diff mbox

[v3,3/3] i2c/at91: adopt pinctrl support

Message ID 1414133417-11530-4-git-send-email-wenyou.yang@atmel.com
State Superseded
Headers show

Commit Message

Wenyou Yang Oct. 24, 2014, 6:50 a.m. UTC
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(+)

Comments

Wolfram Sang Nov. 8, 2014, 6:03 p.m. UTC | #1
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
>
Wenyou Yang Nov. 10, 2014, 1:49 a.m. UTC | #2
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
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diff mbox

Patch

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);
 }