diff options
Diffstat (limited to 'drivers/spi/spi.c')
| -rw-r--r-- | drivers/spi/spi.c | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 2a20c32c8277..39d38756e984 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -869,6 +869,51 @@ static void of_register_spi_devices(struct spi_master *master) if (of_find_property(nc, "spi-3wire", NULL)) spi->mode |= SPI_3WIRE; + /* Device DUAL/QUAD mode */ + prop = of_get_property(nc, "spi-tx-nbits", &len); + if (!prop || len < sizeof(*prop)) { + dev_err(&master->dev, "%s has no 'spi-tx-nbits' property\n", + nc->full_name); + spi_dev_put(spi); + continue; + } + switch (be32_to_cpup(prop)) { + case SPI_NBITS_SINGLE: + break; + case SPI_NBITS_DUAL: + spi->mode |= SPI_TX_DUAL; + break; + case SPI_NBITS_QUAD: + spi->mode |= SPI_TX_QUAD; + break; + default: + dev_err(&master->dev, "spi-tx-nbits value is not supported\n"); + spi_dev_put(spi); + continue; + } + + prop = of_get_property(nc, "spi-rx-nbits", &len); + if (!prop || len < sizeof(*prop)) { + dev_err(&master->dev, "%s has no 'spi-rx-nbits' property\n", + nc->full_name); + spi_dev_put(spi); + continue; + } + switch (be32_to_cpup(prop)) { + case SPI_NBITS_SINGLE: + break; + case SPI_NBITS_DUAL: + spi->mode |= SPI_RX_DUAL; + break; + case SPI_NBITS_QUAD: + spi->mode |= SPI_RX_QUAD; + break; + default: + dev_err(&master->dev, "spi-rx-nbits value is not supported\n"); + spi_dev_put(spi); + continue; + } + /* Device speed */ prop = of_get_property(nc, "spi-max-frequency", &len); if (!prop || len < sizeof(*prop)) { @@ -1316,6 +1361,19 @@ int spi_setup(struct spi_device *spi) unsigned bad_bits; int status = 0; + /* check mode to prevent that DUAL and QUAD set at the same time + */ + if (((spi->mode & SPI_TX_DUAL) && (spi->mode & SPI_TX_QUAD)) || + ((spi->mode & SPI_RX_DUAL) && (spi->mode & SPI_RX_QUAD))) { + dev_err(&spi->dev, + "setup: can not select dual and quad at the same time\n"); + return -EINVAL; + } + /* if it is SPI_3WIRE mode, DUAL and QUAD should be forbidden + */ + if ((spi->mode & SPI_3WIRE) && (spi->mode & + (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD))) + return -EINVAL; /* help drivers fail *cleanly* when they need options * that aren't supported with their current master */ @@ -1378,6 +1436,8 @@ static int __spi_async(struct spi_device *spi, struct spi_message *message) /** * Set transfer bits_per_word and max speed as spi device default if * it is not set for this transfer. + * Set transfer tx_nbits and rx_nbits as single transfer default + * (SPI_NBITS_SINGLE) if it is not set for this transfer. */ list_for_each_entry(xfer, &message->transfers, transfer_list) { if (!xfer->bits_per_word) @@ -1403,6 +1463,42 @@ static int __spi_async(struct spi_device *spi, struct spi_message *message) return -EINVAL; if (xfer->speed_hz && master->max_speed_hz && xfer->speed_hz > master->max_speed_hz) + + if (xfer->tx_buf && !xfer->tx_nbits) + xfer->tx_nbits = SPI_NBITS_SINGLE; + if (xfer->rx_buf && !xfer->rx_nbits) + xfer->rx_nbits = SPI_NBITS_SINGLE; + /* check transfer tx/rx_nbits: + * 1. keep the value is not out of single, dual and quad + * 2. keep tx/rx_nbits is contained by mode in spi_device + * 3. if SPI_3WIRE, tx/rx_nbits should be in single + */ + if (xfer->tx_nbits != SPI_NBITS_SINGLE && + xfer->tx_nbits != SPI_NBITS_DUAL && + xfer->tx_nbits != SPI_NBITS_QUAD) + return -EINVAL; + if ((xfer->tx_nbits == SPI_NBITS_DUAL) && + !(spi->mode & (SPI_TX_DUAL | SPI_TX_QUAD))) + return -EINVAL; + if ((xfer->tx_nbits == SPI_NBITS_QUAD) && + !(spi->mode & SPI_TX_QUAD)) + return -EINVAL; + if ((spi->mode & SPI_3WIRE) && + (xfer->tx_nbits != SPI_NBITS_SINGLE)) + return -EINVAL; + /* check transfer rx_nbits */ + if (xfer->rx_nbits != SPI_NBITS_SINGLE && + xfer->rx_nbits != SPI_NBITS_DUAL && + xfer->rx_nbits != SPI_NBITS_QUAD) + return -EINVAL; + if ((xfer->rx_nbits == SPI_NBITS_DUAL) && + !(spi->mode & (SPI_RX_DUAL | SPI_RX_QUAD))) + return -EINVAL; + if ((xfer->rx_nbits == SPI_NBITS_QUAD) && + !(spi->mode & SPI_RX_QUAD)) + return -EINVAL; + if ((spi->mode & SPI_3WIRE) && + (xfer->rx_nbits != SPI_NBITS_SINGLE)) return -EINVAL; } |