pinctrl: at91: add support for OUTPUT config

Add support for pin output control through the pinctrl config:
- support enabling/disabling output on a given pin
- support output level setting (high or low)

Signed-off-by: Boris BREZILLON <[e-mail]>
Acked-by: Nicolas Ferre <[e-mail]>
Signed-off-by: Wenyou Yang <[e-mail]>
Signed-off-by: Linus Walleij <[e-mail]>

Documentation/devicetree/bindings/pinctrl/atmel,at91-pinctrl.txt

···
 				01 - Low
 				10 - Medium
 				11 - High
+OUTPUT		(1 << 7): indicate this pin need to be configured as an output.
+OUTPUT_VAL	(1 << 8): output val (1 = high, 0 = low)
 DEBOUNCE	(1 << 16): indicate this pin needs debounce.
 DEBOUNCE_VAL	(0x3fff << 17): debounce value.
 

drivers/pinctrl/pinctrl-at91.c

···
 #define DRIVE_STRENGTH_SHIFT	5
 #define DRIVE_STRENGTH_MASK		0x3
 #define DRIVE_STRENGTH   (DRIVE_STRENGTH_MASK << DRIVE_STRENGTH_SHIFT)
+#define OUTPUT		(1 << 7)
+#define OUTPUT_VAL_SHIFT	8
+#define OUTPUT_VAL	(0x1 << OUTPUT_VAL_SHIFT)
 #define DEBOUNCE	(1 << 16)
 #define DEBOUNCE_VAL_SHIFT	17
 #define DEBOUNCE_VAL	(0x3fff << DEBOUNCE_VAL_SHIFT)
···
 		writel_relaxed(mask, pio + PIO_PPDDR);
 
 	writel_relaxed(mask, pio + (on ? PIO_PUER : PIO_PUDR));
+}
+
+static bool at91_mux_get_output(void __iomem *pio, unsigned int pin, bool *val)
+{
+	*val = (readl_relaxed(pio + PIO_ODSR) >> pin) & 0x1;
+	return (readl_relaxed(pio + PIO_OSR) >> pin) & 0x1;
+}
+
+static void at91_mux_set_output(void __iomem *pio, unsigned int mask,
+				bool is_on, bool val)
+{
+	writel_relaxed(mask, pio + (val ? PIO_SODR : PIO_CODR));
+	writel_relaxed(mask, pio + (is_on ? PIO_OER : PIO_ODR));
 }
 
 static unsigned at91_mux_get_multidrive(void __iomem *pio, unsigned pin)
···
 	void __iomem *pio;
 	unsigned pin;
 	int div;
+	bool out;
 
 	*config = 0;
 	dev_dbg(info->dev, "%s:%d, pin_id=%d", __func__, __LINE__, pin_id);
···
 	if (info->ops->get_drivestrength)
 		*config |= (info->ops->get_drivestrength(pio, pin)
 				<< DRIVE_STRENGTH_SHIFT);
+	if (at91_mux_get_output(pio, pin, &out))
+		*config |= OUTPUT | (out << OUTPUT_VAL_SHIFT);
 
 	return 0;
 }
···
 		if (config & PULL_UP && config & PULL_DOWN)
 			return -EINVAL;
 
+		at91_mux_set_output(pio, mask, config & OUTPUT,
+				    (config & OUTPUT_VAL) >> OUTPUT_VAL_SHIFT);
 		at91_mux_set_pullup(pio, mask, config & PULL_UP);
 		at91_mux_set_multidrive(pio, mask, config & MULTI_DRIVE);
 		if (info->ops->set_deglitch)

include/dt-bindings/pinctrl/at91.h

···
 #define AT91_PINCTRL_DEGLITCH		(1 << 2)
 #define AT91_PINCTRL_PULL_DOWN		(1 << 3)
 #define AT91_PINCTRL_DIS_SCHMIT		(1 << 4)
+#define AT91_PINCTRL_OUTPUT		(1 << 7)
+#define AT91_PINCTRL_OUTPUT_VAL(x)	((x & 0x1) << 8)
 #define AT91_PINCTRL_DEBOUNCE		(1 << 16)
 #define AT91_PINCTRL_DEBOUNCE_VAL(x)	(x << 17)