path: root/drivers/mmc/host/tifm_sd.c

/*
 *  tifm_sd.c - TI FlashMedia driver
 *
 *  Copyright (C) 2006 Alex Dubov <oakad@yahoo.com>
 *
 * 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.
 *
 * Special thanks to Brad Campbell for extensive testing of this driver.
 *
 */


#include <linux/tifm.h>
#include <linux/mmc/host.h>
#include <linux/highmem.h>
#include <linux/scatterlist.h>
#include <asm/io.h>

#define DRIVER_NAME "tifm_sd"
#define DRIVER_VERSION "0.8"

static int no_dma = 0;
static int fixed_timeout = 0;
module_param(no_dma, bool, 0644);
module_param(fixed_timeout, bool, 0644);

/* Constants here are mostly from OMAP5912 datasheet */
#define TIFM_MMCSD_RESET      0x0002
#define TIFM_MMCSD_CLKMASK    0x03ff
#define TIFM_MMCSD_POWER      0x0800
#define TIFM_MMCSD_4BBUS      0x8000
#define TIFM_MMCSD_RXDE       0x8000   /* rx dma enable */
#define TIFM_MMCSD_TXDE       0x0080   /* tx dma enable */
#define TIFM_MMCSD_BUFINT     0x0c00   /* set bits: AE, AF */
#define TIFM_MMCSD_DPE        0x0020   /* data timeout counted in kilocycles */
#define TIFM_MMCSD_INAB       0x0080   /* abort / initialize command */
#define TIFM_MMCSD_READ       0x8000

#define TIFM_MMCSD_ERRMASK    0x01e0   /* set bits: CCRC, CTO, DCRC, DTO */
#define TIFM_MMCSD_EOC        0x0001   /* end of command phase  */
#define TIFM_MMCSD_CD         0x0002   /* card detect           */
#define TIFM_MMCSD_CB         0x0004   /* card enter busy state */
#define TIFM_MMCSD_BRS        0x0008   /* block received/sent   */
#define TIFM_MMCSD_EOFB       0x0010   /* card exit busy state  */
#define TIFM_MMCSD_DTO        0x0020   /* data time-out         */
#define TIFM_MMCSD_DCRC       0x0040   /* data crc error        */
#define TIFM_MMCSD_CTO        0x0080   /* command time-out      */
#define TIFM_MMCSD_CCRC       0x0100   /* command crc error     */
#define TIFM_MMCSD_AF         0x0400   /* fifo almost full      */
#define TIFM_MMCSD_AE         0x0800   /* fifo almost empty     */
#define TIFM_MMCSD_OCRB       0x1000   /* OCR busy              */
#define TIFM_MMCSD_CIRQ       0x2000   /* card irq (cmd40/sdio) */
#define TIFM_MMCSD_CERR       0x4000   /* card status error     */

#define TIFM_MMCSD_ODTO       0x0040   /* open drain / extended timeout */
#define TIFM_MMCSD_CARD_RO    0x0200   /* card is read-only     */

#define TIFM_MMCSD_FIFO_SIZE  0x0020

#define TIFM_MMCSD_RSP_R0     0x0000
#define TIFM_MMCSD_RSP_R1     0x0100
#define TIFM_MMCSD_RSP_R2     0x0200
#define TIFM_MMCSD_RSP_R3     0x0300
#define TIFM_MMCSD_RSP_R4     0x0400
#define TIFM_MMCSD_RSP_R5     0x0500
#define TIFM_MMCSD_RSP_R6     0x0600

#define TIFM_MMCSD_RSP_BUSY   0x0800

#define TIFM_MMCSD_CMD_BC     0x0000
#define TIFM_MMCSD_CMD_BCR    0x1000
#define TIFM_MMCSD_CMD_AC     0x2000
#define TIFM_MMCSD_CMD_ADTC   0x3000

#define TIFM_MMCSD_MAX_BLOCK_SIZE  0x0800UL

enum {
	CMD_READY    = 0x0001,
	FIFO_READY   = 0x0002,
	BRS_READY    = 0x0004,
	SCMD_ACTIVE  = 0x0008,
	SCMD_READY   = 0x0010,
	CARD_BUSY    = 0x0020,
	DATA_CARRY   = 0x0040
};

struct tifm_sd {
	struct tifm_dev       *dev;

	unsigned short        eject:1,
			      open_drain:1,
			      no_dma:1;
	unsigned short        cmd_flags;

	unsigned int          clk_freq;
	unsigned int          clk_div;
	unsigned long         timeout_jiffies;

	struct tasklet_struct finish_tasklet;
	struct timer_list     timer;
	struct mmc_request    *req;

	int                   sg_len;
	int                   sg_pos;
	unsigned int          block_pos;
	struct scatterlist    bounce_buf;
	unsigned char         bounce_buf_data[TIFM_MMCSD_MAX_BLOCK_SIZE];
};

/* for some reason, host won't respond correctly to readw/writew */
static void tifm_sd_read_fifo(struct tifm_sd *host, struct page *pg,
			      unsigned int off, unsigned int cnt)
{
	struct tifm_dev *sock = host->dev;
	unsigned char *buf;
	unsigned int pos = 0, val;

	buf = kmap_atomic(pg, KM_BIO_DST_IRQ) + off;
	if (host->cmd_flags & DATA_CARRY) {
		buf[pos++] = host->bounce_buf_data[0];
		host->cmd_flags &= ~DATA_CARRY;
	}

	while (pos < cnt) {
		val = readl(sock->addr + SOCK_MMCSD_DATA);
		buf[pos++] = val & 0xff;
		if (pos == cnt) {
			host->bounce_buf_data[0] = (val >> 8) & 0xff;
			host->cmd_flags |= DATA_CARRY;
			break;
		}
		buf[pos++] = (val >> 8) & 0xff;
	}
	kunmap_atomic(buf - off, KM_BIO_DST_IRQ);
}

static void tifm_sd_write_fifo(struct tifm_sd *host, struct page *pg,
			       unsigned int off, unsigned int cnt)
{
	struct tifm_dev *sock = host->dev;
	unsigned char *buf;
	unsigned int pos = 0, val;

	buf = kmap_atomic