| Message ID | 1467258867-117727-4-git-send-email-apronin@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
CC devicetree On Thu, Jun 30, 2016 at 5:54 AM, <apronin@chromium.org> wrote: > From: Andrey Pronin <apronin@chromium.org> > > Some devices may need CS to be deasserted for some time > between transactions. Added a new capability to guarantee > a delay between SPI transactions for the device. > > Signed-off-by: Andrey Pronin <apronin@chromium.org> > --- > Documentation/devicetree/bindings/spi/spi-bus.txt | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt b/Documentation/devicetree/bindings/spi/spi-bus.txt > index 1b7ffd4..87c117a 100644 > --- a/Documentation/devicetree/bindings/spi/spi-bus.txt > +++ b/Documentation/devicetree/bindings/spi/spi-bus.txt > @@ -70,6 +70,8 @@ contain the following properties. > sleep if there was no SPI activity (msec). > - cs-wake-duration - (optional) Time it takes the device to wake up after > toggling CS if it went to sleep (msec). > +- xfer-delay - (optional) Delay to insert between SPI transactions > + to guarantee that CS is deasserted at least for some time. > > Some SPI controllers and devices support Dual and Quad SPI transfer mode. > It allows data in the SPI system to be transferred in 2 wires(DUAL) or 4 wires(QUAD). > -- > 2.6.6 -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi, On Thu, Jun 30, 2016 at 12:12 AM, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > CC devicetree > > On Thu, Jun 30, 2016 at 5:54 AM, <apronin@chromium.org> wrote: >> From: Andrey Pronin <apronin@chromium.org> >> >> Some devices may need CS to be deasserted for some time >> between transactions. Added a new capability to guarantee >> a delay between SPI transactions for the device. >> >> Signed-off-by: Andrey Pronin <apronin@chromium.org> >> --- >> Documentation/devicetree/bindings/spi/spi-bus.txt | 2 ++ >> 1 file changed, 2 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt b/Documentation/devicetree/bindings/spi/spi-bus.txt >> index 1b7ffd4..87c117a 100644 >> --- a/Documentation/devicetree/bindings/spi/spi-bus.txt >> +++ b/Documentation/devicetree/bindings/spi/spi-bus.txt >> @@ -70,6 +70,8 @@ contain the following properties. >> sleep if there was no SPI activity (msec). >> - cs-wake-duration - (optional) Time it takes the device to wake up after >> toggling CS if it went to sleep (msec). >> +- xfer-delay - (optional) Delay to insert between SPI transactions >> + to guarantee that CS is deasserted at least for some time. msec? usec? nsec? Also, as with the other patch, this should be _before_ the code change, so this should really be patch 3 not patch 4. -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt b/Documentation/devicetree/bindings/spi/spi-bus.txt index 1b7ffd4..87c117a 100644 --- a/Documentation/devicetree/bindings/spi/spi-bus.txt +++ b/Documentation/devicetree/bindings/spi/spi-bus.txt @@ -70,6 +70,8 @@ contain the following properties. sleep if there was no SPI activity (msec). - cs-wake-duration - (optional) Time it takes the device to wake up after toggling CS if it went to sleep (msec). +- xfer-delay - (optional) Delay to insert between SPI transactions + to guarantee that CS is deasserted at least for some time. Some SPI controllers and devices support Dual and Quad SPI transfer mode. It allows data in the SPI system to be transferred in 2 wires(DUAL) or 4 wires(QUAD).