[PATCH 1/2] pinctrl: qcom: disable GPIO groups with no pins
Stephen Boyd
sboyd at codeaurora.org
Fri Jul 14 10:11:48 PDT 2017
On 07/13, Timur Tabi wrote:
> diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c
> index 273badd..e915db4 100644
> --- a/drivers/pinctrl/qcom/pinctrl-msm.c
> +++ b/drivers/pinctrl/qcom/pinctrl-msm.c
> @@ -165,7 +165,22 @@ static int msm_pinmux_set_mux(struct pinctrl_dev *pctldev,
> return 0;
> }
>
> +/*
> + * Request a GPIO. If the number of pins for this GPIO group is zero,
> + * then assume that the GPIO is unavailable.
> + */
> +static int msm_request(struct pinctrl_dev *pctldev, unsigned int offset)
These names are awful. Reminds me of the serial driver that has
functions like msm_reset(). But when in Rome this is how it goes
I suppose.
> +{
> + struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
> + const struct msm_pingroup *g;
> +
> + g = &pctrl->soc->groups[offset];
> +
> + return g->npins ? 0 : -ENODEV;
> +}
> +
> static const struct pinmux_ops msm_pinmux_ops = {
> + .request = msm_request,
> .get_functions_count = msm_get_functions_count,
> .get_function_name = msm_get_function_name,
> .get_function_groups = msm_get_function_groups,
> @@ -430,6 +445,14 @@ static int msm_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
>
> g = &pctrl->soc->groups[offset];
>
> + /*
> + * If the GPIO is unavailable, just return error. This is necessary
> + * because the GPIO layer tries to initialize the direction of all
> + * the GPIOs, even the ones that are unavailable.
> + */
> + if (!g->npins)
> + return -ENODEV;
> +
gpiochips also have a request() hook. Can we use that before
initializing direction to make sure the GPIO is accessible?
> val = readl(pctrl->regs + g->ctl_reg);
>
> /* 0 = output, 1 = input */
> @@ -503,7 +531,7 @@ static void msm_gpio_dbg_show_one(struct seq_file *s,
>
> seq_printf(s, " %-8s: %-3s %d", g->name, is_out ? "out" : "in", func);
> seq_printf(s, " %dmA", msm_regval_to_drive(drive));
> - seq_printf(s, " %s", pulls[pull]);
> + seq_printf(s, " %s\n", pulls[pull]);
> }
>
> static void msm_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
> @@ -511,10 +539,8 @@ static void msm_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
> unsigned gpio = chip->base;
> unsigned i;
>
> - for (i = 0; i < chip->ngpio; i++, gpio++) {
> + for (i = 0; i < chip->ngpio; i++, gpio++)
> msm_gpio_dbg_show_one(s, NULL, chip, i, gpio);
> - seq_puts(s, "\n");
> - }
> }
Were these two hunks necessary? Looks like noise.
--
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