Re: [alsa-devel] [RFC PATCH 15/40] soundwire: cadence_master: handle multiple status reports per Slave

Pierre-Louis Bossart
2019-07-26T14:10:01Z

>> diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c
>> index 889fa2cd49ae..25d5c7267c15 100644
>> --- a/drivers/soundwire/cadence_master.c
>> +++ b/drivers/soundwire/cadence_master.c
>> @@ -643,13 +643,35 @@ static int cdns_update_slave_status(struct sdw_cdns *cdns,
>>
>> /* first check if Slave reported multiple status */
>> if (set_status > 1) {
>> + u32 val;
>> +
>> dev_warn_ratelimited(cdns->dev,
>> - "Slave reported multiple Status: %d\n",
>> - mask);
>> - /*
>> - * TODO: we need to reread the status here by
>> - * issuing a PING cmd
>> - */
>> + "Slave %d reported multiple Status: %d\n",
>> + i, mask);
>> +
>> + /* re-check latest status extracted from PING commands */
>> + val = cdns_readl(cdns, CDNS_MCP_SLAVE_STAT);
>> + val >>= (i * 2);
>
> Superfluous parentheses.

Humm, I don't know my left from my right and I can't remember operator
precedence, so i'd rather make it explicit...

>
>> +
>> + switch (val & 0x3) {
>> + case 0:
>> + status[i] = SDW_SLAVE_UNATTACHED;
>> + break;
>> + case 1:
>> + status[i] = SDW_SLAVE_ATTACHED;
>> + break;
>> + case 2:
>> + status[i] = SDW_SLAVE_ALERT;
>> + break;
>> + default:
>
> There aren't many values left for the "default" case :-) But I'm not sure whether
> any of
>
> + case 3:
>
> or
>
> + case 3:
> + default:
>
> would improve readability.
>
> Thanks
> Guennadi
>
>> + status[i] = SDW_SLAVE_RESERVED;
>> + break;

Yes, those defaults are annoying. Some tools complain so I tend to leave
them.