On Thu, Jun 23, 2011 at 4:04 AM, David Jander <david@xxxxxxxxxxx> wrote:
> This patch enables fetching configuration data which is normally provided via
> platform_data from the device-tree instead.
> If the device is configured from device-tree data, the platform_data struct
> is not used, and button data needs to be allocated dynamically.
> Big part of this patch deals with confining pdata usage to the probe function,
> to make this possible.
>
> Signed-off-by: David Jander <david@xxxxxxxxxxx>
> ---
> .../devicetree/bindings/gpio/gpio_keys.txt | 37 +++++
> drivers/input/keyboard/gpio_keys.c | 146 ++++++++++++++++++--
> 2 files changed, 168 insertions(+), 15 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/gpio/gpio_keys.txt
>
> diff --git a/Documentation/devicetree/bindings/gpio/gpio_keys.txt b/Documentation/devicetree/bindings/gpio/gpio_keys.txt
> new file mode 100644
> index 0000000..a0fed97
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/gpio/gpio_keys.txt
> @@ -0,0 +1,37 @@
> +Device-Tree bindings for input/gpio_keys.c keyboard driver
> +
> +Required properties:
> + - compatible = "gpio-keys";
> +
> +Optional properties:
> + - autorepeat: Boolean, Enable auto repeat feature of Linux input
> + subsystem.
> +
> +Each button (key) is represented as a sub-node of "gpio-keys":
> +Subnode properties:
> +
> + - gpios: OF devcie-tree gpio specificatin.
> + - label: Descriptive name of the key.
> + - linux,code: Keycode to emit.
The fact that this is the Linux internal keycode definitions still
makes me nervous. Is there no existing standard for keycodes emitted
by keyboard devices?
> +
> +Optional subnode-properties:
> + - linux,input-type: Specify event type this button/key generates.
> + Default if unspecified is <1> == EV_KEY.
> + - debounce-interval: Debouncing interval time in milliseconds.
> + Default if unspecified is 5.
> + - gpio-key,wakeup: Boolean, button can wake-up the system.
> +
> +Example nodes:
> +
> + gpio_keys {
> + compatible = "gpio-keys";
> + #address-cells = <1>;
> + #size-cells = <0>;
> + autorepeat;
> + button@21 {
> + label = "GPIO Key UP";
> + linux,code = <103>;
> + gpios = <&gpio1 0 1>;
> + };
> + ...
> +
> diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c
> index 6e6145b..2db7db2 100644
> --- a/drivers/input/keyboard/gpio_keys.c
> +++ b/drivers/input/keyboard/gpio_keys.c
> @@ -3,6 +3,9 @@
> *
> * Copyright 2005 Phil Blundell
> *
> + * Added OF support:
> + * Copyright 2010, 2011 David Jander <david@xxxxxxxxxxx>
> + *
> * This program is free software; you can redistribute it and/or modify
> * it under the terms of the GNU General Public License version 2 as
> * published by the Free Software Foundation.
> @@ -25,6 +28,8 @@
> #include <linux/gpio_keys.h>
> #include <linux/workqueue.h>
> #include <linux/gpio.h>
> +#include <linux/of_platform.h>
> +#include <linux/of_gpio.h>
>
> struct gpio_button_data {
> struct gpio_keys_button *button;
> @@ -445,15 +450,111 @@ static void gpio_keys_close(struct input_dev *input)
> ddata->disable(input->dev.parent);
> }
>
> +/*
> + * Handlers for alternative sources of platform_data
> + */
> +#ifdef CONFIG_OF
> +/*
> + * Translate OpenFirmware node properties into platform_data
> + */
> +static int gpio_keys_get_devtree_pdata(struct device *dev,
> + struct gpio_keys_platform_data *pdata)
> +{
> + struct device_node *node, *pp;
> + int i;
> + struct gpio_keys_button *buttons;
> + const u32 *reg;
> + int len;
> +
> + node = dev->of_node;
> + if (node == NULL)
> + return -ENODEV;
> +
> + memset(pdata, 0, sizeof *pdata);
> +
> + pdata->rep = !!of_get_property(node, "autorepeat", &len);
> +
> + /* First count the subnodes */
> + pdata->nbuttons = 0;
> + pp = NULL;
> + while ((pp = of_get_next_child(node, pp)))
> + pdata->nbuttons++;
> +
> + if (pdata->nbuttons == 0)
> + return -ENODEV;
> +
> + buttons = kzalloc(pdata->nbuttons * (sizeof *buttons), GFP_KERNEL);
> + if (!buttons)
> + return -ENODEV;
> +
> + pp = NULL;
> + i = 0;
> + while ((pp = of_get_next_child(node, pp))) {
> + const char *lbl;
> + enum of_gpio_flags flags;
> +
> + if (!of_find_property(pp, "gpios", NULL)) {
> + pdata->nbuttons--;
> + dev_warn(dev, "Found button without gpios\n");
> + continue;
> + }
> + buttons[i].gpio = of_get_gpio_flags(pp, 0, &flags);
> + buttons[i].active_low = !!(flags & OF_GPIO_ACTIVE_LOW);
> +
> + reg = of_get_property(pp, "linux,code", &len);
> + if (!reg) {
> + dev_err(dev, "Button without keycode: 0x%x\n", buttons[i].gpio);
> + goto out_fail;
> + }
> + buttons[i].code = be32_to_cpup(reg);
> +
> + lbl = of_get_property(pp, "label", &len);
> + buttons[i].desc = (char *)lbl;
> +
> + reg = of_get_property(pp, "linux,input-type", &len);
> + buttons[i].type = reg ? be32_to_cpup(reg) : EV_KEY;
> +
> + buttons[i].wakeup = !!of_get_property(pp, "gpio-key,wakeup", NULL);
> +
> + reg = of_get_property(pp, "debounce-interval", &len);
> + buttons[i].debounce_interval = reg ? be32_to_cpup(reg) : 5;
> +
> + i++;
> + }
> +
> + pdata->buttons = buttons;
> +
> + return 0;
> +
> +out_fail:
> + kfree(buttons);
> + return -ENODEV;
> +}
> +#else
> +static int gpio_keys_get_devtree_pdata(struct device *dev,
> + struct gpio_keys_platform_data *altp)
> +{
> + return -ENODEV;
> +}
> +#endif
> +
> static int __devinit gpio_keys_probe(struct platform_device *pdev)
> {
> struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
> struct gpio_keys_drvdata *ddata;
> struct device *dev = &pdev->dev;
> + struct gpio_keys_platform_data alt_pdata;
> struct input_dev *input;
> int i, error;
> int wakeup = 0;
>
> + if (!pdata) {
> + error = gpio_keys_get_devtree_pdata(dev, &alt_pdata);
> + if (error)
> + return error;
> + pdata = &alt_pdata;
> + }
> +
> ddata = kzalloc(sizeof(struct gpio_keys_drvdata) +
> pdata->nbuttons * sizeof(struct gpio_button_data),
> GFP_KERNEL);
> @@ -550,7 +651,6 @@ static int __devinit gpio_keys_probe(struct platform_device *pdev)
>
> static int __devexit gpio_keys_remove(struct platform_device *pdev)
> {
> - struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
> struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev);
> struct input_dev *input = ddata->input;
> int i;
> @@ -559,31 +659,42 @@ static int __devexit gpio_keys_remove(struct platform_device *pdev)
>
> device_init_wakeup(&pdev->dev, 0);
>
> - for (i = 0; i < pdata->nbuttons; i++) {
> - int irq = gpio_to_irq(pdata->buttons[i].gpio);
> + for (i = 0; i < ddata->n_buttons; i++) {
> + int irq = gpio_to_irq(ddata->data[i].button->gpio);
> free_irq(irq, &ddata->data[i]);
> if (ddata->data[i].timer_debounce)
> del_timer_sync(&ddata->data[i].timer);
> cancel_work_sync(&ddata->data[i].work);
> - gpio_free(pdata->buttons[i].gpio);
> + gpio_free(ddata->data[i].button->gpio);
> }
>
> + /*
> + * If we had no platform_data, we allocated buttons dynamically, and
> + * must free them here. ddata->data[0].button is the pointer to the
> + * beginning of the allocated array.
> + */
> + if (!pdev->dev.platform_data)
> + kfree(ddata->data[0].button);
> +
> input_unregister_device(input);
>
> return 0;
> }
>
> +static struct of_device_id gpio_keys_of_match[] = {
> + { .compatible = "gpio-keys", },
> + {},
> +};
This gpio_keys_of_match[]...
> @@ -622,6 +731,12 @@ static const struct dev_pm_ops gpio_keys_pm_ops = {
> };
> #endif
>
> +#ifdef CONFIG_OF
> +MODULE_DEVICE_TABLE(of, gpio_keys_of_match);
> +#else
> +#define gpio_keys_of_match NULL
> +#endif
...belongs inside this #ifdef CONFIG_OF block.
In fact, there should only need to be one #ifdef CONFIG_OF/#else block
in this .c file.
g.
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