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. Be more robust: use the block read from the I2C core and propagate a potential errno further to the sanity checks. Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx> --- Changes since v1: * respect 'err' in more code paths * updated comment drivers/media/i2c/adv7511-v4l2.c | 58 ++++++++++++++------------------ 1 file changed, 26 insertions(+), 32 deletions(-) diff --git a/drivers/media/i2c/adv7511-v4l2.c b/drivers/media/i2c/adv7511-v4l2.c index a3161d709015..9183003ae22d 100644 --- a/drivers/media/i2c/adv7511-v4l2.c +++ b/drivers/media/i2c/adv7511-v4l2.c @@ -214,36 +214,25 @@ 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); 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) { + s32 ret; + + ret = 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 (ret < 0) { + v4l2_err(sd, "%s: i2c read error\n", __func__); + return ret; + } + } + + return 0; } static inline int adv7511_cec_read(struct v4l2_subdev *sd, u8 reg) @@ -1668,22 +1657,27 @@ 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]); - 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); + err = adv7511_edid_rd(sd, 256, &state->edid.data[segment * 256]); + if (!err) { + 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)) { - /* edid crc error, force reread of edid segment */ - v4l2_err(sd, "%s: edid crc or header error\n", __func__); + + if (err || !edid_verify_crc(sd, segment) || !edid_verify_header(sd, segment)) { + /* Couldn't read EDID or EDID is invalid. Force retry! */ + if (!err) + v4l2_err(sd, "%s: edid crc or header error\n", __func__); state->have_monitor = false; adv7511_s_power(sd, false); adv7511_s_power(sd, true); -- 2.28.0