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linux/drivers/mmc/host/s3cmci.h
Ben Dooks 68c5ed592f s3cmci: DMA fixes
Fixes for the DMA transfer mode of the driver to try and improve the state
of the code:

- Ensure that dma_complete is set during the end of the command phase
  so that transfers do not stall awaiting the completion

- Update the DMA debugging to provide a bit more useful information
  such as how many DMA descriptors where not processed and print the
  DMA addresses in hexadecimal.

- Fix the DMA channel request code to actually request DMA for the
  S3CMCI block instead of whatever '0' signified.

- Add fallback to PIO if we cannot get the DMA channel, as many of the
  devices with this block only have a limited number of DMA channels.

- Only try and claim and free the DMA channel if we are trying to use it.

This improves the driver DMA code to the point where it can now identify a
card and read the partition table.  However the DMA can still stall when
trying to move data between the host and memory.

Signed-off-by: Ben Dooks <ben@simtec.co.uk>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-01 16:11:15 -07:00

83 lines
1.6 KiB
C

/*
* linux/drivers/mmc/s3cmci.h - Samsung S3C MCI driver
*
* Copyright (C) 2004-2006 Thomas Kleffel, All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
enum s3cmci_waitfor {
COMPLETION_NONE,
COMPLETION_FINALIZE,
COMPLETION_CMDSENT,
COMPLETION_RSPFIN,
COMPLETION_XFERFINISH,
COMPLETION_XFERFINISH_RSPFIN,
};
struct s3cmci_host {
struct platform_device *pdev;
struct s3c24xx_mci_pdata *pdata;
struct mmc_host *mmc;
struct resource *mem;
struct clk *clk;
void __iomem *base;
int irq;
int irq_cd;
int dma;
unsigned long clk_rate;
unsigned long clk_div;
unsigned long real_rate;
u8 prescaler;
int is2440;
unsigned sdiimsk;
unsigned sdidata;
int dodma;
int dmatogo;
bool irq_disabled;
bool irq_enabled;
bool irq_state;
int sdio_irqen;
struct mmc_request *mrq;
int cmd_is_stop;
spinlock_t complete_lock;
enum s3cmci_waitfor complete_what;
int dma_complete;
u32 pio_sgptr;
u32 pio_bytes;
u32 pio_count;
u32 *pio_ptr;
#define XFER_NONE 0
#define XFER_READ 1
#define XFER_WRITE 2
u32 pio_active;
int bus_width;
char dbgmsg_cmd[301];
char dbgmsg_dat[301];
char *status;
unsigned int ccnt, dcnt;
struct tasklet_struct pio_tasklet;
#ifdef CONFIG_DEBUG_FS
struct dentry *debug_root;
struct dentry *debug_state;
struct dentry *debug_regs;
#endif
#ifdef CONFIG_CPU_FREQ
struct notifier_block freq_transition;
#endif
};