vdec_drv.zip_vdec_video decoder

/* * Copyright (c) 2013. Internet Technology Laboratory, ITLAB * Dept. of Electrical Engineering & Inst. of Computer and Communication Engineering * National Cheng Kung University, Tainan, Taiwan * All Right Reserved * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License 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. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include <linux/init.h> #include <linux/module.h> #include <linux/types.h> #include <linux/fs.h> #include <linux/cdev.h> #include <linux/ioctl.h> #include <linux/wait.h> #include <linux/mm.h> #include <asm/uaccess.h> #include <asm/atomic.h> #include <asm/io.h> #include <asm/page.h> #include <linux/device.h> #include <asm/irq.h> #include <linux/sched.h> #include <linux/interrupt.h> #include <linux/irqflags.h> #include <linux/wait.h> /* hardware device setting value */ #define DRIVER_NAME "vdec_hw" #define DEVICE_NAME "vdec" #define VDEC_MAJOR 256 #define VDEC_MINOR 0 #define IRQ_VIC_BRIDGE 30 #define PIC_BASE 32 #define VDEC_BASE 0x80000000 #define MEMSIZE 0x1000 #define BUFSIZE 384 /* command */ #define OP_SET 1 #define GO 5 /* address offset */ #define operator_offset 0x4 #define ibuffer_offset 0xC #define obuffer_offset 0x614 #define CHECKFLAG_OFFSET 0x60C #define SIZECOUNT_OFFSET 0x610 #define interrupt_offset 0xD00 MODULE_AUTHOR("Drunkard"); MODULE_LICENSE("GPL"); static DECLARE_WAIT_QUEUE_HEAD(wq); static int flag = 0; static int vdec_major = VDEC_MAJOR; static int vdec_minor = VDEC_MINOR; static int buffer[BUFSIZE+2]; void __iomem *base; static int vdec_open(struct inode *inode, struct file *file) { return 0; } static int vdec_release(struct inode *inode, struct file *file) { return 0; } static ssize_t vdec_read(struct file *filp, char *buff, size_t len, loff_t *off) { int i; /* Only result is readable memory address */ if(len > BUFSIZE*4) len = BUFSIZE*4; for(i=0;i<len/4;i++) buffer[i] = readl(base + obuffer_offset + i*4); buffer[BUFSIZE] = readl(base + SIZECOUNT_OFFSET); buffer[BUFSIZE+1] = readl(base + CHECKFLAG_OFFSET); i = copy_to_user(buff, buffer, len+8); return len; } static ssize_t vdec_write(struct file *filp, const char *buff, size_t len, loff_t *off) { int i; if(len > BUFSIZE*4) len = BUFSIZE*4; i = copy_from_user(buffer, buff, len); for(i=0;i<len/4;i++) { writel(buffer[i], base + ibuffer_offset + i*4); } return len; } static long vdec_unlocked_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { switch(cmd) { case OP_SET: writel((unsigned int)arg, base + operator_offset); break; case GO: writel((unsigned int)arg, base); wait_event_interruptible(wq, flag != 0); flag = 0; break; default: printk("Unknown COMMAND!!!\n"); } return 0; } static void allocate_memory_region(void) { base = ioremap_nocache(VDEC_BASE , MEMSIZE); printk("Physical address: %08X-%08X (%dKB)\n", VDEC_BASE, VDEC_BASE+MEMSIZE, MEMSIZE/1024); printk("After ioremap: %08X-%08X (%dKB)\n", (int)base, (int)base+MEMSIZE, MEMSIZE/1024); } static void free_allocated_memory(void) { iounmap((unsigned long*) base); } static struct file_operations vdec_fops = { .owner = THIS_MODULE, .read = vdec_read, .write = vdec_write, .unlocked_ioctl = vdec_unlocked_ioctl, .open = vdec_open, .release = vdec_release }; static struct cdev vdec_cdev = { .kobj = { .name = DRIVER_NAME }, .owner = THIS_MODULE, }; static irqreturn_t vdec_interrupt(int irq, void *dev_id, struct pt_regs *regs) { //printk("received interrupt from SC_LINK\n"); if(irq == IRQ_VIC_BRIDGE+PIC_BASE) { //printk("received interrupt from MP3EN HW\n"); writel(0, base+interrupt_offset); //printk("Release interrupt\n"); flag = 1; wake_up_interruptible(&wq); } return IRQ_HANDLED; } static int __init vdec_init(void) { dev_t dev = 0; int result; /* register char device */ if(VDEC_MAJOR) { dev = MKDEV(vdec_major, vdec_minor); result = register_chrdev_region(dev, 1, DRIVER_NAME); } else { result = alloc_chrdev_region(&dev, vdec_minor, 1, DRIVER_NAME); vdec_major = MAJOR(dev); } if(result < 0) { printk(KERN_ERR DRIVER_NAME "Can't allocate major number %d for %s\n", vdec_major, DEVICE_NAME); return -EAGAIN; } cdev_init(&vdec_cdev, &vdec_fops); result = cdev_add(&vdec_cdev, dev, 1); if(result < 0) { printk(KERN_ERR DRIVER_NAME "Can't add device %d\n", dev); return -EAGAIN; } /* allocate memory */ allocate_memory_region(); /* request irq and bind ISR*/ result = request_irq(IRQ_VIC_BRIDGE+PIC_BASE, (void*)vdec_interrupt, IRQF_DISABLED, DEVICE_NAME, NULL); if(result) printk(KERN_ERR DRIVER_NAME "Can't request IRQ\n"); return 0; } static void __exit vdec_exit(void){ dev_t dev; free_allocated_memory(); dev = MKDEV(vdec_major, vdec_minor); unregister_chrdev_region(dev, 1); cdev_del(&vdec_cdev); free_irq(IRQ_VIC_BRIDGE+PIC_BASE, NULL); printk("VDEC driver exit\n"); } module_init(vdec_init); module_exit(vdec_exit);