From: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com
Add quirk and pm_runtime idle scheduling to let the Master suspend if no Slaves become attached. This can happen when a link is not marked as disabled and has devices exposed in the DSDT, if the power is controlled by sideband means or the link includes a pluggable connector.
Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Signed-off-by: Rander Wang rander.wang@linux.intel.com Signed-off-by: Bard Liao yung-chuan.liao@linux.intel.com --- drivers/soundwire/intel.c | 26 ++++++++++++++++++++++++-- 1 file changed, 24 insertions(+), 2 deletions(-)
diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index 95a1d88a5bfb..3f9015dcb693 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -31,8 +31,9 @@ * flags reused in each byte, with master0 using the ls-byte, etc. */
-#define SDW_INTEL_MASTER_DISABLE_PM_RUNTIME BIT(0) -#define SDW_INTEL_MASTER_DISABLE_CLOCK_STOP BIT(1) +#define SDW_INTEL_MASTER_DISABLE_PM_RUNTIME BIT(0) +#define SDW_INTEL_MASTER_DISABLE_CLOCK_STOP BIT(1) +#define SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE BIT(2)
static int md_flags; module_param_named(sdw_md_flags, md_flags, int, 0444); @@ -1422,6 +1423,22 @@ int intel_master_startup(struct platform_device *pdev) pm_runtime_enable(dev); }
+ /* + * The runtime PM status of Slave devices is "Unsupported" + * until they report as ATTACHED. If they don't, e.g. because + * there are no Slave devices populated or if the power-on is + * delayed or dependent on a power switch, the Master will + * remain active and prevent its parent from suspending. + * + * Conditionally force the pm_runtime core to re-evaluate the + * Master status in the absence of any Slave activity. A quirk + * is provided to e.g. deal with Slaves that may be powered on + * with a delay. A more complete solution would require the + * definition of Master properties. + */ + if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE)) + pm_runtime_idle(dev); + return 0;
err_interrupt: @@ -1561,6 +1578,7 @@ static int intel_resume(struct device *dev) struct sdw_cdns *cdns = dev_get_drvdata(dev); struct sdw_intel *sdw = cdns_to_intel(cdns); struct sdw_bus *bus = &cdns->bus; + int link_flags; int ret;
if (bus->prop.hw_disabled) { @@ -1577,6 +1595,10 @@ static int intel_resume(struct device *dev) pm_runtime_set_active(dev); pm_runtime_mark_last_busy(dev); pm_runtime_enable(dev); + + link_flags = md_flags >> (bus->link_id * 8); + if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE)) + pm_runtime_idle(dev); }
ret = intel_init(sdw);