mfd: Conditionally add WM831x backlight subdevice

The WM831x backlight driver requires at least the specification of the
current sink to use and a maximum current to allow them to function and
will actively interfere with other users of the regulators it uses if
misconfigured so only register the subdevice for it if this platform
data has been supplied.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

diff --git a/drivers/mfd/wm831x-core.c b/drivers/mfd/wm831x-core.c
index 42bef1dd2ca1028d5d9fb45a8827340086b491d2..bc40ea315cc0570487326ac24208bdaea99b4bc1 100644 (file)
--- a/drivers/mfd/wm831x-core.c
+++ b/drivers/mfd/wm831x-core.c
@@ -1172,6 +1172,12 @@ static struct mfd_cell wm8312_devs[] = {
        },
 };
 
+static struct mfd_cell backlight_devs[] = {
+       {
+               .name = "wm831x-backlight",
+       },
+};
+
 /*
  * Instantiate the generic non-control parts of the device.
  */
@@ -1325,6 +1331,15 @@ static int wm831x_device_init(struct wm831x *wm831x, unsigned long id, int irq)
                goto err_irq;
        }
 
+       if (pdata && pdata->backlight) {
+               /* Treat errors as non-critical */
+               ret = mfd_add_devices(wm831x->dev, -1, backlight_devs,
+                                     ARRAY_SIZE(backlight_devs), NULL, 0);
+               if (ret < 0)
+                       dev_err(wm831x->dev, "Failed to add backlight: %d\n",
+                               ret);
+       }
+
        if (pdata && pdata->post_init) {
                ret = pdata->post_init(wm831x);
                if (ret != 0) {

diff --git a/include/linux/mfd/wm831x/pdata.h b/include/linux/mfd/wm831x/pdata.h
index 571e6013626432b75d93da8644a45e342f02a6a8..90d820260aad579638fdfacd6d7e04a2ac12c907 100644 (file)
--- a/include/linux/mfd/wm831x/pdata.h
+++ b/include/linux/mfd/wm831x/pdata.h
@@ -18,6 +18,11 @@
 struct wm831x;
 struct regulator_init_data;
 
+struct wm831x_backlight_pdata {
+       int isink;     /** ISINK to use, 1 or 2 */
+       int max_uA;    /** Maximum current to allow */
+};
+
 struct wm831x_backup_pdata {
        int charger_enable;
        int no_constant_voltage;  /** Disable constant voltage charging */
@@ -87,6 +92,7 @@ struct wm831x_pdata {
        int (*post_init)(struct wm831x *wm831x);
 
        int gpio_base;
+       struct wm831x_backlight_pdata *backlight;
        struct wm831x_backup_pdata *backup;
        struct wm831x_battery_pdata *battery;
        struct wm831x_touch_pdata *touch;