On Tue, Oct 04, 2016 at 09:51:10AM +0800, Chen-Yu Tsai wrote:
> The sunxi pinctrl driver only caches whatever pinconf setting was last
> set on a given pingroup. This is not particularly helpful, nor is it
> correct.
>
> Fix this by actually reading the hardware registers and returning
> the correct results or error codes. Also filter out unsupported
> pinconf settings. Since this driver has a peculiar setup of 1 pin
> per group, we can support both pin and pingroup pinconf setting
> read back with the same code. The sunxi_pconf_reg helper and code
> structure is inspired by pinctrl-msm.
>
> With this done we can also claim to support generic pinconf, by
> setting .is_generic = true in pinconf_ops.
>
> Signed-off-by: Chen-Yu Tsai <wens@xxxxxxxx>
> ---
> drivers/pinctrl/sunxi/pinctrl-sunxi.c | 85 +++++++++++++++++++++++++++++++++--
> 1 file changed, 82 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/pinctrl/sunxi/pinctrl-sunxi.c b/drivers/pinctrl/sunxi/pinctrl-sunxi.c
> index 54455af566ec..609843c9a65c 100644
> --- a/drivers/pinctrl/sunxi/pinctrl-sunxi.c
> +++ b/drivers/pinctrl/sunxi/pinctrl-sunxi.c
> @@ -10,6 +10,7 @@
> * warranty of any kind, whether express or implied.
> */
>
> +#include <dt-bindings/pinctrl/sun4i-a10.h>
> #include <linux/io.h>
> #include <linux/clk.h>
> #include <linux/gpio/driver.h>
> @@ -269,15 +270,91 @@ static const struct pinctrl_ops sunxi_pctrl_ops = {
> .get_group_pins = sunxi_pctrl_get_group_pins,
> };
>
> +static int sunxi_pconf_reg(unsigned pin, enum pin_config_param param,
> + u32 *offset, u32 *shift, u32 *mask)
> +{
> + switch (param) {
> + case PIN_CONFIG_DRIVE_STRENGTH:
> + *offset = sunxi_dlevel_reg(pin);
> + *shift = sunxi_dlevel_offset(pin);
> + *mask = DLEVEL_PINS_MASK;
> + break;
> +
> + case PIN_CONFIG_BIAS_PULL_UP:
> + case PIN_CONFIG_BIAS_PULL_DOWN:
> + case PIN_CONFIG_BIAS_DISABLE:
> + *offset = sunxi_pull_reg(pin);
> + *shift = sunxi_pull_offset(pin);
> + *mask = PULL_PINS_MASK;
> + break;
> +
> + default:
> + return -ENOTSUPP;
> + }
> +
> + return 0;
> +}
> +
> +static int sunxi_pconf_get(struct pinctrl_dev *pctldev, unsigned pin,
> + unsigned long *config)
> +{
> + struct sunxi_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);
> + enum pin_config_param param = pinconf_to_config_param(*config);
> + u32 offset, shift, mask, val;
> + u16 arg;
> + int ret;
> +
> + pin -= pctl->desc->pin_base;
> +
> + ret = sunxi_pconf_reg(pin, param, &offset, &shift, &mask);
> + if (ret < 0)
> + return ret;
> +
> + val = (readl(pctl->membase + offset) >> shift) & mask;
> +
> + switch (pinconf_to_config_param(*config)) {
> + case PIN_CONFIG_DRIVE_STRENGTH:
> + arg = (val + 1) * 10;
> + break;
> +
> + case PIN_CONFIG_BIAS_PULL_UP:
> + if (val != SUN4I_PINCTRL_PULL_UP)
> + return -EINVAL;
> + arg = 1; /* hardware is weak pull-up */
> + break;
> +
> + case PIN_CONFIG_BIAS_PULL_DOWN:
> + if (val != SUN4I_PINCTRL_PULL_DOWN)
> + return -EINVAL;
> + arg = 1; /* hardware is weak pull-down */
> + break;
> +
> + case PIN_CONFIG_BIAS_DISABLE:
> + if (val != SUN4I_PINCTRL_NO_PULL)
> + return -EINVAL;
> + arg = 0;
> + break;
> +
> + default:
> + /* sunxi_pconf_reg should catch anything unsupported */
> + WARN_ON(1);
> + return -ENOTSUPP;
This should be EINVAL. The operation is supported, but one of the
argument is not valid.
Maxime
--
Maxime Ripard, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
Attachment:
signature.asc
Description: PGP signature
