diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 273db0b..b0842f7 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -189,6 +189,8 @@
*/
#define DMA_MIN_BYTES 16
+#define SPI_DMA_TIMEOUT (msecs_to_jiffies(1000))
+
struct atmel_spi_dma {
struct dma_chan *chan_rx;
struct dma_chan *chan_tx;
@@ -220,17 +222,13 @@ struct atmel_spi {
int irq;
struct clk *clk;
struct platform_device *pdev;
- struct spi_device *stay;
- u8 stopping;
- struct list_head queue;
- struct tasklet_struct tasklet;
struct spi_transfer *current_transfer;
unsigned long current_remaining_bytes;
- struct spi_transfer *next_transfer;
- unsigned long next_remaining_bytes;
int done_status;
+ struct completion xfer_completion;
+
/* scratch buffer */
void *buffer;
dma_addr_t buffer_dma;
@@ -241,6 +239,9 @@ struct atmel_spi {
bool use_pdc;
/* dmaengine data */
struct atmel_spi_dma dma;
+
+ bool keep_cs;
+ bool cs_active;
};
/* 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;
}
-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,
struct dma_slave_config *slave_config,
u8 bits_per_word)
@@ -513,23 +503,20 @@ static void dma_callback(void *data)
struct spi_master *master = data;
struct atmel_spi *as = spi_master_get_devdata(master);
- /* trigger SPI tasklet */
- tasklet_schedule(&as->tasklet);
+ complete(&as->xfer_completion);
}
/*
* Next transfer using PIO.
- * lock is held, spi tasklet is blocked
*/
static void atmel_spi_next_xfer_pio(struct spi_master *master,
struct spi_transfer *xfer)
{
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");
- as->current_remaining_bytes = xfer->len;
-
/* Make sure data is not remaining in RDR */
spi_readl(as, RDR);
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();
}
- if (xfer->tx_buf)
+ if (xfer->tx_buf) {
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
- spi_writel(as, TDR, *(u8 *)(xfer->tx_buf));
- else
+ spi_writel(as, TDR, *(u8 *)(xfer->tx_buf + xfer_pos));
+ } else {
spi_writel(as, TDR, 0);
+ }
dev_dbg(master->dev.parent,
" 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.
- * lock is held, spi tasklet is blocked
*/
static int atmel_spi_next_xfer_dma_submit(struct spi_master *master,
struct spi_transfer *xfer,
@@ -694,74 +681,90 @@ static void atmel_spi_next_xfer_data(struct spi_master *master,
*plen = len;
}
+static int atmel_spi_set_xfer_speed(struct atmel_spi *as,
+ struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ u32 scbr, csr;
+ unsigned long bus_hz;
+
+ /* v1 chips start out at half the peripheral bus speed. */
+ bus_hz = clk_get_rate(as->clk);
+ if (!atmel_spi_is_v2(as))
+ bus_hz /= 2;
+
+ /*
+ * Calculate the lowest divider that satisfies the
+ * constraint, assuming div32/fdiv/mbz == 0.
+ */
+ if (xfer->speed_hz)
+ scbr = DIV_ROUND_UP(bus_hz, xfer->speed_hz);
+ else
+ /*
+ * This can happend if max_speed is null.
+ * In this case, we set the lowest possible speed
+ */
+ scbr = 0xff;
+
+ /*
+ * If the resulting divider doesn't fit into the
+ * register bitfield, we can't satisfy the constraint.
+ */
+ if (scbr >= (1 << SPI_SCBR_SIZE)) {
+ dev_err(&spi->dev,
+ "setup: %d Hz too slow, scbr %u; min %ld Hz\n",
+ xfer->speed_hz, scbr, bus_hz/255);
+ return -EINVAL;
+ }
+ if (scbr == 0) {
+ dev_err(&spi->dev,
+ "setup: %d Hz too high, scbr %u; max %ld Hz\n",
+ xfer->speed_hz, scbr, bus_hz);
+ return -EINVAL;
+ }
+ csr = spi_readl(as, CSR0 + 4 * spi->chip_select);
+ csr = SPI_BFINS(SCBR, scbr, csr);
+ spi_writel(as, CSR0 + 4 * spi->chip_select, csr);
+
+ return 0;
+}
+
/*
* Submit next transfer for PDC.
* lock is held, spi irq is blocked
*/
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 spi_transfer *xfer;
- u32 len, remaining;
- u32 ieval;
+ u32 len;
dma_addr_t tx_dma, rx_dma;
- if (!as->current_transfer)
- 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) {
- spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS));
-
- len = xfer->len;
- atmel_spi_next_xfer_data(master, xfer, &tx_dma, &rx_dma, &len);
- remaining = xfer->len - 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);
- } else {
- xfer = as->next_transfer;
- remaining = as->next_remaining_bytes;
- }
+ spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS));
- as->current_transfer = xfer;
- as->current_remaining_bytes = remaining;
+ len = as->current_remaining_bytes;
+ atmel_spi_next_xfer_data(master, xfer, &tx_dma, &rx_dma, &len);
+ as->current_remaining_bytes -= len;
- 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;
+ spi_writel(as, RPR, rx_dma);
+ spi_writel(as, TPR, tx_dma);
- as->next_transfer = xfer;
+ if (msg->spi->bits_per_word > 8)
+ len >>= 1;
+ spi_writel(as, RCR, len);
+ spi_writel(as, TCR, len);
- if (xfer) {
- u32 total;
+ 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);
- total = len;
+ if (as->current_remaining_bytes) {
+ len = as->current_remaining_bytes;
atmel_spi_next_xfer_data(master, xfer, &tx_dma, &rx_dma, &len);
- as->next_remaining_bytes = total - len;
+ as->current_remaining_bytes -= len;
spi_writel(as, RNPR, rx_dma);
spi_writel(as, TNPR, tx_dma);
@@ -776,11 +779,6 @@ static void atmel_spi_pdc_next_xfer(struct spi_master *master,
xfer, xfer->len, xfer->tx_buf,
(unsigned long long)xfer->tx_dma, xfer->rx_buf,
(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
@@ -793,83 +791,11 @@ static void atmel_spi_pdc_next_xfer(struct spi_master *master,
*
* 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));
}
/*
- * 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;
- }
-
- 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:
* - The buffer is either valid for CPU access, else NULL
* - If the buffer is valid, so is its DMA address
@@ -924,41 +850,7 @@ static void atmel_spi_disable_pdc_transfer(struct atmel_spi *as)
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);