esp32[c3|c6|h2]: Add I2C bitbang supoort

arch/risc-v/src/common/espressif/Kconfig

@@ -320,11 +320,17 @@ config ESPRESSIF_I2C
 	bool
 	default n
 
+config ESPRESSIF_I2C_PERIPH
+	bool
+	depends on (ESPRESSIF_I2C0 || ESPRESSIF_I2C1)
+	default n
+
 config ESPRESSIF_I2C0
 	bool "I2C 0"
 	default n
 	select ESPRESSIF_I2C
 	select I2C
+	select ESPRESSIF_I2C_PERIPH
 
 config ESPRESSIF_I2C1
 	bool "I2C 1"
@@ -332,6 +338,17 @@ config ESPRESSIF_I2C1
 	depends on ARCH_CHIP_ESP32H2
 	select ESPRESSIF_I2C
 	select I2C
+	select ESPRESSIF_I2C_PERIPH
+
+config ESPRESSIF_I2C_BITBANG
+	bool "I2C Bitbang"
+	default n
+	select I2C_BITBANG
+	select ESPRESSIF_I2C
+	select I2C
+	select I2C_BITBANG
+	---help---
+		Software implemented I2C peripheral with GPIOs. Suggested to use if I2C peripherals are already in use.
 
 config ESPRESSIF_SPI
 	bool
@@ -1574,12 +1591,28 @@ config ESPRESSIF_I2C1_SDAPIN
 
 endif # ESPRESSIF_I2C1
 
+if ESPRESSIF_I2C_BITBANG
+
+config ESPRESSIF_I2C_BITBANG_SCLPIN
+	int "I2C Bitbang SCL Pin"
+	default 0
+	range 0 21
+
+config ESPRESSIF_I2C_BITBANG_SDAPIN
+	int "I2C Bitbang SDA Pin"
+	default 1
+	range 0 21
+
+endif # ESPRESSIF_I2C_BITBANG
+
 config ESPRESSIF_I2CTIMEOSEC
 	int "Timeout seconds"
+	depends on ESPRESSIF_I2C_PERIPH
 	default 0
 
 config ESPRESSIF_I2CTIMEOMS
 	int "Timeout milliseconds"
+	depends on ESPRESSIF_I2C_PERIPH
 	default 500
 
 endmenu # I2C configuration

arch/risc-v/src/common/espressif/Make.defs

@@ -99,7 +99,12 @@ ifeq ($(CONFIG_ESPRESSIF_TEMP),y)
 endif
 
 ifeq ($(CONFIG_ESPRESSIF_I2C),y)
-	CHIP_CSRCS += esp_i2c.c
+	ifeq ($(CONFIG_ESPRESSIF_I2C_PERIPH),y)
+		CHIP_CSRCS += esp_i2c.c
+	endif
+	ifeq ($(CONFIG_ESPRESSIF_I2C_BITBANG),y)
+		CHIP_CSRCS += esp_i2c_bitbang.c
+	endif
 endif
 
 ifeq ($(CONFIG_ESPRESSIF_SPI),y)

arch/risc-v/src/common/espressif/esp_i2c.c

@@ -24,7 +24,7 @@
 
 #include <nuttx/config.h>
 
-#ifdef CONFIG_ESPRESSIF_I2C
+#ifdef CONFIG_ESPRESSIF_I2C_PERIPH
 
 #include <sys/types.h>
 #include <stdio.h>
@@ -1604,4 +1604,4 @@ int esp_i2cbus_uninitialize(struct i2c_master_s *dev)
   return OK;
 }
 
-#endif /* CONFIG_ESPRESSIF_I2C */
+#endif /* CONFIG_ESPRESSIF_I2C_PERIPH */

arch/risc-v/src/common/espressif/esp_i2c.h

@@ -51,6 +51,7 @@
  * Public Function Prototypes
  ****************************************************************************/
 
+#ifdef CONFIG_ESPRESSIF_I2C_PERIPH
 /****************************************************************************
  * Name: esp_i2cbus_initialize
  *
@@ -86,6 +87,7 @@ struct i2c_master_s *esp_i2cbus_initialize(int port);
  ****************************************************************************/
 
 int esp_i2cbus_uninitialize(struct i2c_master_s *dev);
+#endif /* CONFIG_ESPRESSIF_I2C_PERIPH */
 
 #endif /* __ASSEMBLY__ */
 #endif /* __ARCH_RISCV_SRC_COMMON_ESPRESSIF_ESP_I2C_H */

arch/risc-v/src/common/espressif/esp_i2c_bitbang.c

@@ -0,0 +1,247 @@
+/****************************************************************************
+ * arch/risc-v/src/common/espressif/esp_i2c_bitbang.c
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#ifdef CONFIG_ESPRESSIF_I2C_BITBANG
+#include <assert.h>
+#include <nuttx/i2c/i2c_master.h>
+#include <nuttx/i2c/i2c_bitbang.h>
+#include <nuttx/kmalloc.h>
+
+#include "espressif/esp_i2c_bitbang.h"
+#include "soc/gpio_sig_map.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+struct esp_i2c_bitbang_dev_s
+{
+  struct i2c_bitbang_lower_dev_s lower;
+  int sda_pin;
+  int scl_pin;
+};
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+static void esp_i2c_bitbang_init(struct i2c_bitbang_lower_dev_s *lower);
+static void esp_i2c_bitbang_set_scl(struct i2c_bitbang_lower_dev_s *lower,
+                                    bool value);
+static void esp_i2c_bitbang_set_sda(struct i2c_bitbang_lower_dev_s *lower,
+                                    bool value);
+static bool esp_i2c_bitbang_get_scl(struct i2c_bitbang_lower_dev_s *lower);
+static bool esp_i2c_bitbang_get_sda(struct i2c_bitbang_lower_dev_s *lower);
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/* Lower-half I2C bitbang data  */
+
+const static struct i2c_bitbang_lower_ops_s g_ops =
+{
+  .initialize = esp_i2c_bitbang_init,
+  .set_scl    = esp_i2c_bitbang_set_scl,
+  .set_sda    = esp_i2c_bitbang_set_sda,
+  .get_scl    = esp_i2c_bitbang_get_scl,
+  .get_sda    = esp_i2c_bitbang_get_sda
+};
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: esp_i2c_bitbang_init
+ *
+ * Description:
+ *   Initialize the I2C bit-bang driver
+ *
+ * Input Parameters:
+ *   lower - A pointer the publicly visible representation of
+ *           the "lower-half" driver state structure.
+ *
+ * Returned Value:
+ *   None
+ *
+ ****************************************************************************/
+
+static void esp_i2c_bitbang_init(struct i2c_bitbang_lower_dev_s *lower)
+{
+  struct esp_i2c_bitbang_dev_s *dev = lower->priv;
+
+  esp_gpiowrite(dev->scl_pin, 1);
+  esp_gpiowrite(dev->sda_pin, 1);
+
+  esp_configgpio(dev->scl_pin, INPUT_PULLUP | OUTPUT_OPEN_DRAIN);
+  esp_gpio_matrix_out(dev->scl_pin, SIG_GPIO_OUT_IDX, 0, 0);
+
+  esp_configgpio(dev->sda_pin, INPUT_PULLUP | OUTPUT_OPEN_DRAIN);
+  esp_gpio_matrix_out(dev->sda_pin, SIG_GPIO_OUT_IDX, 0, 0);
+}
+
+/****************************************************************************
+ * Name: esp_i2c_bitbang_set_scl
+ *
+ * Description:
+ *   Set SCL line value
+ *
+ * Input Parameters:
+ *   lower - A pointer the publicly visible representation of
+ *           the "lower-half" driver state structure.
+ *   value - The value to be written (0 or 1).
+ *
+ * Returned Value:
+ *   None
+ *
+ ****************************************************************************/
+
+static void esp_i2c_bitbang_set_scl(struct i2c_bitbang_lower_dev_s *lower,
+                                    bool value)
+{
+  struct esp_i2c_bitbang_dev_s *dev =
+    (struct esp_i2c_bitbang_dev_s *)lower->priv;
+
+  esp_gpiowrite(dev->scl_pin, value);
+}
+
+/****************************************************************************
+ * Name: esp_i2c_bitbang_set_sda
+ *
+ * Description:
+ *   Set SDA line value
+ *
+ * Input Parameters:
+ *   lower - A pointer the publicly visible representation of
+ *           the "lower-half" driver state structure.
+ *   value - The value to be written (0 or 1).
+ *
+ * Returned Value:
+ *   None
+ *
+ ****************************************************************************/
+
+static void esp_i2c_bitbang_set_sda(struct i2c_bitbang_lower_dev_s *lower,
+                                    bool value)
+{
+  struct esp_i2c_bitbang_dev_s *dev =
+    (struct esp_i2c_bitbang_dev_s *)lower->priv;
+
+  esp_gpiowrite(dev->sda_pin, value);
+}
+
+/****************************************************************************
+ * Name: esp_i2c_bitbang_get_scl
+ *
+ * Description:
+ *   Get value from SCL line
+ *
+ * Input Parameters:
+ *   lower - A pointer the publicly visible representation of
+ *           the "lower-half" driver state structure.
+ *
+ * Returned Value:
+ *   The boolean representation of the SCL line value (true/false).
+ *
+ ****************************************************************************/
+
+static bool esp_i2c_bitbang_get_scl(struct i2c_bitbang_lower_dev_s *lower)
+{
+  struct esp_i2c_bitbang_dev_s *dev =
+    (struct esp_i2c_bitbang_dev_s *)lower->priv;
+
+  return esp_gpioread(dev->scl_pin);
+}
+
+/****************************************************************************
+ * Name: esp_i2c_bitbang_get_sda
+ *
+ * Description:
+ *   Get value from SDA line
+ *
+ * Input Parameters:
+ *   lower - A pointer the publicly visible representation of
+ *           the "lower-half" driver state structure.
+ *
+ * Returned Value:
+ *   The boolean representation of the SDA line value (true/false).
+ *
+ ****************************************************************************/
+
+static bool esp_i2c_bitbang_get_sda(struct i2c_bitbang_lower_dev_s *lower)
+{
+  struct esp_i2c_bitbang_dev_s *dev =
+    (struct esp_i2c_bitbang_dev_s *)lower->priv;
+
+  return esp_gpioread(dev->sda_pin);
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: esp_i2cbus_bitbang_initialize
+ *
+ * Description:
+ *   Initialize the I2C bitbang driver. And return a unique instance of
+ *   struct struct i2c_master_s. This function may be called to obtain
+ *   multiple instances of the interface, each of which may be set up with
+ *   a different frequency and slave address.
+ *
+ * Input Parameters:
+ *   None
+ *
+ * Returned Value:
+ *   Valid I2C device structure reference on success; a NULL on failure
+ *
+ ****************************************************************************/
+
+struct i2c_master_s *esp_i2cbus_bitbang_initialize(void)
+{
+  struct esp_i2c_bitbang_dev_s *dev =
+      (struct esp_i2c_bitbang_dev_s *)
+          kmm_malloc(sizeof(struct esp_i2c_bitbang_dev_s));
+
+  DEBUGASSERT(dev);
+
+  dev->lower.ops = &g_ops;
+  dev->lower.priv = dev;
+  dev->scl_pin = CONFIG_ESPRESSIF_I2C_BITBANG_SCLPIN;
+  dev->sda_pin = CONFIG_ESPRESSIF_I2C_BITBANG_SDAPIN;
+
+  return i2c_bitbang_initialize(&dev->lower);
+}
+#endif /* CONFIG_ESPRESSIF_I2C_BITBANG */

arch/risc-v/src/common/espressif/esp_i2c_bitbang.h

@@ -0,0 +1,90 @@
+/****************************************************************************
+ * arch/risc-v/src/common/espressif/esp_i2c_bitbang.h
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+#ifndef __ARCH_RISCV_SRC_COMMON_ESPRESSIF_ESP_I2C_BITBANG_H
+#define __ARCH_RISCV_SRC_COMMON_ESPRESSIF_ESP_I2C_BITBANG_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <nuttx/i2c/i2c_master.h>
+#include "espressif/esp_gpio.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+#ifdef CONFIG_ESPRESSIF_I2C_BITBANG
+#  define ESPRESSIF_I2C_BITBANG 3
+#endif
+
+/****************************************************************************
+ * Public Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+#ifdef __cplusplus
+#define EXTERN extern "C"
+extern "C"
+{
+#else
+#define EXTERN extern
+#endif
+
+/****************************************************************************
+ * Inline Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+#ifdef CONFIG_ESPRESSIF_I2C_BITBANG
+/****************************************************************************
+ * Name: esp_i2cbus_bitbang_initialize
+ *
+ * Description:
+ *   Initialize the I2C bitbang driver. And return a unique instance of
+ *   struct struct i2c_master_s. This function may be called to obtain
+ *   multiple instances of the interface, each of which may be set up with
+ *   a different frequency and slave address.
+ *
+ * Input Parameters:
+ *   None
+ *
+ * Returned Value:
+ *   Valid I2C device structure reference on success; a NULL on failure
+ *
+ ****************************************************************************/
+
+struct i2c_master_s *esp_i2cbus_bitbang_initialize(void);
+#endif
+
+#undef EXTERN
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __ARCH_RISCV_SRC_COMMON_ESPRESSIF_ESP_I2C_BITBANG_H */

boards/risc-v/esp32c3/common/src/esp_board_bmp180.c

@@ -31,7 +31,11 @@
 #include <nuttx/sensors/bmp180.h>
 #include <nuttx/i2c/i2c_master.h>
 
+#ifndef CONFIG_ESPRESSIF_I2C_BITBANG
 #include "espressif/esp_i2c.h"
+#else
+#include "espressif/esp_i2c_bitbang.h"
+#endif
 
 #include "esp_board_bmp180.h"
 
@@ -64,7 +68,11 @@ int board_bmp180_initialize(int devno)
 
   /* Initialize BMP180 */
 
+#ifndef CONFIG_ESPRESSIF_I2C_BITBANG
   i2c = esp_i2cbus_initialize(ESPRESSIF_I2C0);
+#else
+  i2c = esp_i2cbus_bitbang_initialize();
+#endif
 
   if (i2c)
     {

boards/risc-v/esp32c3/common/src/esp_board_i2c.c

@@ -30,12 +30,41 @@
 
 #include <nuttx/i2c/i2c_master.h>
 
+#ifdef CONFIG_ESPRESSIF_I2C_BITBANG
+#include "espressif/esp_i2c_bitbang.h"
+#endif
+#ifdef CONFIG_ESPRESSIF_I2C_PERIPH
 #include "espressif/esp_i2c.h"
+#endif
 
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
 
+#ifdef CONFIG_ESPRESSIF_I2C_BITBANG
+static int i2c_bitbang_driver_init(int bus)
+{
+  struct i2c_master_s *i2c;
+  int ret;
+
+  i2c = esp_i2cbus_bitbang_initialize();
+  if (i2c == NULL)
+    {
+      i2cerr("Failed to get I2C%d interface\n", bus);
+      return -ENODEV;
+    }
+
+  ret = i2c_register(i2c, bus);
+  if (ret < 0)
+    {
+      i2cerr("Failed to register I2C%d driver: %d\n", bus, ret);
+    }
+
+  return ret;
+}
+#endif
+
+#ifdef CONFIG_ESPRESSIF_I2C_PERIPH
 static int i2c_driver_init(int bus)
 {
   struct i2c_master_s *i2c;
@@ -57,6 +86,7 @@ static int i2c_driver_init(int bus)
 
   return ret;
 }
+#endif
 
 /****************************************************************************
  * Name: board_i2c_init
@@ -78,5 +108,9 @@ int board_i2c_init(void)
   ret = i2c_driver_init(ESPRESSIF_I2C0);
 #endif
 
+#ifdef CONFIG_ESPRESSIF_I2C_BITBANG
+  ret = i2c_bitbang_driver_init(ESPRESSIF_I2C_BITBANG);
+#endif
+
   return ret;
 }

boards/risc-v/esp32c6/common/src/esp_board_bmp180.c

@@ -31,7 +31,11 @@
 #include <nuttx/sensors/bmp180.h>
 #include <nuttx/i2c/i2c_master.h>
 
+#ifndef CONFIG_ESPRESSIF_I2C_BITBANG
 #include "espressif/esp_i2c.h"
+#else
+#include "espressif/esp_i2c_bitbang.h"
+#endif
 
 #include "esp_board_bmp180.h"
 
@@ -64,7 +68,11 @@ int board_bmp180_initialize(int devno)
 
   /* Initialize BMP180 */
 
+#ifndef CONFIG_ESPRESSIF_I2C_BITBANG
   i2c = esp_i2cbus_initialize(ESPRESSIF_I2C0);
+#else
+  i2c = esp_i2cbus_bitbang_initialize();
+#endif
 
   if (i2c)
     {

boards/risc-v/esp32c6/common/src/esp_board_i2c.c

@@ -30,12 +30,41 @@
 
 #include <nuttx/i2c/i2c_master.h>
 
+#ifdef CONFIG_ESPRESSIF_I2C_BITBANG
+#include "espressif/esp_i2c_bitbang.h"
+#endif
+#ifdef CONFIG_ESPRESSIF_I2C_PERIPH
 #include "espressif/esp_i2c.h"
+#endif
 
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
 
+#ifdef CONFIG_ESPRESSIF_I2C_BITBANG
+static int i2c_bitbang_driver_init(int bus)
+{
+  struct i2c_master_s *i2c;
+  int ret;
+
+  i2c = esp_i2cbus_bitbang_initialize();
+  if (i2c == NULL)
+    {
+      i2cerr("Failed to get I2C%d interface\n", bus);
+      return -ENODEV;
+    }
+
+  ret = i2c_register(i2c, bus);
+  if (ret < 0)
+    {
+      i2cerr("Failed to register I2C%d driver: %d\n", bus, ret);
+    }
+
+  return ret;
+}
+#endif
+
+#ifdef CONFIG_ESPRESSIF_I2C_PERIPH
 static int i2c_driver_init(int bus)
 {
   struct i2c_master_s *i2c;
@@ -57,6 +86,7 @@ static int i2c_driver_init(int bus)
 
   return ret;
 }
+#endif
 
 /****************************************************************************
  * Name: board_i2c_init
@@ -78,5 +108,9 @@ int board_i2c_init(void)
   ret = i2c_driver_init(ESPRESSIF_I2C0);
 #endif
 
+#ifdef CONFIG_ESPRESSIF_I2C_BITBANG
+  ret = i2c_bitbang_driver_init(ESPRESSIF_I2C_BITBANG);
+#endif
+
   return ret;
 }

boards/risc-v/esp32h2/common/src/esp_board_bmp180.c

@@ -31,7 +31,11 @@
 #include <nuttx/sensors/bmp180.h>
 #include <nuttx/i2c/i2c_master.h>
 
+#ifndef CONFIG_ESPRESSIF_I2C_BITBANG
 #include "espressif/esp_i2c.h"
+#else
+#include "espressif/esp_i2c_bitbang.h"
+#endif
 
 #include "esp_board_bmp180.h"
 
@@ -63,7 +67,11 @@ int board_bmp180_initialize(int devno)
 
   /* Initialize BMP180 */
 
+#ifndef CONFIG_ESPRESSIF_I2C_BITBANG
   i2c = esp_i2cbus_initialize(ESPRESSIF_I2C0);
+#else
+  i2c = esp_i2cbus_bitbang_initialize();
+#endif
 
   if (i2c)
     {

boards/risc-v/esp32h2/common/src/esp_board_i2c.c

@@ -30,12 +30,41 @@
 
 #include <nuttx/i2c/i2c_master.h>
 
+#ifdef CONFIG_ESPRESSIF_I2C_BITBANG
+#include "espressif/esp_i2c_bitbang.h"
+#endif
+#ifdef CONFIG_ESPRESSIF_I2C_PERIPH
 #include "espressif/esp_i2c.h"
+#endif
 
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
 
+#ifdef CONFIG_ESPRESSIF_I2C_BITBANG
+static int i2c_bitbang_driver_init(int bus)
+{
+  struct i2c_master_s *i2c;
+  int ret;
+
+  i2c = esp_i2cbus_bitbang_initialize();
+  if (i2c == NULL)
+    {
+      i2cerr("Failed to get I2C%d interface\n", bus);
+      return -ENODEV;
+    }
+
+  ret = i2c_register(i2c, bus);
+  if (ret < 0)
+    {
+      i2cerr("Failed to register I2C%d driver: %d\n", bus, ret);
+    }
+
+  return ret;
+}
+#endif
+
+#ifdef CONFIG_ESPRESSIF_I2C_PERIPH
 static int i2c_driver_init(int bus)
 {
   struct i2c_master_s *i2c;
@@ -57,6 +86,7 @@ static int i2c_driver_init(int bus)
 
   return ret;
 }
+#endif
 
 /****************************************************************************
  * Name: board_i2c_init
@@ -86,5 +116,9 @@ int board_i2c_init(void)
   ret = i2c_driver_init(ESPRESSIF_I2C1);
 #endif
 
+#ifdef CONFIG_ESPRESSIF_I2C_BITBANG
+  ret = i2c_bitbang_driver_init(ESPRESSIF_I2C_BITBANG);
+#endif
+
   return ret;
 }