From 5786e2c5a3f519647c50bbc276e45d36a704415a Mon Sep 17 00:00:00 2001 From: Alex Deucher Date: Thu, 19 Aug 2010 11:19:31 -0400 Subject: [PATCH] drm/radeon/kms/DCE3+: switch pads to ddc mode when going i2c The pins for ddc and aux are shared so you need to switch the mode when doing ddc. The ProcessAuxChannel table already sets the pin mode to DP. This should fix unreliable ddc issues on DP ports using non-DP monitors. Signed-off-by: Alex Deucher Cc: stable@kernel.org Signed-off-by: Dave Airlie --- drivers/gpu/drm/radeon/radeon_i2c.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/gpu/drm/radeon/radeon_i2c.c b/drivers/gpu/drm/radeon/radeon_i2c.c index bfd2ce5f5372..0416804d8f30 100644 --- a/drivers/gpu/drm/radeon/radeon_i2c.c +++ b/drivers/gpu/drm/radeon/radeon_i2c.c @@ -99,6 +99,13 @@ static void radeon_i2c_do_lock(struct radeon_i2c_chan *i2c, int lock_state) } } + /* switch the pads to ddc mode */ + if (ASIC_IS_DCE3(rdev) && rec->hw_capable) { + temp = RREG32(rec->mask_clk_reg); + temp &= ~(1 << 16); + WREG32(rec->mask_clk_reg, temp); + } + /* clear the output pin values */ temp = RREG32(rec->a_clk_reg) & ~rec->a_clk_mask; WREG32(rec->a_clk_reg, temp);