The EC reports a variety of error codes. Most of those, with the exception of EC_RES_INVALID_VERSION, are converted to -EPROTO. As result, the actual error code gets lost. In cros_ec_cmd_xfer_status(), convert all EC errors to Linux error codes to report a more meaningful error to the caller to aid debugging. To prepare for this change, handle error codes other than -EPROTO for all callers of cros_ec_cmd_xfer_status(). Specifically, no longer assume that -EPROTO reflects an error from the EC and all other error codes reflect a transfer error. v2: Add patches 1/4 to 3/4 to handle callers of cros_ec_cmd_xfer_status() v3: Add patches 4/6 and 5/6 to handle additional callers of cros_ec_cmd_xfer_status() Use -ENOPROTOOPT for EC_RES_INVALID_VERSION Implement function to convert error codes v4: Add coments describing the functionality of cros_ec_num_pwms(). Add patch 7/7 to clean up cros_ec_num_pwms() after the new error code support has been implemented. Rebased series to v5.8. v5: If there is no error, cros_ec_cmd_xfer_status() needs to return the number of received bytes, not 0. While fixing that (in patch 6/7), rearranged the function to reduce its indentation. Rebased series to v5.9-rc1 ---------------------------------------------------------------- Guenter Roeck (7): iio: cros_ec: Accept -EOPNOTSUPP as 'not supported' error code cros_ec_lightbar: Accept more error codes from cros_ec_cmd_xfer_status platform/chrome: cros_ec_sysfs: Report range of error codes from EC pwm: cros-ec: Accept more error codes from cros_ec_cmd_xfer_status platform/input: cros_ec: Replace -ENOTSUPP with -ENOPROTOOPT platform/chrome: cros_ec_proto: Convert EC error codes to Linux error codes pwm: cros-ec: Simplify EC error handling .../iio/common/cros_ec_sensors/cros_ec_sensors.c | 2 +- drivers/input/keyboard/cros_ec_keyb.c | 2 +- drivers/platform/chrome/cros_ec_lightbar.c | 10 ++-- drivers/platform/chrome/cros_ec_proto.c | 57 +++++++++++++++++----- drivers/platform/chrome/cros_ec_sysfs.c | 24 ++++----- drivers/pwm/pwm-cros-ec.c | 37 +++++++------- 6 files changed, 78 insertions(+), 54 deletions(-)