On Thu, Dec 29, 2016 at 11:27 PM, Steve Longerbeam
<slongerbeam@xxxxxxxxx> 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_longerbeam@xxxxxxxxxx>
> Cc: Linus Walleij <linus.walleij@xxxxxxxxxx>
> Cc: Alexandre Courbot <gnurou@xxxxxxxxx>
> Cc: linux-gpio@xxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
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
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
