From c074c39d62306efa5ba7c69c1a1531bc7333d252 Mon Sep 17 00:00:00 2001 From: Jean Delvare <khali@linux-fr.org> Date: Sat, 13 Mar 2010 20:56:53 +0100 Subject: [PATCH] i2c-i801: Don't use the block buffer for I2C block writes Experience has shown that the block buffer can only be used for SMBus (not I2C) block transactions, even though the datasheet doesn't mention this limitation. Reported-by: Felix Rubinstein <felixru@gmail.com> Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Oleg Ryjkov <oryjkov@gmail.com> Cc: stable@kernel.org --- drivers/i2c/busses/i2c-i801.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c index 9da5b05cdb528b..299b918455a369 100644 --- a/drivers/i2c/busses/i2c-i801.c +++ b/drivers/i2c/busses/i2c-i801.c @@ -416,9 +416,11 @@ static int i801_block_transaction(union i2c_smbus_data *data, char read_write, data->block[0] = 32; /* max for SMBus block reads */ } + /* Experience has shown that the block buffer can only be used for + SMBus (not I2C) block transactions, even though the datasheet + doesn't mention this limitation. */ if ((i801_features & FEATURE_BLOCK_BUFFER) - && !(command == I2C_SMBUS_I2C_BLOCK_DATA - && read_write == I2C_SMBUS_READ) + && command != I2C_SMBUS_I2C_BLOCK_DATA && i801_set_block_buffer_mode() == 0) result = i801_block_transaction_by_block(data, read_write, hwpec); -- GitLab