diff options
| author | Ville Syrjälä <ville.syrjala@linux.intel.com> | 2017-11-23 21:41:56 +0200 |
|---|---|---|
| committer | Sasha Levin <alexander.levin@verizon.com> | 2017-12-08 18:01:17 -0500 |
| commit | b504b57060a2f285de5393dabfc64d71d654e748 (patch) | |
| tree | 50f9dbe09a7b107518bd99f506f7740182f7b686 | |
| parent | 27460f85f87ee7ff8abe5a6e548928835ac2f471 (diff) | |
drm/i915: Don't try indexed reads to alternate slave addresses
[ Upstream commit ae5c631e605a452a5a0e73205a92810c01ed954b ]
We can only specify the one slave address to indexed reads/writes.
Make sure the messages we check are destined to the same slave
address before deciding to do an indexed transfer.
Cc: stable@vger.kernel.org
Cc: Daniel Kurtz <djkurtz@chromium.org>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Sean Paul <seanpaul@chromium.org>
Fixes: 56f9eac05489 ("drm/i915/intel_i2c: use INDEX cycles for i2c read transactions")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171123194157.25367-2-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
(cherry picked from commit c4deb62d7821672265b87952bcd1c808f3bf3e8f)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
| -rw-r--r-- | drivers/gpu/drm/i915/intel_i2c.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_i2c.c b/drivers/gpu/drm/i915/intel_i2c.c index ae628001fd97..6f3b747eeda5 100644 --- a/drivers/gpu/drm/i915/intel_i2c.c +++ b/drivers/gpu/drm/i915/intel_i2c.c @@ -394,6 +394,7 @@ static bool gmbus_is_index_read(struct i2c_msg *msgs, int i, int num) { return (i + 1 < num && + msgs[i].addr == msgs[i + 1].addr && !(msgs[i].flags & I2C_M_RD) && msgs[i].len <= 2 && (msgs[i + 1].flags & I2C_M_RD)); } |