diff options
| -rw-r--r-- | drivers/spi/spi.c | 12 | ||||
| -rw-r--r-- | include/linux/spi/spi.h | 2 |
2 files changed, 11 insertions, 3 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 97487e1f27b5..c582ae4deab3 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1435,7 +1435,8 @@ static int spi_transfer_one_message(struct spi_controller *ctlr, struct spi_statistics __percpu *statm = ctlr->pcpu_statistics; struct spi_statistics __percpu *stats = msg->spi->pcpu_statistics; - spi_set_cs(msg->spi, true, false); + xfer = list_first_entry(&msg->transfers, struct spi_transfer, transfer_list); + spi_set_cs(msg->spi, !xfer->cs_off, false); SPI_STATISTICS_INCREMENT_FIELD(statm, messages); SPI_STATISTICS_INCREMENT_FIELD(stats, messages); @@ -1503,10 +1504,15 @@ fallback_pio: &msg->transfers)) { keep_cs = true; } else { - spi_set_cs(msg->spi, false, false); + if (!xfer->cs_off) + spi_set_cs(msg->spi, false, false); _spi_transfer_cs_change_delay(msg, xfer); - spi_set_cs(msg->spi, true, false); + if (!list_next_entry(xfer, transfer_list)->cs_off) + spi_set_cs(msg->spi, true, false); } + } else if (!list_is_last(&xfer->transfer_list, &msg->transfers) && + xfer->cs_off != list_next_entry(xfer, transfer_list)->cs_off) { + spi_set_cs(msg->spi, xfer->cs_off, false); } msg->actual_length += xfer->len; diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index e6c73d5ff1a8..6e6c62c59957 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -847,6 +847,7 @@ struct spi_res { * for this transfer. If 0 the default (from @spi_device) is used. * @dummy_data: indicates transfer is dummy bytes transfer. * @cs_change: affects chipselect after this transfer completes + * @cs_off: performs the transfer with chipselect off. * @cs_change_delay: delay between cs deassert and assert when * @cs_change is set and @spi_transfer is not the last in @spi_message * @delay: delay to be introduced after this transfer before @@ -959,6 +960,7 @@ struct spi_transfer { unsigned cs_change:1; unsigned tx_nbits:3; unsigned rx_nbits:3; + unsigned cs_off:1; #define SPI_NBITS_SINGLE 0x01 /* 1bit transfer */ #define SPI_NBITS_DUAL 0x02 /* 2bits transfer */ #define SPI_NBITS_QUAD 0x04 /* 4bits transfer */ |