| Message ID | 1414133417-11530-4-git-send-email-wenyou.yang@atmel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Oct 24, 2014 at 02:50:17PM +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> > --- > 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 6a84a2a..290caf1 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); > + Do we really need this in probe? Isn't that default? I'm not sure, though... > 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 >
Hi Wolfram, > -----Original Message----- > From: Wolfram Sang [mailto:wsa@the-dreams.de] > Sent: Sunday, November 09, 2014 2:03 AM > To: Yang, Wenyou > Cc: Desroches, Ludovic; linux-i2c@vger.kernel.org; linux-kernel@vger.kernel.org; > Ferre, Nicolas; khilman@kernel.org; linux-arm-kernel@lists.infradead.org > Subject: Re: [PATCH v3 3/3] i2c/at91: adopt pinctrl support > > On Fri, Oct 24, 2014 at 02:50:17PM +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> > > --- > > 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 6a84a2a..290caf1 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); > > + > > Do we really need this in probe? Isn't that default? I'm not sure, though... No, we don't need it. It is called by the function pinctrl_bind_pins(struct device *dev) in drivers/base/pinctrl.c I will remove it, and send it again. > > > 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 > > Best Regards, Wenyou Yang
diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c index 6a84a2a..290caf1 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); }
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 | 7 +++++++ 1 file changed, 7 insertions(+)