@@ -24,6 +24,7 @@
#include <linux/io.h>
#include <linux/pm_runtime.h>
#include <linux/platform_data/i2c-nomadik.h>
+#include <linux/pinctrl/consumer.h>
#define DRIVER_NAME "nmk-i2c"
@@ -145,6 +146,10 @@ struct i2c_nmk_client {
* @stop: stop condition.
* @xfer_complete: acknowledge completion for a I2C message.
* @result: controller propogated result.
+ * @pinctrl: pinctrl handle.
+ * @pins_default: default state for the pins.
+ * @pins_idle: idle state for the pins.
+ * @pins_sleep: sleep state for the pins.
* @busy: Busy doing transfer.
*/
struct nmk_i2c_dev {
@@ -158,6 +163,11 @@ struct nmk_i2c_dev {
int stop;
struct completion xfer_complete;
int result;
+ /* Three pin states - default, idle & sleep */
+ struct pinctrl *pinctrl;
+ struct pinctrl_state *pins_default;
+ struct pinctrl_state *pins_idle;
+ struct pinctrl_state *pins_sleep;
bool busy;
};
@@ -648,6 +658,15 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap,
goto out_clk;
}
+ /* Optionaly enable pins to be muxed in and configured */
+ if (!IS_ERR(dev->pins_default)) {
+ status = pinctrl_select_state(dev->pinctrl,
+ dev->pins_default);
+ if (status)
+ dev_err(&dev->adev->dev,
+ "could not set default pins\n");
+ }
+
status = init_hw(dev);
if (status)
goto out;
@@ -675,6 +694,15 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap,
out:
clk_disable_unprepare(dev->clk);
out_clk:
+ /* Optionally let pins go into idle state */
+ if (!IS_ERR(dev->pins_idle)) {
+ status = pinctrl_select_state(dev->pinctrl,
+ dev->pins_idle);
+ if (status)
+ dev_err(&dev->adev->dev,
+ "could not set pins to idle state\n");
+ }
+
pm_runtime_put_sync(&dev->adev->dev);
dev->busy = false;
@@ -869,15 +897,44 @@ static int nmk_i2c_suspend(struct device *dev)
{
struct amba_device *adev = to_amba_device(dev);
struct nmk_i2c_dev *nmk_i2c = amba_get_drvdata(adev);
+ int ret;
if (nmk_i2c->busy)
return -EBUSY;
+ if (!IS_ERR(nmk_i2c->pins_sleep)) {
+ ret = pinctrl_select_state(nmk_i2c->pinctrl,
+ nmk_i2c->pins_sleep);
+ if (ret)
+ dev_err(dev,
+ "could not set pins to sleep state\n");
+ }
+
return 0;
}
static int nmk_i2c_resume(struct device *dev)
{
+ struct amba_device *adev = to_amba_device(dev);
+ struct nmk_i2c_dev *nmk_i2c = amba_get_drvdata(adev);
+ int ret;
+
+ /* First go to the default state */
+ if (!IS_ERR(nmk_i2c->pins_default)) {
+ ret = pinctrl_select_state(nmk_i2c->pinctrl,
+ nmk_i2c->pins_default);
+ if (ret)
+ dev_err(dev,
+ "could not set pins to default state\n");
+ }
+ /* Then let's idle the pins until the next transfer happens */
+ if (!IS_ERR(nmk_i2c->pins_idle)) {
+ ret = pinctrl_select_state(nmk_i2c->pinctrl,
+ nmk_i2c->pins_idle);
+ if (ret)
+ dev_err(dev,
+ "could not set pins to idle state\n");
+ }
return 0;
}
#else
@@ -941,6 +998,40 @@ static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id)
dev->adev = adev;
amba_set_drvdata(adev, dev);
+ dev->pinctrl = devm_pinctrl_get(&adev->dev);
+ if (IS_ERR(dev->pinctrl)) {
+ ret = PTR_ERR(dev->pinctrl);
+ goto err_pinctrl;
+ }
+
+ dev->pins_default = pinctrl_lookup_state(dev->pinctrl,
+ PINCTRL_STATE_DEFAULT);
+ if (IS_ERR(dev->pins_default))
+ dev_err(&adev->dev, "could not get default pinstate\n");
+ else {
+ ret = pinctrl_select_state(dev->pinctrl,
+ dev->pins_default);
+ if (ret)
+ dev_dbg(&adev->dev, "could not set default pinstate\n");
+ }
+
+ dev->pins_idle = pinctrl_lookup_state(dev->pinctrl,
+ PINCTRL_STATE_IDLE);
+ if (IS_ERR(dev->pins_idle))
+ dev_dbg(&adev->dev, "could not get idle pinstate\n");
+ else {
+ /* If possible, let's go to idle until the first transfer */
+ ret = pinctrl_select_state(dev->pinctrl,
+ dev->pins_idle);
+ if (ret)
+ dev_dbg(&adev->dev, "could not set idle pinstate\n");
+ }
+
+ dev->pins_sleep = pinctrl_lookup_state(dev->pinctrl,
+ PINCTRL_STATE_SLEEP);
+ if (IS_ERR(dev->pins_sleep))
+ dev_dbg(&adev->dev, "could not get sleep pinstate\n");
+
dev->virtbase = ioremap(adev->res.start, resource_size(&adev->res));
if (!dev->virtbase) {
ret = -ENOMEM;
@@ -964,6 +1055,12 @@ static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id)
goto err_no_clk;
}
+ ret = clk_prepare(dev->clk);
+ if (ret) {
+ dev_err(&adev->dev, "can't prepare clock\n");
+ goto err_prep_clk;
+ }
+
adap = &dev->adap;
adap->dev.parent = &adev->dev;
adap->owner = THIS_MODULE;
@@ -999,6 +1096,8 @@ static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id)
return 0;
err_add_adap:
+ clk_unprepare(dev->clk);
+ err_prep_clk:
clk_put(dev->clk);
err_no_clk:
free_irq(dev->irq, dev);
@@ -1007,6 +1106,7 @@ static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id)
err_no_ioremap:
amba_set_drvdata(adev, NULL);
kfree(dev);
+ err_pinctrl:
err_no_mem:
return ret;
@@ -1027,6 +1127,7 @@ static int nmk_i2c_remove(struct amba_device *adev)
iounmap(dev->virtbase);
if (res)
release_mem_region(res->start, resource_size(res));
+ clk_unprepare(dev->clk);
clk_put(dev->clk);
pm_runtime_disable(&adev->dev);
amba_set_drvdata(adev, NULL);