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linux/drivers/mmc/core/sdio.c
David Brownell af51715079 MMC core learns about SPI
Teach the MMC/SD/SDIO core about using SPI mode.

 - Use mmc_host_is_spi() so enumeration works through SPI signaling
   and protocols, not just the native versions.

 - Provide the SPI response type flags with each request issued,
   including requests from the new lock/unlock code.

 - Understand that cmd->resp[0] and mmc_get_status() results for SPI
   return different values than for "native" MMC/SD protocol; this
   affects resetting, checking card lock status, and some others.

 - Understand that some commands act a bit differently ... notably:
     * OP_COND command doesn't return the OCR
     * APP_CMD status doesn't have an R1_APP_CMD analogue

Those changes required some new and updated primitives:

 - Provide utilities to access two SPI-only requests, and one
   request that wasn't previously needed:
     * mmc_spi_read_ocr() ... SPI only
     * mmc_spi_set_crc() ... SPI only (override by module parm)
     * mmc_send_cid() ... for use without broadcast mode

 - Updated internal routines:
     * Previous mmc_send_csd() modified into mmc_send_cxd_native();
       it uses native "R2" responses, which include 16 bytes of data.
     * Previous mmc_send_ext_csd() becomes new mmc_send_cxd_data()
       helper for command-and-data access
     * Bugfix to that mmc_send_cxd_data() code:  dma-to-stack is
       unsafe/nonportable, so kmalloc a bounce buffer instead.

 - Modified mmc_send_ext_csd() now uses mmc_send_cxd_data() helper

 - Modified mmc_send_csd(), and new mmc_spi_send_cid(), routines use
   those helper routines based on whether they're native or SPI

The newest categories of cards supported by the MMC stack aren't expected
to work yet with SPI:  MMC or SD cards with over 4GB data, and SDIO.
All those cards support SPI mode, so eventually they should work too.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
2007-09-23 21:51:30 +02:00

396 lines
7.1 KiB
C

/*
* linux/drivers/mmc/sdio.c
*
* Copyright 2006-2007 Pierre Ossman
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*/
#include <linux/err.h>
#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
#include <linux/mmc/sdio.h>
#include <linux/mmc/sdio_func.h>
#include "core.h"
#include "bus.h"
#include "sdio_bus.h"
#include "mmc_ops.h"
#include "sd_ops.h"
#include "sdio_ops.h"
#include "sdio_cis.h"
static int sdio_read_fbr(struct sdio_func *func)
{
int ret;
unsigned char data;
ret = mmc_io_rw_direct(func->card, 0, 0,
SDIO_FBR_BASE(func->num) + SDIO_FBR_STD_IF, 0, &data);
if (ret)
goto out;
data &= 0x0f;
if (data == 0x0f) {
ret = mmc_io_rw_direct(func->card, 0, 0,
SDIO_FBR_BASE(func->num) + SDIO_FBR_STD_IF_EXT, 0, &data);
if (ret)
goto out;
}
func->class = data;
out:
return ret;
}
static int sdio_init_func(struct mmc_card *card, unsigned int fn)
{
int ret;
struct sdio_func *func;
BUG_ON(fn > SDIO_MAX_FUNCS);
func = sdio_alloc_func(card);
if (IS_ERR(func))
return PTR_ERR(func);
func->num = fn;
ret = sdio_read_fbr(func);
if (ret)
goto fail;
ret = sdio_read_func_cis(func);
if (ret)
goto fail;
card->sdio_func[fn - 1] = func;
return 0;
fail:
/*
* It is okay to remove the function here even though we hold
* the host lock as we haven't registered the device yet.
*/
sdio_remove_func(func);
return ret;
}
static int sdio_read_cccr(struct mmc_card *card)
{
int ret;
int cccr_vsn;
unsigned char data;
memset(&card->cccr, 0, sizeof(struct sdio_cccr));
ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_CCCR, 0, &data);
if (ret)
goto out;
cccr_vsn = data & 0x0f;
if (cccr_vsn > SDIO_CCCR_REV_1_20) {
printk(KERN_ERR "%s: unrecognised CCCR structure version %d\n",
mmc_hostname(card->host), cccr_vsn);
return -EINVAL;
}
card->cccr.sdio_vsn = (data & 0xf0) >> 4;
ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_CAPS, 0, &data);
if (ret)
goto out;
if (data & SDIO_CCCR_CAP_SMB)
card->cccr.multi_block = 1;
if (data & SDIO_CCCR_CAP_LSC)
card->cccr.low_speed = 1;
if (data & SDIO_CCCR_CAP_4BLS)
card->cccr.wide_bus = 1;
if (cccr_vsn >= SDIO_CCCR_REV_1_10) {
ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_POWER, 0, &data);
if (ret)
goto out;
if (data & SDIO_POWER_SMPC)
card->cccr.high_power = 1;
}
if (cccr_vsn >= SDIO_CCCR_REV_1_20) {
ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_SPEED, 0, &data);
if (ret)
goto out;
if (data & SDIO_SPEED_SHS)
card->cccr.high_speed = 1;
}
out:
return ret;
}
static int sdio_enable_wide(struct mmc_card *card)
{
int ret;
u8 ctrl;
if (!(card->host->caps & MMC_CAP_4_BIT_DATA))
return 0;
if (card->cccr.low_speed && !card->cccr.wide_bus)
return 0;
ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_IF, 0, &ctrl);
if (ret)
return ret;
ctrl |= SDIO_BUS_WIDTH_4BIT;
ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_IF, ctrl, NULL);
if (ret)
return ret;
mmc_set_bus_width(card->host, MMC_BUS_WIDTH_4);
return 0;
}
/*
* Host is being removed. Free up the current card.
*/
static void mmc_sdio_remove(struct mmc_host *host)
{
int i;
BUG_ON(!host);
BUG_ON(!host->card);
for (i = 0;i < host->card->sdio_funcs;i++) {
if (host->card->sdio_func[i]) {
sdio_remove_func(host->card->sdio_func[i]);
host->card->sdio_func[i] = NULL;
}
}
mmc_remove_card(host->card);
host->card = NULL;
}
/*
* Card detection callback from host.
*/
static void mmc_sdio_detect(struct mmc_host *host)
{
int err;
BUG_ON(!host);
BUG_ON(!host->card);
mmc_claim_host(host);
/*
* Just check if our card has been removed.
*/
err = mmc_select_card(host->card);
mmc_release_host(host);
if (err) {
mmc_sdio_remove(host);
mmc_claim_host(host);
mmc_detach_bus(host);
mmc_release_host(host);
}
}
static const struct mmc_bus_ops mmc_sdio_ops = {
.remove = mmc_sdio_remove,
.detect = mmc_sdio_detect,
};
/*
* Starting point for SDIO card init.
*/
int mmc_attach_sdio(struct mmc_host *host, u32 ocr)
{
int err;
int i, funcs;
struct mmc_card *card;
BUG_ON(!host);
WARN_ON(!host->claimed);
mmc_attach_bus(host, &mmc_sdio_ops);
/*
* Sanity check the voltages that the card claims to
* support.
*/
if (ocr & 0x7F) {
printk(KERN_WARNING "%s: card claims to support voltages "
"below the defined range. These will be ignored.\n",
mmc_hostname(host));
ocr &= ~0x7F;
}
if (ocr & MMC_VDD_165_195) {
printk(KERN_WARNING "%s: SDIO card claims to support the "
"incompletely defined 'low voltage range'. This "
"will be ignored.\n", mmc_hostname(host));
ocr &= ~MMC_VDD_165_195;
}
host->ocr = mmc_select_voltage(host, ocr);
/*
* Can we support the voltage(s) of the card(s)?
*/
if (!host->ocr) {
err = -EINVAL;
goto err;
}
/*
* Inform the card of the voltage
*/
err = mmc_send_io_op_cond(host, host->ocr, &ocr);
if (err)
goto err;
/*
* For SPI, enable CRC as appropriate.
*/
if (mmc_host_is_spi(host)) {
err = mmc_spi_set_crc(host, use_spi_crc);
if (err)
goto err;
}
/*
* The number of functions on the card is encoded inside
* the ocr.
*/
funcs = (ocr & 0x70000000) >> 28;
/*
* Allocate card structure.
*/
card = mmc_alloc_card(host);
if (IS_ERR(card)) {
err = PTR_ERR(card);
goto err;
}
card->type = MMC_TYPE_SDIO;
card->sdio_funcs = funcs;
host->card = card;
/*
* For native busses: set card RCA and quit open drain mode.
*/
if (!mmc_host_is_spi(host)) {
err = mmc_send_relative_addr(host, &card->rca);
if (err)
goto remove;
mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);
}
/*
* Select card, as all following commands rely on that.
*/
if (!mmc_host_is_spi(host)) {
err = mmc_select_card(card);
if (err)
goto remove;
}
/*
* Read the common registers.
*/
err = sdio_read_cccr(card);
if (err)
goto remove;
/*
* Read the common CIS tuples.
*/
err = sdio_read_common_cis(card);
if (err)
goto remove;
/*
* No support for high-speed yet, so just set
* the card's maximum speed.
*/
mmc_set_clock(host, card->cis.max_dtr);
/*
* Switch to wider bus (if supported).
*/
err = sdio_enable_wide(card);
if (err)
goto remove;
/*
* Initialize (but don't add) all present functions.
*/
for (i = 0;i < funcs;i++) {
err = sdio_init_func(host->card, i + 1);
if (err)
goto remove;
}
mmc_release_host(host);
/*
* First add the card to the driver model...
*/
err = mmc_add_card(host->card);
if (err)
goto remove_added;
/*
* ...then the SDIO functions.
*/
for (i = 0;i < funcs;i++) {
err = sdio_add_func(host->card->sdio_func[i]);
if (err)
goto remove_added;
}
return 0;
remove_added:
/* Remove without lock if the device has been added. */
mmc_sdio_remove(host);
mmc_claim_host(host);
remove:
/* And with lock if it hasn't been added. */
if (host->card)
mmc_sdio_remove(host);
err:
mmc_detach_bus(host);
mmc_release_host(host);
printk(KERN_ERR "%s: error %d whilst initialising SDIO card\n",
mmc_hostname(host), err);
return err;
}