spi: pxa2xx: Switch to SPI core DMA mapping functionality
SPI core provides DMA mapping with scatterlists. Start using it instead
of own implementation in spi-pxa2xx. Major difference in addition to
bunch of removed boilerplate code is that SPI core does
mapping/unmapping for all transfers in a message before and after the
message sending where spi-pxa2xx did mapping/unmapping for each
transfers separately.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/spi/spi-pxa2xx-dma.c b/drivers/spi/spi-pxa2xx-dma.c
index a18a03d..db3ae1d 100644
--- a/drivers/spi/spi-pxa2xx-dma.c
+++ b/drivers/spi/spi-pxa2xx-dma.c
@@ -20,79 +20,6 @@
#include "spi-pxa2xx.h"
-static int pxa2xx_spi_map_dma_buffer(struct driver_data *drv_data,
- enum dma_data_direction dir)
-{
- int i, nents, len = drv_data->len;
- struct scatterlist *sg;
- struct device *dmadev;
- struct sg_table *sgt;
- void *buf, *pbuf;
-
- if (dir == DMA_TO_DEVICE) {
- dmadev = drv_data->tx_chan->device->dev;
- sgt = &drv_data->tx_sgt;
- buf = drv_data->tx;
- } else {
- dmadev = drv_data->rx_chan->device->dev;
- sgt = &drv_data->rx_sgt;
- buf = drv_data->rx;
- }
-
- nents = DIV_ROUND_UP(len, SZ_2K);
- if (nents != sgt->nents) {
- int ret;
-
- sg_free_table(sgt);
- ret = sg_alloc_table(sgt, nents, GFP_ATOMIC);
- if (ret)
- return ret;
- }
-
- pbuf = buf;
- for_each_sg(sgt->sgl, sg, sgt->nents, i) {
- size_t bytes = min_t(size_t, len, SZ_2K);
-
- sg_set_buf(sg, pbuf, bytes);
- pbuf += bytes;
- len -= bytes;
- }
-
- nents = dma_map_sg(dmadev, sgt->sgl, sgt->nents, dir);
- if (!nents)
- return -ENOMEM;
-
- return nents;
-}
-
-static void pxa2xx_spi_unmap_dma_buffer(struct driver_data *drv_data,
- enum dma_data_direction dir)
-{
- struct device *dmadev;
- struct sg_table *sgt;
-
- if (dir == DMA_TO_DEVICE) {
- dmadev = drv_data->tx_chan->device->dev;
- sgt = &drv_data->tx_sgt;
- } else {
- dmadev = drv_data->rx_chan->device->dev;
- sgt = &drv_data->rx_sgt;
- }
-
- dma_unmap_sg(dmadev, sgt->sgl, sgt->nents, dir);
-}
-
-static void pxa2xx_spi_unmap_dma_buffers(struct driver_data *drv_data)
-{
- if (!drv_data->dma_mapped)
- return;
-
- pxa2xx_spi_unmap_dma_buffer(drv_data, DMA_FROM_DEVICE);
- pxa2xx_spi_unmap_dma_buffer(drv_data, DMA_TO_DEVICE);
-
- drv_data->dma_mapped = 0;
-}
-
static void pxa2xx_spi_dma_transfer_complete(struct driver_data *drv_data,
bool error)
{
@@ -125,8 +52,6 @@
pxa2xx_spi_write(drv_data, SSTO, 0);
if (!error) {
- pxa2xx_spi_unmap_dma_buffers(drv_data);
-
msg->actual_length += drv_data->len;
msg->state = pxa2xx_spi_next_transfer(drv_data);
} else {
@@ -152,11 +77,12 @@
enum dma_transfer_direction dir)
{
struct chip_data *chip = drv_data->cur_chip;
+ struct spi_transfer *xfer = drv_data->cur_transfer;
enum dma_slave_buswidth width;
struct dma_slave_config cfg;
struct dma_chan *chan;
struct sg_table *sgt;
- int nents, ret;
+ int ret;
switch (drv_data->n_bytes) {
case 1:
@@ -178,17 +104,15 @@
cfg.dst_addr_width = width;
cfg.dst_maxburst = chip->dma_burst_size;
- sgt = &drv_data->tx_sgt;
- nents = drv_data->tx_nents;
- chan = drv_data->tx_chan;
+ sgt = &xfer->tx_sg;
+ chan = drv_data->master->dma_tx;
} else {
cfg.src_addr = drv_data->ssdr_physical;
cfg.src_addr_width = width;
cfg.src_maxburst = chip->dma_burst_size;
- sgt = &drv_data->rx_sgt;
- nents = drv_data->rx_nents;
- chan = drv_data->rx_chan;
+ sgt = &xfer->rx_sg;
+ chan = drv_data->master->dma_rx;
}
ret = dmaengine_slave_config(chan, &cfg);
@@ -197,46 +121,10 @@
return NULL;
}
- return dmaengine_prep_slave_sg(chan, sgt->sgl, nents, dir,
+ return dmaengine_prep_slave_sg(chan, sgt->sgl, sgt->nents, dir,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
}
-bool pxa2xx_spi_dma_is_possible(size_t len)
-{
- return len <= MAX_DMA_LEN;
-}
-
-int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data)
-{
- const struct chip_data *chip = drv_data->cur_chip;
- int ret;
-
- if (!chip->enable_dma)
- return 0;
-
- /* Don't bother with DMA if we can't do even a single burst */
- if (drv_data->len < chip->dma_burst_size)
- return 0;
-
- ret = pxa2xx_spi_map_dma_buffer(drv_data, DMA_TO_DEVICE);
- if (ret <= 0) {
- dev_warn(&drv_data->pdev->dev, "failed to DMA map TX\n");
- return 0;
- }
-
- drv_data->tx_nents = ret;
-
- ret = pxa2xx_spi_map_dma_buffer(drv_data, DMA_FROM_DEVICE);
- if (ret <= 0) {
- pxa2xx_spi_unmap_dma_buffer(drv_data, DMA_TO_DEVICE);
- dev_warn(&drv_data->pdev->dev, "failed to DMA map RX\n");
- return 0;
- }
-
- drv_data->rx_nents = ret;
- return 1;
-}
-
irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data)
{
u32 status;
@@ -245,8 +133,8 @@
if (status & SSSR_ROR) {
dev_err(&drv_data->pdev->dev, "FIFO overrun\n");
- dmaengine_terminate_async(drv_data->rx_chan);
- dmaengine_terminate_async(drv_data->tx_chan);
+ dmaengine_terminate_async(drv_data->master->dma_rx);
+ dmaengine_terminate_async(drv_data->master->dma_tx);
pxa2xx_spi_dma_transfer_complete(drv_data, true);
return IRQ_HANDLED;
@@ -285,16 +173,15 @@
return 0;
err_rx:
- dmaengine_terminate_async(drv_data->tx_chan);
+ dmaengine_terminate_async(drv_data->master->dma_tx);
err_tx:
- pxa2xx_spi_unmap_dma_buffers(drv_data);
return err;
}
void pxa2xx_spi_dma_start(struct driver_data *drv_data)
{
- dma_async_issue_pending(drv_data->rx_chan);
- dma_async_issue_pending(drv_data->tx_chan);
+ dma_async_issue_pending(drv_data->master->dma_rx);
+ dma_async_issue_pending(drv_data->master->dma_tx);
atomic_set(&drv_data->dma_running, 1);
}
@@ -303,21 +190,22 @@
{
struct pxa2xx_spi_master *pdata = drv_data->master_info;
struct device *dev = &drv_data->pdev->dev;
+ struct spi_master *master = drv_data->master;
dma_cap_mask_t mask;
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
- drv_data->tx_chan = dma_request_slave_channel_compat(mask,
+ master->dma_tx = dma_request_slave_channel_compat(mask,
pdata->dma_filter, pdata->tx_param, dev, "tx");
- if (!drv_data->tx_chan)
+ if (!master->dma_tx)
return -ENODEV;
- drv_data->rx_chan = dma_request_slave_channel_compat(mask,
+ master->dma_rx = dma_request_slave_channel_compat(mask,
pdata->dma_filter, pdata->rx_param, dev, "rx");
- if (!drv_data->rx_chan) {
- dma_release_channel(drv_data->tx_chan);
- drv_data->tx_chan = NULL;
+ if (!master->dma_rx) {
+ dma_release_channel(master->dma_tx);
+ master->dma_tx = NULL;
return -ENODEV;
}
@@ -326,17 +214,17 @@
void pxa2xx_spi_dma_release(struct driver_data *drv_data)
{
- if (drv_data->rx_chan) {
- dmaengine_terminate_sync(drv_data->rx_chan);
- dma_release_channel(drv_data->rx_chan);
- sg_free_table(&drv_data->rx_sgt);
- drv_data->rx_chan = NULL;
+ struct spi_master *master = drv_data->master;
+
+ if (master->dma_rx) {
+ dmaengine_terminate_sync(master->dma_rx);
+ dma_release_channel(master->dma_rx);
+ master->dma_rx = NULL;
}
- if (drv_data->tx_chan) {
- dmaengine_terminate_sync(drv_data->tx_chan);
- dma_release_channel(drv_data->tx_chan);
- sg_free_table(&drv_data->tx_sgt);
- drv_data->tx_chan = NULL;
+ if (master->dma_tx) {
+ dmaengine_terminate_sync(master->dma_tx);
+ dma_release_channel(master->dma_tx);
+ master->dma_tx = NULL;
}
}
diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c
index e5c457a..3e90a4c 100644
--- a/drivers/spi/spi-pxa2xx.c
+++ b/drivers/spi/spi-pxa2xx.c
@@ -912,6 +912,17 @@
return clk_div << 8;
}
+static bool pxa2xx_spi_can_dma(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ struct chip_data *chip = spi_get_ctldata(spi);
+
+ return chip->enable_dma &&
+ xfer->len <= MAX_DMA_LEN &&
+ xfer->len >= chip->dma_burst_size;
+}
+
static void pump_transfers(unsigned long data)
{
struct driver_data *drv_data = (struct driver_data *)data;
@@ -929,6 +940,7 @@
u32 dma_burst = drv_data->cur_chip->dma_burst_size;
u32 change_mask = pxa2xx_spi_get_ssrc1_change_mask(drv_data);
int err;
+ int dma_mapped;
/* Get current state information */
message = drv_data->cur_msg;
@@ -963,7 +975,7 @@
}
/* Check if we can DMA this transfer */
- if (!pxa2xx_spi_dma_is_possible(transfer->len) && chip->enable_dma) {
+ if (transfer->len > MAX_DMA_LEN && chip->enable_dma) {
/* reject already-mapped transfers; PIO won't always work */
if (message->is_dma_mapped
@@ -1040,10 +1052,10 @@
message->state = RUNNING_STATE;
- drv_data->dma_mapped = 0;
- if (pxa2xx_spi_dma_is_possible(drv_data->len))
- drv_data->dma_mapped = pxa2xx_spi_map_dma_buffers(drv_data);
- if (drv_data->dma_mapped) {
+ dma_mapped = master->can_dma &&
+ master->can_dma(master, message->spi, transfer) &&
+ master->cur_msg_mapped;
+ if (dma_mapped) {
/* Ensure we have the correct interrupt handler */
drv_data->transfer_handler = pxa2xx_spi_dma_transfer;
@@ -1075,12 +1087,12 @@
dev_dbg(&message->spi->dev, "%u Hz actual, %s\n",
master->max_speed_hz
/ (1 + ((cr0 & SSCR0_SCR(0xfff)) >> 8)),
- drv_data->dma_mapped ? "DMA" : "PIO");
+ dma_mapped ? "DMA" : "PIO");
else
dev_dbg(&message->spi->dev, "%u Hz actual, %s\n",
master->max_speed_hz / 2
/ (1 + ((cr0 & SSCR0_SCR(0x0ff)) >> 8)),
- drv_data->dma_mapped ? "DMA" : "PIO");
+ dma_mapped ? "DMA" : "PIO");
if (is_lpss_ssp(drv_data)) {
if ((pxa2xx_spi_read(drv_data, SSIRF) & 0xff)
@@ -1594,6 +1606,8 @@
if (status) {
dev_dbg(dev, "no DMA channels available, using PIO\n");
platform_info->enable_dma = false;
+ } else {
+ master->can_dma = pxa2xx_spi_can_dma;
}
}
diff --git a/drivers/spi/spi-pxa2xx.h b/drivers/spi/spi-pxa2xx.h
index e6b0900..d217ad5 100644
--- a/drivers/spi/spi-pxa2xx.h
+++ b/drivers/spi/spi-pxa2xx.h
@@ -50,12 +50,6 @@
struct tasklet_struct pump_transfers;
/* DMA engine support */
- struct dma_chan *rx_chan;
- struct dma_chan *tx_chan;
- struct sg_table rx_sgt;
- struct sg_table tx_sgt;
- int rx_nents;
- int tx_nents;
atomic_t dma_running;
/* Current message transfer state info */
@@ -67,7 +61,6 @@
void *tx_end;
void *rx;
void *rx_end;
- int dma_mapped;
u8 n_bytes;
int (*write)(struct driver_data *drv_data);
int (*read)(struct driver_data *drv_data);
@@ -145,8 +138,6 @@
#define MAX_DMA_LEN SZ_64K
#define DEFAULT_DMA_CR1 (SSCR1_TSRE | SSCR1_RSRE | SSCR1_TRAIL)
-extern bool pxa2xx_spi_dma_is_possible(size_t len);
-extern int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data);
extern irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data);
extern int pxa2xx_spi_dma_prepare(struct driver_data *drv_data, u32 dma_burst);
extern void pxa2xx_spi_dma_start(struct driver_data *drv_data);