diff options
Diffstat (limited to 'drivers/spi/spi-atmel.c')
-rw-r--r-- | drivers/spi/spi-atmel.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c index f53f0c5e63da..4954f0ab1606 100644 --- a/drivers/spi/spi-atmel.c +++ b/drivers/spi/spi-atmel.c | |||
@@ -1201,13 +1201,14 @@ static int atmel_spi_setup(struct spi_device *spi) | |||
1201 | csr |= SPI_BIT(CSAAT); | 1201 | csr |= SPI_BIT(CSAAT); |
1202 | 1202 | ||
1203 | /* DLYBS is mostly irrelevant since we manage chipselect using GPIOs. | 1203 | /* DLYBS is mostly irrelevant since we manage chipselect using GPIOs. |
1204 | * | ||
1205 | * DLYBCT would add delays between words, slowing down transfers. | ||
1206 | * It could potentially be useful to cope with DMA bottlenecks, but | ||
1207 | * in those cases it's probably best to just use a lower bitrate. | ||
1208 | */ | 1204 | */ |
1209 | csr |= SPI_BF(DLYBS, 0); | 1205 | csr |= SPI_BF(DLYBS, 0); |
1210 | csr |= SPI_BF(DLYBCT, 0); | 1206 | |
1207 | /* DLYBCT adds delays between words. This is useful for slow devices | ||
1208 | * that need a bit of time to setup the next transfer. | ||
1209 | */ | ||
1210 | csr |= SPI_BF(DLYBCT, | ||
1211 | (as->spi_clk / 1000000 * spi->word_delay_usecs) >> 5); | ||
1211 | 1212 | ||
1212 | asd = spi->controller_state; | 1213 | asd = spi->controller_state; |
1213 | if (!asd) { | 1214 | if (!asd) { |