saa7146_core.c

来自「trident tm5600的linux驱动」· C语言 代码 · 共 602 行 · 第 1/2 页

/*
    saa7146.o - driver for generic saa7146-based hardware

    Copyright (C) 1998-2003 Michael Hunold <[e-mail]>

    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; either version 2 of the License, or
    (at your option) any later version.

    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, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include <media/saa7146.h>

LIST_HEAD(saa7146_devices);
DEFINE_MUTEX(saa7146_devices_lock);

static int saa7146_num;

unsigned int saa7146_debug;

module_param(saa7146_debug, uint, 0644);
MODULE_PARM_DESC(saa7146_debug, "debug level (default: 0)");

#if 0 /* keep */
static void dump_registers(struct saa7146_dev* dev)
{
	int i = 0;

	INFO((" @ %li jiffies:\n",jiffies));
	for(i = 0; i <= 0x148; i+=4) {
		printk("0x%03x: 0x%08x\n",i,saa7146_read(dev,i));
	}
}
#endif

/****************************************************************************
 * gpio and debi helper functions
 ****************************************************************************/

void saa7146_setgpio(struct saa7146_dev *dev, int port, u32 data)
{
	u32 value = 0;

	BUG_ON(port > 3);

	value = saa7146_read(dev, GPIO_CTRL);
	value &= ~(0xff << (8*port));
	value |= (data << (8*port));
	saa7146_write(dev, GPIO_CTRL, value);
}

/* This DEBI code is based on the saa7146 Stradis driver by Nathan Laredo */
static inline int saa7146_wait_for_debi_done_sleep(struct saa7146_dev *dev,
				unsigned long us1, unsigned long us2)
{
	unsigned long timeout;
	int err;

	/* wait for registers to be programmed */
	timeout = jiffies + usecs_to_jiffies(us1);
	while (1) {
		err = time_after(jiffies, timeout);
		if (saa7146_read(dev, MC2) & 2)
			break;
		if (err) {
			printk(KERN_ERR "%s: %s timed out while waiting for "
					"registers getting programmed\n",
					dev->name, __func__);
			return -ETIMEDOUT;
		}
		msleep(1);
	}

	/* wait for transfer to complete */
	timeout = jiffies + usecs_to_jiffies(us2);
	while (1) {
		err = time_after(jiffies, timeout);
		if (!(saa7146_read(dev, PSR) & SPCI_DEBI_S))
			break;
		saa7146_read(dev, MC2);
		if (err) {
			DEB_S(("%s: %s timed out while waiting for transfer "
				"completion\n",	dev->name, __func__));
			return -ETIMEDOUT;
		}
		msleep(1);
	}

	return 0;
}

static inline int saa7146_wait_for_debi_done_busyloop(struct saa7146_dev *dev,
				unsigned long us1, unsigned long us2)
{
	unsigned long loops;

	/* wait for registers to be programmed */
	loops = us1;
	while (1) {
		if (saa7146_read(dev, MC2) & 2)
			break;
		if (!loops--) {
			printk(KERN_ERR "%s: %s timed out while waiting for "
					"registers getting programmed\n",
					dev->name, __func__);
			return -ETIMEDOUT;
		}
		udelay(1);
	}

	/* wait for transfer to complete */
	loops = us2 / 5;
	while (1) {
		if (!(saa7146_read(dev, PSR) & SPCI_DEBI_S))
			break;
		saa7146_read(dev, MC2);
		if (!loops--) {
			DEB_S(("%s: %s timed out while waiting for transfer "
				"completion\n", dev->name, __func__));
			return -ETIMEDOUT;
		}
		udelay(5);
	}

	return 0;
}

int saa7146_wait_for_debi_done(struct saa7146_dev *dev, int nobusyloop)
{
	if (nobusyloop)
		return saa7146_wait_for_debi_done_sleep(dev, 50000, 250000);
	else
		return saa7146_wait_for_debi_done_busyloop(dev, 50000, 250000);
}

/****************************************************************************
 * general helper functions
 ****************************************************************************/

/* this is videobuf_vmalloc_to_sg() from videobuf-dma-sg.c
   make sure virt has been allocated with vmalloc_32(), otherwise the BUG()
   may be triggered on highmem machines */
static struct scatterlist* vmalloc_to_sg(unsigned char *virt, int nr_pages)
{
	struct scatterlist *sglist;
	struct page *pg;
	int i;

	sglist = kcalloc(nr_pages, sizeof(struct scatterlist), GFP_KERNEL);
	if (NULL == sglist)
		return NULL;
	sg_init_table(sglist, nr_pages);
	for (i = 0; i < nr_pages; i++, virt += PAGE_SIZE) {
		pg = vmalloc_to_page(virt);
		if (NULL == pg)
			goto err;
		BUG_ON(PageHighMem(pg));
		sg_set_page(&sglist[i], pg, PAGE_SIZE, 0);
	}
	return sglist;

 err:
	kfree(sglist);
	return NULL;
}

/********************************************************************************/
/* common page table functions */

void *saa7146_vmalloc_build_pgtable(struct pci_dev *pci, long length, struct saa7146_pgtable *pt)
{
	int pages = (length+PAGE_SIZE-1)/PAGE_SIZE;
	void *mem = vmalloc_32(length);
	int slen = 0;

	if (NULL == mem)
		goto err_null;

	if (!(pt->slist = vmalloc_to_sg(mem, pages)))
		goto err_free_mem;

	if (saa7146_pgtable_alloc(pci, pt))
		goto err_free_slist;

	pt->nents = pages;
	slen = pci_map_sg(pci,pt->slist,pt->nents,PCI_DMA_FROMDEVICE);
	if (0 == slen)
		goto err_free_pgtable;

	if (0 != saa7146_pgtable_build_single(pci, pt, pt->slist, slen))
		goto err_unmap_sg;

	return mem;

err_unmap_sg:
	pci_unmap_sg(pci, pt->slist, pt->nents, PCI_DMA_FROMDEVICE);
err_free_pgtable:
	saa7146_pgtable_free(pci, pt);
err_free_slist:
	kfree(pt->slist);
	pt->slist = NULL;
err_free_mem:
	vfree(mem);
err_null:
	return NULL;
}

void saa7146_vfree_destroy_pgtable(struct pci_dev *pci, void *mem, struct saa7146_pgtable *pt)
{
	pci_unmap_sg(pci, pt->slist, pt->nents, PCI_DMA_FROMDEVICE);
	saa7146_pgtable_free(pci, pt);
	kfree(pt->slist);
	pt->slist = NULL;
	vfree(mem);
}

void saa7146_pgtable_free(struct pci_dev *pci, struct saa7146_pgtable *pt)
{
	if (NULL == pt->cpu)
		return;
	pci_free_consistent(pci, pt->size, pt->cpu, pt->dma);
	pt->cpu = NULL;
}

int saa7146_pgtable_alloc(struct pci_dev *pci, struct saa7146_pgtable *pt)
{
	__le32       *cpu;
	dma_addr_t   dma_addr = 0;

	cpu = pci_alloc_consistent(pci, PAGE_SIZE, &dma_addr);
	if (NULL == cpu) {
		return -ENOMEM;
	}
	pt->size = PAGE_SIZE;
	pt->cpu  = cpu;
	pt->dma  = dma_addr;

	return 0;
}

int saa7146_pgtable_build_single(struct pci_dev *pci, struct saa7146_pgtable *pt,
	struct scatterlist *list, int sglen  )
{
	__le32 *ptr, fill;
	int nr_pages = 0;
	int i,p;

	BUG_ON(0 == sglen);
	BUG_ON(list->offset > PAGE_SIZE);

	/* if we have a user buffer, the first page may not be
	   aligned to a page boundary. */
	pt->offset = list->offset;

	ptr = pt->cpu;
	for (i = 0; i < sglen; i++, list++) {
/*
		printk("i:%d, adr:0x%08x, len:%d, offset:%d\n", i,sg_dma_address(list), sg_dma_len(list), list->offset);
*/
		for (p = 0; p * 4096 < list->length; p++, ptr++) {
			*ptr = cpu_to_le32(sg_dma_address(list) + p * 4096);
			nr_pages++;
		}
	}


	/* safety; fill the page table up with the last valid page */
	fill = *(ptr-1);
	for(i=nr_pages;i<1024;i++) {
		*ptr++ = fill;
	}

/*
	ptr = pt->cpu;
	printk("offset: %d\n",pt->offset);
	for(i=0;i<5;i++) {
		printk("ptr1 %d: 0x%08x\n",i,ptr[i]);
	}
*/
	return 0;
}

/********************************************************************************/
/* interrupt handler */
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,19)
static irqreturn_t interrupt_hw(int irq, void *dev_id, struct pt_regs *regs)
#else
static irqreturn_t interrupt_hw(int irq, void *dev_id)
#endif
{
	struct saa7146_dev *dev = dev_id;
	u32 isr;