1 files changed, 112 insertions, 0 deletions
diff --git a/drivers/power/reset/st-poweroff.c b/drivers/power/reset/st-poweroff.c
new file mode 100644
index 000000000..5ccaacffa
--- /dev/null
+++ b/drivers/power/reset/st-poweroff.c
@@ -0,0 +1,112 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2014 STMicroelectronics
+ *
+ * Power off Restart driver, used in STMicroelectronics devices.
+ *
+ * Author: Christophe Kerello <christophe.kerello@st.com>
+ */
+
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/syscon.h>
+#include <linux/reboot.h>
+#include <linux/regmap.h>
+
+struct reset_syscfg {
+	struct regmap *regmap;
+	/* syscfg used for reset */
+	unsigned int offset_rst;
+	unsigned int mask_rst;
+	/* syscfg used for unmask the reset */
+	unsigned int offset_rst_msk;
+	unsigned int mask_rst_msk;
+};
+
+/* STiH407 */
+#define STIH407_SYSCFG_4000	0x0
+#define STIH407_SYSCFG_4008	0x20
+
+static struct reset_syscfg stih407_reset = {
+	.offset_rst = STIH407_SYSCFG_4000,
+	.mask_rst = BIT(0),
+	.offset_rst_msk = STIH407_SYSCFG_4008,
+	.mask_rst_msk = BIT(0)
+};
+
+
+static struct reset_syscfg *st_restart_syscfg;
+
+static int st_restart(struct notifier_block *this, unsigned long mode,
+		      void *cmd)
+{
+	/* reset syscfg updated */
+	regmap_update_bits(st_restart_syscfg->regmap,
+			   st_restart_syscfg->offset_rst,
+			   st_restart_syscfg->mask_rst,
+			   0);
+
+	/* unmask the reset */
+	regmap_update_bits(st_restart_syscfg->regmap,
+			   st_restart_syscfg->offset_rst_msk,
+			   st_restart_syscfg->mask_rst_msk,
+			   0);
+
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block st_restart_nb = {
+	.notifier_call = st_restart,
+	.priority = 192,
+};
+
+static const struct of_device_id st_reset_of_match[] = {
+	{
+		.compatible = "st,stih407-restart",
+		.data = (void *)&stih407_reset,
+	},
+	{}
+};
+
+static int st_reset_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	const struct of_device_id *match;
+	struct device *dev = &pdev->dev;
+
+	match = of_match_device(st_reset_of_match, dev);
+	if (!match)
+		return -ENODEV;
+
+	st_restart_syscfg = (struct reset_syscfg *)match->data;
+
+	st_restart_syscfg->regmap =
+		syscon_regmap_lookup_by_phandle(np, "st,syscfg");
+	if (IS_ERR(st_restart_syscfg->regmap)) {
+		dev_err(dev, "No syscfg phandle specified\n");
+		return PTR_ERR(st_restart_syscfg->regmap);
+	}
+
+	return register_restart_handler(&st_restart_nb);
+}
+
+static struct platform_driver st_reset_driver = {
+	.probe = st_reset_probe,
+	.driver = {
+		.name = "st_reset",
+		.of_match_table = st_reset_of_match,
+	},
+};
+
+static int __init st_reset_init(void)
+{
+	return platform_driver_register(&st_reset_driver);
+}
+
+device_initcall(st_reset_init);
+
+MODULE_AUTHOR("Christophe Kerello <christophe.kerello@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics Power off Restart driver");
+MODULE_LICENSE("GPL v2");