[PATCH v2 3/3] i2c/at91: adopt pinctrl support

[Wenyou Yang]

Amend the i2c at91 pin controller to optionally take a pin control
handle and set the state of the pins to:

- "default" on boot, resume and before performing an transfer
- "sleep" on suspend()

This should make it possible to optimize energy usage for the pins
both for the suspend/resume cycle

Signed-off-by: Wenyou Yang <wenyou.yang at atmel.com>
Acked-by: Ludovic Desroches <ludovic.desroches at atmel.com>
---
 drivers/i2c/busses/i2c-at91.c |    7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
index 8f8fd2a..7075834 100644
--- a/drivers/i2c/busses/i2c-at91.c
+++ b/drivers/i2c/busses/i2c-at91.c
@@ -32,6 +32,7 @@
 #include <linux/slab.h>
 #include <linux/platform_data/dma-atmel.h>
 #include <linux/pm_runtime.h>
+#include <linux/pinctrl/consumer.h>
 
 #define DEFAULT_TWI_CLK_HZ		100000		/* max 400 Kbits/s */
 #define AT91_I2C_TIMEOUT	msecs_to_jiffies(100)	/* transfer timeout */
@@ -747,6 +748,8 @@ static int at91_twi_probe(struct platform_device *pdev)
 	u32 phy_addr;
 	u32 bus_clk_rate;
 
+	pinctrl_pm_select_default_state(&pdev->dev);
+
 	dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
 	if (!dev)
 		return -ENOMEM;
@@ -851,6 +854,8 @@ static int at91_twi_runtime_suspend(struct device *dev)
 
 	clk_disable_unprepare(twi_dev->clk);
 
+	pinctrl_pm_select_sleep_state(dev);
+
 	return 0;
 }
 
@@ -858,6 +863,8 @@ static int at91_twi_runtime_resume(struct device *dev)
 {
 	struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
 
+	pinctrl_pm_select_default_state(dev);
+
 	return clk_prepare_enable(twi_dev->clk);
 }
 
-- 
1.7.9.5