diff options
| author | Ville Syrjälä <ville.syrjala@linux.intel.com> | 2017-11-23 21:41:56 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-12-05 11:22:51 +0100 |
| commit | e6bcff7b6aa1c0fb30234864821e8169eeb8054d (patch) | |
| tree | 3b1a56ce2b71cd9d90e743be37e642be7c6c0c2d /drivers | |
| parent | a61474fa8749f67ef18aa2104b48b0b56ea654b7 (diff) | |
drm/i915: Don't try indexed reads to alternate slave addresses
commit ae5c631e605a452a5a0e73205a92810c01ed954b upstream.
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: 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -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 f3bee54c414f..ce625496ce01 100644 --- a/drivers/gpu/drm/i915/intel_i2c.c +++ b/drivers/gpu/drm/i915/intel_i2c.c @@ -440,6 +440,7 @@ 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)); } |