3 files changed, 40 insertions, 1 deletions

diff --git a/drivers/media/usb/em28xx/em28xx-core.c b/drivers/media/usb/em28xx/em28xx-core.c
index 4a8179aafc4d..fc8254035278 100644
--- a/drivers/media/usb/em28xx/em28xx-core.c
+++ b/drivers/media/usb/em28xx/em28xx-core.c
@@ -226,6 +226,25 @@ int em28xx_write_reg_bits(struct em28xx *dev, u16 reg, u8 val,
 EXPORT_SYMBOL_GPL(em28xx_write_reg_bits);
 
 /*
+ * em28xx_toggle_reg_bits()
+ * toggles/inverts the bits (specified by bitmask) of a register
+ */
+int em28xx_toggle_reg_bits(struct em28xx *dev, u16 reg, u8 bitmask)
+{
+	int oldval;
+	u8 newval;
+
+	oldval = em28xx_read_reg(dev, reg);
+	if (oldval < 0)
+		return oldval;
+
+	newval = (~oldval & bitmask) | (oldval & ~bitmask);
+
+	return em28xx_write_reg(dev, reg, newval);
+}
+EXPORT_SYMBOL_GPL(em28xx_toggle_reg_bits);
+
+/*
  * em28xx_is_ac97_ready()
  * Checks if ac97 is ready
  */
diff --git a/drivers/media/usb/em28xx/em28xx-input.c b/drivers/media/usb/em28xx/em28xx-input.c
index ebc538730e07..e0acc92f0dfd 100644
--- a/drivers/media/usb/em28xx/em28xx-input.c
+++ b/drivers/media/usb/em28xx/em28xx-input.c
@@ -480,6 +480,7 @@ static void em28xx_query_buttons(struct work_struct *work)
 	u8 i, j;
 	int regval;
 	bool is_pressed, was_pressed;
+	const struct em28xx_led *led;
 
 	/* Poll and evaluate all addresses */
 	for (i = 0; i < dev->num_button_polling_addresses; i++) {
@@ -524,6 +525,15 @@ static void em28xx_query_buttons(struct work_struct *work)
 				input_report_key(dev->sbutton_input_dev,
 						 EM28XX_SNAPSHOT_KEY, 0);
 				break;
+			case EM28XX_BUTTON_ILLUMINATION:
+				led = em28xx_find_led(dev,
+						      EM28XX_LED_ILLUMINATION);
+				/* Switch illumination LED on/off */
+				if (led)
+					em28xx_toggle_reg_bits(dev,
+							       led->gpio_reg,
+							       led->gpio_mask);
+				break;
 			default:
 				WARN_ONCE(1, "BUG: unhandled button role.");
 			}
@@ -600,10 +610,17 @@ static void em28xx_init_buttons(struct em28xx *dev)
 			WARN_ONCE(1, "BUG: maximum number of button polling addresses exceeded.");
 			addr_new = 0;
 		}
-		/* Register input device (if needed) */
+		/* Button role specific checks and actions */
 		if (button->role == EM28XX_BUTTON_SNAPSHOT) {
+			/* Register input device */
 			if (em28xx_register_snapshot_button(dev) < 0)
 				addr_new = 0;
+		} else if (button->role == EM28XX_BUTTON_ILLUMINATION) {
+			/* Check sanity */
+			if (!em28xx_find_led(dev, EM28XX_LED_ILLUMINATION)) {
+				em28xx_errdev("BUG: illumination button defined, but no illumination LED.\n");
+				addr_new = 0;
+			}
 		}
 		/* Add read address to list of polling addresses */
 		if (addr_new) {
diff --git a/drivers/media/usb/em28xx/em28xx.h b/drivers/media/usb/em28xx/em28xx.h
index f60f236a245f..43e29683eb6a 100644
--- a/drivers/media/usb/em28xx/em28xx.h
+++ b/drivers/media/usb/em28xx/em28xx.h
@@ -379,6 +379,7 @@ enum em28xx_adecoder {
 
 enum em28xx_led_role {
 	EM28XX_LED_ANALOG_CAPTURING = 0,
+	EM28XX_LED_ILLUMINATION,
 	EM28XX_NUM_LED_ROLES, /* must be the last */
 };
 
@@ -391,6 +392,7 @@ struct em28xx_led {
 
 enum em28xx_button_role {
 	EM28XX_BUTTON_SNAPSHOT = 0,
+	EM28XX_BUTTON_ILLUMINATION,
 	EM28XX_NUM_BUTTON_ROLES, /* must be the last */
 };
 
@@ -709,6 +711,7 @@ int em28xx_write_regs(struct em28xx *dev, u16 reg, char *buf, int len);
 int em28xx_write_reg(struct em28xx *dev, u16 reg, u8 val);
 int em28xx_write_reg_bits(struct em28xx *dev, u16 reg, u8 val,
 				 u8 bitmask);
+int em28xx_toggle_reg_bits(struct em28xx *dev, u16 reg, u8 bitmask);
 
 int em28xx_read_ac97(struct em28xx *dev, u8 reg);
 int em28xx_write_ac97(struct em28xx *dev, u8 reg, u16 val);