mfd: Only register wm831x RTC device if the 32.768kHz crystal is enabled

[pandora-kernel.git] / drivers / mfd / wm831x-core.c

diff --git a/drivers/mfd/wm831x-core.c b/drivers/mfd/wm831x-core.c
index ff57a16..58f033b 100644 (file)
--- a/drivers/mfd/wm831x-core.c
+++ b/drivers/mfd/wm831x-core.c
@@ -975,11 +975,6 @@ static struct mfd_cell wm8310_devs[] = {
                .num_resources = ARRAY_SIZE(wm831x_power_resources),
                .resources = wm831x_power_resources,
        },
-       {
-               .name = "wm831x-rtc",
-               .num_resources = ARRAY_SIZE(wm831x_rtc_resources),
-               .resources = wm831x_rtc_resources,
-       },
        {
                .name = "wm831x-status",
                .id = 1,
@@ -1107,11 +1102,6 @@ static struct mfd_cell wm8311_devs[] = {
                .num_resources = ARRAY_SIZE(wm831x_power_resources),
                .resources = wm831x_power_resources,
        },
-       {
-               .name = "wm831x-rtc",
-               .num_resources = ARRAY_SIZE(wm831x_rtc_resources),
-               .resources = wm831x_rtc_resources,
-       },
        {
                .name = "wm831x-status",
                .id = 1,
@@ -1263,11 +1253,6 @@ static struct mfd_cell wm8312_devs[] = {
                .num_resources = ARRAY_SIZE(wm831x_power_resources),
                .resources = wm831x_power_resources,
        },
-       {
-               .name = "wm831x-rtc",
-               .num_resources = ARRAY_SIZE(wm831x_rtc_resources),
-               .resources = wm831x_rtc_resources,
-       },
        {
                .name = "wm831x-status",
                .id = 1,
@@ -1394,11 +1379,6 @@ static struct mfd_cell wm8320_devs[] = {
                .num_resources = ARRAY_SIZE(wm831x_on_resources),
                .resources = wm831x_on_resources,
        },
-       {
-               .name = "wm831x-rtc",
-               .num_resources = ARRAY_SIZE(wm831x_rtc_resources),
-               .resources = wm831x_rtc_resources,
-       },
        {
                .name = "wm831x-status",
                .id = 1,
@@ -1426,6 +1406,13 @@ static struct mfd_cell touch_devs[] = {
        },
 };
 
+static struct mfd_cell rtc_devs[] = {
+       {
+               .name = "wm831x-rtc",
+               .num_resources = ARRAY_SIZE(wm831x_rtc_resources),
+               .resources = wm831x_rtc_resources,
+       },
+};
 
 static struct mfd_cell backlight_devs[] = {
        {
@@ -1658,6 +1645,27 @@ int wm831x_device_init(struct wm831x *wm831x, unsigned long id, int irq)
                goto err_irq;
        }
 
+       /* The RTC can only be used if the 32.768kHz crystal is
+        * enabled; this can't be controlled by software at runtime.
+        */
+       ret = wm831x_reg_read(wm831x, WM831X_CLOCK_CONTROL_2);
+       if (ret < 0) {
+               dev_err(wm831x->dev, "Failed to read clock status: %d\n", ret);
+               goto err_irq;
+       }
+
+       if (ret & WM831X_XTAL_ENA) {
+               ret = mfd_add_devices(wm831x->dev, wm831x_num,
+                                     rtc_devs, ARRAY_SIZE(rtc_devs),
+                                     NULL, wm831x->irq_base);
+               if (ret != 0) {
+                       dev_err(wm831x->dev, "Failed to add RTC: %d\n", ret);
+                       goto err_irq;
+               }
+       } else {
+               dev_info(wm831x->dev, "32.768kHz clock disabled, no RTC\n");
+       }
+
        if (pdata && pdata->backlight) {
                /* Treat errors as non-critical */
                ret = mfd_add_devices(wm831x->dev, wm831x_num, backlight_devs,