Re: [RFC PATCH 3/4] pinctrl: at91: improve pinconf_set/get functionrobustness

From: Jean-Christophe PLAGNIOL-VILLARD
Date: Sat Sep 14 2013 - 14:14:56 EST


On 09:49 Fri 13 Sep , Boris BREZILLON wrote:
> Reset caller's config variable before setting current config flags to avoid
> erronous config return.
>
> DEBOUNCE and DEGLITCH options are mutually exclusive. Return an error if they
> are both defined in the config.
> Do not call set_deglitch if DEBOUNCE is enabled to avoid reseting the IFSR
> register (which will result in disabling the debounce filter).
>
> Signed-off-by: Boris BREZILLON <b.brezillon@xxxxxxxxxxx>
> ---
> drivers/pinctrl/pinctrl-at91.c | 18 +++++++++++++-----
> 1 file changed, 13 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/pinctrl/pinctrl-at91.c b/drivers/pinctrl/pinctrl-at91.c
> index 6624bce..ac9dbea 100644
> --- a/drivers/pinctrl/pinctrl-at91.c
> +++ b/drivers/pinctrl/pinctrl-at91.c
> @@ -724,6 +724,7 @@ static int at91_pinconf_get(struct pinctrl_dev *pctldev,
> dev_dbg(info->dev, "%s:%d, pin_id=%d, config=0x%lx", __func__, __LINE__, pin_id, *config);
> pio = pin_to_controller(info, pin_to_bank(pin_id));
> pin = pin_id % MAX_NB_GPIO_PER_BANK;
> + *config = 0;
>
> if (at91_mux_get_multidrive(pio, pin))
> *config |= MULTI_DRIVE;
> @@ -757,13 +758,20 @@ static int at91_pinconf_set(struct pinctrl_dev *pctldev,
> if (config & PULL_UP && config & PULL_DOWN)
> return -EINVAL;
>
> - at91_mux_set_pullup(pio, mask, config & PULL_UP);
> - at91_mux_set_multidrive(pio, mask, config & MULTI_DRIVE);
> - if (info->ops->set_deglitch)
> - info->ops->set_deglitch(pio, mask, config & DEGLITCH);
> - if (info->ops->set_debounce)
> + if (config & DEBOUNCE && config & DEGLITCH)
> + return -EINVAL;
here ok
> +
> + if (config & DEBOUNCE) {
> + if (!info->ops->set_debounce)
> + return -ENOTSUPP;
a warning is better here than an error
> +
> info->ops->set_debounce(pio, mask, config & DEBOUNCE,
> (config & DEBOUNCE_VAL) >> DEBOUNCE_VAL_SHIFT);
> + } else if (info->ops->set_deglitch)
> + info->ops->set_deglitch(pio, mask, config & DEGLITCH);
> +


> + at91_mux_set_pullup(pio, mask, config & PULL_UP);
> + at91_mux_set_multidrive(pio, mask, config & MULTI_DRIVE);

> if (info->ops->set_pulldown)
> info->ops->set_pulldown(pio, mask, config & PULL_DOWN);
> if (info->ops->disable_schmitt_trig && config & DIS_SCHMIT)
> --
> 1.7.9.5
>
>
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