linux/drivers/mmc/host/alcor.c
Colin Ian King 42248a918d mmc: alcor: remove a redundant greater or equal to zero comparison
A greater or equal comparison on the unsigned int variable tmp_diff
is always true as unsigned ints are never negative.  Hence the
comparison is redundant and can be removed.

Addresses-Coverity: ("Unsigned compared against 0")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2019-07-10 13:17:30 +02:00

1185 lines
29 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2018 Oleksij Rempel <linux@rempel-privat.de>
*
* Driver for Alcor Micro AU6601 and AU6621 controllers
*/
/* Note: this driver was created without any documentation. Based
* on sniffing, testing and in some cases mimic of original driver.
* As soon as some one with documentation or more experience in SD/MMC, or
* reverse engineering then me, please review this driver and question every
* thing what I did. 2018 Oleksij Rempel <linux@rempel-privat.de>
*/
#include <linux/delay.h>
#include <linux/pci.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/pm.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/mmc/host.h>
#include <linux/mmc/mmc.h>
#include <linux/alcor_pci.h>
enum alcor_cookie {
COOKIE_UNMAPPED,
COOKIE_PRE_MAPPED,
COOKIE_MAPPED,
};
struct alcor_pll_conf {
unsigned int clk_src_freq;
unsigned int clk_src_reg;
unsigned int min_div;
unsigned int max_div;
};
struct alcor_sdmmc_host {
struct device *dev;
struct alcor_pci_priv *alcor_pci;
struct mmc_request *mrq;
struct mmc_command *cmd;
struct mmc_data *data;
unsigned int dma_on:1;
struct mutex cmd_mutex;
struct delayed_work timeout_work;
struct sg_mapping_iter sg_miter; /* SG state for PIO */
struct scatterlist *sg;
unsigned int blocks; /* remaining PIO blocks */
int sg_count;
u32 irq_status_sd;
unsigned char cur_power_mode;
};
static const struct alcor_pll_conf alcor_pll_cfg[] = {
/* MHZ, CLK src, max div, min div */
{ 31250000, AU6601_CLK_31_25_MHZ, 1, 511},
{ 48000000, AU6601_CLK_48_MHZ, 1, 511},
{125000000, AU6601_CLK_125_MHZ, 1, 511},
{384000000, AU6601_CLK_384_MHZ, 1, 511},
};
static inline void alcor_rmw8(struct alcor_sdmmc_host *host, unsigned int addr,
u8 clear, u8 set)
{
struct alcor_pci_priv *priv = host->alcor_pci;
u32 var;
var = alcor_read8(priv, addr);
var &= ~clear;
var |= set;
alcor_write8(priv, var, addr);
}
/* As soon as irqs are masked, some status updates may be missed.
* Use this with care.
*/
static inline void alcor_mask_sd_irqs(struct alcor_sdmmc_host *host)
{
struct alcor_pci_priv *priv = host->alcor_pci;
alcor_write32(priv, 0, AU6601_REG_INT_ENABLE);
}
static inline void alcor_unmask_sd_irqs(struct alcor_sdmmc_host *host)
{
struct alcor_pci_priv *priv = host->alcor_pci;
alcor_write32(priv, AU6601_INT_CMD_MASK | AU6601_INT_DATA_MASK |
AU6601_INT_CARD_INSERT | AU6601_INT_CARD_REMOVE |
AU6601_INT_OVER_CURRENT_ERR,
AU6601_REG_INT_ENABLE);
}
static void alcor_reset(struct alcor_sdmmc_host *host, u8 val)
{
struct alcor_pci_priv *priv = host->alcor_pci;
int i;
alcor_write8(priv, val | AU6601_BUF_CTRL_RESET,
AU6601_REG_SW_RESET);
for (i = 0; i < 100; i++) {
if (!(alcor_read8(priv, AU6601_REG_SW_RESET) & val))
return;
udelay(50);
}
dev_err(host->dev, "%s: timeout\n", __func__);
}
/*
* Perform DMA I/O of a single page.
*/
static void alcor_data_set_dma(struct alcor_sdmmc_host *host)
{
struct alcor_pci_priv *priv = host->alcor_pci;
u32 addr;
if (!host->sg_count)
return;
if (!host->sg) {
dev_err(host->dev, "have blocks, but no SG\n");
return;
}
if (!sg_dma_len(host->sg)) {
dev_err(host->dev, "DMA SG len == 0\n");
return;
}
addr = (u32)sg_dma_address(host->sg);
alcor_write32(priv, addr, AU6601_REG_SDMA_ADDR);
host->sg = sg_next(host->sg);
host->sg_count--;
}
static void alcor_trigger_data_transfer(struct alcor_sdmmc_host *host)
{
struct alcor_pci_priv *priv = host->alcor_pci;
struct mmc_data *data = host->data;
u8 ctrl = 0;
if (data->flags & MMC_DATA_WRITE)
ctrl |= AU6601_DATA_WRITE;
if (data->host_cookie == COOKIE_MAPPED) {
/*
* For DMA transfers, this function is called just once,
* at the start of the operation. The hardware can only
* perform DMA I/O on a single page at a time, so here
* we kick off the transfer with the first page, and expect
* subsequent pages to be transferred upon IRQ events
* indicating that the single-page DMA was completed.
*/
alcor_data_set_dma(host);
ctrl |= AU6601_DATA_DMA_MODE;
host->dma_on = 1;
alcor_write32(priv, data->sg_count * 0x1000,
AU6601_REG_BLOCK_SIZE);
} else {
/*
* For PIO transfers, we break down each operation
* into several sector-sized transfers. When one sector has
* complete, the IRQ handler will call this function again
* to kick off the transfer of the next sector.
*/
alcor_write32(priv, data->blksz, AU6601_REG_BLOCK_SIZE);
}
alcor_write8(priv, ctrl | AU6601_DATA_START_XFER,
AU6601_DATA_XFER_CTRL);
}
static void alcor_trf_block_pio(struct alcor_sdmmc_host *host, bool read)
{
struct alcor_pci_priv *priv = host->alcor_pci;
size_t blksize, len;
u8 *buf;
if (!host->blocks)
return;
if (host->dma_on) {
dev_err(host->dev, "configured DMA but got PIO request.\n");
return;
}
if (!!(host->data->flags & MMC_DATA_READ) != read) {
dev_err(host->dev, "got unexpected direction %i != %i\n",
!!(host->data->flags & MMC_DATA_READ), read);
}
if (!sg_miter_next(&host->sg_miter))
return;
blksize = host->data->blksz;
len = min(host->sg_miter.length, blksize);
dev_dbg(host->dev, "PIO, %s block size: 0x%zx\n",
read ? "read" : "write", blksize);
host->sg_miter.consumed = len;
host->blocks--;
buf = host->sg_miter.addr;
if (read)
ioread32_rep(priv->iobase + AU6601_REG_BUFFER, buf, len >> 2);
else
iowrite32_rep(priv->iobase + AU6601_REG_BUFFER, buf, len >> 2);
sg_miter_stop(&host->sg_miter);
}
static void alcor_prepare_sg_miter(struct alcor_sdmmc_host *host)
{
unsigned int flags = SG_MITER_ATOMIC;
struct mmc_data *data = host->data;
if (data->flags & MMC_DATA_READ)
flags |= SG_MITER_TO_SG;
else
flags |= SG_MITER_FROM_SG;
sg_miter_start(&host->sg_miter, data->sg, data->sg_len, flags);
}
static void alcor_prepare_data(struct alcor_sdmmc_host *host,
struct mmc_command *cmd)
{
struct alcor_pci_priv *priv = host->alcor_pci;
struct mmc_data *data = cmd->data;
if (!data)
return;
host->data = data;
host->data->bytes_xfered = 0;
host->blocks = data->blocks;
host->sg = data->sg;
host->sg_count = data->sg_count;
dev_dbg(host->dev, "prepare DATA: sg %i, blocks: %i\n",
host->sg_count, host->blocks);
if (data->host_cookie != COOKIE_MAPPED)
alcor_prepare_sg_miter(host);
alcor_write8(priv, 0, AU6601_DATA_XFER_CTRL);
}
static void alcor_send_cmd(struct alcor_sdmmc_host *host,
struct mmc_command *cmd, bool set_timeout)
{
struct alcor_pci_priv *priv = host->alcor_pci;
unsigned long timeout = 0;
u8 ctrl = 0;
host->cmd = cmd;
alcor_prepare_data(host, cmd);
dev_dbg(host->dev, "send CMD. opcode: 0x%02x, arg; 0x%08x\n",
cmd->opcode, cmd->arg);
alcor_write8(priv, cmd->opcode | 0x40, AU6601_REG_CMD_OPCODE);
alcor_write32be(priv, cmd->arg, AU6601_REG_CMD_ARG);
switch (mmc_resp_type(cmd)) {
case MMC_RSP_NONE:
ctrl = AU6601_CMD_NO_RESP;
break;
case MMC_RSP_R1:
ctrl = AU6601_CMD_6_BYTE_CRC;
break;
case MMC_RSP_R1B:
ctrl = AU6601_CMD_6_BYTE_CRC | AU6601_CMD_STOP_WAIT_RDY;
break;
case MMC_RSP_R2:
ctrl = AU6601_CMD_17_BYTE_CRC;
break;
case MMC_RSP_R3:
ctrl = AU6601_CMD_6_BYTE_WO_CRC;
break;
default:
dev_err(host->dev, "%s: cmd->flag (0x%02x) is not valid\n",
mmc_hostname(mmc_from_priv(host)), mmc_resp_type(cmd));
break;
}
if (set_timeout) {
if (!cmd->data && cmd->busy_timeout)
timeout = cmd->busy_timeout;
else
timeout = 10000;
schedule_delayed_work(&host->timeout_work,
msecs_to_jiffies(timeout));
}
dev_dbg(host->dev, "xfer ctrl: 0x%02x; timeout: %lu\n", ctrl, timeout);
alcor_write8(priv, ctrl | AU6601_CMD_START_XFER,
AU6601_CMD_XFER_CTRL);
}
static void alcor_request_complete(struct alcor_sdmmc_host *host,
bool cancel_timeout)
{
struct mmc_request *mrq;
/*
* If this work gets rescheduled while running, it will
* be run again afterwards but without any active request.
*/
if (!host->mrq)
return;
if (cancel_timeout)
cancel_delayed_work(&host->timeout_work);
mrq = host->mrq;
host->mrq = NULL;
host->cmd = NULL;
host->data = NULL;
host->dma_on = 0;
mmc_request_done(mmc_from_priv(host), mrq);
}
static void alcor_finish_data(struct alcor_sdmmc_host *host)
{
struct mmc_data *data;
data = host->data;
host->data = NULL;
host->dma_on = 0;
/*
* The specification states that the block count register must
* be updated, but it does not specify at what point in the
* data flow. That makes the register entirely useless to read
* back so we have to assume that nothing made it to the card
* in the event of an error.
*/
if (data->error)
data->bytes_xfered = 0;
else
data->bytes_xfered = data->blksz * data->blocks;
/*
* Need to send CMD12 if -
* a) open-ended multiblock transfer (no CMD23)
* b) error in multiblock transfer
*/
if (data->stop &&
(data->error ||
!host->mrq->sbc)) {
/*
* The controller needs a reset of internal state machines
* upon error conditions.
*/
if (data->error)
alcor_reset(host, AU6601_RESET_CMD | AU6601_RESET_DATA);
alcor_unmask_sd_irqs(host);
alcor_send_cmd(host, data->stop, false);
return;
}
alcor_request_complete(host, 1);
}
static void alcor_err_irq(struct alcor_sdmmc_host *host, u32 intmask)
{
dev_dbg(host->dev, "ERR IRQ %x\n", intmask);
if (host->cmd) {
if (intmask & AU6601_INT_CMD_TIMEOUT_ERR)
host->cmd->error = -ETIMEDOUT;
else
host->cmd->error = -EILSEQ;
}
if (host->data) {
if (intmask & AU6601_INT_DATA_TIMEOUT_ERR)
host->data->error = -ETIMEDOUT;
else
host->data->error = -EILSEQ;
host->data->bytes_xfered = 0;
}
alcor_reset(host, AU6601_RESET_CMD | AU6601_RESET_DATA);
alcor_request_complete(host, 1);
}
static int alcor_cmd_irq_done(struct alcor_sdmmc_host *host, u32 intmask)
{
struct alcor_pci_priv *priv = host->alcor_pci;
intmask &= AU6601_INT_CMD_END;
if (!intmask)
return true;
/* got CMD_END but no CMD is in progress, wake thread an process the
* error
*/
if (!host->cmd)
return false;
if (host->cmd->flags & MMC_RSP_PRESENT) {
struct mmc_command *cmd = host->cmd;
cmd->resp[0] = alcor_read32be(priv, AU6601_REG_CMD_RSP0);
dev_dbg(host->dev, "RSP0: 0x%04x\n", cmd->resp[0]);
if (host->cmd->flags & MMC_RSP_136) {
cmd->resp[1] =
alcor_read32be(priv, AU6601_REG_CMD_RSP1);
cmd->resp[2] =
alcor_read32be(priv, AU6601_REG_CMD_RSP2);
cmd->resp[3] =
alcor_read32be(priv, AU6601_REG_CMD_RSP3);
dev_dbg(host->dev, "RSP1,2,3: 0x%04x 0x%04x 0x%04x\n",
cmd->resp[1], cmd->resp[2], cmd->resp[3]);
}
}
host->cmd->error = 0;
/* Processed actual command. */
if (!host->data)
return false;
alcor_trigger_data_transfer(host);
host->cmd = NULL;
return true;
}
static void alcor_cmd_irq_thread(struct alcor_sdmmc_host *host, u32 intmask)
{
intmask &= AU6601_INT_CMD_END;
if (!intmask)
return;
if (!host->cmd && intmask & AU6601_INT_CMD_END) {
dev_dbg(host->dev, "Got command interrupt 0x%08x even though no command operation was in progress.\n",
intmask);
}
/* Processed actual command. */
if (!host->data)
alcor_request_complete(host, 1);
else
alcor_trigger_data_transfer(host);
host->cmd = NULL;
}
static int alcor_data_irq_done(struct alcor_sdmmc_host *host, u32 intmask)
{
u32 tmp;
intmask &= AU6601_INT_DATA_MASK;
/* nothing here to do */
if (!intmask)
return 1;
/* we was too fast and got DATA_END after it was processed?
* lets ignore it for now.
*/
if (!host->data && intmask == AU6601_INT_DATA_END)
return 1;
/* looks like an error, so lets handle it. */
if (!host->data)
return 0;
tmp = intmask & (AU6601_INT_READ_BUF_RDY | AU6601_INT_WRITE_BUF_RDY
| AU6601_INT_DMA_END);
switch (tmp) {
case 0:
break;
case AU6601_INT_READ_BUF_RDY:
alcor_trf_block_pio(host, true);
return 1;
case AU6601_INT_WRITE_BUF_RDY:
alcor_trf_block_pio(host, false);
return 1;
case AU6601_INT_DMA_END:
if (!host->sg_count)
break;
alcor_data_set_dma(host);
break;
default:
dev_err(host->dev, "Got READ_BUF_RDY and WRITE_BUF_RDY at same time\n");
break;
}
if (intmask & AU6601_INT_DATA_END) {
if (!host->dma_on && host->blocks) {
alcor_trigger_data_transfer(host);
return 1;
} else {
return 0;
}
}
return 1;
}
static void alcor_data_irq_thread(struct alcor_sdmmc_host *host, u32 intmask)
{
intmask &= AU6601_INT_DATA_MASK;
if (!intmask)
return;
if (!host->data) {
dev_dbg(host->dev, "Got data interrupt 0x%08x even though no data operation was in progress.\n",
intmask);
alcor_reset(host, AU6601_RESET_DATA);
return;
}
if (alcor_data_irq_done(host, intmask))
return;
if ((intmask & AU6601_INT_DATA_END) || !host->blocks ||
(host->dma_on && !host->sg_count))
alcor_finish_data(host);
}
static void alcor_cd_irq(struct alcor_sdmmc_host *host, u32 intmask)
{
dev_dbg(host->dev, "card %s\n",
intmask & AU6601_INT_CARD_REMOVE ? "removed" : "inserted");
if (host->mrq) {
dev_dbg(host->dev, "cancel all pending tasks.\n");
if (host->data)
host->data->error = -ENOMEDIUM;
if (host->cmd)
host->cmd->error = -ENOMEDIUM;
else
host->mrq->cmd->error = -ENOMEDIUM;
alcor_request_complete(host, 1);
}
mmc_detect_change(mmc_from_priv(host), msecs_to_jiffies(1));
}
static irqreturn_t alcor_irq_thread(int irq, void *d)
{
struct alcor_sdmmc_host *host = d;
irqreturn_t ret = IRQ_HANDLED;
u32 intmask, tmp;
mutex_lock(&host->cmd_mutex);
intmask = host->irq_status_sd;
/* some thing bad */
if (unlikely(!intmask || AU6601_INT_ALL_MASK == intmask)) {
dev_dbg(host->dev, "unexpected IRQ: 0x%04x\n", intmask);
ret = IRQ_NONE;
goto exit;
}
tmp = intmask & (AU6601_INT_CMD_MASK | AU6601_INT_DATA_MASK);
if (tmp) {
if (tmp & AU6601_INT_ERROR_MASK)
alcor_err_irq(host, tmp);
else {
alcor_cmd_irq_thread(host, tmp);
alcor_data_irq_thread(host, tmp);
}
intmask &= ~(AU6601_INT_CMD_MASK | AU6601_INT_DATA_MASK);
}
if (intmask & (AU6601_INT_CARD_INSERT | AU6601_INT_CARD_REMOVE)) {
alcor_cd_irq(host, intmask);
intmask &= ~(AU6601_INT_CARD_INSERT | AU6601_INT_CARD_REMOVE);
}
if (intmask & AU6601_INT_OVER_CURRENT_ERR) {
dev_warn(host->dev,
"warning: over current detected!\n");
intmask &= ~AU6601_INT_OVER_CURRENT_ERR;
}
if (intmask)
dev_dbg(host->dev, "got not handled IRQ: 0x%04x\n", intmask);
exit:
mutex_unlock(&host->cmd_mutex);
alcor_unmask_sd_irqs(host);
return ret;
}
static irqreturn_t alcor_irq(int irq, void *d)
{
struct alcor_sdmmc_host *host = d;
struct alcor_pci_priv *priv = host->alcor_pci;
u32 status, tmp;
irqreturn_t ret;
int cmd_done, data_done;
status = alcor_read32(priv, AU6601_REG_INT_STATUS);
if (!status)
return IRQ_NONE;
alcor_write32(priv, status, AU6601_REG_INT_STATUS);
tmp = status & (AU6601_INT_READ_BUF_RDY | AU6601_INT_WRITE_BUF_RDY
| AU6601_INT_DATA_END | AU6601_INT_DMA_END
| AU6601_INT_CMD_END);
if (tmp == status) {
cmd_done = alcor_cmd_irq_done(host, tmp);
data_done = alcor_data_irq_done(host, tmp);
/* use fast path for simple tasks */
if (cmd_done && data_done) {
ret = IRQ_HANDLED;
goto alcor_irq_done;
}
}
host->irq_status_sd = status;
ret = IRQ_WAKE_THREAD;
alcor_mask_sd_irqs(host);
alcor_irq_done:
return ret;
}
static void alcor_set_clock(struct alcor_sdmmc_host *host, unsigned int clock)
{
struct alcor_pci_priv *priv = host->alcor_pci;
int i, diff = 0x7fffffff, tmp_clock = 0;
u16 clk_src = 0;
u8 clk_div = 0;
if (clock == 0) {
alcor_write16(priv, 0, AU6601_CLK_SELECT);
return;
}
for (i = 0; i < ARRAY_SIZE(alcor_pll_cfg); i++) {
unsigned int tmp_div, tmp_diff;
const struct alcor_pll_conf *cfg = &alcor_pll_cfg[i];
tmp_div = DIV_ROUND_UP(cfg->clk_src_freq, clock);
if (cfg->min_div > tmp_div || tmp_div > cfg->max_div)
continue;
tmp_clock = DIV_ROUND_UP(cfg->clk_src_freq, tmp_div);
tmp_diff = abs(clock - tmp_clock);
if (tmp_diff < diff) {
diff = tmp_diff;
clk_src = cfg->clk_src_reg;
clk_div = tmp_div;
}
}
clk_src |= ((clk_div - 1) << 8);
clk_src |= AU6601_CLK_ENABLE;
dev_dbg(host->dev, "set freq %d cal freq %d, use div %d, mod %x\n",
clock, tmp_clock, clk_div, clk_src);
alcor_write16(priv, clk_src, AU6601_CLK_SELECT);
}
static void alcor_set_timing(struct mmc_host *mmc, struct mmc_ios *ios)
{
struct alcor_sdmmc_host *host = mmc_priv(mmc);
if (ios->timing == MMC_TIMING_LEGACY) {
alcor_rmw8(host, AU6601_CLK_DELAY,
AU6601_CLK_POSITIVE_EDGE_ALL, 0);
} else {
alcor_rmw8(host, AU6601_CLK_DELAY,
0, AU6601_CLK_POSITIVE_EDGE_ALL);
}
}
static void alcor_set_bus_width(struct mmc_host *mmc, struct mmc_ios *ios)
{
struct alcor_sdmmc_host *host = mmc_priv(mmc);
struct alcor_pci_priv *priv = host->alcor_pci;
if (ios->bus_width == MMC_BUS_WIDTH_1) {
alcor_write8(priv, 0, AU6601_REG_BUS_CTRL);
} else if (ios->bus_width == MMC_BUS_WIDTH_4) {
alcor_write8(priv, AU6601_BUS_WIDTH_4BIT,
AU6601_REG_BUS_CTRL);
} else
dev_err(host->dev, "Unknown BUS mode\n");
}
static int alcor_card_busy(struct mmc_host *mmc)
{
struct alcor_sdmmc_host *host = mmc_priv(mmc);
struct alcor_pci_priv *priv = host->alcor_pci;
u8 status;
/* Check whether dat[0:3] low */
status = alcor_read8(priv, AU6601_DATA_PIN_STATE);
return !(status & AU6601_BUS_STAT_DAT_MASK);
}
static int alcor_get_cd(struct mmc_host *mmc)
{
struct alcor_sdmmc_host *host = mmc_priv(mmc);
struct alcor_pci_priv *priv = host->alcor_pci;
u8 detect;
detect = alcor_read8(priv, AU6601_DETECT_STATUS)
& AU6601_DETECT_STATUS_M;
/* check if card is present then send command and data */
return (detect == AU6601_SD_DETECTED);
}
static int alcor_get_ro(struct mmc_host *mmc)
{
struct alcor_sdmmc_host *host = mmc_priv(mmc);
struct alcor_pci_priv *priv = host->alcor_pci;
u8 status;
/* get write protect pin status */
status = alcor_read8(priv, AU6601_INTERFACE_MODE_CTRL);
return !!(status & AU6601_SD_CARD_WP);
}
static void alcor_request(struct mmc_host *mmc, struct mmc_request *mrq)
{
struct alcor_sdmmc_host *host = mmc_priv(mmc);
mutex_lock(&host->cmd_mutex);
host->mrq = mrq;
/* check if card is present then send command and data */
if (alcor_get_cd(mmc))
alcor_send_cmd(host, mrq->cmd, true);
else {
mrq->cmd->error = -ENOMEDIUM;
alcor_request_complete(host, 1);
}
mutex_unlock(&host->cmd_mutex);
}
static void alcor_pre_req(struct mmc_host *mmc,
struct mmc_request *mrq)
{
struct alcor_sdmmc_host *host = mmc_priv(mmc);
struct mmc_data *data = mrq->data;
struct mmc_command *cmd = mrq->cmd;
struct scatterlist *sg;
unsigned int i, sg_len;
if (!data || !cmd)
return;
data->host_cookie = COOKIE_UNMAPPED;
/* FIXME: looks like the DMA engine works only with CMD18 */
if (cmd->opcode != MMC_READ_MULTIPLE_BLOCK
&& cmd->opcode != MMC_WRITE_MULTIPLE_BLOCK)
return;
/*
* We don't do DMA on "complex" transfers, i.e. with
* non-word-aligned buffers or lengths. A future improvement
* could be made to use temporary DMA bounce-buffers when these
* requirements are not met.
*
* Also, we don't bother with all the DMA setup overhead for
* short transfers.
*/
if (data->blocks * data->blksz < AU6601_MAX_DMA_BLOCK_SIZE)
return;
if (data->blksz & 3)
return;
for_each_sg(data->sg, sg, data->sg_len, i) {
if (sg->length != AU6601_MAX_DMA_BLOCK_SIZE)
return;
if (sg->offset != 0)
return;
}
/* This data might be unmapped at this time */
sg_len = dma_map_sg(host->dev, data->sg, data->sg_len,
mmc_get_dma_dir(data));
if (sg_len)
data->host_cookie = COOKIE_MAPPED;
data->sg_count = sg_len;
}
static void alcor_post_req(struct mmc_host *mmc,
struct mmc_request *mrq,
int err)
{
struct alcor_sdmmc_host *host = mmc_priv(mmc);
struct mmc_data *data = mrq->data;
if (!data)
return;
if (data->host_cookie == COOKIE_MAPPED) {
dma_unmap_sg(host->dev,
data->sg,
data->sg_len,
mmc_get_dma_dir(data));
}
data->host_cookie = COOKIE_UNMAPPED;
}
static void alcor_set_power_mode(struct mmc_host *mmc, struct mmc_ios *ios)
{
struct alcor_sdmmc_host *host = mmc_priv(mmc);
struct alcor_pci_priv *priv = host->alcor_pci;
switch (ios->power_mode) {
case MMC_POWER_OFF:
alcor_set_clock(host, ios->clock);
/* set all pins to input */
alcor_write8(priv, 0, AU6601_OUTPUT_ENABLE);
/* turn of VDD */
alcor_write8(priv, 0, AU6601_POWER_CONTROL);
break;
case MMC_POWER_UP:
break;
case MMC_POWER_ON:
/* This is most trickiest part. The order and timings of
* instructions seems to play important role. Any changes may
* confuse internal state engine if this HW.
* FIXME: If we will ever get access to documentation, then this
* part should be reviewed again.
*/
/* enable SD card mode */
alcor_write8(priv, AU6601_SD_CARD,
AU6601_ACTIVE_CTRL);
/* set signal voltage to 3.3V */
alcor_write8(priv, 0, AU6601_OPT);
/* no documentation about clk delay, for now just try to mimic
* original driver.
*/
alcor_write8(priv, 0x20, AU6601_CLK_DELAY);
/* set BUS width to 1 bit */
alcor_write8(priv, 0, AU6601_REG_BUS_CTRL);
/* set CLK first time */
alcor_set_clock(host, ios->clock);
/* power on VDD */
alcor_write8(priv, AU6601_SD_CARD,
AU6601_POWER_CONTROL);
/* wait until the CLK will get stable */
mdelay(20);
/* set CLK again, mimic original driver. */
alcor_set_clock(host, ios->clock);
/* enable output */
alcor_write8(priv, AU6601_SD_CARD,
AU6601_OUTPUT_ENABLE);
/* The clk will not work on au6621. We need to trigger data
* transfer.
*/
alcor_write8(priv, AU6601_DATA_WRITE,
AU6601_DATA_XFER_CTRL);
/* configure timeout. Not clear what exactly it means. */
alcor_write8(priv, 0x7d, AU6601_TIME_OUT_CTRL);
mdelay(100);
break;
default:
dev_err(host->dev, "Unknown power parameter\n");
}
}
static void alcor_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
{
struct alcor_sdmmc_host *host = mmc_priv(mmc);
mutex_lock(&host->cmd_mutex);
dev_dbg(host->dev, "set ios. bus width: %x, power mode: %x\n",
ios->bus_width, ios->power_mode);
if (ios->power_mode != host->cur_power_mode) {
alcor_set_power_mode(mmc, ios);
host->cur_power_mode = ios->power_mode;
} else {
alcor_set_timing(mmc, ios);
alcor_set_bus_width(mmc, ios);
alcor_set_clock(host, ios->clock);
}
mutex_unlock(&host->cmd_mutex);
}
static int alcor_signal_voltage_switch(struct mmc_host *mmc,
struct mmc_ios *ios)
{
struct alcor_sdmmc_host *host = mmc_priv(mmc);
mutex_lock(&host->cmd_mutex);
switch (ios->signal_voltage) {
case MMC_SIGNAL_VOLTAGE_330:
alcor_rmw8(host, AU6601_OPT, AU6601_OPT_SD_18V, 0);
break;
case MMC_SIGNAL_VOLTAGE_180:
alcor_rmw8(host, AU6601_OPT, 0, AU6601_OPT_SD_18V);
break;
default:
/* No signal voltage switch required */
break;
}
mutex_unlock(&host->cmd_mutex);
return 0;
}
static const struct mmc_host_ops alcor_sdc_ops = {
.card_busy = alcor_card_busy,
.get_cd = alcor_get_cd,
.get_ro = alcor_get_ro,
.post_req = alcor_post_req,
.pre_req = alcor_pre_req,
.request = alcor_request,
.set_ios = alcor_set_ios,
.start_signal_voltage_switch = alcor_signal_voltage_switch,
};
static void alcor_timeout_timer(struct work_struct *work)
{
struct delayed_work *d = to_delayed_work(work);
struct alcor_sdmmc_host *host = container_of(d, struct alcor_sdmmc_host,
timeout_work);
mutex_lock(&host->cmd_mutex);
dev_dbg(host->dev, "triggered timeout\n");
if (host->mrq) {
dev_err(host->dev, "Timeout waiting for hardware interrupt.\n");
if (host->data) {
host->data->error = -ETIMEDOUT;
} else {
if (host->cmd)
host->cmd->error = -ETIMEDOUT;
else
host->mrq->cmd->error = -ETIMEDOUT;
}
alcor_reset(host, AU6601_RESET_CMD | AU6601_RESET_DATA);
alcor_request_complete(host, 0);
}
mutex_unlock(&host->cmd_mutex);
}
static void alcor_hw_init(struct alcor_sdmmc_host *host)
{
struct alcor_pci_priv *priv = host->alcor_pci;
struct alcor_dev_cfg *cfg = priv->cfg;
/* FIXME: This part is a mimics HW init of original driver.
* If we will ever get access to documentation, then this part
* should be reviewed again.
*/
/* reset command state engine */
alcor_reset(host, AU6601_RESET_CMD);
alcor_write8(priv, 0, AU6601_DMA_BOUNDARY);
/* enable sd card mode */
alcor_write8(priv, AU6601_SD_CARD, AU6601_ACTIVE_CTRL);
/* set BUS width to 1 bit */
alcor_write8(priv, 0, AU6601_REG_BUS_CTRL);
/* reset data state engine */
alcor_reset(host, AU6601_RESET_DATA);
/* Not sure if a voodoo with AU6601_DMA_BOUNDARY is really needed */
alcor_write8(priv, 0, AU6601_DMA_BOUNDARY);
alcor_write8(priv, 0, AU6601_INTERFACE_MODE_CTRL);
/* not clear what we are doing here. */
alcor_write8(priv, 0x44, AU6601_PAD_DRIVE0);
alcor_write8(priv, 0x44, AU6601_PAD_DRIVE1);
alcor_write8(priv, 0x00, AU6601_PAD_DRIVE2);
/* for 6601 - dma_boundary; for 6621 - dma_page_cnt
* exact meaning of this register is not clear.
*/
alcor_write8(priv, cfg->dma, AU6601_DMA_BOUNDARY);
/* make sure all pins are set to input and VDD is off */
alcor_write8(priv, 0, AU6601_OUTPUT_ENABLE);
alcor_write8(priv, 0, AU6601_POWER_CONTROL);
alcor_write8(priv, AU6601_DETECT_EN, AU6601_DETECT_STATUS);
/* now we should be safe to enable IRQs */
alcor_unmask_sd_irqs(host);
}
static void alcor_hw_uninit(struct alcor_sdmmc_host *host)
{
struct alcor_pci_priv *priv = host->alcor_pci;
alcor_mask_sd_irqs(host);
alcor_reset(host, AU6601_RESET_CMD | AU6601_RESET_DATA);
alcor_write8(priv, 0, AU6601_DETECT_STATUS);
alcor_write8(priv, 0, AU6601_OUTPUT_ENABLE);
alcor_write8(priv, 0, AU6601_POWER_CONTROL);
alcor_write8(priv, 0, AU6601_OPT);
}
static void alcor_init_mmc(struct alcor_sdmmc_host *host)
{
struct mmc_host *mmc = mmc_from_priv(host);
mmc->f_min = AU6601_MIN_CLOCK;
mmc->f_max = AU6601_MAX_CLOCK;
mmc->ocr_avail = MMC_VDD_33_34;
mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SD_HIGHSPEED
| MMC_CAP_UHS_SDR12 | MMC_CAP_UHS_SDR25 | MMC_CAP_UHS_SDR50
| MMC_CAP_UHS_SDR104 | MMC_CAP_UHS_DDR50;
mmc->caps2 = MMC_CAP2_NO_SDIO;
mmc->ops = &alcor_sdc_ops;
/* The hardware does DMA data transfer of 4096 bytes to/from a single
* buffer address. Scatterlists are not supported at the hardware
* level, however we can work with them at the driver level,
* provided that each segment is exactly 4096 bytes in size.
* Upon DMA completion of a single segment (signalled via IRQ), we
* immediately proceed to transfer the next segment from the
* scatterlist.
*
* The overall request is limited to 240 sectors, matching the
* original vendor driver.
*/
mmc->max_segs = AU6601_MAX_DMA_SEGMENTS;
mmc->max_seg_size = AU6601_MAX_DMA_BLOCK_SIZE;
mmc->max_blk_count = 240;
mmc->max_req_size = mmc->max_blk_count * mmc->max_blk_size;
dma_set_max_seg_size(host->dev, mmc->max_seg_size);
}
static int alcor_pci_sdmmc_drv_probe(struct platform_device *pdev)
{
struct alcor_pci_priv *priv = pdev->dev.platform_data;
struct mmc_host *mmc;
struct alcor_sdmmc_host *host;
int ret;
mmc = mmc_alloc_host(sizeof(*host), &pdev->dev);
if (!mmc) {
dev_err(&pdev->dev, "Can't allocate MMC\n");
return -ENOMEM;
}
host = mmc_priv(mmc);
host->dev = &pdev->dev;
host->cur_power_mode = MMC_POWER_UNDEFINED;
host->alcor_pci = priv;
/* make sure irqs are disabled */
alcor_write32(priv, 0, AU6601_REG_INT_ENABLE);
alcor_write32(priv, 0, AU6601_MS_INT_ENABLE);
ret = devm_request_threaded_irq(&pdev->dev, priv->irq,
alcor_irq, alcor_irq_thread, IRQF_SHARED,
DRV_NAME_ALCOR_PCI_SDMMC, host);
if (ret) {
dev_err(&pdev->dev, "Failed to get irq for data line\n");
return ret;
}
mutex_init(&host->cmd_mutex);
INIT_DELAYED_WORK(&host->timeout_work, alcor_timeout_timer);
alcor_init_mmc(host);
alcor_hw_init(host);
dev_set_drvdata(&pdev->dev, host);
mmc_add_host(mmc);
return 0;
}
static int alcor_pci_sdmmc_drv_remove(struct platform_device *pdev)
{
struct alcor_sdmmc_host *host = dev_get_drvdata(&pdev->dev);
struct mmc_host *mmc = mmc_from_priv(host);
if (cancel_delayed_work_sync(&host->timeout_work))
alcor_request_complete(host, 0);
alcor_hw_uninit(host);
mmc_remove_host(mmc);
mmc_free_host(mmc);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int alcor_pci_sdmmc_suspend(struct device *dev)
{
struct alcor_sdmmc_host *host = dev_get_drvdata(dev);
if (cancel_delayed_work_sync(&host->timeout_work))
alcor_request_complete(host, 0);
alcor_hw_uninit(host);
return 0;
}
static int alcor_pci_sdmmc_resume(struct device *dev)
{
struct alcor_sdmmc_host *host = dev_get_drvdata(dev);
alcor_hw_init(host);
return 0;
}
#endif /* CONFIG_PM_SLEEP */
static SIMPLE_DEV_PM_OPS(alcor_mmc_pm_ops, alcor_pci_sdmmc_suspend,
alcor_pci_sdmmc_resume);
static const struct platform_device_id alcor_pci_sdmmc_ids[] = {
{
.name = DRV_NAME_ALCOR_PCI_SDMMC,
}, {
/* sentinel */
}
};
MODULE_DEVICE_TABLE(platform, alcor_pci_sdmmc_ids);
static struct platform_driver alcor_pci_sdmmc_driver = {
.probe = alcor_pci_sdmmc_drv_probe,
.remove = alcor_pci_sdmmc_drv_remove,
.id_table = alcor_pci_sdmmc_ids,
.driver = {
.name = DRV_NAME_ALCOR_PCI_SDMMC,
.pm = &alcor_mmc_pm_ops
},
};
module_platform_driver(alcor_pci_sdmmc_driver);
MODULE_AUTHOR("Oleksij Rempel <linux@rempel-privat.de>");
MODULE_DESCRIPTION("PCI driver for Alcor Micro AU6601 Secure Digital Host Controller Interface");
MODULE_LICENSE("GPL");