diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/rpmsg/Kconfig | 8 | ||||
| -rw-r--r-- | drivers/rpmsg/Makefile | 1 | ||||
| -rw-r--r-- | drivers/rpmsg/rpmsg_char.c | 585 | ||||
| -rw-r--r-- | drivers/rpmsg/rpmsg_internal.h | 15 |
4 files changed, 609 insertions, 0 deletions
diff --git a/drivers/rpmsg/Kconfig b/drivers/rpmsg/Kconfig index de31c5f14dd9..fa0d582efb3d 100644 --- a/drivers/rpmsg/Kconfig +++ b/drivers/rpmsg/Kconfig @@ -4,6 +4,14 @@ menu "Rpmsg drivers" config RPMSG tristate +config RPMSG_CHAR + tristate "RPMSG device interface" + depends on RPMSG + help + Say Y here to export rpmsg endpoints as device files, usually found + in /dev. They make it possible for user-space programs to send and + receive rpmsg packets. + config RPMSG_QCOM_SMD tristate "Qualcomm Shared Memory Driver (SMD)" depends on QCOM_SMEM diff --git a/drivers/rpmsg/Makefile b/drivers/rpmsg/Makefile index ae9c9132cf76..fae9a6d548fb 100644 --- a/drivers/rpmsg/Makefile +++ b/drivers/rpmsg/Makefile @@ -1,3 +1,4 @@ obj-$(CONFIG_RPMSG) += rpmsg_core.o +obj-$(CONFIG_RPMSG_CHAR) += rpmsg_char.o obj-$(CONFIG_RPMSG_QCOM_SMD) += qcom_smd.o obj-$(CONFIG_RPMSG_VIRTIO) += virtio_rpmsg_bus.o diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c new file mode 100644 index 000000000000..a78b6b79cea4 --- /dev/null +++ b/drivers/rpmsg/rpmsg_char.c @@ -0,0 +1,585 @@ +/* + * Copyright (c) 2016, Linaro Ltd. + * Copyright (c) 2012, Michal Simek <monstr@monstr.eu> + * Copyright (c) 2012, PetaLogix + * Copyright (c) 2011, Texas Instruments, Inc. + * Copyright (c) 2011, Google, Inc. + * + * Based on rpmsg performance statistics driver by Michal Simek, which in turn + * was based on TI & Google OMX rpmsg driver. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only 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/cdev.h> +#include <linux/device.h> +#include <linux/fs.h> +#include <linux/idr.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/poll.h> +#include <linux/rpmsg.h> +#include <linux/skbuff.h> +#include <linux/slab.h> +#include <linux/uaccess.h> +#include <uapi/linux/rpmsg.h> + +#include "rpmsg_internal.h" + +#define RPMSG_DEV_MAX (MINORMASK + 1) + +static dev_t rpmsg_major; +static struct class *rpmsg_class; + +static DEFINE_IDA(rpmsg_ctrl_ida); +static DEFINE_IDA(rpmsg_ept_ida); +static DEFINE_IDA(rpmsg_minor_ida); + +#define dev_to_eptdev(dev) container_of(dev, struct rpmsg_eptdev, dev) +#define cdev_to_eptdev(i_cdev) container_of(i_cdev, struct rpmsg_eptdev, cdev) + +#define dev_to_ctrldev(dev) container_of(dev, struct rpmsg_ctrldev, dev) +#define cdev_to_ctrldev(i_cdev) container_of(i_cdev, struct rpmsg_ctrldev, cdev) + +/** + * struct rpmsg_ctrldev - control device for instantiating endpoint devices + * @rpdev: underlaying rpmsg device + * @cdev: cdev for the ctrl device + * @dev: device for the ctrl device + */ +struct rpmsg_ctrldev { + struct rpmsg_device *rpdev; + struct cdev cdev; + struct device dev; +}; + +/** + * struct rpmsg_eptdev - endpoint device context + * @dev: endpoint device + * @cdev: cdev for the endpoint device + * @rpdev: underlaying rpmsg device + * @chinfo: info used to open the endpoint + * @ept_lock: synchronization of @ept modifications + * @ept: rpmsg endpoint reference, when open + * @queue_lock: synchronization of @queue operations + * @queue: incoming message queue + * @readq: wait object for incoming queue + */ +struct rpmsg_eptdev { + struct device dev; + struct cdev cdev; + + struct rpmsg_device *rpdev; + struct rpmsg_channel_info chinfo; + + struct mutex ept_lock; + struct rpmsg_endpoint *ept; + + spinlock_t queue_lock; + struct sk_buff_head queue; + wait_queue_head_t readq; +}; + +static int rpmsg_eptdev_destroy(struct device *dev, void *data) +{ + struct rpmsg_eptdev *eptdev = dev_to_eptdev(dev); + + mutex_lock(&eptdev->ept_lock); + if (eptdev->ept) { + rpmsg_destroy_ept(eptdev->ept); + eptdev->ept = NULL; + } + mutex_unlock(&eptdev->ept_lock); + + /* wake up any blocked readers */ + wake_up_interruptible(&eptdev->readq); + + device_del(&eptdev->dev); + put_device(&eptdev->dev); + + return 0; +} + +static int rpmsg_ept_cb(struct rpmsg_device *rpdev, void *buf, int len, + void *priv, u32 addr) +{ + struct rpmsg_eptdev *eptdev = priv; + struct sk_buff *skb; + + skb = alloc_skb(len, GFP_ATOMIC); + if (!skb) + return -ENOMEM; + + memcpy(skb_put(skb, len), buf, len); + + spin_lock(&eptdev->queue_lock); + skb_queue_tail(&eptdev->queue, skb); + spin_unlock(&eptdev->queue_lock); + + /* wake up any blocking processes, waiting for new data */ + wake_up_interruptible(&eptdev->readq); + + return 0; +} + +static int rpmsg_eptdev_open(struct inode *inode, struct file *filp) +{ + struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev); + struct rpmsg_endpoint *ept; + struct rpmsg_device *rpdev = eptdev->rpdev; + struct device *dev = &eptdev->dev; + + get_device(dev); + + ept = rpmsg_create_ept(rpdev, rpmsg_ept_cb, eptdev, eptdev->chinfo); + if (!ept) { + dev_err(dev, "failed to open %s\n", eptdev->chinfo.name); + put_device(dev); + return -EINVAL; + } + + eptdev->ept = ept; + filp->private_data = eptdev; + + return 0; +} + +static int rpmsg_eptdev_release(struct inode *inode, struct file *filp) +{ + struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev); + struct device *dev = &eptdev->dev; + struct sk_buff *skb; + + /* Close the endpoint, if it's not already destroyed by the parent */ + mutex_lock(&eptdev->ept_lock); + if (eptdev->ept) { + rpmsg_destroy_ept(eptdev->ept); + eptdev->ept = NULL; + } + mutex_unlock(&eptdev->ept_lock); + + /* Discard all SKBs */ + while (!skb_queue_empty(&eptdev->queue)) { + skb = skb_dequeue(&eptdev->queue); + kfree_skb(skb); + } + + put_device(dev); + + return 0; +} + +static ssize_t rpmsg_eptdev_read(struct file *filp, char __user *buf, + size_t len, loff_t *f_pos) +{ + struct rpmsg_eptdev *eptdev = filp->private_data; + unsigned long flags; + struct sk_buff *skb; + int use; + + if (!eptdev->ept) + return -EPIPE; + + spin_lock_irqsave(&eptdev->queue_lock, flags); + + /* Wait for data in the queue */ + if (skb_queue_empty(&eptdev->queue)) { + spin_unlock_irqrestore(&eptdev->queue_lock, flags); + + if (filp->f_flags & O_NONBLOCK) + return -EAGAIN; + + /* Wait until we get data or the endpoint goes away */ + if (wait_event_interruptible(eptdev->readq, + !skb_queue_empty(&eptdev->queue) || + !eptdev->ept)) + return -ERESTARTSYS; + + /* We lost the endpoint while waiting */ + if (!eptdev->ept) + return -EPIPE; + + spin_lock_irqsave(&eptdev->queue_lock, flags); + } + + skb = skb_dequeue(&eptdev->queue); + if (!skb) + return -EFAULT; + + spin_unlock_irqrestore(&eptdev->queue_lock, flags); + + use = min_t(size_t, len, skb->len); + if (copy_to_user(buf, skb->data, use)) + use = -EFAULT; + + kfree_skb(skb); + + return use; +} + +static ssize_t rpmsg_eptdev_write(struct file *filp, const char __user *buf, + size_t len, loff_t *f_pos) +{ + struct rpmsg_eptdev *eptdev = filp->private_data; + void *kbuf; + int ret; + + kbuf = memdup_user(buf, len); + if (IS_ERR(kbuf)) + return PTR_ERR(kbuf); + + if (mutex_lock_interruptible(&eptdev->ept_lock)) { + ret = -ERESTARTSYS; + goto free_kbuf; + } + + if (!eptdev->ept) { + ret = -EPIPE; + goto unlock_eptdev; + } + + if (filp->f_flags & O_NONBLOCK) + ret = rpmsg_trysend(eptdev->ept, kbuf, len); + else + ret = rpmsg_send(eptdev->ept, kbuf, len); + +unlock_eptdev: + mutex_unlock(&eptdev->ept_lock); + +free_kbuf: + kfree(kbuf); + return ret < 0 ? ret : len; +} + +static unsigned int rpmsg_eptdev_poll(struct file *filp, poll_table *wait) +{ + struct rpmsg_eptdev *eptdev = filp->private_data; + unsigned int mask = 0; + + if (!eptdev->ept) + return POLLERR; + + poll_wait(filp, &eptdev->readq, wait); + + if (!skb_queue_empty(&eptdev->queue)) + mask |= POLLIN | POLLRDNORM; + + mask |= rpmsg_poll(eptdev->ept, filp, wait); + + return mask; +} + +static long rpmsg_eptdev_ioctl(struct file *fp, unsigned int cmd, + unsigned long arg) +{ + struct rpmsg_eptdev *eptdev = fp->private_data; + + if (cmd != RPMSG_DESTROY_EPT_IOCTL) + return -EINVAL; + + return rpmsg_eptdev_destroy(&eptdev->dev, NULL); +} + +static const struct file_operations rpmsg_eptdev_fops = { + .owner = THIS_MODULE, + .open = rpmsg_eptdev_open, + .release = rpmsg_eptdev_release, + .read = rpmsg_eptdev_read, + .write = rpmsg_eptdev_write, + .poll = rpmsg_eptdev_poll, + .unlocked_ioctl = rpmsg_eptdev_ioctl, +}; + +static ssize_t name_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev); + + return sprintf(buf, "%s\n", eptdev->chinfo.name); +} +static DEVICE_ATTR_RO(name); + +static ssize_t src_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev); + + return sprintf(buf, "%d\n", eptdev->chinfo.src); +} +static DEVICE_ATTR_RO(src); + +static ssize_t dst_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev); + + return sprintf(buf, "%d\n", eptdev->chinfo.dst); +} +static DEVICE_ATTR_RO(dst); + +static struct attribute *rpmsg_eptdev_attrs[] = { + &dev_attr_name.attr, + &dev_attr_src.attr, + &dev_attr_dst.attr, + NULL +}; +ATTRIBUTE_GROUPS(rpmsg_eptdev); + +static void rpmsg_eptdev_release_device(struct device *dev) +{ + struct rpmsg_eptdev *eptdev = dev_to_eptdev(dev); + + ida_simple_remove(&rpmsg_ept_ida, dev->id); + ida_simple_remove(&rpmsg_minor_ida, MINOR(eptdev->dev.devt)); + cdev_del(&eptdev->cdev); + kfree(eptdev); +} + +static int rpmsg_eptdev_create(struct rpmsg_ctrldev *ctrldev, + struct rpmsg_channel_info chinfo) +{ + struct rpmsg_device *rpdev = ctrldev->rpdev; + struct rpmsg_eptdev *eptdev; + struct device *dev; + int ret; + + eptdev = kzalloc(sizeof(*eptdev), GFP_KERNEL); + if (!eptdev) + return -ENOMEM; + + dev = &eptdev->dev; + eptdev->rpdev = rpdev; + eptdev->chinfo = chinfo; + + mutex_init(&eptdev->ept_lock); + spin_lock_init(&eptdev->queue_lock); + skb_queue_head_init(&eptdev->queue); + init_waitqueue_head(&eptdev->readq); + + device_initialize(dev); + dev->class = rpmsg_class; + dev->parent = &ctrldev->dev; + dev->groups = rpmsg_eptdev_groups; + dev_set_drvdata(dev, eptdev); + + cdev_init(&eptdev->cdev, &rpmsg_eptdev_fops); + eptdev->cdev.owner = THIS_MODULE; + + ret = ida_simple_get(&rpmsg_minor_ida, 0, RPMSG_DEV_MAX, GFP_KERNEL); + if (ret < 0) + goto free_eptdev; + dev->devt = MKDEV(MAJOR(rpmsg_major), ret); + + ret = ida_simple_get(&rpmsg_ept_ida, 0, 0, GFP_KERNEL); + if (ret < 0) + goto free_minor_ida; + dev->id = ret; + dev_set_name(dev, "rpmsg%d", ret); + + ret = cdev_add(&eptdev->cdev, dev->devt, 1); + if (ret) + goto free_ept_ida; + + /* We can now rely on the release function for cleanup */ + dev->release = rpmsg_eptdev_release_device; + + ret = device_add(dev); + if (ret) { + dev_err(dev, "device_register failed: %d\n", ret); + put_device(dev); + } + + return ret; + +free_ept_ida: + ida_simple_remove(&rpmsg_ept_ida, dev->id); +free_minor_ida: + ida_simple_remove(&rpmsg_minor_ida, MINOR(dev->devt)); +free_eptdev: + put_device(dev); + kfree(eptdev); + + return ret; +} + +static int rpmsg_ctrldev_open(struct inode *inode, struct file *filp) +{ + struct rpmsg_ctrldev *ctrldev = cdev_to_ctrldev(inode->i_cdev); + + get_device(&ctrldev->dev); + filp->private_data = ctrldev; + + return 0; +} + +static int rpmsg_ctrldev_release(struct inode *inode, struct file *filp) +{ + struct rpmsg_ctrldev *ctrldev = cdev_to_ctrldev(inode->i_cdev); + + put_device(&ctrldev->dev); + + return 0; +} + +static long rpmsg_ctrldev_ioctl(struct file *fp, unsigned int cmd, + unsigned long arg) +{ + struct rpmsg_ctrldev *ctrldev = fp->private_data; + void __user *argp = (void __user *)arg; + struct rpmsg_endpoint_info eptinfo; + struct rpmsg_channel_info chinfo; + + if (cmd != RPMSG_CREATE_EPT_IOCTL) + return -EINVAL; + + if (copy_from_user(&eptinfo, argp, sizeof(eptinfo))) + return -EFAULT; + + memcpy(chinfo.name, eptinfo.name, RPMSG_NAME_SIZE); + chinfo.name[RPMSG_NAME_SIZE-1] = '\0'; + chinfo.src = eptinfo.src; + chinfo.dst = eptinfo.dst; + + return rpmsg_eptdev_create(ctrldev, chinfo); +}; + +static const struct file_operations rpmsg_ctrldev_fops = { + .owner = THIS_MODULE, + .open = rpmsg_ctrldev_open, + .release = rpmsg_ctrldev_release, + .unlocked_ioctl = rpmsg_ctrldev_ioctl, +}; + +static void rpmsg_ctrldev_release_device(struct device *dev) +{ + struct rpmsg_ctrldev *ctrldev = dev_to_ctrldev(dev); + + ida_simple_remove(&rpmsg_ctrl_ida, dev->id); + ida_simple_remove(&rpmsg_minor_ida, MINOR(dev->devt)); + cdev_del(&ctrldev->cdev); + kfree(ctrldev); +} + +static int rpmsg_chrdev_probe(struct rpmsg_device *rpdev) +{ + struct rpmsg_ctrldev *ctrldev; + struct device *dev; + int ret; + + ctrldev = kzalloc(sizeof(*ctrldev), GFP_KERNEL); + if (!ctrldev) + return -ENOMEM; + + ctrldev->rpdev = rpdev; + + dev = &ctrldev->dev; + device_initialize(dev); + dev->parent = &rpdev->dev; + dev->class = rpmsg_class; + + cdev_init(&ctrldev->cdev, &rpmsg_ctrldev_fops); + ctrldev->cdev.owner = THIS_MODULE; + + ret = ida_simple_get(&rpmsg_minor_ida, 0, RPMSG_DEV_MAX, GFP_KERNEL); + if (ret < 0) + goto free_ctrldev; + dev->devt = MKDEV(MAJOR(rpmsg_major), ret); + + ret = ida_simple_get(&rpmsg_ctrl_ida, 0, 0, GFP_KERNEL); + if (ret < 0) + goto free_minor_ida; + dev->id = ret; + dev_set_name(&ctrldev->dev, "rpmsg_ctrl%d", ret); + + ret = cdev_add(&ctrldev->cdev, dev->devt, 1); + if (ret) + goto free_ctrl_ida; + + /* We can now rely on the release function for cleanup */ + dev->release = rpmsg_ctrldev_release_device; + + ret = device_add(dev); + if (ret) { + dev_err(&rpdev->dev, "device_register failed: %d\n", ret); + put_device(dev); + } + + dev_set_drvdata(&rpdev->dev, ctrldev); + + return ret; + +free_ctrl_ida: + ida_simple_remove(&rpmsg_ctrl_ida, dev->id); +free_minor_ida: + ida_simple_remove(&rpmsg_minor_ida, MINOR(dev->devt)); +free_ctrldev: + put_device(dev); + kfree(ctrldev); + + return ret; +} + +static void rpmsg_chrdev_remove(struct rpmsg_device *rpdev) +{ + struct rpmsg_ctrldev *ctrldev = dev_get_drvdata(&rpdev->dev); + int ret; + + /* Destroy all endpoints */ + ret = device_for_each_child(&ctrldev->dev, NULL, rpmsg_eptdev_destroy); + if (ret) + dev_warn(&rpdev->dev, "failed to nuke endpoints: %d\n", ret); + + device_del(&ctrldev->dev); + put_device(&ctrldev->dev); +} + +static struct rpmsg_driver rpmsg_chrdev_driver = { + .probe = rpmsg_chrdev_probe, + .remove = rpmsg_chrdev_remove, + .drv = { + .name = "rpmsg_chrdev", + }, +}; + +static int rpmsg_char_init(void) +{ + int ret; + + ret = alloc_chrdev_region(&rpmsg_major, 0, RPMSG_DEV_MAX, "rpmsg"); + if (ret < 0) { + pr_err("rpmsg: failed to allocate char dev region\n"); + return ret; + } + + rpmsg_class = class_create(THIS_MODULE, "rpmsg"); + if (IS_ERR(rpmsg_class)) { + pr_err("failed to create rpmsg class\n"); + unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX); + return PTR_ERR(rpmsg_class); + } + + ret = register_rpmsg_driver(&rpmsg_chrdev_driver); + if (ret < 0) { + pr_err("rpmsgchr: failed to register rpmsg driver\n"); + class_destroy(rpmsg_class); + unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX); + } + + return ret; +} +postcore_initcall(rpmsg_char_init); + +static void rpmsg_chrdev_exit(void) +{ + unregister_rpmsg_driver(&rpmsg_chrdev_driver); + class_destroy(rpmsg_class); + unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX); +} +module_exit(rpmsg_chrdev_exit); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h index 6176f2457b6b..0cf9c7e2ee83 100644 --- a/drivers/rpmsg/rpmsg_internal.h +++ b/drivers/rpmsg/rpmsg_internal.h @@ -82,4 +82,19 @@ int rpmsg_unregister_device(struct device *parent, struct device *rpmsg_find_device(struct device *parent, struct rpmsg_channel_info *chinfo); +/** + * rpmsg_chrdev_register_device() - register chrdev device based on rpdev + * @rpdev: prepared rpdev to be used for creating endpoints + * + * This function wraps rpmsg_register_device() preparing the rpdev for use as + * basis for the rpmsg chrdev. + */ +static inline int rpmsg_chrdev_register_device(struct rpmsg_device *rpdev) +{ + strcpy(rpdev->id.name, "rpmsg_chrdev"); + rpdev->driver_override = "rpmsg_chrdev"; + + return rpmsg_register_device(rpdev); +} + #endif |