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Merge remote-tracking branch 'spi/topic/quad' into spi-next

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This commit is contained in:
Mark Brown 2013-09-01 13:49:07 +01:00
parent 85cac43132 a110f93d8b
commit 278ac33bbd
2 changed files with 47 additions and 40 deletions
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10
Documentation/devicetree/bindings/spi/spi-bus.txt
View file

@ -55,6 +55,16 @@ contain the following properties.
chip select active high
- spi-3wire - (optional) Empty property indicating device requires
3-wire mode.
- spi-tx-bus-width - (optional) The bus width(number of data wires) that
used for MOSI. Defaults to 1 if not present.
- spi-rx-bus-width - (optional) The bus width(number of data wires) that
used for MISO. Defaults to 1 if not present.
Some SPI controllers and devices support Dual and Quad SPI transfer mode.
It allows data in SPI system transfered in 2 wires(DUAL) or 4 wires(QUAD).
Now the value that spi-tx-bus-width and spi-rx-bus-width can receive is
only 1(SINGLE), 2(DUAL) and 4(QUAD).
Dual/Quad mode is not allowed when 3-wire mode is used.
If a gpio chipselect is used for the SPI slave the gpio number will be passed
via the cs_gpio

77
drivers/spi/spi.c
View file

@ -886,48 +886,44 @@ static void of_register_spi_devices(struct spi_master *master)
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-tx-bus-width", &len);
if (prop && len == sizeof(*prop)) {
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-bus-width %d not supported\n",
be32_to_cpup(prop));
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;
prop = of_get_property(nc, "spi-rx-bus-width", &len);
if (prop && len == sizeof(*prop)) {
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-bus-width %d not supported\n",
be32_to_cpup(prop));
spi_dev_put(spi);
continue;
}
}
/* Device speed */
@ -1480,6 +1476,7 @@ 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)
return -EINVAL;
if (xfer->tx_buf && !xfer->tx_nbits)
xfer->tx_nbits = SPI_NBITS_SINGLE;