1 files changed, 134 insertions, 0 deletions
diff --git a/arch/arm/mach-u300/regulator.c b/arch/arm/mach-u300/regulator.c
new file mode 100644
index 000000000..c0cc1d82e
--- /dev/null
+++ b/arch/arm/mach-u300/regulator.c
@@ -0,0 +1,134 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * arch/arm/mach-u300/regulator.c
+ *
+ * Copyright (C) 2009 ST-Ericsson AB
+ * Handle board-bound regulators and board power not related
+ * to any devices.
+ * Author: Linus Walleij <linus.walleij@stericsson.com>
+ */
+#include <linux/device.h>
+#include <linux/signal.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/machine.h>
+#include <linux/regulator/consumer.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+
+/* Power Management Control 16bit (R/W) */
+#define U300_SYSCON_PMCR					(0x50)
+#define U300_SYSCON_PMCR_DCON_ENABLE				(0x0002)
+#define U300_SYSCON_PMCR_PWR_MGNT_ENABLE			(0x0001)
+
+/*
+ * Regulators that power the board and chip and which are
+ * not copuled to specific drivers are hogged in these
+ * instances.
+ */
+static struct regulator *main_power_15;
+
+/*
+ * This function is used from pm.h to shut down the system by
+ * resetting all regulators in turn and then disable regulator
+ * LDO D (main power).
+ */
+void u300_pm_poweroff(void)
+{
+	sigset_t old, all;
+
+	sigfillset(&all);
+	if (!sigprocmask(SIG_BLOCK, &all, &old)) {
+		/* Disable LDO D to shut down the system */
+		if (main_power_15)
+			regulator_disable(main_power_15);
+		else
+			pr_err("regulator not available to shut down system\n");
+		(void) sigprocmask(SIG_SETMASK, &old, NULL);
+	}
+	return;
+}
+
+/*
+ * Hog the regulators needed to power up the board.
+ */
+static int __init __u300_init_boardpower(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct device_node *syscon_np;
+	struct regmap *regmap;
+	int err;
+
+	pr_info("U300: setting up board power\n");
+
+	syscon_np = of_parse_phandle(np, "syscon", 0);
+	if (!syscon_np) {
+		pr_crit("U300: no syscon node\n");
+		return -ENODEV;
+	}
+	regmap = syscon_node_to_regmap(syscon_np);
+	if (IS_ERR(regmap)) {
+		pr_crit("U300: could not locate syscon regmap\n");
+		return PTR_ERR(regmap);
+	}
+
+	main_power_15 = regulator_get(&pdev->dev, "vana15");
+
+	if (IS_ERR(main_power_15)) {
+		pr_err("could not get vana15");
+		return PTR_ERR(main_power_15);
+	}
+	err = regulator_enable(main_power_15);
+	if (err) {
+		pr_err("could not enable vana15\n");
+		return err;
+	}
+
+	/*
+	 * On U300 a special system controller register pulls up the DC
+	 * until the vana15 (LDO D) regulator comes up. At this point, all
+	 * regulators are set and we do not need power control via
+	 * DC ON anymore. This function will likely be moved whenever
+	 * the rest of the U300 power management is implemented.
+	 */
+	pr_info("U300: disable system controller pull-up\n");
+	regmap_update_bits(regmap, U300_SYSCON_PMCR,
+			   U300_SYSCON_PMCR_DCON_ENABLE, 0);
+
+	/* Register globally exported PM poweroff hook */
+	pm_power_off = u300_pm_poweroff;
+
+	return 0;
+}
+
+static int __init s365_board_probe(struct platform_device *pdev)
+{
+	return __u300_init_boardpower(pdev);
+}
+
+static const struct of_device_id s365_board_match[] = {
+	{ .compatible = "stericsson,s365" },
+	{},
+};
+
+static struct platform_driver s365_board_driver = {
+	.driver		= {
+		.name   = "s365-board",
+		.of_match_table = s365_board_match,
+	},
+};
+
+/*
+ * So at module init time we hog the regulator!
+ */
+static int __init u300_init_boardpower(void)
+{
+	return platform_driver_probe(&s365_board_driver,
+				     s365_board_probe);
+}
+
+device_initcall(u300_init_boardpower);
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Linus Walleij");