Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / power / reset / vexpress-poweroff.c

diff --git a/kernel/drivers/power/reset/vexpress-poweroff.c b/kernel/drivers/power/reset/vexpress-poweroff.c
new file mode 100644 (file)
index 0000000..6a9bf70
--- /dev/null
+++ b/kernel/drivers/power/reset/vexpress-poweroff.c
@@ -0,0 +1,156 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * Copyright (C) 2012 ARM Limited
+ */
+
+#include <linux/delay.h>
+#include <linux/notifier.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/reboot.h>
+#include <linux/stat.h>
+#include <linux/vexpress.h>
+
+static void vexpress_reset_do(struct device *dev, const char *what)
+{
+       int err = -ENOENT;
+       struct regmap *reg = dev_get_drvdata(dev);
+
+       if (reg) {
+               err = regmap_write(reg, 0, 0);
+               if (!err)
+                       mdelay(1000);
+       }
+
+       dev_emerg(dev, "Unable to %s (%d)\n", what, err);
+}
+
+static struct device *vexpress_power_off_device;
+
+static void vexpress_power_off(void)
+{
+       vexpress_reset_do(vexpress_power_off_device, "power off");
+}
+
+static struct device *vexpress_restart_device;
+
+static int vexpress_restart(struct notifier_block *this, unsigned long mode,
+                            void *cmd)
+{
+       vexpress_reset_do(vexpress_restart_device, "restart");
+
+       return NOTIFY_DONE;
+}
+
+static struct notifier_block vexpress_restart_nb = {
+       .notifier_call = vexpress_restart,
+       .priority = 128,
+};
+
+static ssize_t vexpress_reset_active_show(struct device *dev,
+               struct device_attribute *attr, char *buf)
+{
+       return sprintf(buf, "%d\n", vexpress_restart_device == dev);
+}
+
+static ssize_t vexpress_reset_active_store(struct device *dev,
+               struct device_attribute *attr, const char *buf, size_t count)
+{
+       long value;
+       int err = kstrtol(buf, 0, &value);
+
+       if (!err && value)
+               vexpress_restart_device = dev;
+
+       return err ? err : count;
+}
+
+DEVICE_ATTR(active, S_IRUGO | S_IWUSR, vexpress_reset_active_show,
+               vexpress_reset_active_store);
+
+
+enum vexpress_reset_func { FUNC_RESET, FUNC_SHUTDOWN, FUNC_REBOOT };
+
+static const struct of_device_id vexpress_reset_of_match[] = {
+       {
+               .compatible = "arm,vexpress-reset",
+               .data = (void *)FUNC_RESET,
+       }, {
+               .compatible = "arm,vexpress-shutdown",
+               .data = (void *)FUNC_SHUTDOWN
+       }, {
+               .compatible = "arm,vexpress-reboot",
+               .data = (void *)FUNC_REBOOT
+       },
+       {}
+};
+
+static int _vexpress_register_restart_handler(struct device *dev)
+{
+       int err;
+
+       vexpress_restart_device = dev;
+       err = register_restart_handler(&vexpress_restart_nb);
+       if (err) {
+               dev_err(dev, "cannot register restart handler (err=%d)\n", err);
+               return err;
+       }
+       device_create_file(dev, &dev_attr_active);
+
+       return 0;
+}
+
+static int vexpress_reset_probe(struct platform_device *pdev)
+{
+       const struct of_device_id *match =
+                       of_match_device(vexpress_reset_of_match, &pdev->dev);
+       struct regmap *regmap;
+       int ret = 0;
+
+       if (!match)
+               return -EINVAL;
+
+       regmap = devm_regmap_init_vexpress_config(&pdev->dev);
+       if (IS_ERR(regmap))
+               return PTR_ERR(regmap);
+       dev_set_drvdata(&pdev->dev, regmap);
+
+       switch ((enum vexpress_reset_func)match->data) {
+       case FUNC_SHUTDOWN:
+               vexpress_power_off_device = &pdev->dev;
+               pm_power_off = vexpress_power_off;
+               break;
+       case FUNC_RESET:
+               if (!vexpress_restart_device)
+                       ret = _vexpress_register_restart_handler(&pdev->dev);
+               break;
+       case FUNC_REBOOT:
+               ret = _vexpress_register_restart_handler(&pdev->dev);
+               break;
+       };
+
+       return ret;
+}
+
+static struct platform_driver vexpress_reset_driver = {
+       .probe = vexpress_reset_probe,
+       .driver = {
+               .name = "vexpress-reset",
+               .of_match_table = vexpress_reset_of_match,
+       },
+};
+
+static int __init vexpress_reset_init(void)
+{
+       return platform_driver_register(&vexpress_reset_driver);
+}
+device_initcall(vexpress_reset_init);