From 647110e5e5adef98a133f5f65b212110e614309b Mon Sep 17 00:00:00 2001
From: Pete Johanson <peter@peterjohanson.com>
Date: Thu, 28 Jan 2021 22:54:44 -0500
Subject: [PATCH] feat(drivers): Add mcp23017 driver based on upstream mcp23s17
one.
* Upstream Zephyr has in progress driver, so doing this locally here,
until we can move over to that driver.
---
app/drivers/CMakeLists.txt | 3 +-
app/drivers/Kconfig | 3 +-
app/drivers/gpio/CMakeLists.txt | 8 +
app/drivers/gpio/Kconfig | 1 +
app/drivers/gpio/Kconfig.mcp23017 | 21 ++
app/drivers/gpio/gpio_mcp23017.c | 332 ++++++++++++++++++
app/drivers/gpio/gpio_mcp23017.h | 86 +++++
.../dts/bindings/gpio/microchip,mcp23017.yaml | 29 ++
8 files changed, 481 insertions(+), 2 deletions(-)
create mode 100644 app/drivers/gpio/CMakeLists.txt
create mode 100644 app/drivers/gpio/Kconfig
create mode 100644 app/drivers/gpio/Kconfig.mcp23017
create mode 100644 app/drivers/gpio/gpio_mcp23017.c
create mode 100644 app/drivers/gpio/gpio_mcp23017.h
create mode 100644 app/drivers/zephyr/dts/bindings/gpio/microchip,mcp23017.yaml
diff --git a/app/drivers/CMakeLists.txt b/app/drivers/CMakeLists.txt
index c1625f2f..c58ada48 100644
--- a/app/drivers/CMakeLists.txt
+++ b/app/drivers/CMakeLists.txt
@@ -1,6 +1,7 @@
# Copyright (c) 2020 The ZMK Contributors
# SPDX-License-Identifier: MIT
+add_subdirectory(gpio)
add_subdirectory(kscan)
add_subdirectory(sensor)
-add_subdirectory(display)
\ No newline at end of file
+add_subdirectory(display)
diff --git a/app/drivers/Kconfig b/app/drivers/Kconfig
index 5bcc522d..c57ed334 100644
--- a/app/drivers/Kconfig
+++ b/app/drivers/Kconfig
@@ -1,6 +1,7 @@
# Copyright (c) 2020 The ZMK Contributors
# SPDX-License-Identifier: MIT
+rsource "gpio/Kconfig"
rsource "kscan/Kconfig"
rsource "sensor/Kconfig"
-rsource "display/Kconfig"
\ No newline at end of file
+rsource "display/Kconfig"
diff --git a/app/drivers/gpio/CMakeLists.txt b/app/drivers/gpio/CMakeLists.txt
new file mode 100644
index 00000000..b879b238
--- /dev/null
+++ b/app/drivers/gpio/CMakeLists.txt
@@ -0,0 +1,8 @@
+# Copyright (c) 2020 The ZMK Contributors
+# SPDX-License-Identifier: MIT
+
+zephyr_library_named(zmk__drivers__gpio)
+zephyr_library_include_directories(${CMAKE_SOURCE_DIR}/include)
+
+zephyr_library_sources_ifdef(CONFIG_GPIO_MCP23017 gpio_mcp23017.c)
+zephyr_library_sources_ifndef(CONFIG_GPIO_MCP23017 ${ZEPHYR_BASE}/misc/empty_file.c)
diff --git a/app/drivers/gpio/Kconfig b/app/drivers/gpio/Kconfig
new file mode 100644
index 00000000..09f9609f
--- /dev/null
+++ b/app/drivers/gpio/Kconfig
@@ -0,0 +1 @@
+rsource "Kconfig.mcp23017"
diff --git a/app/drivers/gpio/Kconfig.mcp23017 b/app/drivers/gpio/Kconfig.mcp23017
new file mode 100644
index 00000000..4953b924
--- /dev/null
+++ b/app/drivers/gpio/Kconfig.mcp23017
@@ -0,0 +1,21 @@
+# MCP23017 GPIO configuration options
+
+# Copyright (c) 2021 Pete Johanson
+# SPDX-License-Identifier: Apache-2.0
+
+menuconfig GPIO_MCP23017
+ bool "MCP23017 I2C-based GPIO chip"
+ depends on I2C
+ select HAS_DTS_GPIO
+ help
+ Enable driver for MCP23017 I2C-based GPIO chip.
+
+if GPIO_MCP23017
+
+config GPIO_MCP23017_INIT_PRIORITY
+ int "Init priority"
+ default 75
+ help
+ Device driver initialization priority.
+
+endif #GPIO_MCP23017
diff --git a/app/drivers/gpio/gpio_mcp23017.c b/app/drivers/gpio/gpio_mcp23017.c
new file mode 100644
index 00000000..eb38ce50
--- /dev/null
+++ b/app/drivers/gpio/gpio_mcp23017.c
@@ -0,0 +1,332 @@
+/*
+ * Copyright (c) 2020 Geanix ApS
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#define DT_DRV_COMPAT microchip_mcp23017
+
+/**
+ * @file Driver for MCP23017 SPI-based GPIO driver.
+ */
+
+#include <errno.h>
+
+#include <kernel.h>
+#include <device.h>
+#include <init.h>
+#include <sys/byteorder.h>
+#include <drivers/gpio.h>
+#include <drivers/i2c.h>
+
+#include "gpio_mcp23017.h"
+
+#define LOG_LEVEL CONFIG_GPIO_LOG_LEVEL
+#include <logging/log.h>
+LOG_MODULE_REGISTER(gpio_mcp23017);
+
+/**
+ * @brief Read both port 0 and port 1 registers of certain register function.
+ *
+ * Given the register in reg, read the pair of port 0 and port 1.
+ *
+ * @param dev Device struct of the MCP23017.
+ * @param reg Register to read (the PORTA of the pair of registers).
+ * @param buf Buffer to read data into.
+ *
+ * @return 0 if successful, failed otherwise.
+ */
+static int read_port_regs(const struct device *dev, uint8_t reg, uint16_t *buf) {
+ const struct mcp23017_config *const config = dev->config;
+ struct mcp23017_drv_data *const drv_data = (struct mcp23017_drv_data *const)dev->data;
+ int ret;
+ uint16_t port_data;
+
+ uint8_t addr = config->slave;
+
+ ret = i2c_burst_read(drv_data->i2c, addr, reg, (uint8_t *)&port_data, sizeof(port_data));
+ if (ret) {
+ LOG_DBG("i2c_write_read FAIL %d\n", ret);
+ return ret;
+ }
+
+ *buf = sys_le16_to_cpu(port_data);
+
+ LOG_DBG("MCP23017: Read: REG[0x%X] = 0x%X, REG[0x%X] = 0x%X", reg, (*buf & 0xFF), (reg + 1),
+ (*buf >> 8));
+
+ return 0;
+}
+
+/**
+ * @brief Write both port 0 and port 1 registers of certain register function.
+ *
+ * Given the register in reg, write the pair of port 0 and port 1.
+ *
+ * @param dev Device struct of the MCP23017.
+ * @param reg Register to write into (the PORTA of the pair of registers).
+ * @param buf Buffer to write data from.
+ *
+ * @return 0 if successful, failed otherwise.
+ */
+static int write_port_regs(const struct device *dev, uint8_t reg, uint16_t value) {
+ const struct mcp23017_config *const config = dev->config;
+ struct mcp23017_drv_data *const drv_data = (struct mcp23017_drv_data *const)dev->data;
+ int ret;
+ uint16_t port_data;
+
+ LOG_DBG("MCP23017: Write: REG[0x%X] = 0x%X, REG[0x%X] = 0x%X", reg, (value & 0xFF), (reg + 1),
+ (value >> 8));
+
+ port_data = sys_cpu_to_le16(value);
+
+ ret = i2c_burst_write(drv_data->i2c, config->slave, reg, (uint8_t *)&port_data,
+ sizeof(port_data));
+ if (ret) {
+ LOG_DBG("i2c_write FAIL %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+/**
+ * @brief Setup the pin direction (input or output)
+ *
+ * @param dev Device struct of the MCP23017
+ * @param pin The pin number
+ * @param flags Flags of pin or port
+ *
+ * @return 0 if successful, failed otherwise
+ */
+static int setup_pin_dir(const struct device *dev, uint32_t pin, int flags) {
+ struct mcp23017_drv_data *const drv_data = (struct mcp23017_drv_data *const)dev->data;
+ uint16_t *dir = &drv_data->reg_cache.iodir;
+ uint16_t *output = &drv_data->reg_cache.gpio;
+ int ret;
+
+ if ((flags & GPIO_OUTPUT) != 0U) {
+ if ((flags & GPIO_OUTPUT_INIT_HIGH) != 0U) {
+ *output |= BIT(pin);
+ } else if ((flags & GPIO_OUTPUT_INIT_LOW) != 0U) {
+ *output &= ~BIT(pin);
+ }
+ *dir &= ~BIT(pin);
+ } else {
+ *dir |= BIT(pin);
+ }
+
+ ret = write_port_regs(dev, REG_GPIO_PORTA, *output);
+ if (ret != 0) {
+ return ret;
+ }
+
+ ret = write_port_regs(dev, REG_IODIR_PORTA, *dir);
+
+ return ret;
+}
+
+/**
+ * @brief Setup the pin pull up/pull down status
+ *
+ * @param dev Device struct of the MCP23017
+ * @param pin The pin number
+ * @param flags Flags of pin or port
+ *
+ * @return 0 if successful, failed otherwise
+ */
+static int setup_pin_pullupdown(const struct device *dev, uint32_t pin, int flags) {
+ struct mcp23017_drv_data *const drv_data = (struct mcp23017_drv_data *const)dev->data;
+ uint16_t port;
+ int ret;
+
+ /* Setup pin pull up or pull down */
+ port = drv_data->reg_cache.gppu;
+
+ /* pull down == 0, pull up == 1 */
+ if ((flags & GPIO_PULL_DOWN) != 0U) {
+ return -ENOTSUP;
+ }
+
+ WRITE_BIT(port, pin, (flags & GPIO_PULL_UP) != 0U);
+
+ ret = write_port_regs(dev, REG_GPPU_PORTA, port);
+ if (ret == 0) {
+ drv_data->reg_cache.gppu = port;
+ }
+
+ return ret;
+}
+
+static int mcp23017_config(const struct device *dev, gpio_pin_t pin, gpio_flags_t flags) {
+ struct mcp23017_drv_data *const drv_data = (struct mcp23017_drv_data *const)dev->data;
+ int ret;
+
+ /* Can't do SPI bus operations from an ISR */
+ if (k_is_in_isr()) {
+ return -EWOULDBLOCK;
+ }
+
+ k_sem_take(&drv_data->lock, K_FOREVER);
+
+ if ((flags & GPIO_OPEN_DRAIN) != 0U) {
+ ret = -ENOTSUP;
+ goto done;
+ };
+
+ ret = setup_pin_dir(dev, pin, flags);
+ if (ret) {
+ LOG_ERR("MCP23017: error setting pin direction (%d)", ret);
+ goto done;
+ }
+
+ ret = setup_pin_pullupdown(dev, pin, flags);
+ if (ret) {
+ LOG_ERR("MCP23017: error setting pin pull up/down (%d)", ret);
+ goto done;
+ }
+
+done:
+ k_sem_give(&drv_data->lock);
+ return ret;
+}
+
+static int mcp23017_port_get_raw(const struct device *dev, uint32_t *value) {
+ struct mcp23017_drv_data *const drv_data = (struct mcp23017_drv_data *const)dev->data;
+ uint16_t buf;
+ int ret;
+
+ /* Can't do SPI bus operations from an ISR */
+ if (k_is_in_isr()) {
+ return -EWOULDBLOCK;
+ }
+
+ k_sem_take(&drv_data->lock, K_FOREVER);
+
+ ret = read_port_regs(dev, REG_GPIO_PORTA, &buf);
+ if (ret != 0) {
+ goto done;
+ }
+
+ *value = buf;
+
+done:
+ k_sem_give(&drv_data->lock);
+ return ret;
+}
+
+static int mcp23017_port_set_masked_raw(const struct device *dev, uint32_t mask, uint32_t value) {
+ struct mcp23017_drv_data *const drv_data = (struct mcp23017_drv_data *const)dev->data;
+ uint16_t buf;
+ int ret;
+
+ /* Can't do SPI bus operations from an ISR */
+ if (k_is_in_isr()) {
+ return -EWOULDBLOCK;
+ }
+
+ k_sem_take(&drv_data->lock, K_FOREVER);
+
+ buf = drv_data->reg_cache.gpio;
+ buf = (buf & ~mask) | (mask & value);
+
+ ret = write_port_regs(dev, REG_GPIO_PORTA, buf);
+ if (ret == 0) {
+ drv_data->reg_cache.gpio = buf;
+ }
+
+ k_sem_give(&drv_data->lock);
+
+ return ret;
+}
+
+static int mcp23017_port_set_bits_raw(const struct device *dev, uint32_t mask) {
+ return mcp23017_port_set_masked_raw(dev, mask, mask);
+}
+
+static int mcp23017_port_clear_bits_raw(const struct device *dev, uint32_t mask) {
+ return mcp23017_port_set_masked_raw(dev, mask, 0);
+}
+
+static int mcp23017_port_toggle_bits(const struct device *dev, uint32_t mask) {
+ struct mcp23017_drv_data *const drv_data = (struct mcp23017_drv_data *const)dev->data;
+ uint16_t buf;
+ int ret;
+
+ /* Can't do SPI bus operations from an ISR */
+ if (k_is_in_isr()) {
+ return -EWOULDBLOCK;
+ }
+
+ k_sem_take(&drv_data->lock, K_FOREVER);
+
+ buf = drv_data->reg_cache.gpio;
+ buf ^= mask;
+
+ ret = write_port_regs(dev, REG_GPIO_PORTA, buf);
+ if (ret == 0) {
+ drv_data->reg_cache.gpio = buf;
+ }
+
+ k_sem_give(&drv_data->lock);
+
+ return ret;
+}
+
+static int mcp23017_pin_interrupt_configure(const struct device *dev, gpio_pin_t pin,
+ enum gpio_int_mode mode, enum gpio_int_trig trig) {
+ return -ENOTSUP;
+}
+
+static const struct gpio_driver_api api_table = {
+ .pin_configure = mcp23017_config,
+ .port_get_raw = mcp23017_port_get_raw,
+ .port_set_masked_raw = mcp23017_port_set_masked_raw,
+ .port_set_bits_raw = mcp23017_port_set_bits_raw,
+ .port_clear_bits_raw = mcp23017_port_clear_bits_raw,
+ .port_toggle_bits = mcp23017_port_toggle_bits,
+ .pin_interrupt_configure = mcp23017_pin_interrupt_configure,
+};
+
+/**
+ * @brief Initialization function of MCP23017
+ *
+ * @param dev Device struct
+ * @return 0 if successful, failed otherwise.
+ */
+static int mcp23017_init(const struct device *dev) {
+ const struct mcp23017_config *const config = dev->config;
+ struct mcp23017_drv_data *const drv_data = (struct mcp23017_drv_data *const)dev->data;
+
+ drv_data->i2c = device_get_binding((char *)config->i2c_dev_name);
+ if (!drv_data->i2c) {
+ LOG_DBG("Unable to get i2c device");
+ return -ENODEV;
+ }
+
+ k_sem_init(&drv_data->lock, 1, 1);
+
+ return 0;
+}
+
+#define MCP23017_INIT(inst) \
+ static struct mcp23017_config mcp23017_##inst##_config = { \
+ .i2c_dev_name = DT_INST_BUS_LABEL(inst), \
+ .slave = DT_INST_REG_ADDR(inst), \
+ \
+ }; \
+ \
+ static struct mcp23017_drv_data mcp23017_##inst##_drvdata = { \
+ /* Default for registers according to datasheet */ \
+ .reg_cache.iodir = 0xFFFF, .reg_cache.ipol = 0x0, .reg_cache.gpinten = 0x0, \
+ .reg_cache.defval = 0x0, .reg_cache.intcon = 0x0, .reg_cache.iocon = 0x0, \
+ .reg_cache.gppu = 0x0, .reg_cache.intf = 0x0, .reg_cache.intcap = 0x0, \
+ .reg_cache.gpio = 0x0, .reg_cache.olat = 0x0, \
+ }; \
+ \
+ /* This has to init after SPI master */ \
+ DEVICE_DT_INST_DEFINE(inst, mcp23017_init, device_pm_control_nop, &mcp23017_##inst##_drvdata, \
+ &mcp23017_##inst##_config, POST_KERNEL, \
+ CONFIG_GPIO_MCP23017_INIT_PRIORITY, &api_table);
+
+DT_INST_FOREACH_STATUS_OKAY(MCP23017_INIT)
diff --git a/app/drivers/gpio/gpio_mcp23017.h b/app/drivers/gpio/gpio_mcp23017.h
new file mode 100644
index 00000000..026565cd
--- /dev/null
+++ b/app/drivers/gpio/gpio_mcp23017.h
@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) 2020 Geanix ApS, Pete Johanson
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/**
+ * @file Header file for the MCP23017 driver.
+ */
+
+#ifndef ZEPHYR_DRIVERS_GPIO_GPIO_MCP23017_H_
+#define ZEPHYR_DRIVERS_GPIO_GPIO_MCP23017_H_
+
+#include <kernel.h>
+
+#include <drivers/gpio.h>
+#include <drivers/i2c.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Register definitions */
+#define REG_IODIR_PORTA 0x00
+#define REG_IODIR_PORTB 0x01
+#define REG_IPOL_PORTA 0x02
+#define REG_IPOL_PORTB 0x03
+#define REG_GPINTEN_PORTA 0x04
+#define REG_GPINTEN_PORTB 0x05
+#define REG_DEFVAL_PORTA 0x06
+#define REG_DEFVAL_PORTB 0x07
+#define REG_INTCON_PORTA 0x08
+#define REG_INTCON_PORTB 0x09
+#define REG_GPPU_PORTA 0x0C
+#define REG_GPPU_PORTB 0x0D
+#define REG_INTF_PORTA 0x0E
+#define REG_INTF_PORTB 0x0F
+#define REG_INTCAP_PORTA 0x10
+#define REG_INTCAP_PORTB 0x11
+#define REG_GPIO_PORTA 0x12
+#define REG_GPIO_PORTB 0x13
+#define REG_OLAT_PORTA 0x14
+#define REG_OLAT_PORTB 0x15
+
+#define MCP23017_ADDR 0x40
+#define MCP23017_READBIT 0x01
+
+/** Configuration data */
+struct mcp23017_config {
+ /* gpio_driver_data needs to be first */
+ struct gpio_driver_config common;
+
+ const char *const i2c_dev_name;
+ const uint16_t slave;
+};
+
+/** Runtime driver data */
+struct mcp23017_drv_data {
+ /* gpio_driver_data needs to be first */
+ struct gpio_driver_config data;
+
+ /** Master SPI device */
+ const struct device *i2c;
+
+ struct k_sem lock;
+
+ struct {
+ uint16_t iodir;
+ uint16_t ipol;
+ uint16_t gpinten;
+ uint16_t defval;
+ uint16_t intcon;
+ uint16_t iocon;
+ uint16_t gppu;
+ uint16_t intf;
+ uint16_t intcap;
+ uint16_t gpio;
+ uint16_t olat;
+ } reg_cache;
+};
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* ZEPHYR_DRIVERS_GPIO_GPIO_MCP23017_H_ */
diff --git a/app/drivers/zephyr/dts/bindings/gpio/microchip,mcp23017.yaml b/app/drivers/zephyr/dts/bindings/gpio/microchip,mcp23017.yaml
new file mode 100644
index 00000000..75e19c49
--- /dev/null
+++ b/app/drivers/zephyr/dts/bindings/gpio/microchip,mcp23017.yaml
@@ -0,0 +1,29 @@
+#
+# Copyright (c) 2020 Geanix ApS
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+description: >
+ This is a representation of the Microchip MCP23017 I2C Gpio Expander.
+
+compatible: "microchip,mcp23017"
+
+include: [gpio-controller.yaml, i2c-device.yaml]
+
+properties:
+ label:
+ required: true
+
+ "#gpio-cells":
+ const: 2
+
+ ngpios:
+ type: int
+ required: true
+ const: 16
+ description: Number of gpios supported
+
+gpio-cells:
+ - pin
+ - flags