[RFC/PATCH v2 2/2] gpio-rcar: Add DT support
Laurent Pinchart
laurent.pinchart+renesas at ideasonboard.com
Tue May 21 07:40:06 EDT 2013
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) {
+ 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
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