> Thanks, applied the series to Tegra's for-3.7/drivers-i2c branch.
>
> Note that I had to fix up patch 1 to remove const on the tegra*_i2c_hw
> variable declarations to avoid compiler warnings when assigning pointers
> into tegra_i2c_of_match[].data.
Thanks for correction but
I did not get this warning and when saw the structure, it is declared as
const type only..
struct of_device_id
{
char name[32];
char type[32];
char compatible[128];
#ifdef __KERNEL__
const void *data;
#else
kernel_ulong_t data;
#endif
};
On 08/20/2012 11:10 AM, Laxman Dewangan wrote:
> On Monday 20 August 2012 10:45 PM, Stephen Warren wrote:
>> On 08/18/2012 01:17 PM, Laxman Dewangan wrote:
>>> 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.
>> Thanks, applied the series to Tegra's for-3.7/drivers-i2c branch.
>>
>> Note that I had to fix up patch 1 to remove const on the tegra*_i2c_hw
>> variable declarations to avoid compiler warnings when assigning pointers
>> into tegra_i2c_of_match[].data.
>
> Thanks for correction but
> I did not get this warning and when saw the structure, it is declared as
> const type only..
Ah. This is something new in linux-next but not in 3.6-rc2. It was
introduced by:
98d7bbb of: add const to struct *of_device_id.data
I'll revert the modifications I made to the patch, and ignore the
warnings in Tegra's for-next; they won't be present in 3.7 presumably.