swh:1:snp:c3bf2749e3476071fa748f67b0ffa2fdc5fe49d9
Tip revision: 8834f5600cf3c8db365e18a3d5cac2c2780c81e5 authored by Linus Torvalds on 03 February 2019, 21:48:04 UTC
Linux 5.0-rc5
Linux 5.0-rc5
Tip revision: 8834f56
remoteproc_sysfs.c
/*
* Remote Processor Framework
*
* 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.
*/
#include <linux/remoteproc.h>
#include "remoteproc_internal.h"
#define to_rproc(d) container_of(d, struct rproc, dev)
/* Expose the loaded / running firmware name via sysfs */
static ssize_t firmware_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct rproc *rproc = to_rproc(dev);
return sprintf(buf, "%s\n", rproc->firmware);
}
/* Change firmware name via sysfs */
static ssize_t firmware_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct rproc *rproc = to_rproc(dev);
char *p;
int err, len = count;
err = mutex_lock_interruptible(&rproc->lock);
if (err) {
dev_err(dev, "can't lock rproc %s: %d\n", rproc->name, err);
return -EINVAL;
}
if (rproc->state != RPROC_OFFLINE) {
dev_err(dev, "can't change firmware while running\n");
err = -EBUSY;
goto out;
}
len = strcspn(buf, "\n");
if (!len) {
dev_err(dev, "can't provide a NULL firmware\n");
err = -EINVAL;
goto out;
}
p = kstrndup(buf, len, GFP_KERNEL);
if (!p) {
err = -ENOMEM;
goto out;
}
kfree(rproc->firmware);
rproc->firmware = p;
out:
mutex_unlock(&rproc->lock);
return err ? err : count;
}
static DEVICE_ATTR_RW(firmware);
/*
* A state-to-string lookup table, for exposing a human readable state
* via sysfs. Always keep in sync with enum rproc_state
*/
static const char * const rproc_state_string[] = {
[RPROC_OFFLINE] = "offline",
[RPROC_SUSPENDED] = "suspended",
[RPROC_RUNNING] = "running",
[RPROC_CRASHED] = "crashed",
[RPROC_DELETED] = "deleted",
[RPROC_LAST] = "invalid",
};
/* Expose the state of the remote processor via sysfs */
static ssize_t state_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct rproc *rproc = to_rproc(dev);
unsigned int state;
state = rproc->state > RPROC_LAST ? RPROC_LAST : rproc->state;
return sprintf(buf, "%s\n", rproc_state_string[state]);
}
/* Change remote processor state via sysfs */
static ssize_t state_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct rproc *rproc = to_rproc(dev);
int ret = 0;
if (sysfs_streq(buf, "start")) {
if (rproc->state == RPROC_RUNNING)
return -EBUSY;
ret = rproc_boot(rproc);
if (ret)
dev_err(&rproc->dev, "Boot failed: %d\n", ret);
} else if (sysfs_streq(buf, "stop")) {
if (rproc->state != RPROC_RUNNING)
return -EINVAL;
rproc_shutdown(rproc);
} else {
dev_err(&rproc->dev, "Unrecognised option: %s\n", buf);
ret = -EINVAL;
}
return ret ? ret : count;
}
static DEVICE_ATTR_RW(state);
static struct attribute *rproc_attrs[] = {
&dev_attr_firmware.attr,
&dev_attr_state.attr,
NULL
};
static const struct attribute_group rproc_devgroup = {
.attrs = rproc_attrs
};
static const struct attribute_group *rproc_devgroups[] = {
&rproc_devgroup,
NULL
};
struct class rproc_class = {
.name = "remoteproc",
.dev_groups = rproc_devgroups,
};
int __init rproc_init_sysfs(void)
{
/* create remoteproc device class for sysfs */
int err = class_register(&rproc_class);
if (err)
pr_err("remoteproc: unable to register class\n");
return err;
}
void __exit rproc_exit_sysfs(void)
{
class_unregister(&rproc_class);
}