pinctrl: at91: add option to use drive strength bits

SAM9X60 uses high and low drive strengths. To implement this, in
at91_pinctrl_mux_ops::set_drivestrength and
at91_pinctrl_mux_ops::get_drivestrength we need bit numbers of
drive strengths (1 for low, 2 for high), thus change the code to
allow the usage of drive strength bit numbers.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/pinctrl-at91.c

@@ -72,10 +72,15 @@ static int gpio_banks;
  * DRIVE_STRENGTH_DEFAULT is just a placeholder to avoid changing the drive
  * strength when there is no dt config for it.
  */
-#define DRIVE_STRENGTH_DEFAULT		(0 << DRIVE_STRENGTH_SHIFT)
-#define DRIVE_STRENGTH_LOW          (1 << DRIVE_STRENGTH_SHIFT)
-#define DRIVE_STRENGTH_MED          (2 << DRIVE_STRENGTH_SHIFT)
-#define DRIVE_STRENGTH_HI           (3 << DRIVE_STRENGTH_SHIFT)
+enum drive_strength_bit {
+	DRIVE_STRENGTH_BIT_DEF,
+	DRIVE_STRENGTH_BIT_LOW,
+	DRIVE_STRENGTH_BIT_MED,
+	DRIVE_STRENGTH_BIT_HI,
+};
+
+#define DRIVE_STRENGTH_BIT_MSK(name)	(DRIVE_STRENGTH_BIT_##name << \
+					 DRIVE_STRENGTH_SHIFT)
 
 /**
  * struct at91_pmx_func - describes AT91 pinmux functions
@@ -551,7 +556,7 @@ static unsigned at91_mux_sama5d3_get_drivestrength(void __iomem *pio,
 	/* SAMA5 strength is 1:1 with our defines,
 	 * except 0 is equivalent to low per datasheet */
 	if (!tmp)
-		tmp = DRIVE_STRENGTH_LOW;
+		tmp = DRIVE_STRENGTH_BIT_MSK(LOW);
 
 	return tmp;
 }
@@ -564,7 +569,7 @@ static unsigned at91_mux_sam9x5_get_drivestrength(void __iomem *pio,
 
 	/* strength is inverse in SAM9x5s hardware with the pinctrl defines
 	 * hardware: 0 = hi, 1 = med, 2 = low, 3 = rsvd */
-	tmp = DRIVE_STRENGTH_HI - tmp;
+	tmp = DRIVE_STRENGTH_BIT_MSK(HI) - tmp;
 
 	return tmp;
 }
@@ -600,7 +605,7 @@ static void at91_mux_sam9x5_set_drivestrength(void __iomem *pio, unsigned pin,
 
 	/* strength is inverse on SAM9x5s with our defines
 	 * 0 = hi, 1 = med, 2 = low, 3 = rsvd */
-	setting = DRIVE_STRENGTH_HI - setting;
+	setting = DRIVE_STRENGTH_BIT_MSK(HI) - setting;
 
 	set_drive_strength(pio + at91sam9x5_get_drive_register(pin), pin,
 				setting);
@@ -959,11 +964,11 @@ static int at91_pinconf_set(struct pinctrl_dev *pctldev,
 	}					\
 } while (0)
 
-#define DBG_SHOW_FLAG_MASKED(mask,flag) do {	\
+#define DBG_SHOW_FLAG_MASKED(mask, flag, name) do { \
 	if ((config & mask) == flag) {		\
 		if (num_conf)			\
 			seq_puts(s, "|");	\
-		seq_puts(s, #flag);		\
+		seq_puts(s, #name);		\
 		num_conf++;			\
 	}					\
 } while (0)
@@ -981,9 +986,12 @@ static void at91_pinconf_dbg_show(struct pinctrl_dev *pctldev,
 	DBG_SHOW_FLAG(PULL_DOWN);
 	DBG_SHOW_FLAG(DIS_SCHMIT);
 	DBG_SHOW_FLAG(DEGLITCH);
-	DBG_SHOW_FLAG_MASKED(DRIVE_STRENGTH, DRIVE_STRENGTH_LOW);
-	DBG_SHOW_FLAG_MASKED(DRIVE_STRENGTH, DRIVE_STRENGTH_MED);
-	DBG_SHOW_FLAG_MASKED(DRIVE_STRENGTH, DRIVE_STRENGTH_HI);
+	DBG_SHOW_FLAG_MASKED(DRIVE_STRENGTH, DRIVE_STRENGTH_BIT_MSK(LOW),
+			     DRIVE_STRENGTH_LOW);
+	DBG_SHOW_FLAG_MASKED(DRIVE_STRENGTH, DRIVE_STRENGTH_BIT_MSK(MED),
+			     DRIVE_STRENGTH_MED);
+	DBG_SHOW_FLAG_MASKED(DRIVE_STRENGTH, DRIVE_STRENGTH_BIT_MSK(HI),
+			     DRIVE_STRENGTH_HI);
 	DBG_SHOW_FLAG(DEBOUNCE);
 	if (config & DEBOUNCE) {
 		val = config >> DEBOUNCE_VAL_SHIFT;