From: Pierre-Louis Bossart <[email protected]> In case the clock needs to keep running, we need to prevent the Master from entering pm_runtime suspend.
Signed-off-by: Pierre-Louis Bossart <[email protected]> Signed-off-by: Bard Liao <[email protected]> --- drivers/soundwire/intel.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index 744fc0a4816a..c9d8de65cfd6 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -1366,6 +1366,7 @@ int intel_master_startup(struct platform_device *pdev) struct sdw_intel *sdw = cdns_to_intel(cdns); struct sdw_bus *bus = &cdns->bus; int link_flags; + u32 clock_stop_quirks; int ret; if (bus->prop.hw_disabled) { @@ -1422,6 +1423,20 @@ int intel_master_startup(struct platform_device *pdev) pm_runtime_enable(dev); } + clock_stop_quirks = sdw->link_res->clock_stop_quirks; + if (clock_stop_quirks & SDW_INTEL_CLK_STOP_NOT_ALLOWED) { + /* + * To keep the clock running we need to prevent + * pm_runtime suspend from happening by increasing the + * reference count. + * This quirk is specified by the parent PCI device in + * case of specific latency requirements. It will have + * no effect if pm_runtime is disabled by the user via + * a module parameter for testing purposes. + */ + pm_runtime_get_noresume(dev); + } + /* * The runtime PM status of Slave devices is "Unsupported" * until they report as ATTACHED. If they don't, e.g. because @@ -1453,6 +1468,11 @@ static int intel_master_remove(struct platform_device *pdev) struct sdw_intel *sdw = cdns_to_intel(cdns); struct sdw_bus *bus = &cdns->bus; + /* + * Since pm_runtime is already disabled, we don't decrease + * the refcount when the clock_stop_quirk is + * SDW_INTEL_CLK_STOP_NOT_ALLOWED + */ if (!bus->prop.hw_disabled) { intel_debugfs_exit(sdw); sdw_cdns_enable_interrupt(cdns, false); -- 2.17.1
