diff options
| author | Damien George <damien@micropython.org> | 2022-01-21 14:52:03 +1100 |
|---|---|---|
| committer | Damien George <damien@micropython.org> | 2022-01-21 15:10:29 +1100 |
| commit | a707fe50b085ec83722106609f6fd219faf9f030 (patch) | |
| tree | aea7211b4fce20e5f3d1f9f523715461fcb9c632 | |
| parent | bef26d4e3fee7f00758d6e3ae7aa187b80d7878c (diff) | |
rp2/machine_i2c: Use soft I2C only for len=0, and increase timeout.
The RP2040 I2C hardware can do writes of length 1 and 2, just not of length
0. So only use software I2C for writes of length 0, to improve
performance.
Also increase the software I2C timeout for zero-length writes to
accommodate the behaviour of a wider range of I2C devices.
Fixes issue #8167.
Signed-off-by: Damien George <damien@micropython.org>
| -rw-r--r-- | ports/rp2/machine_i2c.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/ports/rp2/machine_i2c.c b/ports/rp2/machine_i2c.c index 56f012a5e..f785ad7de 100644 --- a/ports/rp2/machine_i2c.c +++ b/ports/rp2/machine_i2c.c @@ -127,12 +127,12 @@ STATIC int machine_i2c_transfer_single(mp_obj_base_t *self_in, uint16_t addr, si if (flags & MP_MACHINE_I2C_FLAG_READ) { ret = i2c_read_blocking(self->i2c_inst, addr, buf, len, nostop); } else { - if (len <= 2) { - // Workaround issue with hardware I2C not accepting short writes. + if (len == 0) { + // Workaround issue with hardware I2C not accepting zero-length writes. mp_machine_soft_i2c_obj_t soft_i2c = { .base = { &mp_machine_soft_i2c_type }, .us_delay = 500000 / self->freq + 1, - .us_timeout = 255, + .us_timeout = 50000, .scl = self->scl, .sda = self->sda, }; |