+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
-/**
- * rpivid-mem.c - character device access to the RPiVid decoder registers
- *
- * Based on bcm2835-gpiomem.c. Provides IO memory access to the decoder
- * register blocks such that ffmpeg plugins can access the hardware.
- *
- * Jonathan Bell <jonathan@raspberrypi.org>
- * Copyright (c) 2019, Raspberry Pi (Trading) Ltd.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions, and the following disclaimer,
- * without modification.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. The names of the above-listed copyright holders may not be used
- * to endorse or promote products derived from this software without
- * specific prior written permission.
- *
- * ALTERNATIVELY, this software may be distributed under the terms of the
- * GNU General Public License ("GPL") version 2, as published by the Free
- * Software Foundation.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
- * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
- * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
- * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
- * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
- * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
- * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
- * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
- * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/of.h>
-#include <linux/of_device.h>
-#include <linux/platform_device.h>
-#include <linux/mm.h>
-#include <linux/slab.h>
-#include <linux/cdev.h>
-#include <linux/pagemap.h>
-#include <linux/io.h>
-
-#define DRIVER_NAME "rpivid-mem"
-#define DEVICE_MINOR 0
-
-struct rpivid_mem_priv {
- dev_t devid;
- struct class *class;
- struct cdev rpivid_mem_cdev;
- unsigned long regs_phys;
- unsigned long mem_window_len;
- struct device *dev;
- const char *name;
-};
-
-static int rpivid_mem_open(struct inode *inode, struct file *file)
-{
- int dev = iminor(inode);
- int ret = 0;
- struct rpivid_mem_priv *priv;
-
- if (dev != DEVICE_MINOR && dev != DEVICE_MINOR + 1)
- ret = -ENXIO;
-
- priv = container_of(inode->i_cdev, struct rpivid_mem_priv,
- rpivid_mem_cdev);
- if (!priv)
- return -EINVAL;
- file->private_data = priv;
- return ret;
-}
-
-static int rpivid_mem_release(struct inode *inode, struct file *file)
-{
- int dev = iminor(inode);
- int ret = 0;
-
- if (dev != DEVICE_MINOR && dev != DEVICE_MINOR + 1)
- ret = -ENXIO;
-
- return ret;
-}
-
-static const struct vm_operations_struct rpivid_mem_vm_ops = {
-#ifdef CONFIG_HAVE_IOREMAP_PROT
- .access = generic_access_phys
-#endif
-};
-
-static int rpivid_mem_mmap(struct file *file, struct vm_area_struct *vma)
-{
- struct rpivid_mem_priv *priv;
- unsigned long pages;
- unsigned long len;
-
- priv = file->private_data;
- pages = priv->regs_phys >> PAGE_SHIFT;
- /*
- * The address decode is far larger than the actual number of registers.
- * Just map the whole lot in.
- */
- len = min(vma->vm_end - vma->vm_start, priv->mem_window_len);
- vma->vm_page_prot = phys_mem_access_prot(file, pages, len,
- vma->vm_page_prot);
- vma->vm_ops = &rpivid_mem_vm_ops;
- if (remap_pfn_range(vma, vma->vm_start,
- pages, len,
- vma->vm_page_prot)) {
- return -EAGAIN;
- }
- return 0;
-}
-
-static const struct file_operations
-rpivid_mem_fops = {
- .owner = THIS_MODULE,
- .open = rpivid_mem_open,
- .release = rpivid_mem_release,
- .mmap = rpivid_mem_mmap,
-};
-
-static const struct of_device_id rpivid_mem_of_match[];
-static int rpivid_mem_probe(struct platform_device *pdev)
-{
- int err;
- const struct of_device_id *id;
- struct device *dev = &pdev->dev;
- struct resource *ioresource;
- struct rpivid_mem_priv *priv;
-
- /* Allocate buffers and instance data */
-
- priv = kzalloc(sizeof(struct rpivid_mem_priv), GFP_KERNEL);
-
- if (!priv) {
- err = -ENOMEM;
- goto failed_inst_alloc;
- }
- platform_set_drvdata(pdev, priv);
-
- priv->dev = dev;
- id = of_match_device(rpivid_mem_of_match, dev);
- if (!id)
- return -EINVAL;
- priv->name = id->data;
-
- ioresource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (ioresource) {
- priv->regs_phys = ioresource->start;
- priv->mem_window_len = (ioresource->end + 1) - ioresource->start;
- } else {
- dev_err(priv->dev, "failed to get IO resource");
- err = -ENOENT;
- goto failed_get_resource;
- }
-
- /* Create character device entries */
-
- err = alloc_chrdev_region(&priv->devid,
- DEVICE_MINOR, 2, priv->name);
- if (err != 0) {
- dev_err(priv->dev, "unable to allocate device number");
- goto failed_alloc_chrdev;
- }
- cdev_init(&priv->rpivid_mem_cdev, &rpivid_mem_fops);
- priv->rpivid_mem_cdev.owner = THIS_MODULE;
- err = cdev_add(&priv->rpivid_mem_cdev, priv->devid, 2);
- if (err != 0) {
- dev_err(priv->dev, "unable to register device");
- goto failed_cdev_add;
- }
-
- /* Create sysfs entries */
-
- priv->class = class_create(priv->name);
- if (IS_ERR(priv->class)) {
- err = PTR_ERR(priv->class);
- goto failed_class_create;
- }
-
- dev = device_create(priv->class, NULL, priv->devid, NULL, priv->name);
- if (IS_ERR(dev)) {
- err = PTR_ERR(dev);
- goto failed_device_create;
- }
-
- dev_info(priv->dev, "%s initialised: Registers at 0x%08lx length 0x%08lx",
- priv->name, priv->regs_phys, priv->mem_window_len);
-
- return 0;
-
-failed_device_create:
- class_destroy(priv->class);
-failed_class_create:
- cdev_del(&priv->rpivid_mem_cdev);
-failed_cdev_add:
- unregister_chrdev_region(priv->devid, 1);
-failed_alloc_chrdev:
-failed_get_resource:
- kfree(priv);
-failed_inst_alloc:
- dev_err(&pdev->dev, "could not load rpivid_mem");
- return err;
-}
-
-static int rpivid_mem_remove(struct platform_device *pdev)
-{
- struct device *dev = &pdev->dev;
- struct rpivid_mem_priv *priv = platform_get_drvdata(pdev);
-
- device_destroy(priv->class, priv->devid);
- class_destroy(priv->class);
- cdev_del(&priv->rpivid_mem_cdev);
- unregister_chrdev_region(priv->devid, 1);
- kfree(priv);
-
- dev_info(dev, "%s driver removed - OK", priv->name);
- return 0;
-}
-
-static const struct of_device_id rpivid_mem_of_match[] = {
- {
- .compatible = "raspberrypi,rpivid-hevc-decoder",
- .data = "rpivid-hevcmem",
- },
- {
- .compatible = "raspberrypi,rpivid-h264-decoder",
- .data = "rpivid-h264mem",
- },
- {
- .compatible = "raspberrypi,rpivid-vp9-decoder",
- .data = "rpivid-vp9mem",
- },
- /* The "intc" is included as this block of hardware contains the
- * "frame done" status flags.
- */
- {
- .compatible = "raspberrypi,rpivid-local-intc",
- .data = "rpivid-intcmem",
- },
- { /* sentinel */ },
-};
-
-MODULE_DEVICE_TABLE(of, rpivid_mem_of_match);
-
-static struct platform_driver rpivid_mem_driver = {
- .probe = rpivid_mem_probe,
- .remove = rpivid_mem_remove,
- .driver = {
- .name = DRIVER_NAME,
- .owner = THIS_MODULE,
- .of_match_table = rpivid_mem_of_match,
- },
-};
-
-module_platform_driver(rpivid_mem_driver);
-
-MODULE_ALIAS("platform:rpivid-mem");
-MODULE_LICENSE("GPL");
-MODULE_DESCRIPTION("Driver for accessing RPiVid decoder registers from userspace");
-MODULE_AUTHOR("Jonathan Bell <jonathan@raspberrypi.org>");
projects / platform / kernel / linux-rpi.git / commitdiff