Commits
Hans de Goede committed c463a158cb6
i2c: core: ACPI: Properly set status byte to 0 for multi-byte writes
acpi_gsb_i2c_write_bytes() returns i2c_transfer()'s return value, which
is the number of transfers executed on success, so 1.
The ACPI code expects us to store 0 in gsb->status for success, not 1.
Specifically this breaks the following code in the Thinkpad 8 DSDT:
ECWR = I2CW = ECWR /* \_SB_.I2C1.BAT0.ECWR */
If ((ECST == Zero))
{
ECRD = I2CR /* \_SB_.I2C1.I2CR */
}
Before this commit we set ECST to 1, causing the read to never happen
breaking battery monitoring on the Thinkpad 8.
This commit makes acpi_gsb_i2c_write_bytes() return 0 when i2c_transfer()
returns 1, so the single write transfer completed successfully, and
makes it return -EIO on for other (unexpected) return values >= 0.
Cc: stable@vger.kernel.org
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>