path: root/drivers/dma/coh901318.c

/*
 * driver/dma/coh901318.c
 *
 * Copyright (C) 2007-2009 ST-Ericsson
 * License terms: GNU General Public License (GPL) version 2
 * DMA driver for COH 901 318
 * Author: Per Friden <per.friden@stericsson.com>
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h> /* printk() */
#include <linux/fs.h> /* everything... */
#include <linux/scatterlist.h>
#include <linux/slab.h> /* kmalloc() */
#include <linux/dmaengine.h>
#include <linux/platform_device.h>
#include <linux/device.h>
#include <linux/irqreturn.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/uaccess.h>
#include <linux/debugfs.h>
#include <mach/coh901318.h>

#include "coh901318_lli.h"

#define COHC_2_DEV(cohc) (&cohc->chan.dev->device)

#ifdef VERBOSE_DEBUG
#define COH_DBG(x) ({ if (1) x; 0; })
#else
#define COH_DBG(x) ({ if (0) x; 0; })
#endif

struct coh901318_desc {
	struct dma_async_tx_descriptor desc;
	struct list_head node;
	struct scatterlist *sg;
	unsigned int sg_len;
	struct coh901318_lli *lli;
	enum dma_transfer_direction dir;
	unsigned long flags;
	u32 head_config;
	u32 head_ctrl;
};

struct coh901318_base {
	struct device *dev;
	void __iomem *virtbase;
	struct coh901318_pool pool;
	struct powersave pm;
	struct dma_device dma_slave;
	struct dma_device dma_memcpy;
	struct coh901318_chan *chans;
	struct coh901318_platform *platform;
};

struct coh901318_chan {
	spinlock_t lock;
	int allocated;
	int completed;
	int id;
	int stopped;

	struct work_struct free_work;
	struct dma_chan chan;

	struct tasklet_struct tasklet;

	struct list_head active;
	struct list_head queue;
	struct list_head free;

	unsigned long nbr_active_done;
	unsigned long busy;

	u32 runtime_addr;
	u32 runtime_ctrl;

	struct coh901318_base *base;
};

static void coh901318_list_print(struct coh901318_chan *cohc,
				 struct coh901318_lli *lli)
{
	struct coh901318_lli *l = lli;
	int i = 0;

	while (l) {
		dev_vdbg(COHC_2_DEV(cohc), "i %d, lli %p, ctrl 0x%x, src 0x%x"
			 ", dst 0x%x, link 0x%x virt_link_addr 0x%p\n",
			 i, l, l->control, l->src_addr, l->dst_addr,
			 l->link_addr, l->virt_link_addr);
		i++;
		l = l->virt_link_addr;
	}
}

#ifdef CONFIG_DEBUG_FS

#define COH901318_DEBUGFS_ASSIGN(x, y) (x = y)

static struct coh901318_base *debugfs_dma_base;
static struct dentry *dma_dentry;

static int coh901318_debugfs_open(struct inode *inode, struct file *file)
{

	file->private_data = inode->i_private;
	return 0;
}

static int coh901318_debugfs_read(struct file *file, char __user *buf,
				  size_t count, loff_t *f_pos)
{
	u64 started_channels = debugfs_dma_base->pm.started_channels;
	int pool_count = debugfs_dma_base->pool.debugfs_pool_counter;
	int i;
	int ret = 0;
	char *dev_buf;
	char *tmp;
	int dev_size;

	dev_buf = kmalloc(4*1024, GFP_KERNEL);
	if (dev_buf == NULL)
		goto err_kmalloc;
	tmp = dev_buf;

	tmp += sprintf(tmp, "DMA -- enabled dma channels\n");

	for (i = 0; i < debugfs_dma_base->platform->max_channels; i++)
		if (started_channels & (1 << i))
			tmp += sprintf(tmp, "channel %d\n", i);

	tmp += sprintf(tmp, "Pool alloc nbr %d\n", pool_count);
	dev_size = tmp  - dev_buf;

	/* No more to read if offset != 0 */
	if (*f_pos > dev_size)
		goto out;

	if (count > dev_size - *f_pos)
		count = dev_size - *f_pos;

	if (copy_to_user(buf, dev_buf + *f_pos, count))
		ret = -EINVAL;
	ret = count;
	*f_pos += count;

 out:
	kfree(dev_buf);
	return ret;

 err_kmalloc:
	return 0;
}

static const struct file_operations coh901318_debugfs_status_operations = {
	.owner		= THIS_MODULE,
	.open		= coh901318_debugfs_open,
	.read		= coh901318_debugfs_read,
	.llseek		= default_llseek,
};


static int __init init_coh901318_debugfs(void)
{

	dma_dentry = debugfs_create_dir("dma", NULL);

	(void) debugfs_create_file("status",
				   S_IFREG | S_IRUGO,
				   dma_dentry, NULL,
				   &coh901318_de