i2c: tegra: fix maximum transfer size

commit f4e3f4ae1d9c9330de355f432b69952e8cef650c upstream.

Tegra186 and prior supports maximum 4K bytes per packet transfer
including 12 bytes of packet header.

This patch fixes max write length limit to account packet header
size for transfers.

Cc: stable@vger.kernel.org # 4.4+
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 586e557e113a593aa5858766f62dd8cfdfa7fd46..36100f453f314e095dba183ce8c6cf11188fcb3b 100644 (file)
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -794,7 +794,7 @@ static const struct i2c_algorithm tegra_i2c_algo = {
 /* payload size is only 12 bit */
 static struct i2c_adapter_quirks tegra_i2c_quirks = {
        .max_read_len = 4096,
-       .max_write_len = 4096,
+       .max_write_len = 4096 - 12,
 };
 
 static const struct tegra_i2c_hw_feature tegra20_i2c_hw = {