【添加】：实现使用micropython 的 rt-thread iic 驱动调用。

port/machine_hw_i2c.c

@@ -3,7 +3,7 @@
  *
  * The MIT License (MIT)
  *
- * Copyright (c) 2016 Damien P. George
+ * Copyright (c) 2017 SummerGift <zhangyuan@rt-thread.com>
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -31,156 +31,31 @@
 #include "py/mphal.h"
 #include "py/mperrno.h"
 #include "extmod/machine_i2c.h"
-//#include "i2c.h"
 
 #ifdef MICROPYTHON_USING_MACHINE_I2C
 
-STATIC const mp_obj_type_t machine_hard_i2c_type;
+#define I2CBUS_NAME             "i2c0"
 
-#if defined(STM32F4)
+STATIC const mp_obj_type_t machine_hard_i2c_type;
+STATIC struct rt_i2c_bus_device *i2c_bus;
 
 typedef struct _machine_hard_i2c_obj_t {
     mp_obj_base_t base;
-    const pyb_i2c_obj_t *pyb;
     uint32_t *timeout;
 } machine_hard_i2c_obj_t;
 
-STATIC uint32_t machine_hard_i2c_timeout[4];
-
-STATIC const machine_hard_i2c_obj_t machine_hard_i2c_obj[] = {
-    {{&machine_hard_i2c_type}, &pyb_i2c_obj[0], &machine_hard_i2c_timeout[0]},
-    {{&machine_hard_i2c_type}, &pyb_i2c_obj[1], &machine_hard_i2c_timeout[1]},
-    {{&machine_hard_i2c_type}, &pyb_i2c_obj[2], &machine_hard_i2c_timeout[2]},
-    {{&machine_hard_i2c_type}, &pyb_i2c_obj[3], &machine_hard_i2c_timeout[3]},
-};
+#if defined(RT_USING_I2C)
 
 STATIC void machine_hard_i2c_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
-    machine_hard_i2c_obj_t *self = MP_OBJ_TO_PTR(self_in);
-    mp_printf(print, "I2C(%u, freq=%u, timeout=%u)",
-        self - &machine_hard_i2c_obj[0] + 1,
-        i2c_get_baudrate(self->pyb->i2c),
-        *self->timeout);
-}
-
-STATIC void machine_hard_i2c_init(const machine_hard_i2c_obj_t *self, uint32_t freq, uint32_t timeout) {
-    *self->timeout = timeout;
-    i2c_init_freq(self->pyb, freq);
-}
-
-// this function is based on STM code
-STATIC bool I2C_IsAcknowledgeFailed(I2C_HandleTypeDef *hi2c) {
-    if (__HAL_I2C_GET_FLAG(hi2c, I2C_FLAG_AF) == SET) {
-        /* Clear NACKF Flag */
-        __HAL_I2C_CLEAR_FLAG(hi2c, I2C_FLAG_AF);
-        return true;
-    }
-    return false;
-}
-
-// this function is based on STM code
-STATIC bool I2C_WaitOnFlagUntilTimeout(I2C_HandleTypeDef *hi2c, uint32_t Flag, FlagStatus Status, uint32_t Timeout, uint32_t Tickstart) {
-    /* Wait until flag is set */
-    while ((__HAL_I2C_GET_FLAG(hi2c, Flag) ? SET : RESET) == Status) {
-        if (Timeout != HAL_MAX_DELAY) {
-            if ((Timeout == 0U)||((HAL_GetTick() - Tickstart ) > Timeout)) {
-                return false;
-            }
-        }
-    }
-    return true;
-}
-
-// this function is based on STM code
-STATIC int I2C_WaitOnRXNEFlagUntilTimeout(I2C_HandleTypeDef *hi2c, uint32_t Timeout, uint32_t Tickstart) {
-    while (__HAL_I2C_GET_FLAG(hi2c, I2C_FLAG_RXNE) == RESET) {
-        /* Check if a STOPF is detected */
-        if (__HAL_I2C_GET_FLAG(hi2c, I2C_FLAG_STOPF) == SET) {
-            /* Clear STOP Flag */
-            __HAL_I2C_CLEAR_FLAG(hi2c, I2C_FLAG_STOPF);
-            return -MP_EBUSY;
-        }
-
-        /* Check for the Timeout */
-        if ((Timeout == 0U) || ((HAL_GetTick()-Tickstart) > Timeout)) {
-            return -MP_ETIMEDOUT;
-        }
-    }
-    return 0;
+    return;
 }
 
-// this function is based on STM code
-STATIC int send_addr_byte(I2C_HandleTypeDef *hi2c, uint8_t addr_byte, uint32_t Timeout, uint32_t Tickstart) {
-    /* Generate Start */
-    hi2c->Instance->CR1 |= I2C_CR1_START;
-
-    /* Wait until SB flag is set */
-    if (!I2C_WaitOnFlagUntilTimeout(hi2c, I2C_FLAG_SB, RESET, Timeout, Tickstart)) {
-        return -MP_ETIMEDOUT;
-    }
-
-    /* Send slave address */
-    hi2c->Instance->DR = addr_byte;
-
-    /* Wait until ADDR flag is set */
-    while (__HAL_I2C_GET_FLAG(hi2c, I2C_FLAG_ADDR) == RESET) {
-        if (__HAL_I2C_GET_FLAG(hi2c, I2C_FLAG_AF) == SET) {
-            // nack received for addr, release the bus cleanly
-            hi2c->Instance->CR1 |= I2C_CR1_STOP;
-            __HAL_I2C_CLEAR_FLAG(hi2c, I2C_FLAG_AF);
-            return -MP_ENODEV;
-        }
-
-        /* Check for the Timeout */
-        if (Timeout != HAL_MAX_DELAY) {
-            if ((Timeout == 0U)||((HAL_GetTick() - Tickstart ) > Timeout)) {
-                return -MP_ETIMEDOUT;
-            }
-        }
-    }
-
-    return 0;
-}
-
-// this function is based on STM code
 int machine_hard_i2c_readfrom(mp_obj_base_t *self_in, uint16_t addr, uint8_t *dest, size_t len, bool stop) {
-    machine_hard_i2c_obj_t *self = (machine_hard_i2c_obj_t*)self_in;
-
-#if 0
-    // TODO: for multi-master, here we could wait for the bus to be free
-    // we'd need a flag to tell if we were in the middle of a set of transactions
-    // (ie didn't send a stop bit in the last call)
-    /* Wait until BUSY flag is reset */
-    if (!I2C_WaitOnFlagUntilTimeout(hi2c, I2C_FLAG_BUSY, SET, I2C_TIMEOUT_BUSY_FLAG, tickstart)) {
-        return -MP_EBUSY;
-    }
-#endif
-
-
-    return 0;
+    return rt_i2c_master_recv(i2c_bus, addr, 0, dest, len);
 }
 
-// this function is based on STM code
 int machine_hard_i2c_writeto(mp_obj_base_t *self_in, uint16_t addr, const uint8_t *src, size_t len, bool stop) {
-    machine_hard_i2c_obj_t *self = (machine_hard_i2c_obj_t*)self_in;
-    I2C_HandleTypeDef *hi2c = self->pyb->i2c;
-    uint32_t Timeout = *self->timeout;
-
-#if 0
-    // TODO: for multi-master, here we could wait for the bus to be free
-    // we'd need a flag to tell if we were in the middle of a set of transactions
-    // (ie didn't send a stop bit in the last call)
-    /* Wait until BUSY flag is reset */
-    if (!I2C_WaitOnFlagUntilTimeout(hi2c, I2C_FLAG_BUSY, SET, I2C_TIMEOUT_BUSY_FLAG, tickstart)) {
-        return -MP_EBUSY;
-    }
-#endif
-
-    return num_acks;
-
-timeout:
-    // timeout, release the bus cleanly
-    hi2c->Instance->CR1 |= I2C_CR1_STOP;
-    return -MP_ETIMEDOUT;
+    return rt_i2c_master_send(i2c_bus, addr, 0, src, len);
 }
 
 #endif
@@ -189,63 +64,28 @@ timeout:
 /* MicroPython bindings for machine API                                       */
 
 mp_obj_t machine_hard_i2c_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) {
-    // parse args
-    enum { ARG_id, ARG_scl, ARG_sda, ARG_freq, ARG_timeout };
-    static const mp_arg_t allowed_args[] = {
-        { MP_QSTR_id, MP_ARG_REQUIRED | MP_ARG_OBJ },
-        { MP_QSTR_scl, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
-        { MP_QSTR_sda, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
-        { MP_QSTR_freq, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 400000} },
-        { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 1000} },
-    };
-    mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
-    mp_arg_parse_all_kw_array(n_args, n_kw, all_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
+    char iic_device[10];
+    snprintf(iic_device, 10, "i2c%d", mp_obj_get_int(all_args[0]));
+    i2c_bus = rt_i2c_bus_device_find(iic_device);
 
-    // work out i2c bus
-    int i2c_id = 0;
-    if (MP_OBJ_IS_STR(args[ARG_id].u_obj)) {
-        const char *port = mp_obj_str_get_str(args[ARG_id].u_obj);
-        if (0) {
-        #ifdef MICROPY_HW_I2C1_NAME
-        } else if (strcmp(port, MICROPY_HW_I2C1_NAME) == 0) {
-            i2c_id = 1;
-        #endif
-        #ifdef MICROPY_HW_I2C2_NAME
-        } else if (strcmp(port, MICROPY_HW_I2C2_NAME) == 0) {
-            i2c_id = 2;
-        #endif
-        #ifdef MICROPY_HW_I2C3_NAME
-        } else if (strcmp(port, MICROPY_HW_I2C3_NAME) == 0) {
-            i2c_id = 3;
-        #endif
-        } else {
-            nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError,
-                "I2C(%s) doesn't exist", port));
-        }
+    if (i2c_bus == RT_NULL) {
+        rt_kprintf("can't find %s device\r\n", iic_device);
+        nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "I2C(%s) doesn't exist", iic_device));
     } else {
-        i2c_id = mp_obj_get_int(args[ARG_id].u_obj);
-        if (i2c_id < 1 || i2c_id > MP_ARRAY_SIZE(machine_hard_i2c_obj)
-            || machine_hard_i2c_obj[i2c_id - 1].base.type == NULL) {
-            nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError,
-                "I2C(%d) doesn't exist", i2c_id));
-        }
+        rt_kprintf("find %s device\r\n", iic_device);
     }
 
-    // get static peripheral object
-    machine_hard_i2c_obj_t *self = (machine_hard_i2c_obj_t*)&machine_hard_i2c_obj[i2c_id - 1];
-
-    // here we would check the scl/sda pins and configure them, but it's not implemented
-    if (args[ARG_scl].u_obj != MP_OBJ_NULL || args[ARG_sda].u_obj != MP_OBJ_NULL) {
-        mp_raise_ValueError("explicit choice of scl/sda is not implemented");
-    }
-
-    // initialise the I2C peripheral
-    machine_hard_i2c_init(self, args[ARG_freq].u_int, args[ARG_timeout].u_int);
-
-    return MP_OBJ_FROM_PTR(self);
+    // create new hard I2C object
+    machine_hard_i2c_obj_t *self = m_new_obj(machine_hard_i2c_obj_t);
+    self->base.type = &machine_hard_i2c_type;
+    return (mp_obj_t) self;
 }
 
 STATIC const mp_machine_i2c_p_t machine_hard_i2c_p = {
+    .start = NULL,
+    .stop = NULL,
+    .read = NULL,
+    .write = NULL,
     .readfrom = machine_hard_i2c_readfrom,
     .writeto = machine_hard_i2c_writeto,
 };