Commit 22113efd authored by Aries Lee's avatar Aries Lee Committed by Chris Ball
Browse files

mmc: Test bus-width for old MMC devices 



Some old MMC devices fail with the 4/8 bits the driver tries to use
exclusively.  This patch adds a test for the given bus setup and falls
back to the lower bit mode (until 1-bit mode) when the test fails.

[Major rework and refactoring by tiwai]
[Quirk addition and many fixes by prakity]

Signed-off-by: default avatarAries Lee <arieslee@jmicron.com>
Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
Signed-off-by: default avatarPhilip Rakity <prakity@marvell.com>
Tested-by: default avatarPhilip Rakity <prakity@marvell.com>
Signed-off-by: default avatarChris Ball <cjb@laptop.org>
parent e6f29a8d

drivers/mmc/core/mmc.c

+47 −29
Original line number Diff line number Diff line
@@ -534,39 +534,57 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, 
	 */

	if ((card->csd.mmca_vsn >= CSD_SPEC_VER_4) &&

	    (host->caps & (MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA))) {

		unsigned ext_csd_bit, bus_width;

		static unsigned ext_csd_bits[][2] = {

			{ EXT_CSD_BUS_WIDTH_8, EXT_CSD_DDR_BUS_WIDTH_8 },

			{ EXT_CSD_BUS_WIDTH_4, EXT_CSD_DDR_BUS_WIDTH_4 },

			{ EXT_CSD_BUS_WIDTH_1, EXT_CSD_BUS_WIDTH_1 },

		};

		static unsigned bus_widths[] = {

			MMC_BUS_WIDTH_8,

			MMC_BUS_WIDTH_4,

			MMC_BUS_WIDTH_1

		};

		unsigned idx, bus_width = 0;



		if (host->caps & MMC_CAP_8_BIT_DATA) {

			if (ddr)

				ext_csd_bit = EXT_CSD_DDR_BUS_WIDTH_8;

		if (host->caps & MMC_CAP_8_BIT_DATA)

			idx = 0;

		else

				ext_csd_bit = EXT_CSD_BUS_WIDTH_8;

			bus_width = MMC_BUS_WIDTH_8;

		} else {

			if (ddr)

				ext_csd_bit = EXT_CSD_DDR_BUS_WIDTH_4;

			else

				ext_csd_bit = EXT_CSD_BUS_WIDTH_4;

			bus_width = MMC_BUS_WIDTH_4;

			idx = 1;

		for (; idx < ARRAY_SIZE(bus_widths); idx++) {

			bus_width = bus_widths[idx];

			if (bus_width == MMC_BUS_WIDTH_1)

				ddr = 0; /* no DDR for 1-bit width */

			err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,

					 EXT_CSD_BUS_WIDTH,

					 ext_csd_bits[idx][0]);

			if (!err) {

				/*

				 * If controller can't handle bus width test,

				 * use the highest bus width to maintain

				 * compatibility with previous MMC behavior.

				 */

				if (!(host->caps & MMC_CAP_BUS_WIDTH_TEST))

					break;

				mmc_set_bus_width_ddr(card->host,

						      bus_width, MMC_SDR_MODE);

				err = mmc_bus_test(card, bus_width);

				if (!err)

					break;

			}

		}



		if (!err && ddr) {

			err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,

				 EXT_CSD_BUS_WIDTH, ext_csd_bit);



		if (err && err != -EBADMSG)

			goto free_card;



					EXT_CSD_BUS_WIDTH,

					ext_csd_bits[idx][1]);

		}

		if (err) {

			printk(KERN_WARNING "%s: switch to bus width %d ddr %d "

				"failed\n", mmc_hostname(card->host),

				1 << bus_width, ddr);

			err = 0;

		} else {

			if (ddr)

			goto free_card;

		} else if (ddr) {

			mmc_card_set_ddr_mode(card);

			else

				ddr = MMC_SDR_MODE;



			mmc_set_bus_width_ddr(card->host, bus_width, ddr);

		}

	}

drivers/mmc/core/mmc_ops.c

+101 −0
Original line number Diff line number Diff line
@@ -462,3 +462,104 @@ int mmc_send_status(struct mmc_card *card, u32 *status) 
	return 0;

}



static int

mmc_send_bus_test(struct mmc_card *card, struct mmc_host *host, u8 opcode,

		  u8 len)

{

	struct mmc_request mrq;

	struct mmc_command cmd;

	struct mmc_data data;

	struct scatterlist sg;

	u8 *data_buf;

	u8 *test_buf;

	int i, err;

	static u8 testdata_8bit[8] = { 0x55, 0xaa, 0, 0, 0, 0, 0, 0 };

	static u8 testdata_4bit[4] = { 0x5a, 0, 0, 0 };



	/* dma onto stack is unsafe/nonportable, but callers to this

	 * routine normally provide temporary on-stack buffers ...

	 */

	data_buf = kmalloc(len, GFP_KERNEL);

	if (!data_buf)

		return -ENOMEM;



	if (len == 8)

		test_buf = testdata_8bit;

	else if (len == 4)

		test_buf = testdata_4bit;

	else {

		printk(KERN_ERR "%s: Invalid bus_width %d\n",

		       mmc_hostname(host), len);

		kfree(data_buf);

		return -EINVAL;

	}



	if (opcode == MMC_BUS_TEST_W)

		memcpy(data_buf, test_buf, len);



	memset(&mrq, 0, sizeof(struct mmc_request));

	memset(&cmd, 0, sizeof(struct mmc_command));

	memset(&data, 0, sizeof(struct mmc_data));



	mrq.cmd = &cmd;

	mrq.data = &data;

	cmd.opcode = opcode;

	cmd.arg = 0;



	/* NOTE HACK:  the MMC_RSP_SPI_R1 is always correct here, but we

	 * rely on callers to never use this with "native" calls for reading

	 * CSD or CID.  Native versions of those commands use the R2 type,

	 * not R1 plus a data block.

	 */

	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;



	data.blksz = len;

	data.blocks = 1;

	if (opcode == MMC_BUS_TEST_R)

		data.flags = MMC_DATA_READ;

	else

		data.flags = MMC_DATA_WRITE;



	data.sg = &sg;

	data.sg_len = 1;

	sg_init_one(&sg, data_buf, len);

	mmc_wait_for_req(host, &mrq);

	err = 0;

	if (opcode == MMC_BUS_TEST_R) {

		for (i = 0; i < len / 4; i++)

			if ((test_buf[i] ^ data_buf[i]) != 0xff) {

				err = -EIO;

				break;

			}

	}

	kfree(data_buf);



	if (cmd.error)

		return cmd.error;

	if (data.error)

		return data.error;



	return err;

}



int mmc_bus_test(struct mmc_card *card, u8 bus_width)

{

	int err, width;



	if (bus_width == MMC_BUS_WIDTH_8)

		width = 8;

	else if (bus_width == MMC_BUS_WIDTH_4)

		width = 4;

	else if (bus_width == MMC_BUS_WIDTH_1)

		return 0; /* no need for test */

	else

		return -EINVAL;



	/*

	 * Ignore errors from BUS_TEST_W.  BUS_TEST_R will fail if there

	 * is a problem.  This improves chances that the test will work.

	 */

	mmc_send_bus_test(card, card->host, MMC_BUS_TEST_W, width);

	err = mmc_send_bus_test(card, card->host, MMC_BUS_TEST_R, width);

	return err;

}

drivers/mmc/core/mmc_ops.h

+1 −0
Original line number Diff line number Diff line
@@ -26,6 +26,7 @@ int mmc_send_cid(struct mmc_host *host, u32 *cid); 
int mmc_spi_read_ocr(struct mmc_host *host, int highcap, u32 *ocrp);

int mmc_spi_set_crc(struct mmc_host *host, int use_crc);

int mmc_card_sleepawake(struct mmc_host *host, int sleep);

int mmc_bus_test(struct mmc_card *card, u8 bus_width);



#endif

drivers/mmc/host/sdhci.c

+6 −1
Original line number Diff line number Diff line
@@ -23,6 +23,7 @@ 


#include <linux/leds.h>



#include <linux/mmc/mmc.h>

#include <linux/mmc/host.h>



#include "sdhci.h"
@@ -1521,7 +1522,11 @@ static void sdhci_data_irq(struct sdhci_host *host, u32 intmask) 


	if (intmask & SDHCI_INT_DATA_TIMEOUT)

		host->data->error = -ETIMEDOUT;

	else if (intmask & (SDHCI_INT_DATA_CRC | SDHCI_INT_DATA_END_BIT))

	else if (intmask & SDHCI_INT_DATA_END_BIT)

		host->data->error = -EILSEQ;

	else if ((intmask & SDHCI_INT_DATA_CRC) &&

		SDHCI_GET_CMD(sdhci_readw(host, SDHCI_COMMAND))

			!= MMC_BUS_TEST_R)

		host->data->error = -EILSEQ;

	else if (intmask & SDHCI_INT_ADMA_ERROR) {

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

drivers/mmc/host/sdhci.h

+1 −0
Original line number Diff line number Diff line
@@ -52,6 +52,7 @@ 
#define  SDHCI_CMD_RESP_SHORT_BUSY 0x03



#define SDHCI_MAKE_CMD(c, f) (((c & 0xff) << 8) | (f & 0xff))

#define SDHCI_GET_CMD(c) ((c>>8) & 0x3f)



#define SDHCI_RESPONSE		0x10

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