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spi: atmel: Refactor spi-atmel to use SPI framework queue

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Replace the deprecated master->transfer with transfer_one_message()
and allow the SPI subsystem handle all the queuing of messages.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Tested-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
This commit is contained in:
Wenyou Yang 2014-01-09 13:19:15 +08:00 committed by Mark Brown
parent d3b72c7e6b
commit 8090d6d1a4
1 changed files with 229 additions and 467 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

696
drivers/spi/spi-atmel.c
View file

@ -189,6 +189,8 @@
*/ */
#define DMA_MIN_BYTES 16 #define DMA_MIN_BYTES 16
#define SPI_DMA_TIMEOUT (msecs_to_jiffies(1000))
struct atmel_spi_dma { struct atmel_spi_dma {
struct dma_chan *chan_rx; struct dma_chan *chan_rx;
struct dma_chan *chan_tx; struct dma_chan *chan_tx;
@ -220,17 +222,13 @@ struct atmel_spi {
int irq; int irq;
struct clk *clk; struct clk *clk;
struct platform_device *pdev; struct platform_device *pdev;
struct spi_device *stay;
u8 stopping;
struct list_head queue;
struct tasklet_struct tasklet;
struct spi_transfer *current_transfer; struct spi_transfer *current_transfer;
unsigned long current_remaining_bytes; unsigned long current_remaining_bytes;
struct spi_transfer *next_transfer;
unsigned long next_remaining_bytes;
int done_status; int done_status;
struct completion xfer_completion;
/* scratch buffer */ /* scratch buffer */
void *buffer; void *buffer;
dma_addr_t buffer_dma; dma_addr_t buffer_dma;
@ -241,6 +239,9 @@ struct atmel_spi {
bool use_pdc; bool use_pdc;
/* dmaengine data */ /* dmaengine data */
struct atmel_spi_dma dma; struct atmel_spi_dma dma;
bool keep_cs;
bool cs_active;
}; };
/* Controller-specific per-slave state */ /* Controller-specific per-slave state */
@ -376,17 +377,6 @@ static inline bool atmel_spi_use_dma(struct atmel_spi *as,
return as->use_dma && xfer->len >= DMA_MIN_BYTES; return as->use_dma && xfer->len >= DMA_MIN_BYTES;
} }
static inline int atmel_spi_xfer_is_last(struct spi_message *msg,
struct spi_transfer *xfer)
{
return msg->transfers.prev == &xfer->transfer_list;
}
static inline int atmel_spi_xfer_can_be_chained(struct spi_transfer *xfer)
{
return xfer->delay_usecs == 0 && !xfer->cs_change;
}
static int atmel_spi_dma_slave_config(struct atmel_spi *as, static int atmel_spi_dma_slave_config(struct atmel_spi *as,
struct dma_slave_config *slave_config, struct dma_slave_config *slave_config,
u8 bits_per_word) u8 bits_per_word)
@ -513,23 +503,20 @@ static void dma_callback(void *data)
struct spi_master *master = data; struct spi_master *master = data;
struct atmel_spi *as = spi_master_get_devdata(master); struct atmel_spi *as = spi_master_get_devdata(master);
/* trigger SPI tasklet */ complete(&as->xfer_completion);
tasklet_schedule(&as->tasklet);
} }
/* /*
* Next transfer using PIO. * Next transfer using PIO.
* lock is held, spi tasklet is blocked
*/ */
static void atmel_spi_next_xfer_pio(struct spi_master *master, static void atmel_spi_next_xfer_pio(struct spi_master *master,
struct spi_transfer *xfer) struct spi_transfer *xfer)
{ {
struct atmel_spi *as = spi_master_get_devdata(master); struct atmel_spi *as = spi_master_get_devdata(master);
unsigned long xfer_pos = xfer->len - as->current_remaining_bytes;
dev_vdbg(master->dev.parent, "atmel_spi_next_xfer_pio\n"); dev_vdbg(master->dev.parent, "atmel_spi_next_xfer_pio\n");
as->current_remaining_bytes = xfer->len;
/* Make sure data is not remaining in RDR */ /* Make sure data is not remaining in RDR */
spi_readl(as, RDR); spi_readl(as, RDR);
while (spi_readl(as, SR) & SPI_BIT(RDRF)) { while (spi_readl(as, SR) & SPI_BIT(RDRF)) {
@ -537,13 +524,14 @@ static void atmel_spi_next_xfer_pio(struct spi_master *master,
cpu_relax(); cpu_relax();
} }
if (xfer->tx_buf) if (xfer->tx_buf) {
if (xfer->bits_per_word > 8) if (xfer->bits_per_word > 8)
spi_writel(as, TDR, *(u16 *)(xfer->tx_buf)); spi_writel(as, TDR, *(u16 *)(xfer->tx_buf + xfer_pos));
else else
spi_writel(as, TDR, *(u8 *)(xfer->tx_buf)); spi_writel(as, TDR, *(u8 *)(xfer->tx_buf + xfer_pos));
else } else {
spi_writel(as, TDR, 0); spi_writel(as, TDR, 0);
}
dev_dbg(master->dev.parent, dev_dbg(master->dev.parent,
" start pio xfer %p: len %u tx %p rx %p bitpw %d\n", " start pio xfer %p: len %u tx %p rx %p bitpw %d\n",
@ -556,7 +544,6 @@ static void atmel_spi_next_xfer_pio(struct spi_master *master,
/* /*
* Submit next transfer for DMA. * Submit next transfer for DMA.
* lock is held, spi tasklet is blocked
*/ */
static int atmel_spi_next_xfer_dma_submit(struct spi_master *master, static int atmel_spi_next_xfer_dma_submit(struct spi_master *master,
struct spi_transfer *xfer, struct spi_transfer *xfer,
@ -747,71 +734,37 @@ static int atmel_spi_set_xfer_speed(struct atmel_spi *as,
* lock is held, spi irq is blocked * lock is held, spi irq is blocked
*/ */
static void atmel_spi_pdc_next_xfer(struct spi_master *master, static void atmel_spi_pdc_next_xfer(struct spi_master *master,
struct spi_message *msg) struct spi_message *msg,
struct spi_transfer *xfer)
{ {
struct atmel_spi *as = spi_master_get_devdata(master); struct atmel_spi *as = spi_master_get_devdata(master);
struct spi_transfer *xfer; u32 len;
u32 len, remaining;
u32 ieval;
dma_addr_t tx_dma, rx_dma; dma_addr_t tx_dma, rx_dma;
if (!as->current_transfer) spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS));
xfer = list_entry(msg->transfers.next,
struct spi_transfer, transfer_list);
else if (!as->next_transfer)
xfer = list_entry(as->current_transfer->transfer_list.next,
struct spi_transfer, transfer_list);
else
xfer = NULL;
if (xfer) { len = as->current_remaining_bytes;
spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS)); atmel_spi_next_xfer_data(master, xfer, &tx_dma, &rx_dma, &len);
as->current_remaining_bytes -= len;
len = xfer->len; spi_writel(as, RPR, rx_dma);
spi_writel(as, TPR, tx_dma);
if (msg->spi->bits_per_word > 8)
len >>= 1;
spi_writel(as, RCR, len);
spi_writel(as, TCR, len);
dev_dbg(&msg->spi->dev,
" start xfer %p: len %u tx %p/%08llx rx %p/%08llx\n",
xfer, xfer->len, xfer->tx_buf,
(unsigned long long)xfer->tx_dma, xfer->rx_buf,
(unsigned long long)xfer->rx_dma);
if (as->current_remaining_bytes) {
len = as->current_remaining_bytes;
atmel_spi_next_xfer_data(master, xfer, &tx_dma, &rx_dma, &len); atmel_spi_next_xfer_data(master, xfer, &tx_dma, &rx_dma, &len);
remaining = xfer->len - len; as->current_remaining_bytes -= len;
spi_writel(as, RPR, rx_dma);
spi_writel(as, TPR, tx_dma);
if (msg->spi->bits_per_word > 8)
len >>= 1;
spi_writel(as, RCR, len);
spi_writel(as, TCR, len);
atmel_spi_set_xfer_speed(as, msg->spi, xfer);
dev_dbg(&msg->spi->dev,
" start xfer %p: len %u tx %p/%08llx rx %p/%08llx\n",
xfer, xfer->len, xfer->tx_buf,
(unsigned long long)xfer->tx_dma, xfer->rx_buf,
(unsigned long long)xfer->rx_dma);
} else {
xfer = as->next_transfer;
remaining = as->next_remaining_bytes;
}
as->current_transfer = xfer;
as->current_remaining_bytes = remaining;
if (remaining > 0)
len = remaining;
else if (!atmel_spi_xfer_is_last(msg, xfer)
&& atmel_spi_xfer_can_be_chained(xfer)) {
xfer = list_entry(xfer->transfer_list.next,
struct spi_transfer, transfer_list);
len = xfer->len;
} else
xfer = NULL;
as->next_transfer = xfer;
if (xfer) {
u32 total;
total = len;
atmel_spi_next_xfer_data(master, xfer, &tx_dma, &rx_dma, &len);
as->next_remaining_bytes = total - len;
spi_writel(as, RNPR, rx_dma); spi_writel(as, RNPR, rx_dma);
spi_writel(as, TNPR, tx_dma); spi_writel(as, TNPR, tx_dma);
@ -826,11 +779,6 @@ static void atmel_spi_pdc_next_xfer(struct spi_master *master,
xfer, xfer->len, xfer->tx_buf, xfer, xfer->len, xfer->tx_buf,
(unsigned long long)xfer->tx_dma, xfer->rx_buf, (unsigned long long)xfer->tx_dma, xfer->rx_buf,
(unsigned long long)xfer->rx_dma); (unsigned long long)xfer->rx_dma);
ieval = SPI_BIT(ENDRX) | SPI_BIT(OVRES);
} else {
spi_writel(as, RNCR, 0);
spi_writel(as, TNCR, 0);
ieval = SPI_BIT(RXBUFF) | SPI_BIT(ENDRX) | SPI_BIT(OVRES);
} }
/* REVISIT: We're waiting for ENDRX before we start the next /* REVISIT: We're waiting for ENDRX before we start the next
@ -843,83 +791,10 @@ static void atmel_spi_pdc_next_xfer(struct spi_master *master,
* *
* It should be doable, though. Just not now... * It should be doable, though. Just not now...
*/ */
spi_writel(as, IER, ieval); spi_writel(as, IER, SPI_BIT(ENDRX) | SPI_BIT(OVRES));
spi_writel(as, PTCR, SPI_BIT(TXTEN) | SPI_BIT(RXTEN)); spi_writel(as, PTCR, SPI_BIT(TXTEN) | SPI_BIT(RXTEN));
} }
/*
* Choose way to submit next transfer and start it.
* lock is held, spi tasklet is blocked
*/
static void atmel_spi_dma_next_xfer(struct spi_master *master,
struct spi_message *msg)
{
struct atmel_spi *as = spi_master_get_devdata(master);
struct spi_transfer *xfer;
u32 remaining, len;
remaining = as->current_remaining_bytes;
if (remaining) {
xfer = as->current_transfer;
len = remaining;
} else {
if (!as->current_transfer)
xfer = list_entry(msg->transfers.next,
struct spi_transfer, transfer_list);
else
xfer = list_entry(
as->current_transfer->transfer_list.next,
struct spi_transfer, transfer_list);
as->current_transfer = xfer;
len = xfer->len;
atmel_spi_set_xfer_speed(as, msg->spi, xfer);
}
if (atmel_spi_use_dma(as, xfer)) {
u32 total = len;
if (!atmel_spi_next_xfer_dma_submit(master, xfer, &len)) {
as->current_remaining_bytes = total - len;
return;
} else {
dev_err(&msg->spi->dev, "unable to use DMA, fallback to PIO\n");
}
}
/* use PIO if error appened using DMA */
atmel_spi_next_xfer_pio(master, xfer);
}
static void atmel_spi_next_message(struct spi_master *master)
{
struct atmel_spi *as = spi_master_get_devdata(master);
struct spi_message *msg;
struct spi_device *spi;
BUG_ON(as->current_transfer);
msg = list_entry(as->queue.next, struct spi_message, queue);
spi = msg->spi;
dev_dbg(master->dev.parent, "start message %p for %s\n",
msg, dev_name(&spi->dev));
/* select chip if it's not still active */
if (as->stay) {
if (as->stay != spi) {
cs_deactivate(as, as->stay);
cs_activate(as, spi);
}
as->stay = NULL;
} else
cs_activate(as, spi);
if (as->use_pdc)
atmel_spi_pdc_next_xfer(master, msg);
else
atmel_spi_dma_next_xfer(master, msg);
}
/* /*
* For DMA, tx_buf/tx_dma have the same relationship as rx_buf/rx_dma: * For DMA, tx_buf/tx_dma have the same relationship as rx_buf/rx_dma:
* - The buffer is either valid for CPU access, else NULL * - The buffer is either valid for CPU access, else NULL
@ -975,41 +850,7 @@ static void atmel_spi_disable_pdc_transfer(struct atmel_spi *as)
spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS)); spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS));
} }
static void
atmel_spi_msg_done(struct spi_master *master, struct atmel_spi *as,
struct spi_message *msg, int stay)
{
if (!stay || as->done_status < 0)
cs_deactivate(as, msg->spi);
else
as->stay = msg->spi;
list_del(&msg->queue);
msg->status = as->done_status;
dev_dbg(master->dev.parent,
"xfer complete: %u bytes transferred\n",
msg->actual_length);
atmel_spi_unlock(as);
msg->complete(msg->context);
atmel_spi_lock(as);
as->current_transfer = NULL;
as->next_transfer = NULL;
as->done_status = 0;
/* continue if needed */
if (list_empty(&as->queue) || as->stopping) {
if (as->use_pdc)
atmel_spi_disable_pdc_transfer(as);
} else {
atmel_spi_next_message(master);
}
}
/* Called from IRQ /* Called from IRQ
* lock is held
* *
* Must update "current_remaining_bytes" to keep track of data * Must update "current_remaining_bytes" to keep track of data
* to transfer. * to transfer.
@ -1017,9 +858,7 @@ atmel_spi_msg_done(struct spi_master *master, struct atmel_spi *as,
static void static void
atmel_spi_pump_pio_data(struct atmel_spi *as, struct spi_transfer *xfer) atmel_spi_pump_pio_data(struct atmel_spi *as, struct spi_transfer *xfer)
{ {
u8 *txp;
u8 *rxp; u8 *rxp;
u16 *txp16;
u16 *rxp16; u16 *rxp16;
unsigned long xfer_pos = xfer->len - as->current_remaining_bytes; unsigned long xfer_pos = xfer->len - as->current_remaining_bytes;
@ -1041,96 +880,12 @@ atmel_spi_pump_pio_data(struct atmel_spi *as, struct spi_transfer *xfer)
} else { } else {
as->current_remaining_bytes--; as->current_remaining_bytes--;
} }
if (as->current_remaining_bytes) {
if (xfer->tx_buf) {
if (xfer->bits_per_word > 8) {
txp16 = (u16 *)(((u8 *)xfer->tx_buf)
+ xfer_pos + 2);
spi_writel(as, TDR, *txp16);
} else {
txp = ((u8 *)xfer->tx_buf) + xfer_pos + 1;
spi_writel(as, TDR, *txp);
}
} else {
spi_writel(as, TDR, 0);
}
}
}
/* Tasklet
* Called from DMA callback + pio transfer and overrun IRQ.
*/
static void atmel_spi_tasklet_func(unsigned long data)
{
struct spi_master *master = (struct spi_master *)data;
struct atmel_spi *as = spi_master_get_devdata(master);
struct spi_message *msg;
struct spi_transfer *xfer;
dev_vdbg(master->dev.parent, "atmel_spi_tasklet_func\n");
atmel_spi_lock(as);
xfer = as->current_transfer;
if (xfer == NULL)
/* already been there */
goto tasklet_out;
msg = list_entry(as->queue.next, struct spi_message, queue);
if (as->current_remaining_bytes == 0) {
if (as->done_status < 0) {
/* error happened (overrun) */
if (atmel_spi_use_dma(as, xfer))
atmel_spi_stop_dma(as);
} else {
/* only update length if no error */
msg->actual_length += xfer->len;
}
if (atmel_spi_use_dma(as, xfer))
if (!msg->is_dma_mapped)
atmel_spi_dma_unmap_xfer(master, xfer);
if (xfer->delay_usecs)
udelay(xfer->delay_usecs);
if (atmel_spi_xfer_is_last(msg, xfer) || as->done_status < 0) {
/* report completed (or erroneous) message */
atmel_spi_msg_done(master, as, msg, xfer->cs_change);
} else {
if (xfer->cs_change) {
cs_deactivate(as, msg->spi);
udelay(1);
cs_activate(as, msg->spi);
}
/*
* Not done yet. Submit the next transfer.
*
* FIXME handle protocol options for xfer
*/
atmel_spi_dma_next_xfer(master, msg);
}
} else {
/*
* Keep going, we still have data to send in
* the current transfer.
*/
atmel_spi_dma_next_xfer(master, msg);
}
tasklet_out:
atmel_spi_unlock(as);
} }
/* Interrupt /* Interrupt
* *
* No need for locking in this Interrupt handler: done_status is the * No need for locking in this Interrupt handler: done_status is the
* only information modified. What we need is the update of this field * only information modified.
* before tasklet runs. This is ensured by using barrier.
*/ */
static irqreturn_t static irqreturn_t
atmel_spi_pio_interrupt(int irq, void *dev_id) atmel_spi_pio_interrupt(int irq, void *dev_id)
@ -1158,8 +913,6 @@ atmel_spi_pio_interrupt(int irq, void *dev_id)
* *
* We will also not process any remaning transfers in * We will also not process any remaning transfers in
* the message. * the message.
*
* All actions are done in tasklet with done_status indication
*/ */
as->done_status = -EIO; as->done_status = -EIO;
smp_wmb(); smp_wmb();
@ -1167,7 +920,7 @@ atmel_spi_pio_interrupt(int irq, void *dev_id)
/* Clear any overrun happening while cleaning up */ /* Clear any overrun happening while cleaning up */
spi_readl(as, SR); spi_readl(as, SR);
tasklet_schedule(&as->tasklet); complete(&as->xfer_completion);
} else if (pending & SPI_BIT(RDRF)) { } else if (pending & SPI_BIT(RDRF)) {
atmel_spi_lock(as); atmel_spi_lock(as);
@ -1176,11 +929,10 @@ atmel_spi_pio_interrupt(int irq, void *dev_id)
ret = IRQ_HANDLED; ret = IRQ_HANDLED;
xfer = as->current_transfer; xfer = as->current_transfer;
atmel_spi_pump_pio_data(as, xfer); atmel_spi_pump_pio_data(as, xfer);
if (!as->current_remaining_bytes) { if (!as->current_remaining_bytes)
/* no more data to xfer, kick tasklet */
spi_writel(as, IDR, pending); spi_writel(as, IDR, pending);
tasklet_schedule(&as->tasklet);
} complete(&as->xfer_completion);
} }
atmel_spi_unlock(as); atmel_spi_unlock(as);
@ -1198,116 +950,35 @@ atmel_spi_pdc_interrupt(int irq, void *dev_id)
{ {
struct spi_master *master = dev_id; struct spi_master *master = dev_id;
struct atmel_spi *as = spi_master_get_devdata(master); struct atmel_spi *as = spi_master_get_devdata(master);
struct spi_message *msg;
struct spi_transfer *xfer;
u32 status, pending, imr; u32 status, pending, imr;
int ret = IRQ_NONE; int ret = IRQ_NONE;
atmel_spi_lock(as);
xfer = as->current_transfer;
msg = list_entry(as->queue.next, struct spi_message, queue);
imr = spi_readl(as, IMR); imr = spi_readl(as, IMR);
status = spi_readl(as, SR); status = spi_readl(as, SR);
pending = status & imr; pending = status & imr;
if (pending & SPI_BIT(OVRES)) { if (pending & SPI_BIT(OVRES)) {
int timeout;
ret = IRQ_HANDLED; ret = IRQ_HANDLED;
spi_writel(as, IDR, (SPI_BIT(RXBUFF) | SPI_BIT(ENDRX) spi_writel(as, IDR, (SPI_BIT(RXBUFF) | SPI_BIT(ENDRX)
| SPI_BIT(OVRES))); | SPI_BIT(OVRES)));
/*
* When we get an overrun, we disregard the current
* transfer. Data will not be copied back from any
* bounce buffer and msg->actual_len will not be
* updated with the last xfer.
*
* We will also not process any remaning transfers in
* the message.
*
* First, stop the transfer and unmap the DMA buffers.
*/
spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS));
if (!msg->is_dma_mapped)
atmel_spi_dma_unmap_xfer(master, xfer);
/* REVISIT: udelay in irq is unfriendly */
if (xfer->delay_usecs)
udelay(xfer->delay_usecs);
dev_warn(master->dev.parent, "overrun (%u/%u remaining)\n",
spi_readl(as, TCR), spi_readl(as, RCR));
/*
* Clean up DMA registers and make sure the data
* registers are empty.
*/
spi_writel(as, RNCR, 0);
spi_writel(as, TNCR, 0);
spi_writel(as, RCR, 0);
spi_writel(as, TCR, 0);
for (timeout = 1000; timeout; timeout--)
if (spi_readl(as, SR) & SPI_BIT(TXEMPTY))
break;
if (!timeout)
dev_warn(master->dev.parent,
"timeout waiting for TXEMPTY");
while (spi_readl(as, SR) & SPI_BIT(RDRF))
spi_readl(as, RDR);
/* Clear any overrun happening while cleaning up */ /* Clear any overrun happening while cleaning up */
spi_readl(as, SR); spi_readl(as, SR);
as->done_status = -EIO; as->done_status = -EIO;
atmel_spi_msg_done(master, as, msg, 0);
complete(&as->xfer_completion);
} else if (pending & (SPI_BIT(RXBUFF) | SPI_BIT(ENDRX))) { } else if (pending & (SPI_BIT(RXBUFF) | SPI_BIT(ENDRX))) {
ret = IRQ_HANDLED; ret = IRQ_HANDLED;
spi_writel(as, IDR, pending); spi_writel(as, IDR, pending);
if (as->current_remaining_bytes == 0) { complete(&as->xfer_completion);
msg->actual_length += xfer->len;
if (!msg->is_dma_mapped)
atmel_spi_dma_unmap_xfer(master, xfer);
/* REVISIT: udelay in irq is unfriendly */
if (xfer->delay_usecs)
udelay(xfer->delay_usecs);
if (atmel_spi_xfer_is_last(msg, xfer)) {
/* report completed message */
atmel_spi_msg_done(master, as, msg,
xfer->cs_change);
} else {
if (xfer->cs_change) {
cs_deactivate(as, msg->spi);
udelay(1);
cs_activate(as, msg->spi);
}
/*
* Not done yet. Submit the next transfer.
*
* FIXME handle protocol options for xfer
*/
atmel_spi_pdc_next_xfer(master, msg);
}
} else {
/*
* Keep going, we still have data to send in
* the current transfer.
*/
atmel_spi_pdc_next_xfer(master, msg);
}
} }
atmel_spi_unlock(as);
return ret; return ret;
} }
@ -1322,9 +993,6 @@ static int atmel_spi_setup(struct spi_device *spi)
as = spi_master_get_devdata(spi->master); as = spi_master_get_devdata(spi->master);
if (as->stopping)
return -ESHUTDOWN;
if (spi->chip_select > spi->master->num_chipselect) { if (spi->chip_select > spi->master->num_chipselect) {
dev_dbg(&spi->dev, dev_dbg(&spi->dev,
"setup: invalid chipselect %u (%u defined)\n", "setup: invalid chipselect %u (%u defined)\n",
@ -1376,12 +1044,6 @@ static int atmel_spi_setup(struct spi_device *spi)
asd->npcs_pin = npcs_pin; asd->npcs_pin = npcs_pin;
spi->controller_state = asd; spi->controller_state = asd;
gpio_direction_output(npcs_pin, !(spi->mode & SPI_CS_HIGH)); gpio_direction_output(npcs_pin, !(spi->mode & SPI_CS_HIGH));
} else {
atmel_spi_lock(as);
if (as->stay == spi)
as->stay = NULL;
cs_deactivate(as, spi);
atmel_spi_unlock(as);
} }
asd->csr = csr; asd->csr = csr;
@ -1396,97 +1058,218 @@ static int atmel_spi_setup(struct spi_device *spi)
return 0; return 0;
} }
static int atmel_spi_transfer(struct spi_device *spi, struct spi_message *msg) static int atmel_spi_one_transfer(struct spi_master *master,
struct spi_message *msg,
struct spi_transfer *xfer)
{ {
struct atmel_spi *as; struct atmel_spi *as;
struct spi_transfer *xfer; struct spi_device *spi = msg->spi;
struct device *controller = spi->master->dev.parent;
u8 bits; u8 bits;
u32 len;
struct atmel_spi_device *asd; struct atmel_spi_device *asd;
int timeout;
int ret;
as = spi_master_get_devdata(spi->master); as = spi_master_get_devdata(master);
dev_dbg(controller, "new message %p submitted for %s\n", if (!(xfer->tx_buf || xfer->rx_buf) && xfer->len) {
msg, dev_name(&spi->dev)); dev_dbg(&spi->dev, "missing rx or tx buf\n");
return -EINVAL;
}
if (xfer->bits_per_word) {
asd = spi->controller_state;
bits = (asd->csr >> 4) & 0xf;
if (bits != xfer->bits_per_word - 8) {
dev_dbg(&spi->dev,
"you can't yet change bits_per_word in transfers\n");
return -ENOPROTOOPT;
}
}
if (xfer->bits_per_word > 8) {
if (xfer->len % 2) {
dev_dbg(&spi->dev,
"buffer len should be 16 bits aligned\n");
return -EINVAL;
}
}
/*
* DMA map early, for performance (empties dcache ASAP) and
* better fault reporting.
*/
if ((!msg->is_dma_mapped)
&& (atmel_spi_use_dma(as, xfer) || as->use_pdc)) {
if (atmel_spi_dma_map_xfer(as, xfer) < 0)
return -ENOMEM;
}
atmel_spi_set_xfer_speed(as, msg->spi, xfer);
as->done_status = 0;
as->current_transfer = xfer;
as->current_remaining_bytes = xfer->len;
while (as->current_remaining_bytes) {
reinit_completion(&as->xfer_completion);
if (as->use_pdc) {
atmel_spi_pdc_next_xfer(master, msg, xfer);
} else if (atmel_spi_use_dma(as, xfer)) {
len = as->current_remaining_bytes;
ret = atmel_spi_next_xfer_dma_submit(master,
xfer, &len);
if (ret) {
dev_err(&spi->dev,
"unable to use DMA, fallback to PIO\n");
atmel_spi_next_xfer_pio(master, xfer);
} else {
as->current_remaining_bytes -= len;
}
} else {
atmel_spi_next_xfer_pio(master, xfer);
}
ret = wait_for_completion_timeout(&as->xfer_completion,
SPI_DMA_TIMEOUT);
if (WARN_ON(ret == 0)) {
dev_err(&spi->dev,
"spi trasfer timeout, err %d\n", ret);
as->done_status = -EIO;
} else {
ret = 0;
}
if (as->done_status)
break;
}
if (as->done_status) {
if (as->use_pdc) {
dev_warn(master->dev.parent,
"overrun (%u/%u remaining)\n",
spi_readl(as, TCR), spi_readl(as, RCR));
/*
* Clean up DMA registers and make sure the data
* registers are empty.
*/
spi_writel(as, RNCR, 0);
spi_writel(as, TNCR, 0);
spi_writel(as, RCR, 0);
spi_writel(as, TCR, 0);
for (timeout = 1000; timeout; timeout--)
if (spi_readl(as, SR) & SPI_BIT(TXEMPTY))
break;
if (!timeout)
dev_warn(master->dev.parent,
"timeout waiting for TXEMPTY");
while (spi_readl(as, SR) & SPI_BIT(RDRF))
spi_readl(as, RDR);
/* Clear any overrun happening while cleaning up */
spi_readl(as, SR);
} else if (atmel_spi_use_dma(as, xfer)) {
atmel_spi_stop_dma(as);
}
if (!msg->is_dma_mapped
&& (atmel_spi_use_dma(as, xfer) || as->use_pdc))
atmel_spi_dma_unmap_xfer(master, xfer);
return 0;
} else {
/* only update length if no error */
msg->actual_length += xfer->len;
}
if (!msg->is_dma_mapped
&& (atmel_spi_use_dma(as, xfer) || as->use_pdc))
atmel_spi_dma_unmap_xfer(master, xfer);
if (xfer->delay_usecs)
udelay(xfer->delay_usecs);
if (xfer->cs_change) {
if (list_is_last(&xfer->transfer_list,
&msg->transfers)) {
as->keep_cs = true;
} else {
as->cs_active = !as->cs_active;
if (as->cs_active)
cs_activate(as, msg->spi);
else
cs_deactivate(as, msg->spi);
}
}
return 0;
}
static int atmel_spi_transfer_one_message(struct spi_master *master,
struct spi_message *msg)
{
struct atmel_spi *as;
struct spi_transfer *xfer;
struct spi_device *spi = msg->spi;
int ret = 0;
as = spi_master_get_devdata(master);
dev_dbg(&spi->dev, "new message %p submitted for %s\n",
msg, dev_name(&spi->dev));
if (unlikely(list_empty(&msg->transfers))) if (unlikely(list_empty(&msg->transfers)))
return -EINVAL; return -EINVAL;
if (as->stopping) atmel_spi_lock(as);
return -ESHUTDOWN; cs_activate(as, spi);
as->cs_active = true;
as->keep_cs = false;
msg->status = 0;
msg->actual_length = 0;
list_for_each_entry(xfer, &msg->transfers, transfer_list) { list_for_each_entry(xfer, &msg->transfers, transfer_list) {
if (!(xfer->tx_buf || xfer->rx_buf) && xfer->len) { ret = atmel_spi_one_transfer(master, msg, xfer);
dev_dbg(&spi->dev, "missing rx or tx buf\n"); if (ret)
return -EINVAL; goto msg_done;
}
if (xfer->bits_per_word) {
asd = spi->controller_state;
bits = (asd->csr >> 4) & 0xf;
if (bits != xfer->bits_per_word - 8) {
dev_dbg(&spi->dev,
"you can't yet change bits_per_word in transfers\n");
return -ENOPROTOOPT;
}
}
if (xfer->bits_per_word > 8) {
if (xfer->len % 2) {
dev_dbg(&spi->dev, "buffer len should be 16 bits aligned\n");
return -EINVAL;
}
}
/*
* DMA map early, for performance (empties dcache ASAP) and
* better fault reporting.
*/
if ((!msg->is_dma_mapped) && (atmel_spi_use_dma(as, xfer)
|| as->use_pdc)) {
if (atmel_spi_dma_map_xfer(as, xfer) < 0)
return -ENOMEM;
}
} }
#ifdef VERBOSE if (as->use_pdc)
atmel_spi_disable_pdc_transfer(as);
list_for_each_entry(xfer, &msg->transfers, transfer_list) { list_for_each_entry(xfer, &msg->transfers, transfer_list) {
dev_dbg(controller, dev_dbg(&spi->dev,
" xfer %p: len %u tx %p/%08x rx %p/%08x\n", " xfer %p: len %u tx %p/%08x rx %p/%08x\n",
xfer, xfer->len, xfer, xfer->len,
xfer->tx_buf, xfer->tx_dma, xfer->tx_buf, xfer->tx_dma,
xfer->rx_buf, xfer->rx_dma); xfer->rx_buf, xfer->rx_dma);
} }
#endif
msg->status = -EINPROGRESS; msg_done:
msg->actual_length = 0; if (!as->keep_cs)
cs_deactivate(as, msg->spi);
atmel_spi_lock(as);
list_add_tail(&msg->queue, &as->queue);
if (!as->current_transfer)
atmel_spi_next_message(spi->master);
atmel_spi_unlock(as); atmel_spi_unlock(as);
return 0; msg->status = as->done_status;
spi_finalize_current_message(spi->master);
return ret;
} }
static void atmel_spi_cleanup(struct spi_device *spi) static void atmel_spi_cleanup(struct spi_device *spi)
{ {
struct atmel_spi *as = spi_master_get_devdata(spi->master);
struct atmel_spi_device *asd = spi->controller_state; struct atmel_spi_device *asd = spi->controller_state;
unsigned gpio = (unsigned) spi->controller_data; unsigned gpio = (unsigned) spi->controller_data;
if (!asd) if (!asd)
return; return;
atmel_spi_lock(as);
if (as->stay == spi) {
as->stay = NULL;
cs_deactivate(as, spi);
}
atmel_spi_unlock(as);
spi->controller_state = NULL; spi->controller_state = NULL;
gpio_free(gpio); gpio_free(gpio);
kfree(asd); kfree(asd);
@ -1545,7 +1328,7 @@ static int atmel_spi_probe(struct platform_device *pdev)
master->bus_num = pdev->id; master->bus_num = pdev->id;
master->num_chipselect = master->dev.of_node ? 0 : 4; master->num_chipselect = master->dev.of_node ? 0 : 4;
master->setup = atmel_spi_setup; master->setup = atmel_spi_setup;
master->transfer = atmel_spi_transfer; master->transfer_one_message = atmel_spi_transfer_one_message;
master->cleanup = atmel_spi_cleanup; master->cleanup = atmel_spi_cleanup;
platform_set_drvdata(pdev, master); platform_set_drvdata(pdev, master);
@ -1561,7 +1344,6 @@ static int atmel_spi_probe(struct platform_device *pdev)
goto out_free; goto out_free;
spin_lock_init(&as->lock); spin_lock_init(&as->lock);
INIT_LIST_HEAD(&as->queue);
as->pdev = pdev; as->pdev = pdev;
as->regs = devm_ioremap_resource(&pdev->dev, regs); as->regs = devm_ioremap_resource(&pdev->dev, regs);
@ -1573,6 +1355,8 @@ static int atmel_spi_probe(struct platform_device *pdev)
as->irq = irq; as->irq = irq;
as->clk = clk; as->clk = clk;
init_completion(&as->xfer_completion);
atmel_get_caps(as); atmel_get_caps(as);
as->use_dma = false; as->use_dma = false;
@ -1591,9 +1375,6 @@ static int atmel_spi_probe(struct platform_device *pdev)
ret = devm_request_irq(&pdev->dev, irq, atmel_spi_pdc_interrupt, ret = devm_request_irq(&pdev->dev, irq, atmel_spi_pdc_interrupt,
0, dev_name(&pdev->dev), master); 0, dev_name(&pdev->dev), master);
} else { } else {
tasklet_init(&as->tasklet, atmel_spi_tasklet_func,
(unsigned long)master);
ret = devm_request_irq(&pdev->dev, irq, atmel_spi_pio_interrupt, ret = devm_request_irq(&pdev->dev, irq, atmel_spi_pio_interrupt,
0, dev_name(&pdev->dev), master); 0, dev_name(&pdev->dev), master);
} }
@ -1637,8 +1418,6 @@ static int atmel_spi_probe(struct platform_device *pdev)
out_free_irq: out_free_irq:
out_unmap_regs: out_unmap_regs:
out_free_buffer: out_free_buffer:
if (!as->use_pdc)
tasklet_kill(&as->tasklet);
dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer, dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer,
as->buffer_dma); as->buffer_dma);
out_free: out_free:
@ -1650,12 +1429,9 @@ static int atmel_spi_remove(struct platform_device *pdev)
{ {
struct spi_master *master = platform_get_drvdata(pdev); struct spi_master *master = platform_get_drvdata(pdev);
struct atmel_spi *as = spi_master_get_devdata(master); struct atmel_spi *as = spi_master_get_devdata(master);
struct spi_message *msg;
struct spi_transfer *xfer;
/* reset the hardware and block queue progress */ /* reset the hardware and block queue progress */
spin_lock_irq(&as->lock); spin_lock_irq(&as->lock);
as->stopping = 1;
if (as->use_dma) { if (as->use_dma) {
atmel_spi_stop_dma(as); atmel_spi_stop_dma(as);
atmel_spi_release_dma(as); atmel_spi_release_dma(as);
@ -1666,20 +1442,6 @@ static int atmel_spi_remove(struct platform_device *pdev)
spi_readl(as, SR); spi_readl(as, SR);
spin_unlock_irq(&as->lock); spin_unlock_irq(&as->lock);
/* Terminate remaining queued transfers */
list_for_each_entry(msg, &as->queue, queue) {
list_for_each_entry(xfer, &msg->transfers, transfer_list) {
if (!msg->is_dma_mapped
&& (atmel_spi_use_dma(as, xfer)
|| as->use_pdc))
atmel_spi_dma_unmap_xfer(master, xfer);
}
msg->status = -ESHUTDOWN;
msg->complete(msg->context);
}
if (!as->use_pdc)
tasklet_kill(&as->tasklet);
dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer, dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer,
as->buffer_dma); as->buffer_dma);