Re: [PATCH 09/13] soundwire: intel: add CLK_STOP_BUS_RESET support

[Vinod Koul <vkoul@kernel.org>]

On 22-07-20, 04:37, Bard Liao wrote:
> From: Rander Wang <rander.wang@intel.com>
> 
> Move existing pm_runtime suspend under the CLK_STOP_TEARDOWN case.
> 
> In this mode the Master IP will lose all context but in-band wakes are
> supported.
> 
> On pm_runtime resume a complete re-enumeration will be performed after
> a bus reset.
> 
> Signed-off-by: Rander Wang <rander.wang@intel.com>
> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
> Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
> ---
>  drivers/soundwire/intel.c | 44 +++++++++++++++++++++++++++++++++++++++
>  1 file changed, 44 insertions(+)
> 
> diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c
> index 1954eb48b86c..744fc0a4816a 100644
> --- a/drivers/soundwire/intel.c
> +++ b/drivers/soundwire/intel.c
> @@ -1576,6 +1576,26 @@ static int intel_suspend_runtime(struct device *dev)
>  
>  		intel_shim_wake(sdw, false);
>  
> +	} else if (clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET) {
> +		ret = sdw_cdns_clock_stop(cdns, true);
> +		if (ret < 0) {
> +			dev_err(dev, "cannot enable clock stop on suspend\n");
> +			return ret;
> +		}
> +
> +		ret = sdw_cdns_enable_interrupt(cdns, false);
> +		if (ret < 0) {
> +			dev_err(dev, "cannot disable interrupts on suspend\n");
> +			return ret;
> +		}
> +
> +		ret = intel_link_power_down(sdw);
> +		if (ret) {
> +			dev_err(dev, "Link power down failed: %d", ret);
> +			return ret;
> +		}

no cleanup on all the error cases here?

> +
> +		intel_shim_wake(sdw, true);
>  	} else {
>  		dev_err(dev, "%s clock_stop_quirks %x unsupported\n",
>  			__func__, clock_stop_quirks);
> @@ -1694,6 +1714,30 @@ static int intel_resume_runtime(struct device *dev)
>  			dev_err(dev, "unable to exit bus reset sequence during resume\n");
>  			return ret;
>  		}
> +	} else if (clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET) {
> +		ret = intel_init(sdw);
> +		if (ret) {
> +			dev_err(dev, "%s failed: %d", __func__, ret);
> +			return ret;
> +		}
> +
> +		/*
> +		 * make sure all Slaves are tagged as UNATTACHED and
> +		 * provide reason for reinitialization
> +		 */
> +		sdw_clear_slave_status(bus, SDW_UNATTACH_REQUEST_MASTER_RESET);
> +
> +		ret = sdw_cdns_enable_interrupt(cdns, true);
> +		if (ret < 0) {
> +			dev_err(dev, "cannot enable interrupts during resume\n");
> +			return ret;
> +		}
> +
> +		ret = sdw_cdns_clock_restart(cdns, true);
> +		if (ret < 0) {
> +			dev_err(dev, "unable to restart clock during resume\n");
> +			return ret;
> +		}
>  	} else {
>  		dev_err(dev, "%s clock_stop_quirks %x unsupported\n",
>  			__func__, clock_stop_quirks);
> -- 
> 2.17.1

-- 
~Vinod