This is a note to let you know that I've just added the patch titled soundwire: cadence: only prepare attached devices on clock stop to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: soundwire-cadence-only-prepare-attached-devices-on-c.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 0be5a959b52464b6adfdfc93418b320c1496061d Author: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx> Date: Tue Mar 23 09:37:07 2021 +0800 soundwire: cadence: only prepare attached devices on clock stop [ Upstream commit 58ef9356260c291a4321e07ff507f31a1d8212af ] We sometimes see COMMAND_IGNORED responses during the clock stop sequence. It turns out we already have information if devices are present on a link, so we should only prepare those when they are attached. In addition, even when COMMAND_IGNORED are received, we should still proceed with the clock stop. The device will not be prepared but that's not a problem. The only case where the clock stop will fail is if the Cadence IP reports an error (including a timeout), or if the devices throw a COMMAND_FAILED response. BugLink: https://github.com/thesofproject/linux/issues/2621 Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx> Reviewed-by: Rander Wang <rander.wang@xxxxxxxxx> Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@xxxxxxxxxxxxxxx> Signed-off-by: Bard Liao <yung-chuan.liao@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20210323013707.21455-1-yung-chuan.liao@xxxxxxxxxxxxxxx Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c index 580660599f46..c6d421a4b91b 100644 --- a/drivers/soundwire/cadence_master.c +++ b/drivers/soundwire/cadence_master.c @@ -1449,10 +1449,12 @@ int sdw_cdns_clock_stop(struct sdw_cdns *cdns, bool block_wake) } /* Prepare slaves for clock stop */ - ret = sdw_bus_prep_clk_stop(&cdns->bus); - if (ret < 0) { - dev_err(cdns->dev, "prepare clock stop failed %d", ret); - return ret; + if (slave_present) { + ret = sdw_bus_prep_clk_stop(&cdns->bus); + if (ret < 0 && ret != -ENODATA) { + dev_err(cdns->dev, "prepare clock stop failed %d\n", ret); + return ret; + } } /*