[PATCH v5] gpio: Device tree support for LPC32xx
Jean-Christophe PLAGNIOL-VILLARD
plagnioj at jcrosoft.com
Sat Apr 21 04:03:21 EDT 2012
On 09:55 Sat 21 Apr , Roland Stigge wrote:
> This patch adds device tree support for gpio-lpc32xx.c
>
> Signed-off-by: Roland Stigge <stigge at antcom.de>
>
> ---
>
> Applies to v3.4-rc3
>
> Changes since last version:
> * Typo fix in documentation
> * Changed "compatible" strings to non-wildcard versions
> * Removed Arnd Bergmann's "Reviewed-by:" due to above change
>
> Documentation/devicetree/bindings/gpio/gpio_lpc32xx.txt | 66 ++++++++++++++++
> arch/arm/mach-lpc32xx/include/mach/gpio.h | 9 +-
> drivers/gpio/gpio-lpc32xx.c | 55 ++++++++++++-
> 3 files changed, 127 insertions(+), 3 deletions(-)
>
> --- /dev/null
> +++ linux-2.6/Documentation/devicetree/bindings/gpio/gpio_lpc32xx.txt
> @@ -0,0 +1,66 @@
> +NXP LPC32xx SoC GPIO controller
> +
> +Required properties:
> +- compatible: must be "nxp,lpc3220-gpio", "nxp,lpc3230-gpio", "nxp,lpc3240-gpio"
> + or "nxp,lpc3250-gpio"
same comment as on the ADC you don't need to list all
just put the first soc where this IP was used
> +- reg: Physical base address and length of the controller's registers.
> +- #address-cells: Always 1, for indexing of the subnodes (GPIO groups of the
> + SoC)
> +- #size-cells: Always 0
> +
> +Required properties of sub-nodes which describe the GPIO groups of LPC32xx:
> +- gpio-controller: Marks the device node as a GPIO controller.
> +- #gpio-cells: Should be two. The first cell is the pin number and the
> + second cell is used to specify optional parameters:
> + - bit 0 specifies polarity (0 for normal, 1 for inverted)
> +- reg: Index of the GPIO group
> +
> +Optional properties of sub-nodes which describe the GPIO groups of LPC32xx:
> +- status: Set to "disabled" if you don't use the respective GPIO group
> + of the LPC32xx SoC
> +
> +Example:
> +
> + gpio: gpio at 40028000 {
> + compatible = "nxp,lpc3250-gpio";
> + reg = <0x40028000 0x1000>;
> + /* create a private address space for enumeration */
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + gpio_p0: gpio-bank at 0 {
> + gpio-controller;
> + #gpio-cells = <2>;
> + reg = <0>;
> + };
> +
> + gpio_p1: gpio-bank at 1 {
> + gpio-controller;
> + #gpio-cells = <2>;
> + reg = <1>;
> + };
> +
> + gpio_p2: gpio-bank at 2 {
> + gpio-controller;
> + #gpio-cells = <2>;
> + reg = <2>;
> + };
> +
> + gpio_p3: gpio-bank at 3 {
> + gpio-controller;
> + #gpio-cells = <2>;
> + reg = <3>;
> + };
> +
> + gpi_p3: gpio-bank at 4 {
> + gpio-controller;
> + #gpio-cells = <2>;
> + reg = <4>;
> + };
> +
> + gpo_p3: gpio-bank at 5 {
> + gpio-controller;
> + #gpio-cells = <2>;
> + reg = <5>;
> + };
> + };
> --- linux-2.6.orig/arch/arm/mach-lpc32xx/include/mach/gpio.h
> +++ linux-2.6/arch/arm/mach-lpc32xx/include/mach/gpio.h
> @@ -1 +1,8 @@
> -/* empty */
> +#ifndef __MACH_GPIO_H
> +#define __MACH_GPIO_H
> +
> +#include "gpio-lpc32xx.h"
> +
> +#define ARCH_NR_GPIOS (LPC32XX_GPO_P3_GRP + LPC32XX_GPO_P3_MAX)
> +
> +#endif /* __MACH_GPIO_H */
> --- linux-2.6.orig/drivers/gpio/gpio-lpc32xx.c
> +++ linux-2.6/drivers/gpio/gpio-lpc32xx.c
> @@ -21,6 +21,9 @@
> #include <linux/io.h>
> #include <linux/errno.h>
> #include <linux/gpio.h>
> +#include <linux/of_gpio.h>
> +#include <linux/platform_device.h>
> +#include <linux/module.h>
>
> #include <mach/hardware.h>
> #include <mach/platform.h>
> @@ -454,10 +457,58 @@ static struct lpc32xx_gpio_chip lpc32xx_
> },
> };
>
> +/* Empty now, can be removed later when mach-lpc32xx is finally switched over
> + * to DT support
> + */
> void __init lpc32xx_gpio_init(void)
> {
> +}
> +
> +static int __devinit lpc32xx_gpio_probe(struct platform_device *pdev)
> +{
> + struct device_node *node;
> int i;
>
> - for (i = 0; i < ARRAY_SIZE(lpc32xx_gpiochip); i++)
> - gpiochip_add(&lpc32xx_gpiochip[i].chip);
> + if (pdev->dev.of_node) {
> + for_each_child_of_node(pdev->dev.of_node, node) {
> + if (of_device_is_available(node)) {
> + u32 index;
> + struct gpio_chip *chip;
> + if (of_property_read_u32(node,
> + "reg", &index) < 0)
> + continue;
> + if (index >= ARRAY_SIZE(lpc32xx_gpiochip))
> + continue;
> + chip = &lpc32xx_gpiochip[index].chip;
> + chip->of_node = of_node_get(node);
> + gpiochip_add(chip);
split this in an toher function so it's more readble
Best Regards,
J.
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