Commit d380443c authored Jun 13, 2012 by Subhash Jadavani Committed by Chris Ball Jun 26, 2012

mmc: block: fix the data timeout issue with ACMD22



If multi block write operation fails for SD card, during
error handling we send the SD_APP_SEND_NUM_WR_BLKS (ACMD22)
to know how many blocks were already programmed by card.

But mmc_sd_num_wr_blocks() function which sends the ACMD22
calculates the data timeout value from csd.tacc_ns and
csd.tacc_clks parameters which will be 0 for block addressed
(>2GB cards) SD card. This would result in timeout_ns and
timeout_clks being 0 in the mmc_request passed to host driver.
This means host controller would program its data timeout timer
value with 0 which could result in DATA TIMEOUT errors from
controller.

To fix this issue, mmc_sd_num_wr_blocks() should instead
just call the mmc_set_data_timeout() to calculate the
data timeout value. mmc_set_data_timeout() function
ensures that non zero timeout value is set even for
block addressed SD cards.

Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Reviewed-by: Venkatraman S <svenkatr@ti.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

parent d1346a6c

drivers/mmc/card/block.c

+1 −13

Original line number	Diff line number	Diff line
		@@ -554,7 +554,6 @@ static u32 mmc_sd_num_wr_blocks(struct mmc_card *card)
		struct mmc_request mrq = {NULL};
		struct mmc_command cmd = {0};
		struct mmc_data data = {0};
		unsigned int timeout_us;

		struct scatterlist sg;

		@@ -574,23 +573,12 @@ static u32 mmc_sd_num_wr_blocks(struct mmc_card *card)
		cmd.arg = 0;
		cmd.flags = MMC_RSP_SPI_R1 \| MMC_RSP_R1 \| MMC_CMD_ADTC;

		data.timeout_ns = card->csd.tacc_ns * 100;
		data.timeout_clks = card->csd.tacc_clks * 100;

		timeout_us = data.timeout_ns / 1000;
		timeout_us += data.timeout_clks * 1000 /
		(card->host->ios.clock / 1000);

		if (timeout_us > 100000) {
		data.timeout_ns = 100000000;
		data.timeout_clks = 0;
		}

		data.blksz = 4;
		data.blocks = 1;
		data.flags = MMC_DATA_READ;
		data.sg = &sg;
		data.sg_len = 1;
		mmc_set_data_timeout(&data, card);

		mrq.cmd = &cmd;
		mrq.data = &data;

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