Hi Nickey,
On 22-02-2017 11:11, Nickey.Yang wrote:
> Read EDID func is drm_do_probe_ddc_edid (in
> drivers/gpu/drm/drm_edid.c Line:1215)
> when block = 3 means &msgs[3].addr = DDC_SEGMENT_ADDR(0x30)
> ,but in dw_hdmi_i2c_xfer
> line 299 msgs[i].addr != addr (0x50), it will printk
> "unsupported transfer, changed slave address"
> and return -EOPNOTSUPP.
>
> in fact,0x30 not means change slave address but means segment
> address.
>
I am reading the drm_do_probe_ddc_edid and I have one question:
There are 2 writes and one read, but your patch only handles the
write of segment address. What about the start address?
I am refering to this structure:
1228 struct i2c_msg msgs[] = {
1229 {
1230 .addr = DDC_SEGMENT_ADDR,
1231 .flags = 0,
1232 .len = 1,
1233 .buf = &segment,
1234 }, {
1235 .addr = DDC_ADDR,
1236 .flags = 0,
1237 .len = 1,
1238 .buf = &start,
1239 }, {
1240 .addr = DDC_ADDR,
1241 .flags = I2C_M_RD,
1242 .len = len,
1243 .buf = buf,
1244 }
There is a write which indicates DDC segment address and then
there is another write which indicates start address. Shouldn't
this be handled?
Best regards,
Jose Miguel Abreu
