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spi/topcliff_pch: DMA support

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This patch enables this SPI driver works with DMA mode.

Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This commit is contained in:
Tomoya MORINAGA 2011-06-07 14:50:11 +09:00 committed by Grant Likely
parent f016aeb655
commit c37f3c2749
1 changed files with 488 additions and 106 deletions
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594
drivers/spi/spi-topcliff-pch.c
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@ -28,6 +28,9 @@
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/dmaengine.h>
#include <linux/pch_dma.h>
/* Register offsets */
#define PCH_SPCR 0x00 /* SPI control register */
#define PCH_SPBRR 0x04 /* SPI baud rate register */
@ -36,7 +39,7 @@
#define PCH_SPDRR 0x10 /* SPI read data register */
#define PCH_SSNXCR 0x18 /* SSN Expand Control Register */
#define PCH_SRST 0x1C /* SPI reset register */
#define PCH_SPI_ADDRESS_SIZE 0x20
#define PCH_ADDRESS_SIZE 0x20
#define PCH_SPSR_TFD 0x000007C0
#define PCH_SPSR_RFD 0x0000F800
@ -54,8 +57,6 @@
#define STATUS_EXITING 2
#define PCH_SLEEP_TIME 10
#define PCH_ADDRESS_SIZE 0x20
#define SSN_LOW 0x02U
#define SSN_NO_CONTROL 0x00U
#define PCH_MAX_CS 0xFF
@ -75,6 +76,7 @@
#define SPSR_TFI_BIT (1 << 0)
#define SPSR_RFI_BIT (1 << 1)
#define SPSR_FI_BIT (1 << 2)
#define SPSR_ORF_BIT (1 << 3)
#define SPBRR_SIZE_BIT (1 << 10)
#define PCH_ALL (SPCR_TFIE_BIT|SPCR_RFIE_BIT|SPCR_FIE_BIT|\
@ -83,10 +85,9 @@
#define SPCR_RFIC_FIELD 20
#define SPCR_TFIC_FIELD 16
#define SPSR_INT_BITS 0x1F
#define MASK_SPBRR_SPBR_BITS (~((1 << 10) - 1))
#define MASK_RFIC_SPCR_BITS (~(0xf << 20))
#define MASK_TFIC_SPCR_BITS (~(0xf000f << 12))
#define MASK_SPBRR_SPBR_BITS ((1 << 10) - 1)
#define MASK_RFIC_SPCR_BITS (0xf << SPCR_RFIC_FIELD)
#define MASK_TFIC_SPCR_BITS (0xf << SPCR_TFIC_FIELD)
#define PCH_CLOCK_HZ 50000000
#define PCH_MAX_SPBR 1023
@ -102,6 +103,28 @@
*/
#define PCH_SPI_MAX_DEV 2
#define PCH_BUF_SIZE 4096
#define PCH_DMA_TRANS_SIZE 12
static int use_dma = 1;
struct pch_spi_dma_ctrl {
struct dma_async_tx_descriptor *desc_tx;
struct dma_async_tx_descriptor *desc_rx;
struct pch_dma_slave param_tx;
struct pch_dma_slave param_rx;
struct dma_chan *chan_tx;
struct dma_chan *chan_rx;
struct scatterlist *sg_tx_p;
struct scatterlist *sg_rx_p;
struct scatterlist sg_tx;
struct scatterlist sg_rx;
int nent;
void *tx_buf_virt;
void *rx_buf_virt;
dma_addr_t tx_buf_dma;
dma_addr_t rx_buf_dma;
};
/**
* struct pch_spi_data - Holds the SPI channel specific details
* @io_remap_addr: The remapped PCI base address
@ -140,6 +163,7 @@
*/
struct pch_spi_data {
void __iomem *io_remap_addr;
unsigned long io_base_addr;
struct spi_master *master;
struct work_struct work;
struct workqueue_struct *wk;
@ -162,6 +186,8 @@ struct pch_spi_data {
struct pch_spi_board_data *board_dat;
struct platform_device *plat_dev;
int ch;
struct pch_spi_dma_ctrl dma;
int use_dma;
u8 irq_reg_sts;
};
@ -273,10 +299,10 @@ static void pch_spi_handler_sub(struct pch_spi_data *data, u32 reg_spsr_val,
reg_spcr_val &= ~SPCR_RFIE_BIT; /* disable RFI */
/* reset rx threshold */
reg_spcr_val &= MASK_RFIC_SPCR_BITS;
reg_spcr_val &= ~MASK_RFIC_SPCR_BITS;
reg_spcr_val |= (PCH_RX_THOLD_MAX << SPCR_RFIC_FIELD);
iowrite32(((reg_spcr_val) &= (~(SPCR_RFIE_BIT))),
(io_remap_addr + PCH_SPCR));
iowrite32(reg_spcr_val, (io_remap_addr + PCH_SPCR));
}
/* update counts */
@ -287,12 +313,15 @@ static void pch_spi_handler_sub(struct pch_spi_data *data, u32 reg_spsr_val,
/* if transfer complete interrupt */
if (reg_spsr_val & SPSR_FI_BIT) {
/* disable FI & RFI interrupts */
pch_spi_setclr_reg(data->master, PCH_SPCR, 0,
SPCR_FIE_BIT | SPCR_RFIE_BIT);
if (tx_index < bpw_len)
dev_err(&data->master->dev,
"%s : Transfer is not completed", __func__);
/* disable interrupts */
pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL);
/* transfer is completed;inform pch_spi_process_messages */
data->transfer_complete = true;
data->transfer_active = false;
wake_up(&data->wait);
}
}
@ -316,12 +345,17 @@ static irqreturn_t pch_spi_handler(int irq, void *dev_id)
"%s returning due to suspend\n", __func__);
return IRQ_NONE;
}
if (data->use_dma)
return IRQ_NONE;
io_remap_addr = data->io_remap_addr;
spsr = io_remap_addr + PCH_SPSR;
reg_spsr_val = ioread32(spsr);
if (reg_spsr_val & SPSR_ORF_BIT)
dev_err(&board_dat->pdev->dev, "%s Over run error", __func__);
/* Check if the interrupt is for SPI device */
if (reg_spsr_val & (SPSR_FI_BIT | SPSR_RFI_BIT)) {
pch_spi_handler_sub(data, reg_spsr_val, io_remap_addr);
@ -347,7 +381,7 @@ static void pch_spi_set_baud_rate(struct spi_master *master, u32 speed_hz)
if (n_spbr > PCH_MAX_SPBR)
n_spbr = PCH_MAX_SPBR;
pch_spi_setclr_reg(master, PCH_SPBRR, n_spbr, ~MASK_SPBRR_SPBR_BITS);
pch_spi_setclr_reg(master, PCH_SPBRR, n_spbr, MASK_SPBRR_SPBR_BITS);
}
/**
@ -456,26 +490,27 @@ static int pch_spi_transfer(struct spi_device *pspi, struct spi_message *pmsg)
dev_dbg(&pspi->dev, "%s Transfer List not empty. "
"Transfer Speed is set.\n", __func__);
spin_lock_irqsave(&data->lock, flags);
/* validate Tx/Rx buffers and Transfer length */
list_for_each_entry(transfer, &pmsg->transfers, transfer_list) {
if (!transfer->tx_buf && !transfer->rx_buf) {
dev_err(&pspi->dev,
"%s Tx and Rx buffer NULL\n", __func__);
retval = -EINVAL;
goto err_out;
goto err_return_spinlock;
}
if (!transfer->len) {
dev_err(&pspi->dev, "%s Transfer length invalid\n",
__func__);
retval = -EINVAL;
goto err_out;
goto err_return_spinlock;
}
dev_dbg(&pspi->dev, "%s Tx/Rx buffer valid. Transfer length"
" valid\n", __func__);
/* if baud rate hs been specified validate the same */
/* if baud rate has been specified validate the same */
if (transfer->speed_hz > PCH_MAX_BAUDRATE)
transfer->speed_hz = PCH_MAX_BAUDRATE;
@ -486,25 +521,24 @@ static int pch_spi_transfer(struct spi_device *pspi, struct spi_message *pmsg)
retval = -EINVAL;
dev_err(&pspi->dev,
"%s Invalid bits per word\n", __func__);
goto err_out;
goto err_return_spinlock;
}
}
}
spin_lock_irqsave(&data->lock, flags);
spin_unlock_irqrestore(&data->lock, flags);
/* We won't process any messages if we have been asked to terminate */
if (data->status == STATUS_EXITING) {
dev_err(&pspi->dev, "%s status = STATUS_EXITING.\n", __func__);
retval = -ESHUTDOWN;
goto err_return_spinlock;
goto err_out;
}
/* If suspended ,return -EINVAL */
if (data->board_dat->suspend_sts) {
dev_err(&pspi->dev, "%s suspend; returning EINVAL\n", __func__);
retval = -EINVAL;
goto err_return_spinlock;
goto err_out;
}
/* set status of message */
@ -512,9 +546,11 @@ static int pch_spi_transfer(struct spi_device *pspi, struct spi_message *pmsg)
dev_dbg(&pspi->dev, "%s - pmsg->status =%d\n", __func__, pmsg->status);
pmsg->status = -EINPROGRESS;
spin_lock_irqsave(&data->lock, flags);
/* add message to queue */
list_add_tail(&pmsg->queue, &data->queue);
spin_unlock_irqrestore(&data->lock, flags);
dev_dbg(&pspi->dev, "%s - Invoked list_add_tail\n", __func__);
/* schedule work queue to run */
@ -523,11 +559,13 @@ static int pch_spi_transfer(struct spi_device *pspi, struct spi_message *pmsg)
retval = 0;
err_return_spinlock:
spin_unlock_irqrestore(&data->lock, flags);
err_out:
dev_dbg(&pspi->dev, "%s RETURN=%d\n", __func__, retval);
return retval;
err_return_spinlock:
dev_dbg(&pspi->dev, "%s RETURN=%d\n", __func__, retval);
spin_unlock_irqrestore(&data->lock, flags);
return retval;
}
static inline void pch_spi_select_chip(struct pch_spi_data *data,
@ -548,8 +586,7 @@ static inline void pch_spi_select_chip(struct pch_spi_data *data,
pch_spi_setup_transfer(pspi);
}
static void pch_spi_set_tx(struct pch_spi_data *data, int *bpw,
struct spi_message **ppmsg)
static void pch_spi_set_tx(struct pch_spi_data *data, int *bpw)
{
int size;
u32 n_writes;
@ -558,8 +595,6 @@ static void pch_spi_set_tx(struct pch_spi_data *data, int *bpw,
const u8 *tx_buf;
const u16 *tx_sbuf;
pmsg = *ppmsg;
/* set baud rate if needed */
if (data->cur_trans->speed_hz) {
dev_dbg(&data->master->dev, "%s:setting baud rate\n", __func__);
@ -642,10 +677,9 @@ static void pch_spi_set_tx(struct pch_spi_data *data, int *bpw,
data->transfer_active = true;
}
static void pch_spi_nomore_transfer(struct pch_spi_data *data,
struct spi_message *pmsg)
static void pch_spi_nomore_transfer(struct pch_spi_data *data)
{
struct spi_message *pmsg;
dev_dbg(&data->master->dev, "%s called\n", __func__);
/* Invoke complete callback
* [To the spi core..indicating end of transfer] */
@ -696,29 +730,21 @@ static void pch_spi_nomore_transfer(struct pch_spi_data *data,
static void pch_spi_set_ir(struct pch_spi_data *data)
{
/* enable interrupts */
if ((data->bpw_len) > PCH_MAX_FIFO_DEPTH) {
/* enable interrupts, set threshold, enable SPI */
if ((data->bpw_len) > PCH_MAX_FIFO_DEPTH)
/* set receive threshold to PCH_RX_THOLD */
pch_spi_setclr_reg(data->master, PCH_SPCR,
PCH_RX_THOLD << SPCR_RFIC_FIELD,
~MASK_RFIC_SPCR_BITS);
/* enable FI and RFI interrupts */
pch_spi_setclr_reg(data->master, PCH_SPCR,
SPCR_RFIE_BIT | SPCR_FIE_BIT, 0);
} else {
PCH_RX_THOLD << SPCR_RFIC_FIELD |
SPCR_FIE_BIT | SPCR_RFIE_BIT |
SPCR_ORIE_BIT | SPCR_SPE_BIT,
MASK_RFIC_SPCR_BITS | PCH_ALL);
else
/* set receive threshold to maximum */
pch_spi_setclr_reg(data->master, PCH_SPCR,
PCH_RX_THOLD_MAX << SPCR_TFIC_FIELD,
~MASK_TFIC_SPCR_BITS);
/* enable FI interrupt */
pch_spi_setclr_reg(data->master, PCH_SPCR, SPCR_FIE_BIT, 0);
}
dev_dbg(&data->master->dev,
"%s:invoking pch_spi_set_enable to enable SPI\n", __func__);
/* SPI set enable */
pch_spi_setclr_reg(data->current_chip->master, PCH_SPCR, SPCR_SPE_BIT, 0);
PCH_RX_THOLD_MAX << SPCR_RFIC_FIELD |
SPCR_FIE_BIT | SPCR_ORIE_BIT |
SPCR_SPE_BIT,
MASK_RFIC_SPCR_BITS | PCH_ALL);
/* Wait until the transfer completes; go to sleep after
initiating the transfer. */
@ -731,15 +757,13 @@ static void pch_spi_set_ir(struct pch_spi_data *data)
dev_dbg(&data->master->dev,
"%s:no more control over SSN-writing 0 to SSNXCR.", __func__);
data->transfer_active = false;
dev_dbg(&data->master->dev,
"%s set data->transfer_active = false\n", __func__);
/* clear all interrupts */
pch_spi_writereg(data->master, PCH_SPSR,
pch_spi_readreg(data->master, PCH_SPSR));
/* disable interrupts */
pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL);
/* Disable interrupts and SPI transfer */
pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL | SPCR_SPE_BIT);
/* clear FIFO */
pch_spi_clear_fifo(data->master);
}
static void pch_spi_copy_rx_data(struct pch_spi_data *data, int bpw)
@ -763,6 +787,327 @@ static void pch_spi_copy_rx_data(struct pch_spi_data *data, int bpw)
}
}
static void pch_spi_copy_rx_data_for_dma(struct pch_spi_data *data, int bpw)
{
int j;
u8 *rx_buf;
u16 *rx_sbuf;
const u8 *rx_dma_buf;
const u16 *rx_dma_sbuf;
/* copy Rx Data */
if (!data->cur_trans->rx_buf)
return;
if (bpw == 8) {
rx_buf = data->cur_trans->rx_buf;
rx_dma_buf = data->dma.rx_buf_virt;
for (j = 0; j < data->bpw_len; j++)
*rx_buf++ = *rx_dma_buf++ & 0xFF;
} else {
rx_sbuf = data->cur_trans->rx_buf;
rx_dma_sbuf = data->dma.rx_buf_virt;
for (j = 0; j < data->bpw_len; j++)
*rx_sbuf++ = *rx_dma_sbuf++;
}
}
static void pch_spi_start_transfer(struct pch_spi_data *data)
{
struct pch_spi_dma_ctrl *dma;
unsigned long flags;
dma = &data->dma;
spin_lock_irqsave(&data->lock, flags);
/* disable interrupts, SPI set enable */
pch_spi_setclr_reg(data->master, PCH_SPCR, SPCR_SPE_BIT, PCH_ALL);
spin_unlock_irqrestore(&data->lock, flags);
/* Wait until the transfer completes; go to sleep after
initiating the transfer. */
dev_dbg(&data->master->dev,
"%s:waiting for transfer to get over\n", __func__);
wait_event_interruptible(data->wait, data->transfer_complete);
dma_sync_sg_for_cpu(&data->master->dev, dma->sg_rx_p, dma->nent,
DMA_FROM_DEVICE);
async_tx_ack(dma->desc_rx);
async_tx_ack(dma->desc_tx);
kfree(dma->sg_tx_p);
kfree(dma->sg_rx_p);
spin_lock_irqsave(&data->lock, flags);
pch_spi_writereg(data->master, PCH_SSNXCR, SSN_NO_CONTROL);
dev_dbg(&data->master->dev,
"%s:no more control over SSN-writing 0 to SSNXCR.", __func__);
/* clear fifo threshold, disable interrupts, disable SPI transfer */
pch_spi_setclr_reg(data->master, PCH_SPCR, 0,
MASK_RFIC_SPCR_BITS | MASK_TFIC_SPCR_BITS | PCH_ALL |
SPCR_SPE_BIT);
/* clear all interrupts */
pch_spi_writereg(data->master, PCH_SPSR,
pch_spi_readreg(data->master, PCH_SPSR));
/* clear FIFO */
pch_spi_clear_fifo(data->master);
spin_unlock_irqrestore(&data->lock, flags);
}
static void pch_dma_rx_complete(void *arg)
{
struct pch_spi_data *data = arg;
/* transfer is completed;inform pch_spi_process_messages_dma */
data->transfer_complete = true;
wake_up_interruptible(&data->wait);
}
static bool pch_spi_filter(struct dma_chan *chan, void *slave)
{
struct pch_dma_slave *param = slave;
if ((chan->chan_id == param->chan_id) &&
(param->dma_dev == chan->device->dev)) {
chan->private = param;
return true;
} else {
return false;
}
}
static void pch_spi_request_dma(struct pch_spi_data *data, int bpw)
{
dma_cap_mask_t mask;
struct dma_chan *chan;
struct pci_dev *dma_dev;
struct pch_dma_slave *param;
struct pch_spi_dma_ctrl *dma;
unsigned int width;
if (bpw == 8)
width = PCH_DMA_WIDTH_1_BYTE;
else
width = PCH_DMA_WIDTH_2_BYTES;
dma = &data->dma;
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
/* Get DMA's dev information */
dma_dev = pci_get_bus_and_slot(2, PCI_DEVFN(12, 0));
/* Set Tx DMA */
param = &dma->param_tx;
param->dma_dev = &dma_dev->dev;
param->chan_id = data->master->bus_num * 2; /* Tx = 0, 2 */
param->tx_reg = data->io_base_addr + PCH_SPDWR;
param->width = width;
chan = dma_request_channel(mask, pch_spi_filter, param);
if (!chan) {
dev_err(&data->master->dev,
"ERROR: dma_request_channel FAILS(Tx)\n");
data->use_dma = 0;
return;
}
dma->chan_tx = chan;
/* Set Rx DMA */
param = &dma->param_rx;
param->dma_dev = &dma_dev->dev;
param->chan_id = data->master->bus_num * 2 + 1; /* Rx = Tx + 1 */
param->rx_reg = data->io_base_addr + PCH_SPDRR;
param->width = width;
chan = dma_request_channel(mask, pch_spi_filter, param);
if (!chan) {
dev_err(&data->master->dev,
"ERROR: dma_request_channel FAILS(Rx)\n");
dma_release_channel(dma->chan_tx);
dma->chan_tx = NULL;
data->use_dma = 0;
return;
}
dma->chan_rx = chan;
}
static void pch_spi_release_dma(struct pch_spi_data *data)
{
struct pch_spi_dma_ctrl *dma;
dma = &data->dma;
if (dma->chan_tx) {
dma_release_channel(dma->chan_tx);
dma->chan_tx = NULL;
}
if (dma->chan_rx) {
dma_release_channel(dma->chan_rx);
dma->chan_rx = NULL;
}
return;
}
static void pch_spi_handle_dma(struct pch_spi_data *data, int *bpw)
{
const u8 *tx_buf;
const u16 *tx_sbuf;
u8 *tx_dma_buf;
u16 *tx_dma_sbuf;
struct scatterlist *sg;
struct dma_async_tx_descriptor *desc_tx;
struct dma_async_tx_descriptor *desc_rx;
int num;
int i;
int size;
int rem;
unsigned long flags;
struct pch_spi_dma_ctrl *dma;
dma = &data->dma;
/* set baud rate if needed */
if (data->cur_trans->speed_hz) {
dev_dbg(&data->master->dev, "%s:setting baud rate\n", __func__);
spin_lock_irqsave(&data->lock, flags);
pch_spi_set_baud_rate(data->master, data->cur_trans->speed_hz);
spin_unlock_irqrestore(&data->lock, flags);
}
/* set bits per word if needed */
if (data->cur_trans->bits_per_word &&
(data->current_msg->spi->bits_per_word !=
data->cur_trans->bits_per_word)) {
dev_dbg(&data->master->dev, "%s:set bits per word\n", __func__);
spin_lock_irqsave(&data->lock, flags);
pch_spi_set_bits_per_word(data->master,
data->cur_trans->bits_per_word);
spin_unlock_irqrestore(&data->lock, flags);
*bpw = data->cur_trans->bits_per_word;
} else {
*bpw = data->current_msg->spi->bits_per_word;
}
data->bpw_len = data->cur_trans->len / (*bpw / 8);
/* copy Tx Data */
if (data->cur_trans->tx_buf != NULL) {
if (*bpw == 8) {
tx_buf = data->cur_trans->tx_buf;
tx_dma_buf = dma->tx_buf_virt;
for (i = 0; i < data->bpw_len; i++)
*tx_dma_buf++ = *tx_buf++;
} else {
tx_sbuf = data->cur_trans->tx_buf;
tx_dma_sbuf = dma->tx_buf_virt;
for (i = 0; i < data->bpw_len; i++)
*tx_dma_sbuf++ = *tx_sbuf++;
}
}
if (data->bpw_len > PCH_DMA_TRANS_SIZE) {
num = data->bpw_len / PCH_DMA_TRANS_SIZE + 1;
size = PCH_DMA_TRANS_SIZE;
rem = data->bpw_len % PCH_DMA_TRANS_SIZE;
} else {
num = 1;
size = data->bpw_len;
rem = data->bpw_len;
}
dev_dbg(&data->master->dev, "%s num=%d size=%d rem=%d\n",
__func__, num, size, rem);
spin_lock_irqsave(&data->lock, flags);
/* set receive fifo threshold and transmit fifo threshold */
pch_spi_setclr_reg(data->master, PCH_SPCR,
((size - 1) << SPCR_RFIC_FIELD) |
((PCH_MAX_FIFO_DEPTH - PCH_DMA_TRANS_SIZE) <<
SPCR_TFIC_FIELD),
MASK_RFIC_SPCR_BITS | MASK_TFIC_SPCR_BITS);
spin_unlock_irqrestore(&data->lock, flags);
/* RX */
dma->sg_rx_p = kzalloc(sizeof(struct scatterlist)*num, GFP_ATOMIC);
sg_init_table(dma->sg_rx_p, num); /* Initialize SG table */
/* offset, length setting */
sg = dma->sg_rx_p;
for (i = 0; i < num; i++, sg++) {
if (i == 0) {
sg->offset = 0;
sg_set_page(sg, virt_to_page(dma->rx_buf_virt), rem,
sg->offset);
sg_dma_len(sg) = rem;
} else {
sg->offset = rem + size * (i - 1);
sg->offset = sg->offset * (*bpw / 8);
sg_set_page(sg, virt_to_page(dma->rx_buf_virt), size,
sg->offset);
sg_dma_len(sg) = size;
}
sg_dma_address(sg) = dma->rx_buf_dma + sg->offset;
}
sg = dma->sg_rx_p;
desc_rx = dma->chan_rx->device->device_prep_slave_sg(dma->chan_rx, sg,
num, DMA_FROM_DEVICE,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc_rx) {
dev_err(&data->master->dev, "%s:device_prep_slave_sg Failed\n",
__func__);
return;
}
dma_sync_sg_for_device(&data->master->dev, sg, num, DMA_FROM_DEVICE);
desc_rx->callback = pch_dma_rx_complete;
desc_rx->callback_param = data;
dma->nent = num;
dma->desc_rx = desc_rx;
/* TX */
dma->sg_tx_p = kzalloc(sizeof(struct scatterlist)*num, GFP_ATOMIC);
sg_init_table(dma->sg_tx_p, num); /* Initialize SG table */
/* offset, length setting */
sg = dma->sg_tx_p;
for (i = 0; i < num; i++, sg++) {
if (i == 0) {
sg->offset = 0;
sg_set_page(sg, virt_to_page(dma->tx_buf_virt), rem,
sg->offset);
sg_dma_len(sg) = rem;
} else {
sg->offset = rem + size * (i - 1);
sg->offset = sg->offset * (*bpw / 8);
sg_set_page(sg, virt_to_page(dma->tx_buf_virt), size,
sg->offset);
sg_dma_len(sg) = size;
}
sg_dma_address(sg) = dma->tx_buf_dma + sg->offset;
}
sg = dma->sg_tx_p;
desc_tx = dma->chan_tx->device->device_prep_slave_sg(dma->chan_tx,
sg, num, DMA_TO_DEVICE,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc_tx) {
dev_err(&data->master->dev, "%s:device_prep_slave_sg Failed\n",
__func__);
return;
}
dma_sync_sg_for_device(&data->master->dev, sg, num, DMA_TO_DEVICE);
desc_tx->callback = NULL;
desc_tx->callback_param = data;
dma->nent = num;
dma->desc_tx = desc_tx;
dev_dbg(&data->master->dev, "\n%s:Pulling down SSN low - writing "
"0x2 to SSNXCR\n", __func__);
spin_lock_irqsave(&data->lock, flags);
pch_spi_writereg(data->master, PCH_SSNXCR, SSN_LOW);
desc_rx->tx_submit(desc_rx);
desc_tx->tx_submit(desc_tx);
spin_unlock_irqrestore(&data->lock, flags);
/* reset transfer complete flag */
data->transfer_complete = false;
}
static void pch_spi_process_messages(struct work_struct *pwork)
{
@ -774,13 +1119,10 @@ static void pch_spi_process_messages(struct work_struct *pwork)
dev_dbg(&data->master->dev, "%s data initialized\n", __func__);
spin_lock(&data->lock);
/* check if suspend has been initiated;if yes flush queue */
if (data->board_dat->suspend_sts || (data->status == STATUS_EXITING)) {
dev_dbg(&data->master->dev,
"%s suspend/remove initiated,flushing queue\n",
__func__);
dev_dbg(&data->master->dev, "%s suspend/remove initiated,"
"flushing queue\n", __func__);
list_for_each_entry(pmsg, data->queue.next, queue) {
pmsg->status = -EIO;
@ -814,53 +1156,42 @@ static void pch_spi_process_messages(struct work_struct *pwork)
spin_unlock(&data->lock);
if (data->use_dma)
pch_spi_request_dma(data,
data->current_msg->spi->bits_per_word);
do {
/* If we are already processing a message get the next
transfer structure from the message otherwise retrieve
the 1st transfer request from the message. */
spin_lock(&data->lock);
if (data->cur_trans == NULL) {
data->cur_trans =
list_entry(data->current_msg->transfers.
next, struct spi_transfer,
transfer_list);
dev_dbg(&data->master->dev,
"%s :Getting 1st transfer message\n", __func__);
list_entry(data->current_msg->transfers.next,
struct spi_transfer, transfer_list);
dev_dbg(&data->master->dev, "%s "
":Getting 1st transfer message\n", __func__);
} else {
data->cur_trans =
list_entry(data->cur_trans->transfer_list.next,
struct spi_transfer,
transfer_list);
dev_dbg(&data->master->dev,
"%s :Getting next transfer message\n",
__func__);
list_entry(data->cur_trans->transfer_list.next,
struct spi_transfer, transfer_list);
dev_dbg(&data->master->dev, "%s "
":Getting next transfer message\n", __func__);
}
spin_unlock(&data->lock);
pch_spi_set_tx(data, &bpw, &pmsg);
/* Control interrupt*/
pch_spi_set_ir(data);
/* Disable SPI transfer */
pch_spi_setclr_reg(data->current_chip->master, PCH_SPCR, 0,
SPCR_SPE_BIT);
/* clear FIFO */
pch_spi_clear_fifo(data->master);
/* copy Rx Data */
pch_spi_copy_rx_data(data, bpw);
/* free memory */
kfree(data->pkt_rx_buff);
data->pkt_rx_buff = NULL;
kfree(data->pkt_tx_buff);
data->pkt_tx_buff = NULL;
if (data->use_dma) {
pch_spi_handle_dma(data, &bpw);
pch_spi_start_transfer(data);
pch_spi_copy_rx_data_for_dma(data, bpw);
} else {
pch_spi_set_tx(data, &bpw);
pch_spi_set_ir(data);
pch_spi_copy_rx_data(data, bpw);
kfree(data->pkt_rx_buff);
data->pkt_rx_buff = NULL;
kfree(data->pkt_tx_buff);
data->pkt_tx_buff = NULL;
}
/* increment message count */
data->current_msg->actual_length += data->cur_trans->len;
@ -881,12 +1212,15 @@ static void pch_spi_process_messages(struct work_struct *pwork)
/* No more transfer in this message. */
if ((data->cur_trans->transfer_list.next) ==
&(data->current_msg->transfers)) {
pch_spi_nomore_transfer(data, pmsg);
pch_spi_nomore_transfer(data);
}
spin_unlock(&data->lock);
} while (data->cur_trans != NULL);
if (data->use_dma)
pch_spi_release_dma(data);
}
static void pch_spi_free_resources(struct pch_spi_board_data *board_dat,
@ -939,6 +1273,35 @@ err_return:
return retval;
}
static void pch_free_dma_buf(struct pch_spi_board_data *board_dat,
struct pch_spi_data *data)
{
struct pch_spi_dma_ctrl *dma;
dma = &data->dma;
if (dma->tx_buf_dma)
dma_free_coherent(&board_dat->pdev->dev, PCH_BUF_SIZE,
dma->tx_buf_virt, dma->tx_buf_dma);
if (dma->rx_buf_dma)
dma_free_coherent(&board_dat->pdev->dev, PCH_BUF_SIZE,
dma->rx_buf_virt, dma->rx_buf_dma);
return;
}
static void pch_alloc_dma_buf(struct pch_spi_board_data *board_dat,
struct pch_spi_data *data)
{
struct pch_spi_dma_ctrl *dma;
dma = &data->dma;
/* Get Consistent memory for Tx DMA */
dma->tx_buf_virt = dma_alloc_coherent(&board_dat->pdev->dev,
PCH_BUF_SIZE, &dma->tx_buf_dma, GFP_KERNEL);
/* Get Consistent memory for Rx DMA */
dma->rx_buf_virt = dma_alloc_coherent(&board_dat->pdev->dev,
PCH_BUF_SIZE, &dma->rx_buf_dma, GFP_KERNEL);
}
static int __devinit pch_spi_pd_probe(struct platform_device *plat_dev)
{
int ret;
@ -946,6 +1309,8 @@ static int __devinit pch_spi_pd_probe(struct platform_device *plat_dev)
struct pch_spi_board_data *board_dat = dev_get_platdata(&plat_dev->dev);
struct pch_spi_data *data;
dev_dbg(&plat_dev->dev, "%s:debug\n", __func__);
master = spi_alloc_master(&board_dat->pdev->dev,
sizeof(struct pch_spi_data));
if (!master) {
@ -959,9 +1324,11 @@ static int __devinit pch_spi_pd_probe(struct platform_device *plat_dev)
platform_set_drvdata(plat_dev, data);
/* baseaddress + 0x20(offset) */
/* baseaddress + address offset) */
data->io_base_addr = pci_resource_start(board_dat->pdev, 1) +
PCH_ADDRESS_SIZE * plat_dev->id;
data->io_remap_addr = pci_iomap(board_dat->pdev, 1, 0) +
0x20 * plat_dev->id;
PCH_ADDRESS_SIZE * plat_dev->id;
if (!data->io_remap_addr) {
dev_err(&plat_dev->dev, "%s pci_iomap failed\n", __func__);
ret = -ENOMEM;
@ -982,6 +1349,7 @@ static int __devinit pch_spi_pd_probe(struct platform_device *plat_dev)
data->n_curnt_chip = 255;
data->status = STATUS_RUNNING;
data->ch = plat_dev->id;
data->use_dma = use_dma;
INIT_LIST_HEAD(&data->queue);
spin_lock_init(&data->lock);
@ -1012,6 +1380,11 @@ static int __devinit pch_spi_pd_probe(struct platform_device *plat_dev)
goto err_spi_register_master;
}
if (use_dma) {
dev_info(&plat_dev->dev, "Use DMA for data transfers\n");
pch_alloc_dma_buf(board_dat, data);
}
return 0;
err_spi_register_master:
@ -1031,22 +1404,27 @@ static int __devexit pch_spi_pd_remove(struct platform_device *plat_dev)
struct pch_spi_board_data *board_dat = dev_get_platdata(&plat_dev->dev);
struct pch_spi_data *data = platform_get_drvdata(plat_dev);
int count;
unsigned long flags;
dev_dbg(&plat_dev->dev, "%s:[ch%d] irq=%d\n",
__func__, plat_dev->id, board_dat->pdev->irq);
if (use_dma)
pch_free_dma_buf(board_dat, data);
/* check for any pending messages; no action is taken if the queue
* is still full; but at least we tried. Unload anyway */
count = 500;
spin_lock(&data->lock);
spin_lock_irqsave(&data->lock, flags);
data->status = STATUS_EXITING;
while ((list_empty(&data->queue) == 0) && --count) {
dev_dbg(&board_dat->pdev->dev, "%s :queue not empty\n",
__func__);
spin_unlock(&data->lock);
spin_unlock_irqrestore(&data->lock, flags);
msleep(PCH_SLEEP_TIME);
spin_lock(&data->lock);
spin_lock_irqsave(&data->lock, flags);
}
spin_unlock(&data->lock);
spin_unlock_irqrestore(&data->lock, flags);
pch_spi_free_resources(board_dat, data);
/* disable interrupts & free IRQ */
@ -1083,8 +1461,8 @@ static int pch_spi_pd_suspend(struct platform_device *pd_dev,
/* check if the current message is processed:
Only after thats done the transfer will be suspended */
count = 255;
while ((--count) > 0)
if (!(data->bcurrent_msg_processing)) {
while ((--count) > 0) {
if (!(data->bcurrent_msg_processing))
break;
msleep(PCH_SLEEP_TIME);
}
@ -1328,5 +1706,9 @@ static void __exit pch_spi_exit(void)
}
module_exit(pch_spi_exit);
module_param(use_dma, int, 0644);
MODULE_PARM_DESC(use_dma,
"to use DMA for data transfers pass 1 else 0; default 1");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Intel EG20T PCH/OKI SEMICONDUCTOR ML7213 IOH SPI Driver");