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Initial fix, but bitbangio timing may be off

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This commit is contained in:
Dan Halbert 2021-02-18 13:14:51 -05:00
parent 261b077209
commit 53a002a096
2 changed files with 34 additions and 4 deletions
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34
ports/raspberrypi/common-hal/busio/I2C.c
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@ -24,12 +24,12 @@
* THE SOFTWARE.
*/
#include "py/mphal.h"
#include "shared-bindings/busio/I2C.h"
#include "py/mperrno.h"
#include "py/runtime.h"
#include "shared-bindings/microcontroller/__init__.h"
#include "supervisor/shared/translate.h"
#include "shared-bindings/bitbangio/I2C.h"
#include "src/rp2_common/hardware_gpio/include/hardware/gpio.h"
@ -99,6 +99,12 @@ void common_hal_busio_i2c_construct(busio_i2c_obj_t *self,
self->baudrate = i2c_init(self->peripheral, frequency);
// Remember these in case we need to use bitbangio to do short writes.
self->sda = sda;
self->scl = scl;
self->frequency = frequency;
self->timeout = timeout;
self->sda_pin = sda->number;
self->scl_pin = scl->number;
claim_pin(sda);
@ -124,8 +130,7 @@ void common_hal_busio_i2c_deinit(busio_i2c_obj_t *self) {
}
bool common_hal_busio_i2c_probe(busio_i2c_obj_t *self, uint8_t addr) {
uint8_t fake_read = 0;
return i2c_read_blocking(self->peripheral, addr, &fake_read, 1, false) != PICO_ERROR_GENERIC;
return common_hal_busio_i2c_write(self, addr, NULL, 0, false) == 0;
}
bool common_hal_busio_i2c_try_lock(busio_i2c_obj_t *self) {
@ -147,6 +152,27 @@ void common_hal_busio_i2c_unlock(busio_i2c_obj_t *self) {
uint8_t common_hal_busio_i2c_write(busio_i2c_obj_t *self, uint16_t addr,
const uint8_t *data, size_t len, bool transmit_stop_bit) {
if (len <= 2) {
// Give up pin ownership temporarily and use a bitbangio.I2C to do the write.
reset_pin_number(self->sda_pin);
reset_pin_number(self->scl_pin);
bitbangio_i2c_obj_t bitbangio_i2c;
shared_module_bitbangio_i2c_construct(&bitbangio_i2c, self->sda, self->scl,
self->frequency, self->timeout);
uint8_t status = shared_module_bitbangio_i2c_write(&bitbangio_i2c, addr, data, len, transmit_stop_bit);
shared_module_bitbangio_i2c_deinit(&bitbangio_i2c);
// Take back the pins and restore them to hardware I2C functionality.
claim_pin(self->sda);
claim_pin(self->scl);
gpio_set_function(self->sda_pin, GPIO_FUNC_I2C);
gpio_set_function(self->scl_pin, GPIO_FUNC_I2C);
return status;
}
int result = i2c_write_blocking(self->peripheral, addr, data, len, !transmit_stop_bit);
if (result == len) {
return 0;

4
ports/raspberrypi/common-hal/busio/I2C.h
View File

@ -36,6 +36,10 @@
typedef struct {
mp_obj_base_t base;
i2c_inst_t * peripheral;
const mcu_pin_obj_t *scl;
const mcu_pin_obj_t *sda;
uint32_t frequency;
uint32_t timeout;
bool has_lock;
uint baudrate;
uint8_t scl_pin;