arm: vexpress: Move the poweroff/restart code to drivers/power/reset

This patch moves the arch/arm/mach-vexpress/reset.c functionality to
drivers/platform/reset/ and adds the necessary Kconfig wiring.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Pawel Moll <pawel.moll@arm.com>

3 files changed, 150 insertions, 1 deletions

diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index 1ae65b822864..349e9ae8090a 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -30,3 +30,10 @@ config POWER_RESET_RESTART
           Some boards don't actually have the ability to power off.
           Instead they restart, and u-boot holds the SoC until the
           user presses a key. u-boot then boots into Linux.
+
+config POWER_RESET_VEXPRESS
+        bool
+        depends on POWER_RESET
+        help
+          Power off and reset support for the ARM Ltd. Versatile
+          Express boards.
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index 0f317f50c56f..372807fd83f7 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -1,3 +1,4 @@
 obj-$(CONFIG_POWER_RESET_GPIO) += gpio-poweroff.o
 obj-$(CONFIG_POWER_RESET_QNAP) += qnap-poweroff.o
-obj-$(CONFIG_POWER_RESET_RESTART) += restart-poweroff.o
\ No newline at end of file
+obj-$(CONFIG_POWER_RESET_RESTART) += restart-poweroff.o
+obj-$(CONFIG_POWER_RESET_VEXPRESS) += vexpress-poweroff.o
diff --git a/drivers/power/reset/vexpress-poweroff.c b/drivers/power/reset/vexpress-poweroff.c
new file mode 100644
index 000000000000..465923aa3819
--- /dev/null
+++ b/drivers/power/reset/vexpress-poweroff.c
@@ -0,0 +1,141 @@
+/*
+ * 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/jiffies.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/stat.h>
+#include <linux/vexpress.h>
+
+static void vexpress_reset_do(struct device *dev, const char *what)
+{
+        int err = -ENOENT;
+        struct vexpress_config_func *func =
+                        vexpress_config_func_get_by_dev(dev);
+
+        if (func) {
+                unsigned long timeout;
+
+                err = vexpress_config_write(func, 0, 0);
+
+                timeout = jiffies + HZ;
+                while (time_before(jiffies, timeout))
+                        cpu_relax();
+        }
+
+        dev_emerg(dev, "Unable to %s (%d)\n", what, err);
+}
+
+static struct device *vexpress_power_off_device;
+
+void vexpress_power_off(void)
+{
+        vexpress_reset_do(vexpress_power_off_device, "power off");
+}
+
+static struct device *vexpress_restart_device;
+
+void vexpress_restart(char str, const char *cmd)
+{
+        vexpress_reset_do(vexpress_restart_device, "restart");
+}
+
+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 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_reset_probe(struct platform_device *pdev)
+{
+        enum vexpress_reset_func func;
+        const struct of_device_id *match =
+                        of_match_device(vexpress_reset_of_match, &pdev->dev);
+
+        if (match)
+                func = (enum vexpress_reset_func)match->data;
+        else
+                func = pdev->id_entry->driver_data;
+
+        switch (func) {
+        case FUNC_SHUTDOWN:
+                vexpress_power_off_device = &pdev->dev;
+                break;
+        case FUNC_RESET:
+                if (!vexpress_restart_device)
+                        vexpress_restart_device = &pdev->dev;
+                device_create_file(&pdev->dev, &dev_attr_active);
+                break;
+        case FUNC_REBOOT:
+                vexpress_restart_device = &pdev->dev;
+                device_create_file(&pdev->dev, &dev_attr_active);
+                break;
+        };
+
+        return 0;
+}
+
+static const struct platform_device_id vexpress_reset_id_table[] = {
+        { .name = "vexpress-reset", .driver_data = FUNC_RESET, },
+        { .name = "vexpress-shutdown", .driver_data = FUNC_SHUTDOWN, },
+        { .name = "vexpress-reboot", .driver_data = FUNC_REBOOT, },
+        {}
+};
+
+static struct platform_driver vexpress_reset_driver = {
+        .probe = vexpress_reset_probe,
+        .driver = {
+                .name = "vexpress-reset",
+                .of_match_table = vexpress_reset_of_match,
+        },
+        .id_table = vexpress_reset_id_table,
+};
+
+static int __init vexpress_reset_init(void)
+{
+        return platform_driver_register(&vexpress_reset_driver);
+}
+device_initcall(vexpress_reset_init);