diff options
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/spi/spi-omap2-mcspi.c | 256 |
1 files changed, 144 insertions, 112 deletions
diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c index 164c15d6a1bb..5560b708e628 100644 --- a/drivers/spi/spi-omap2-mcspi.c +++ b/drivers/spi/spi-omap2-mcspi.c @@ -315,49 +315,27 @@ static void omap2_mcspi_tx_callback(void *data) omap2_mcspi_set_dma_req(spi, 0, 0); } -static unsigned -omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) +static void omap2_mcspi_tx_dma(struct spi_device *spi, + struct spi_transfer *xfer, + struct dma_slave_config cfg) { struct omap2_mcspi *mcspi; - struct omap2_mcspi_cs *cs = spi->controller_state; struct omap2_mcspi_dma *mcspi_dma; unsigned int count; - int word_len, element_count; - int elements = 0; - u32 l; u8 * rx; const u8 * tx; void __iomem *chstat_reg; - struct dma_slave_config cfg; - enum dma_slave_buswidth width; - unsigned es; + struct omap2_mcspi_cs *cs = spi->controller_state; mcspi = spi_master_get_devdata(spi->master); mcspi_dma = &mcspi->dma_channels[spi->chip_select]; - l = mcspi_cached_chconf0(spi); + count = xfer->len; + rx = xfer->rx_buf; + tx = xfer->tx_buf; chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0; - if (cs->word_len <= 8) { - width = DMA_SLAVE_BUSWIDTH_1_BYTE; - es = 1; - } else if (cs->word_len <= 16) { - width = DMA_SLAVE_BUSWIDTH_2_BYTES; - es = 2; - } else { - width = DMA_SLAVE_BUSWIDTH_4_BYTES; - es = 4; - } - - memset(&cfg, 0, sizeof(cfg)); - cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0; - cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0; - cfg.src_addr_width = width; - cfg.dst_addr_width = width; - cfg.src_maxburst = 1; - cfg.dst_maxburst = 1; - - if (xfer->tx_buf && mcspi_dma->dma_tx) { + if (mcspi_dma->dma_tx) { struct dma_async_tx_descriptor *tx; struct scatterlist sg; @@ -368,7 +346,7 @@ omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) sg_dma_len(&sg) = xfer->len; tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, &sg, 1, - DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (tx) { tx->callback = omap2_mcspi_tx_callback; tx->callback_param = spi; @@ -377,8 +355,50 @@ omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) /* FIXME: fall back to PIO? */ } } + dma_async_issue_pending(mcspi_dma->dma_tx); + omap2_mcspi_set_dma_req(spi, 0, 1); - if (xfer->rx_buf && mcspi_dma->dma_rx) { + wait_for_completion(&mcspi_dma->dma_tx_completion); + dma_unmap_single(mcspi->dev, xfer->tx_dma, count, + DMA_TO_DEVICE); + + /* for TX_ONLY mode, be sure all words have shifted out */ + if (rx == NULL) { + if (mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_TXS) < 0) + dev_err(&spi->dev, "TXS timed out\n"); + else if (mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_EOT) < 0) + dev_err(&spi->dev, "EOT timed out\n"); + } +} + +static unsigned +omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer, + struct dma_slave_config cfg, + unsigned es) +{ + struct omap2_mcspi *mcspi; + struct omap2_mcspi_dma *mcspi_dma; + unsigned int count; + u32 l; + int elements = 0; + int word_len, element_count; + struct omap2_mcspi_cs *cs = spi->controller_state; + mcspi = spi_master_get_devdata(spi->master); + mcspi_dma = &mcspi->dma_channels[spi->chip_select]; + count = xfer->len; + word_len = cs->word_len; + l = mcspi_cached_chconf0(spi); + + if (word_len <= 8) + element_count = count; + else if (word_len <= 16) + element_count = count >> 1; + else /* word_len <= 32 */ + element_count = count >> 2; + + if (mcspi_dma->dma_rx) { struct dma_async_tx_descriptor *tx; struct scatterlist sg; size_t len = xfer->len - es; @@ -393,108 +413,120 @@ omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) sg_dma_len(&sg) = len; tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, &sg, 1, - DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | + DMA_CTRL_ACK); if (tx) { tx->callback = omap2_mcspi_rx_callback; tx->callback_param = spi; dmaengine_submit(tx); } else { - /* FIXME: fall back to PIO? */ - } - } - - count = xfer->len; - word_len = cs->word_len; - - rx = xfer->rx_buf; - tx = xfer->tx_buf; - - if (word_len <= 8) { - element_count = count; - } else if (word_len <= 16) { - element_count = count >> 1; - } else /* word_len <= 32 */ { - element_count = count >> 2; - } - - if (tx != NULL) { - dma_async_issue_pending(mcspi_dma->dma_tx); - omap2_mcspi_set_dma_req(spi, 0, 1); - } - - if (rx != NULL) { - dma_async_issue_pending(mcspi_dma->dma_rx); - omap2_mcspi_set_dma_req(spi, 1, 1); - } - - if (tx != NULL) { - wait_for_completion(&mcspi_dma->dma_tx_completion); - dma_unmap_single(mcspi->dev, xfer->tx_dma, count, - DMA_TO_DEVICE); - - /* for TX_ONLY mode, be sure all words have shifted out */ - if (rx == NULL) { - if (mcspi_wait_for_reg_bit(chstat_reg, - OMAP2_MCSPI_CHSTAT_TXS) < 0) - dev_err(&spi->dev, "TXS timed out\n"); - else if (mcspi_wait_for_reg_bit(chstat_reg, - OMAP2_MCSPI_CHSTAT_EOT) < 0) - dev_err(&spi->dev, "EOT timed out\n"); + /* FIXME: fall back to PIO? */ } } - if (rx != NULL) { - wait_for_completion(&mcspi_dma->dma_rx_completion); - dma_unmap_single(mcspi->dev, xfer->rx_dma, count, - DMA_FROM_DEVICE); - omap2_mcspi_set_enable(spi, 0); + dma_async_issue_pending(mcspi_dma->dma_rx); + omap2_mcspi_set_dma_req(spi, 1, 1); - elements = element_count - 1; + wait_for_completion(&mcspi_dma->dma_rx_completion); + dma_unmap_single(mcspi->dev, xfer->rx_dma, count, + DMA_FROM_DEVICE); + omap2_mcspi_set_enable(spi, 0); - if (l & OMAP2_MCSPI_CHCONF_TURBO) { - elements--; + elements = element_count - 1; - if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0) - & OMAP2_MCSPI_CHSTAT_RXS)) { - u32 w; - - w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0); - if (word_len <= 8) - ((u8 *)xfer->rx_buf)[elements++] = w; - else if (word_len <= 16) - ((u16 *)xfer->rx_buf)[elements++] = w; - else /* word_len <= 32 */ - ((u32 *)xfer->rx_buf)[elements++] = w; - } else { - dev_err(&spi->dev, - "DMA RX penultimate word empty"); - count -= (word_len <= 8) ? 2 : - (word_len <= 16) ? 4 : - /* word_len <= 32 */ 8; - omap2_mcspi_set_enable(spi, 1); - return count; - } - } + if (l & OMAP2_MCSPI_CHCONF_TURBO) { + elements--; if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0) - & OMAP2_MCSPI_CHSTAT_RXS)) { + & OMAP2_MCSPI_CHSTAT_RXS)) { u32 w; w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0); if (word_len <= 8) - ((u8 *)xfer->rx_buf)[elements] = w; + ((u8 *)xfer->rx_buf)[elements++] = w; else if (word_len <= 16) - ((u16 *)xfer->rx_buf)[elements] = w; + ((u16 *)xfer->rx_buf)[elements++] = w; else /* word_len <= 32 */ - ((u32 *)xfer->rx_buf)[elements] = w; + ((u32 *)xfer->rx_buf)[elements++] = w; } else { - dev_err(&spi->dev, "DMA RX last word empty"); - count -= (word_len <= 8) ? 1 : - (word_len <= 16) ? 2 : - /* word_len <= 32 */ 4; + dev_err(&spi->dev, "DMA RX penultimate word empty"); + count -= (word_len <= 8) ? 2 : + (word_len <= 16) ? 4 : + /* word_len <= 32 */ 8; + omap2_mcspi_set_enable(spi, 1); + return count; } - omap2_mcspi_set_enable(spi, 1); } + if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0) + & OMAP2_MCSPI_CHSTAT_RXS)) { + u32 w; + + w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0); + if (word_len <= 8) + ((u8 *)xfer->rx_buf)[elements] = w; + else if (word_len <= 16) + ((u16 *)xfer->rx_buf)[elements] = w; + else /* word_len <= 32 */ + ((u32 *)xfer->rx_buf)[elements] = w; + } else { + dev_err(&spi->dev, "DMA RX last word empty"); + count -= (word_len <= 8) ? 1 : + (word_len <= 16) ? 2 : + /* word_len <= 32 */ 4; + } + omap2_mcspi_set_enable(spi, 1); + return count; +} + +static unsigned +omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) +{ + struct omap2_mcspi *mcspi; + struct omap2_mcspi_cs *cs = spi->controller_state; + struct omap2_mcspi_dma *mcspi_dma; + unsigned int count; + u32 l; + u8 *rx; + const u8 *tx; + struct dma_slave_config cfg; + enum dma_slave_buswidth width; + unsigned es; + + mcspi = spi_master_get_devdata(spi->master); + mcspi_dma = &mcspi->dma_channels[spi->chip_select]; + l = mcspi_cached_chconf0(spi); + + + if (cs->word_len <= 8) { + width = DMA_SLAVE_BUSWIDTH_1_BYTE; + es = 1; + } else if (cs->word_len <= 16) { + width = DMA_SLAVE_BUSWIDTH_2_BYTES; + es = 2; + } else { + width = DMA_SLAVE_BUSWIDTH_4_BYTES; + es = 4; + } + + memset(&cfg, 0, sizeof(cfg)); + cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0; + cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0; + cfg.src_addr_width = width; + cfg.dst_addr_width = width; + cfg.src_maxburst = 1; + cfg.dst_maxburst = 1; + + rx = xfer->rx_buf; + tx = xfer->tx_buf; + + count = xfer->len; + + if (tx != NULL) + omap2_mcspi_tx_dma(spi, xfer, cfg); + + if (rx != NULL) + return omap2_mcspi_rx_dma(spi, xfer, cfg, es); + return count; } |