gpio: tps65910: Add sleep control support

The device tps65910/tps65911 supports the sleep
functionality in some of gpios. If gpio is configured
in output mode and sleep is enabled then during device
sleep state, the output of gpio becomes LOW regardless
of non-sleep output value.
Such gpio can be used to control regulator switch such
that output of regulator is off in device sleep state.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-tps65910.c

@@ -69,6 +69,7 @@ static int tps65910_gpio_input(struct gpio_chip *gc, unsigned offset)
 void tps65910_gpio_init(struct tps65910 *tps65910, int gpio_base)
 {
 	int ret;
+	struct tps65910_board *board_data;
 
 	if (!gpio_base)
 		return;
@@ -80,10 +81,10 @@ void tps65910_gpio_init(struct tps65910 *tps65910, int gpio_base)
 
 	switch(tps65910_chip_id(tps65910)) {
 	case TPS65910:
-		tps65910->gpio.ngpio	= 6;
+		tps65910->gpio.ngpio	= TPS65910_NUM_GPIO;
 		break;
 	case TPS65911:
-		tps65910->gpio.ngpio	= 9;
+		tps65910->gpio.ngpio	= TPS65911_NUM_GPIO;
 		break;
 	default:
 		return;
@@ -95,6 +96,21 @@ void tps65910_gpio_init(struct tps65910 *tps65910, int gpio_base)
 	tps65910->gpio.set		= tps65910_gpio_set;
 	tps65910->gpio.get		= tps65910_gpio_get;
 
+	/* Configure sleep control for gpios */
+	board_data = dev_get_platdata(tps65910->dev);
+	if (board_data) {
+		int i;
+		for (i = 0; i < tps65910->gpio.ngpio; ++i) {
+			if (board_data->en_gpio_sleep[i]) {
+				ret = tps65910_set_bits(tps65910,
+					TPS65910_GPIO0 + i, GPIO_SLEEP_MASK);
+				if (ret < 0)
+					dev_warn(tps65910->dev,
+						"GPIO Sleep setting failed\n");
+			}
+		}
+	}
+
 	ret = gpiochip_add(&tps65910->gpio);
 
 	if (ret)

include/linux/mfd/tps65910.h

@@ -657,6 +657,8 @@
 
 
 /*Register GPIO  (0x80) register.RegisterDescription */
+#define GPIO_SLEEP_MASK                         0x80
+#define GPIO_SLEEP_SHIFT                        7
 #define GPIO_DEB_MASK                           0x10
 #define GPIO_DEB_SHIFT                          4
 #define GPIO_PUEN_MASK                          0x08
@@ -740,6 +742,11 @@
 #define TPS65910_GPIO_STS				BIT(1)
 #define TPS65910_GPIO_SET				BIT(0)
 
+/* Max number of TPS65910/11 GPIOs */
+#define TPS65910_NUM_GPIO				6
+#define TPS65911_NUM_GPIO				9
+#define TPS6591X_MAX_NUM_GPIO				9
+
 /* Regulator Index Definitions */
 #define TPS65910_REG_VRTC				0
 #define TPS65910_REG_VIO				1
@@ -779,6 +786,7 @@ struct tps65910_board {
 	int irq_base;
 	int vmbch_threshold;
 	int vmbch2_threshold;
+	bool en_gpio_sleep[TPS6591X_MAX_NUM_GPIO];
 	struct regulator_init_data *tps65910_pmic_init_data[TPS65910_NUM_REGS];
 };