Re: [PATCH v2 3/4] PCI: imx6: Convert to agnostic GPIO API

[Frank Li]

On Tue, Apr 23, 2024 at 08:19:06PM +0300, Andy Shevchenko wrote:
> The of_gpio.h is going to be removed. In preparation of that convert
> the driver to the agnostic API.
> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> ---
>  drivers/pci/controller/dwc/pci-imx6.c | 37 ++++++++++-----------------
>  1 file changed, 14 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index 917c69edee1d..d620f1e1a43c 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -11,14 +11,13 @@
>  #include <linux/bitfield.h>
>  #include <linux/clk.h>
>  #include <linux/delay.h>
> -#include <linux/gpio.h>
> +#include <linux/gpio/consumer.h>
>  #include <linux/kernel.h>
>  #include <linux/mfd/syscon.h>
>  #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
>  #include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
>  #include <linux/module.h>
>  #include <linux/of.h>
> -#include <linux/of_gpio.h>
>  #include <linux/of_address.h>
>  #include <linux/pci.h>
>  #include <linux/platform_device.h>
> @@ -107,7 +106,7 @@ struct imx6_pcie_drvdata {
>  
>  struct imx6_pcie {
>  	struct dw_pcie		*pci;
> -	int			reset_gpio;
> +	struct gpio_desc	*reset_gpiod;
>  	bool			gpio_active_high;
>  	bool			link_is_up;
>  	struct clk_bulk_data	clks[IMX6_PCIE_MAX_CLKS];
> @@ -721,9 +720,8 @@ static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
>  	}
>  
>  	/* Some boards don't have PCIe reset GPIO. */
> -	if (gpio_is_valid(imx6_pcie->reset_gpio))
> -		gpio_set_value_cansleep(imx6_pcie->reset_gpio,
> -					imx6_pcie->gpio_active_high);
> +	gpiod_set_raw_value_cansleep(imx6_pcie->reset_gpiod,
> +				     imx6_pcie->gpio_active_high);
>  }
>  
>  static int imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
> @@ -771,10 +769,10 @@ static int imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
>  	}
>  
>  	/* Some boards don't have PCIe reset GPIO. */
> -	if (gpio_is_valid(imx6_pcie->reset_gpio)) {
> +	if (imx6_pcie->reset_gpiod) {
>  		msleep(100);
> -		gpio_set_value_cansleep(imx6_pcie->reset_gpio,
> -					!imx6_pcie->gpio_active_high);
> +		gpiod_set_raw_value_cansleep(imx6_pcie->reset_gpiod,
> +					     !imx6_pcie->gpio_active_high);
>  		/* Wait for 100ms after PERST# deassertion (PCIe r5.0, 6.6.1) */
>  		msleep(100);
>  	}
> @@ -1285,22 +1283,15 @@ static int imx6_pcie_probe(struct platform_device *pdev)
>  		return PTR_ERR(pci->dbi_base);
>  
>  	/* Fetch GPIOs */
> -	imx6_pcie->reset_gpio = of_get_named_gpio(node, "reset-gpio", 0);
>  	imx6_pcie->gpio_active_high = of_property_read_bool(node,
>  						"reset-gpio-active-high");
> -	if (gpio_is_valid(imx6_pcie->reset_gpio)) {
> -		ret = devm_gpio_request_one(dev, imx6_pcie->reset_gpio,
> -				imx6_pcie->gpio_active_high ?
> -					GPIOF_OUT_INIT_HIGH :
> -					GPIOF_OUT_INIT_LOW,
> -				"PCIe reset");
> -		if (ret) {
> -			dev_err(dev, "unable to get reset gpio\n");
> -			return ret;
> -		}
> -	} else if (imx6_pcie->reset_gpio == -EPROBE_DEFER) {
> -		return imx6_pcie->reset_gpio;
> -	}
> +	imx6_pcie->reset_gpiod =
> +		devm_gpiod_get_optional(dev, "reset",
> +			imx6_pcie->gpio_active_high ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW);
> +	if (IS_ERR(imx6_pcie->reset_gpiod))
> +		return dev_err_probe(dev, PTR_ERR(imx6_pcie->reset_gpiod),
> +				     "unable to get reset gpio\n");

Small problem here. err message "unable to get reset gpio\n" will print
when -EPROBE_DEFER happen. EPROBE_DEFER is quite common when use i2c
expand gpio chip.

Frank

> +	gpiod_set_consumer_name(imx6_pcie->reset_gpiod, "PCIe reset");
>  
>  	if (imx6_pcie->drvdata->clks_cnt >= IMX6_PCIE_MAX_CLKS)
>  		return dev_err_probe(dev, -ENOMEM, "clks_cnt is too big\n");
> -- 
> 2.43.0.rc1.1336.g36b5255a03ac
>