Re: [PATCH v3] leds: Add DT support for leds-pca9532

[Bryan Wu <cooloney@gmail.com>]

On Wed, Sep 10, 2014 at 8:29 AM, Roland Stigge <stigge@antcom.de> wrote:
> This patch adds DT support for leds-pca9532.
>
> Signed-off-by: Roland Stigge <stigge@antcom.de>
>
> ---
> Applies to v3.17-rc4
>
>  v3: Removed superfluous whitespace
>  v2: Removed #ifdef statements
>
>  Documentation/devicetree/bindings/leds/leds-pca9532.txt |   43 ++++++++++++++
>  drivers/leds/leds-pca9532.c                             |   47 ++++++++++++++++
>  2 files changed, 90 insertions(+)
>
> --- /dev/null
> +++ linux-2.6/Documentation/devicetree/bindings/leds/leds-pca9532.txt
> @@ -0,0 +1,43 @@
> +NXP PCA9532 LED (incl. GPIO) controller
> +
> +Required properties:
> +- compatible: must be "nxp,pca9532"
> +- reg: I2C address
> +- gpio-controller: Marks the device node as a GPIO controller.
> +- #gpio-cells: Should be 2:
> +   1) pin number
> +   2) optional parameters:
> +      - bit 0 specifies polarity (0 for normal, 1 for inverted)
> +- nxp,typecodes: groups of 2 bits for each of the 16 pins:
> +  0: None
> +  1: LED
> +  2: Beep
> +  3: GPIO
> +- nxp,statecodes: groups of 2 bits for each of the 16 pins:
> +  0: off
> +  1: on
> +  2: pwm0
> +  3: pwm1
> +
> +Optional properties:
> +- nxp,psc: array of 2 numbers: PSC values for the two PWM channels (see datasheet)
> +- nxp,pwm: array of 2 numbers: PWM values for the two PWM channels (see datasheet)
> +
> +Example:
> +
> +       pca9532: pca9532@60 {
> +               compatible = "nxp,pca9532";
> +               gpio-controller;
> +               #gpio-cells = <2>;
> +               nxp,typecodes = <0xffffffff>;
> +               nxp,statecodes = <0x00000000>;
> +               reg = <0x60>;
> +       };
> +
> +       sd@20098000 {
> +               wp-gpios = <&pca9532 5 0>;
> +               cd-gpios = <&pca9532 4 0>;
> +               cd-inverted;
> +               bus-width = <4>;
> +               status = "okay";
> +       };
> --- linux-2.6.orig/drivers/leds/leds-pca9532.c
> +++ linux-2.6/drivers/leds/leds-pca9532.c
> @@ -21,6 +21,7 @@
>  #include <linux/workqueue.h>
>  #include <linux/leds-pca9532.h>
>  #include <linux/gpio.h>
> +#include <linux/of.h>
>
>  /* m =  num_leds*/
>  #define PCA9532_REG_INPUT(i)   ((i) >> 3)
> @@ -442,6 +443,43 @@ exit:
>         return err;
>  }
>
> +static struct pca9532_platform_data *pca9532_parse_dt(struct device *dev)
> +{
> +       struct device_node *np = dev->of_node;
> +       struct pca9532_platform_data *pca9532_pdata;
> +       u32 typecodes, statecodes;
> +       u32 pwm[2];
> +       u32 psc[2];
> +       int i;
> +
> +       pca9532_pdata = devm_kzalloc(dev, sizeof(*pca9532_pdata), GFP_KERNEL);
> +       if (!pca9532_pdata)
> +               return NULL;
> +
> +       if (!of_property_read_u32(np, "nxp,typecodes", &typecodes)) {

Can we do some error check here and print out warning/error message?
If this fails (unlikely), will we still continue?

-Bryan

> +               for (i = 0; i < 16; i++)
> +                       pca9532_pdata->leds[i].type =
> +                               (typecodes >> (2 * i)) & 0x3;
> +       }
> +       if (!of_property_read_u32(np, "nxp,statecodes", &statecodes)) {
> +               for (i = 0; i < 16; i++)
> +                       pca9532_pdata->leds[i].state =
> +                               (statecodes >> (2 * i)) & 0x3;
> +       }
> +       if (!of_property_read_u32_array(np, "nxp,pwm", &pwm[0], 2)) {
> +               for (i = 0; i < 2; i++)
> +                       pca9532_pdata->pwm[i] = pwm[i];
> +       }
> +       if (!of_property_read_u32_array(np, "nxp,psc", &psc[0], 2)) {
> +               for (i = 0; i < 2; i++)
> +                       pca9532_pdata->psc[i] = psc[i];
> +       }
> +
> +       pca9532_pdata->gpio_base = -1; /* dynamically assign gpio base */
> +
> +       return pca9532_pdata;
> +}
> +
>  static int pca9532_probe(struct i2c_client *client,
>         const struct i2c_device_id *id)
>  {
> @@ -449,6 +487,9 @@ static int pca9532_probe(struct i2c_clie
>         struct pca9532_platform_data *pca9532_pdata =
>                         dev_get_platdata(&client->dev);
>
> +       if (IS_ENABLED(CONFIG_OF) && !pca9532_pdata && client->dev.of_node)
> +               pca9532_pdata = pca9532_parse_dt(&client->dev);
> +
>         if (!pca9532_pdata)
>                 return -EIO;
>