- 根目录:
- drivers
- mmc
- host
- android-goldfish.c
/*
* Copyright 2007, Google Inc.
* Copyright 2012, Intel Inc.
*
* based on omap.c driver, which was
* Copyright (C) 2004 Nokia Corporation
* Written by Tuukka Tikkanen and Juha Yrjölä <juha.yrjola@nokia.com>
* Misc hacks here and there by Tony Lindgren <tony@atomide.com>
* Other hacks (DMA, SD, etc) by David Brownell
*
* 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.
*/
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/major.h>
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/hdreg.h>
#include <linux/kdev_t.h>
#include <linux/blkdev.h>
#include <linux/mutex.h>
#include <linux/scatterlist.h>
#include <linux/mmc/mmc.h>
#include <linux/mmc/sdio.h>
#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/dma-mapping.h>
#include <linux/delay.h>
#include <linux/spinlock.h>
#include <linux/timer.h>
#include <linux/clk.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/scatterlist.h>
#include <asm/types.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#define DRIVER_NAME "goldfish_mmc"
#define BUFFER_SIZE 16384
#define GOLDFISH_MMC_READ(host, addr) (readl(host->reg_base + addr))
#define GOLDFISH_MMC_WRITE(host, addr, x) (writel(x, host->reg_base + addr))
enum {
/* status register */
MMC_INT_STATUS = 0x00,
/* set this to enable IRQ */
MMC_INT_ENABLE = 0x04,
/* set this to specify buffer address */
MMC_SET_BUFFER = 0x08,
/* MMC command number */
MMC_CMD = 0x0C,
/* MMC argument */
MMC_ARG = 0x10,
/* MMC response (or R2 bits 0 - 31) */
MMC_RESP_0 = 0x14,
/* MMC R2 response bits 32 - 63 */
MMC_RESP_1 = 0x18,
/* MMC R2 response bits 64 - 95 */
MMC_RESP_2 = 0x1C,
/* MMC R2 response bits 96 - 127 */
MMC_RESP_3 = 0x20,
MMC_BLOCK_LENGTH = 0x24,
MMC_BLOCK_COUNT = 0x28,
/* MMC state flags */
MMC_STATE = 0x2C,
/* MMC_INT_STATUS bits */
MMC_STAT_END_OF_CMD = 1U << 0,
MMC_STAT_END_OF_DATA = 1U << 1,
MMC_STAT_STATE_CHANGE = 1U << 2,
MMC_STAT_CMD_TIMEOUT = 1U << 3,
/* MMC_STATE bits */
MMC_STATE_INSERTED = 1U << 0,
MMC_STATE_READ_ONLY = 1U << 1,
};
/*
* Command types
*/
#define OMAP_MMC_CMDTYPE_BC 0
#define OMAP_MMC_CMDTYPE_BCR 1
#define OMAP_MMC_CMDTYPE_AC 2
#define OMAP_MMC_CMDTYPE_ADTC 3
struct goldfish_mmc_host {
struct mmc_request *mrq;
struct mmc_command *cmd;
struct mmc_data *data;
struct mmc_host *mmc;
struct device *dev;
unsigned char id; /* 16xx chips have 2 MMC blocks */
void __iomem *virt_base;
unsigned int phys_base;
int irq;
unsigned char bus_mode;
unsigned char hw_bus_mode;
unsigned int sg_len;
unsigned dma_done:1;
unsigned dma_in_use:1;
void __iomem *reg_base;
};
static inline int
goldfish_mmc_cover_is_open(struct goldfish_mmc_host *host)
{
return 0;
}
static ssize_t
goldfish_mmc_show_cover_switch(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct goldfish_mmc_host *host = dev_get_drvdata(dev);
return sprintf(buf, "%s\n", goldfish_mmc_cover_is_open(host) ? "open" :
"closed");
}
static DEVICE_ATTR(cover_switch, S_IRUGO, goldfish_mmc_show_cover_switch, NULL);
static void
goldfish_mmc_start_command(struct goldfish_mmc_host *host, struct mmc_command *cmd)
{
u32 cmdreg;
u32 resptype;
u32 cmdtype;
host->cmd = cmd;
resptype = 0;
cmdtype = 0;
/* Our hardware needs to know exact type */
switch (mmc_resp_type(cmd)) {
case MMC_RSP_NONE:
break;
case MMC_RSP_R1:
case MMC_RSP_R1B:
/* resp 1, 1b, 6, 7 */
resptype = 1;
break;
case MMC_RSP_R2:
resptype = 2;
break;
case MMC_RSP_R3:
resptype = 3;
break;
default:
dev_err(mmc_dev(host->mmc),
"Invalid response type: %04x\n", mmc_resp_type(cmd));
break;
}
if (mmc_cmd_type(cmd) == MMC_CMD_ADTC)
cmdtype = OMAP_MMC_CMDTYPE_ADTC;
else if (mmc_cmd_type(cmd) == MMC_CMD_BC)
cmdtype = OMAP_MMC_CMDTYPE_BC;
else if (mmc_cmd_type(cmd) == MMC_CMD_BCR)
cmdtype = OMAP_MMC_CMDTYPE_BCR;
else
cmdtype = OMAP_MMC_CMDTYPE_AC;
cmdreg = cmd->opcode | (resptype << 8) | (cmdtype << 12);
if (host->bus_mode == MMC_BUSMODE_OPENDRAIN)
cmdreg |= 1 << 6;
if (cmd->flags & MMC_RSP_BUSY)
cmdreg |= 1 << 11;
if (host->data && !(host->data->flags & MMC_DATA_WRITE))
cmdreg |= 1 << 15;
GOLDFISH_MMC_WRITE(host, MMC_ARG, cmd->arg);
GOLDFISH_MMC_WRITE(host, MMC_CMD, cmdreg);
}
static void goldfish_mmc_xfer_done(struct goldfish_mmc_host *host,
struct mmc_data *data)
{
if (host->dma_in_use) {
enum dma_data_direction dma_data_dir;
if (data->flags & MMC_DATA_WRITE)
dma_data_dir = DMA_TO_DEVICE;
else
dma_data_dir = DMA_FROM_DEVICE;
if (dma_data_dir == DMA_FROM_DEVICE) {
/*
* We don't really have DMA, so we need
* to copy from our platform driver buffer
*/
uint8_t *dest = (uint8_t *)sg_virt(data->sg);
memcpy(dest, host->virt_base, data->sg->length);
}
host->data->bytes_xfered += data->sg->length;
dma_unmap_sg(mmc_dev(host->mmc), data->sg, host->sg_len,
dma_data_dir);
}
host->data = NULL;
host->sg_len = 0;
/*
* NOTE: MMC layer will sometimes poll-wait CMD13 next, issuing
* dozens of requests until the card finishes writing data.
* It'd be cheaper to just wait till an EOFB interrupt arrives...
*/
if (!data->stop) {
host->mrq = NULL;
mmc_request_done(host->mmc, data->mrq);
return;
}
goldfish_mmc_start_command(host, data->stop);
}
static void goldfish_mmc_end_of_data(struct goldfish_mmc_host *host,
struct mmc_data *data)
{
if (!host->dma_in_use) {
goldfish_mmc_xfer_done(host, data);
return;
}
if (host->dma_done)
goldfish_mmc_xfer_done(host, data);
}
static void goldfish_mmc_cmd_done(struct goldfish_mmc_host *host,
struct mmc_command *cmd)
{
host->cmd = NULL;
if (cmd->flags & MMC_RSP_PRESENT) {
if (cmd->flags & MMC_RSP_136) {
/* response type 2 */
cmd->resp[3] =
GOLDFISH_MMC_READ(host, MMC_RESP_0);
cmd->resp[2] =
GOLDFISH_MMC_READ(host, MMC_RESP_1);
cmd->resp[1] =
GOLDFISH_MMC_READ(host, MMC_RESP_2);
cmd->resp[0] =
GOLDFISH_MMC_READ(host, MMC_RESP_3);
} else {
/* response types 1, 1b, 3, 4, 5, 6 */
cmd->resp[0] =
GOLDFISH_MMC_READ(host, MMC_RESP_0);
}
}
if (host->data == NULL || cmd->error) {
host->mrq = NULL;
mmc_request_done(host->mmc, cmd->mrq);
}
}
static irqreturn_t goldfish_mmc_irq(int irq, void *dev_id)
{
struct goldfish_mmc_host *host = (struct goldfish_mmc_host *)dev_id;
u16 status;
int end_command = 0;
int end_transfer = 0;
int transfer_error = 0;
int state_changed = 0;
int cmd_timeout = 0;
while ((status = GOLDFISH_MMC_READ(host, MMC_INT_STATUS)) != 0) {
GOLDFISH_MMC_WRITE(host, MMC_INT_STATUS, status);
if (status & MMC_STAT_END_OF_CMD)
end_command = 1;
if (status & MMC_STAT_END_OF_DATA)
end_transfer = 1;
if (status & MMC_STAT_STATE_CHANGE)
state_changed = 1;
if (status & MMC_STAT_CMD_TIMEOUT) {
end_command = 0;
cmd_timeout = 1;
}
}
if (cmd_timeout) {
struct mmc_request *mrq = host->mrq;
mrq->cmd->error = -ETIMEDOUT;
host->mrq = NULL;
mmc_request_done(host->mmc, mrq);
}
if (end_command)
goldfish_mmc_cmd_done(host, host->cmd);
if (transfer_error)
goldfish_mmc_xfer_done(host, host->data);
else if (end_transfer) {
host->dma_done = 1;
goldfish_mmc_end_of_data(host, host->data);
} else if (host->data != NULL) {
/*
* WORKAROUND -- after porting this driver from 2.6 to 3.4,
* during device initialization, cases where host->data is
* non-null but end_transfer is false would occur. Doing
* nothing in such cases results in no further interrupts,
* and initialization failure.
* TODO -- find the real cause.
*/
host->dma_done = 1;
goldfish_mmc_end_of_data(host, host->data);
}
if (state_changed) {
u32 state = GOLDFISH_MMC_READ(host, MMC_STATE);
pr_info("%s: Card detect now %d\n", __func__,
(state & MMC_STATE_INSERTED));
mmc_detect_change(host->mmc, 0);
}
if (!end_command && !end_transfer &&
!transfer_error && !state_changed && !cmd_timeout) {
status = GOLDFISH_MMC_READ(host, MMC_INT_STATUS);
dev_info(mmc_dev(host->mmc),"spurious irq 0x%04x\n", status);
if (status != 0) {
GOLDFISH_MMC_WRITE(host, MMC_INT_STATUS, status);
GOLDFISH_MMC_WRITE(host, MMC_INT_ENABLE, 0);
}
}
return IRQ_HANDLED;
}
static void goldfish_mmc_prepare_data(struct goldfish_mmc_host *host,
struct mmc_request *req)
{
struct mmc_data *data = req->data;
int block_size;
unsigned sg_len;
enum dma_data_direction dma_data_dir;
host->data = data;
if (data == NULL) {
GOLDFISH_MMC_WRITE(host, MMC_BLOCK_LENGTH, 0);
GOLDFISH_MMC_WRITE(host, MMC_BLOCK_COUNT, 0);
host->dma_in_use = 0;
return;
}
block_size = data->blksz;
GOLDFISH_MMC_WRITE(host, MMC_BLOCK_COUNT, data->blocks - 1);
GOLDFISH_MMC_WRITE(host, MMC_BLOCK_LENGTH, block_size - 1);
/*
* Cope with calling layer confusion; it issues "single
* block" writes using multi-block scatterlists.
*/
sg_len = (data->blocks == 1) ? 1 : data->sg_len;
if (data->flags & MMC_DATA_WRITE)
dma_data_dir = DMA_TO_DEVICE;
else
dma_data_dir = DMA_FROM_DEVICE;
host->sg_len = dma_map_sg(mmc_dev(host->mmc), data->sg,
sg_len, dma_data_dir);
host->dma_done = 0;
host->dma_in_use = 1;
if (dma_data_dir == DMA_TO_DEVICE) {
/*
* We don't really have DMA, so we need to copy to our
* platform driver buffer
*/
const uint8_t *src = (uint8_t *)sg_virt(data->sg);
memcpy(host->virt_base, src, data->sg->length);
}
}
static void goldfish_mmc_request(struct mmc_host *mmc, struct mmc_request *req)
{
struct goldfish_mmc_host *host = mmc_priv(mmc);
WARN_ON(host->mrq != NULL);
host->mrq = req;
goldfish_mmc_prepare_data(host, req);
goldfish_mmc_start_command(host, req->cmd);
/*
* This is to avoid accidentally being detected as an SDIO card
* in mmc_attach_sdio().
*/
if (req->cmd->opcode == SD_IO_SEND_OP_COND &&
req->cmd->flags == (MMC_RSP_SPI_R4 | MMC_RSP_R4 | MMC_CMD_BCR))
req->cmd->error = -EINVAL;
}
static void goldfish_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
{
struct goldfish_mmc_host *host = mmc_priv(mmc);
host->bus_mode = ios->bus_mode;
host->hw_bus_mode = host->bus_mode;
}
static int goldfish_mmc_get_ro(struct mmc_host *mmc)
{
uint32_t state;
struct goldfish_mmc_host *host = mmc_priv(mmc);
state = GOLDFISH_MMC_READ(host, MMC_STATE);
return ((state & MMC_STATE_READ_ONLY) != 0);
}
static const struct mmc_host_ops goldfish_mmc_ops = {
.request = goldfish_mmc_request,
.set_ios = goldfish_mmc_set_ios,
.get_ro = goldfish_mmc_get_ro,
};
static int goldfish_mmc_probe(struct platform_device *pdev)
{
struct mmc_host *mmc;
struct goldfish_mmc_host *host = NULL;
struct resource *res;
int ret = 0;
int irq;
dma_addr_t buf_addr;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
irq = platform_get_irq(pdev, 0);
if (res == NULL || irq < 0)
return -ENXIO;
mmc = mmc_alloc_host(sizeof(struct goldfish_mmc_host), &pdev->dev);
if (mmc == NULL) {
ret = -ENOMEM;
goto err_alloc_host_failed;
}
host = mmc_priv(mmc);
host->mmc = mmc;
pr_err("mmc: Mapping %lX to %lX\n", (long)res->start, (long)res->end);
host->reg_base = ioremap(res->start, resource_size(res));
if (host->reg_base == NULL) {
ret = -ENOMEM;
goto ioremap_failed;
}
host->virt_base = dma_alloc_coherent(&pdev->dev, BUFFER_SIZE,
&buf_addr, GFP_KERNEL);
if (host->virt_base == 0) {
ret = -ENOMEM;
goto dma_alloc_failed;
}
host->phys_base = buf_addr;
host->id = pdev->id;
host->irq = irq;
mmc->ops = &goldfish_mmc_ops;
mmc->f_min = 400000;
mmc->f_max = 24000000;
mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
mmc->caps = MMC_CAP_4_BIT_DATA;
/* Use scatterlist DMA to reduce per-transfer costs.
* NOTE max_seg_size assumption that small blocks aren't
* normally used (except e.g. for reading SD registers).
*/
mmc->max_segs = 32;
mmc->max_blk_size = 2048; /* MMC_BLOCK_LENGTH is 11 bits (+1) */
mmc->max_blk_count = 2048; /* MMC_BLOCK_COUNT is 11 bits (+1) */
mmc->max_req_size = BUFFER_SIZE;
mmc->max_seg_size = mmc->max_req_size;
ret = request_irq(host->irq, goldfish_mmc_irq, 0, DRIVER_NAME, host);
if (ret) {
dev_err(&pdev->dev, "Failed IRQ Adding goldfish MMC\n");
goto err_request_irq_failed;
}
host->dev = &pdev->dev;
platform_set_drvdata(pdev, host);
ret = device_create_file(&pdev->dev, &dev_attr_cover_switch);
if (ret)
dev_warn(mmc_dev(host->mmc),
"Unable to create sysfs attributes\n");
GOLDFISH_MMC_WRITE(host, MMC_SET_BUFFER, host->phys_base);
GOLDFISH_MMC_WRITE(host, MMC_INT_ENABLE,
MMC_STAT_END_OF_CMD | MMC_STAT_END_OF_DATA |
MMC_STAT_STATE_CHANGE | MMC_STAT_CMD_TIMEOUT);
mmc_add_host(mmc);
return 0;
err_request_irq_failed:
dma_free_coherent(&pdev->dev, BUFFER_SIZE, host->virt_base,
host->phys_base);
dma_alloc_failed:
iounmap(host->reg_base);
ioremap_failed:
mmc_free_host(host->mmc);
err_alloc_host_failed:
return ret;
}
static int goldfish_mmc_remove(struct platform_device *pdev)
{
struct goldfish_mmc_host *host = platform_get_drvdata(pdev);
BUG_ON(host == NULL);
mmc_remove_host(host->mmc);
free_irq(host->irq, host);
dma_free_coherent(&pdev->dev, BUFFER_SIZE, host->virt_base, host->phys_base);
iounmap(host->reg_base);
mmc_free_host(host->mmc);
return 0;
}
static struct platform_driver goldfish_mmc_driver = {
.probe = goldfish_mmc_probe,
.remove = goldfish_mmc_remove,
.driver = {
.name = DRIVER_NAME,
},
};
module_platform_driver(goldfish_mmc_driver);
MODULE_LICENSE("GPL v2");