kernel-fxtec-pro1x/drivers/mmc/core/mmc_ops.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

380 lines
7.5 KiB
C

/*
* linux/drivers/mmc/core/mmc_ops.h
*
* 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/types.h>
#include <asm/scatterlist.h>
#include <linux/scatterlist.h>
#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
#include <linux/mmc/mmc.h>
#include "core.h"
#include "mmc_ops.h"
static int _mmc_select_card(struct mmc_host *host, struct mmc_card *card)
{
int err;
struct mmc_command cmd;
BUG_ON(!host);
memset(&cmd, 0, sizeof(struct mmc_command));
cmd.opcode = MMC_SELECT_CARD;
if (card) {
cmd.arg = card->rca << 16;
cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
} else {
cmd.arg = 0;
cmd.flags = MMC_RSP_NONE | MMC_CMD_AC;
}
err = mmc_wait_for_cmd(host, &cmd, MMC_CMD_RETRIES);
if (err)
return err;
return 0;
}
int mmc_select_card(struct mmc_card *card)
{
BUG_ON(!card);
return _mmc_select_card(card->host, card);
}
int mmc_deselect_cards(struct mmc_host *host)
{
return _mmc_select_card(host, NULL);
}
int mmc_go_idle(struct mmc_host *host)
{
int err;
struct mmc_command cmd;
/*
* Non-SPI hosts need to prevent chipselect going active during
* GO_IDLE; that would put chips into SPI mode. Remind them of
* that in case of hardware that won't pull up DAT3/nCS otherwise.
*
* SPI hosts ignore ios.chip_select; it's managed according to
* rules that must accomodate non-MMC slaves which this layer
* won't even know about.
*/
if (!mmc_host_is_spi(host)) {
mmc_set_chip_select(host, MMC_CS_HIGH);
mmc_delay(1);
}
memset(&cmd, 0, sizeof(struct mmc_command));
cmd.opcode = MMC_GO_IDLE_STATE;
cmd.arg = 0;
cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_NONE | MMC_CMD_BC;
err = mmc_wait_for_cmd(host, &cmd, 0);
mmc_delay(1);
if (!mmc_host_is_spi(host)) {
mmc_set_chip_select(host, MMC_CS_DONTCARE);
mmc_delay(1);
}
host->use_spi_crc = 0;
return err;
}
int mmc_send_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr)
{
struct mmc_command cmd;
int i, err = 0;
BUG_ON(!host);
memset(&cmd, 0, sizeof(struct mmc_command));
cmd.opcode = MMC_SEND_OP_COND;
cmd.arg = mmc_host_is_spi(host) ? 0 : ocr;
cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R3 | MMC_CMD_BCR;
for (i = 100; i; i--) {
err = mmc_wait_for_cmd(host, &cmd, 0);
if (err)
break;
/* if we're just probing, do a single pass */
if (ocr == 0)
break;
/* otherwise wait until reset completes */
if (mmc_host_is_spi(host)) {
if (!(cmd.resp[0] & R1_SPI_IDLE))
break;
} else {
if (cmd.resp[0] & MMC_CARD_BUSY)
break;
}
err = -ETIMEDOUT;
mmc_delay(10);
}
if (rocr && !mmc_host_is_spi(host))
*rocr = cmd.resp[0];
return err;
}
int mmc_all_send_cid(struct mmc_host *host, u32 *cid)
{
int err;
struct mmc_command cmd;
BUG_ON(!host);
BUG_ON(!cid);
memset(&cmd, 0, sizeof(struct mmc_command));
cmd.opcode = MMC_ALL_SEND_CID;
cmd.arg = 0;
cmd.flags = MMC_RSP_R2 | MMC_CMD_BCR;
err = mmc_wait_for_cmd(host, &cmd, MMC_CMD_RETRIES);
if (err)
return err;
memcpy(cid, cmd.resp, sizeof(u32) * 4);
return 0;
}
int mmc_set_relative_addr(struct mmc_card *card)
{
int err;
struct mmc_command cmd;
BUG_ON(!card);
BUG_ON(!card->host);
memset(&cmd, 0, sizeof(struct mmc_command));
cmd.opcode = MMC_SET_RELATIVE_ADDR;
cmd.arg = card->rca << 16;
cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
err = mmc_wait_for_cmd(card->host, &cmd, MMC_CMD_RETRIES);
if (err)
return err;
return 0;
}
static int
mmc_send_cxd_native(struct mmc_host *host, u32 arg, u32 *cxd, int opcode)
{
int err;
struct mmc_command cmd;
BUG_ON(!host);
BUG_ON(!cxd);
memset(&cmd, 0, sizeof(struct mmc_command));
cmd.opcode = opcode;
cmd.arg = arg;
cmd.flags = MMC_RSP_R2 | MMC_CMD_AC;
err = mmc_wait_for_cmd(host, &cmd, MMC_CMD_RETRIES);
if (err)
return err;
memcpy(cxd, cmd.resp, sizeof(u32) * 4);
return 0;
}
static int
mmc_send_cxd_data(struct mmc_card *card, struct mmc_host *host,
u32 opcode, void *buf, unsigned len)
{
struct mmc_request mrq;
struct mmc_command cmd;
struct mmc_data data;
struct scatterlist sg;
void *data_buf;
/* 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 == NULL)
return -ENOMEM;
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;
data.flags = MMC_DATA_READ;
data.sg = &sg;
data.sg_len = 1;
sg_init_one(&sg, data_buf, len);
if (card)
mmc_set_data_timeout(&data, card);
mmc_wait_for_req(host, &mrq);
memcpy(buf, data_buf, len);
kfree(data_buf);
if (cmd.error)
return cmd.error;
if (data.error)
return data.error;
return 0;
}
int mmc_send_csd(struct mmc_card *card, u32 *csd)
{
if (!mmc_host_is_spi(card->host))
return mmc_send_cxd_native(card->host, card->rca << 16,
csd, MMC_SEND_CSD);
return mmc_send_cxd_data(card, card->host, MMC_SEND_CSD, csd, 16);
}
int mmc_send_cid(struct mmc_host *host, u32 *cid)
{
if (!mmc_host_is_spi(host)) {
if (!host->card)
return -EINVAL;
return mmc_send_cxd_native(host, host->card->rca << 16,
cid, MMC_SEND_CID);
}
return mmc_send_cxd_data(NULL, host, MMC_SEND_CID, cid, 16);
}
int mmc_send_ext_csd(struct mmc_card *card, u8 *ext_csd)
{
return mmc_send_cxd_data(card, card->host, MMC_SEND_EXT_CSD,
ext_csd, 512);
}
int mmc_spi_read_ocr(struct mmc_host *host, int highcap, u32 *ocrp)
{
struct mmc_command cmd;
int err;
memset(&cmd, 0, sizeof(struct mmc_command));
cmd.opcode = MMC_SPI_READ_OCR;
cmd.arg = highcap ? (1 << 30) : 0;
cmd.flags = MMC_RSP_SPI_R3;
err = mmc_wait_for_cmd(host, &cmd, 0);
*ocrp = cmd.resp[1];
return err;
}
int mmc_spi_set_crc(struct mmc_host *host, int use_crc)
{
struct mmc_command cmd;
int err;
memset(&cmd, 0, sizeof(struct mmc_command));
cmd.opcode = MMC_SPI_CRC_ON_OFF;
cmd.flags = MMC_RSP_SPI_R1;
cmd.arg = use_crc;
err = mmc_wait_for_cmd(host, &cmd, 0);
if (!err)
host->use_spi_crc = use_crc;
return err;
}
int mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value)
{
int err;
struct mmc_command cmd;
BUG_ON(!card);
BUG_ON(!card->host);
memset(&cmd, 0, sizeof(struct mmc_command));
cmd.opcode = MMC_SWITCH;
cmd.arg = (MMC_SWITCH_MODE_WRITE_BYTE << 24) |
(index << 16) |
(value << 8) |
set;
cmd.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
err = mmc_wait_for_cmd(card->host, &cmd, MMC_CMD_RETRIES);
if (err)
return err;
return 0;
}
int mmc_send_status(struct mmc_card *card, u32 *status)
{
int err;
struct mmc_command cmd;
BUG_ON(!card);
BUG_ON(!card->host);
memset(&cmd, 0, sizeof(struct mmc_command));
cmd.opcode = MMC_SEND_STATUS;
if (!mmc_host_is_spi(card->host))
cmd.arg = card->rca << 16;
cmd.flags = MMC_RSP_SPI_R2 | MMC_RSP_R1 | MMC_CMD_AC;
err = mmc_wait_for_cmd(card->host, &cmd, MMC_CMD_RETRIES);
if (err)
return err;
/* NOTE: callers are required to understand the difference
* between "native" and SPI format status words!
*/
if (status)
*status = cmd.resp[0];
return 0;
}