On Thu, Dec 29, 2016 at 11:27 PM, Steve Longerbeam
<slongerb...@gmail.com> wrote:
> Add optional reset-gpios pin control. If present, de-assert the
> specified reset gpio pin to bring the chip out of reset.
>
> Signed-off-by: Steve Longerbeam <steve_longerb...@mentor.com>
> Cc: Linus Walleij <linus.wall...@linaro.org>
> Cc: Alexandre Courbot <gnu...@gmail.com>
> Cc: linux-g...@vger.kernel.org
> Cc: linux-ker...@vger.kernel.org
This seems like a separate patch from the other 19 patches so please send it
separately so I can handle logistics easier in the future.
> @@ -133,6 +134,7 @@ struct pca953x_chip {
> const char *const *names;
> unsigned long driver_data;
> struct regulator *regulator;
> + struct gpio_desc *reset_gpio;
Why do you even keep this around in the device state container?
As you only use it in the probe() function, use a local variable.
The descriptor will be free():ed by the devm infrastructure anyways.
> + /* see if we need to de-assert a reset pin */
> + chip->reset_gpio = devm_gpiod_get_optional(&client->dev,
> + "reset",
> + GPIOD_OUT_LOW);
> + if (IS_ERR(chip->reset_gpio)) {
> + dev_err(&client->dev, "request for reset pin
> failed\n");
> + return PTR_ERR(chip->reset_gpio);
> + }
Nice.
> + if (chip->reset_gpio) {
> + /* bring chip out of reset */
> + dev_info(&client->dev, "releasing reset\n");
> + gpiod_set_value(chip->reset_gpio, 0);
> + }
Is this really needed given that you set it low in the
devm_gpiod_get_optional()?
Yours,
Linus Walleij
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