diff options
| -rw-r--r-- | drivers/spi/spi-imx.c | 118 |
1 files changed, 91 insertions, 27 deletions
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index 567a2426e314..15b23f0b83e8 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); 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; |