930eec0be2
The rproc_char_device_remove() call currently unmaps the cdev region instead of simply deleting the cdev that was added as a part of the rproc_char_device_add() call. This change fixes that behaviour, and also fixes the order in which device_del() and cdev_del() need to be called. Signed-off-by: Siddharth Gupta <sidgup@codeaurora.org> Link: https://lore.kernel.org/r/1623723671-5517-4-git-send-email-sidgup@codeaurora.org Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
138 lines
3.2 KiB
C
138 lines
3.2 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* Character device interface driver for Remoteproc framework.
|
|
*
|
|
* Copyright (c) 2020, The Linux Foundation. All rights reserved.
|
|
*/
|
|
|
|
#include <linux/cdev.h>
|
|
#include <linux/compat.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/module.h>
|
|
#include <linux/remoteproc.h>
|
|
#include <linux/uaccess.h>
|
|
#include <uapi/linux/remoteproc_cdev.h>
|
|
|
|
#include "remoteproc_internal.h"
|
|
|
|
#define NUM_RPROC_DEVICES 64
|
|
static dev_t rproc_major;
|
|
|
|
static ssize_t rproc_cdev_write(struct file *filp, const char __user *buf, size_t len, loff_t *pos)
|
|
{
|
|
struct rproc *rproc = container_of(filp->f_inode->i_cdev, struct rproc, cdev);
|
|
int ret = 0;
|
|
char cmd[10];
|
|
|
|
if (!len || len > sizeof(cmd))
|
|
return -EINVAL;
|
|
|
|
ret = copy_from_user(cmd, buf, len);
|
|
if (ret)
|
|
return -EFAULT;
|
|
|
|
if (!strncmp(cmd, "start", len)) {
|
|
if (rproc->state == RPROC_RUNNING ||
|
|
rproc->state == RPROC_ATTACHED)
|
|
return -EBUSY;
|
|
|
|
ret = rproc_boot(rproc);
|
|
} else if (!strncmp(cmd, "stop", len)) {
|
|
if (rproc->state != RPROC_RUNNING &&
|
|
rproc->state != RPROC_ATTACHED)
|
|
return -EINVAL;
|
|
|
|
rproc_shutdown(rproc);
|
|
} else if (!strncmp(cmd, "detach", len)) {
|
|
if (rproc->state != RPROC_ATTACHED)
|
|
return -EINVAL;
|
|
|
|
ret = rproc_detach(rproc);
|
|
} else {
|
|
dev_err(&rproc->dev, "Unrecognized option\n");
|
|
ret = -EINVAL;
|
|
}
|
|
|
|
return ret ? ret : len;
|
|
}
|
|
|
|
static long rproc_device_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
|
|
{
|
|
struct rproc *rproc = container_of(filp->f_inode->i_cdev, struct rproc, cdev);
|
|
void __user *argp = (void __user *)arg;
|
|
s32 param;
|
|
|
|
switch (ioctl) {
|
|
case RPROC_SET_SHUTDOWN_ON_RELEASE:
|
|
if (copy_from_user(¶m, argp, sizeof(s32)))
|
|
return -EFAULT;
|
|
|
|
rproc->cdev_put_on_release = !!param;
|
|
break;
|
|
case RPROC_GET_SHUTDOWN_ON_RELEASE:
|
|
param = (s32)rproc->cdev_put_on_release;
|
|
if (copy_to_user(argp, ¶m, sizeof(s32)))
|
|
return -EFAULT;
|
|
|
|
break;
|
|
default:
|
|
dev_err(&rproc->dev, "Unsupported ioctl\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int rproc_cdev_release(struct inode *inode, struct file *filp)
|
|
{
|
|
struct rproc *rproc = container_of(inode->i_cdev, struct rproc, cdev);
|
|
int ret = 0;
|
|
|
|
if (!rproc->cdev_put_on_release)
|
|
return 0;
|
|
|
|
if (rproc->state == RPROC_RUNNING)
|
|
rproc_shutdown(rproc);
|
|
else if (rproc->state == RPROC_ATTACHED)
|
|
ret = rproc_detach(rproc);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static const struct file_operations rproc_fops = {
|
|
.write = rproc_cdev_write,
|
|
.unlocked_ioctl = rproc_device_ioctl,
|
|
.compat_ioctl = compat_ptr_ioctl,
|
|
.release = rproc_cdev_release,
|
|
};
|
|
|
|
int rproc_char_device_add(struct rproc *rproc)
|
|
{
|
|
int ret;
|
|
|
|
cdev_init(&rproc->cdev, &rproc_fops);
|
|
rproc->cdev.owner = THIS_MODULE;
|
|
|
|
rproc->dev.devt = MKDEV(MAJOR(rproc_major), rproc->index);
|
|
cdev_set_parent(&rproc->cdev, &rproc->dev.kobj);
|
|
ret = cdev_add(&rproc->cdev, rproc->dev.devt, 1);
|
|
if (ret < 0)
|
|
dev_err(&rproc->dev, "Failed to add char dev for %s\n", rproc->name);
|
|
|
|
return ret;
|
|
}
|
|
|
|
void rproc_char_device_remove(struct rproc *rproc)
|
|
{
|
|
cdev_del(&rproc->cdev);
|
|
}
|
|
|
|
void __init rproc_init_cdev(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = alloc_chrdev_region(&rproc_major, 0, NUM_RPROC_DEVICES, "remoteproc");
|
|
if (ret < 0)
|
|
pr_err("Failed to alloc rproc_cdev region, err %d\n", ret);
|
|
}
|