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authorDongsheng.wang@freescale.com <Dongsheng.wang@freescale.com>2013-04-09 06:22:32 +0400
committerScott Wood <scottwood@freescale.com>2013-07-02 03:38:42 +0400
commita63b3bc7db32b63bfe5f48fa8582f931db81c86e (patch)
tree7e119f7c7129a103d5a4d70390888cbbf0e2824c /arch/powerpc/sysdev/fsl_mpic_timer_wakeup.c
parent9e6f31a9dbc58f6a5661f8dc8c919441b8d3ced4 (diff)
downloadlinux-a63b3bc7db32b63bfe5f48fa8582f931db81c86e.tar.xz
powerpc/fsl: add MPIC timer wakeup support
The driver provides a way to wake up the system by the MPIC timer. For example, echo 5 > /sys/devices/system/mpic/timer_wakeup echo standby > /sys/power/state After 5 seconds the MPIC timer will generate an interrupt to wake up the system. Signed-off-by: Wang Dongsheng <dongsheng.wang@freescale.com> Signed-off-by: Zhao Chenhui <chenhui.zhao@freescale.com> Signed-off-by: Li Yang <leoli@freescale.com>
Diffstat (limited to 'arch/powerpc/sysdev/fsl_mpic_timer_wakeup.c')
-rw-r--r--arch/powerpc/sysdev/fsl_mpic_timer_wakeup.c161
1 files changed, 161 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/fsl_mpic_timer_wakeup.c b/arch/powerpc/sysdev/fsl_mpic_timer_wakeup.c
new file mode 100644
index 000000000000..1707bf04dec6
--- /dev/null
+++ b/arch/powerpc/sysdev/fsl_mpic_timer_wakeup.c
@@ -0,0 +1,161 @@
+/*
+ * MPIC timer wakeup driver
+ *
+ * Copyright 2013 Freescale Semiconductor, Inc.
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/device.h>
+
+#include <asm/mpic_timer.h>
+#include <asm/mpic.h>
+
+struct fsl_mpic_timer_wakeup {
+ struct mpic_timer *timer;
+ struct work_struct free_work;
+};
+
+static struct fsl_mpic_timer_wakeup *fsl_wakeup;
+static DEFINE_MUTEX(sysfs_lock);
+
+static void fsl_free_resource(struct work_struct *ws)
+{
+ struct fsl_mpic_timer_wakeup *wakeup =
+ container_of(ws, struct fsl_mpic_timer_wakeup, free_work);
+
+ mutex_lock(&sysfs_lock);
+
+ if (wakeup->timer) {
+ disable_irq_wake(wakeup->timer->irq);
+ mpic_free_timer(wakeup->timer);
+ }
+
+ wakeup->timer = NULL;
+ mutex_unlock(&sysfs_lock);
+}
+
+static irqreturn_t fsl_mpic_timer_irq(int irq, void *dev_id)
+{
+ struct fsl_mpic_timer_wakeup *wakeup = dev_id;
+
+ schedule_work(&wakeup->free_work);
+
+ return wakeup->timer ? IRQ_HANDLED : IRQ_NONE;
+}
+
+static ssize_t fsl_timer_wakeup_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct timeval interval;
+ int val = 0;
+
+ mutex_lock(&sysfs_lock);
+ if (fsl_wakeup->timer) {
+ mpic_get_remain_time(fsl_wakeup->timer, &interval);
+ val = interval.tv_sec + 1;
+ }
+ mutex_unlock(&sysfs_lock);
+
+ return sprintf(buf, "%d\n", val);
+}
+
+static ssize_t fsl_timer_wakeup_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t count)
+{
+ struct timeval interval;
+ int ret;
+
+ interval.tv_usec = 0;
+ if (kstrtol(buf, 0, &interval.tv_sec))
+ return -EINVAL;
+
+ mutex_lock(&sysfs_lock);
+
+ if (fsl_wakeup->timer) {
+ disable_irq_wake(fsl_wakeup->timer->irq);
+ mpic_free_timer(fsl_wakeup->timer);
+ fsl_wakeup->timer = NULL;
+ }
+
+ if (!interval.tv_sec) {
+ mutex_unlock(&sysfs_lock);
+ return count;
+ }
+
+ fsl_wakeup->timer = mpic_request_timer(fsl_mpic_timer_irq,
+ fsl_wakeup, &interval);
+ if (!fsl_wakeup->timer) {
+ mutex_unlock(&sysfs_lock);
+ return -EINVAL;
+ }
+
+ ret = enable_irq_wake(fsl_wakeup->timer->irq);
+ if (ret) {
+ mpic_free_timer(fsl_wakeup->timer);
+ fsl_wakeup->timer = NULL;
+ mutex_unlock(&sysfs_lock);
+
+ return ret;
+ }
+
+ mpic_start_timer(fsl_wakeup->timer);
+
+ mutex_unlock(&sysfs_lock);
+
+ return count;
+}
+
+static struct device_attribute mpic_attributes = __ATTR(timer_wakeup, 0644,
+ fsl_timer_wakeup_show, fsl_timer_wakeup_store);
+
+static int __init fsl_wakeup_sys_init(void)
+{
+ int ret;
+
+ fsl_wakeup = kzalloc(sizeof(struct fsl_mpic_timer_wakeup), GFP_KERNEL);
+ if (!fsl_wakeup)
+ return -ENOMEM;
+
+ INIT_WORK(&fsl_wakeup->free_work, fsl_free_resource);
+
+ ret = device_create_file(mpic_subsys.dev_root, &mpic_attributes);
+ if (ret)
+ kfree(fsl_wakeup);
+
+ return ret;
+}
+
+static void __exit fsl_wakeup_sys_exit(void)
+{
+ device_remove_file(mpic_subsys.dev_root, &mpic_attributes);
+
+ mutex_lock(&sysfs_lock);
+
+ if (fsl_wakeup->timer) {
+ disable_irq_wake(fsl_wakeup->timer->irq);
+ mpic_free_timer(fsl_wakeup->timer);
+ }
+
+ kfree(fsl_wakeup);
+
+ mutex_unlock(&sysfs_lock);
+}
+
+module_init(fsl_wakeup_sys_init);
+module_exit(fsl_wakeup_sys_exit);
+
+MODULE_DESCRIPTION("Freescale MPIC global timer wakeup driver");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Wang Dongsheng <dongsheng.wang@freescale.com>");