Hi Krzysztof Kozlowski,
Thanks for the patch.
> -----Original Message-----
> From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
> Sent: Friday, January 5, 2024 3:59 PM
> Subject: [PATCH v2 1/4] reset: gpio: Add GPIO-based reset controller
>
> Add a simple driver to control GPIO-based resets using the reset
> controller API for the cases when the GPIOs are shared and reset should be
> coordinated. The driver is expected to be used by reset core framework
> for ad-hoc reset controllers.
>
> Cc: Bartosz Golaszewski <brgl@xxxxxxxx>
> Cc: Sean Anderson <sean.anderson@xxxxxxxx>
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
> ---
> MAINTAINERS | 5 ++
> drivers/reset/Kconfig | 9 +++
> drivers/reset/Makefile | 1 +
> drivers/reset/reset-gpio.c | 121 +++++++++++++++++++++++++++++++++++++
> 4 files changed, 136 insertions(+)
> create mode 100644 drivers/reset/reset-gpio.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 7fe27cd60e1b..a0fbd4814bc7 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -8866,6 +8866,11 @@ F: Documentation/i2c/muxes/i2c-mux-gpio.rst
> F: drivers/i2c/muxes/i2c-mux-gpio.c
> F: include/linux/platform_data/i2c-mux-gpio.h
>
> +GENERIC GPIO RESET DRIVER
> +M: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
> +S: Maintained
> +F: drivers/reset/reset-gpio.c
> +
> GENERIC HDLC (WAN) DRIVERS
> M: Krzysztof Halasa <khc@xxxxxxxxx>
> S: Maintained
> diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig index
> ccd59ddd7610..bb1b5a326eb7 100644
> --- a/drivers/reset/Kconfig
> +++ b/drivers/reset/Kconfig
> @@ -66,6 +66,15 @@ config RESET_BRCMSTB_RESCAL
> This enables the RESCAL reset controller for SATA, PCIe0, or PCIe1
> on
> BCM7216.
>
> +config RESET_GPIO
> + tristate "GPIO reset controller"
> + help
> + This enables a generic reset controller for resets attached via
> + GPIOs. Typically for OF platforms this driver expects "reset-
> gpios"
> + property.
> +
> + If compiled as module, it will be called reset-gpio.
> +
> config RESET_HSDK
> bool "Synopsys HSDK Reset Driver"
> depends on HAS_IOMEM
> diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile index
> 8270da8a4baa..fd8b49fa46fc 100644
> --- a/drivers/reset/Makefile
> +++ b/drivers/reset/Makefile
> @@ -11,6 +11,7 @@ obj-$(CONFIG_RESET_BCM6345) += reset-bcm6345.o
> obj-$(CONFIG_RESET_BERLIN) += reset-berlin.o
> obj-$(CONFIG_RESET_BRCMSTB) += reset-brcmstb.o
> obj-$(CONFIG_RESET_BRCMSTB_RESCAL) += reset-brcmstb-rescal.o
> +obj-$(CONFIG_RESET_GPIO) += reset-gpio.o
> obj-$(CONFIG_RESET_HSDK) += reset-hsdk.o
> obj-$(CONFIG_RESET_IMX7) += reset-imx7.o
> obj-$(CONFIG_RESET_INTEL_GW) += reset-intel-gw.o diff --git
> a/drivers/reset/reset-gpio.c b/drivers/reset/reset-gpio.c new file mode
> 100644 index 000000000000..cf0a867cbc5f
> --- /dev/null
> +++ b/drivers/reset/reset-gpio.c
> @@ -0,0 +1,121 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +#include <linux/gpio/consumer.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/reset-controller.h>
> +
> +struct reset_gpio_priv {
> + struct reset_controller_dev rc;
> + struct gpio_desc *reset;
> +};
> +
> +static inline struct reset_gpio_priv
> +*rc_to_reset_gpio(struct reset_controller_dev *rc) {
> + return container_of(rc, struct reset_gpio_priv, rc); }
> +
> +static int reset_gpio_assert(struct reset_controller_dev *rc, unsigned
> +long id) {
> + struct reset_gpio_priv *priv = rc_to_reset_gpio(rc);
> +
> + gpiod_set_value_cansleep(priv->reset, 1);
> +
> + return 0;
> +}
> +
> +static int reset_gpio_deassert(struct reset_controller_dev *rc,
> + unsigned long id)
> +{
> + struct reset_gpio_priv *priv = rc_to_reset_gpio(rc);
> +
> + gpiod_set_value_cansleep(priv->reset, 0);
> +
> + return 0;
> +}
> +
> +static int reset_gpio_status(struct reset_controller_dev *rc, unsigned
> +long id) {
> + struct reset_gpio_priv *priv = rc_to_reset_gpio(rc);
> +
> + return gpiod_get_value_cansleep(priv->reset);
> +}
> +
> +static const struct reset_control_ops reset_gpio_ops = {
> + .assert = reset_gpio_assert,
> + .deassert = reset_gpio_deassert,
> + .status = reset_gpio_status,
> +};
> +
> +static void reset_gpio_of_args_put(void *data) {
> + of_node_put(data);
> +}
> +
> +static int reset_gpio_probe(struct platform_device *pdev) {
> + struct device *dev = &pdev->dev;
> + struct device_node **platdata = dev_get_platdata(dev);
> + struct of_phandle_args gpio_args;
> + struct reset_gpio_priv *priv;
> + int ret;
> +
> + if (!platdata || !*platdata)
Maybe, if (!(platdata && *platdata)) which reduces 1 inversion operation.
Cheers,
Biju
