diff options
| author | Radomir Dopieralski <openstack@sheep.art.pl> | 2016-10-22 22:44:19 +0200 |
|---|---|---|
| committer | Damien George <damien.p.george@gmail.com> | 2016-11-17 12:43:12 +1100 |
| commit | 702928915c49c2f7af7a5de289a05c646518900b (patch) | |
| tree | c5a0e741c32da965311586efcb090fc11f5a601e /extmod/machine_i2c.c | |
| parent | b188d6e9db1842f9f66976ef1d67746239c8006c (diff) | |
extmod/machine_i2c: Make the clock stretching timeout configurable
Diffstat (limited to 'extmod/machine_i2c.c')
| -rw-r--r-- | extmod/machine_i2c.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/extmod/machine_i2c.c b/extmod/machine_i2c.c index e201b2399..5b5a0ece5 100644 --- a/extmod/machine_i2c.c +++ b/extmod/machine_i2c.c @@ -34,12 +34,10 @@ #if MICROPY_PY_MACHINE_I2C -// Clock stretching limit, so that we don't get stuck. -#define I2C_STRETCH_LIMIT 255 - typedef struct _machine_i2c_obj_t { mp_obj_base_t base; uint32_t us_delay; + uint32_t us_timeout; mp_hal_pin_obj_t scl; mp_hal_pin_obj_t sda; } machine_i2c_obj_t; @@ -58,7 +56,7 @@ STATIC void mp_hal_i2c_scl_release(machine_i2c_obj_t *self) { mp_hal_pin_od_high(self->scl); mp_hal_i2c_delay(self); // For clock stretching, wait for the SCL pin to be released, with timeout. - for (int count = I2C_STRETCH_LIMIT; mp_hal_pin_read(self->scl) == 0 && count; --count) { + for (uint32_t count = self->us_timeout; mp_hal_pin_read(self->scl) == 0 && count; --count) { mp_hal_delay_us_fast(1); } } @@ -237,16 +235,18 @@ STATIC void mp_hal_i2c_read(machine_i2c_obj_t *self, uint8_t addr, uint8_t *dest // MicroPython bindings for I2C STATIC void machine_i2c_obj_init_helper(machine_i2c_obj_t *self, mp_uint_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) { - enum { ARG_scl, ARG_sda, ARG_freq }; + enum { ARG_scl, ARG_sda, ARG_freq, ARG_timeout }; static const mp_arg_t allowed_args[] = { { MP_QSTR_scl, MP_ARG_REQUIRED | MP_ARG_OBJ }, { MP_QSTR_sda, MP_ARG_REQUIRED | MP_ARG_OBJ }, { 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 = 255} }, }; mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)]; mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args); self->scl = mp_hal_get_pin_obj(args[ARG_scl].u_obj); self->sda = mp_hal_get_pin_obj(args[ARG_sda].u_obj); + self->us_timeout = args[ARG_timeout].u_int; mp_hal_i2c_init(self, args[ARG_freq].u_int); } |