lkml.org 
[lkml]   [2006]   [Feb]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC] mmc: add OMAP driver
On Fri, Feb 24, 2006 at 12:38:24PM -0400, Carlos Aguiar wrote:
> All suggestions and comments are welcome.

Okay, further comments. Almost there!

> +/* PIO only */
> +static void
> +mmc_omap_xfer_data(struct mmc_omap_host *host, int write)
> +{
> + int n;
> + void __iomem *reg;
> + u16 *p;
> +
> + if (host->buffer_bytes_left == 0) {
> + host->sg_idx++;
> + BUG_ON(host->sg_idx == host->sg_len);
> + mmc_omap_sg_to_buf(host);
> + }
> + n = 64;
> + if (n > host->buffer_bytes_left)
> + n = host->buffer_bytes_left;
> + host->buffer_bytes_left -= n;
> + host->total_bytes_left -= n;
> + host->data->bytes_xfered += n;
> +
> + /* Optimize the loop a bit by calculating the register only
> + * once */
> + reg = host->base + OMAP_MMC_REG_DATA;
> + p = host->buffer;
> + n /= 2;
> + if (write) {
> + while (n--)
> + __raw_writew(*p++, reg);
> + } else {
> + while (n-- > 0)
> + *p++ = __raw_readw(reg);
> + }

I thought I made a comment about readsw/writesw being more efficient
versions of these?

> + host->buffer = p;
> +}

> +static irqreturn_t mmc_omap_irq(int irq, void *dev_id, struct pt_regs *regs)
> +{
> + struct mmc_omap_host * host = (struct mmc_omap_host *)dev_id;
> + u16 status;
> + int end_command;
> + int end_transfer;
> + int transfer_error;
> +
> + if (host->cmd == NULL && host->data == NULL) {
> + status = OMAP_MMC_READ(host->base, STAT);
> + printk(KERN_INFO "MMC%d: Spurious interrupt 0x%04x\n",
> + host->id, status);

dev_info(mmc_dev(host->mmc), "spurious irq 0x%04x\n", status);

There's no need to print host->id - mmc_dev(host->mmc) will print the
platform device bus_id, which is generated from the platform device
name and the platform device id.

> + if (status != 0) {
> + OMAP_MMC_WRITE(host->base, STAT, status);
> + OMAP_MMC_WRITE(host->base, IE, 0);
> + }
> + return IRQ_HANDLED;
> + }
> +
> + end_command = 0;
> + end_transfer = 0;
> + transfer_error = 0;
> +
> + while ((status = OMAP_MMC_READ(host->base, STAT)) != 0) {
> + OMAP_MMC_WRITE(host->base, STAT, status);
> +#ifdef CONFIG_MMC_DEBUG
> + printk(KERN_DEBUG "MMC IRQ %04x (CMD %d): ", status,
> + host->cmd != NULL ? host->cmd->opcode : -1);

dev_dbg(mmc_dev(host->mmc), "MMC IRQ %04x (CMD %d): ",
status, host->cmd != NULL ? host->cmd->opcode : -1);

> + mmc_omap_report_irq(status);
> + printk("\n");
> +#endif
> + if (host->total_bytes_left) {
> + if ((status & OMAP_MMC_STAT_A_FULL) ||
> + (status & OMAP_MMC_STAT_END_OF_DATA))
> + mmc_omap_xfer_data(host, 0);
> + if (status & OMAP_MMC_STAT_A_EMPTY)
> + mmc_omap_xfer_data(host, 1);
> + }
> +
> + if (status & OMAP_MMC_STAT_END_OF_DATA) {
> + end_transfer = 1;
> + }
> +
> + if (status & OMAP_MMC_STAT_DATA_TOUT) {
> + dev_dbg(mmc_dev(host->mmc), "MMC%d: Data timeout\n",
> + host->id);

dev_dbg(mmc_dev(host->mmc), "data timeout\n");

> + if (host->data) {
> + host->data->error |= MMC_ERR_TIMEOUT;
> + transfer_error = 1;
> + }
> + }
> +
> + if (status & OMAP_MMC_STAT_DATA_CRC) {
> + if (host->data) {
> + host->data->error |= MMC_ERR_BADCRC;
> + dev_dbg(mmc_dev(host->mmc), "MMC%d: Data CRC
> + error, bytes left %d\n",
> + host->id,
> + host->total_bytes_left);

dev_dbg(mmc_dev(host->mmc),
"data CRC error, bytes left %d\n",
host->total_bytes_left);

> + transfer_error = 1;
> + } else {
> + dev_dbg(mmc_dev(host->mmc), "MMC%d: Data CRC
> + error\n", host->id);

dev_dbg(mmc_dev(host->mmc), "data CRC error\n");

> + }
> + }
> +
> + if (status & OMAP_MMC_STAT_CMD_TOUT) {
> + /* Timeouts are routine with some commands */
> + if (host->cmd) {
> + if (host->cmd->opcode != MMC_ALL_SEND_CID &&
> + host->cmd->opcode !=
> + MMC_SEND_OP_COND &&
> + host->cmd->opcode !=
> + MMC_APP_CMD &&
> + !mmc_omap_cover_is_open(host))
> + dev_err(mmc_dev(host->mmc), "MMC%d:
> + Command timeout,
> + CMD%d\n", host->id,
> + host->cmd->opcode);

dev_err(mmc_dev(host->mmc),
"command timeout, CMD %d\n",
host->cmd->opcode);

> + host->cmd->error = MMC_ERR_TIMEOUT;
> + end_command = 1;
> + }
> + }
> +
> + if (status & OMAP_MMC_STAT_CMD_CRC) {
> + if (host->cmd) {
> + dev_err(mmc_dev(host->mmc), "MMC%d: Command CRC
> + error (CMD%d, arg 0x%08x)\n",
> + host->id, host->cmd->opcode,
> + host->cmd->arg);

dev_err(mmc_dev(host->mmc),
"command CRC error (CMD%d, arg 0x%08x)\n",
host->cmd->opcode, host->cmd->arg);

> + host->cmd->error = MMC_ERR_BADCRC;
> + end_command = 1;
> + } else
> + dev_err(mmc_dev(host->mmc), "MMC%d: Command CRC
> + error without cmd?\n",
> + host->id);

dev_err(mmc_dev(host->mmc),
"command CRC error without cmd?\n");

> + }
> +
> + if (status & OMAP_MMC_STAT_CARD_ERR) {
> + if (host->cmd && host->cmd->opcode == MMC_STOP_TRANSMISSION) {
> + u32 response = OMAP_MMC_READ(host->base, RSP6)
> + | (OMAP_MMC_READ(host->base, RSP7) << 16);
> + /* STOP sometimes sets must-ignore bits */
> + if (!(response & (R1_CC_ERROR
> + | R1_ILLEGAL_COMMAND
> + | R1_COM_CRC_ERROR))) {
> + end_command = 1;
> + continue;
> + }
> + }
> +
> + dev_dbg(mmc_dev(host->mmc), "MMC%d: Card status error (CMD%d)\n",
> + host->id, host->cmd->opcode);

dev_dbg(mmc_dev(host->mmc), "card status error (CMD%d)\n",
host->cmd->opcode);

> + if (host->cmd) {
> + host->cmd->error = MMC_ERR_FAILED;
> + end_command = 1;
> + }
> + if (host->data) {
> + host->data->error = MMC_ERR_FAILED;
> + transfer_error = 1;
> + }
> + }
> +
> + /*
> + * NOTE: On 1610 the END_OF_CMD may come too early when
> + * starting a write
> + */
> + if ((status & OMAP_MMC_STAT_END_OF_CMD) &&
> + (!(status & OMAP_MMC_STAT_A_EMPTY))) {
> + end_command = 1;
> + }
> + }
> +
> + if (end_command) {
> + mmc_omap_cmd_done(host, host->cmd);
> + }
> + if (transfer_error)
> + mmc_omap_xfer_done(host, host->data);
> + else if (end_transfer)
> + mmc_omap_end_of_data(host, host->data);
> +
> + return IRQ_HANDLED;
> +}

Same comments for the other dev_* and printk's.

> +static int __init mmc_omap_probe(struct platform_device *pdev)
> +{
> + struct omap_mmc_conf *minfo = pdev->dev.platform_data;
> + struct mmc_host *mmc;
> + struct mmc_omap_host *host = NULL;
> + int ret = 0;
> +
> + if (platform_get_resource(pdev, IORESOURCE_MEM, 0) ||
> + platform_get_irq(pdev, IORESOURCE_IRQ, 0)) {
> + dev_err(&pdev->dev, "mmc_omap_probe: invalid resource type\n");
> + return -ENODEV;
> + }
> +
> + if (!request_mem_region(pdev->resource[0].start,
> + pdev->resource[0].end - pdev->resource[0].start + 1,
> + pdev->name)) {
> + dev_dbg(&pdev->dev, "request_mem_region failed\n");
> + return -EBUSY;
> + }
> +
> + mmc = mmc_alloc_host(sizeof(struct mmc_omap_host), &pdev->dev);
> + if (!mmc) {
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + host = mmc_priv(mmc);
> + host->mmc = mmc;
> +
> + spin_lock_init(&host->dma_lock);
> + init_timer(&host->dma_timer);
> + host->dma_timer.function = mmc_omap_dma_timer;
> + host->dma_timer.data = (unsigned long) host;
> +
> + host->id = pdev->id;
> +
> + if (cpu_is_omap24xx()) {
> + host->iclk = clk_get(&pdev->dev, "mmc_ick");
> + if (IS_ERR(host->iclk))
> + goto out;
> + clk_enable(host->iclk);
> + }
> +
> + if (!cpu_is_omap24xx())
> + host->fclk = clk_get(&pdev->dev, "mmc_ck");
> + else
> + host->fclk = clk_get(&pdev->dev, "mmc_fck");
> +
> + if (IS_ERR(host->fclk)) {
> + ret = PTR_ERR(host->fclk);
> + goto out;
> + }
> +
> + /* REVISIT:
> + * Also, use minfo->cover to decide how to manage
> + * the card detect sensing.
> + */
> + host->power_pin = minfo->power_pin;
> + host->switch_pin = minfo->switch_pin;
> + host->wp_pin = minfo->wp_pin;
> + host->use_dma = 1;
> + host->dma_ch = -1;
> +
> + host->irq = pdev->resource[1].start;
> + host->base = ioremap(pdev->res.start, SZ_4K);

What if ioremap fails with NULL?

> +
> + if (minfo->wire4)
> + mmc->caps |= MMC_CAP_4_BIT_DATA;
> +
> + mmc->ops = &mmc_omap_ops;
> + mmc->f_min = 400000;
> + mmc->f_max = 24000000;
> + mmc->ocr_avail = MMC_VDD_33_34;

Some cards want at least two bits set - use MMC_VDD_32_33|MMC_VDD_33_34
here please.

--
Russell King
Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/
maintainer of: 2.6 Serial core
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2006-02-24 21:52    [from the cache]
©2003-2011 Jasper Spaans