ARM: ux500: Convert power-domain code into a regular platform driver

To make the code more standalone and moveable, let's convert it into a
platform driver.

Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

arch/arm/mach-ux500/cpu-db8500.c

@@ -26,8 +26,6 @@
 #include <asm/mach/map.h>
 #include <asm/mach/arch.h>
 
-#include "pm_domains.h"
-
 static int __init ux500_l2x0_unlock(void)
 {
 	int i;
@@ -115,9 +113,6 @@ static const struct of_device_id u8500_local_bus_nodes[] = {
 
 static void __init u8500_init_machine(void)
 {
-	/* Initialize ux500 power domains */
-	ux500_pm_domains_init();
-
 	of_platform_populate(NULL, u8500_local_bus_nodes,
 			     NULL, NULL);
 }

arch/arm/mach-ux500/pm_domains.c

@@ -6,6 +6,9 @@
  *
  * Implements PM domains using the generic PM domain for ux500.
  */
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
 #include <linux/printk.h>
 #include <linux/slab.h>
 #include <linux/err.h>
@@ -13,7 +16,6 @@
 #include <linux/pm_domain.h>
 
 #include <dt-bindings/arm/ux500_pm_domains.h>
-#include "pm_domains.h"
 
 static int pd_power_off(struct generic_pm_domain *domain)
 {
@@ -49,18 +51,17 @@ static struct generic_pm_domain *ux500_pm_domains[NR_DOMAINS] = {
 	[DOMAIN_VAPE] = &ux500_pm_domain_vape,
 };
 
-static const struct of_device_id ux500_pm_domain_matches[] __initconst = {
+static const struct of_device_id ux500_pm_domain_matches[] = {
 	{ .compatible = "stericsson,ux500-pm-domains", },
 	{ },
 };
 
-int __init ux500_pm_domains_init(void)
+static int ux500_pm_domains_probe(struct platform_device *pdev)
 {
-	struct device_node *np;
+	struct device_node *np = pdev->dev.of_node;
 	struct genpd_onecell_data *genpd_data;
 	int i;
 
-	np = of_find_matching_node(NULL, ux500_pm_domain_matches);
 	if (!np)
 		return -ENODEV;
 
@@ -77,3 +78,17 @@ int __init ux500_pm_domains_init(void)
 	of_genpd_add_provider_onecell(np, genpd_data);
 	return 0;
 }
+
+static struct platform_driver ux500_pm_domains_driver = {
+	.probe  = ux500_pm_domains_probe,
+	.driver = {
+		.name = "ux500_pm_domains",
+		.of_match_table = ux500_pm_domain_matches,
+	},
+};
+
+static int __init ux500_pm_domains_init(void)
+{
+	return platform_driver_register(&ux500_pm_domains_driver);
+}
+arch_initcall(ux500_pm_domains_init);

arch/arm/mach-ux500/pm_domains.h

-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * Copyright (C) 2014 Linaro Ltd.
- *
- * Author: Ulf Hansson <ulf.hansson@linaro.org>
- */
-
-#ifndef __MACH_UX500_PM_DOMAINS_H
-#define __MACH_UX500_PM_DOMAINS_H
-
-#ifdef CONFIG_PM_GENERIC_DOMAINS
-extern int __init ux500_pm_domains_init(void);
-#else
-static inline int ux500_pm_domains_init(void) { return 0; }
-#endif
-
-#endif