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Add pull up testing, proper us delay and stop supporting 45 and 46 for I2C
1 parent ae52d05 commit 6f050d7

2 files changed

Lines changed: 28 additions & 47 deletions

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‎ports/esp32s2/common-hal/busio/I2C.c‎

Lines changed: 26 additions & 46 deletions
Original file line numberDiff line numberDiff line change
@@ -3,7 +3,7 @@
33
*
44
* The MIT License (MIT)
55
*
6-
* Copyright (c) 2016 Scott Shawcroft
6+
* Copyright (c) 2020 Scott Shawcroft for Adafruit Industries LLC
77
*
88
* Permission is hereby granted, free of charge, to any person obtaining a copy
99
* of this software and associated documentation files (the "Software"), to deal
@@ -30,16 +30,9 @@
3030

3131
#include "driver/i2c.h"
3232

33-
#include "esp_log.h"
34-
3533
#include "shared-bindings/microcontroller/__init__.h"
3634
#include "supervisor/shared/translate.h"
3735

38-
// Number of times to try to send packet if failed.
39-
#define ATTEMPTS 2
40-
41-
static const char* TAG = "CircuitPython I2C";
42-
4336
typedef enum {
4437
STATUS_FREE = 0,
4538
STATUS_IN_USE,
@@ -63,42 +56,43 @@ void i2c_reset(void) {
6356

6457
void common_hal_busio_i2c_construct(busio_i2c_obj_t *self,
6558
const mcu_pin_obj_t* scl, const mcu_pin_obj_t* sda, uint32_t frequency, uint32_t timeout) {
66-
67-
// Make sure scl and sda aren't input only
59+
// Pins 45 and 46 are "strapping" pins that impact start up behavior. They usually need to
60+
// be pulled-down so pulling them up for I2C is a bad idea. To make this hard, we don't
61+
// support I2C on these pins.
62+
//
63+
// 46 is also input-only so it'll never work.
64+
if (scl->number == 45 || scl->number == 46 || sda->number == 45 || sda->number == 46) {
65+
mp_raise_ValueError(translate("Invalid pins"));
66+
}
6867

6968
#if CIRCUITPY_REQUIRE_I2C_PULLUPS
70-
// // Test that the pins are in a high state. (Hopefully indicating they are pulled up.)
71-
// gpio_set_pin_function(sda->number, GPIO_PIN_FUNCTION_OFF);
72-
// gpio_set_pin_function(scl->number, GPIO_PIN_FUNCTION_OFF);
73-
// gpio_set_pin_direction(sda->number, GPIO_DIRECTION_IN);
74-
// gpio_set_pin_direction(scl->number, GPIO_DIRECTION_IN);
69+
// Test that the pins are in a high state. (Hopefully indicating they are pulled up.)
70+
gpio_set_direction(sda->number, GPIO_MODE_DEF_INPUT);
71+
gpio_set_direction(scl->number, GPIO_MODE_DEF_INPUT);
7572

76-
// gpio_set_pin_pull_mode(sda->number, GPIO_PULL_DOWN);
77-
// gpio_set_pin_pull_mode(scl->number, GPIO_PULL_DOWN);
73+
gpio_pulldown_en(sda->number);
74+
gpio_pulldown_en(scl->number);
7875

79-
// common_hal_mcu_delay_us(10);
76+
common_hal_mcu_delay_us(10);
8077

81-
// gpio_set_pin_pull_mode(sda->number, GPIO_PULL_OFF);
82-
// gpio_set_pin_pull_mode(scl->number, GPIO_PULL_OFF);
78+
gpio_pulldown_dis(sda->number);
79+
gpio_pulldown_dis(scl->number);
8380

84-
// // We must pull up within 3us to achieve 400khz.
85-
// common_hal_mcu_delay_us(3);
81+
// We must pull up within 3us to achieve 400khz.
82+
common_hal_mcu_delay_us(3);
8683

87-
// if (!gpio_get_pin_level(sda->number) || !gpio_get_pin_level(scl->number)) {
88-
// reset_pin_number(sda->number);
89-
// reset_pin_number(scl->number);
90-
// mp_raise_RuntimeError(translate("SDA or SCL needs a pull up"));
91-
// }
84+
if (gpio_get_level(sda->number) == 0 || gpio_get_level(scl->number) == 0) {
85+
reset_pin_number(sda->number);
86+
reset_pin_number(scl->number);
87+
mp_raise_RuntimeError(translate("SDA or SCL needs a pull up"));
88+
}
9289
#endif
93-
ESP_EARLY_LOGW(TAG, "create I2C");
9490

9591

9692
self->semaphore_handle = xSemaphoreCreateBinaryStatic(&self->semaphore);
9793
xSemaphoreGive(self->semaphore_handle);
98-
ESP_EARLY_LOGW(TAG, "new I2C lock %x", self->semaphore_handle);
9994
self->sda_pin = sda;
10095
self->scl_pin = scl;
101-
ESP_EARLY_LOGW(TAG, "scl %d sda %d", self->sda_pin->number, self->scl_pin->number);
10296
self->i2c_num = I2C_NUM_MAX;
10397
for (i2c_port_t num = 0; num < I2C_NUM_MAX; num++) {
10498
if (i2c_status[num] == STATUS_FREE) {
@@ -120,15 +114,10 @@ void common_hal_busio_i2c_construct(busio_i2c_obj_t *self,
120114
.clk_speed = frequency,
121115
}
122116
};
123-
// ESP_EARLY_LOGW(TAG, "param config %p %p %d %d", &i2c_conf, &(i2c_conf.mode), i2c_conf.mode, I2C_MODE_MAX);
124-
ESP_EARLY_LOGW(TAG, "param config %p %d %d", &i2c_conf, i2c_conf.mode, I2C_MODE_MAX);
125117
esp_err_t result = i2c_param_config(self->i2c_num, &i2c_conf);
126118
if (result != ESP_OK) {
127-
ESP_EARLY_LOGW(TAG, "error %d %p %d %d", result, &i2c_conf, (&i2c_conf)->mode, I2C_MODE_MAX);
128-
vTaskDelay(0);
129119
mp_raise_ValueError(translate("Invalid pins"));
130120
}
131-
ESP_EARLY_LOGW(TAG, "param config I2C done");
132121
result = i2c_driver_install(self->i2c_num,
133122
I2C_MODE_MASTER,
134123
0,
@@ -140,7 +129,6 @@ void common_hal_busio_i2c_construct(busio_i2c_obj_t *self,
140129

141130
claim_pin(sda);
142131
claim_pin(scl);
143-
ESP_EARLY_LOGW(TAG, "create I2C done");
144132
}
145133

146134
bool common_hal_busio_i2c_deinited(busio_i2c_obj_t *self) {
@@ -166,19 +154,13 @@ bool common_hal_busio_i2c_probe(busio_i2c_obj_t *self, uint8_t addr) {
166154
i2c_master_start(cmd);
167155
i2c_master_write_byte(cmd, addr << 1, true);
168156
i2c_master_stop(cmd);
169-
esp_err_t result = i2c_master_cmd_begin(self->i2c_num, cmd, 100);
157+
esp_err_t result = i2c_master_cmd_begin(self->i2c_num, cmd, 10);
170158
i2c_cmd_link_delete(cmd);
171159
return result == ESP_OK;
172160
}
173161

174162
bool common_hal_busio_i2c_try_lock(busio_i2c_obj_t *self) {
175-
ESP_EARLY_LOGW(TAG, "locking I2C %x", self->semaphore_handle);
176163
self->has_lock = xSemaphoreTake(self->semaphore_handle, 0) == pdTRUE;
177-
if (self->has_lock) {
178-
ESP_EARLY_LOGW(TAG, "lock grabbed");
179-
} else {
180-
ESP_EARLY_LOGW(TAG, "unable to grab lock");
181-
}
182164
return self->has_lock;
183165
}
184166

@@ -187,7 +169,6 @@ bool common_hal_busio_i2c_has_lock(busio_i2c_obj_t *self) {
187169
}
188170

189171
void common_hal_busio_i2c_unlock(busio_i2c_obj_t *self) {
190-
ESP_EARLY_LOGW(TAG, "unlocking I2C");
191172
xSemaphoreGive(self->semaphore_handle);
192173
self->has_lock = false;
193174
}
@@ -213,8 +194,7 @@ uint8_t common_hal_busio_i2c_write(busio_i2c_obj_t *self, uint16_t addr,
213194
}
214195

215196
uint8_t common_hal_busio_i2c_read(busio_i2c_obj_t *self, uint16_t addr,
216-
uint8_t *data, size_t len) {
217-
197+
uint8_t *data, size_t len) {
218198
i2c_cmd_handle_t cmd = i2c_cmd_link_create();
219199
i2c_master_start(cmd);
220200
i2c_master_write_byte(cmd, addr << 1 | 1, true); // | 1 to indicate read

‎ports/esp32s2/mphalport.c‎

Lines changed: 2 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -32,9 +32,10 @@
3232
#include "py/gc.h"
3333

3434
#include "esp-idf/components/xtensa/include/esp_debug_helpers.h"
35+
#include "esp-idf/components/esp_rom/include/esp32s2/rom/ets_sys.h"
3536

3637
void mp_hal_delay_us(mp_uint_t delay) {
37-
mp_hal_delay_ms(delay / 1000);
38+
ets_delay_us(delay);
3839
}
3940

4041
// This is provided by the esp-idf/components/xtensa/esp32s2/libhal.a binary

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