diff options
Diffstat (limited to 'drivers/spi/spi-dw-core.c')
| -rw-r--r-- | drivers/spi/spi-dw-core.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/drivers/spi/spi-dw-core.c b/drivers/spi/spi-dw-core.c index 0274c9295514..ddfdb903047a 100644 --- a/drivers/spi/spi-dw-core.c +++ b/drivers/spi/spi-dw-core.c @@ -6,6 +6,7 @@ */ #include <linux/bitfield.h> +#include <linux/bitops.h> #include <linux/dma-mapping.h> #include <linux/interrupt.h> #include <linux/module.h> @@ -421,10 +422,7 @@ static int dw_spi_transfer_one(struct spi_controller *host, int ret; dws->dma_mapped = 0; - dws->n_bytes = - roundup_pow_of_two(DIV_ROUND_UP(transfer->bits_per_word, - BITS_PER_BYTE)); - + dws->n_bytes = roundup_pow_of_two(BITS_TO_BYTES(transfer->bits_per_word)); dws->tx = (void *)transfer->tx_buf; dws->tx_len = transfer->len / dws->n_bytes; dws->rx = transfer->rx_buf; @@ -837,6 +835,20 @@ static void dw_spi_hw_init(struct device *dev, struct dw_spi *dws) } /* + * Try to detect the number of native chip-selects if the platform + * driver didn't set it up. There can be up to 16 lines configured. + */ + if (!dws->num_cs) { + u32 ser; + + dw_writel(dws, DW_SPI_SER, 0xffff); + ser = dw_readl(dws, DW_SPI_SER); + dw_writel(dws, DW_SPI_SER, 0); + + dws->num_cs = hweight16(ser); + } + + /* * Try to detect the FIFO depth if not set by interface driver, * the depth could be from 2 to 256 from HW spec */ |