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path: root/drivers/power/reset/st-poweroff.c
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Diffstat (limited to 'drivers/power/reset/st-poweroff.c')
-rw-r--r--drivers/power/reset/st-poweroff.c112
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 0000000000..56ba218738
--- /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_device.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");