drm/udl: Reading all edid blocks in DRM/UDL driver

Now DRM/UDL driver retreives all edid data blocks instead of only base one.
Previous approch could lead to improper initialization of video mode with
certain monitors.

Signed-off-by: Robert Tarasov <tutankhamen@chromium.org>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171013001350.172155-2-tutankhamen@chromium.org
This commit is contained in:
Robert Tarasov 2017-10-12 17:13:50 -07:00 committed by Alex Deucher
parent afdfc4c6f5
commit 75c65ee20a

View File

@ -17,42 +17,79 @@
#include "udl_connector.h"
#include "udl_drv.h"
/* dummy connector to just get EDID,
all UDL appear to have a DVI-D */
static u8 *udl_get_edid(struct udl_device *udl)
static bool udl_get_edid_block(struct udl_device *udl, int block_idx,
u8 *buff)
{
u8 *block;
char *rbuf;
int ret, i;
u8 *read_buff;
block = kmalloc(EDID_LENGTH, GFP_KERNEL);
if (block == NULL)
return NULL;
rbuf = kmalloc(2, GFP_KERNEL);
if (rbuf == NULL)
goto error;
read_buff = kmalloc(2, GFP_KERNEL);
if (!read_buff)
return false;
for (i = 0; i < EDID_LENGTH; i++) {
int bval = (i + block_idx * EDID_LENGTH) << 8;
ret = usb_control_msg(udl->udev,
usb_rcvctrlpipe(udl->udev, 0), (0x02),
(0x80 | (0x02 << 5)), i << 8, 0xA1, rbuf, 2,
HZ);
usb_rcvctrlpipe(udl->udev, 0),
(0x02), (0x80 | (0x02 << 5)), bval,
0xA1, read_buff, 2, HZ);
if (ret < 1) {
DRM_ERROR("Read EDID byte %d failed err %x\n", i, ret);
goto error;
kfree(read_buff);
return false;
}
block[i] = rbuf[1];
buff[i] = read_buff[1];
}
kfree(rbuf);
return block;
kfree(read_buff);
return true;
}
error:
kfree(block);
kfree(rbuf);
return NULL;
static bool udl_get_edid(struct udl_device *udl, u8 **result_buff,
int *result_buff_size)
{
int i, extensions;
u8 *block_buff = NULL, *buff_ptr;
block_buff = kmalloc(EDID_LENGTH, GFP_KERNEL);
if (block_buff == NULL)
return false;
if (udl_get_edid_block(udl, 0, block_buff) &&
memchr_inv(block_buff, 0, EDID_LENGTH)) {
extensions = ((struct edid *)block_buff)->extensions;
if (extensions > 0) {
/* we have to read all extensions one by one */
*result_buff_size = EDID_LENGTH * (extensions + 1);
*result_buff = kmalloc(*result_buff_size, GFP_KERNEL);
buff_ptr = *result_buff;
if (buff_ptr == NULL) {
kfree(block_buff);
return false;
}
memcpy(buff_ptr, block_buff, EDID_LENGTH);
kfree(block_buff);
buff_ptr += EDID_LENGTH;
for (i = 1; i < extensions; ++i) {
if (udl_get_edid_block(udl, i, buff_ptr)) {
buff_ptr += EDID_LENGTH;
} else {
kfree(*result_buff);
*result_buff = NULL;
return false;
}
}
return true;
}
/* we have only base edid block */
*result_buff = block_buff;
*result_buff_size = EDID_LENGTH;
return true;
}
kfree(block_buff);
return false;
}
static int udl_get_modes(struct drm_connector *connector)
@ -84,33 +121,26 @@ static int udl_mode_valid(struct drm_connector *connector,
static enum drm_connector_status
udl_detect(struct drm_connector *connector, bool force)
{
struct edid *edid;
u8 *edid_buff = NULL;
int edid_buff_size = 0;
struct udl_device *udl = connector->dev->dev_private;
struct udl_drm_connector *udl_connector =
container_of(connector,
struct udl_drm_connector,
connector);
/* cleanup previous edid */
if (udl_connector->edid != NULL) {
kfree(udl_connector->edid);
udl_connector->edid = NULL;
}
edid = (struct edid *)udl_get_edid(udl);
if (!edid || !memchr_inv(edid, 0, EDID_LENGTH))
if (!udl_get_edid(udl, &edid_buff, &edid_buff_size))
return connector_status_disconnected;
udl_connector->edid = edid;
/*
* We only read the main block, but if the monitor reports extension
* blocks then the drm edid code expects them to be present, so patch
* the extension count to 0.
*/
udl_connector->edid->checksum +=
udl_connector->edid->extensions;
udl_connector->edid->extensions = 0;
udl_connector->edid = (struct edid *)edid_buff;
return connector_status_connected;
}