| Message ID | 1413776535-10123-4-git-send-email-wenyou.yang@atmel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Oct 20, 2014 at 11:42:14AM +0800, Wenyou Yang wrote: > 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@atmel.com> Acked by: Ludovic Desroches <ludovic.desroches@atmel.com> > --- > drivers/i2c/busses/i2c-at91.c | 12 +++++++++++- > 1 file changed, 11 insertions(+), 1 deletion(-) > > diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c > index 8f408f8..ed2c382 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 */ > @@ -748,6 +749,8 @@ 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; > @@ -850,8 +853,10 @@ static int at91_twi_suspend(struct device *dev) > { > struct at91_twi_dev *twi_dev = dev_get_drvdata(dev); > > - if (!pm_runtime_suspended(dev)) > + if (!pm_runtime_suspended(dev)) { > clk_disable_unprepare(twi_dev->clk); > + pinctrl_pm_select_sleep_state(dev); > + } > > return 0; > } > @@ -862,6 +867,7 @@ static int at91_twi_resume(struct device *dev) > int ret; > > if (!pm_runtime_suspended(dev)) { > + pinctrl_pm_select_default_state(dev); > ret = clk_prepare_enable(twi_dev->clk); > if (ret) > return ret; > @@ -881,6 +887,8 @@ static int at91_twi_runtime_suspend(struct device *dev) > > clk_disable_unprepare(twi_dev->clk); > > + pinctrl_pm_select_sleep_state(dev); > + > return 0; > } > > @@ -888,6 +896,8 @@ 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); > } > #endif > -- > 1.7.9.5 >
Wenyou Yang <wenyou.yang@atmel.com> writes: > 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@atmel.com> This patch is a good example of why you should just have the ->suspend function call the same function as ->runtime_suspend. If you do that, rather than having to add the pinctrl_pm* calls bo both system PM and runtime PM functions, you could've just added them to the runtime PM functions. Kevin
diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c index 8f408f8..ed2c382 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 */ @@ -748,6 +749,8 @@ 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; @@ -850,8 +853,10 @@ static int at91_twi_suspend(struct device *dev) { struct at91_twi_dev *twi_dev = dev_get_drvdata(dev); - if (!pm_runtime_suspended(dev)) + if (!pm_runtime_suspended(dev)) { clk_disable_unprepare(twi_dev->clk); + pinctrl_pm_select_sleep_state(dev); + } return 0; } @@ -862,6 +867,7 @@ static int at91_twi_resume(struct device *dev) int ret; if (!pm_runtime_suspended(dev)) { + pinctrl_pm_select_default_state(dev); ret = clk_prepare_enable(twi_dev->clk); if (ret) return ret; @@ -881,6 +887,8 @@ static int at91_twi_runtime_suspend(struct device *dev) clk_disable_unprepare(twi_dev->clk); + pinctrl_pm_select_sleep_state(dev); + return 0; } @@ -888,6 +896,8 @@ 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); } #endif
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@atmel.com> --- drivers/i2c/busses/i2c-at91.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-)