On 11-03-20, 13:41, Pierre-Louis Bossart wrote:
> From: Rander Wang <rander.wang@xxxxxxxxx>
>
> If master is in clock stop state, driver can't modify registers
> in master except the registers for clock stop setting.
>
> Signed-off-by: Rander Wang <rander.wang@xxxxxxxxx>
> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
> ---
> drivers/soundwire/cadence_master.c | 19 +++++++++++++++++++
> drivers/soundwire/cadence_master.h | 2 ++
> 2 files changed, 21 insertions(+)
>
> diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c
> index 941809ea00a8..71cba2585151 100644
> --- a/drivers/soundwire/cadence_master.c
> +++ b/drivers/soundwire/cadence_master.c
> @@ -1207,6 +1207,25 @@ static const struct sdw_master_port_ops cdns_port_ops = {
> .dpn_port_enable_ch = cdns_port_enable,
> };
>
> +/**
> + * sdw_cdns_is_clock_stop: Check clock status
> + *
> + * @cdns: Cadence instance
> + */
> +bool sdw_cdns_is_clock_stop(struct sdw_cdns *cdns)
> +{
> + u32 status;
> +
> + status = cdns_readl(cdns, CDNS_MCP_STAT) & CDNS_MCP_STAT_CLK_STOP;
> + if (status) {
> + dev_dbg(cdns->dev, "Clock is stopped\n");
> + return true;
> + }
This can be further optimized to:
return !!(cdns_readl(cdns, CDNS_MCP_STAT) & CDNS_MCP_STAT_CLK_STOP);
--
~Vinod
