atmel-mci: Add support for inverted detect pin

Same patch as before, modified to use bool. Also adds description of
the new field in struct atmel_mci that I missed in the first patch.

This patch adds Atmel MCI support for inverted detect pins.
Signed-off-by: NJonas Larsson <jonas.larsson@martinsson.se>
Acked-by: NPierre Ossman <pierre@ossman.eu>
Signed-off-by: NHaavard Skinnemoen <haavard.skinnemoen@atmel.com>

drivers/mmc/host/atmel-mci.c

@@ -177,6 +177,7 @@ struct atmel_mci {
  *	available.
  * @wp_pin: GPIO pin used for card write protect sending, or negative
  *	if not available.
+ * @detect_is_active_high: The state of the detect pin when it is active.
  * @detect_timer: Timer used for debouncing @detect_pin interrupts.
  */
 struct atmel_mci_slot {
@@ -196,6 +197,7 @@ struct atmel_mci_slot {
 
 	int			detect_pin;
 	int			wp_pin;
+	bool			detect_is_active_high;
 
 	struct timer_list	detect_timer;
 };
@@ -924,7 +926,8 @@ static int atmci_get_cd(struct mmc_host *mmc)
 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
 
 	if (gpio_is_valid(slot->detect_pin)) {
-		present = !gpio_get_value(slot->detect_pin);
+		present = !(gpio_get_value(slot->detect_pin) ^
+			    slot->detect_is_active_high);
 		dev_dbg(&mmc->class_dev, "card is %spresent\n",
 				present ? "" : "not ");
 	}
@@ -1028,7 +1031,8 @@ static void atmci_detect_change(unsigned long data)
 		return;
 
 	enable_irq(gpio_to_irq(slot->detect_pin));
-	present = !gpio_get_value(slot->detect_pin);
+	present = !(gpio_get_value(slot->detect_pin) ^
+		    slot->detect_is_active_high);
 	present_old = test_bit(ATMCI_CARD_PRESENT, &slot->flags);
 
 	dev_vdbg(&slot->mmc->class_dev, "detect change: %d (was %d)\n",
@@ -1456,6 +1460,7 @@ static int __init atmci_init_slot(struct atmel_mci *host,
 	slot->host = host;
 	slot->detect_pin = slot_data->detect_pin;
 	slot->wp_pin = slot_data->wp_pin;
+	slot->detect_is_active_high = slot_data->detect_is_active_high;
 	slot->sdc_reg = sdc_reg;
 
 	mmc->ops = &atmci_ops;
@@ -1477,7 +1482,8 @@ static int __init atmci_init_slot(struct atmel_mci *host,
 		if (gpio_request(slot->detect_pin, "mmc_detect")) {
 			dev_dbg(&mmc->class_dev, "no detect pin available\n");
 			slot->detect_pin = -EBUSY;
-		} else if (gpio_get_value(slot->detect_pin)) {
+		} else if (gpio_get_value(slot->detect_pin) ^
+				slot->detect_is_active_high) {
 			clear_bit(ATMCI_CARD_PRESENT, &slot->flags);
 		}
 	}

include/linux/atmel-mci.h

@@ -10,6 +10,7 @@
  * @bus_width: Number of data lines wired up the slot
  * @detect_pin: GPIO pin wired to the card detect switch
  * @wp_pin: GPIO pin wired to the write protect sensor
+ * @detect_is_active_high: The state of the detect pin when it is active
  *
  * If a given slot is not present on the board, @bus_width should be
  * set to 0. The other fields are ignored in this case.
@@ -24,6 +25,7 @@ struct mci_slot_pdata {
 	unsigned int		bus_width;
 	int			detect_pin;
 	int			wp_pin;
+	bool			detect_is_active_high;
 };
 
 /**