| Message ID | 1378028181-5409-1-git-send-email-wangyuhang2014@gmail.com |
|---|---|
| State | New, archived |
| Headers | show |
On Sun, Sep 01, 2013 at 05:36:21PM +0800, wangyuhang wrote: > spi: quad: fix the name of DT property in patch > > The previous property name spi-tx-nbits and spi-rx-nbits looks not > human-readable. To make it consistent with other devices, using property > name spi-tx-bus-width and spi-rx-bus-width instead of the previous one > specify the number of data wires that spi controller will work in. > Add the specification in spi-bus.txt. Applied, thanks - if there's disagreement about the DT bindings (or indeed other problems) then I can not send this in the final pull request but if it is OK I wanted it to be in -next on Monday.
On 09/01/2013 03:36 AM, wangyuhang wrote: > spi: quad: fix the name of DT property in patch > > The previous property name spi-tx-nbits and spi-rx-nbits looks not > human-readable. To make it consistent with other devices, using property > name spi-tx-bus-width and spi-rx-bus-width instead of the previous one > specify the number of data wires that spi controller will work in. > Add the specification in spi-bus.txt. > diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt b/Documentation/devicetree/bindings/spi/spi-bus.txt > - 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. The binding, Acked-by: Stephen Warren <swarren@nvidia.com> I would have preferred my original wording rather than the unqualified "MOSI"/"MISO", since the meaning of those terms depends on whether you're looking at the host controller or the device, but I guess we can assume that since this is documentation for the host controller binding, the naming is in terms of the host controller's signals.
On Tue, Sep 03, 2013 at 10:53:11AM -0600, Stephen Warren wrote: > I would have preferred my original wording rather than the unqualified > "MOSI"/"MISO", since the meaning of those terms depends on whether > you're looking at the host controller or the device, but I guess we can No, MOSI and MISO have fixed meanings at all ends - they expand to Master Out Slave In and Master In Slave Out so it's always clear which side should be transmitting.
diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt b/Documentation/devicetree/bindings/spi/spi-bus.txt index 296015e..800dafe 100644 --- a/Documentation/devicetree/bindings/spi/spi-bus.txt +++ b/Documentation/devicetree/bindings/spi/spi-bus.txt @@ -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 diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 7557f61..0075318 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -870,7 +870,7 @@ 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); + prop = of_get_property(nc, "spi-tx-bus-width", &len); if (prop && len == sizeof(*prop)) { switch (be32_to_cpup(prop)) { case SPI_NBITS_SINGLE: @@ -883,14 +883,14 @@ static void of_register_spi_devices(struct spi_master *master) break; default: dev_err(&master->dev, - "spi-tx-nbits %d not supported\n", + "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); + prop = of_get_property(nc, "spi-rx-bus-width", &len); if (prop && len == sizeof(*prop)) { switch (be32_to_cpup(prop)) { case SPI_NBITS_SINGLE: @@ -903,7 +903,7 @@ static void of_register_spi_devices(struct spi_master *master) break; default: dev_err(&master->dev, - "spi-rx-nbits %d not supported\n", + "spi-rx-bus-width %d not supported\n", be32_to_cpup(prop)); spi_dev_put(spi); continue;
spi: quad: fix the name of DT property in patch The previous property name spi-tx-nbits and spi-rx-nbits looks not human-readable. To make it consistent with other devices, using property name spi-tx-bus-width and spi-rx-bus-width instead of the previous one specify the number of data wires that spi controller will work in. Add the specification in spi-bus.txt. Signed-off-by: wangyuhang <wangyuhang2014@gmail.com> --- Documentation/devicetree/bindings/spi/spi-bus.txt | 10 ++++++++++ drivers/spi/spi.c | 8 ++++---- 2 files changed, 14 insertions(+), 4 deletions(-)