hw/gpio: introduce pcf8574 driver

NXP PCF8574 and compatible ICs are simple I2C GPIO expanders.
PCF8574 incorporates quasi-bidirectional IO, and simple
communication protocol, when IO read is I2C byte read, and
IO write is I2C byte write. User can think of it as
open-drain port, when line high state is input and line low
state is output.

Signed-off-by: Dmitrii Sharikhin <d.sharikhin@yadro.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <f1552d822276e878d84c01eba2cf2c7c9ebdde00.camel@yadro.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
This commit is contained in:
Dmitriy Sharikhin 2024-03-11 09:58:31 +00:00 committed by Philippe Mathieu-Daudé
parent 2ea09fe85a
commit 4cbb1513a2
5 changed files with 188 additions and 0 deletions

View file

@ -16,3 +16,4 @@ system_ss.add(when: 'CONFIG_RASPI', if_true: files(
system_ss.add(when: 'CONFIG_STM32L4X5_SOC', if_true: files('stm32l4x5_gpio.c'))
system_ss.add(when: 'CONFIG_ASPEED_SOC', if_true: files('aspeed_gpio.c'))
system_ss.add(when: 'CONFIG_SIFIVE_GPIO', if_true: files('sifive_gpio.c'))
system_ss.add(when: 'CONFIG_PCF8574', if_true: files('pcf8574.c'))