wbsd.c

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/*
 *  linux/drivers/mmc/wbsd.c - Winbond W83L51xD SD/MMC driver
 *
 *  Copyright (C) 2004-2005 Pierre Ossman, 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 as published by
 * the Free Software Foundation; either version 2 of the License, or (at
 * your option) any later version.
 *
 *
 * Warning!
 *
 * Changes to the FIFO system should be done with extreme care since
 * the hardware is full of bugs related to the FIFO. Known issues are:
 *
 * - FIFO size field in FSR is always zero.
 *
 * - FIFO interrupts tend not to work as they should. Interrupts are
 *   triggered only for full/empty events, not for threshold values.
 *
 * - On APIC systems the FIFO empty interrupt is sometimes lost.
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/dma-mapping.h>
#include <linux/delay.h>
#include <linux/pnp.h>
#include <linux/highmem.h>
#include <linux/mmc/host.h>
#include <linux/mmc/protocol.h>

#include <asm/io.h>
#include <asm/dma.h>
#include <asm/scatterlist.h>

#include "wbsd.h"

#define DRIVER_NAME "wbsd"
#define DRIVER_VERSION "1.6"

#define DBG(x...) \
	pr_debug(DRIVER_NAME ": " x)
#define DBGF(f, x...) \
	pr_debug(DRIVER_NAME " [%s()]: " f, __func__ , ##x)

/*
 * Device resources
 */

#ifdef CONFIG_PNP

static const struct pnp_device_id pnp_dev_table[] = {
	{ "WEC0517", 0 },
	{ "WEC0518", 0 },
	{ "", 0 },
};

MODULE_DEVICE_TABLE(pnp, pnp_dev_table);

#endif /* CONFIG_PNP */

static const int config_ports[] = { 0x2E, 0x4E };
static const int unlock_codes[] = { 0x83, 0x87 };

static const int valid_ids[] = {
	0x7112,
	};

#ifdef CONFIG_PNP
static unsigned int nopnp = 0;
#else
static const unsigned int nopnp = 1;
#endif
static unsigned int io = 0x248;
static unsigned int irq = 6;
static int dma = 2;

/*
 * Basic functions
 */

static inline void wbsd_unlock_config(struct wbsd_host *host)
{
	BUG_ON(host->config == 0);

	outb(host->unlock_code, host->config);
	outb(host->unlock_code, host->config);
}

static inline void wbsd_lock_config(struct wbsd_host *host)
{
	BUG_ON(host->config == 0);

	outb(LOCK_CODE, host->config);
}

static inline void wbsd_write_config(struct wbsd_host *host, u8 reg, u8 value)
{
	BUG_ON(host->config == 0);

	outb(reg, host->config);
	outb(value, host->config + 1);
}

static inline u8 wbsd_read_config(struct wbsd_host *host, u8 reg)
{
	BUG_ON(host->config == 0);

	outb(reg, host->config);
	return inb(host->config + 1);
}

static inline void wbsd_write_index(struct wbsd_host *host, u8 index, u8 value)
{
	outb(index, host->base + WBSD_IDXR);
	outb(value, host->base + WBSD_DATAR);
}

static inline u8 wbsd_read_index(struct wbsd_host *host, u8 index)
{
	outb(index, host->base + WBSD_IDXR);
	return inb(host->base + WBSD_DATAR);
}

/*
 * Common routines
 */

static void wbsd_init_device(struct wbsd_host *host)
{
	u8 setup, ier;

	/*
	 * Reset chip (SD/MMC part) and fifo.
	 */
	setup = wbsd_read_index(host, WBSD_IDX_SETUP);
	setup |= WBSD_FIFO_RESET | WBSD_SOFT_RESET;
	wbsd_write_index(host, WBSD_IDX_SETUP, setup);

	/*
	 * Set DAT3 to input
	 */
	setup &= ~WBSD_DAT3_H;
	wbsd_write_index(host, WBSD_IDX_SETUP, setup);
	host->flags &= ~WBSD_FIGNORE_DETECT;

	/*
	 * Read back default clock.
	 */
	host->clk = wbsd_read_index(host, WBSD_IDX_CLK);

	/*
	 * Power down port.
	 */
	outb(WBSD_POWER_N, host->base + WBSD_CSR);

	/*
	 * Set maximum timeout.
	 */
	wbsd_write_index(host, WBSD_IDX_TAAC, 0x7F);

	/*
	 * Test for card presence
	 */
	if (inb(host->base + WBSD_CSR) & WBSD_CARDPRESENT)
		host->flags |= WBSD_FCARD_PRESENT;
	else
		host->flags &= ~WBSD_FCARD_PRESENT;

	/*
	 * Enable interesting interrupts.
	 */
	ier = 0;
	ier |= WBSD_EINT_CARD;
	ier |= WBSD_EINT_FIFO_THRE;
	ier |= WBSD_EINT_CCRC;
	ier |= WBSD_EINT_TIMEOUT;
	ier |= WBSD_EINT_CRC;
	ier |= WBSD_EINT_TC;

	outb(ier, host->base + WBSD_EIR);

	/*
	 * Clear interrupts.
	 */
	inb(host->base + WBSD_ISR);
}

static void wbsd_reset(struct wbsd_host *host)
{
	u8 setup;

	printk(KERN_ERR "%s: Resetting chip\n", mmc_hostname(host->mmc));

	/*
	 * Soft reset of chip (SD/MMC part).
	 */
	setup = wbsd_read_index(host, WBSD_IDX_SETUP);
	setup |= WBSD_SOFT_RESET;
	wbsd_write_index(host, WBSD_IDX_SETUP, setup);
}

static void wbsd_request_end(struct wbsd_host *host, struct mmc_request *mrq)
{
	unsigned long dmaflags;

	DBGF("Ending request, cmd (%x)\n", mrq->cmd->opcode);

	if (host->dma >= 0) {
		/*
		 * Release ISA DMA controller.
		 */
		dmaflags = claim_dma_lock();
		disable_dma(host->dma);
		clear_dma_ff(host->dma);
		release_dma_lock(dmaflags);

		/*
		 * Disable DMA on host.
		 */
		wbsd_write_index(host, WBSD_IDX_DMA, 0);
	}

	host->mrq = NULL;

	/*
	 * MMC layer might call back into the driver so first unlock.
	 */
	spin_unlock(&host->lock);
	mmc_request_done(host->mmc, mrq);
	spin_lock(&host->lock);
}

/*
 * Scatter/gather functions
 */

static inline void wbsd_init_sg(struct wbsd_host *host, struct mmc_data *data)
{
	/*
	 * Get info. about SG list from data structure.
	 */
	host->cur_sg = data->sg;
	host->num_sg = data->sg_len;

	host->offset = 0;
	host->remain = host->cur_sg->length;
}

static inline int wbsd_next_sg(struct wbsd_host *host)
{
	/*
	 * Skip to next SG entry.
	 */
	host->cur_sg++;
	host->num_sg--;

	/*
	 * Any entries left?
	 */
	if (host->num_sg > 0) {
		host->offset = 0;
		host->remain = host->cur_sg->length;
	}

	return host->num_sg;
}

static inline char *wbsd_kmap_sg(struct wbsd_host *host)
{
	host->mapped_sg = kmap_atomic(host->cur_sg->page, KM_BIO_SRC_IRQ) +
		host->cur_sg->offset;
	return host->mapped_sg;
}

static inline void wbsd_kunmap_sg(struct wbsd_host *host)
{
	kunmap_atomic(host->mapped_sg, KM_BIO_SRC_IRQ);
}

static inline void wbsd_sg_to_dma(struct wbsd_host *host, struct mmc_data *data)
{
	unsigned int len, i, size;
	struct scatterlist *sg;
	char *dmabuf = host->dma_buffer;
	char *sgbuf;

	size = host->size;

	sg = data->sg;
	len = data->sg_len;

	/*
	 * Just loop through all entries. Size might not
	 * be the entire list though so make sure that
	 * we do not transfer too much.
	 */
	for (i = 0; i < len; i++) {
		sgbuf = kmap_atomic(sg[i].page, KM_BIO_SRC_IRQ) + sg[i].offset;
		if (size < sg[i].length)
			memcpy(dmabuf, sgbuf, size);
		else
			memcpy(dmabuf, sgbuf, sg[i].length);
		kunmap_atomic(sgbuf, KM_BIO_SRC_IRQ);
		dmabuf += sg[i].length;

		if (size < sg[i].length)
			size = 0;
		else
			size -= sg[i].length;

		if (size == 0)
			break;
	}

	/*
	 * Check that we didn't get a request to transfer
	 * more data than can fit into the SG list.
	 */

	BUG_ON(size != 0);

	host->size -= size;
}

static inline void wbsd_dma_to_sg(struct wbsd_host *host, struct mmc_data *data)
{
	unsigned int len, i, size;
	struct scatterlist *sg;
	char *dmabuf = host->dma_buffer;
	char *sgbuf;

	size = host->size;

	sg = data->sg;
	len = data->sg_len;

	/*
	 * Just loop through all entries. Size might not
	 * be the entire list though so make sure that
	 * we do not transfer too much.
	 */
	for (i = 0; i < len; i++) {
		sgbuf = kmap_atomic(sg[i].page, KM_BIO_SRC_IRQ) + sg[i].offset;
		if (size < sg[i].length)
			memcpy(sgbuf, dmabuf, size);
		else
			memcpy(sgbuf, dmabuf, sg[i].length);
		kunmap_atomic(sgbuf, KM_BIO_SRC_IRQ);
		dmabuf += sg[i].length;

		if (size < sg[i].length)
			size = 0;
		else
			size -= sg[i].length;

		if (size == 0)
			break;
	}

	/*
	 * Check that we didn't get a request to transfer
	 * more data than can fit into the SG list.
	 */

	BUG_ON(size != 0);

	host->size -= size;
}

/*
 * Command handling
 */

static inline void wbsd_get_short_reply(struct wbsd_host *host,
					struct mmc_command *cmd)
{
	/*
	 * Correct response type?
	 */
	if (wbsd_read_index(host, WBSD_IDX_RSPLEN) != WBSD_RSP_SHORT) {
		cmd->error = MMC_ERR_INVALID;
		return;
	}

	cmd->resp[0]  = wbsd_read_index(host, WBSD_IDX_RESP12) << 24;
	cmd->resp[0] |= wbsd_read_index(host, WBSD_IDX_RESP13) << 16;
	cmd->resp[0] |= wbsd_read_index(host, WBSD_IDX_RESP14) << 8;
	cmd->resp[0] |= wbsd_read_index(host, WBSD_IDX_RESP15) << 0;
	cmd->resp[1]  = wbsd_read_index(host, WBSD_IDX_RESP16) << 24;
}

static inline void wbsd_get_long_reply(struct wbsd_host *host,
	struct mmc_command *cmd)
{
	int i;

	/*
	 * Correct response type?
	 */
	if (wbsd_read_index(host, WBSD_IDX_RSPLEN) != WBSD_RSP_LONG) {
		cmd->error = MMC_ERR_INVALID;
		return;
	}

	for (i = 0; i < 4; i++) {
		cmd->resp[i] =
			wbsd_read_index(host, WBSD_IDX_RESP1 + i * 4) << 24;
		cmd->resp[i] |=
			wbsd_read_index(host, WBSD_IDX_RESP2 + i * 4) << 16;
		cmd->resp[i] |=
			wbsd_read_index(host, WBSD_IDX_RESP3 + i * 4) << 8;
		cmd->resp[i] |=
			wbsd_read_index(host, WBSD_IDX_RESP4 + i * 4) << 0;
	}
}

static void wbsd_send_command(struct wbsd_host *host, struct mmc_command *cmd)
{
	int i;
	u8 status, isr;

	DBGF("Sending cmd (%x)\n", cmd->opcode);

	/*
	 * Clear accumulated ISR. The interrupt routine
	 * will fill this one with events that occur during
	 * transfer.
	 */
	host->isr = 0;

	/*
	 * Send the command (CRC calculated by host).
	 */
	outb(cmd->opcode, host->base + WBSD_CMDR);
	for (i = 3; i >= 0; i--)
		outb((cmd->arg >> (i * 8)) & 0xff, host->base + WBSD_CMDR);

	cmd->error = MMC_ERR_NONE;

	/*
	 * Wait for the request to complete.
	 */
	do {
		status = wbsd_read_index(host, WBSD_IDX_STATUS);
	} while (status & WBSD_CARDTRAFFIC);

	/*
	 * Do we expect a reply?
	 */
	if (cmd->flags & MMC_RSP_PRESENT) {
		/*
		 * Read back status.
		 */
		isr = host->isr;

		/* Card removed? */
		if (isr & WBSD_INT_CARD)
			cmd->error = MMC_ERR_TIMEOUT;
		/* Timeout? */
		else if (isr & WBSD_INT_TIMEOUT)
			cmd->error = MMC_ERR_TIMEOUT;
		/* CRC? */
		else if ((cmd->flags & MMC_RSP_CRC) && (isr & WBSD_INT_CRC))
			cmd->error = MMC_ERR_BADCRC;
		/* All ok */
		else {
			if (cmd->flags & MMC_RSP_136)
				wbsd_get_long_reply(host, cmd);
			else
				wbsd_get_short_reply(host, cmd);
		}
	}

	DBGF("Sent cmd (%x), res %d\n", cmd->opcode, cmd->error);
}

/*
 * Data functions
 */

static void wbsd_empty_fifo(struct wbsd_host *host)
{
	struct mmc_data *data = host->mrq->cmd->data;
	char *buffer;
	int i, fsr, fifo;

	/*
	 * Handle excessive data.
	 */
	if (data->bytes_xfered == host->size)
		return;

	buffer = wbsd_kmap_sg(host) + host->offset;

	/*
	 * Drain the fifo. This has a tendency to loop longer
	 * than the FIFO length (usually one block).
	 */
	while (!((fsr = inb(host->base + WBSD_FSR)) & WBSD_FIFO_EMPTY)) {
		/*
		 * The size field in the FSR is broken so we have to
		 * do some guessing.
		 */
		if (fsr & WBSD_FIFO_FULL)
			fifo = 16;
		else if (fsr & WBSD_FIFO_FUTHRE)
			fifo = 8;
		else
			fifo = 1;

		for (i = 0; i < fifo; i++) {
			*buffer = inb(host->base + WBSD_DFR);
			buffer++;
			host->offset++;
			host->remain--;

			data->bytes_xfered++;

			/*
			 * Transfer done?
			 */
			if (data->bytes_xfered == host->size) {
				wbsd_kunmap_sg(host);
				return;
			}

			/*
			 * End of scatter list entry?
			 */
			if (host->remain == 0) {
				wbsd_kunmap_sg(host);

				/*
				 * Get next entry. Check if last.
				 */
				if (!wbsd_next_sg(host)) {
					/*
					 * We should never reach this point.
					 * It means that we're trying to
					 * transfer more blocks than can fit
					 * into the scatter list.
					 */
					BUG_ON(1);

					host->size = data->bytes_xfered;

					return;
				}

				buffer = wbsd_kmap_sg(host);
			}
		}
	}

	wbsd_kunmap_sg(host);

	/*
	 * This is a very dirty hack to solve a
	 * hardware problem. The chip doesn't trigger
	 * FIFO threshold interrupts properly.
	 */
	if ((host->size - data->bytes_xfered) < 16)
		tasklet_schedule(&host->fifo_tasklet);
}

static void wbsd_fill_fifo(struct wbsd_host *host)
{
	struct mmc_data *data = host->mrq->cmd->data;
	char *buffer;
	int i, fsr, fifo;

	/*
	 * Check that we aren't being called after the
	 * entire buffer has been transfered.
	 */
	if (data->bytes_xfered == host->size)
		return;

	buffer = wbsd_kmap_sg(host) + host->offset;

	/*
	 * Fill the fifo. This has a tendency to loop longer
	 * than the FIFO length (usually one block).
	 */
	while (!((fsr = inb(host->base + WBSD_FSR)) & WBSD_FIFO_FULL)) {
		/*
		 * The size field in the FSR is broken so we have to
		 * do some guessing.
		 */
		if (fsr & WBSD_FIFO_EMPTY)
			fifo = 0;
		else if (fsr & WBSD_FIFO_EMTHRE)
			fifo = 8;
		else
			fifo = 15;

		for (i = 16; i > fifo; i--) {
			outb(*buffer, host->base + WBSD_DFR);
			buffer++;
			host->offset++;
			host->remain--;

			data->bytes_xfered++;

			/*
			 * Transfer done?
			 */
			if (data->bytes_xfered == host->size) {
				wbsd_kunmap_sg(host);
				return;
			}

			/*
			 * End of scatter list entry?
			 */
			if (host->remain == 0) {
				wbsd_kunmap_sg(host);

				/*
				 * Get next entry. Check if last.
				 */
				if (!wbsd_next_sg(host)) {
					/*
					 * We should never reach this point.
					 * It means that we're trying to
					 * transfer more blocks than can fit
					 * into the scatter list.
					 */
					BUG_ON(1);

					host->size = data->bytes_xfered;

					return;
				}

				buffer = wbsd_kmap_sg(host);
			}
		}
	}

	wbsd_kunmap_sg(host);

	/*
	 * The controller stops sending interrupts for
	 * 'FIFO empty' under certain conditions. So we
	 * need to be a bit more pro-active.
	 */
	tasklet_schedule(&host->fifo_tasklet);
}

static void wbsd_prepare_data(struct wbsd_host *host, struct mmc_data *data)
{
	u16 blksize;
	u8 setup;
	unsigned long dmaflags;

	DBGF("blksz %04x blks %04x flags %08x\n",
		data->blksz, data->blocks, data->flags);
	DBGF("tsac %d ms nsac %d clk\n",
		data->timeout_ns / 1000000, data->timeout_clks);

	/*
	 * Calculate size.
	 */
	host->size = data->blocks * data->blksz;

	/*
	 * Check timeout values for overflow.
	 * (Yes, some cards cause this value to overflow).
	 */
	if (data->timeout_ns > 127000000)
		wbsd_write_index(host, WBSD_IDX_TAAC, 127);
	else {
		wbsd_write_index(host, WBSD_IDX_TAAC,
			data->timeout_ns / 1000000);
	}

	if (data->timeout_clks > 255)
		wbsd_write_index(host, WBSD_IDX_NSAC, 255);
	else
		wbsd_write_index(host, WBSD_IDX_NSAC, data->timeout_clks);

	/*
	 * Inform the chip of how large blocks will be
	 * sent. It needs this to determine when to
	 * calculate CRC.
	 *
	 * Space for CRC must be included in the size.
	 * Two bytes are needed for each data line.
	 */
	if (host->bus_width == MMC_BUS_WIDTH_1) {
		blksize = data->blksz + 2;

		wbsd_write_index(host, WBSD_IDX_PBSMSB, (blksize >> 4) & 0xF0);
		wbsd_write_index(host, WBSD_IDX_PBSLSB, blksize & 0xFF);
	} else if (host->bus_width == MMC_BUS_WIDTH_4) {
		blksize = data->blksz + 2 * 4;

		wbsd_write_index(host, WBSD_IDX_PBSMSB,
			((blksize >> 4) & 0xF0) | WBSD_DATA_WIDTH);
		wbsd_write_index(host, WBSD_IDX_PBSLSB, blksize & 0xFF);
	} else {
		data->error = MMC_ERR_INVALID;
		return;
	}

	/*
	 * Clear the FIFO. This is needed even for DMA
	 * transfers since the chip still uses the FIFO