2 files changed, 42 insertions, 0 deletions

diff --git a/drivers/input/touchscreen/wm97xx-core.c b/drivers/input/touchscreen/wm97xx-core.c
index fec07c28281a..e9c7ea46b6e3 100644
--- a/drivers/input/touchscreen/wm97xx-core.c
+++ b/drivers/input/touchscreen/wm97xx-core.c
@@ -262,6 +262,23 @@ void wm97xx_config_gpio(struct wm97xx *wm, u32 gpio, enum wm97xx_gpio_dir dir,
 EXPORT_SYMBOL_GPL(wm97xx_config_gpio);
 
 /*
+ * Configure the WM97XX_PRP value to use while system is suspended.
+ * If a value other than 0 is set then WM97xx pen detection will be
+ * left enabled in the configured mode while the system is in suspend,
+ * the device has users and suspend has not been disabled via the
+ * wakeup sysfs entries.
+ *
+ * @wm:   WM97xx device to configure
+ * @mode: WM97XX_PRP value to configure while suspended
+ */
+void wm97xx_set_suspend_mode(struct wm97xx *wm, u16 mode)
+{
+        wm->suspend_mode = mode;
+        device_init_wakeup(&wm->input_dev->dev, mode != 0);
+}
+EXPORT_SYMBOL_GPL(wm97xx_set_suspend_mode);
+
+/*
  * Handle a pen down interrupt.
  */
 static void wm97xx_pen_irq_worker(struct work_struct *work)
@@ -689,10 +706,32 @@ static int wm97xx_remove(struct device *dev)
 static int wm97xx_suspend(struct device *dev, pm_message_t state)
 {
         struct wm97xx *wm = dev_get_drvdata(dev);
+        u16 reg;
+        int suspend_mode;
+
+        if (device_may_wakeup(&wm->input_dev->dev))
+                suspend_mode = wm->suspend_mode;
+        else
+                suspend_mode = 0;
 
         if (wm->input_dev->users)
                 cancel_delayed_work_sync(&wm->ts_reader);
 
+        /* Power down the digitiser (bypassing the cache for resume) */
+        reg = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER2);
+        reg &= ~WM97XX_PRP_DET_DIG;
+        if (wm->input_dev->users)
+                reg |= suspend_mode;
+        wm->ac97->bus->ops->write(wm->ac97, AC97_WM97XX_DIGITISER2, reg);
+
+        /* WM9713 has an additional power bit - turn it off if there
+         * are no users or if suspend mode is zero. */
+        if (wm->id == WM9713_ID2 &&
+            (!wm->input_dev->users || !suspend_mode)) {
+                reg = wm97xx_reg_read(wm, AC97_EXTENDED_MID) | 0x8000;
+                wm97xx_reg_write(wm, AC97_EXTENDED_MID, reg);
+        }
+
         return 0;
 }
 
diff --git a/include/linux/wm97xx.h b/include/linux/wm97xx.h
index ed01c7df54a3..4d13732e9cf0 100644
--- a/include/linux/wm97xx.h
+++ b/include/linux/wm97xx.h
@@ -282,6 +282,7 @@ struct wm97xx {
         unsigned pen_is_down:1;         /* Pen is down */
         unsigned aux_waiting:1;         /* aux measurement waiting */
         unsigned pen_probably_down:1;   /* used in polling mode */
+        u16 suspend_mode;               /* PRP in suspend mode */
 };
 
 /*
@@ -297,6 +298,8 @@ void wm97xx_config_gpio(struct wm97xx *wm, u32 gpio,
                                      enum wm97xx_gpio_sticky sticky,
                                      enum wm97xx_gpio_wake wake);
 
+void wm97xx_set_suspend_mode(struct wm97xx *wm, u16 mode);
+
 /* codec AC97 IO access */
 int wm97xx_reg_read(struct wm97xx *wm, u16 reg);
 void wm97xx_reg_write(struct wm97xx *wm, u16 reg, u16 val);