mfd: wm5102: Mark register write sequencer control 3 readable

During init the core checks if the wm5102 has finished starting by reading
register 0x19 and looking at the value. This read always fails since this
is not a readable register, mark it as being one. While we're at it provide
a constant for the register name (as supplied by Charles Keepax).
Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/mfd/arizona-core.c

@@ -784,7 +784,8 @@ int arizona_dev_init(struct arizona *arizona)
 	/* Ensure device startup is complete */
 	switch (arizona->type) {
 	case WM5102:
-		ret = regmap_read(arizona->regmap, 0x19, &val);
+		ret = regmap_read(arizona->regmap,
+				  ARIZONA_WRITE_SEQUENCER_CTRL_3, &val);
 		if (ret != 0)
 			dev_err(dev,
 				"Failed to check write sequencer state: %d\n",

drivers/mfd/wm5102-tables.c

@@ -1017,6 +1017,7 @@ static bool wm5102_readable_register(struct device *dev, unsigned int reg)
 	case ARIZONA_WRITE_SEQUENCER_CTRL_0:
 	case ARIZONA_WRITE_SEQUENCER_CTRL_1:
 	case ARIZONA_WRITE_SEQUENCER_CTRL_2:
+	case ARIZONA_WRITE_SEQUENCER_CTRL_3:
 	case ARIZONA_WRITE_SEQUENCER_PROM:
 	case ARIZONA_TONE_GENERATOR_1:
 	case ARIZONA_TONE_GENERATOR_2:

include/linux/mfd/arizona/registers.h

@@ -27,6 +27,7 @@
 #define ARIZONA_WRITE_SEQUENCER_CTRL_0           0x16
 #define ARIZONA_WRITE_SEQUENCER_CTRL_1           0x17
 #define ARIZONA_WRITE_SEQUENCER_CTRL_2           0x18
+#define ARIZONA_WRITE_SEQUENCER_CTRL_3           0x19
 #define ARIZONA_WRITE_SEQUENCER_PROM             0x1A
 #define ARIZONA_TONE_GENERATOR_1                 0x20
 #define ARIZONA_TONE_GENERATOR_2                 0x21