| Message ID | 20210326081535.1679507-1-linus.walleij@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | gpio: Mention GPIO MUX in docs | expand |
On Fri, Mar 26, 2021 at 9:15 AM Linus Walleij <linus.walleij@linaro.org> wrote: > > There is now a GPIO multiplexer, so mention this in the document > about drivers using GPIO as backend. > > Signed-off-by: Linus Walleij <linus.walleij@linaro.org> > --- > Documentation/driver-api/gpio/drivers-on-gpio.rst | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/Documentation/driver-api/gpio/drivers-on-gpio.rst b/Documentation/driver-api/gpio/drivers-on-gpio.rst > index 41ec3cc72d32..af632d764ac6 100644 > --- a/Documentation/driver-api/gpio/drivers-on-gpio.rst > +++ b/Documentation/driver-api/gpio/drivers-on-gpio.rst > @@ -96,6 +96,12 @@ hardware descriptions such as device tree or ACPI: > way to pass the charging parameters from hardware descriptions such as the > device tree. > > +- gpio-mux: drivers/mux/gpio.c is used for controlling a multiplexer using > + n GPIO lines such that you can mux in 2^n different devices by activating > + different GPIO lines. Often the GPIOs are on a SoC and the devices are > + some SoC-external entities, such as different components on a PCB that > + can be selectively enabled. > + > Apart from this there are special GPIO drivers in subsystems like MMC/SD to > read card detect and write protect GPIO lines, and in the TTY serial subsystem > to emulate MCTRL (modem control) signals CTS/RTS by using two GPIO lines. The > -- > 2.29.2 > Applied, thanks! Bartosz
diff --git a/Documentation/driver-api/gpio/drivers-on-gpio.rst b/Documentation/driver-api/gpio/drivers-on-gpio.rst index 41ec3cc72d32..af632d764ac6 100644 --- a/Documentation/driver-api/gpio/drivers-on-gpio.rst +++ b/Documentation/driver-api/gpio/drivers-on-gpio.rst @@ -96,6 +96,12 @@ hardware descriptions such as device tree or ACPI: way to pass the charging parameters from hardware descriptions such as the device tree. +- gpio-mux: drivers/mux/gpio.c is used for controlling a multiplexer using + n GPIO lines such that you can mux in 2^n different devices by activating + different GPIO lines. Often the GPIOs are on a SoC and the devices are + some SoC-external entities, such as different components on a PCB that + can be selectively enabled. + Apart from this there are special GPIO drivers in subsystems like MMC/SD to read card detect and write protect GPIO lines, and in the TTY serial subsystem to emulate MCTRL (modem control) signals CTS/RTS by using two GPIO lines. The
There is now a GPIO multiplexer, so mention this in the document about drivers using GPIO as backend. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> --- Documentation/driver-api/gpio/drivers-on-gpio.rst | 6 ++++++ 1 file changed, 6 insertions(+)