[PATCH 2/3] i2c/at91: add support for system PM

Wenyou Yang
2014-10-20T03:42:13Z

Signed-off-by: Wenyou Yang <wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
---
drivers/i2c/busses/i2c-at91.c | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)

diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
index 03b9f48..8f408f8 100644
--- a/drivers/i2c/busses/i2c-at91.c
+++ b/drivers/i2c/busses/i2c-at91.c
@@ -845,6 +845,35 @@ static int at91_twi_remove(struct platform_device *pdev)
}

#ifdef CONFIG_PM
+#ifdef CONFIG_PM_SLEEP
+static int at91_twi_suspend(struct device *dev)
+{
+ struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
+
+ if (!pm_runtime_suspended(dev))
+ clk_disable_unprepare(twi_dev->clk);
+
+ return 0;
+}
+
+static int at91_twi_resume(struct device *dev)
+{
+ struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
+ int ret;
+
+ if (!pm_runtime_suspended(dev)) {
+ ret = clk_prepare_enable(twi_dev->clk);
+ if (ret)
+ return ret;
+ }
+
+ pm_runtime_mark_last_busy(dev);
+ pm_request_autosuspend(dev);
+
+ return 0;
+}
+#endif
+
#ifdef CONFIG_PM_RUNTIME
static int at91_twi_runtime_suspend(struct device *dev)
{
@@ -864,6 +893,7 @@ static int at91_twi_runtime_resume(struct device *dev)
#endif

static const struct dev_pm_ops at91_twi_pm = {
+ SET_SYSTEM_SLEEP_PM_OPS(at91_twi_suspend, at91_twi_resume)
SET_RUNTIME_PM_OPS(at91_twi_runtime_suspend,
at91_twi_runtime_resume, NULL)
};
--
1.7.9.5