From 533a8a67cc3b072a24122d1ea10a8db66a5c9393 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 28 Apr 2025 21:50:07 +0200 Subject: [PATCH] soundwire: intel_auxdevice: Fix system suspend/resume handling Before commit bca84a7b93fd ("PM: sleep: Use DPM_FLAG_SMART_SUSPEND conditionally") the runtime PM status of the device in intel_resume() had always been RPM_ACTIVE because setting DPM_FLAG_SMART_SUSPEND had caused the core to call pm_runtime_set_active() for that device during the "noirq" resume phase. For this reason, the pm_runtime_suspended() check in intel_resume() had never triggered and the code depending on it had never run. That had not caused any observable functional issues to appear, so effectively the code in question had never been needed. After commit bca84a7b93fd the core does not call pm_runtime_set_active() for all devices with DPM_FLAG_SMART_SUSPEND set any more and the code depending on the pm_runtime_suspended() check in intel_resume() runs if the device is runtime-suspended prior to a system-wide suspend transition. Unfortunately, when it runs, it breaks things due to the attempt to runtime-resume bus->dev which most likely is not ready for a runtime resume at that point. It also does other more-or-less questionable things. Namely, it calls pm_runtime_idle() for a device with a nonzero runtime PM usage counter which has no effect (all devices have nonzero runtime PM usage counters during system-wide suspend and resume). It also calls pm_runtime_mark_last_busy() for the device even though devices cannot runtime-suspend during system-wide suspend and resume (because their runtime PM usage counters are nonzero) and an analogous call is made in the same function later. Moreover, it sets the runtime PM status of the device to RPM_ACTIVE before activating it. For the reasons listed above, remove that code altogether. On top of that, add a pm_runtime_disable() call to intel_suspend() to prevent the device from being runtime-resumed at any point after intel_suspend() has started to manipulate it because the changes made by that function would be undone by a runtime-suspend of the device. Next, once runtime PM has been disabled, the runtime PM status of the device cannot change, so pm_runtime_status_suspended() can be used instead of pm_runtime_suspended() in intel_suspend(). Finally, make intel_resume() call pm_runtime_set_active() at the end to set the runtime PM status of the device to "active" because it has just been activated and re-enable runtime PM for it after that. Additionally, drop the setting of DPM_FLAG_SMART_SUSPEND from the driver because it has no effect on devices handled by it. Fixes: bca84a7b93fd ("PM: sleep: Use DPM_FLAG_SMART_SUSPEND conditionally") Reported-by: Bard Liao Tested-by: Bard Liao Signed-off-by: Rafael J. Wysocki Acked-by: Bard Liao Link: https://patch.msgid.link/12680420.O9o76ZdvQC@rjwysocki.net --- drivers/soundwire/intel_auxdevice.c | 36 +++++++++++------------------ 1 file changed, 13 insertions(+), 23 deletions(-) diff --git a/drivers/soundwire/intel_auxdevice.c b/drivers/soundwire/intel_auxdevice.c index 5ea6399e6c9b..10a602d4843a 100644 --- a/drivers/soundwire/intel_auxdevice.c +++ b/drivers/soundwire/intel_auxdevice.c @@ -353,9 +353,6 @@ static int intel_link_probe(struct auxiliary_device *auxdev, /* use generic bandwidth allocation algorithm */ sdw->cdns.bus.compute_params = sdw_compute_params; - /* avoid resuming from pm_runtime suspend if it's not required */ - dev_pm_set_driver_flags(dev, DPM_FLAG_SMART_SUSPEND); - ret = sdw_bus_master_add(bus, dev, dev->fwnode); if (ret) { dev_err(dev, "sdw_bus_master_add fail: %d\n", ret); @@ -640,7 +637,10 @@ static int __maybe_unused intel_suspend(struct device *dev) return 0; } - if (pm_runtime_suspended(dev)) { + /* Prevent runtime PM from racing with the code below. */ + pm_runtime_disable(dev); + + if (pm_runtime_status_suspended(dev)) { dev_dbg(dev, "pm_runtime status: suspended\n"); clock_stop_quirks = sdw->link_res->clock_stop_quirks; @@ -648,7 +648,7 @@ static int __maybe_unused intel_suspend(struct device *dev) if ((clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET) || !clock_stop_quirks) { - if (pm_runtime_suspended(dev->parent)) { + if (pm_runtime_status_suspended(dev->parent)) { /* * paranoia check: this should not happen with the .prepare * resume to full power @@ -715,7 +715,6 @@ static int __maybe_unused 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 || !sdw->startup_done) { @@ -724,23 +723,6 @@ static int __maybe_unused intel_resume(struct device *dev) return 0; } - if (pm_runtime_suspended(dev)) { - dev_dbg(dev, "pm_runtime status was suspended, forcing active\n"); - - /* follow required sequence from runtime_pm.rst */ - pm_runtime_disable(dev); - pm_runtime_set_active(dev); - pm_runtime_mark_last_busy(dev); - pm_runtime_enable(dev); - - pm_runtime_resume(bus->dev); - - link_flags = md_flags >> (bus->link_id * 8); - - if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE)) - pm_runtime_idle(dev); - } - ret = sdw_intel_link_power_up(sdw); if (ret) { dev_err(dev, "%s failed: %d\n", __func__, ret); @@ -760,6 +742,14 @@ static int __maybe_unused intel_resume(struct device *dev) return ret; } + /* + * Runtime PM has been disabled in intel_suspend(), so set the status + * to active because the device has just been resumed and re-enable + * runtime PM. + */ + pm_runtime_set_active(dev); + pm_runtime_enable(dev); + /* * after system resume, the pm_runtime suspend() may kick in * during the enumeration, before any children device force the -- 2.25.1