From: Patrice Chotard <patrice.chotard@xxxxxxxxxxxxxx>
Amend the I2C nomadik pin controller to optionally take a pin control
handle and set the state of the pins to "default" on boot and
before performing an i2c transfer, and to "sleep" after an i2c xfer.
Signed-off-by: Patrice Chotard <patrice.chotard@xxxxxxxxxxxxxx>
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
---
drivers/i2c/busses/i2c-nomadik.c | 41 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 41 insertions(+)
diff --git a/drivers/i2c/busses/i2c-nomadik.c b/drivers/i2c/busses/i2c-nomadik.c
index 1b898b6..8ed3962 100644
--- a/drivers/i2c/busses/i2c-nomadik.c
+++ b/drivers/i2c/busses/i2c-nomadik.c
@@ -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"
@@ -158,6 +159,10 @@ struct nmk_i2c_dev {
int stop;
struct completion xfer_complete;
int result;
+ /* Two optional pin states - default & sleep */
+ struct pinctrl *pinctrl;
+ struct pinctrl_state *pins_default;
+ struct pinctrl_state *pins_sleep;
bool busy;
};
@@ -642,6 +647,15 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap,
pm_runtime_get_sync(&dev->adev->dev);
+ /* 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");
+ }
+
clk_enable(dev->clk);
status = init_hw(dev);
@@ -670,6 +684,16 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap,
out:
clk_disable(dev->clk);
+
+ /* Optionally let pins go into sleep states */
+ if (!IS_ERR(dev->pins_sleep)) {
+ status = pinctrl_select_state(dev->pinctrl,
+ dev->pins_sleep);
+ if (status)
+ dev_err(&dev->adev->dev,
+ "could not set pins to sleep state\n");
+ }
+
pm_runtime_put_sync(&dev->adev->dev);
dev->busy = false;
@@ -936,6 +960,22 @@ 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");
+
+ 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;
@@ -1002,6 +1042,7 @@ 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;
--
1.7.11.3
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