leds: Add WM8350 LED driver

The voltage and current regulators on the WM8350 AudioPlus PMIC can be
used in concert to provide a power efficient LED driver.  This driver
implements support for this within the standard LED class.

Platform initialisation code should configure the LED hardware in the
init callback provided by the WM8350 core driver.  The callback should
use wm8350_isink_set_flash(), wm8350_dcdc25_set_mode() and
wm8350_dcdc_set_slot() to configure the operating parameters of the
regulators for their hardware and then then use wm8350_register_led() to
instantiate the LED driver.

This driver was originally written by Liam Girdwood, though it has been
extensively modified since then.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>

1 files changed, 91 insertions, 0 deletions

diff --git a/drivers/regulator/wm8350-regulator.c b/drivers/regulator/wm8350-regulator.c
index c68c496b2c49..7aa35248181b 100644
--- a/drivers/regulator/wm8350-regulator.c
+++ b/drivers/regulator/wm8350-regulator.c
@@ -1412,6 +1412,97 @@ int wm8350_register_regulator(struct wm8350 *wm8350, int reg,
 }
 EXPORT_SYMBOL_GPL(wm8350_register_regulator);
 
+/**
+ * wm8350_register_led - Register a WM8350 LED output
+ *
+ * @param wm8350 The WM8350 device to configure.
+ * @param lednum LED device index to create.
+ * @param dcdc The DCDC to use for the LED.
+ * @param isink The ISINK to use for the LED.
+ * @param pdata Configuration for the LED.
+ *
+ * The WM8350 supports the use of an ISINK together with a DCDC to
+ * provide a power-efficient LED driver.  This function registers the
+ * regulators and instantiates the platform device for a LED.  The
+ * operating modes for the LED regulators must be configured using
+ * wm8350_isink_set_flash(), wm8350_dcdc25_set_mode() and
+ * wm8350_dcdc_set_slot() prior to calling this function.
+ */
+int wm8350_register_led(struct wm8350 *wm8350, int lednum, int dcdc, int isink,
+                        struct wm8350_led_platform_data *pdata)
+{
+        struct wm8350_led *led;
+        struct platform_device *pdev;
+        int ret;
+
+        if (lednum > ARRAY_SIZE(wm8350->pmic.led) || lednum < 0) {
+                dev_err(wm8350->dev, "Invalid LED index %d\n", lednum);
+                return -ENODEV;
+        }
+
+        led = &wm8350->pmic.led[lednum];
+
+        if (led->pdev) {
+                dev_err(wm8350->dev, "LED %d already allocated\n", lednum);
+                return -EINVAL;
+        }
+
+        pdev = platform_device_alloc("wm8350-led", lednum);
+        if (pdev == NULL) {
+                dev_err(wm8350->dev, "Failed to allocate LED %d\n", lednum);
+                return -ENOMEM;
+        }
+
+        led->isink_consumer.dev = &pdev->dev;
+        led->isink_consumer.supply = "led_isink";
+        led->isink_init.num_consumer_supplies = 1;
+        led->isink_init.consumer_supplies = &led->isink_consumer;
+        led->isink_init.constraints.min_uA = 0;
+        led->isink_init.constraints.max_uA = pdata->max_uA;
+        led->isink_init.constraints.valid_ops_mask = REGULATOR_CHANGE_CURRENT;
+        led->isink_init.constraints.valid_modes_mask = REGULATOR_MODE_NORMAL;
+        ret = wm8350_register_regulator(wm8350, isink, &led->isink_init);
+        if (ret != 0) {
+                platform_device_put(pdev);
+                return ret;
+        }
+
+        led->dcdc_consumer.dev = &pdev->dev;
+        led->dcdc_consumer.supply = "led_vcc";
+        led->dcdc_init.num_consumer_supplies = 1;
+        led->dcdc_init.consumer_supplies = &led->dcdc_consumer;
+        led->dcdc_init.constraints.valid_modes_mask = REGULATOR_MODE_NORMAL;
+        ret = wm8350_register_regulator(wm8350, dcdc, &led->dcdc_init);
+        if (ret != 0) {
+                platform_device_put(pdev);
+                return ret;
+        }
+
+        switch (isink) {
+        case WM8350_ISINK_A:
+                wm8350->pmic.isink_A_dcdc = dcdc;
+                break;
+        case WM8350_ISINK_B:
+                wm8350->pmic.isink_B_dcdc = dcdc;
+                break;
+        }
+
+        pdev->dev.platform_data = pdata;
+        pdev->dev.parent = wm8350->dev;
+        ret = platform_device_add(pdev);
+        if (ret != 0) {
+                dev_err(wm8350->dev, "Failed to register LED %d: %d\n",
+                        lednum, ret);
+                platform_device_put(pdev);
+                return ret;
+        }
+
+        led->pdev = pdev;
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(wm8350_register_led);
+
 static struct platform_driver wm8350_regulator_driver = {
         .probe = wm8350_regulator_probe,
         .remove = wm8350_regulator_remove,