On Mon, Jan 30, 2023 at 02:09:47PM +0100, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@xxxxxxxx>
>
> The gpio usage in the function is fairly straightforward,
> but the normal gpiod_get() interface cannot be used here
> since the gpio is referenced by a child node of the device.
>
> Using devm_fwnode_gpiod_get_index() is the best alternative
> here.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
One topic to discuss below (but I'm fine with this version).
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
> .../st/sti/c8sectpfe/c8sectpfe-core.c | 30 ++++++++-----------
> .../st/sti/c8sectpfe/c8sectpfe-core.h | 2 +-
> 2 files changed, 13 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/media/platform/st/sti/c8sectpfe/c8sectpfe-core.c b/drivers/media/platform/st/sti/c8sectpfe/c8sectpfe-core.c
> index c38b62d4f1ae..86a2c77c5471 100644
> --- a/drivers/media/platform/st/sti/c8sectpfe/c8sectpfe-core.c
> +++ b/drivers/media/platform/st/sti/c8sectpfe/c8sectpfe-core.c
> @@ -22,7 +22,7 @@
> #include <linux/interrupt.h>
> #include <linux/io.h>
> #include <linux/module.h>
> -#include <linux/of_gpio.h>
> +#include <linux/gpio/consumer.h>
> #include <linux/of_platform.h>
> #include <linux/pinctrl/consumer.h>
> #include <linux/pinctrl/pinctrl.h>
> @@ -812,30 +812,24 @@ static int c8sectpfe_probe(struct platform_device *pdev)
> }
> of_node_put(i2c_bus);
>
> - tsin->rst_gpio = of_get_named_gpio(child, "reset-gpios", 0);
> -
> - ret = gpio_is_valid(tsin->rst_gpio);
> - if (!ret) {
> - dev_err(dev,
> - "reset gpio for tsin%d not valid (gpio=%d)\n",
> - tsin->tsin_id, tsin->rst_gpio);
> - ret = -EINVAL;
> - goto err_node_put;
> - }
> -
> - ret = devm_gpio_request_one(dev, tsin->rst_gpio,
> - GPIOF_OUT_INIT_LOW, "NIM reset");
> + tsin->rst_gpio = devm_fwnode_gpiod_get_index(dev,
> + of_node_to_fwnode(child),
> + "reset-gpios",
> + 0, GPIOD_OUT_LOW,
> + "NIM reset");
> + ret = PTR_ERR_OR_ZERO(tsin->rst_gpio);
> if (ret && ret != -EBUSY) {
> - dev_err(dev, "Can't request tsin%d reset gpio\n"
> - , fei->channel_data[index]->tsin_id);
> + dev_err_probe(dev, ret,
> + "reset gpio for tsin%d not valid\n",
> + tsin->tsin_id);
> goto err_node_put;
> }
>
> if (!ret) {
Can be
if (IS_ERR() && PTR_ERR() != -EBUSY) {
ret = dev_err_probe(dev, PTR_ERR(), ...);
...
}
if (!IS_ERR())
(Up to you)
But -EBUSY check seems strange to me. What was the motivation behind?
(As far as I can read the code the possibility to get this if and only
if we have requested GPIO too early at initcall level. Would it be
ever a possibility to get it in real life?)
> /* toggle reset lines */
> - gpio_direction_output(tsin->rst_gpio, 0);
> + gpiod_direction_output(tsin->rst_gpio, 0);
> usleep_range(3500, 5000);
> - gpio_direction_output(tsin->rst_gpio, 1);
> + gpiod_direction_output(tsin->rst_gpio, 1);
> usleep_range(3000, 5000);
> }
>
> diff --git a/drivers/media/platform/st/sti/c8sectpfe/c8sectpfe-core.h b/drivers/media/platform/st/sti/c8sectpfe/c8sectpfe-core.h
> index c9d6021904cd..f2a6991e064e 100644
> --- a/drivers/media/platform/st/sti/c8sectpfe/c8sectpfe-core.h
> +++ b/drivers/media/platform/st/sti/c8sectpfe/c8sectpfe-core.h
> @@ -25,7 +25,7 @@ struct channel_info {
> int i2c;
> int dvb_card;
>
> - int rst_gpio;
> + struct gpio_desc *rst_gpio;
>
> struct i2c_adapter *i2c_adapter;
> struct i2c_adapter *tuner_i2c;
> --
> 2.39.0
>
--
With Best Regards,
Andy Shevchenko
