platform/x86: thinkpad_acpi: Move subdriver initialization to tpacpi_pdriver's probe.

It was reported that if subdrivers assigned devres resources inside
ibm_init_struct's .init callbacks, driver binding would fail with the
following error message:

	platform thinkpad_acpi: Resources present before probing

Let the driver core manage the lifetimes of the subdrivers and children
devices, by initializing them inside tpacpi_driver's .probe callback.
This is appropriate because these subdrivers usually expose sysfs groups
and the driver core manages this automatically to avoid races.

One immediate benefit of this, is that we are now able to use devres
inside .init subdriver callbacks.

platform_create_bundle is specifically used because it makes the
driver's probe type synchronous and returns an ERR_PTR if attachment
failed.

Additionally, to make error handling simpler, allocate the input device
using devm_input_allocate_device().

Reported-by: Mark Pearson <[email protected]>
Closes: https://lore.kernel.org/platform-driver-x86/[email protected]/#t
Reviewed-by: Mark Pearson <[email protected]>
Tested-by: Mark Pearson <[email protected]>
Signed-off-by: Kurt Borja <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Ilpo Järvinen <[email protected]>

Author: kuu-rt

drivers/platform/x86/thinkpad_acpi.c

@@ -367,8 +367,6 @@ static struct {
 	u32 beep_needs_two_args:1;
 	u32 mixer_no_level_control:1;
 	u32 battery_force_primary:1;
-	u32 input_device_registered:1;
-	u32 platform_drv_registered:1;
 	u32 sensors_pdrv_registered:1;
 	u32 hotkey_poll_active:1;
 	u32 has_adaptive_kbd:1;
@@ -11815,36 +11813,20 @@ MODULE_PARM_DESC(profile_force, "Force profile mode. -1=off, 1=MMC, 2=PSC");
 
 static void thinkpad_acpi_module_exit(void)
 {
-	struct ibm_struct *ibm, *itmp;
-
 	tpacpi_lifecycle = TPACPI_LIFE_EXITING;
 
 	if (tpacpi_hwmon)
 		hwmon_device_unregister(tpacpi_hwmon);
 	if (tp_features.sensors_pdrv_registered)
 		platform_driver_unregister(&tpacpi_hwmon_pdriver);
-	if (tp_features.platform_drv_registered)
-		platform_driver_unregister(&tpacpi_pdriver);
-
-	list_for_each_entry_safe_reverse(ibm, itmp,
-					 &tpacpi_all_drivers,
-					 all_drivers) {
-		ibm_exit(ibm);
-	}
-
-	dbg_printk(TPACPI_DBG_INIT, "finished subdriver exit path...\n");
-
-	if (tpacpi_inputdev) {
-		if (tp_features.input_device_registered)
-			input_unregister_device(tpacpi_inputdev);
-		else
-			input_free_device(tpacpi_inputdev);
-	}
-
 	if (tpacpi_sensors_pdev)
 		platform_device_unregister(tpacpi_sensors_pdev);
-	if (tpacpi_pdev)
+
+	if (tpacpi_pdev) {
+		platform_driver_unregister(&tpacpi_pdriver);
 		platform_device_unregister(tpacpi_pdev);
+	}
+
 	if (proc_dir)
 		remove_proc_entry(TPACPI_PROC_DIR, acpi_root_dir);
 	if (tpacpi_wq)
@@ -11856,11 +11838,63 @@ static void thinkpad_acpi_module_exit(void)
 	kfree(thinkpad_id.nummodel_str);
 }
 
+static void tpacpi_subdrivers_release(void *data)
+{
+	struct ibm_struct *ibm, *itmp;
+
+	list_for_each_entry_safe_reverse(ibm, itmp, &tpacpi_all_drivers, all_drivers)
+		ibm_exit(ibm);
+
+	dbg_printk(TPACPI_DBG_INIT, "finished subdriver exit path...\n");
+}
+
+static int __init tpacpi_pdriver_probe(struct platform_device *pdev)
+{
+	int ret;
+
+	devm_mutex_init(&pdev->dev, &tpacpi_inputdev_send_mutex);
+
+	tpacpi_inputdev = devm_input_allocate_device(&pdev->dev);
+	if (!tpacpi_inputdev)
+		return -ENOMEM;
+
+	tpacpi_inputdev->name = "ThinkPad Extra Buttons";
+	tpacpi_inputdev->phys = TPACPI_DRVR_NAME "/input0";
+	tpacpi_inputdev->id.bustype = BUS_HOST;
+	tpacpi_inputdev->id.vendor = thinkpad_id.vendor;
+	tpacpi_inputdev->id.product = TPACPI_HKEY_INPUT_PRODUCT;
+	tpacpi_inputdev->id.version = TPACPI_HKEY_INPUT_VERSION;
+	tpacpi_inputdev->dev.parent = &tpacpi_pdev->dev;
+
+	/* Init subdriver dependencies */
+	tpacpi_detect_brightness_capabilities();
+
+	/* Init subdrivers */
+	for (unsigned int i = 0; i < ARRAY_SIZE(ibms_init); i++) {
+		ret = ibm_init(&ibms_init[i]);
+		if (ret >= 0 && *ibms_init[i].param)
+			ret = ibms_init[i].data->write(ibms_init[i].param);
+		if (ret < 0) {
+			tpacpi_subdrivers_release(NULL);
+			return ret;
+		}
+	}
+
+	ret = devm_add_action_or_reset(&pdev->dev, tpacpi_subdrivers_release, NULL);
+	if (ret)
+		return ret;
+
+	ret = input_register_device(tpacpi_inputdev);
+	if (ret < 0)
+		pr_err("unable to register input device\n");
+
+	return ret;
+}
 
 static int __init thinkpad_acpi_module_init(void)
 {
 	const struct dmi_system_id *dmi_id;
-	int ret, i;
+	int ret;
 	acpi_object_type obj_type;
 
 	tpacpi_lifecycle = TPACPI_LIFE_INIT;
@@ -11920,15 +11954,16 @@ static int __init thinkpad_acpi_module_init(void)
 		tp_features.quirks = dmi_id->driver_data;
 
 	/* Device initialization */
-	tpacpi_pdev = platform_device_register_simple(TPACPI_DRVR_NAME, PLATFORM_DEVID_NONE,
-							NULL, 0);
+	tpacpi_pdev = platform_create_bundle(&tpacpi_pdriver, tpacpi_pdriver_probe,
+					     NULL, 0, NULL, 0);
 	if (IS_ERR(tpacpi_pdev)) {
 		ret = PTR_ERR(tpacpi_pdev);
 		tpacpi_pdev = NULL;
-		pr_err("unable to register platform device\n");
+		pr_err("unable to register platform device/driver bundle\n");
 		thinkpad_acpi_module_exit();
 		return ret;
 	}
+
 	tpacpi_sensors_pdev = platform_device_register_simple(
 						TPACPI_HWMON_DRVR_NAME,
 						PLATFORM_DEVID_NONE, NULL, 0);
@@ -11940,46 +11975,8 @@ static int __init thinkpad_acpi_module_init(void)
 		return ret;
 	}
 
-	mutex_init(&tpacpi_inputdev_send_mutex);
-	tpacpi_inputdev = input_allocate_device();
-	if (!tpacpi_inputdev) {
-		thinkpad_acpi_module_exit();
-		return -ENOMEM;
-	} else {
-		/* Prepare input device, but don't register */
-		tpacpi_inputdev->name = "ThinkPad Extra Buttons";
-		tpacpi_inputdev->phys = TPACPI_DRVR_NAME "/input0";
-		tpacpi_inputdev->id.bustype = BUS_HOST;
-		tpacpi_inputdev->id.vendor = thinkpad_id.vendor;
-		tpacpi_inputdev->id.product = TPACPI_HKEY_INPUT_PRODUCT;
-		tpacpi_inputdev->id.version = TPACPI_HKEY_INPUT_VERSION;
-		tpacpi_inputdev->dev.parent = &tpacpi_pdev->dev;
-	}
-
-	/* Init subdriver dependencies */
-	tpacpi_detect_brightness_capabilities();
-
-	/* Init subdrivers */
-	for (i = 0; i < ARRAY_SIZE(ibms_init); i++) {
-		ret = ibm_init(&ibms_init[i]);
-		if (ret >= 0 && *ibms_init[i].param)
-			ret = ibms_init[i].data->write(ibms_init[i].param);
-		if (ret < 0) {
-			thinkpad_acpi_module_exit();
-			return ret;
-		}
-	}
-
 	tpacpi_lifecycle = TPACPI_LIFE_RUNNING;
 
-	ret = platform_driver_register(&tpacpi_pdriver);
-	if (ret) {
-		pr_err("unable to register main platform driver\n");
-		thinkpad_acpi_module_exit();
-		return ret;
-	}
-	tp_features.platform_drv_registered = 1;
-
 	ret = platform_driver_register(&tpacpi_hwmon_pdriver);
 	if (ret) {
 		pr_err("unable to register hwmon platform driver\n");
@@ -11998,15 +11995,6 @@ static int __init thinkpad_acpi_module_init(void)
 		return ret;
 	}
 
-	ret = input_register_device(tpacpi_inputdev);
-	if (ret < 0) {
-		pr_err("unable to register input device\n");
-		thinkpad_acpi_module_exit();
-		return ret;
-	} else {
-		tp_features.input_device_registered = 1;
-	}
-
 	return 0;
 }