linux/drivers/mmc/host/tmio_mmc.c
Ian Molton 4a48998fa1 mfd: TMIO MMC driver
This patch adds support for the MMC subdevice 'cell' commonly found in
TMIO based MFDs.

Signed-off-by: Ian Molton <spyro@f2s.com>
Acked-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-08-10 23:30:16 +02:00

691 lines
17 KiB
C

/*
* linux/drivers/mmc/tmio_mmc.c
*
* Copyright (C) 2004 Ian Molton
* Copyright (C) 2007 Ian Molton
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Driver for the MMC / SD / SDIO cell found in:
*
* TC6393XB TC6391XB TC6387XB T7L66XB
*
* This driver draws mainly on scattered spec sheets, Reverse engineering
* of the toshiba e800 SD driver and some parts of the 2.4 ASIC3 driver (4 bit
* support). (Further 4 bit support from a later datasheet).
*
* TODO:
* Investigate using a workqueue for PIO transfers
* Eliminate FIXMEs
* SDIO support
* Better Power management
* Handle MMC errors better
* double buffer support
*
*/
#include <linux/module.h>
#include <linux/irq.h>
#include <linux/device.h>
#include <linux/delay.h>
#include <linux/mmc/host.h>
#include <linux/mfd/core.h>
#include <linux/mfd/tmio.h>
#include "tmio_mmc.h"
/*
* Fixme - documentation conflicts on what the clock values are for the
* various dividers.
* One document I have says that its a divisor of a 24MHz clock, another 33.
* This probably depends on HCLK for a given platform, so we may need to
* require HCLK be passed to us from the MFD core.
*
*/
static void tmio_mmc_set_clock(struct tmio_mmc_host *host, int new_clock)
{
void __iomem *cnf = host->cnf;
void __iomem *ctl = host->ctl;
u32 clk = 0, clock;
if (new_clock) {
for (clock = 46875, clk = 0x100; new_clock >= (clock<<1); ) {
clock <<= 1;
clk >>= 1;
}
if (clk & 0x1)
clk = 0x20000;
clk >>= 2;
tmio_iowrite8((clk & 0x8000) ? 0 : 1, cnf + CNF_SD_CLK_MODE);
clk |= 0x100;
}
tmio_iowrite16(clk, ctl + CTL_SD_CARD_CLK_CTL);
}
static void tmio_mmc_clk_stop(struct tmio_mmc_host *host)
{
void __iomem *ctl = host->ctl;
tmio_iowrite16(0x0000, ctl + CTL_CLK_AND_WAIT_CTL);
msleep(10);
tmio_iowrite16(tmio_ioread16(ctl + CTL_SD_CARD_CLK_CTL) & ~0x0100,
ctl + CTL_SD_CARD_CLK_CTL);
msleep(10);
}
static void tmio_mmc_clk_start(struct tmio_mmc_host *host)
{
void __iomem *ctl = host->ctl;
tmio_iowrite16(tmio_ioread16(ctl + CTL_SD_CARD_CLK_CTL) | 0x0100,
ctl + CTL_SD_CARD_CLK_CTL);
msleep(10);
tmio_iowrite16(0x0100, ctl + CTL_CLK_AND_WAIT_CTL);
msleep(10);
}
static void reset(struct tmio_mmc_host *host)
{
void __iomem *ctl = host->ctl;
/* FIXME - should we set stop clock reg here */
tmio_iowrite16(0x0000, ctl + CTL_RESET_SD);
tmio_iowrite16(0x0000, ctl + CTL_RESET_SDIO);
msleep(10);
tmio_iowrite16(0x0001, ctl + CTL_RESET_SD);
tmio_iowrite16(0x0001, ctl + CTL_RESET_SDIO);
msleep(10);
}
static void
tmio_mmc_finish_request(struct tmio_mmc_host *host)
{
struct mmc_request *mrq = host->mrq;
host->mrq = NULL;
host->cmd = NULL;
host->data = NULL;
mmc_request_done(host->mmc, mrq);
}
/* These are the bitmasks the tmio chip requires to implement the MMC response
* types. Note that R1 and R6 are the same in this scheme. */
#define APP_CMD 0x0040
#define RESP_NONE 0x0300
#define RESP_R1 0x0400
#define RESP_R1B 0x0500
#define RESP_R2 0x0600
#define RESP_R3 0x0700
#define DATA_PRESENT 0x0800
#define TRANSFER_READ 0x1000
#define TRANSFER_MULTI 0x2000
#define SECURITY_CMD 0x4000
static int
tmio_mmc_start_command(struct tmio_mmc_host *host, struct mmc_command *cmd)
{
void __iomem *ctl = host->ctl;
struct mmc_data *data = host->data;
int c = cmd->opcode;
/* Command 12 is handled by hardware */
if (cmd->opcode == 12 && !cmd->arg) {
tmio_iowrite16(0x001, ctl + CTL_STOP_INTERNAL_ACTION);
return 0;
}
switch (mmc_resp_type(cmd)) {
case MMC_RSP_NONE: c |= RESP_NONE; break;
case MMC_RSP_R1: c |= RESP_R1; break;
case MMC_RSP_R1B: c |= RESP_R1B; break;
case MMC_RSP_R2: c |= RESP_R2; break;
case MMC_RSP_R3: c |= RESP_R3; break;
default:
pr_debug("Unknown response type %d\n", mmc_resp_type(cmd));
return -EINVAL;
}
host->cmd = cmd;
/* FIXME - this seems to be ok comented out but the spec suggest this bit should
* be set when issuing app commands.
* if(cmd->flags & MMC_FLAG_ACMD)
* c |= APP_CMD;
*/
if (data) {
c |= DATA_PRESENT;
if (data->blocks > 1) {
tmio_iowrite16(0x100, ctl + CTL_STOP_INTERNAL_ACTION);
c |= TRANSFER_MULTI;
}
if (data->flags & MMC_DATA_READ)
c |= TRANSFER_READ;
}
enable_mmc_irqs(ctl, TMIO_MASK_CMD);
/* Fire off the command */
tmio_iowrite32(cmd->arg, ctl + CTL_ARG_REG);
tmio_iowrite16(c, ctl + CTL_SD_CMD);
return 0;
}
/* This chip always returns (at least?) as much data as you ask for.
* I'm unsure what happens if you ask for less than a block. This should be
* looked into to ensure that a funny length read doesnt hose the controller.
*
*/
static inline void tmio_mmc_pio_irq(struct tmio_mmc_host *host)
{
void __iomem *ctl = host->ctl;
struct mmc_data *data = host->data;
unsigned short *buf;
unsigned int count;
unsigned long flags;
if (!data) {
pr_debug("Spurious PIO IRQ\n");
return;
}
buf = (unsigned short *)(tmio_mmc_kmap_atomic(host, &flags) +
host->sg_off);
count = host->sg_ptr->length - host->sg_off;
if (count > data->blksz)
count = data->blksz;
pr_debug("count: %08x offset: %08x flags %08x\n",
count, host->sg_off, data->flags);
/* Transfer the data */
if (data->flags & MMC_DATA_READ)
tmio_ioread16_rep(ctl + CTL_SD_DATA_PORT, buf, count >> 1);
else
tmio_iowrite16_rep(ctl + CTL_SD_DATA_PORT, buf, count >> 1);
host->sg_off += count;
tmio_mmc_kunmap_atomic(host, &flags);
if (host->sg_off == host->sg_ptr->length)
tmio_mmc_next_sg(host);
return;
}
static inline void tmio_mmc_data_irq(struct tmio_mmc_host *host)
{
void __iomem *ctl = host->ctl;
struct mmc_data *data = host->data;
struct mmc_command *stop = data->stop;
host->data = NULL;
if (!data) {
pr_debug("Spurious data end IRQ\n");
return;
}
/* FIXME - return correct transfer count on errors */
if (!data->error)
data->bytes_xfered = data->blocks * data->blksz;
else
data->bytes_xfered = 0;
pr_debug("Completed data request\n");
/*FIXME - other drivers allow an optional stop command of any given type
* which we dont do, as the chip can auto generate them.
* Perhaps we can be smarter about when to use auto CMD12 and
* only issue the auto request when we know this is the desired
* stop command, allowing fallback to the stop command the
* upper layers expect. For now, we do what works.
*/
if (data->flags & MMC_DATA_READ)
disable_mmc_irqs(ctl, TMIO_MASK_READOP);
else
disable_mmc_irqs(ctl, TMIO_MASK_WRITEOP);
if (stop) {
if (stop->opcode == 12 && !stop->arg)
tmio_iowrite16(0x000, ctl + CTL_STOP_INTERNAL_ACTION);
else
BUG();
}
tmio_mmc_finish_request(host);
}
static inline void tmio_mmc_cmd_irq(struct tmio_mmc_host *host,
unsigned int stat)
{
void __iomem *ctl = host->ctl, *addr;
struct mmc_command *cmd = host->cmd;
int i;
if (!host->cmd) {
pr_debug("Spurious CMD irq\n");
return;
}
host->cmd = NULL;
/* This controller is sicker than the PXA one. Not only do we need to
* drop the top 8 bits of the first response word, we also need to
* modify the order of the response for short response command types.
*/
for (i = 3, addr = ctl + CTL_RESPONSE ; i >= 0 ; i--, addr += 4)
cmd->resp[i] = tmio_ioread32(addr);
if (cmd->flags & MMC_RSP_136) {
cmd->resp[0] = (cmd->resp[0] << 8) | (cmd->resp[1] >> 24);
cmd->resp[1] = (cmd->resp[1] << 8) | (cmd->resp[2] >> 24);
cmd->resp[2] = (cmd->resp[2] << 8) | (cmd->resp[3] >> 24);
cmd->resp[3] <<= 8;
} else if (cmd->flags & MMC_RSP_R3) {
cmd->resp[0] = cmd->resp[3];
}
if (stat & TMIO_STAT_CMDTIMEOUT)
cmd->error = -ETIMEDOUT;
else if (stat & TMIO_STAT_CRCFAIL && cmd->flags & MMC_RSP_CRC)
cmd->error = -EILSEQ;
/* If there is data to handle we enable data IRQs here, and
* we will ultimatley finish the request in the data_end handler.
* If theres no data or we encountered an error, finish now.
*/
if (host->data && !cmd->error) {
if (host->data->flags & MMC_DATA_READ)
enable_mmc_irqs(ctl, TMIO_MASK_READOP);
else
enable_mmc_irqs(ctl, TMIO_MASK_WRITEOP);
} else {
tmio_mmc_finish_request(host);
}
return;
}
static irqreturn_t tmio_mmc_irq(int irq, void *devid)
{
struct tmio_mmc_host *host = devid;
void __iomem *ctl = host->ctl;
unsigned int ireg, irq_mask, status;
pr_debug("MMC IRQ begin\n");
status = tmio_ioread32(ctl + CTL_STATUS);
irq_mask = tmio_ioread32(ctl + CTL_IRQ_MASK);
ireg = status & TMIO_MASK_IRQ & ~irq_mask;
pr_debug_status(status);
pr_debug_status(ireg);
if (!ireg) {
disable_mmc_irqs(ctl, status & ~irq_mask);
pr_debug("tmio_mmc: Spurious irq, disabling! "
"0x%08x 0x%08x 0x%08x\n", status, irq_mask, ireg);
pr_debug_status(status);
goto out;
}
while (ireg) {
/* Card insert / remove attempts */
if (ireg & (TMIO_STAT_CARD_INSERT | TMIO_STAT_CARD_REMOVE)) {
ack_mmc_irqs(ctl, TMIO_STAT_CARD_INSERT |
TMIO_STAT_CARD_REMOVE);
mmc_detect_change(host->mmc, 0);
}
/* CRC and other errors */
/* if (ireg & TMIO_STAT_ERR_IRQ)
* handled |= tmio_error_irq(host, irq, stat);
*/
/* Command completion */
if (ireg & TMIO_MASK_CMD) {
ack_mmc_irqs(ctl, TMIO_MASK_CMD);
tmio_mmc_cmd_irq(host, status);
}
/* Data transfer */
if (ireg & (TMIO_STAT_RXRDY | TMIO_STAT_TXRQ)) {
ack_mmc_irqs(ctl, TMIO_STAT_RXRDY | TMIO_STAT_TXRQ);
tmio_mmc_pio_irq(host);
}
/* Data transfer completion */
if (ireg & TMIO_STAT_DATAEND) {
ack_mmc_irqs(ctl, TMIO_STAT_DATAEND);
tmio_mmc_data_irq(host);
}
/* Check status - keep going until we've handled it all */
status = tmio_ioread32(ctl + CTL_STATUS);
irq_mask = tmio_ioread32(ctl + CTL_IRQ_MASK);
ireg = status & TMIO_MASK_IRQ & ~irq_mask;
pr_debug("Status at end of loop: %08x\n", status);
pr_debug_status(status);
}
pr_debug("MMC IRQ end\n");
out:
return IRQ_HANDLED;
}
static int tmio_mmc_start_data(struct tmio_mmc_host *host,
struct mmc_data *data)
{
void __iomem *ctl = host->ctl;
pr_debug("setup data transfer: blocksize %08x nr_blocks %d\n",
data->blksz, data->blocks);
/* Hardware cannot perform 1 and 2 byte requests in 4 bit mode */
if (data->blksz < 4 && host->mmc->ios.bus_width == MMC_BUS_WIDTH_4) {
printk(KERN_ERR "%s: %d byte block unsupported in 4 bit mode\n",
mmc_hostname(host->mmc), data->blksz);
return -EINVAL;
}
tmio_mmc_init_sg(host, data);
host->data = data;
/* Set transfer length / blocksize */
tmio_iowrite16(data->blksz, ctl + CTL_SD_XFER_LEN);
tmio_iowrite16(data->blocks, ctl + CTL_XFER_BLK_COUNT);
return 0;
}
/* Process requests from the MMC layer */
static void tmio_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
{
struct tmio_mmc_host *host = mmc_priv(mmc);
int ret;
if (host->mrq)
pr_debug("request not null\n");
host->mrq = mrq;
if (mrq->data) {
ret = tmio_mmc_start_data(host, mrq->data);
if (ret)
goto fail;
}
ret = tmio_mmc_start_command(host, mrq->cmd);
if (!ret)
return;
fail:
mrq->cmd->error = ret;
mmc_request_done(mmc, mrq);
}
/* Set MMC clock / power.
* Note: This controller uses a simple divider scheme therefore it cannot
* run a MMC card at full speed (20MHz). The max clock is 24MHz on SD, but as
* MMC wont run that fast, it has to be clocked at 12MHz which is the next
* slowest setting.
*/
static void tmio_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
{
struct tmio_mmc_host *host = mmc_priv(mmc);
void __iomem *cnf = host->cnf;
void __iomem *ctl = host->ctl;
if (ios->clock)
tmio_mmc_set_clock(host, ios->clock);
/* Power sequence - OFF -> ON -> UP */
switch (ios->power_mode) {
case MMC_POWER_OFF: /* power down SD bus */
tmio_iowrite8(0x00, cnf + CNF_PWR_CTL_2);
tmio_mmc_clk_stop(host);
break;
case MMC_POWER_ON: /* power up SD bus */
tmio_iowrite8(0x02, cnf + CNF_PWR_CTL_2);
break;
case MMC_POWER_UP: /* start bus clock */
tmio_mmc_clk_start(host);
break;
}
switch (ios->bus_width) {
case MMC_BUS_WIDTH_1:
tmio_iowrite16(0x80e0, ctl + CTL_SD_MEM_CARD_OPT);
break;
case MMC_BUS_WIDTH_4:
tmio_iowrite16(0x00e0, ctl + CTL_SD_MEM_CARD_OPT);
break;
}
/* Let things settle. delay taken from winCE driver */
udelay(140);
}
static int tmio_mmc_get_ro(struct mmc_host *mmc)
{
struct tmio_mmc_host *host = mmc_priv(mmc);
void __iomem *ctl = host->ctl;
return (tmio_ioread16(ctl + CTL_STATUS) & TMIO_STAT_WRPROTECT) ? 0 : 1;
}
static struct mmc_host_ops tmio_mmc_ops = {
.request = tmio_mmc_request,
.set_ios = tmio_mmc_set_ios,
.get_ro = tmio_mmc_get_ro,
};
#ifdef CONFIG_PM
static int tmio_mmc_suspend(struct platform_device *dev, pm_message_t state)
{
struct mfd_cell *cell = (struct mfd_cell *)dev->dev.platform_data;
struct mmc_host *mmc = platform_get_drvdata(dev);
int ret;
ret = mmc_suspend_host(mmc, state);
/* Tell MFD core it can disable us now.*/
if (!ret && cell->disable)
cell->disable(dev);
return ret;
}
static int tmio_mmc_resume(struct platform_device *dev)
{
struct mfd_cell *cell = (struct mfd_cell *)dev->dev.platform_data;
struct mmc_host *mmc = platform_get_drvdata(dev);
struct tmio_mmc_host *host = mmc_priv(mmc);
void __iomem *cnf = host->cnf;
int ret = 0;
/* Enable the MMC/SD Control registers */
tmio_iowrite16(SDCREN, cnf + CNF_CMD);
tmio_iowrite32(dev->resource[0].start & 0xfffe, cnf + CNF_CTL_BASE);
/* Tell the MFD core we are ready to be enabled */
if (cell->enable) {
ret = cell->enable(dev);
if (ret)
goto out;
}
mmc_resume_host(mmc);
out:
return ret;
}
#else
#define tmio_mmc_suspend NULL
#define tmio_mmc_resume NULL
#endif
static int __devinit tmio_mmc_probe(struct platform_device *dev)
{
struct mfd_cell *cell = (struct mfd_cell *)dev->dev.platform_data;
struct resource *res_ctl, *res_cnf;
struct tmio_mmc_host *host;
struct mmc_host *mmc;
int ret = -ENOMEM;
if (dev->num_resources != 3)
goto out;
res_ctl = platform_get_resource(dev, IORESOURCE_MEM, 0);
res_cnf = platform_get_resource(dev, IORESOURCE_MEM, 1);
if (!res_ctl || !res_cnf) {
ret = -EINVAL;
goto out;
}
mmc = mmc_alloc_host(sizeof(struct tmio_mmc_host), &dev->dev);
if (!mmc)
goto out;
host = mmc_priv(mmc);
host->mmc = mmc;
platform_set_drvdata(dev, mmc);
host->ctl = ioremap(res_ctl->start, res_ctl->end - res_ctl->start);
if (!host->ctl)
goto host_free;
host->cnf = ioremap(res_cnf->start, res_cnf->end - res_cnf->start);
if (!host->cnf)
goto unmap_ctl;
mmc->ops = &tmio_mmc_ops;
mmc->caps = MMC_CAP_4_BIT_DATA;
mmc->f_min = 46875; /* 24000000 / 512 */
mmc->f_max = 24000000;
mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
/* Enable the MMC/SD Control registers */
tmio_iowrite16(SDCREN, host->cnf + CNF_CMD);
tmio_iowrite32(dev->resource[0].start & 0xfffe,
host->cnf + CNF_CTL_BASE);
/* Tell the MFD core we are ready to be enabled */
if (cell->enable) {
ret = cell->enable(dev);
if (ret)
goto unmap_cnf;
}
/* Disable SD power during suspend */
tmio_iowrite8(0x01, host->cnf + CNF_PWR_CTL_3);
/* The below is required but why? FIXME */
tmio_iowrite8(0x1f, host->cnf + CNF_STOP_CLK_CTL);
/* Power down SD bus*/
tmio_iowrite8(0x0, host->cnf + CNF_PWR_CTL_2);
tmio_mmc_clk_stop(host);
reset(host);
ret = platform_get_irq(dev, 0);
if (ret >= 0)
host->irq = ret;
else
goto unmap_cnf;
disable_mmc_irqs(host->ctl, TMIO_MASK_ALL);
ret = request_irq(host->irq, tmio_mmc_irq, IRQF_DISABLED, "tmio-mmc",
host);
if (ret)
goto unmap_cnf;
set_irq_type(host->irq, IRQ_TYPE_EDGE_FALLING);
mmc_add_host(mmc);
printk(KERN_INFO "%s at 0x%08lx irq %d\n", mmc_hostname(host->mmc),
(unsigned long)host->ctl, host->irq);
/* Unmask the IRQs we want to know about */
enable_mmc_irqs(host->ctl, TMIO_MASK_IRQ);
return 0;
unmap_cnf:
iounmap(host->cnf);
unmap_ctl:
iounmap(host->ctl);
host_free:
mmc_free_host(mmc);
out:
return ret;
}
static int __devexit tmio_mmc_remove(struct platform_device *dev)
{
struct mmc_host *mmc = platform_get_drvdata(dev);
platform_set_drvdata(dev, NULL);
if (mmc) {
struct tmio_mmc_host *host = mmc_priv(mmc);
mmc_remove_host(mmc);
mmc_free_host(mmc);
free_irq(host->irq, host);
iounmap(host->ctl);
iounmap(host->cnf);
}
return 0;
}
/* ------------------- device registration ----------------------- */
static struct platform_driver tmio_mmc_driver = {
.driver = {
.name = "tmio-mmc",
.owner = THIS_MODULE,
},
.probe = tmio_mmc_probe,
.remove = __devexit_p(tmio_mmc_remove),
.suspend = tmio_mmc_suspend,
.resume = tmio_mmc_resume,
};
static int __init tmio_mmc_init(void)
{
return platform_driver_register(&tmio_mmc_driver);
}
static void __exit tmio_mmc_exit(void)
{
platform_driver_unregister(&tmio_mmc_driver);
}
module_init(tmio_mmc_init);
module_exit(tmio_mmc_exit);
MODULE_DESCRIPTION("Toshiba TMIO SD/MMC driver");
MODULE_AUTHOR("Ian Molton <spyro@f2s.com>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:tmio-mmc");