spi: dw-mid: move to use core SPI DMA mappings

SPI core has a comprehensive function set to map and unmap a message when it's
needed. This patch converts driver to use that advantage.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-dw-mid.c b/drivers/spi/spi-dw-mid.c
index e614190..599dad4 100644 (file)
--- a/drivers/spi/spi-dw-mid.c
+++ b/drivers/spi/spi-dw-mid.c
@@ -69,6 +69,7 @@ static int mid_spi_dma_init(struct dw_spi *dws)
        rxs->hs_mode = LNW_DMA_HW_HS;
        rxs->cfg_mode = LNW_DMA_PER_TO_MEM;
        dws->rxchan->private = rxs;
+       dws->master->dma_rx = dws->rxchan;
 
        /* 2. Init tx channel */
        dws->txchan = dma_request_channel(mask, mid_spi_dma_chan_filter, dws);
@@ -78,6 +79,7 @@ static int mid_spi_dma_init(struct dw_spi *dws)
        txs->hs_mode = LNW_DMA_HW_HS;
        txs->cfg_mode = LNW_DMA_MEM_TO_PER;
        dws->txchan->private = txs;
+       dws->master->dma_tx = dws->txchan;
 
        dws->dma_inited = 1;
        return 0;
@@ -116,6 +118,17 @@ static irqreturn_t dma_transfer(struct dw_spi *dws)
        return IRQ_HANDLED;
 }
 
+static bool mid_spi_can_dma(struct spi_master *master, struct spi_device *spi,
+               struct spi_transfer *xfer)
+{
+       struct dw_spi *dws = spi_master_get_devdata(master);
+
+       if (!dws->dma_inited)
+               return false;
+
+       return xfer->len > dws->fifo_len;
+}
+
 static enum dma_slave_buswidth convert_dma_width(u32 dma_width) {
        if (dma_width == 1)
                return DMA_SLAVE_BUSWIDTH_1_BYTE;
@@ -139,12 +152,13 @@ static void dw_spi_dma_tx_done(void *arg)
        spi_finalize_current_transfer(dws->master);
 }
 
-static struct dma_async_tx_descriptor *dw_spi_dma_prepare_tx(struct dw_spi *dws)
+static struct dma_async_tx_descriptor *dw_spi_dma_prepare_tx(struct dw_spi *dws,
+               struct spi_transfer *xfer)
 {
        struct dma_slave_config txconf;
        struct dma_async_tx_descriptor *txdesc;
 
-       if (!dws->tx_dma)
+       if (!xfer->tx_buf)
                return NULL;
 
        txconf.direction = DMA_MEM_TO_DEV;
@@ -156,13 +170,9 @@ static struct dma_async_tx_descriptor *dw_spi_dma_prepare_tx(struct dw_spi *dws)
 
        dmaengine_slave_config(dws->txchan, &txconf);
 
-       memset(&dws->tx_sgl, 0, sizeof(dws->tx_sgl));
-       dws->tx_sgl.dma_address = dws->tx_dma;
-       dws->tx_sgl.length = dws->len;
-
        txdesc = dmaengine_prep_slave_sg(dws->txchan,
-                               &dws->tx_sgl,
-                               1,
+                               xfer->tx_sg.sgl,
+                               xfer->tx_sg.nents,
                                DMA_MEM_TO_DEV,
                                DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
        if (!txdesc)
@@ -188,12 +198,13 @@ static void dw_spi_dma_rx_done(void *arg)
        spi_finalize_current_transfer(dws->master);
 }
 
-static struct dma_async_tx_descriptor *dw_spi_dma_prepare_rx(struct dw_spi *dws)
+static struct dma_async_tx_descriptor *dw_spi_dma_prepare_rx(struct dw_spi *dws,
+               struct spi_transfer *xfer)
 {
        struct dma_slave_config rxconf;
        struct dma_async_tx_descriptor *rxdesc;
 
-       if (!dws->rx_dma)
+       if (!xfer->rx_buf)
                return NULL;
 
        rxconf.direction = DMA_DEV_TO_MEM;
@@ -205,13 +216,9 @@ static struct dma_async_tx_descriptor *dw_spi_dma_prepare_rx(struct dw_spi *dws)
 
        dmaengine_slave_config(dws->rxchan, &rxconf);
 
-       memset(&dws->rx_sgl, 0, sizeof(dws->rx_sgl));
-       dws->rx_sgl.dma_address = dws->rx_dma;
-       dws->rx_sgl.length = dws->len;
-
        rxdesc = dmaengine_prep_slave_sg(dws->rxchan,
-                               &dws->rx_sgl,
-                               1,
+                               xfer->rx_sg.sgl,
+                               xfer->rx_sg.nents,
                                DMA_DEV_TO_MEM,
                                DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
        if (!rxdesc)
@@ -223,16 +230,16 @@ static struct dma_async_tx_descriptor *dw_spi_dma_prepare_rx(struct dw_spi *dws)
        return rxdesc;
 }
 
-static int mid_spi_dma_setup(struct dw_spi *dws)
+static int mid_spi_dma_setup(struct dw_spi *dws, struct spi_transfer *xfer)
 {
        u16 dma_ctrl = 0;
 
        dw_writew(dws, DW_SPI_DMARDLR, 0xf);
        dw_writew(dws, DW_SPI_DMATDLR, 0x10);
 
-       if (dws->tx_dma)
+       if (xfer->tx_buf)
                dma_ctrl |= SPI_DMA_TDMAE;
-       if (dws->rx_dma)
+       if (xfer->rx_buf)
                dma_ctrl |= SPI_DMA_RDMAE;
        dw_writew(dws, DW_SPI_DMACR, dma_ctrl);
 
@@ -244,15 +251,15 @@ static int mid_spi_dma_setup(struct dw_spi *dws)
        return 0;
 }
 
-static int mid_spi_dma_transfer(struct dw_spi *dws)
+static int mid_spi_dma_transfer(struct dw_spi *dws, struct spi_transfer *xfer)
 {
        struct dma_async_tx_descriptor *txdesc, *rxdesc;
 
        /* Prepare the TX dma transfer */
-       txdesc = dw_spi_dma_prepare_tx(dws);
+       txdesc = dw_spi_dma_prepare_tx(dws, xfer);
 
        /* Prepare the RX dma transfer */
-       rxdesc = dw_spi_dma_prepare_rx(dws);
+       rxdesc = dw_spi_dma_prepare_rx(dws, xfer);
 
        /* rx must be started before tx due to spi instinct */
        if (rxdesc) {
@@ -286,6 +293,7 @@ static struct dw_spi_dma_ops mid_dma_ops = {
        .dma_init       = mid_spi_dma_init,
        .dma_exit       = mid_spi_dma_exit,
        .dma_setup      = mid_spi_dma_setup,
+       .can_dma        = mid_spi_can_dma,
        .dma_transfer   = mid_spi_dma_transfer,
        .dma_stop       = mid_spi_dma_stop,
 };

diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c
index d53cffe..2437bfc 100644 (file)
--- a/drivers/spi/spi-dw.c
+++ b/drivers/spi/spi-dw.c
@@ -217,32 +217,6 @@ static void dw_reader(struct dw_spi *dws)
        }
 }
 
-/*
- * Note: first step is the protocol driver prepares
- * a dma-capable memory, and this func just need translate
- * the virt addr to physical
- */
-static int map_dma_buffers(struct spi_master *master,
-               struct spi_device *spi, struct spi_transfer *transfer)
-{
-       struct dw_spi *dws = spi_master_get_devdata(master);
-       struct chip_data *chip = spi_get_ctldata(spi);
-
-       if (!master->cur_msg->is_dma_mapped
-               || !dws->dma_inited
-               || !chip->enable_dma
-               || !dws->dma_ops)
-               return 0;
-
-       if (transfer->tx_dma)
-               dws->tx_dma = transfer->tx_dma;
-
-       if (transfer->rx_dma)
-               dws->rx_dma = transfer->rx_dma;
-
-       return 1;
-}
-
 static void int_error_stop(struct dw_spi *dws, const char *msg)
 {
        spi_reset_chip(dws);
@@ -322,11 +296,10 @@ static int dw_spi_transfer_one(struct spi_master *master,
        u32 cr0 = 0;
        int ret;
 
+       dws->dma_mapped = 0;
        dws->n_bytes = chip->n_bytes;
        dws->dma_width = chip->dma_width;
 
-       dws->rx_dma = transfer->rx_dma;
-       dws->tx_dma = transfer->tx_dma;
        dws->tx = (void *)transfer->tx_buf;
        dws->tx_end = dws->tx + transfer->len;
        dws->rx = transfer->rx_buf;
@@ -386,7 +359,8 @@ static int dw_spi_transfer_one(struct spi_master *master,
        dw_writew(dws, DW_SPI_CTRL0, cr0);
 
        /* Check if current transfer is a DMA transaction */
-       dws->dma_mapped = map_dma_buffers(master, spi, transfer);
+       if (master->can_dma && master->can_dma(master, spi, transfer))
+               dws->dma_mapped = master->cur_msg_mapped;
 
        /* For poll mode just disable all interrupts */
        spi_mask_intr(dws, 0xff);
@@ -396,7 +370,7 @@ static int dw_spi_transfer_one(struct spi_master *master,
         * we only need set the TXEI IRQ, as TX/RX always happen syncronizely
         */
        if (dws->dma_mapped) {
-               ret = dws->dma_ops->dma_setup(dws);
+               ret = dws->dma_ops->dma_setup(dws, transfer);
                if (ret < 0) {
                        spi_enable_chip(dws, 1);
                        return ret;
@@ -416,7 +390,7 @@ static int dw_spi_transfer_one(struct spi_master *master,
        spi_enable_chip(dws, 1);
 
        if (dws->dma_mapped) {
-               ret = dws->dma_ops->dma_transfer(dws);
+               ret = dws->dma_ops->dma_transfer(dws, transfer);
                if (ret < 0)
                        return ret;
        }
@@ -470,8 +444,6 @@ static int dw_spi_setup(struct spi_device *spi)
 
                chip->rx_threshold = 0;
                chip->tx_threshold = 0;
-
-               chip->enable_dma = chip_info->enable_dma;
        }
 
        if (spi->bits_per_word == 8) {
@@ -584,6 +556,8 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws)
                if (ret) {
                        dev_warn(dev, "DMA init failed\n");
                        dws->dma_inited = 0;
+               } else {
+                       master->can_dma = dws->dma_ops->can_dma;
                }
        }
 

diff --git a/drivers/spi/spi-dw.h b/drivers/spi/spi-dw.h
index 7f130bd..f298df5 100644 (file)
--- a/drivers/spi/spi-dw.h
+++ b/drivers/spi/spi-dw.h
@@ -91,8 +91,10 @@ struct dw_spi;
 struct dw_spi_dma_ops {
        int (*dma_init)(struct dw_spi *dws);
        void (*dma_exit)(struct dw_spi *dws);
-       int (*dma_setup)(struct dw_spi *dws);
-       int (*dma_transfer)(struct dw_spi *dws);
+       int (*dma_setup)(struct dw_spi *dws, struct spi_transfer *xfer);
+       bool (*can_dma)(struct spi_master *master, struct spi_device *spi,
+                       struct spi_transfer *xfer);
+       int (*dma_transfer)(struct dw_spi *dws, struct spi_transfer *xfer);
        void (*dma_stop)(struct dw_spi *dws);
 };
 
@@ -117,20 +119,14 @@ struct dw_spi {
        void                    *rx;
        void                    *rx_end;
        int                     dma_mapped;
-       dma_addr_t              rx_dma;
-       dma_addr_t              tx_dma;
-       size_t                  rx_map_len;
-       size_t                  tx_map_len;
        u8                      n_bytes;        /* current is a 1/2 bytes op */
        u32                     dma_width;
        irqreturn_t             (*transfer_handler)(struct dw_spi *dws);
 
-       /* Dma info */
+       /* DMA info */
        int                     dma_inited;
        struct dma_chan         *txchan;
-       struct scatterlist      tx_sgl;
        struct dma_chan         *rxchan;
-       struct scatterlist      rx_sgl;
        unsigned long           dma_chan_busy;
        struct device           *dma_dev;
        dma_addr_t              dma_addr; /* phy address of the Data register */
@@ -206,14 +202,13 @@ static inline void spi_reset_chip(struct dw_spi *dws)
 
 /*
  * Each SPI slave device to work with dw_api controller should
- * has such a structure claiming its working mode (PIO/DMA etc),
+ * has such a structure claiming its working mode (poll or PIO/DMA),
  * which can be save in the "controller_data" member of the
  * struct spi_device.
  */
 struct dw_spi_chip {
        u8 poll_mode;   /* 1 for controller polling mode */
        u8 type;        /* SPI/SSP/MicroWire */
-       u8 enable_dma;
        void (*cs_control)(u32 command);
 };