From 035e3ba750e10e8bb63b59e3fd138dcbe584b33e Mon Sep 17 00:00:00 2001
From: =?utf8?q?=E5=BC=A0=E6=99=B4?= <zhangqing@rock-chips.com>
Date: Thu, 3 May 2012 13:50:32 +0800
Subject: [PATCH] rk30:sdk:Support wm8326 adc for low battery detection

---
 arch/arm/mach-rk30/board-rk30-sdk-wm8326.c | 26 +++++++++++++++++++
 drivers/mfd/wm831x-core.c                  | 29 ++++++++++++++++++++++
 drivers/power/Kconfig                      |  4 +++
 3 files changed, 59 insertions(+)

diff --git a/arch/arm/mach-rk30/board-rk30-sdk-wm8326.c b/arch/arm/mach-rk30/board-rk30-sdk-wm8326.c
index b7babb99f2a6..92e2480af09c 100755
--- a/arch/arm/mach-rk30/board-rk30-sdk-wm8326.c
+++ b/arch/arm/mach-rk30/board-rk30-sdk-wm8326.c
@@ -140,6 +140,27 @@ static int wm831x_mask_interrupt(struct wm831x *Wm831x)
 	/*****************************************************************/
 }
 
+#ifdef CONFIG_WM8326_VBAT_LOW_DETECTION
+static int wm831x_low_power_detection(struct wm831x *wm831x)
+{
+	wm831x_reg_write(wm831x,WM831X_AUXADC_CONTROL,0x803f);     //open adc 
+	wm831x_reg_write(wm831x,WM831X_AUXADC_CONTROL,0xd03f);
+	wm831x_reg_write(wm831x,WM831X_AUXADC_SOURCE,0x0001);
+	
+	wm831x_reg_write(wm831x,WM831X_COMPARATOR_CONTROL,0x0001);
+	wm831x_reg_write(wm831x,WM831X_COMPARATOR_1,0x2910);   //set the low power is 3.4v
+	
+	wm831x_reg_write(wm831x,WM831X_INTERRUPT_STATUS_1_MASK,0x99ee);
+	wm831x_set_bits(wm831x,WM831X_SYSTEM_INTERRUPTS_MASK,0x0100,0x0000);
+	if (wm831x_reg_read(wm831x,WM831X_AUXADC_DATA)< 0x1900){
+		printk("The vbat is too low.\n");
+		wm831x_device_shutdown(wm831x);
+	}
+	return 0;
+}
+#endif
+
+
 int wm831x_post_init(struct wm831x *Wm831x)
 {
 	struct regulator *dcdc;
@@ -258,6 +279,11 @@ int wm831x_post_init(struct wm831x *Wm831x)
 	udelay(100);
 
 	wm831x_mask_interrupt(Wm831x);
+
+	#ifdef CONFIG_WM8326_VBAT_LOW_DETECTION
+	wm831x_low_power_detection(Wm831x);
+	#endif
+	
 	printk("wm831x_post_init end");
 	return 0;
 }
diff --git a/drivers/mfd/wm831x-core.c b/drivers/mfd/wm831x-core.c
index bb5016ad104e..4fc2b755a6e2 100755
--- a/drivers/mfd/wm831x-core.c
+++ b/drivers/mfd/wm831x-core.c
@@ -28,6 +28,8 @@
 #include <linux/mfd/wm831x/regulator.h>
 #include <linux/mfd/wm831x/pmu.h>
 
+#include <mach/board.h>
+
 
 /* Current settings - values are 2*2^(reg_val/4) microamps.  These are
  * exported since they are used by multiple drivers.
@@ -421,6 +423,15 @@ out:
 }
 EXPORT_SYMBOL_GPL(wm831x_auxadc_read);
 
+#ifdef CONFIG_WM8326_VBAT_LOW_DETECTION
+static irqreturn_t wm831x_vbatlo_irq(int irq, void *irq_data)
+{
+	rk28_send_wakeup_key();
+
+	return IRQ_HANDLED;
+}
+#endif
+
 static irqreturn_t wm831x_auxadc_irq(int irq, void *irq_data)
 {
 	struct wm831x *wm831x = irq_data;
@@ -1617,14 +1628,32 @@ int wm831x_device_init(struct wm831x *wm831x, unsigned long id, int irq)
 	if (ret != 0)
 		goto err;
 
+	switch (parent) {
+	#ifdef CONFIG_WM8326_VBAT_LOW_DETECTION
+	case WM8326:
+		if (wm831x->irq_base) {
+		ret = request_threaded_irq(wm831x->irq_base +
+					   WM831X_IRQ_AUXADC_DCOMP1,
+					   NULL, wm831x_vbatlo_irq, IRQF_TRIGGER_RISING,
+					   "dcomp1", wm831x);
+			}
+		if (ret < 0)
+			dev_err(wm831x->dev, "dcomp1 IRQ request failed: %d\n",
+				ret);
+		break;
+	#endif
+
+	default:	
 	if (wm831x->irq_base) {
 		ret = request_threaded_irq(wm831x->irq_base +
 					   WM831X_IRQ_AUXADC_DATA,
 					   NULL, wm831x_auxadc_irq, 0,
 					   "auxadc", wm831x);
+		}
 		if (ret < 0)
 			dev_err(wm831x->dev, "AUXADC IRQ request failed: %d\n",
 				ret);
+	
 	}
 
 	/* The core device is up, instantiate the subdevices. */
diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
index a543004b34e1..caacf8bd6473 100755
--- a/drivers/power/Kconfig
+++ b/drivers/power/Kconfig
@@ -325,4 +325,8 @@ config BATTERY_RK30_VOL3V8
 config POWER_ON_CHARGER_DISPLAY
 	bool "Support charger display"
 
+config WM8326_VBAT_LOW_DETECTION
+	tristate "Support for WM8326 battery voltage detection."
+	default n
+
 endif # POWER_SUPPLY
-- 
2.34.1