Currently reading EDID only works because usually only two EDID blocks
of 128 bytes is used. Where an EDID segment holds 256 bytes or two EDID
blocks. And the first EDID segment read works fine but E-EDID specifies
up to 128 segments.
The logic is broken so change EDID segment index to multiple of 256
bytes and not 128 (block size).
Also change check of DDC status. Instead of silently not reading EDID
when in "IDLE" state [1]. Check if the DDC controller is in reset
instead (no HPD).
[1]
ADV7511 Programming Guide: Table 11: DDCController Status:
0xC8 [3:0] DDC Controller State
0000 In Reset (No Hot Plug Detected)
0001 Reading EDID
0010 IDLE (Waiting for HDCP Requested)
0011 Initializing HDCP
0100 HDCP Enabled
0101 Initializing HDCP Repeater
Signed-off-by: Emil Svendsen <emas@xxxxxxxxxxxxxxx>
---
drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 24 ++++++++++++--------
1 file changed, 15 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
index 8be235144f6d..c641c2ccd412 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
@@ -537,6 +537,8 @@ static int adv7511_get_edid_block(void *data, u8 *buf, unsigned int block,
size_t len)
{
struct adv7511 *adv7511 = data;
+ struct device* dev = &adv7511->i2c_edid->dev;
+ int edid_segment = block / 2;
struct i2c_msg xfer[2];
uint8_t offset;
unsigned int i;
@@ -545,7 +547,7 @@ static int adv7511_get_edid_block(void *data, u8 *buf, unsigned int block,
if (len > 128)
return -EINVAL;
- if (adv7511->current_edid_segment != block / 2) {
+ if (adv7511->current_edid_segment != edid_segment) {
unsigned int status;
ret = regmap_read(adv7511->regmap, ADV7511_REG_DDC_STATUS,
@@ -553,15 +555,19 @@ static int adv7511_get_edid_block(void *data, u8 *buf, unsigned int block,
if (ret < 0)
return ret;
- if (status != 2) {
- adv7511->edid_read = false;
- regmap_write(adv7511->regmap, ADV7511_REG_EDID_SEGMENT,
- block);
- ret = adv7511_wait_for_edid(adv7511, 200);
- if (ret < 0)
- return ret;
+ if (!(status & 0x0F)) {
+ dev_dbg(dev, "DDC in reset no hot plug detected %x\n",
+ status);
+ return -EIO;
}
+ adv7511->edid_read = false;
+ regmap_write(adv7511->regmap, ADV7511_REG_EDID_SEGMENT,
+ edid_segment);
+ ret = adv7511_wait_for_edid(adv7511, 200);
+ if (ret < 0)
+ return ret;
+
/* Break this apart, hopefully more I2C controllers will
* support 64 byte transfers than 256 byte transfers
*/
@@ -589,7 +595,7 @@ static int adv7511_get_edid_block(void *data, u8 *buf, unsigned int block,
offset += 64;
}
- adv7511->current_edid_segment = block / 2;
+ adv7511->current_edid_segment = edid_segment;
}
if (block % 2 == 0)
--
2.34.1
