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>

1 files changed, 21 insertions, 7 deletions

diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c
index e5c457abb596..3e90a4ce668b 100644
--- a/drivers/spi/spi-pxa2xx.c
+++ b/drivers/spi/spi-pxa2xx.c
@@ -912,6 +912,17 @@ static unsigned int pxa2xx_ssp_get_clk_div(struct driver_data *drv_data,
         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 @@ static void pump_transfers(unsigned long data)
         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 @@ static void pump_transfers(unsigned long data)
         }
 
         /* 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 @@ static void pump_transfers(unsigned long data)
 
         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 @@ static void pump_transfers(unsigned long data)
                 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 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
                 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;
                 }
         }