drivers: add PCF857X I2C I/O expander driver

drivers/Kconfig

@@ -42,6 +42,7 @@ rsource "ds3231/Kconfig"
 rsource "ds3234/Kconfig"
 rsource "edbg_eui/Kconfig"
 rsource "io1_xplained/Kconfig"
+rsource "pcf857x/Kconfig"
 rsource "tps6274x/Kconfig"
 rsource "uart_half_duplex/Kconfig"
 rsource "usbdev_mock/Kconfig"

drivers/Makefile.dep

@@ -113,6 +113,10 @@ ifneq (,$(filter nrf24l01p_ng_%,$(USEMODULE)))
   USEMODULE += nrf24l01p_ng
 endif
 
+ifneq (,$(filter pcf857%,$(USEMODULE)))
+  USEMODULE += pcf857x
+endif
+
 ifneq (,$(filter periph_ptp_timer periph_ptp_speed_adjustment,$(FEATURES_USED)))
   FEATURES_REQUIRED += periph_ptp
 endif

drivers/pcf857x/Kconfig

@@ -0,0 +1,65 @@
+# Copyright (c) 2021 Gunar Schorcht
+#
+# This file is subject to the terms and conditions of the GNU Lesser
+# General Public License v2.1. See the file LICENSE in the top level
+# directory for more details.
+#
+
+menuconfig MODULE_PCF857X
+    bool "PCF857x Remote I/O Expander for I2C Bus"
+    depends on HAS_PERIPH_GPIO
+    depends on HAS_PERIPH_I2C
+    depends on TEST_KCONFIG
+    select MODULE_PERIPH_GPIO
+    select MODULE_PERIPH_I2C
+    help
+        Driver for Texas Instruments PCF857X I2C I/O expanders.
+        The driver supports the PCF8574, PCF8574A, and PCF8575 variants.
+        Select the variants used by your application.
+
+if MODULE_PCF857X
+
+config MODULE_PCF8574
+    bool "PCF8574  Remote  8-Bit I/O is used"
+
+config MODULE_PCF8574A
+    bool "PCF8574A Remote  8-Bit I/O is used"
+
+config MODULE_PCF8575
+    bool "PCF8575  Remote 16-Bit I/O is used"
+    default y
+
+config MODULE_PCF857X_IRQ
+    bool "Interrupt support for PCF857x I/O Expander pins"
+    depends on MODULE_PCF857X
+    depends on HAS_PERIPH_GPIO_IRQ
+    select MODULE_PERIPH_GPIO_IRQ
+    select MODULE_EVENT
+    select MODULE_EVENT_THREAD
+    help
+        To use the IRQs the MODULE_EVENT_THREAD symbol should be set.
+
+choice
+    bool "Thread priority"
+    depends on MODULE_PCF857X_IRQ
+    default MODULE_PCF857X_IRQ_MEDIUM
+    help
+        To process IRQs an event thread is used. The MODULE_EVENT_THREAD
+        symbol should be set. Choose a priority for the thread that
+        processes the IRQs. The default is medium priority.
+
+config MODULE_PCF857X_IRQ_LOW
+    bool "Low"
+    select MODULE_EVENT_THREAD_LOW
+
+config MODULE_PCF857X_IRQ_MEDIUM
+    bool "Medium"
+    select MODULE_EVENT_THREAD_MEDIUM
+
+config MODULE_PCF857X_IRQ_HIGHEST
+    bool "Highest"
+    select MODULE_EVENT_THREAD_HIGHEST
+
+endchoice
+
+endif # MODULE_PCF857X

drivers/pcf857x/Makefile

@@ -0,0 +1 @@
+include $(RIOTBASE)/Makefile.base

drivers/pcf857x/Makefile.dep

@@ -0,0 +1,19 @@
+FEATURES_REQUIRED += periph_gpio
+FEATURES_REQUIRED += periph_i2c
+
+_PCF857X_IRQ_MODULE := $(filter pcf857x_irq_%,$(USEMODULE))
+ifneq (,$(_PCF857X_IRQ_MODULE))
+  # pull in the correspondant event_thread_<priority> module
+  USEMODULE += $(_PCF857X_IRQ_MODULE:pcf857x_irq_%=event_thread_%)
+  USEMODULE += pcf857x_irq
+else
+  ifneq (,$(filter pcf857x_irq,$(USEMODULE)))
+    # pull in the pcf857x_irq_medium module as default if pcf857x_irq is used.
+    USEMODULE += pcf857x_irq_medium
+  endif
+endif
+
+ifneq (,$(filter pcf857x_irq,$(USEMODULE)))
+  FEATURES_REQUIRED += periph_gpio_irq
+  USEMODULE += pcf857x
+endif

drivers/pcf857x/Makefile.include

@@ -0,0 +1,11 @@
+# include variants of PCF857X drivers as pseudo modules
+PSEUDOMODULES += pcf8574
+PSEUDOMODULES += pcf8574a
+PSEUDOMODULES += pcf8575
+PSEUDOMODULES += pcf857x_irq
+PSEUDOMODULES += pcf857x_irq_low
+PSEUDOMODULES += pcf857x_irq_medium
+PSEUDOMODULES += pcf857x_irq_highest
+
+USEMODULE_INCLUDES_pcf857x := $(LAST_MAKEFILEDIR)/include
+USEMODULE_INCLUDES += $(USEMODULE_INCLUDES_pcf857x)

drivers/pcf857x/include/pcf857x_params.h

@@ -0,0 +1,123 @@
+/*
+ * Copyright (C) 2018 Gunar Schorcht
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     drivers_pcf857x
+ * @brief       Default configuration for Texas Instruments PCF857X I2C I/O expanders
+ * @author      Gunar Schorcht <gunar@schorcht.net>
+ * @file
+ * @{
+ */
+
+#ifndef PCF857X_PARAMS_H
+#define PCF857X_PARAMS_H
+
+#include "board.h"
+#include "pcf857x.h"
+#include "saul_reg.h"
+#include "saul/periph.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @name    Set default configuration parameters
+ * @{
+ */
+#ifndef PCF857X_PARAM_DEV
+/** device is I2C_DEV(0) */
+#define PCF857X_PARAM_DEV       I2C_DEV(0)
+#endif
+
+#ifndef PCF857X_PARAM_ADDR
+/** I2C slave address offset is 0 */
+#define PCF857X_PARAM_ADDR      (0)
+#endif
+
+#ifndef PCF857X_PARAM_EXP
+/** PCF857X expander variant used depends on enabled pseudomodules*/
+#if IS_USED(MODULE_PCF8575) || DOXYGEN
+#define PCF857X_PARAM_EXP       (PCF857X_EXP_PCF8575)
+#elif IS_USED(MODULE_PCF8574)
+#define PCF857X_PARAM_EXP       (PCF857X_EXP_PCF8574)
+#elif IS_USED(MODULE_PCF8574A)
+#define PCF857X_PARAM_EXP       (PCF857X_EXP_PCF8574A)
+#endif
+#endif /* PCF857X_PARAM_EXP */
+
+#ifndef PCF857X_PARAM_INT_PIN
+/** MCU interrupt pin */
+#define PCF857X_PARAM_INT_PIN   (GPIO_UNDEF)
+#endif
+
+#ifndef PCF857X_PARAMS
+#if IS_USED(MODULE_PCF857X_IRQ) || DOXYGEN
+/** Default configuration parameter set */
+#define PCF857X_PARAMS { \
+                            .dev = PCF857X_PARAM_DEV, \
+                            .addr = PCF857X_PARAM_ADDR, \
+                            .exp = PCF857X_PARAM_EXP, \
+                            .int_pin = PCF857X_PARAM_INT_PIN, \
+                        },
+#else
+#define PCF857X_PARAMS { \
+                            .dev = PCF857X_PARAM_DEV, \
+                            .addr = PCF857X_PARAM_ADDR, \
+                            .exp = PCF857X_PARAM_EXP, \
+                        },
+#endif
+#endif /* PCF857X_PARAMS */
+
+#ifndef PCF857X_SAUL_GPIO_PARAMS
+/** Example for mapping expander pins to SAUL */
+#define PCF857X_SAUL_GPIO_PARAMS { \
+                                        .dev = 0, \
+                                        .gpio = { \
+                                            .name = "P00 Output", \
+                                            .pin = PCF857X_GPIO_PIN(0, 0), \
+                                            .mode = GPIO_OUT, \
+                                            .flags = SAUL_GPIO_INIT_CLEAR, \
+                                        } \
+                                 }, \
+                                 { \
+                                        .dev = 0, \
+                                        .gpio = { \
+                                            .name = "P01 Input", \
+                                            .pin = PCF857X_GPIO_PIN(0, 1), \
+                                            .mode = GPIO_IN, \
+                                            .flags = 0, \
+                                        } \
+                                 },
+#endif
+/**@}*/
+
+/**
+ * @brief   Allocate some memory to store the actual configuration
+ */
+static const pcf857x_params_t pcf857x_params[] =
+{
+    PCF857X_PARAMS
+};
+
+#if IS_USED(MODULE_SAUL_GPIO) || DOXYGEN
+/**
+ * @brief   Additional meta information to keep in the SAUL registry
+ */
+static const  pcf857x_saul_gpio_params_t pcf857x_saul_gpio_params[] =
+{
+    PCF857X_SAUL_GPIO_PARAMS
+};
+#endif /* MODULE_SAUL_GPIO || DOXYGEN */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* PCF857X_PARAMS_H */
+/** @} */