The hw i2c engines are disabled by default as the current implementation is still experimental. Print a warning when users enable it so that it's obvious when the option is enabled.
Signed-off-by: Alex Deucher alexander.deucher@amd.com Cc: stable@vger.kernel.org --- drivers/gpu/drm/radeon/radeon_i2c.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/gpu/drm/radeon/radeon_i2c.c b/drivers/gpu/drm/radeon/radeon_i2c.c index fc60b74..74bfbf8 100644 --- a/drivers/gpu/drm/radeon/radeon_i2c.c +++ b/drivers/gpu/drm/radeon/radeon_i2c.c @@ -1020,6 +1020,9 @@ void radeon_i2c_destroy(struct radeon_i2c_chan *i2c) /* Add the default buses */ void radeon_i2c_init(struct radeon_device *rdev) { + if (radeon_hw_i2c == 1) + DRM_INFO("hw_i2c forced on, you may experience display detection problems!\n"); + if (rdev->is_atom_bios) radeon_atombios_i2c_init(rdev); else
Am 07.01.2014 16:14, schrieb Alex Deucher:
The hw i2c engines are disabled by default as the current implementation is still experimental. Print a warning when users enable it so that it's obvious when the option is enabled.
Signed-off-by: Alex Deucher alexander.deucher@amd.com Cc: stable@vger.kernel.org
Reviewed-by: Christian König christian.koenig@amd.com
drivers/gpu/drm/radeon/radeon_i2c.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/gpu/drm/radeon/radeon_i2c.c b/drivers/gpu/drm/radeon/radeon_i2c.c index fc60b74..74bfbf8 100644 --- a/drivers/gpu/drm/radeon/radeon_i2c.c +++ b/drivers/gpu/drm/radeon/radeon_i2c.c @@ -1020,6 +1020,9 @@ void radeon_i2c_destroy(struct radeon_i2c_chan *i2c) /* Add the default buses */ void radeon_i2c_init(struct radeon_device *rdev) {
- if (radeon_hw_i2c == 1)
DRM_INFO("hw_i2c forced on, you may experience display detection problems!\n");- if (rdev->is_atom_bios) radeon_atombios_i2c_init(rdev); else
On 07.01.2014 16:14, Alex Deucher wrote:
The hw i2c engines are disabled by default as the current implementation is still experimental. Print a warning when users enable it so that it's obvious when the option is enabled.
Does hardware I2C actually have any advantage in the DDC use case? AFAICT it's only transferring small amounts of data and mostly on display connect events, so not very often.
Best regards Grigori
On Tue, Jan 7, 2014 at 10:58 AM, Grigori Goronzy greg@chown.ath.cx wrote:
On 07.01.2014 16:14, Alex Deucher wrote:
The hw i2c engines are disabled by default as the current implementation is still experimental. Print a warning when users enable it so that it's obvious when the option is enabled.
Does hardware I2C actually have any advantage in the DDC use case? AFAICT it's only transferring small amounts of data and mostly on display connect events, so not very often.
It's lower CPU usage compared to bit-banging and can generate interrupts if you want to do something else while it fetches the EDID.
Alex
2014/1/7 Alex Deucher alexdeucher@gmail.com:
if (radeon_hw_i2c == 1)DRM_INFO("hw_i2c forced on, you may experience display detection problems!\n");
What about simple if (radeon_hw_i2c) ? Values 2, 3, ... also enable i2c.
On Tue, Jan 7, 2014 at 11:16 AM, Rafał Miłecki zajec5@gmail.com wrote:
2014/1/7 Alex Deucher alexdeucher@gmail.com:
if (radeon_hw_i2c == 1)DRM_INFO("hw_i2c forced on, you may experience display detection problems!\n");What about simple if (radeon_hw_i2c) ? Values 2, 3, ... also enable i2c.
Updated patch sent. thanks!
Alex
dri-devel@lists.freedesktop.org
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Alex Deucher -
Christian König -
Grigori Goronzy -
Rafał Miłecki