]> git.kernelconcepts.de Git - karo-tx-linux.git/blobdiff - drivers/spi/spi-rspi.c
Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
[karo-tx-linux.git] / drivers / spi / spi-rspi.c
index 1fb0ad213324eadd2ef2a9cd9088880c42e5e722..10112745bb17fda624a6731cc907bbb26a48417e 100644 (file)
 #define SPBFCR_TXTRG_MASK      0x30    /* Transmit Buffer Data Triggering Number */
 #define SPBFCR_RXTRG_MASK      0x07    /* Receive Buffer Data Triggering Number */
 
-#define DUMMY_DATA             0x00
-
 struct rspi_data {
        void __iomem *addr;
        u32 max_speed_hz;
@@ -197,11 +195,6 @@ struct rspi_data {
        int rx_irq, tx_irq;
        const struct spi_ops *ops;
 
-       /* for dmaengine */
-       struct dma_chan *chan_tx;
-       struct dma_chan *chan_rx;
-
-       unsigned dma_width_16bit:1;
        unsigned dma_callbacked:1;
        unsigned byte_access:1;
 };
@@ -253,6 +246,8 @@ struct spi_ops {
        int (*transfer_one)(struct spi_master *master, struct spi_device *spi,
                            struct spi_transfer *xfer);
        u16 mode_bits;
+       u16 flags;
+       u16 fifo_size;
 };
 
 /*
@@ -266,7 +261,8 @@ static int rspi_set_config_register(struct rspi_data *rspi, int access_size)
        rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
 
        /* Sets transfer bit rate */
-       spbr = clk_get_rate(rspi->clk) / (2 * rspi->max_speed_hz) - 1;
+       spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk),
+                           2 * rspi->max_speed_hz) - 1;
        rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
 
        /* Disable dummy transmission, set 16-bit word access, 1 frame */
@@ -302,7 +298,8 @@ static int rspi_rz_set_config_register(struct rspi_data *rspi, int access_size)
        rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
 
        /* Sets transfer bit rate */
-       spbr = clk_get_rate(rspi->clk) / (2 * rspi->max_speed_hz) - 1;
+       spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk),
+                           2 * rspi->max_speed_hz) - 1;
        rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
 
        /* Disable dummy transmission, set byte access */
@@ -335,7 +332,7 @@ static int qspi_set_config_register(struct rspi_data *rspi, int access_size)
        rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
 
        /* Sets transfer bit rate */
-       spbr = clk_get_rate(rspi->clk) / (2 * rspi->max_speed_hz);
+       spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk), 2 * rspi->max_speed_hz);
        rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
 
        /* Disable dummy transmission, set byte access */
@@ -403,11 +400,22 @@ static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask,
        return 0;
 }
 
+static inline int rspi_wait_for_tx_empty(struct rspi_data *rspi)
+{
+       return rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
+}
+
+static inline int rspi_wait_for_rx_full(struct rspi_data *rspi)
+{
+       return rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE);
+}
+
 static int rspi_data_out(struct rspi_data *rspi, u8 data)
 {
-       if (rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE) < 0) {
+       int error = rspi_wait_for_tx_empty(rspi);
+       if (error < 0) {
                dev_err(&rspi->master->dev, "transmit timeout\n");
-               return -ETIMEDOUT;
+               return error;
        }
        rspi_write_data(rspi, data);
        return 0;
@@ -415,25 +423,36 @@ static int rspi_data_out(struct rspi_data *rspi, u8 data)
 
 static int rspi_data_in(struct rspi_data *rspi)
 {
+       int error;
        u8 data;
 
-       if (rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE) < 0) {
+       error = rspi_wait_for_rx_full(rspi);
+       if (error < 0) {
                dev_err(&rspi->master->dev, "receive timeout\n");
-               return -ETIMEDOUT;
+               return error;
        }
        data = rspi_read_data(rspi);
        return data;
 }
 
-static int rspi_data_out_in(struct rspi_data *rspi, u8 data)
+static int rspi_pio_transfer(struct rspi_data *rspi, const u8 *tx, u8 *rx,
+                            unsigned int n)
 {
-       int ret;
-
-       ret = rspi_data_out(rspi, data);
-       if (ret < 0)
-               return ret;
+       while (n-- > 0) {
+               if (tx) {
+                       int ret = rspi_data_out(rspi, *tx++);
+                       if (ret < 0)
+                               return ret;
+               }
+               if (rx) {
+                       int ret = rspi_data_in(rspi);
+                       if (ret < 0)
+                               return ret;
+                       *rx++ = ret;
+               }
+       }
 
-       return rspi_data_in(rspi);
+       return 0;
 }
 
 static void rspi_dma_complete(void *arg)
@@ -444,97 +463,67 @@ static void rspi_dma_complete(void *arg)
        wake_up_interruptible(&rspi->wait);
 }
 
-static int rspi_dma_map_sg(struct scatterlist *sg, const void *buf,
-                          unsigned len, struct dma_chan *chan,
-                          enum dma_transfer_direction dir)
-{
-       sg_init_table(sg, 1);
-       sg_set_buf(sg, buf, len);
-       sg_dma_len(sg) = len;
-       return dma_map_sg(chan->device->dev, sg, 1, dir);
-}
-
-static void rspi_dma_unmap_sg(struct scatterlist *sg, struct dma_chan *chan,
-                             enum dma_transfer_direction dir)
+static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
+                            struct sg_table *rx)
 {
-       dma_unmap_sg(chan->device->dev, sg, 1, dir);
-}
-
-static void rspi_memory_to_8bit(void *buf, const void *data, unsigned len)
-{
-       u16 *dst = buf;
-       const u8 *src = data;
-
-       while (len) {
-               *dst++ = (u16)(*src++);
-               len--;
-       }
-}
-
-static void rspi_memory_from_8bit(void *buf, const void *data, unsigned len)
-{
-       u8 *dst = buf;
-       const u16 *src = data;
-
-       while (len) {
-               *dst++ = (u8)*src++;
-               len--;
-       }
-}
+       struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL;
+       u8 irq_mask = 0;
+       unsigned int other_irq = 0;
+       dma_cookie_t cookie;
+       int ret;
 
-static int rspi_send_dma(struct rspi_data *rspi, struct spi_transfer *t)
-{
-       struct scatterlist sg;
-       const void *buf = NULL;
-       struct dma_async_tx_descriptor *desc;
-       unsigned int len;
-       int ret = 0;
-
-       if (rspi->dma_width_16bit) {
-               void *tmp;
-               /*
-                * If DMAC bus width is 16-bit, the driver allocates a dummy
-                * buffer. And, the driver converts original data into the
-                * DMAC data as the following format:
-                *  original data: 1st byte, 2nd byte ...
-                *  DMAC data:     1st byte, dummy, 2nd byte, dummy ...
-                */
-               len = t->len * 2;
-               tmp = kmalloc(len, GFP_KERNEL);
-               if (!tmp)
-                       return -ENOMEM;
-               rspi_memory_to_8bit(tmp, t->tx_buf, t->len);
-               buf = tmp;
-       } else {
-               len = t->len;
-               buf = t->tx_buf;
-       }
+       if (tx) {
+               desc_tx = dmaengine_prep_slave_sg(rspi->master->dma_tx,
+                                       tx->sgl, tx->nents, DMA_TO_DEVICE,
+                                       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+               if (!desc_tx)
+                       return -EIO;
 
-       if (!rspi_dma_map_sg(&sg, buf, len, rspi->chan_tx, DMA_TO_DEVICE)) {
-               ret = -EFAULT;
-               goto end_nomap;
+               irq_mask |= SPCR_SPTIE;
        }
-       desc = dmaengine_prep_slave_sg(rspi->chan_tx, &sg, 1, DMA_TO_DEVICE,
-                                      DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
-       if (!desc) {
-               ret = -EIO;
-               goto end;
+       if (rx) {
+               desc_rx = dmaengine_prep_slave_sg(rspi->master->dma_rx,
+                                       rx->sgl, rx->nents, DMA_FROM_DEVICE,
+                                       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+               if (!desc_rx)
+                       return -EIO;
+
+               irq_mask |= SPCR_SPRIE;
        }
 
        /*
-        * DMAC needs SPTIE, but if SPTIE is set, this IRQ routine will be
+        * DMAC needs SPxIE, but if SPxIE is set, the IRQ routine will be
         * called. So, this driver disables the IRQ while DMA transfer.
         */
-       disable_irq(rspi->tx_irq);
+       if (tx)
+               disable_irq(other_irq = rspi->tx_irq);
+       if (rx && rspi->rx_irq != other_irq)
+               disable_irq(rspi->rx_irq);
 
-       rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_TXMD, RSPI_SPCR);
-       rspi_enable_irq(rspi, SPCR_SPTIE);
+       rspi_enable_irq(rspi, irq_mask);
        rspi->dma_callbacked = 0;
 
-       desc->callback = rspi_dma_complete;
-       desc->callback_param = rspi;
-       dmaengine_submit(desc);
-       dma_async_issue_pending(rspi->chan_tx);
+       if (rx) {
+               desc_rx->callback = rspi_dma_complete;
+               desc_rx->callback_param = rspi;
+               cookie = dmaengine_submit(desc_rx);
+               if (dma_submit_error(cookie))
+                       return cookie;
+               dma_async_issue_pending(rspi->master->dma_rx);
+       }
+       if (tx) {
+               if (rx) {
+                       /* No callback */
+                       desc_tx->callback = NULL;
+               } else {
+                       desc_tx->callback = rspi_dma_complete;
+                       desc_tx->callback_param = rspi;
+               }
+               cookie = dmaengine_submit(desc_tx);
+               if (dma_submit_error(cookie))
+                       return cookie;
+               dma_async_issue_pending(rspi->master->dma_tx);
+       }
 
        ret = wait_event_interruptible_timeout(rspi->wait,
                                               rspi->dma_callbacked, HZ);
@@ -542,15 +531,13 @@ static int rspi_send_dma(struct rspi_data *rspi, struct spi_transfer *t)
                ret = 0;
        else if (!ret)
                ret = -ETIMEDOUT;
-       rspi_disable_irq(rspi, SPCR_SPTIE);
 
-       enable_irq(rspi->tx_irq);
+       rspi_disable_irq(rspi, irq_mask);
 
-end:
-       rspi_dma_unmap_sg(&sg, rspi->chan_tx, DMA_TO_DEVICE);
-end_nomap:
-       if (rspi->dma_width_16bit)
-               kfree(buf);
+       if (tx)
+               enable_irq(rspi->tx_irq);
+       if (rx && rspi->rx_irq != other_irq)
+               enable_irq(rspi->rx_irq);
 
        return ret;
 }
@@ -585,157 +572,37 @@ static void qspi_receive_init(const struct rspi_data *rspi)
        rspi_write8(rspi, 0, QSPI_SPBFCR);
 }
 
-static int rspi_receive_dma(struct rspi_data *rspi, struct spi_transfer *t)
+static bool __rspi_can_dma(const struct rspi_data *rspi,
+                          const struct spi_transfer *xfer)
 {
-       struct scatterlist sg, sg_dummy;
-       void *dummy = NULL, *rx_buf = NULL;
-       struct dma_async_tx_descriptor *desc, *desc_dummy;
-       unsigned int len;
-       int ret = 0;
-
-       if (rspi->dma_width_16bit) {
-               /*
-                * If DMAC bus width is 16-bit, the driver allocates a dummy
-                * buffer. And, finally the driver converts the DMAC data into
-                * actual data as the following format:
-                *  DMAC data:   1st byte, dummy, 2nd byte, dummy ...
-                *  actual data: 1st byte, 2nd byte ...
-                */
-               len = t->len * 2;
-               rx_buf = kmalloc(len, GFP_KERNEL);
-               if (!rx_buf)
-                       return -ENOMEM;
-        } else {
-               len = t->len;
-               rx_buf = t->rx_buf;
-       }
-
-       /* prepare dummy transfer to generate SPI clocks */
-       dummy = kzalloc(len, GFP_KERNEL);
-       if (!dummy) {
-               ret = -ENOMEM;
-               goto end_nomap;
-       }
-       if (!rspi_dma_map_sg(&sg_dummy, dummy, len, rspi->chan_tx,
-                            DMA_TO_DEVICE)) {
-               ret = -EFAULT;
-               goto end_nomap;
-       }
-       desc_dummy = dmaengine_prep_slave_sg(rspi->chan_tx, &sg_dummy, 1,
-                       DMA_TO_DEVICE, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
-       if (!desc_dummy) {
-               ret = -EIO;
-               goto end_dummy_mapped;
-       }
-
-       /* prepare receive transfer */
-       if (!rspi_dma_map_sg(&sg, rx_buf, len, rspi->chan_rx,
-                            DMA_FROM_DEVICE)) {
-               ret = -EFAULT;
-               goto end_dummy_mapped;
-
-       }
-       desc = dmaengine_prep_slave_sg(rspi->chan_rx, &sg, 1, DMA_FROM_DEVICE,
-                                      DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
-       if (!desc) {
-               ret = -EIO;
-               goto end;
-       }
-
-       rspi_receive_init(rspi);
-
-       /*
-        * DMAC needs SPTIE, but if SPTIE is set, this IRQ routine will be
-        * called. So, this driver disables the IRQ while DMA transfer.
-        */
-       disable_irq(rspi->tx_irq);
-       if (rspi->rx_irq != rspi->tx_irq)
-               disable_irq(rspi->rx_irq);
-
-       rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_TXMD, RSPI_SPCR);
-       rspi_enable_irq(rspi, SPCR_SPTIE | SPCR_SPRIE);
-       rspi->dma_callbacked = 0;
-
-       desc->callback = rspi_dma_complete;
-       desc->callback_param = rspi;
-       dmaengine_submit(desc);
-       dma_async_issue_pending(rspi->chan_rx);
-
-       desc_dummy->callback = NULL;    /* No callback */
-       dmaengine_submit(desc_dummy);
-       dma_async_issue_pending(rspi->chan_tx);
-
-       ret = wait_event_interruptible_timeout(rspi->wait,
-                                              rspi->dma_callbacked, HZ);
-       if (ret > 0 && rspi->dma_callbacked)
-               ret = 0;
-       else if (!ret)
-               ret = -ETIMEDOUT;
-       rspi_disable_irq(rspi, SPCR_SPTIE | SPCR_SPRIE);
-
-       enable_irq(rspi->tx_irq);
-       if (rspi->rx_irq != rspi->tx_irq)
-               enable_irq(rspi->rx_irq);
-
-end:
-       rspi_dma_unmap_sg(&sg, rspi->chan_rx, DMA_FROM_DEVICE);
-end_dummy_mapped:
-       rspi_dma_unmap_sg(&sg_dummy, rspi->chan_tx, DMA_TO_DEVICE);
-end_nomap:
-       if (rspi->dma_width_16bit) {
-               if (!ret)
-                       rspi_memory_from_8bit(t->rx_buf, rx_buf, t->len);
-               kfree(rx_buf);
-       }
-       kfree(dummy);
-
-       return ret;
+       return xfer->len > rspi->ops->fifo_size;
 }
 
-static int rspi_is_dma(const struct rspi_data *rspi, struct spi_transfer *t)
+static bool rspi_can_dma(struct spi_master *master, struct spi_device *spi,
+                        struct spi_transfer *xfer)
 {
-       if (t->tx_buf && rspi->chan_tx)
-               return 1;
-       /* If the module receives data by DMAC, it also needs TX DMAC */
-       if (t->rx_buf && rspi->chan_tx && rspi->chan_rx)
-               return 1;
+       struct rspi_data *rspi = spi_master_get_devdata(master);
 
-       return 0;
+       return __rspi_can_dma(rspi, xfer);
 }
 
-static int rspi_transfer_out_in(struct rspi_data *rspi,
+static int rspi_common_transfer(struct rspi_data *rspi,
                                struct spi_transfer *xfer)
 {
-       int remain = xfer->len, ret;
-       const u8 *tx_buf = xfer->tx_buf;
-       u8 *rx_buf = xfer->rx_buf;
-       u8 spcr, data;
-
-       rspi_receive_init(rspi);
-
-       spcr = rspi_read8(rspi, RSPI_SPCR);
-       if (rx_buf)
-               spcr &= ~SPCR_TXMD;
-       else
-               spcr |= SPCR_TXMD;
-       rspi_write8(rspi, spcr, RSPI_SPCR);
+       int ret;
 
-       while (remain > 0) {
-               data = tx_buf ? *tx_buf++ : DUMMY_DATA;
-               ret = rspi_data_out(rspi, data);
-               if (ret < 0)
-                       return ret;
-               if (rx_buf) {
-                       ret = rspi_data_in(rspi);
-                       if (ret < 0)
-                               return ret;
-                       *rx_buf++ = ret;
-               }
-               remain--;
+       if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) {
+               /* rx_buf can be NULL on RSPI on SH in TX-only Mode */
+               return rspi_dma_transfer(rspi, &xfer->tx_sg,
+                                        xfer->rx_buf ? &xfer->rx_sg : NULL);
        }
 
+       ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len);
+       if (ret < 0)
+               return ret;
+
        /* Wait for the last transmission */
-       rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
+       rspi_wait_for_tx_empty(rspi);
 
        return 0;
 }
@@ -744,46 +611,18 @@ static int rspi_transfer_one(struct spi_master *master, struct spi_device *spi,
                             struct spi_transfer *xfer)
 {
        struct rspi_data *rspi = spi_master_get_devdata(master);
-       int ret;
+       u8 spcr;
 
-       if (!rspi_is_dma(rspi, xfer))
-               return rspi_transfer_out_in(rspi, xfer);
-
-       if (xfer->tx_buf) {
-               ret = rspi_send_dma(rspi, xfer);
-               if (ret < 0)
-                       return ret;
-       }
-       if (xfer->rx_buf)
-               return rspi_receive_dma(rspi, xfer);
-
-       return 0;
-}
-
-static int rspi_rz_transfer_out_in(struct rspi_data *rspi,
-                                  struct spi_transfer *xfer)
-{
-       int remain = xfer->len, ret;
-       const u8 *tx_buf = xfer->tx_buf;
-       u8 *rx_buf = xfer->rx_buf;
-       u8 data;
-
-       rspi_rz_receive_init(rspi);
-
-       while (remain > 0) {
-               data = tx_buf ? *tx_buf++ : DUMMY_DATA;
-               ret = rspi_data_out_in(rspi, data);
-               if (ret < 0)
-                       return ret;
-               if (rx_buf)
-                       *rx_buf++ = ret;
-               remain--;
+       spcr = rspi_read8(rspi, RSPI_SPCR);
+       if (xfer->rx_buf) {
+               rspi_receive_init(rspi);
+               spcr &= ~SPCR_TXMD;
+       } else {
+               spcr |= SPCR_TXMD;
        }
+       rspi_write8(rspi, spcr, RSPI_SPCR);
 
-       /* Wait for the last transmission */
-       rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
-
-       return 0;
+       return rspi_common_transfer(rspi, xfer);
 }
 
 static int rspi_rz_transfer_one(struct spi_master *master,
@@ -791,68 +630,44 @@ static int rspi_rz_transfer_one(struct spi_master *master,
                                struct spi_transfer *xfer)
 {
        struct rspi_data *rspi = spi_master_get_devdata(master);
+       int ret;
 
-       return rspi_rz_transfer_out_in(rspi, xfer);
+       rspi_rz_receive_init(rspi);
+
+       return rspi_common_transfer(rspi, xfer);
 }
 
 static int qspi_transfer_out_in(struct rspi_data *rspi,
                                struct spi_transfer *xfer)
 {
-       int remain = xfer->len, ret;
-       const u8 *tx_buf = xfer->tx_buf;
-       u8 *rx_buf = xfer->rx_buf;
-       u8 data;
-
        qspi_receive_init(rspi);
 
-       while (remain > 0) {
-               data = tx_buf ? *tx_buf++ : DUMMY_DATA;
-               ret = rspi_data_out_in(rspi, data);
-               if (ret < 0)
-                       return ret;
-               if (rx_buf)
-                       *rx_buf++ = ret;
-               remain--;
-       }
-
-       /* Wait for the last transmission */
-       rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
-
-       return 0;
+       return rspi_common_transfer(rspi, xfer);
 }
 
 static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer)
 {
-       const u8 *buf = xfer->tx_buf;
-       unsigned int i;
        int ret;
 
-       for (i = 0; i < xfer->len; i++) {
-               ret = rspi_data_out(rspi, *buf++);
-               if (ret < 0)
-                       return ret;
-       }
+       if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer))
+               return rspi_dma_transfer(rspi, &xfer->tx_sg, NULL);
+
+       ret = rspi_pio_transfer(rspi, xfer->tx_buf, NULL, xfer->len);
+       if (ret < 0)
+               return ret;
 
        /* Wait for the last transmission */
-       rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
+       rspi_wait_for_tx_empty(rspi);
 
        return 0;
 }
 
 static int qspi_transfer_in(struct rspi_data *rspi, struct spi_transfer *xfer)
 {
-       u8 *buf = xfer->rx_buf;
-       unsigned int i;
-       int ret;
-
-       for (i = 0; i < xfer->len; i++) {
-               ret = rspi_data_in(rspi);
-               if (ret < 0)
-                       return ret;
-               *buf++ = ret;
-       }
+       if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer))
+               return rspi_dma_transfer(rspi, NULL, &xfer->rx_sg);
 
-       return 0;
+       return rspi_pio_transfer(rspi, NULL, xfer->rx_buf, xfer->len);
 }
 
 static int qspi_transfer_one(struct spi_master *master, struct spi_device *spi,
@@ -862,10 +677,10 @@ static int qspi_transfer_one(struct spi_master *master, struct spi_device *spi,
 
        if (spi->mode & SPI_LOOP) {
                return qspi_transfer_out_in(rspi, xfer);
-       } else if (xfer->tx_buf && xfer->tx_nbits > SPI_NBITS_SINGLE) {
+       } else if (xfer->tx_nbits > SPI_NBITS_SINGLE) {
                /* Quad or Dual SPI Write */
                return qspi_transfer_out(rspi, xfer);
-       } else if (xfer->rx_buf && xfer->rx_nbits > SPI_NBITS_SINGLE) {
+       } else if (xfer->rx_nbits > SPI_NBITS_SINGLE) {
                /* Quad or Dual SPI Read */
                return qspi_transfer_in(rspi, xfer);
        } else {
@@ -1046,65 +861,78 @@ static irqreturn_t rspi_irq_tx(int irq, void *_sr)
        return 0;
 }
 
-static int rspi_request_dma(struct rspi_data *rspi,
-                                     struct platform_device *pdev)
+static struct dma_chan *rspi_request_dma_chan(struct device *dev,
+                                             enum dma_transfer_direction dir,
+                                             unsigned int id,
+                                             dma_addr_t port_addr)
 {
-       const struct rspi_plat_data *rspi_pd = dev_get_platdata(&pdev->dev);
-       struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        dma_cap_mask_t mask;
+       struct dma_chan *chan;
        struct dma_slave_config cfg;
        int ret;
 
-       if (!res || !rspi_pd)
-               return 0;       /* The driver assumes no error. */
+       dma_cap_zero(mask);
+       dma_cap_set(DMA_SLAVE, mask);
 
-       rspi->dma_width_16bit = rspi_pd->dma_width_16bit;
-
-       /* If the module receives data by DMAC, it also needs TX DMAC */
-       if (rspi_pd->dma_rx_id && rspi_pd->dma_tx_id) {
-               dma_cap_zero(mask);
-               dma_cap_set(DMA_SLAVE, mask);
-               rspi->chan_rx = dma_request_channel(mask, shdma_chan_filter,
-                                                   (void *)rspi_pd->dma_rx_id);
-               if (rspi->chan_rx) {
-                       cfg.slave_id = rspi_pd->dma_rx_id;
-                       cfg.direction = DMA_DEV_TO_MEM;
-                       cfg.dst_addr = 0;
-                       cfg.src_addr = res->start + RSPI_SPDR;
-                       ret = dmaengine_slave_config(rspi->chan_rx, &cfg);
-                       if (!ret)
-                               dev_info(&pdev->dev, "Use DMA when rx.\n");
-                       else
-                               return ret;
-               }
+       chan = dma_request_channel(mask, shdma_chan_filter,
+                                  (void *)(unsigned long)id);
+       if (!chan) {
+               dev_warn(dev, "dma_request_channel failed\n");
+               return NULL;
        }
-       if (rspi_pd->dma_tx_id) {
-               dma_cap_zero(mask);
-               dma_cap_set(DMA_SLAVE, mask);
-               rspi->chan_tx = dma_request_channel(mask, shdma_chan_filter,
-                                                   (void *)rspi_pd->dma_tx_id);
-               if (rspi->chan_tx) {
-                       cfg.slave_id = rspi_pd->dma_tx_id;
-                       cfg.direction = DMA_MEM_TO_DEV;
-                       cfg.dst_addr = res->start + RSPI_SPDR;
-                       cfg.src_addr = 0;
-                       ret = dmaengine_slave_config(rspi->chan_tx, &cfg);
-                       if (!ret)
-                               dev_info(&pdev->dev, "Use DMA when tx\n");
-                       else
-                               return ret;
-               }
+
+       memset(&cfg, 0, sizeof(cfg));
+       cfg.slave_id = id;
+       cfg.direction = dir;
+       if (dir == DMA_MEM_TO_DEV)
+               cfg.dst_addr = port_addr;
+       else
+               cfg.src_addr = port_addr;
+
+       ret = dmaengine_slave_config(chan, &cfg);
+       if (ret) {
+               dev_warn(dev, "dmaengine_slave_config failed %d\n", ret);
+               dma_release_channel(chan);
+               return NULL;
        }
 
+       return chan;
+}
+
+static int rspi_request_dma(struct device *dev, struct spi_master *master,
+                           const struct resource *res)
+{
+       const struct rspi_plat_data *rspi_pd = dev_get_platdata(dev);
+
+       if (!rspi_pd || !rspi_pd->dma_rx_id || !rspi_pd->dma_tx_id)
+               return 0;       /* The driver assumes no error. */
+
+       master->dma_rx = rspi_request_dma_chan(dev, DMA_DEV_TO_MEM,
+                                              rspi_pd->dma_rx_id,
+                                              res->start + RSPI_SPDR);
+       if (!master->dma_rx)
+               return -ENODEV;
+
+       master->dma_tx = rspi_request_dma_chan(dev, DMA_MEM_TO_DEV,
+                                              rspi_pd->dma_tx_id,
+                                              res->start + RSPI_SPDR);
+       if (!master->dma_tx) {
+               dma_release_channel(master->dma_rx);
+               master->dma_rx = NULL;
+               return -ENODEV;
+       }
+
+       master->can_dma = rspi_can_dma;
+       dev_info(dev, "DMA available");
        return 0;
 }
 
 static void rspi_release_dma(struct rspi_data *rspi)
 {
-       if (rspi->chan_tx)
-               dma_release_channel(rspi->chan_tx);
-       if (rspi->chan_rx)
-               dma_release_channel(rspi->chan_rx);
+       if (rspi->master->dma_tx)
+               dma_release_channel(rspi->master->dma_tx);
+       if (rspi->master->dma_rx)
+               dma_release_channel(rspi->master->dma_rx);
 }
 
 static int rspi_remove(struct platform_device *pdev)
@@ -1118,23 +946,29 @@ static int rspi_remove(struct platform_device *pdev)
 }
 
 static const struct spi_ops rspi_ops = {
-       .set_config_register =          rspi_set_config_register,
-       .transfer_one =                 rspi_transfer_one,
-       .mode_bits =                    SPI_CPHA | SPI_CPOL | SPI_LOOP,
+       .set_config_register =  rspi_set_config_register,
+       .transfer_one =         rspi_transfer_one,
+       .mode_bits =            SPI_CPHA | SPI_CPOL | SPI_LOOP,
+       .flags =                SPI_MASTER_MUST_TX,
+       .fifo_size =            8,
 };
 
 static const struct spi_ops rspi_rz_ops = {
-       .set_config_register =          rspi_rz_set_config_register,
-       .transfer_one =                 rspi_rz_transfer_one,
-       .mode_bits =                    SPI_CPHA | SPI_CPOL | SPI_LOOP,
+       .set_config_register =  rspi_rz_set_config_register,
+       .transfer_one =         rspi_rz_transfer_one,
+       .mode_bits =            SPI_CPHA | SPI_CPOL | SPI_LOOP,
+       .flags =                SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX,
+       .fifo_size =            8,      /* 8 for TX, 32 for RX */
 };
 
 static const struct spi_ops qspi_ops = {
-       .set_config_register =          qspi_set_config_register,
-       .transfer_one =                 qspi_transfer_one,
-       .mode_bits =                    SPI_CPHA | SPI_CPOL | SPI_LOOP |
-                                       SPI_TX_DUAL | SPI_TX_QUAD |
-                                       SPI_RX_DUAL | SPI_RX_QUAD,
+       .set_config_register =  qspi_set_config_register,
+       .transfer_one =         qspi_transfer_one,
+       .mode_bits =            SPI_CPHA | SPI_CPOL | SPI_LOOP |
+                               SPI_TX_DUAL | SPI_TX_QUAD |
+                               SPI_RX_DUAL | SPI_RX_QUAD,
+       .flags =                SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX,
+       .fifo_size =            32,
 };
 
 #ifdef CONFIG_OF
@@ -1254,6 +1088,7 @@ static int rspi_probe(struct platform_device *pdev)
        master->prepare_message = rspi_prepare_message;
        master->unprepare_message = rspi_unprepare_message;
        master->mode_bits = ops->mode_bits;
+       master->flags = ops->flags;
        master->dev.of_node = pdev->dev.of_node;
 
        ret = platform_get_irq_byname(pdev, "rx");
@@ -1291,11 +1126,9 @@ static int rspi_probe(struct platform_device *pdev)
                goto error2;
        }
 
-       ret = rspi_request_dma(rspi, pdev);
-       if (ret < 0) {
-               dev_err(&pdev->dev, "rspi_request_dma failed.\n");
-               goto error3;
-       }
+       ret = rspi_request_dma(&pdev->dev, master, res);
+       if (ret < 0)
+               dev_warn(&pdev->dev, "DMA not available, using PIO\n");
 
        ret = devm_spi_register_master(&pdev->dev, master);
        if (ret < 0) {