Hi Anton, Sascha, On 24.02.2016 10:20, Sascha Hauer wrote: > From: Anton Bondarenko <anton.bondarenko.sama@xxxxxxxxx> > > DMA transfer for SPI was limited to up to 8 bits word size until now. > Sync in SPI burst size and DMA bus width is necessary to correctly > support 16 and 32 BPW. > > Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@xxxxxxxxx> > Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> > --- > drivers/spi/spi-imx.c | 118 ++++++++++++++++++++++++++++++++++++++------------ > 1 file changed, 91 insertions(+), 27 deletions(-) > > diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c > index 567a242..15b23f0 100644 > --- a/drivers/spi/spi-imx.c > +++ b/drivers/spi/spi-imx.c > @@ -89,11 +89,15 @@ struct spi_imx_data { > > struct completion xfer_done; > void __iomem *base; > + unsigned long base_phys; > + > struct clk *clk_per; > struct clk *clk_ipg; > unsigned long spi_clk; > unsigned int spi_bus_clk; > > + unsigned int bytes_per_word; > + > unsigned int count; > void (*tx)(struct spi_imx_data *); > void (*rx)(struct spi_imx_data *); > @@ -199,15 +203,35 @@ static unsigned int spi_imx_clkdiv_2(unsigned int fin, > return 7; > } > > +static int spi_imx_bytes_per_word(const int bpw) > +{ > + return DIV_ROUND_UP(bpw, BITS_PER_BYTE); > +} > + > static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi, > struct spi_transfer *transfer) > { > struct spi_imx_data *spi_imx = spi_master_get_devdata(master); > + unsigned int bpw = transfer->bits_per_word; > + > + if (!master->dma_rx) > + return false; > + > + if (!bpw) > + bpw = spi->bits_per_word; > + > + bpw = spi_imx_bytes_per_word(bpw); > + > + if (bpw != 1 && bpw != 2 && bpw != 4) > + return false; > + > + if (transfer->len < spi_imx->wml * bpw) > + return false; > + > + if (transfer->len % (spi_imx->wml * bpw)) > + return false; > > - if (master->dma_rx && transfer->len >= spi_imx->wml && > - (transfer->len % spi_imx->wml) == 0) > - return true; > - return false; > + return true; > } > > #define MX51_ECSPI_CTRL 0x08 > @@ -775,11 +799,63 @@ static irqreturn_t spi_imx_isr(int irq, void *dev_id) > return IRQ_HANDLED; > } > > +static int spi_imx_dma_configure(struct spi_master *master, > + int bytes_per_word) > +{ > + int ret; > + enum dma_slave_buswidth buswidth; > + struct dma_slave_config rx = {}, tx = {}; > + struct spi_imx_data *spi_imx = spi_master_get_devdata(master); > + > + if (bytes_per_word == spi_imx->bytes_per_word) > + /* Same as last time */ > + return 0; > + > + switch (bytes_per_word) { > + case 4: > + buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES; > + break; > + case 2: > + buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES; > + break; > + case 1: > + buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE; > + break; > + default: > + return -EINVAL; > + } > + > + tx.direction = DMA_MEM_TO_DEV; > + tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA; > + tx.dst_addr_width = buswidth; > + tx.dst_maxburst = spi_imx->wml; > + ret = dmaengine_slave_config(master->dma_tx, &tx); > + if (ret) { > + dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret); > + return ret; > + } > + > + rx.direction = DMA_DEV_TO_MEM; > + rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA; > + rx.src_addr_width = buswidth; > + rx.src_maxburst = spi_imx->wml; > + ret = dmaengine_slave_config(master->dma_rx, &rx); > + if (ret) { > + dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret); > + return ret; > + } > + > + spi_imx->bytes_per_word = bytes_per_word; > + > + return 0; > +} > + > static int spi_imx_setupxfer(struct spi_device *spi, > struct spi_transfer *t) > { > struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); > struct spi_imx_config config; > + int ret; > > config.bpw = t ? t->bits_per_word : spi->bits_per_word; > config.speed_hz = t ? t->speed_hz : spi->max_speed_hz; > @@ -808,6 +884,13 @@ static int spi_imx_setupxfer(struct spi_device *spi, > else > spi_imx->usedma = 0; > > + if (spi_imx->usedma) { > + ret = spi_imx_dma_configure(spi->master, > + spi_imx_bytes_per_word(config.bpw)); > + if (ret) > + return ret; > + } > + > spi_imx->devtype_data->config(spi_imx, &config); > > return 0; > @@ -829,10 +912,8 @@ static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx) > } > > static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx, > - struct spi_master *master, > - const struct resource *res) > + struct spi_master *master) > { > - struct dma_slave_config slave_config = {}; > int ret; > > /* use pio mode for i.mx6dl chip TKT238285 */ > @@ -850,16 +931,6 @@ static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx, > goto err; > } > > - slave_config.direction = DMA_MEM_TO_DEV; > - slave_config.dst_addr = res->start + MXC_CSPITXDATA; > - slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; > - slave_config.dst_maxburst = spi_imx->wml; > - ret = dmaengine_slave_config(master->dma_tx, &slave_config); > - if (ret) { > - dev_err(dev, "error in TX dma configuration.\n"); > - goto err; > - } > - > /* Prepare for RX : */ > master->dma_rx = dma_request_slave_channel_reason(dev, "rx"); > if (IS_ERR(master->dma_rx)) { > @@ -869,15 +940,7 @@ static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx, > goto err; > } > > - slave_config.direction = DMA_DEV_TO_MEM; > - slave_config.src_addr = res->start + MXC_CSPIRXDATA; > - slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; > - slave_config.src_maxburst = spi_imx->wml; > - ret = dmaengine_slave_config(master->dma_rx, &slave_config); > - if (ret) { > - dev_err(dev, "error in RX dma configuration.\n"); > - goto err; > - } > + spi_imx_dma_configure(master, 1); here it might make sense to check for returned error code. > > init_completion(&spi_imx->dma_rx_completion); > init_completion(&spi_imx->dma_tx_completion); > @@ -1164,6 +1227,7 @@ static int spi_imx_probe(struct platform_device *pdev) > ret = PTR_ERR(spi_imx->base); > goto out_master_put; > } > + spi_imx->base_phys = res->start; > > irq = platform_get_irq(pdev, 0); > if (irq < 0) { > @@ -1204,7 +1268,7 @@ static int spi_imx_probe(struct platform_device *pdev) > * other chips. > */ > if (is_imx51_ecspi(spi_imx)) { > - ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master, res); > + ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master); > if (ret == -EPROBE_DEFER) > goto out_clk_put; > > -- With best wishes, Vladimir -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html