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mmc: Fixes for Dual Data Rate (DDR) support

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The DDR support patch needs the following fixes:

- The block driver does not need to know about DDR, any more
  than it needs to know about bus width.
- Not only the card must be switched to DDR mode.  The host
  controller must also be configured, which is done through
  the 'set_ios()' function.
- Do not set the DDR mode state until after the switch command
  is successful.
- Setting block length is not supported in DDR mode.  Make that
  a core function and change the other place it is used (mmc_test)
  also.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
This commit is contained in:
Adrian Hunter
2010-08-24 13:20:26 +03:00
committed by Chris Ball
parent dfc13e8402
commit 0f8d8ea64e
8 changed files with 53 additions and 42 deletions
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21
drivers/mmc/core/mmc.c
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@@ -375,7 +375,7 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
struct mmc_card *oldcard)
{
struct mmc_card *card;
int err;
int err, ddr = 0;
u32 cid[4];
unsigned int max_dtr;
@@ -518,32 +518,32 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
mmc_set_clock(host, max_dtr);
/*
* Activate DDR50 mode (if supported).
* Indicate DDR mode (if supported).
*/
if (mmc_card_highspeed(card)) {
if ((card->ext_csd.card_type & EXT_CSD_CARD_TYPE_DDR_1_8V)
&& (host->caps & (MMC_CAP_1_8V_DDR)))
mmc_card_set_ddr_mode(card);
ddr = 1;
else if ((card->ext_csd.card_type & EXT_CSD_CARD_TYPE_DDR_1_2V)
&& (host->caps & (MMC_CAP_1_2V_DDR)))
mmc_card_set_ddr_mode(card);
ddr = 1;
}
/*
* Activate wide bus (if supported).
* Activate wide bus and DDR (if supported).
*/
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;
if (host->caps & MMC_CAP_8_BIT_DATA) {
if (mmc_card_ddr_mode(card))
if (ddr)
ext_csd_bit = EXT_CSD_DDR_BUS_WIDTH_8;
else
ext_csd_bit = EXT_CSD_BUS_WIDTH_8;
bus_width = MMC_BUS_WIDTH_8;
} else {
if (mmc_card_ddr_mode(card))
if (ddr)
ext_csd_bit = EXT_CSD_DDR_BUS_WIDTH_4;
else
ext_csd_bit = EXT_CSD_BUS_WIDTH_4;
@@ -557,12 +557,13 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
goto free_card;
if (err) {
printk(KERN_WARNING "%s: switch to bus width %d "
printk(KERN_WARNING "%s: switch to bus width %d ddr %d "
"failed\n", mmc_hostname(card->host),
1 << bus_width);
1 << bus_width, ddr);
err = 0;
} else {
mmc_set_bus_width(card->host, bus_width);
mmc_card_set_ddr_mode(card);
mmc_set_bus_width_ddr(card->host, bus_width, ddr);
}
}