4.18-stable review patch. If anyone has any objections, please let me know.
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From: Hans de Goede hdegoede@redhat.com
[ Upstream commit 0a30446c0dca3483c384b54a431cc951e15f7e79 ]
Currently acpi_gsb_i2c_read_bytes() directly returns i2c_transfer's return value. i2c_transfer returns a value < 0 on error and 2 (for 2 successfully executed transfers) on success. But the ACPI code expects 0 on success, so currently acpi_gsb_i2c_read_bytes()'s caller does:
if (status > 0) status = 0;
This commit makes acpi_gsb_i2c_read_bytes() return a value which can be directly consumed by the ACPI code, mirroring acpi_gsb_i2c_write_bytes(), this commit also makes acpi_gsb_i2c_read_bytes() explitcly check that i2c_transfer returns 2, rather then accepting any value > 0.
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 Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/i2c/i2c-core-acpi.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
--- a/drivers/i2c/i2c-core-acpi.c +++ b/drivers/i2c/i2c-core-acpi.c @@ -453,8 +453,12 @@ static int acpi_gsb_i2c_read_bytes(struc else dev_err(&client->adapter->dev, "i2c read %d bytes from client@%#x starting at reg %#x failed, error: %d\n", data_len, client->addr, cmd, ret); - } else { + /* 2 transfers must have completed successfully */ + } else if (ret == 2) { memcpy(data, buffer, data_len); + ret = 0; + } else { + ret = -EIO; }
kfree(buffer); @@ -595,8 +599,6 @@ i2c_acpi_space_handler(u32 function, acp if (action == ACPI_READ) { status = acpi_gsb_i2c_read_bytes(client, command, gsb->data, info->access_length); - if (status > 0) - status = 0; } else { status = acpi_gsb_i2c_write_bytes(client, command, gsb->data, info->access_length);