PM: domains: Add flags to specify power on attach/detach

Calling dev_pm_domain_attach()/dev_pm_domain_detach() in bus driver
probe/remove functions can affect system behavior when the drivers
attached to the bus use devres-managed resources. Since devres actions
may need to access device registers, calling dev_pm_domain_detach() too
early, i.e., before these actions complete, can cause failures on some
systems. One such example is Renesas RZ/G3S SoC-based platforms.

If the device clocks are managed via PM domains, invoking
dev_pm_domain_detach() in the bus driver's remove function removes the
device's clocks from the PM domain, preventing any subsequent
pm_runtime_resume*() calls from enabling those clocks.

The second argument of dev_pm_domain_attach() specifies whether the PM
domain should be powered on during attachment. Likewise, the second
argument of dev_pm_domain_detach() indicates whether the domain should be
powered off during detachment.

Upcoming changes address the issue described above (initially for the
platform bus only) by deferring the call to dev_pm_domain_detach() until
after devres_release_all() in device_unbind_cleanup(). The detach_power_off
field in struct dev_pm_info stores the detach power off info from the
second argument of dev_pm_domain_attach().

Because there are cases where the device's PM domain power-on/off behavior
must be conditional (e.g., in i2c_device_probe()), the patch introduces
PD_FLAG_ATTACH_POWER_ON and PD_FLAG_DETACH_POWER_OFF flags to be passed
to dev_pm_domain_attach().

Finally, dev_pm_domain_attach() and its users are updated to use the newly
introduced PD_FLAG_ATTACH_POWER_ON and PD_FLAG_DETACH_POWER_OFF macros.

This change is preparatory.

Signed-off-by: Claudiu Beznea <[e-mail]>
Reviewed-by: Mathieu Poirier <[e-mail]>
Acked-by: Wolfram Sang <[e-mail]> # I2C
Reviewed-by: Ulf Hansson <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
[ rjw: Changelog adjustments ]
Signed-off-by: Rafael J. Wysocki <[e-mail]>

drivers/amba/bus.c

···
 	void __iomem *tmp;
 	int i, ret;
 
-	ret = dev_pm_domain_attach(&dev->dev, true);
+	ret = dev_pm_domain_attach(&dev->dev, PD_FLAG_ATTACH_POWER_ON);
 	if (ret) {
 		dev_dbg(&dev->dev, "can't get PM domain: %d\n", ret);
 		goto err_out;
···
 		if (ret < 0)
 			break;
 
-		ret = dev_pm_domain_attach(dev, true);
+		ret = dev_pm_domain_attach(dev, PD_FLAG_ATTACH_POWER_ON);
 		if (ret)
 			break;
 

drivers/base/auxiliary.c

···
 	struct auxiliary_device *auxdev = to_auxiliary_dev(dev);
 	int ret;
 
-	ret = dev_pm_domain_attach(dev, true);
+	ret = dev_pm_domain_attach(dev, PD_FLAG_ATTACH_POWER_ON);
 	if (ret) {
 		dev_warn(dev, "Failed to attach to PM Domain : %d\n", ret);
 		return ret;

drivers/base/platform.c

···
 	if (ret < 0)
 		return ret;
 
-	ret = dev_pm_domain_attach(_dev, true);
+	ret = dev_pm_domain_attach(_dev, PD_FLAG_ATTACH_POWER_ON);
 	if (ret)
 		goto out;
 

drivers/base/power/common.c

···
 /**
  * dev_pm_domain_attach - Attach a device to its PM domain.
  * @dev: Device to attach.
- * @power_on: Used to indicate whether we should power on the device.
+ * @flags: indicate whether we should power on/off the device on attach/detach
  *
  * The @dev may only be attached to a single PM domain. By iterating through
  * the available alternatives we try to find a valid PM domain for the device.
···
  * Returns 0 on successfully attached PM domain, or when it is found that the
  * device doesn't need a PM domain, else a negative error code.
  */
-int dev_pm_domain_attach(struct device *dev, bool power_on)
+int dev_pm_domain_attach(struct device *dev, u32 flags)
 {
 	int ret;
 
 	if (dev->pm_domain)
 		return 0;
 
-	ret = acpi_dev_pm_attach(dev, power_on);
+	ret = acpi_dev_pm_attach(dev, !!(flags & PD_FLAG_ATTACH_POWER_ON));
 	if (!ret)
 		ret = genpd_dev_pm_attach(dev);
 

drivers/clk/qcom/apcs-sdx55.c

···
 	 * driver, there seems to be no better place to do this. So do it here!
 	 */
 	cpu_dev = get_cpu_device(0);
-	ret = dev_pm_domain_attach(cpu_dev, true);
+	ret = dev_pm_domain_attach(cpu_dev, PD_FLAG_ATTACH_POWER_ON);
 	if (ret) {
 		dev_err_probe(dev, ret, "can't get PM domain: %d\n", ret);
 		goto err;

drivers/gpu/drm/display/drm_dp_aux_bus.c

···
 		container_of(aux_ep, struct dp_aux_ep_device_with_data, aux_ep);
 	int ret;
 
-	ret = dev_pm_domain_attach(dev, true);
+	ret = dev_pm_domain_attach(dev, PD_FLAG_ATTACH_POWER_ON);
 	if (ret)
 		return dev_err_probe(dev, ret, "Failed to attach to PM Domain\n");
 

drivers/i2c/i2c-core-base.c

···
 		goto err_clear_wakeup_irq;
 
 	do_power_on = !i2c_acpi_waive_d0_probe(dev);
-	status = dev_pm_domain_attach(&client->dev, do_power_on);
+	status = dev_pm_domain_attach(&client->dev, do_power_on ? PD_FLAG_ATTACH_POWER_ON : 0);
 	if (status)
 		goto err_clear_wakeup_irq;
 

drivers/mmc/core/sdio_bus.c

···
 	if (!id)
 		return -ENODEV;
 
-	ret = dev_pm_domain_attach(dev, false);
+	ret = dev_pm_domain_attach(dev, 0);
 	if (ret)
 		return ret;
 

drivers/rpmsg/rpmsg_core.c

···
 	struct rpmsg_endpoint *ept = NULL;
 	int err;
 
-	err = dev_pm_domain_attach(dev, true);
+	err = dev_pm_domain_attach(dev, PD_FLAG_ATTACH_POWER_ON);
 	if (err)
 		goto out;
 

drivers/soundwire/bus_type.c

···
 	/*
 	 * attach to power domain but don't turn on (last arg)
 	 */
-	ret = dev_pm_domain_attach(dev, false);
+	ret = dev_pm_domain_attach(dev, 0);
 	if (ret)
 		return ret;
 

drivers/spi/spi.c

···
 	if (spi->irq < 0)
 		spi->irq = 0;
 
-	ret = dev_pm_domain_attach(dev, true);
+	ret = dev_pm_domain_attach(dev, PD_FLAG_ATTACH_POWER_ON);
 	if (ret)
 		return ret;
 

drivers/tty/serdev/core.c

···
 	const struct serdev_device_driver *sdrv = to_serdev_device_driver(dev->driver);
 	int ret;
 
-	ret = dev_pm_domain_attach(dev, true);
+	ret = dev_pm_domain_attach(dev, PD_FLAG_ATTACH_POWER_ON);
 	if (ret)
 		return ret;
 

include/linux/pm_domain.h

···
  *				isn't specified, the index just follows the
  *				index for the attached PM domain.
  *
+ * PD_FLAG_ATTACH_POWER_ON:	Power on the domain during attach.
+ *
+ * PD_FLAG_DETACH_POWER_OFF:	Power off the domain during detach.
+ *
  */
 #define PD_FLAG_NO_DEV_LINK		BIT(0)
 #define PD_FLAG_DEV_LINK_ON		BIT(1)
 #define PD_FLAG_REQUIRED_OPP		BIT(2)
+#define PD_FLAG_ATTACH_POWER_ON		BIT(3)
+#define PD_FLAG_DETACH_POWER_OFF	BIT(4)
 
 struct dev_pm_domain_attach_data {
 	const char * const *pd_names;
···
 #endif /* CONFIG_PM_GENERIC_DOMAINS_OF */
 
 #ifdef CONFIG_PM
-int dev_pm_domain_attach(struct device *dev, bool power_on);
+int dev_pm_domain_attach(struct device *dev, u32 flags);
 struct device *dev_pm_domain_attach_by_id(struct device *dev,
 					  unsigned int index);
 struct device *dev_pm_domain_attach_by_name(struct device *dev,
···
 void dev_pm_domain_set(struct device *dev, struct dev_pm_domain *pd);
 int dev_pm_domain_set_performance_state(struct device *dev, unsigned int state);
 #else
-static inline int dev_pm_domain_attach(struct device *dev, bool power_on)
+static inline int dev_pm_domain_attach(struct device *dev, u32 flags)
 {
 	return 0;
 }