Re: [PATCH] leds-pca9532: Add gpio capability v3 (RESEND)
From: Joachim Eastwood
Date: Sat Feb 12 2011 - 12:50:07 EST
Trying alternate email for Richard Purdie and adding Andrew Morton.
patchwork: https://patchwork.kernel.org/patch/523771/
Patch now also reviewed by Hartley Sweeten. (Thanks Hartley)
On Tue, Feb 1, 2011 at 8:40 PM, Joachim Eastwood <manabian@xxxxxxxxx> wrote:
> Hello,
>
> The patch below allows unused leds on pca9532 to be used as gpio. The
> board I am working on now has no less than 6 pca9532 chips. One chips
> is used for only leds, one has 14 leds and 2 gpio and the rest of the
> chips are gpio only.
>
> There is also one board in mainline which could use this capabilty;
> arch/arm/mach-iop32x/n2100.c
> 232 { .type = PCA9532_TYPE_NONE }, /* power OFF gpio */
> 233 { .type = PCA9532_TYPE_NONE }, /* reset gpio */
>
> This patch defines a new pin type, PCA9532_TYPE_GPIO, and registers a
> gpiochip if any pin has this type set. The gpio will registers all
> chip pins but will filter on gpio_request.
>
> Changes in v3:
> * Fixed direction_output funtion, thanks to H Hartley Sweeten
> * direction_input now calles set_value as direction_output
> * Instructions in Kconfig
>
> Tested on custom ARM board.
>
> -------------------------------------------------------------------
> [leds-pca9532] Add gpio capability
>
> Pins not used for leds can now be used as gpio by setting pin type as
> PCA9532_TYPE_GPIO and defining a gpio_base in platform data.
>
> Signed-off-by: Joachim Eastwood <joachim.eastwood@xxxxxxxxxx>
> Reviewed-by: Wolfram Sang <w.sang@xxxxxxxxxxxxxx>
> ---
> drivers/leds/Kconfig | 10 ++++
> drivers/leds/leds-pca9532.c | 111 ++++++++++++++++++++++++++++++++++++++++-
> include/linux/leds-pca9532.h | 3 +-
> 3 files changed, 120 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
> index 6f190f4..525c517 100644
> --- a/drivers/leds/Kconfig
> +++ b/drivers/leds/Kconfig
> @@ -152,6 +152,16 @@ config LEDS_PCA9532
> LED controller. It is generally only useful
> as a platform driver
>
> +config LEDS_PCA9532_GPIO
> + bool "Enable GPIO support for PCA9532"
> + depends on LEDS_PCA9532
> + depends on GPIOLIB
> + help
> + Allow unused pins on PCA9532 to be used as gpio.
> +
> + To use a pin as gpio pca9532_type in pca9532_platform data needs to
> + set to PCA9532_TYPE_GPIO.
> +
> config LEDS_GPIO
> tristate "LED Support for GPIO connected LEDs"
> depends on LEDS_CLASS
> diff --git a/drivers/leds/leds-pca9532.c b/drivers/leds/leds-pca9532.c
> index afac338..ad008bb 100644
> --- a/drivers/leds/leds-pca9532.c
> +++ b/drivers/leds/leds-pca9532.c
> @@ -19,7 +19,9 @@
> #include <linux/mutex.h>
> #include <linux/workqueue.h>
> #include <linux/leds-pca9532.h>
> +#include <linux/gpio.h>
>
> +#define PCA9532_REG_INPUT(i) ((i)/8)
> #define PCA9532_REG_PSC(i) (0x2+(i)*2)
> #define PCA9532_REG_PWM(i) (0x3+(i)*2)
> #define PCA9532_REG_LS0 0x6
> @@ -34,6 +36,7 @@ struct pca9532_data {
> struct mutex update_lock;
> struct input_dev *idev;
> struct work_struct work;
> + struct gpio_chip gpio;
> u8 pwm[2];
> u8 psc[2];
> };
> @@ -200,16 +203,68 @@ static void pca9532_led_work(struct work_struct *work)
> pca9532_setled(led);
> }
>
> -static void pca9532_destroy_devices(struct pca9532_data *data, int n_devs)
> +#ifdef CONFIG_LEDS_PCA9532_GPIO
> +static int pca9532_gpio_request_pin(struct gpio_chip *gc, unsigned offset)
> +{
> + struct pca9532_data *data = container_of(gc, struct pca9532_data, gpio);
> + struct pca9532_led *led = &data->leds[offset];
> +
> + if (led->type == PCA9532_TYPE_GPIO)
> + return 0;
> +
> + return -EBUSY;
> +}
> +
> +static void pca9532_gpio_set_value(struct gpio_chip *gc, unsigned
> offset, int val)
> +{
> + struct pca9532_data *data = container_of(gc, struct pca9532_data, gpio);
> + struct pca9532_led *led = &data->leds[offset];
> +
> + if (val)
> + led->state = PCA9532_ON;
> + else
> + led->state = PCA9532_OFF;
> +
> + pca9532_setled(led);
> +}
> +
> +static int pca9532_gpio_get_value(struct gpio_chip *gc, unsigned offset)
> +{
> + struct pca9532_data *data = container_of(gc, struct pca9532_data, gpio);
> + unsigned char reg;
> +
> + reg = i2c_smbus_read_byte_data(data->client, PCA9532_REG_INPUT(offset));
> +
> + return !!(reg & (1 << (offset % 8)));
> +}
> +
> +static int pca9532_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
> +{
> + /* To use as input ensure pin is not driven */
> + pca9532_gpio_set_value(gc, offset, 0);
> +
> + return 0;
> +}
> +
> +static int pca9532_gpio_direction_output(struct gpio_chip *gc,
> unsigned offset, int val)
> +{
> + pca9532_gpio_set_value(gc, offset, val);
> +
> + return 0;
> +}
> +#endif /* CONFIG_LEDS_PCA9532_GPIO */
> +
> +static int pca9532_destroy_devices(struct pca9532_data *data, int n_devs)
> {
> int i = n_devs;
>
> if (!data)
> - return;
> + return -EINVAL;
>
> while (--i >= 0) {
> switch (data->leds[i].type) {
> case PCA9532_TYPE_NONE:
> + case PCA9532_TYPE_GPIO:
> break;
> case PCA9532_TYPE_LED:
> led_classdev_unregister(&data->leds[i].ldev);
> @@ -224,12 +279,26 @@ static void pca9532_destroy_devices(struct
> pca9532_data *data, int n_devs)
> break;
> }
> }
> +
> +#ifdef CONFIG_LEDS_PCA9532_GPIO
> + if (data->gpio.dev) {
> + int err = gpiochip_remove(&data->gpio);
> + if (err) {
> + dev_err(&data->client->dev, "%s failed, %d\n",
> + "gpiochip_remove()", err);
> + return err;
> + }
> + }
> +#endif
> +
> + return 0;
> }
>
> static int pca9532_configure(struct i2c_client *client,
> struct pca9532_data *data, struct pca9532_platform_data *pdata)
> {
> int i, err = 0;
> + int gpios = 0;
>
> for (i = 0; i < 2; i++) {
> data->pwm[i] = pdata->pwm[i];
> @@ -249,6 +318,9 @@ static int pca9532_configure(struct i2c_client *client,
> switch (led->type) {
> case PCA9532_TYPE_NONE:
> break;
> + case PCA9532_TYPE_GPIO:
> + gpios++;
> + break;
> case PCA9532_TYPE_LED:
> led->state = pled->state;
> led->name = pled->name;
> @@ -297,6 +369,34 @@ static int pca9532_configure(struct i2c_client *client,
> break;
> }
> }
> +
> +#ifdef CONFIG_LEDS_PCA9532_GPIO
> + if (gpios) {
> + data->gpio.label = "gpio-pca9532";
> + data->gpio.direction_input = pca9532_gpio_direction_input;
> + data->gpio.direction_output = pca9532_gpio_direction_output;
> + data->gpio.set = pca9532_gpio_set_value;
> + data->gpio.get = pca9532_gpio_get_value;
> + data->gpio.request = pca9532_gpio_request_pin;
> + data->gpio.can_sleep = 1;
> + data->gpio.base = pdata->gpio_base;
> + data->gpio.ngpio = 16;
> + data->gpio.dev = &client->dev;
> + data->gpio.owner = THIS_MODULE;
> +
> + err = gpiochip_add(&data->gpio);
> + if (err) {
> + /* Use data->gpio.dev as a flag for freeing gpiochip */
> + data->gpio.dev = NULL;
> + dev_warn(&client->dev, "could not add gpiochip\n");
> + } else {
> + dev_info(&client->dev, "gpios %i...%i\n",
> + data->gpio.base, data->gpio.base +
> + data->gpio.ngpio - 1);
> + }
> + }
> +#endif
> +
> return 0;
>
> exit:
> @@ -337,7 +437,12 @@ static int pca9532_probe(struct i2c_client *client,
> static int pca9532_remove(struct i2c_client *client)
> {
> struct pca9532_data *data = i2c_get_clientdata(client);
> - pca9532_destroy_devices(data, 16);
> + int err;
> +
> + err = pca9532_destroy_devices(data, 16);
> + if (err)
> + return err;
> +
> kfree(data);
> return 0;
> }
> diff --git a/include/linux/leds-pca9532.h b/include/linux/leds-pca9532.h
> index f158eb1..b8d6fff 100644
> --- a/include/linux/leds-pca9532.h
> +++ b/include/linux/leds-pca9532.h
> @@ -25,7 +25,7 @@ enum pca9532_state {
> };
>
> enum pca9532_type { PCA9532_TYPE_NONE, PCA9532_TYPE_LED,
> - PCA9532_TYPE_N2100_BEEP };
> + PCA9532_TYPE_N2100_BEEP, PCA9532_TYPE_GPIO };
>
> struct pca9532_led {
> u8 id;
> @@ -41,6 +41,7 @@ struct pca9532_platform_data {
> struct pca9532_led leds[16];
> u8 pwm[2];
> u8 psc[2];
> + int gpio_base;
> };
>
> #endif /* __LINUX_PCA9532_H */
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/