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authorAlex Deucher <alexdeucher@gmail.com>2009-11-11 05:25:07 +0300
committerDave Airlie <airlied@redhat.com>2009-12-02 04:36:40 +0300
commitfcec570b27a47e428a9bfc8572ae4c7c230d0488 (patch)
tree10cbff0900c7de4b0cd6c83df5cc220d5844b8a9 /drivers/gpu/drm/radeon/radeon_i2c.c
parent9b9fe72488a3a637e0550cc888e3f7a8f70e521e (diff)
downloadlinux-fcec570b27a47e428a9bfc8572ae4c7c230d0488.tar.xz
drm/radeon/kms: add support for external tmds on legacy boards
This enables initialization of external tmds chips on pre-atom and mac systems. Macs are untested. Also, some macs have single link tmds chips while others have dual link tmds chips. We need to figure out which ones have which. This gets external TMDS working on my RS485 and RV380. Signed-off-by: Alex Deucher <alexdeucher@gmail.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.c56
1 files changed, 56 insertions, 0 deletions
diff --git a/drivers/gpu/drm/radeon/radeon_i2c.c b/drivers/gpu/drm/radeon/radeon_i2c.c
index e97a3912d99f..6c645fb4dad8 100644
--- a/drivers/gpu/drm/radeon/radeon_i2c.c
+++ b/drivers/gpu/drm/radeon/radeon_i2c.c
@@ -212,3 +212,59 @@ struct drm_encoder *radeon_best_encoder(struct drm_connector *connector)
{
return NULL;
}
+
+void radeon_i2c_sw_get_byte(struct radeon_i2c_chan *i2c_bus,
+ u8 slave_addr,
+ u8 addr,
+ u8 *val)
+{
+ u8 out_buf[2];
+ u8 in_buf[2];
+ struct i2c_msg msgs[] = {
+ {
+ .addr = slave_addr,
+ .flags = 0,
+ .len = 1,
+ .buf = out_buf,
+ },
+ {
+ .addr = slave_addr,
+ .flags = I2C_M_RD,
+ .len = 1,
+ .buf = in_buf,
+ }
+ };
+
+ out_buf[0] = addr;
+ out_buf[1] = 0;
+
+ if (i2c_transfer(&i2c_bus->adapter, msgs, 2) == 2) {
+ *val = in_buf[0];
+ DRM_DEBUG("val = 0x%02x\n", *val);
+ } else {
+ DRM_ERROR("i2c 0x%02x 0x%02x read failed\n",
+ addr, *val);
+ }
+}
+
+void radeon_i2c_sw_put_byte(struct radeon_i2c_chan *i2c_bus,
+ u8 slave_addr,
+ u8 addr,
+ u8 val)
+{
+ uint8_t out_buf[2];
+ struct i2c_msg msg = {
+ .addr = slave_addr,
+ .flags = 0,
+ .len = 2,
+ .buf = out_buf,
+ };
+
+ out_buf[0] = addr;
+ out_buf[1] = val;
+
+ if (i2c_transfer(&i2c_bus->adapter, &msg, 1) != 1)
+ DRM_ERROR("i2c 0x%02x 0x%02x write failed\n",
+ addr, val);
+}
+