[PATCH v2] i2c: s3c2410: Add fix for i2c suspend/resume

[PATCH v2] i2c: s3c2410: Add fix for i2c suspend/resume

[Abhilash Kesavan]

The I2C driver makes a gpio_request during initialization. This request
happens again on resume and fails due to the earlier successful request.
Re-factor the code to only initialize the gpios during probe.

Errors on resume without this:
[   16.020000] s3c-i2c s3c2440-i2c.0: gpio [42] request failed
[   16.020000] s3c-i2c s3c2440-i2c.1: gpio [44] request failed
[   16.020000] s3c-i2c s3c2440-i2c.2: gpio [6] request failed

Signed-off-by: Abhilash Kesavan <a.kesavan-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
---
Changes from v1:
Refactor code to initialize gpios only during probe

 drivers/i2c/busses/i2c-s3c2410.c |   26 +++++++++++++++++++-------
 1 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c
index 081e261..0ca321b 100644
--- a/drivers/i2c/busses/i2c-s3c2410.c
+++ b/drivers/i2c/busses/i2c-s3c2410.c
@@ -856,6 +856,7 @@ static int s3c24xx_i2c_parse_dt_gpio(struct s3c24xx_i2c *i2c)
 			dev_err(i2c->dev, "invalid gpio[%d]: %d\n", idx, gpio);
 			goto free_gpio;
 		}
+		i2c->gpios[idx] = gpio;
 
 		ret = gpio_request(gpio, "i2c-bus");
 		if (ret) {
@@ -892,6 +893,18 @@ static void s3c24xx_i2c_dt_gpio_free(struct s3c24xx_i2c *i2c)
 }
 #endif
 
+static int s3c24xx_i2c_cfg_gpio(struct s3c24xx_i2c *i2c)
+{
+	struct s3c2410_platform_i2c *pdata = i2c->pdata;
+
+	if (pdata->cfg_gpio)
+		pdata->cfg_gpio(to_platform_device(i2c->dev));
+	else if (IS_ERR(i2c->pctrl) && s3c24xx_i2c_parse_dt_gpio(i2c))
+		return -EINVAL;
+
+	return 0;
+}
+
 /* s3c24xx_i2c_init
  *
  * initialise the controller, set the IO lines and frequency
@@ -907,13 +920,6 @@ static int s3c24xx_i2c_init(struct s3c24xx_i2c *i2c)
 
 	pdata = i2c->pdata;
 
-	/* inititalise the gpio */
-
-	if (pdata->cfg_gpio)
-		pdata->cfg_gpio(to_platform_device(i2c->dev));
-	else if (IS_ERR(i2c->pctrl) && s3c24xx_i2c_parse_dt_gpio(i2c))
-		return -EINVAL;
-
 	/* write slave address */
 
 	writeb(pdata->slave_addr, i2c->regs + S3C2410_IICADD);
@@ -1054,6 +1060,12 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev)
 
 	i2c->pctrl = devm_pinctrl_get_select_default(i2c->dev);
 
+	/* inititalise the i2c gpio lines */
+
+	ret = s3c24xx_i2c_cfg_gpio(i2c);
+	if (ret != 0)
+		goto err_clk;
+
 	/* initialise the i2c controller */
 
 	ret = s3c24xx_i2c_init(i2c);
-- 
1.6.6.1

Re: [PATCH v2] i2c: s3c2410: Add fix for i2c suspend/resume

[Wolfram Sang]

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Hi,

On Mon, Nov 19, 2012 at 02:30:26PM +0530, Abhilash Kesavan wrote:
> The I2C driver makes a gpio_request during initialization. This request
> happens again on resume and fails due to the earlier successful request.
> Re-factor the code to only initialize the gpios during probe.
> 
> Errors on resume without this:
> [   16.020000] s3c-i2c s3c2440-i2c.0: gpio [42] request failed
> [   16.020000] s3c-i2c s3c2440-i2c.1: gpio [44] request failed
> [   16.020000] s3c-i2c s3c2440-i2c.2: gpio [6] request failed
> 
> Signed-off-by: Abhilash Kesavan <a.kesavan-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
> ---
> Changes from v1:
> Refactor code to initialize gpios only during probe
> 
>  drivers/i2c/busses/i2c-s3c2410.c |   26 +++++++++++++++++++-------
>  1 files changed, 19 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c
> index 081e261..0ca321b 100644
> --- a/drivers/i2c/busses/i2c-s3c2410.c
> +++ b/drivers/i2c/busses/i2c-s3c2410.c
> @@ -856,6 +856,7 @@ static int s3c24xx_i2c_parse_dt_gpio(struct s3c24xx_i2c *i2c)
>  			dev_err(i2c->dev, "invalid gpio[%d]: %d\n", idx, gpio);
>  			goto free_gpio;
>  		}
> +		i2c->gpios[idx] = gpio;

Without this line, gpios won't be freed at all, right? This should be a
separate patch then, since it fixes a seperate issue.

>  
>  		ret = gpio_request(gpio, "i2c-bus");
>  		if (ret) {
> @@ -892,6 +893,18 @@ static void s3c24xx_i2c_dt_gpio_free(struct s3c24xx_i2c *i2c)
>  }
>  #endif
>  
> +static int s3c24xx_i2c_cfg_gpio(struct s3c24xx_i2c *i2c)
> +{
> +	struct s3c2410_platform_i2c *pdata = i2c->pdata;
> +
> +	if (pdata->cfg_gpio)
> +		pdata->cfg_gpio(to_platform_device(i2c->dev));
> +	else if (IS_ERR(i2c->pctrl) && s3c24xx_i2c_parse_dt_gpio(i2c))
> +		return -EINVAL;
> +
> +	return 0;
> +}
> +
>  /* s3c24xx_i2c_init
>   *
>   * initialise the controller, set the IO lines and frequency
> @@ -907,13 +920,6 @@ static int s3c24xx_i2c_init(struct s3c24xx_i2c *i2c)
>  
>  	pdata = i2c->pdata;
>  
> -	/* inititalise the gpio */
> -
> -	if (pdata->cfg_gpio)
> -		pdata->cfg_gpio(to_platform_device(i2c->dev));
> -	else if (IS_ERR(i2c->pctrl) && s3c24xx_i2c_parse_dt_gpio(i2c))
> -		return -EINVAL;
> -
>  	/* write slave address */
>  
>  	writeb(pdata->slave_addr, i2c->regs + S3C2410_IICADD);
> @@ -1054,6 +1060,12 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev)
>  
>  	i2c->pctrl = devm_pinctrl_get_select_default(i2c->dev);
>  
> +	/* inititalise the i2c gpio lines */
> +
> +	ret = s3c24xx_i2c_cfg_gpio(i2c);
> +	if (ret != 0)
> +		goto err_clk;
> +

I don't think the seperate function is needed here, just copy the code block?

Thanks,

   Wolfram

-- 
Pengutronix e.K.                           | Wolfram Sang                |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |

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