diff options
Diffstat (limited to 'drivers/spi/spi-dw.c')
| -rw-r--r-- | drivers/spi/spi-dw.c | 46 |
1 files changed, 34 insertions, 12 deletions
diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c index 9a49e073e8b7..c2f96941ad04 100644 --- a/drivers/spi/spi-dw.c +++ b/drivers/spi/spi-dw.c @@ -128,11 +128,20 @@ void dw_spi_set_cs(struct spi_device *spi, bool enable) { struct dw_spi *dws = spi_controller_get_devdata(spi->controller); struct chip_data *chip = spi_get_ctldata(spi); + bool cs_high = !!(spi->mode & SPI_CS_HIGH); + /* Chip select logic is inverted from spi_set_cs() */ if (chip && chip->cs_control) - chip->cs_control(enable); + chip->cs_control(!enable); - if (enable) + /* + * DW SPI controller demands any native CS being set in order to + * proceed with data transfer. So in order to activate the SPI + * communications we must set a corresponding bit in the Slave + * Enable register no matter whether the SPI core is configured to + * support active-high or active-low CS level. + */ + if (cs_high == enable) dw_writel(dws, DW_SPI_SER, BIT(spi->chip_select)); else if (dws->cs_override) dw_writel(dws, DW_SPI_SER, 0); @@ -171,9 +180,11 @@ static inline u32 rx_max(struct dw_spi *dws) static void dw_writer(struct dw_spi *dws) { - u32 max = tx_max(dws); + u32 max; u16 txw = 0; + spin_lock(&dws->buf_lock); + max = tx_max(dws); while (max--) { /* Set the tx word if the transfer's original "tx" is not null */ if (dws->tx_end - dws->len) { @@ -185,13 +196,16 @@ static void dw_writer(struct dw_spi *dws) dw_write_io_reg(dws, DW_SPI_DR, txw); dws->tx += dws->n_bytes; } + spin_unlock(&dws->buf_lock); } static void dw_reader(struct dw_spi *dws) { - u32 max = rx_max(dws); + u32 max; u16 rxw; + spin_lock(&dws->buf_lock); + max = rx_max(dws); while (max--) { rxw = dw_read_io_reg(dws, DW_SPI_DR); /* Care rx only if the transfer's original "rx" is not null */ @@ -203,6 +217,7 @@ static void dw_reader(struct dw_spi *dws) } dws->rx += dws->n_bytes; } + spin_unlock(&dws->buf_lock); } static void int_error_stop(struct dw_spi *dws, const char *msg) @@ -275,18 +290,23 @@ static int dw_spi_transfer_one(struct spi_controller *master, { struct dw_spi *dws = spi_controller_get_devdata(master); struct chip_data *chip = spi_get_ctldata(spi); + unsigned long flags; u8 imask = 0; u16 txlevel = 0; u32 cr0; int ret; dws->dma_mapped = 0; - + spin_lock_irqsave(&dws->buf_lock, flags); dws->tx = (void *)transfer->tx_buf; dws->tx_end = dws->tx + transfer->len; dws->rx = transfer->rx_buf; dws->rx_end = dws->rx + transfer->len; dws->len = transfer->len; + spin_unlock_irqrestore(&dws->buf_lock, flags); + + /* Ensure dw->rx and dw->rx_end are visible */ + smp_mb(); spi_enable_chip(dws, 0); @@ -308,7 +328,8 @@ static int dw_spi_transfer_one(struct spi_controller *master, cr0 = (transfer->bits_per_word - 1) | (chip->type << SPI_FRF_OFFSET) | ((((spi->mode & SPI_CPOL) ? 1 : 0) << SPI_SCOL_OFFSET) | - (((spi->mode & SPI_CPHA) ? 1 : 0) << SPI_SCPH_OFFSET)) + (((spi->mode & SPI_CPHA) ? 1 : 0) << SPI_SCPH_OFFSET) | + (((spi->mode & SPI_LOOP) ? 1 : 0) << SPI_SRL_OFFSET)) | (chip->tmode << SPI_TMOD_OFFSET); /* @@ -360,11 +381,8 @@ static int dw_spi_transfer_one(struct spi_controller *master, spi_enable_chip(dws, 1); - if (dws->dma_mapped) { - ret = dws->dma_ops->dma_transfer(dws, transfer); - if (ret < 0) - return ret; - } + if (dws->dma_mapped) + return dws->dma_ops->dma_transfer(dws, transfer); if (chip->poll_mode) return poll_transfer(dws); @@ -469,6 +487,7 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws) dws->type = SSI_MOTO_SPI; dws->dma_inited = 0; dws->dma_addr = (dma_addr_t)(dws->paddr + DW_SPI_DR); + spin_lock_init(&dws->buf_lock); spi_controller_set_devdata(master, dws); @@ -507,10 +526,11 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws) dws->dma_inited = 0; } else { master->can_dma = dws->dma_ops->can_dma; + master->flags |= SPI_CONTROLLER_MUST_TX; } } - ret = devm_spi_register_controller(dev, master); + ret = spi_register_controller(master); if (ret) { dev_err(&master->dev, "problem registering spi master\n"); goto err_dma_exit; @@ -534,6 +554,8 @@ void dw_spi_remove_host(struct dw_spi *dws) { dw_spi_debugfs_remove(dws); + spi_unregister_controller(dws->master); + if (dws->dma_ops && dws->dma_ops->dma_exit) dws->dma_ops->dma_exit(dws); |