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Merge pull request #1431 from hathach/nrf52_i2c_1kb

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fix #1422 correct i2c max xfer len (size in bits)
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Dan Halbert 2018-12-28 10:02:13 -05:00 committed by GitHub
commit 84060e6124
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GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 30 additions and 27 deletions
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56
ports/nrf/common-hal/busio/I2C.c
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@ -37,19 +37,21 @@
#include "nrfx_spim.h"
#include "nrf_gpio.h"
// all TWI instances have the same max size
// 16 bits for 840, 10 bits for 810, 8 bits for 832
#define I2C_MAX_XFER_LEN ((1UL << TWIM0_EASYDMA_MAXCNT_SIZE) - 1)
STATIC twim_peripheral_t twim_peripherals[] = {
#if NRFX_CHECK(NRFX_TWIM0_ENABLED)
// SPIM0 and TWIM0 share an address.
{ .twim = NRFX_TWIM_INSTANCE(0),
.in_use = false,
.max_xfer_size = TWIM0_EASYDMA_MAXCNT_SIZE,
.in_use = false
},
#endif
#if NRFX_CHECK(NRFX_TWIM1_ENABLED)
// SPIM1 and TWIM1 share an address.
{ .twim = NRFX_TWIM_INSTANCE(1),
.in_use = false,
.max_xfer_size = TWIM1_EASYDMA_MAXCNT_SIZE,
.in_use = false
},
#endif
};
@ -198,24 +200,25 @@ 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 stopBit) {
if(len == 0)
if(len == 0) {
return common_hal_busio_i2c_probe(self, addr) ? 0 : MP_ENODEV;
}
const uint32_t max_xfer_size = self->twim_peripheral->max_xfer_size;
const uint32_t parts = len / max_xfer_size;
const uint32_t remainder = len % max_xfer_size;
nrfx_err_t err = NRFX_SUCCESS;
nrfx_twim_enable(&self->twim_peripheral->twim);
for (uint32_t i = 0; i < parts; ++i) {
err = nrfx_twim_tx(&self->twim_peripheral->twim, addr, data + i * max_xfer_size, max_xfer_size, !stopBit);
if (err != NRFX_SUCCESS)
break;
}
// break into MAX_XFER_LEN transaction
while ( len ) {
const size_t xact_len = MIN(len, I2C_MAX_XFER_LEN);
if ((remainder > 0) && (err == NRFX_SUCCESS))
err = nrfx_twim_tx(&self->twim_peripheral->twim, addr, data + parts * max_xfer_size, remainder, !stopBit);
if ( NRFX_SUCCESS != (err = nrfx_twim_tx(&self->twim_peripheral->twim, addr, data, xact_len, !stopBit)) ) {
break;
}
len -= xact_len;
data += xact_len;
}
nrfx_twim_disable(&self->twim_peripheral->twim);
@ -223,24 +226,25 @@ uint8_t common_hal_busio_i2c_write(busio_i2c_obj_t *self, uint16_t addr, const u
}
uint8_t common_hal_busio_i2c_read(busio_i2c_obj_t *self, uint16_t addr, uint8_t *data, size_t len) {
if(len == 0)
if(len == 0) {
return 0;
}
const uint32_t max_xfer_size = self->twim_peripheral->max_xfer_size;
const uint32_t parts = len / max_xfer_size;
const uint32_t remainder = len % max_xfer_size;
nrfx_err_t err = NRFX_SUCCESS;
nrfx_twim_enable(&self->twim_peripheral->twim);
for (uint32_t i = 0; i < parts; ++i) {
err = nrfx_twim_rx(&self->twim_peripheral->twim, addr, data + i * max_xfer_size, max_xfer_size);
if (err != NRFX_SUCCESS)
break;
}
// break into MAX_XFER_LEN transaction
while ( len ) {
const size_t xact_len = MIN(len, I2C_MAX_XFER_LEN);
if ((remainder > 0) && (err == NRFX_SUCCESS))
err = nrfx_twim_rx(&self->twim_peripheral->twim, addr, data + parts * max_xfer_size, remainder);
if ( NRFX_SUCCESS != (err = nrfx_twim_rx(&self->twim_peripheral->twim, addr, data, xact_len)) ) {
break;
}
len -= xact_len;
data += xact_len;
}
nrfx_twim_disable(&self->twim_peripheral->twim);

1
ports/nrf/common-hal/busio/I2C.h
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@ -34,7 +34,6 @@
typedef struct {
nrfx_twim_t twim;
bool in_use;
uint8_t max_xfer_size;
} twim_peripheral_t;
typedef struct {