wbsd.c

来自「linux 内核源代码」· C语言 代码 · 共 2,048 行 · 第 1/3 页

	 * Send a stop command if needed.
	 */
	if (data->stop)
		wbsd_send_command(host, data->stop);

	/*
	 * Wait for the controller to leave data
	 * transfer state.
	 */
	do {
		status = wbsd_read_index(host, WBSD_IDX_STATUS);
	} while (status & (WBSD_BLOCK_READ | WBSD_BLOCK_WRITE));

	/*
	 * DMA transfer?
	 */
	if (host->dma >= 0) {
		/*
		 * Disable DMA on the host.
		 */
		wbsd_write_index(host, WBSD_IDX_DMA, 0);

		/*
		 * Turn of ISA DMA controller.
		 */
		dmaflags = claim_dma_lock();
		disable_dma(host->dma);
		clear_dma_ff(host->dma);
		count = get_dma_residue(host->dma);
		release_dma_lock(dmaflags);

		data->bytes_xfered = host->mrq->data->blocks *
			host->mrq->data->blksz - count;
		data->bytes_xfered -= data->bytes_xfered % data->blksz;

		/*
		 * Any leftover data?
		 */
		if (count) {
			printk(KERN_ERR "%s: Incomplete DMA transfer. "
				"%d bytes left.\n",
				mmc_hostname(host->mmc), count);

			if (!data->error)
				data->error = -EIO;
		} else {
			/*
			 * Transfer data from DMA buffer to
			 * SG list.
			 */
			if (data->flags & MMC_DATA_READ)
				wbsd_dma_to_sg(host, data);
		}

		if (data->error) {
			if (data->bytes_xfered)
				data->bytes_xfered -= data->blksz;
		}
	}

	wbsd_request_end(host, host->mrq);
}

/*****************************************************************************\
 *                                                                           *
 * MMC layer callbacks                                                       *
 *                                                                           *
\*****************************************************************************/

static void wbsd_request(struct mmc_host *mmc, struct mmc_request *mrq)
{
	struct wbsd_host *host = mmc_priv(mmc);
	struct mmc_command *cmd;

	/*
	 * Disable tasklets to avoid a deadlock.
	 */
	spin_lock_bh(&host->lock);

	BUG_ON(host->mrq != NULL);

	cmd = mrq->cmd;

	host->mrq = mrq;

	/*
	 * Check that there is actually a card in the slot.
	 */
	if (!(host->flags & WBSD_FCARD_PRESENT)) {
		cmd->error = -ENOMEDIUM;
		goto done;
	}

	if (cmd->data) {
		/*
		 * The hardware is so delightfully stupid that it has a list
		 * of "data" commands. If a command isn't on this list, it'll
		 * just go back to the idle state and won't send any data
		 * interrupts.
		 */
		switch (cmd->opcode) {
		case 11:
		case 17:
		case 18:
		case 20:
		case 24:
		case 25:
		case 26:
		case 27:
		case 30:
		case 42:
		case 56:
			break;

		/* ACMDs. We don't keep track of state, so we just treat them
		 * like any other command. */
		case 51:
			break;

		default:
#ifdef CONFIG_MMC_DEBUG
			printk(KERN_WARNING "%s: Data command %d is not "
				"supported by this controller.\n",
				mmc_hostname(host->mmc), cmd->opcode);
#endif
			cmd->error = -EINVAL;

			goto done;
		};
	}

	/*
	 * Does the request include data?
	 */
	if (cmd->data) {
		wbsd_prepare_data(host, cmd->data);

		if (cmd->data->error)
			goto done;
	}

	wbsd_send_command(host, cmd);

	/*
	 * If this is a data transfer the request
	 * will be finished after the data has
	 * transfered.
	 */
	if (cmd->data && !cmd->error) {
		/*
		 * Dirty fix for hardware bug.
		 */
		if (host->dma == -1)
			tasklet_schedule(&host->fifo_tasklet);

		spin_unlock_bh(&host->lock);

		return;
	}

done:
	wbsd_request_end(host, mrq);

	spin_unlock_bh(&host->lock);
}

static void wbsd_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
{
	struct wbsd_host *host = mmc_priv(mmc);
	u8 clk, setup, pwr;

	spin_lock_bh(&host->lock);

	/*
	 * Reset the chip on each power off.
	 * Should clear out any weird states.
	 */
	if (ios->power_mode == MMC_POWER_OFF)
		wbsd_init_device(host);

	if (ios->clock >= 24000000)
		clk = WBSD_CLK_24M;
	else if (ios->clock >= 16000000)
		clk = WBSD_CLK_16M;
	else if (ios->clock >= 12000000)
		clk = WBSD_CLK_12M;
	else
		clk = WBSD_CLK_375K;

	/*
	 * Only write to the clock register when
	 * there is an actual change.
	 */
	if (clk != host->clk) {
		wbsd_write_index(host, WBSD_IDX_CLK, clk);
		host->clk = clk;
	}

	/*
	 * Power up card.
	 */
	if (ios->power_mode != MMC_POWER_OFF) {
		pwr = inb(host->base + WBSD_CSR);
		pwr &= ~WBSD_POWER_N;
		outb(pwr, host->base + WBSD_CSR);
	}

	/*
	 * MMC cards need to have pin 1 high during init.
	 * It wreaks havoc with the card detection though so
	 * that needs to be disabled.
	 */
	setup = wbsd_read_index(host, WBSD_IDX_SETUP);
	if (ios->chip_select == MMC_CS_HIGH) {
		BUG_ON(ios->bus_width != MMC_BUS_WIDTH_1);
		setup |= WBSD_DAT3_H;
		host->flags |= WBSD_FIGNORE_DETECT;
	} else {
		if (setup & WBSD_DAT3_H) {
			setup &= ~WBSD_DAT3_H;

			/*
			 * We cannot resume card detection immediatly
			 * because of capacitance and delays in the chip.
			 */
			mod_timer(&host->ignore_timer, jiffies + HZ / 100);
		}
	}
	wbsd_write_index(host, WBSD_IDX_SETUP, setup);

	/*
	 * Store bus width for later. Will be used when
	 * setting up the data transfer.
	 */
	host->bus_width = ios->bus_width;

	spin_unlock_bh(&host->lock);
}

static int wbsd_get_ro(struct mmc_host *mmc)
{
	struct wbsd_host *host = mmc_priv(mmc);
	u8 csr;

	spin_lock_bh(&host->lock);

	csr = inb(host->base + WBSD_CSR);
	csr |= WBSD_MSLED;
	outb(csr, host->base + WBSD_CSR);

	mdelay(1);

	csr = inb(host->base + WBSD_CSR);
	csr &= ~WBSD_MSLED;
	outb(csr, host->base + WBSD_CSR);

	spin_unlock_bh(&host->lock);

	return csr & WBSD_WRPT;
}

static const struct mmc_host_ops wbsd_ops = {
	.request	= wbsd_request,
	.set_ios	= wbsd_set_ios,
	.get_ro		= wbsd_get_ro,
};

/*****************************************************************************\
 *                                                                           *
 * Interrupt handling                                                        *
 *                                                                           *
\*****************************************************************************/

/*
 * Helper function to reset detection ignore
 */

static void wbsd_reset_ignore(unsigned long data)
{
	struct wbsd_host *host = (struct wbsd_host *)data;

	BUG_ON(host == NULL);

	DBG("Resetting card detection ignore\n");

	spin_lock_bh(&host->lock);

	host->flags &= ~WBSD_FIGNORE_DETECT;

	/*
	 * Card status might have changed during the
	 * blackout.
	 */
	tasklet_schedule(&host->card_tasklet);

	spin_unlock_bh(&host->lock);
}

/*
 * Tasklets
 */

static inline struct mmc_data *wbsd_get_data(struct wbsd_host *host)
{
	WARN_ON(!host->mrq);
	if (!host->mrq)
		return NULL;

	WARN_ON(!host->mrq->cmd);
	if (!host->mrq->cmd)
		return NULL;

	WARN_ON(!host->mrq->cmd->data);
	if (!host->mrq->cmd->data)
		return NULL;

	return host->mrq->cmd->data;
}

static void wbsd_tasklet_card(unsigned long param)
{
	struct wbsd_host *host = (struct wbsd_host *)param;
	u8 csr;
	int delay = -1;

	spin_lock(&host->lock);

	if (host->flags & WBSD_FIGNORE_DETECT) {
		spin_unlock(&host->lock);
		return;
	}

	csr = inb(host->base + WBSD_CSR);
	WARN_ON(csr == 0xff);

	if (csr & WBSD_CARDPRESENT) {
		if (!(host->flags & WBSD_FCARD_PRESENT)) {
			DBG("Card inserted\n");
			host->flags |= WBSD_FCARD_PRESENT;

			delay = 500;
		}
	} else if (host->flags & WBSD_FCARD_PRESENT) {
		DBG("Card removed\n");
		host->flags &= ~WBSD_FCARD_PRESENT;

		if (host->mrq) {
			printk(KERN_ERR "%s: Card removed during transfer!\n",
				mmc_hostname(host->mmc));
			wbsd_reset(host);

			host->mrq->cmd->error = -ENOMEDIUM;
			tasklet_schedule(&host->finish_tasklet);
		}

		delay = 0;
	}

	/*
	 * Unlock first since we might get a call back.
	 */

	spin_unlock(&host->lock);

	if (delay != -1)
		mmc_detect_change(host->mmc, msecs_to_jiffies(delay));
}

static void wbsd_tasklet_fifo(unsigned long param)
{
	struct wbsd_host *host = (struct wbsd_host *)param;
	struct mmc_data *data;

	spin_lock(&host->lock);

	if (!host->mrq)
		goto end;

	data = wbsd_get_data(host);
	if (!data)
		goto end;

	if (data->flags & MMC_DATA_WRITE)
		wbsd_fill_fifo(host);
	else
		wbsd_empty_fifo(host);

	/*
	 * Done?
	 */
	if (host->num_sg == 0) {
		wbsd_write_index(host, WBSD_IDX_FIFOEN, 0);
		tasklet_schedule(&host->finish_tasklet);
	}

end:
	spin_unlock(&host->lock);
}

static void wbsd_tasklet_crc(unsigned long param)
{
	struct wbsd_host *host = (struct wbsd_host *)param;
	struct mmc_data *data;

	spin_lock(&host->lock);

	if (!host->mrq)
		goto end;

	data = wbsd_get_data(host);
	if (!data)
		goto end;

	DBGF("CRC error\n");

	data->error = -EILSEQ;

	tasklet_schedule(&host->finish_tasklet);

end:
	spin_unlock(&host->lock);
}

static void wbsd_tasklet_timeout(unsigned long param)
{
	struct wbsd_host *host = (struct wbsd_host *)param;
	struct mmc_data *data;

	spin_lock(&host->lock);

	if (!host->mrq)
		goto end;

	data = wbsd_get_data(host);
	if (!data)
		goto end;

	DBGF("Timeout\n");

	data->error = -ETIMEDOUT;

	tasklet_schedule(&host->finish_tasklet);

end:
	spin_unlock(&host->lock);
}

static void wbsd_tasklet_finish(unsigned long param)
{
	struct wbsd_host *host = (struct wbsd_host *)param;
	struct mmc_data *data;

	spin_lock(&host->lock);

	WARN_ON(!host->mrq);
	if (!host->mrq)
		goto end;

	data = wbsd_get_data(host);
	if (!data)
		goto end;

	wbsd_finish_data(host, data);

end:
	spin_unlock(&host->lock);
}

/*
 * Interrupt handling
 */

static irqreturn_t wbsd_irq(int irq, void *dev_id)
{
	struct wbsd_host *host = dev_id;
	int isr;

	isr = inb(host->base + WBSD_ISR);

	/*
	 * Was it actually our hardware that caused the interrupt?
	 */
	if (isr == 0xff || isr == 0x00)
		return IRQ_NONE;

	host->isr |= isr;

	/*
	 * Schedule tasklets as needed.
	 */
	if (isr & WBSD_INT_CARD)
		tasklet_schedule(&host->card_tasklet);
	if (isr & WBSD_INT_FIFO_THRE)
		tasklet_schedule(&host->fifo_tasklet);
	if (isr & WBSD_INT_CRC)
		tasklet_hi_schedule(&host->crc_tasklet);
	if (isr & WBSD_INT_TIMEOUT)
		tasklet_hi_schedule(&host->timeout_tasklet);
	if (isr & WBSD_INT_TC)
		tasklet_schedule(&host->finish_tasklet);

	return IRQ_HANDLED;
}

/*****************************************************************************\
 *                                                                           *
 * Device initialisation and shutdown                                        *
 *                                                                           *
\*****************************************************************************/

/*
 * Allocate/free MMC structure.
 */

static int __devinit wbsd_alloc_mmc(struct device *dev)
{
	struct mmc_host *mmc;
	struct wbsd_host *host;

	/*
	 * Allocate MMC structure.
	 */
	mmc = mmc_alloc_host(sizeof(struct wbsd_host), dev);
	if (!mmc)
		return -ENOMEM;

	host = mmc_priv(mmc);
	host->mmc = mmc;

	host->dma = -1;

	/*
	 * Set host parameters.
	 */
	mmc->ops = &wbsd_ops;
	mmc->f_min = 375000;
	mmc->f_max = 24000000;
	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
	mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_MULTIWRITE;

	spin_lock_init(&host->lock);

	/*
	 * Set up timers
	 */
	init_timer(&host->ignore_timer);
	host->ignore_timer.data = (unsigned long)host;
	host->ignore_timer.function = wbsd_reset_ignore;

	/*
	 * Maximum number of segments. Worst case is one sector per segment
	 * so this will be 64kB/512.
	 */
	mmc->max_hw_segs = 128;
	mmc->max_phys_segs = 128;

	/*
	 * Maximum request size. Also limited by 64KiB buffer.
	 */
	mmc->max_req_size = 65536;

	/*
	 * Maximum segment size. Could be one segment with the maximum number
	 * of bytes.
	 */
	mmc->max_seg_size = mmc->max_req_size;

	/*
	 * Maximum block size. We have 12 bits (= 4095) but have to subtract
	 * space for CRC. So the maximum is 4095 - 4*2 = 4087.
	 */
	mmc->max_blk_size = 4087;

	/*
	 * Maximum block count. There is no real limit so the maximum
	 * request size will be the only restriction.
	 */
	mmc->max_blk_count = mmc->max_req_size;

	dev_set_drvdata(dev, mmc);

	return 0;
}

static void wbsd_free_mmc(struct device *dev)
{
	struct mmc_host *mmc;
	struct wbsd_host *host;

	mmc = dev_get_drvdata(dev);
	if (!mmc)
		return;

	host = mmc_priv(mmc);
	BUG_ON(host == NULL);

	del_timer_sync(&host->ignore_timer);

	mmc_free_host(mmc);

	dev_set_drvdata(dev, NULL);
}

/*
 * Scan for known chip id:s
 */

static int __devinit wbsd_scan(struct wbsd_host *host)
{
	int i, j, k;
	int id;

	/*
	 * Iterate through all ports, all codes to
	 * find hardware that is in our known list.
	 */
	for (i = 0; i < ARRAY_SIZE(config_ports); i++) {
		if (!request_region(config_ports[i], 2, DRIVER_NAME))
			continue;

		for (j = 0; j < ARRAY_SIZE(unlock_codes); j++) {
			id = 0xFFFF;

			host->config = config_ports[i];
			host->unlock_code = unlock_codes[j];

			wbsd_unlock_config(host);

			outb(WBSD_CONF_ID_HI, config_ports[i]);
			id = inb(config_ports[i] + 1) << 8;

			outb(WBSD_CONF_ID_LO, config_ports[i]);
			id |= inb(config_ports[i] + 1);

			wbsd_lock_config(host);

			for (k = 0; k < ARRAY_SIZE(valid_ids); k++) {
				if (id == valid_ids[k]) {
					host->chip_id = id;

					return 0;
				}
			}

			if (id != 0xFFFF) {
				DBG("Unknown hardware (id %x) found at %x\n",
					id, config_ports[i]);
			}
		}

		release_region(config_ports[i], 2);
	}

	host->config = 0;
	host->unlock_code = 0;

	return -ENODEV;
}

/*
 * Allocate/free io port ranges
 */

static int __devinit wbsd_request_region(struct wbsd_host *host, int base)
{
	if (base & 0x7)
		return -EINVAL;

	if (!request_region(base, 8, DRIVER_NAME))
		return -EIO;

	host->base = base;

	return 0;
}

static void wbsd_release_regions(struct wbsd_host *host)
{
	if (host->base)
		release_region(host->base, 8);

	host->base = 0;