drivers: gpio: Add driver for pcf8574

Adds a driver for pcf8574 via i2c.

Signed-off-by: Josia Strack <[email protected]>

Author: jstr00

drivers/gpio/CMakeLists.txt

@@ -48,6 +48,7 @@ zephyr_library_sources_ifdef(CONFIG_GPIO_SNPS_CREG  gpio_creg_gpio.c)
 zephyr_library_sources_ifdef(CONFIG_GPIO_STMPE1600  gpio_stmpe1600.c)
 zephyr_library_sources_ifdef(CONFIG_GPIO_XEC_V2     gpio_mchp_xec_v2.c)
 zephyr_library_sources_ifdef(CONFIG_GPIO_PCA953X    gpio_pca953x.c)
+zephyr_library_sources_ifdef(CONFIG_GPIO_PCF8574    gpio_pcf8574.c)
 zephyr_library_sources_ifdef(CONFIG_GPIO_FXL6408    gpio_fxl6408.c)
 zephyr_library_sources_ifdef(CONFIG_GPIO_ANDES_ATCGPIO100 gpio_andes_atcgpio100.c)
 zephyr_library_sources_ifdef(CONFIG_GPIO_NEORV32    gpio_neorv32.c)

drivers/gpio/Kconfig

@@ -128,6 +128,8 @@ source "drivers/gpio/Kconfig.stmpe1600"
 
 source "drivers/gpio/Kconfig.pca953x"
 
+source "drivers/gpio/Kconfig.pcf8574"
+
 source "drivers/gpio/Kconfig.fxl6408"
 
 source "drivers/gpio/Kconfig.andes_atcgpio100"

drivers/gpio/Kconfig.pcf8574

@@ -0,0 +1,19 @@
+# PCF8574 GPIO configuration options
+
+# Copyright (c) 2022 Ithinx
+# SPDX-License-Identifier: Apache-2.0
+
+menuconfig GPIO_PCF8574
+	bool "PCF8574 I2C GPIO chip"
+	default y
+	depends on DT_HAS_NXP_PCF8574_ENABLED
+	select I2C
+	help
+	  Enable driver for PCF8574 I2C GPIO chip.
+
+config GPIO_PCF8574_INIT_PRIORITY
+	int "Init priority"
+	default 70
+	depends on GPIO_PCF8574
+	help
+	  Device driver initialization priority.