On 7/29/20 3:21 PM, Brian Norris wrote:
> Hi Guenter,
>
> On Sun, Jul 26, 2020 at 03:01:01PM -0700, Guenter Roeck wrote:
>> v3: Use -ENOPROTOOPT for EC_RES_INVALID_VERSION
>> Implement function to convert error codes
>> v2: No change
>>
>> drivers/platform/chrome/cros_ec_proto.c | 52 ++++++++++++++++++++-----
>> 1 file changed, 42 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c
>> index e5bbec979a2a..a081b8245682 100644
>> --- a/drivers/platform/chrome/cros_ec_proto.c
>> +++ b/drivers/platform/chrome/cros_ec_proto.c
>> @@ -15,6 +15,43 @@
>>
>> #define EC_COMMAND_RETRIES 50
>>
>> +static const int cros_ec_error_map[] = {
>> + [EC_RES_INVALID_COMMAND] = -EOPNOTSUPP,
>> + [EC_RES_ERROR] = -EIO,
>> + [EC_RES_INVALID_PARAM] = -EINVAL,
>> + [EC_RES_ACCESS_DENIED] = -EACCES,
>> + [EC_RES_INVALID_RESPONSE] = -EPROTO,
>> + [EC_RES_INVALID_VERSION] = -ENOPROTOOPT,
>> + [EC_RES_INVALID_CHECKSUM] = -EBADMSG,
>> + [EC_RES_IN_PROGRESS] = -EINPROGRESS,
>> + [EC_RES_UNAVAILABLE] = -ENODATA,
>> + [EC_RES_TIMEOUT] = -ETIMEDOUT,
>> + [EC_RES_OVERFLOW] = -EOVERFLOW,
>> + [EC_RES_INVALID_HEADER] = -EBADR,
>> + [EC_RES_REQUEST_TRUNCATED] = -EBADR,
>> + [EC_RES_RESPONSE_TOO_BIG] = -EFBIG,
>> + [EC_RES_BUS_ERROR] = -EFAULT,
>> + [EC_RES_BUSY] = -EBUSY,
>> + [EC_RES_INVALID_HEADER_VERSION] = -EBADMSG,
>> + [EC_RES_INVALID_HEADER_CRC] = -EBADMSG,
>> + [EC_RES_INVALID_DATA_CRC] = -EBADMSG,
>> + [EC_RES_DUP_UNAVAILABLE] = -ENODATA,
>> +};
>
> Sorry I didn't pay attention to this earlier, but is there any
> programmatic way to ensure that we don't have unexpected holes here? If
> we do (e.g., we add new error codes, but they aren't contiguous for
> whatever reasons), then those will get treated as "success" with your
> current patch.
>
> I say "unexpected" hole, because EC_RES_SUCCESS (0) is an expected hole.
>
>> +
>> +static int cros_ec_map_error(uint32_t result)
>> +{
>> + int ret = 0;
>> +
>> + if (result != EC_RES_SUCCESS) {
>> + if (result < ARRAY_SIZE(cros_ec_error_map) && cros_ec_error_map[result])
>> + ret = cros_ec_error_map[result];
>
> ^^ Maybe we want to double check 'ret != 0'? Or maybe
>
> ret = cros_ec_error_map[result];
> if (!ret) {
'ret' won't ever be 0 here. Above:
&& cros_ec_error_map[result]
and below:
else
ret = -EPROTO;
> ret = -EPROTO;
> dev_err(..., "Unexpected EC result code %d\n", result);
> }
>
> ? Could even be WARN_ON(), since this would be an actionable programming
> error, not exactly an external factor. Or maybe I'm being paranoid, and
> future programmers are perfect.
>
I think, if anything, we might consider adding the message below (result >=
ARRAY_SIZE(cros_ec_error_map) is just as bad). Not sure myself. I am
open to adding it if people think it would be useful/desirable.
Thanks,
Guenter
> Otherwise:
>
> Reviewed-by: Brian Norris <briannorris@xxxxxxxxxxxx>
>
>> + else
>> + ret = -EPROTO;
>> + }
>> +
>> + return ret;
>> +}
>> +
>> static int prepare_packet(struct cros_ec_device *ec_dev,
>> struct cros_ec_command *msg)
>> {
