regulator: rpi-panel: Ensure the backlight is off during probe.

The initial state of the Atmel is not defined, so ensure the
backlight PWM is set to 0 by default.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com>
Link: https://lore.kernel.org/r/20220124220129.158891-5-detlev.casanova@collabora.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/regulator/rpi-panel-attiny-regulator.c b/drivers/regulator/rpi-panel-attiny-regulator.c
index a4af7adad2b5e08c709e8ecdc3029715230a303b..b3629a1e0e502fbd7a32f8b310463681e3d55fb6 100644 (file)
--- a/drivers/regulator/rpi-panel-attiny-regulator.c
+++ b/drivers/regulator/rpi-panel-attiny-regulator.c
@@ -250,6 +250,7 @@ static int attiny_i2c_probe(struct i2c_client *i2c,
 
        regmap_write(regmap, REG_POWERON, 0);
        msleep(30);
+       regmap_write(regmap, REG_PWM, 0);
 
        config.dev = &i2c->dev;
        config.regmap = regmap;