4.4-stable review patch. If anyone has any objections, please let me know.
------------------ From: Wolfram Sang <[email protected]> commit d0be8584b01160eb6f49e77f8e9c1da286bb4ffb upstream. The interrupts for EDID_READY or DDC_ERROR were never enabled in this driver, so reading EDID always timed out when chip was powered down and interrupts were used. Fix this and also remove clearing the interrupt flags, they are cleared in POWER_DOWN mode anyhow (unlike the interrupt enable flags) according to docs and my tests. Signed-off-by: Wolfram Sang <[email protected]> Tested-by: Archit Taneja <[email protected]> Signed-off-by: Thong Ho <[email protected]> Signed-off-by: Nhan Nguyen <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/gpu/drm/i2c/adv7511.c | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-) --- a/drivers/gpu/drm/i2c/adv7511.c +++ b/drivers/gpu/drm/i2c/adv7511.c @@ -362,12 +362,19 @@ static void adv7511_power_on(struct adv7 { adv7511->current_edid_segment = -1; - regmap_write(adv7511->regmap, ADV7511_REG_INT(0), - ADV7511_INT0_EDID_READY); - regmap_write(adv7511->regmap, ADV7511_REG_INT(1), - ADV7511_INT1_DDC_ERROR); regmap_update_bits(adv7511->regmap, ADV7511_REG_POWER, ADV7511_POWER_POWER_DOWN, 0); + if (adv7511->i2c_main->irq) { + /* + * Documentation says the INT_ENABLE registers are reset in + * POWER_DOWN mode. My 7511w preserved the bits, however. + * Still, let's be safe and stick to the documentation. + */ + regmap_write(adv7511->regmap, ADV7511_REG_INT_ENABLE(0), + ADV7511_INT0_EDID_READY); + regmap_write(adv7511->regmap, ADV7511_REG_INT_ENABLE(1), + ADV7511_INT1_DDC_ERROR); + } /* * Per spec it is allowed to pulse the HDP signal to indicate that the @@ -567,12 +574,14 @@ static int adv7511_get_modes(struct drm_ /* Reading the EDID only works if the device is powered */ if (!adv7511->powered) { - regmap_write(adv7511->regmap, ADV7511_REG_INT(0), - ADV7511_INT0_EDID_READY); - regmap_write(adv7511->regmap, ADV7511_REG_INT(1), - ADV7511_INT1_DDC_ERROR); regmap_update_bits(adv7511->regmap, ADV7511_REG_POWER, ADV7511_POWER_POWER_DOWN, 0); + if (adv7511->i2c_main->irq) { + regmap_write(adv7511->regmap, ADV7511_REG_INT_ENABLE(0), + ADV7511_INT0_EDID_READY); + regmap_write(adv7511->regmap, ADV7511_REG_INT_ENABLE(1), + ADV7511_INT1_DDC_ERROR); + } adv7511->current_edid_segment = -1; }
