[RFC/PATCH v2 2/2] gpio-rcar: Add DT support
Grant Likely
grant.likely at secretlab.ca
Wed Jun 12 07:49:11 EDT 2013
On Tue, 21 May 2013 13:40:06 +0200, Laurent Pinchart <laurent.pinchart+renesas at ideasonboard.com> wrote:
> Add DT bindings for the gpio-rcar driver and read the device
> configuration from the DT node at probe time if available.
>
> Cc: devicetree-discuss at lists.ozlabs.org
> Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas at ideasonboard.com>
> ---
> .../devicetree/bindings/gpio/renesas,gpio-rcar.txt | 52 +++++++++++++++++
> drivers/gpio/gpio-rcar.c | 66 ++++++++++++++++++----
> 2 files changed, 108 insertions(+), 10 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/gpio/renesas,gpio-rcar.txt
>
> diff --git a/Documentation/devicetree/bindings/gpio/renesas,gpio-rcar.txt b/Documentation/devicetree/bindings/gpio/renesas,gpio-rcar.txt
> new file mode 100644
> index 0000000..46d76a0
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/gpio/renesas,gpio-rcar.txt
> @@ -0,0 +1,52 @@
> +* Renesas R-Car GPIO Controller
> +
> +Required Properties:
> +
> + - compatible: should be one of the following.
> + - "renesas,gpio-r8a7778": for R8A7778 (R-Mobile M1) compatible GPIO controller.
> + - "renesas,gpio-r8a7779": for R8A7779 (R-Car H1) compatible GPIO controller.
> + - "renesas,gpio-r8a7790": for R8A7790 (R-Car H2) compatible GPIO controller.
> + - "renesas,gpio-rcar": for generic R-Car GPIO controller.
> +
> + - reg: Base address and length of each memory resource used by the GPIO
> + controller hardware module.
> +
> + - interrupt-parent: phandle of the parent interrupt controller.
> + - interrupts: Interrupt specifier for the controllers interrupt.
> +
> + - gpio-controller: Marks the device node as a gpio controller.
> + - #gpio-cells: Should be 2. The first cell is the GPIO number and the second
> + cell is used to specify optional parameters as bit flags. Only the GPIO
> + active low flag (bit 0) is currently supported.
> + - gpio-ranges: Range of pins managed by the GPIO controller as a 4-cells
> + tuple using the following syntax.
> +
> + <[phandle of the pin controller node]
> + 0
> + [index of the first pin]
> + [number of pins]>
> +
> +Please refer to gpio.txt in this directory for details of the common GPIO
> +bindings used by client devices.
> +
> +Example: R8A7779 (R-Car H1) GPIO controller nodes
> +
> + gpio0: gpio at ffc40000 {
> + compatible = "renesas,gpio-r8a7779", "renesas,gpio-rcar";
> + reg = <0xffc40000 0x2c>;
> + interrupt-parent = <&gic>;
> + interrupts = <0 141 0x4>;
> + #gpio-cells = <2>;
> + gpio-controller;
> + gpio-ranges = <&pfc 0 0 32>;
> + };
> + ...
> + gpio6: gpio at ffc46000 {
> + compatible = "renesas,gpio-r8a7779", "renesas,gpio-rcar";
> + reg = <0xffc46000 0x2c>;
> + interrupt-parent = <&gic>;
> + interrupts = <0 147 0x4>;
> + #gpio-cells = <2>;
> + gpio-controller;
> + gpio-ranges = <&pfc 0 192 9>;
> + };
> diff --git a/drivers/gpio/gpio-rcar.c b/drivers/gpio/gpio-rcar.c
> index 0f3d647..c153837 100644
> --- a/drivers/gpio/gpio-rcar.c
> +++ b/drivers/gpio/gpio-rcar.c
> @@ -50,6 +50,8 @@ struct gpio_rcar_priv {
> #define EDGLEVEL 0x24
> #define FILONOFF 0x28
>
> +#define RCAR_MAX_GPIO_PER_BANK 32
> +
> static inline u32 gpio_rcar_read(struct gpio_rcar_priv *p, int offs)
> {
> return ioread32(p->base + offs);
> @@ -258,9 +260,39 @@ static struct irq_domain_ops gpio_rcar_irq_domain_ops = {
> .map = gpio_rcar_irq_domain_map,
> };
>
> +static void gpio_rcar_parse_pdata(struct gpio_rcar_priv *p)
> +{
> + struct gpio_rcar_config *pdata = p->pdev->dev.platform_data;
> +#ifdef CONFIG_OF
> + struct device_node *np = p->pdev->dev.of_node;
> + struct of_phandle_args args;
> + int ret;
> +#endif
> +
> + if (pdata)
> + p->config = *pdata;
> +#ifdef CONFIG_OF
> + else if (np) {
Try this:
else if ((IS_ENABLED(CONFIG_OF)) && np) {
It's much better than adding #ifdef blocks to .c files. In v3.11 a bunch
of the OF forward declarations get pulled out from under the #ifdef
block so that you can use the above construct.
> + ret = of_parse_phandle_with_args(np, "gpio-ranges",
> + "#gpio-range-cells", 0, &args);
> + p->config.number_of_pins = ret == 0 && args.args_count == 3
> + ? args.args[2]
> + : RCAR_MAX_GPIO_PER_BANK;
> + p->config.gpio_base = -1;
> + }
> +#endif
> +
> + if (p->config.number_of_pins == 0 ||
> + p->config.number_of_pins > RCAR_MAX_GPIO_PER_BANK) {
> + dev_warn(&p->pdev->dev,
> + "Invalid number of gpio lines %u, using %u\n",
> + p->config.number_of_pins, RCAR_MAX_GPIO_PER_BANK);
> + p->config.number_of_pins = RCAR_MAX_GPIO_PER_BANK;
> + }
> +}
> +
> static int gpio_rcar_probe(struct platform_device *pdev)
> {
> - struct gpio_rcar_config *pdata = pdev->dev.platform_data;
> struct gpio_rcar_priv *p;
> struct resource *io, *irq;
> struct gpio_chip *gpio_chip;
> @@ -275,14 +307,14 @@ static int gpio_rcar_probe(struct platform_device *pdev)
> goto err0;
> }
>
> - /* deal with driver instance configuration */
> - if (pdata)
> - p->config = *pdata;
> -
> p->pdev = pdev;
> - platform_set_drvdata(pdev, p);
> spin_lock_init(&p->lock);
>
> + /* Get device configuration from DT node or platform data. */
> + gpio_rcar_parse_pdata(p);
> +
> + platform_set_drvdata(pdev, p);
> +
> io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
>
> @@ -309,6 +341,7 @@ static int gpio_rcar_probe(struct platform_device *pdev)
> gpio_chip->set = gpio_rcar_set;
> gpio_chip->to_irq = gpio_rcar_to_irq;
> gpio_chip->label = name;
> + gpio_chip->dev = &pdev->dev;
> gpio_chip->owner = THIS_MODULE;
> gpio_chip->base = p->config.gpio_base;
> gpio_chip->ngpio = p->config.number_of_pins;
> @@ -355,10 +388,12 @@ static int gpio_rcar_probe(struct platform_device *pdev)
> p->config.irq_base, ret);
> }
>
> - ret = gpiochip_add_pin_range(gpio_chip, p->config.pctl_name, 0,
> - gpio_chip->base, gpio_chip->ngpio);
> - if (ret < 0)
> - dev_warn(&pdev->dev, "failed to add pin range\n");
> + if (p->config.pctl_name) {
> + ret = gpiochip_add_pin_range(gpio_chip, p->config.pctl_name, 0,
> + gpio_chip->base, gpio_chip->ngpio);
> + if (ret < 0)
> + dev_warn(&pdev->dev, "failed to add pin range\n");
> + }
>
> return 0;
>
> @@ -381,11 +416,22 @@ static int gpio_rcar_remove(struct platform_device *pdev)
> return 0;
> }
>
> +#ifdef CONFIG_OF
> +static const struct of_device_id gpio_rcar_of_table[] = {
> + {
> + .compatible = "renesas,gpio-rcar",
> + },
> +};
> +
> +MODULE_DEVICE_TABLE(of, gpio_rcar_of_table);
> +#endif
> +
> static struct platform_driver gpio_rcar_device_driver = {
> .probe = gpio_rcar_probe,
> .remove = gpio_rcar_remove,
> .driver = {
> .name = "gpio_rcar",
> + .of_match_table = of_match_ptr(gpio_rcar_of_table),
> }
> };
>
> --
> 1.8.1.5
>
> _______________________________________________
> devicetree-discuss mailing list
> devicetree-discuss at lists.ozlabs.org
> https://lists.ozlabs.org/listinfo/devicetree-discuss
--
Grant Likely, B.Sc, P.Eng.
Secret Lab Technologies, Ltd.
More information about the linux-arm-kernel
mailing list