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| author | Alex Deucher <alexander.deucher@amd.com> | 2012-01-20 23:50:18 +0400 |
|---|---|---|
| committer | Dave Airlie <airlied@redhat.com> | 2012-02-03 13:38:05 +0400 |
| commit | 30388c6e48e62b2806b14552275f091e2f5adbf4 (patch) | |
| tree | 304ba513a92d61a4943392df4b35b306add5cc07 /drivers/gpu/drm/radeon/radeon_i2c.c | |
| parent | 9048955748aa14b1dbf068ef3a9288ec15cabc66 (diff) | |
| download | linux-30388c6e48e62b2806b14552275f091e2f5adbf4.tar.xz | |
drm/radeon/kms/dce3+: add support for hw i2c using atom
Starting with DCE3 hardware, atom contains a general purpose
ProcessI2cChannelTransaction similar to ProcessAuxChannelTransaction.
Add an implementation using the atom tables for DCE3+ hardware.
This should be a little less CPU intensive than bit banging and
may work better in certain cases.
Enable it by setting the radeon hw_i2c module parameter to 1. E.g.,
radeon.hw_i2c=1
on the kernel command line in grub.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Diffstat (limited to 'drivers/gpu/drm/radeon/radeon_i2c.c')
| -rw-r--r-- | drivers/gpu/drm/radeon/radeon_i2c.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/drivers/gpu/drm/radeon/radeon_i2c.c b/drivers/gpu/drm/radeon/radeon_i2c.c index c47f222f7442..3265a7a57977 100644 --- a/drivers/gpu/drm/radeon/radeon_i2c.c +++ b/drivers/gpu/drm/radeon/radeon_i2c.c @@ -30,6 +30,10 @@ #include "radeon.h" #include "atom.h" +extern int radeon_atom_hw_i2c_xfer(struct i2c_adapter *i2c_adap, + struct i2c_msg *msgs, int num); +extern u32 radeon_atom_hw_i2c_func(struct i2c_adapter *adap); + /** * radeon_ddc_probe * @@ -882,6 +886,11 @@ static const struct i2c_algorithm radeon_i2c_algo = { .functionality = radeon_hw_i2c_func, }; +static const struct i2c_algorithm radeon_atom_i2c_algo = { + .master_xfer = radeon_atom_hw_i2c_xfer, + .functionality = radeon_atom_hw_i2c_func, +}; + struct radeon_i2c_chan *radeon_i2c_create(struct drm_device *dev, struct radeon_i2c_bus_rec *rec, const char *name) @@ -914,6 +923,18 @@ struct radeon_i2c_chan *radeon_i2c_create(struct drm_device *dev, DRM_ERROR("Failed to register hw i2c %s\n", name); goto out_free; } + } else if (rec->hw_capable && + radeon_hw_i2c && + ASIC_IS_DCE3(rdev)) { + /* hw i2c using atom */ + snprintf(i2c->adapter.name, sizeof(i2c->adapter.name), + "Radeon i2c hw bus %s", name); + i2c->adapter.algo = &radeon_atom_i2c_algo; + ret = i2c_add_adapter(&i2c->adapter); + if (ret) { + DRM_ERROR("Failed to register hw i2c %s\n", name); + goto out_free; + } } else { /* set the radeon bit adapter */ snprintf(i2c->adapter.name, sizeof(i2c->adapter.name), |