Re: [PATCH V3 8/8] soundwire: amd: add pm_prepare callback and pm ops support

+static int amd_resume_child_device(struct device *dev, void *data) +{

• int ret;
• struct sdw_slave *slave = dev_to_sdw_dev(dev);

style: invert two lines?

• if (!slave->probed) {

• dev_dbg(dev, "skipping device, no probed driver\n");
  

• return 0;
  

• }
• if (!slave->dev_num_sticky) {

• dev_dbg(dev, "skipping device, never detected on bus\n");
  

• return 0;
  

• }
• if (!pm_runtime_suspended(dev))

• return 0;
  

• ret = pm_request_resume(dev);

why not resume unconditionally and let the pm_runtime framework figure things out?

That's what we did for Intel...

• if (ret < 0)

• dev_err(dev, "pm_request_resume failed: %d\n", ret);
  

• return ret;

+}

+static int __maybe_unused amd_pm_prepare(struct device *dev) +{

• struct amd_sdw_manager *amd_manager = dev_get_drvdata(dev);
• struct sdw_bus *bus = &amd_manager->bus;
• int ret;
• if (bus->prop.hw_disabled) {

• dev_dbg(bus->dev, "SoundWire manager %d is disabled, ignoring\n",
  

• 	bus->link_id);
  

• return 0;
  

• }
• /*

• * When multiple peripheral devices connected over the same link, if SoundWire manager
  

• * device is not in runtime suspend state, observed that device alerts are missing
  

• * without pm_prepare on AMD platforms in clockstop mode0.
  

• */
  

• if (pm_runtime_suspended(dev) && amd_manager->power_mode_mask & AMD_SDW_CLK_STOP_MODE) {

• ret = pm_request_resume(dev);
  

same, why not simplify and use:

if (amd_manager->power_mode_mask & AMD_SDW_CLK_STOP_MODE) { ret = pm_request_resume(dev);

• if (ret < 0) {
  

• 	dev_err(bus->dev, "pm_request_resume failed: %d\n", ret);
  

• 	return 0;
  

• }
  

• }
• /* To force peripheral devices to system level suspend state, resume the devices

• * from runtime suspend state first. Without that unable to dispatch the alert
  

• * status to peripheral driver during system level resume as they are in runtime
  

• * suspend state.
  

• */
  

• ret = device_for_each_child(bus->dev, NULL, amd_resume_child_device);
• if (ret < 0)

• dev_err(dev, "amd_resume_child_device failed: %d\n", ret);
  

• return 0;

+}

+static int __maybe_unused amd_suspend(struct device *dev) +{

• struct amd_sdw_manager *amd_manager = dev_get_drvdata(dev);
• struct sdw_bus *bus = &amd_manager->bus;
• int ret;
• if (bus->prop.hw_disabled) {

• dev_dbg(bus->dev, "SoundWire manager %d is disabled, ignoring\n",
  

• 	bus->link_id);
  

• return 0;
  

• }
• if (amd_manager->power_mode_mask & AMD_SDW_CLK_STOP_MODE) {

• ret = amd_sdw_clock_stop(amd_manager);
  

• if (ret)
  

• 	return ret;
  

you could do a return amd_sdw_clock_stop(amd_manager);

• } else if (amd_manager->power_mode_mask & AMD_SDW_POWER_OFF_MODE) {

• /*
  

•  * As per hardware programming sequence on AMD platforms,
  

•  * clock stop should be invoked first before powering-off
  

•  */
  

• ret = amd_sdw_clock_stop(amd_manager);
  

• if (ret)
  

• 	return ret;
  

• ret = amd_deinit_sdw_manager(amd_manager);
  

• if (ret)
  

• 	return ret;
  

• }
• return 0;

+}