The open coded version differs from the one in the core in one way: the
buffer will be always copied back, even when the transfer failed. It
looks like it is expected that the sanity check for a correct CRC and
header will bail out later.
Use the block read from the I2C core and propagate a potential errno
further to the sanity check.
Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
---
Note: we could now make the error checking even stronger by checking if
the number of received bytes is I2C_SMBUS_BLOCK_MAX. But to avoid
regressions, I kept the logic as is, i.e. only check for errno.
drivers/media/i2c/adv7511-v4l2.c | 40 +++++++++++---------------------
1 file changed, 14 insertions(+), 26 deletions(-)
diff --git a/drivers/media/i2c/adv7511-v4l2.c b/drivers/media/i2c/adv7511-v4l2.c
index a3161d709015..0150f76dc6a6 100644
--- a/drivers/media/i2c/adv7511-v4l2.c
+++ b/drivers/media/i2c/adv7511-v4l2.c
@@ -214,36 +214,24 @@ static inline void adv7511_wr_and_or(struct v4l2_subdev *sd, u8 reg, u8 clr_mask
adv7511_wr(sd, reg, (adv7511_rd(sd, reg) & clr_mask) | val_mask);
}
-static int adv_smbus_read_i2c_block_data(struct i2c_client *client,
- u8 command, unsigned length, u8 *values)
-{
- union i2c_smbus_data data;
- int ret;
-
- if (length > I2C_SMBUS_BLOCK_MAX)
- length = I2C_SMBUS_BLOCK_MAX;
- data.block[0] = length;
-
- ret = i2c_smbus_xfer(client->adapter, client->addr, client->flags,
- I2C_SMBUS_READ, command,
- I2C_SMBUS_I2C_BLOCK_DATA, &data);
- memcpy(values, data.block + 1, length);
- return ret;
-}
-
-static void adv7511_edid_rd(struct v4l2_subdev *sd, uint16_t len, uint8_t *buf)
+static int adv7511_edid_rd(struct v4l2_subdev *sd, uint16_t len, uint8_t *buf)
{
struct adv7511_state *state = get_adv7511_state(sd);
+ s32 len;
int i;
- int err = 0;
v4l2_dbg(1, debug, sd, "%s:\n", __func__);
- for (i = 0; !err && i < len; i += I2C_SMBUS_BLOCK_MAX)
- err = adv_smbus_read_i2c_block_data(state->i2c_edid, i,
+ for (i = 0; i < len; i += I2C_SMBUS_BLOCK_MAX) {
+ len = i2c_smbus_read_i2c_block_data(state->i2c_edid, i,
I2C_SMBUS_BLOCK_MAX, buf + i);
- if (err)
- v4l2_err(sd, "%s: i2c read error\n", __func__);
+ if (len < 0) {
+ v4l2_err(sd, "%s: i2c read error\n", __func__);
+ return len;
+ }
+ }
+
+ return 0;
}
static inline int adv7511_cec_read(struct v4l2_subdev *sd, u8 reg)
@@ -1668,20 +1656,20 @@ static bool adv7511_check_edid_status(struct v4l2_subdev *sd)
if (edidRdy & MASK_ADV7511_EDID_RDY) {
int segment = adv7511_rd(sd, 0xc4);
struct adv7511_edid_detect ed;
+ int err;
if (segment >= EDID_MAX_SEGM) {
v4l2_err(sd, "edid segment number too big\n");
return false;
}
v4l2_dbg(1, debug, sd, "%s: got segment %d\n", __func__, segment);
- adv7511_edid_rd(sd, 256, &state->edid.data[segment * 256]);
+ err = adv7511_edid_rd(sd, 256, &state->edid.data[segment * 256]);
adv7511_dbg_dump_edid(2, debug, sd, segment, &state->edid.data[segment * 256]);
if (segment == 0) {
state->edid.blocks = state->edid.data[0x7e] + 1;
v4l2_dbg(1, debug, sd, "%s: %d blocks in total\n", __func__, state->edid.blocks);
}
- if (!edid_verify_crc(sd, segment) ||
- !edid_verify_header(sd, segment)) {
+ if (err < 0 || !edid_verify_crc(sd, segment) || !edid_verify_header(sd, segment)) {
/* edid crc error, force reread of edid segment */
v4l2_err(sd, "%s: edid crc or header error\n", __func__);
state->have_monitor = false;
--
2.29.2
