[PATCH] i2c: s3c24xx: allow device core to setup default pin configuration

[Heiko Stübner]

Hi Thomas,

Am Montag, 4. März 2013, 14:42:53 schrieb Thomas Abraham:
> With device core now able to setup the default pin configuration,
> the call to devm_pinctrl_get_select_default can be removed. And
> the pin configuration code based on the deprecated Samsung specific
> gpio bindings is also removed.
> 
> Signed-off-by: Thomas Abraham <thomas.abraham at linaro.org>
> ---
> 
> Hi Heiko, Tomasz,
> 
> We have to make a choice on the path forward for pinctrl support
> on Samsung platforms. We have three cases to deal with.
> 
> A. Samsung platforms without DT support.
> B. Samsung platforms with DT support using old Samsung specific
>    gpio bindings for pin-configuration (s3c24xx and s3x64xx).
> C. Samsung platforms with DT support using using pinctrl based
>    pin-configurations (Exynos4 and Exynos5).
> 
> For [A], we just let the platform specific callbacks handle the
> pin setup. For [B] and [C], based on Linus Walleij's pin grab
> by device core patch and subsequent discussions with him on the
> mailing list, would it be acceptable that we discontinue support
> for [B] in Samsung SoC device drivers. This will impact your
> current DT work on s3c24xx and s3c64xx platforms. Pinctrl is
> inevitable and we have to migrate to it. Instead of workarounds
> to maintain support for [B], it might be better that we migrate
> s3c24xx and s3c64xx platforms to pinctrl.
> 
> Please do let us know your opinion on this.

As discusses in the other thread, I'm in favor of going forward this way and 
not to invest unnecessary energy in keeping the non-pinctrl stuff alive.

Pinctrl for at least the s3c2416 [0] is already on my playground-wishlist, but 
I'm still in the process of getting to know it.

So for this patch:
Acked-by: Heiko Stuebner <heiko at sntech.de>


Heiko


[0] in contrast to what the gpio-samsung driver implies, the s3c24xx pin banks 
are not uniform between SoCs, making this more difficult still :-)


>  drivers/i2c/busses/i2c-s3c2410.c |   67
> +------------------------------------- 1 files changed, 1 insertions(+),
> 66 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-s3c2410.c
> b/drivers/i2c/busses/i2c-s3c2410.c index f6b880b..703272c 100644
> --- a/drivers/i2c/busses/i2c-s3c2410.c
> +++ b/drivers/i2c/busses/i2c-s3c2410.c
> @@ -37,8 +37,6 @@
>  #include <linux/slab.h>
>  #include <linux/io.h>
>  #include <linux/of_i2c.h>
> -#include <linux/of_gpio.h>
> -#include <linux/pinctrl/consumer.h>
> 
>  #include <asm/irq.h>
> 
> @@ -84,8 +82,6 @@ struct s3c24xx_i2c {
>  	struct i2c_adapter	adap;
> 
>  	struct s3c2410_platform_i2c	*pdata;
> -	int			gpios[2];
> -	struct pinctrl          *pctrl;
>  #ifdef CONFIG_CPU_FREQ
>  	struct notifier_block	freq_transition;
>  #endif
> @@ -856,57 +852,6 @@ static inline void
> s3c24xx_i2c_deregister_cpufreq(struct s3c24xx_i2c *i2c) }
>  #endif
> 
> -#ifdef CONFIG_OF
> -static int s3c24xx_i2c_parse_dt_gpio(struct s3c24xx_i2c *i2c)
> -{
> -	int idx, gpio, ret;
> -
> -	if (i2c->quirks & QUIRK_NO_GPIO)
> -		return 0;
> -
> -	for (idx = 0; idx < 2; idx++) {
> -		gpio = of_get_gpio(i2c->dev->of_node, idx);
> -		if (!gpio_is_valid(gpio)) {
> -			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) {
> -			dev_err(i2c->dev, "gpio [%d] request failed\n", gpio);
> -			goto free_gpio;
> -		}
> -	}
> -	return 0;
> -
> -free_gpio:
> -	while (--idx >= 0)
> -		gpio_free(i2c->gpios[idx]);
> -	return -EINVAL;
> -}
> -
> -static void s3c24xx_i2c_dt_gpio_free(struct s3c24xx_i2c *i2c)
> -{
> -	unsigned int idx;
> -
> -	if (i2c->quirks & QUIRK_NO_GPIO)
> -		return;
> -
> -	for (idx = 0; idx < 2; idx++)
> -		gpio_free(i2c->gpios[idx]);
> -}
> -#else
> -static int s3c24xx_i2c_parse_dt_gpio(struct s3c24xx_i2c *i2c)
> -{
> -	return 0;
> -}
> -
> -static void s3c24xx_i2c_dt_gpio_free(struct s3c24xx_i2c *i2c)
> -{
> -}
> -#endif
> -
>  /* s3c24xx_i2c_init
>   *
>   * initialise the controller, set the IO lines and frequency
> @@ -1054,15 +999,9 @@ static int s3c24xx_i2c_probe(struct platform_device
> *pdev) i2c->adap.algo_data = i2c;
>  	i2c->adap.dev.parent = &pdev->dev;
> 
> -	i2c->pctrl = devm_pinctrl_get_select_default(i2c->dev);
> -
>  	/* inititalise the i2c gpio lines */
> -
> -	if (i2c->pdata->cfg_gpio) {
> +	if (i2c->pdata->cfg_gpio)
>  		i2c->pdata->cfg_gpio(to_platform_device(i2c->dev));
> -	} else if (IS_ERR(i2c->pctrl) && s3c24xx_i2c_parse_dt_gpio(i2c)) {
> -		return -EINVAL;
> -	}
> 
>  	/* initialise the i2c controller */
> 
> @@ -1140,10 +1079,6 @@ static int s3c24xx_i2c_remove(struct platform_device
> *pdev) i2c_del_adapter(&i2c->adap);
> 
>  	clk_disable_unprepare(i2c->clk);
> -
> -	if (pdev->dev.of_node && IS_ERR(i2c->pctrl))
> -		s3c24xx_i2c_dt_gpio_free(i2c);
> -
>  	return 0;
>  }