diff options
Diffstat (limited to '')
-rw-r--r-- | arch/powerpc/sysdev/fsl_mpic_timer_wakeup.c | 155 |
1 files changed, 155 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 000000000..c2baa283e --- /dev/null +++ b/arch/powerpc/sysdev/fsl_mpic_timer_wakeup.c @@ -0,0 +1,155 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * MPIC timer wakeup driver + * + * Copyright 2013 Freescale Semiconductor, Inc. + */ + +#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) +{ + time64_t interval = 0; + + mutex_lock(&sysfs_lock); + if (fsl_wakeup->timer) { + mpic_get_remain_time(fsl_wakeup->timer, &interval); + interval++; + } + mutex_unlock(&sysfs_lock); + + return sprintf(buf, "%lld\n", interval); +} + +static ssize_t fsl_timer_wakeup_store(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t count) +{ + time64_t interval; + int ret; + + if (kstrtoll(buf, 0, &interval)) + 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) { + 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>"); |