diff options
author | Linus Walleij <linus.walleij@linaro.org> | 2021-03-26 09:15:35 +0100 |
---|---|---|
committer | Bartosz Golaszewski <bgolaszewski@baylibre.com> | 2021-03-26 14:56:19 +0100 |
commit | 4a5c9da4ec29bc2a4fff00c2c36ce38826123d68 (patch) | |
tree | 3b0a9802fcab2247f7e6688fc440592d47094c64 /Documentation | |
parent | 81dd500b1c8612a42979ee3ea788d2d9f19aa9f9 (diff) |
gpio: Mention GPIO MUX in docs
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>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/driver-api/gpio/drivers-on-gpio.rst | 6 |
1 files changed, 6 insertions, 0 deletions
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 |