[PATCHv3 1/2] power: reset: Add generic SYSCON register mapped poweroff.

From: Moritz Fischer
Date: Wed Mar 11 2015 - 20:37:47 EST


Add a generic SYSCON register mapped poweroff mechanism.

Signed-off-by: Moritz Fischer <moritz.fischer@xxxxxxxxx>
---
drivers/power/reset/Kconfig | 7 +++
drivers/power/reset/Makefile | 1 +
drivers/power/reset/syscon-poweroff.c | 102 ++++++++++++++++++++++++++++++++++
3 files changed, 110 insertions(+)

diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index 27f6646..4bae079 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -151,6 +151,13 @@ config POWER_RESET_SYSCON
help
Reboot support for generic SYSCON mapped register reset.

+config POWER_RESET_SYSCON_POWEROFF
+ bool "Generic SYSCON regmap poweroff driver"
+ depends on OF
+ select MFD_SYSCON
+ help
+ Poweroff support for generic SYSCON mapped register poweroff.
+
config POWER_RESET_RMOBILE
tristate "Renesas R-Mobile reset driver"
depends on ARCH_RMOBILE || COMPILE_TEST
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index 11de15b..dbe06c3 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -17,4 +17,5 @@ obj-$(CONFIG_POWER_RESET_VEXPRESS) += vexpress-poweroff.o
obj-$(CONFIG_POWER_RESET_XGENE) += xgene-reboot.o
obj-$(CONFIG_POWER_RESET_KEYSTONE) += keystone-reset.o
obj-$(CONFIG_POWER_RESET_SYSCON) += syscon-reboot.o
+obj-$(CONFIG_POWER_RESET_SYSCON_POWEROFF) += syscon-poweroff.o
obj-$(CONFIG_POWER_RESET_RMOBILE) += rmobile-reset.o
diff --git a/drivers/power/reset/syscon-poweroff.c b/drivers/power/reset/syscon-poweroff.c
new file mode 100644
index 0000000..5560b0d
--- /dev/null
+++ b/drivers/power/reset/syscon-poweroff.c
@@ -0,0 +1,102 @@
+/*
+ * Generic Syscon Poweroff Driver
+ *
+ * Copyright (c) 2015, National Instruments Corp.
+ * Author: Moritz Fischer <moritz.fischer@xxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kallsyms.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/notifier.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
+#include <linux/regmap.h>
+
+static struct regmap *map;
+static u32 offset;
+static u32 mask;
+
+void syscon_poweroff(void)
+{
+ /* Issue the poweroff */
+ regmap_write(map, offset, mask);
+
+ mdelay(1000);
+
+ pr_emerg("Unable to poweroff system\n");
+}
+
+static int syscon_poweroff_probe(struct platform_device *pdev)
+{
+ char symname[KSYM_NAME_LEN];
+
+ map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "regmap");
+ if (IS_ERR(map)) {
+ dev_err(&pdev->dev, "unable to get syscon");
+ return PTR_ERR(map);
+ }
+
+ if (of_property_read_u32(pdev->dev.of_node, "offset", &offset)) {
+ dev_err(&pdev->dev, "unable to read 'offset'");
+ return -EINVAL;
+ }
+
+ if (of_property_read_u32(pdev->dev.of_node, "mask", &mask)) {
+ dev_err(&pdev->dev, "unable to read 'mask'");
+ return -EINVAL;
+ }
+
+ if (pm_power_off) {
+ lookup_symbol_name((ulong)pm_power_off, symname);
+ dev_err(&pdev->dev,
+ "pm_power_off already claimed %p %s",
+ pm_power_off, symname);
+ return -EBUSY;
+ }
+
+ pm_power_off = syscon_poweroff;
+
+ return 0;
+}
+
+static int syscon_poweroff_remove(struct platform_device *pdev)
+{
+ if (pm_power_off == syscon_poweroff)
+ pm_power_off = NULL;
+
+ return 0;
+}
+
+static const struct of_device_id syscon_poweroff_of_match[] = {
+ { .compatible = "syscon-poweroff" },
+ {}
+};
+
+static struct platform_driver syscon_poweroff_driver = {
+ .probe = syscon_poweroff_probe,
+ .remove = syscon_poweroff_remove,
+ .driver = {
+ .name = "syscon-poweroff",
+ .of_match_table = syscon_poweroff_of_match,
+ },
+};
+
+static int __init syscon_poweroff_register(void)
+{
+ return platform_driver_register(&syscon_poweroff_driver);
+}
+device_initcall(syscon_poweroff_register);
--
1.9.3

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