esp32/machine_pin: Add new hold keyword argument and remove PULL_HOLD.

The current pull=Pin.PULL_HOLD argument doesn't make a lot of sense in the
context of what it actually does vs what the ESP32 quickref document says
it does.

This commit removes PULL_HOLD and adds a new hold=True|False keyword
argument to Pin()/Pin.init().  Setting this to True will cause the ESP32 to
lock the configuration of the pin – including direction, output value,
drive strength, pull-up/-down – such that it can't be accidentally changed
and will be retained through a watchdog or internal reset.

Fixes issue #8283, and see also #8284.
This commit is contained in:
Jonathan Hogg 2022-03-07 09:21:11 +00:00 committed by Damien George
parent 5887dfeea6
commit 7684c996bc
2 changed files with 23 additions and 7 deletions

View File

@ -177,6 +177,14 @@ safe maximum source/sink currents and approximate internal driver resistances:
- ``Pin.DRIVE_2``: 20mA / 30 ohm (default strength if not configured)
- ``Pin.DRIVE_3``: 40mA / 15 ohm
The ``hold=`` keyword argument to ``Pin()`` and ``Pin.init()`` will enable the
ESP32 "pad hold" feature. When set to ``True``, the pin configuration
(direction, pull resistors and output value) will be held and any further
changes (including changing the output level) will not be applied. Setting
``hold=False`` will immediately apply any outstanding pin configuration changes
and release the pin. Using ``hold=True`` while a pin is already held will apply
any configuration changes and then immediately reapply the hold.
Notes:
* Pins 1 and 3 are REPL UART TX and RX respectively
@ -549,6 +557,10 @@ deep-sleep mode::
pin.init(pull=None)
machine.deepsleep(10000)
Output-configured RTC pins will also retain their output direction and level in
deep-sleep if pad hold is enabled with the ``hold=True`` argument to
``Pin.init()``.
Non-RTC GPIO pins will be disconnected by default on entering deep-sleep.
SD card

View File

@ -47,7 +47,6 @@
// Used to implement a range of pull capabilities
#define GPIO_PULL_DOWN (1)
#define GPIO_PULL_UP (2)
#define GPIO_PULL_HOLD (4)
#if CONFIG_IDF_TARGET_ESP32
#define GPIO_FIRST_NON_OUTPUT (34)
@ -253,14 +252,15 @@ STATIC void machine_pin_print(const mp_print_t *print, mp_obj_t self_in, mp_prin
mp_printf(print, "Pin(%u)", self->id);
}
// pin.init(mode=None, pull=-1, *, value, drive)
// pin.init(mode=None, pull=-1, *, value, drive, hold)
STATIC mp_obj_t machine_pin_obj_init_helper(const machine_pin_obj_t *self, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
enum { ARG_mode, ARG_pull, ARG_value, ARG_drive };
enum { ARG_mode, ARG_pull, ARG_value, ARG_drive, ARG_hold };
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_mode, MP_ARG_OBJ, {.u_obj = mp_const_none}},
{ MP_QSTR_pull, MP_ARG_OBJ, {.u_obj = MP_OBJ_NEW_SMALL_INT(-1)}},
{ MP_QSTR_value, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL}},
{ MP_QSTR_drive, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL}},
{ MP_QSTR_hold, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL}},
};
// parse args
@ -325,10 +325,15 @@ STATIC mp_obj_t machine_pin_obj_init_helper(const machine_pin_obj_t *self, size_
} else {
gpio_pullup_dis(self->id);
}
if (mode & GPIO_PULL_HOLD) {
}
// configure pad hold
if (args[ARG_hold].u_obj != MP_OBJ_NULL && GPIO_IS_VALID_OUTPUT_GPIO(self->id)) {
// always disable pad hold to apply outstanding config changes
gpio_hold_dis(self->id);
// (re-)enable pad hold if requested
if (mp_obj_is_true(args[ARG_hold].u_obj)) {
gpio_hold_en(self->id);
} else if (GPIO_IS_VALID_OUTPUT_GPIO(self->id)) {
gpio_hold_dis(self->id);
}
}
@ -480,7 +485,6 @@ STATIC const mp_rom_map_elem_t machine_pin_locals_dict_table[] = {
{ MP_ROM_QSTR(MP_QSTR_OPEN_DRAIN), MP_ROM_INT(GPIO_MODE_INPUT_OUTPUT_OD) },
{ MP_ROM_QSTR(MP_QSTR_PULL_UP), MP_ROM_INT(GPIO_PULL_UP) },
{ MP_ROM_QSTR(MP_QSTR_PULL_DOWN), MP_ROM_INT(GPIO_PULL_DOWN) },
{ MP_ROM_QSTR(MP_QSTR_PULL_HOLD), MP_ROM_INT(GPIO_PULL_HOLD) },
{ MP_ROM_QSTR(MP_QSTR_IRQ_RISING), MP_ROM_INT(GPIO_PIN_INTR_POSEDGE) },
{ MP_ROM_QSTR(MP_QSTR_IRQ_FALLING), MP_ROM_INT(GPIO_PIN_INTR_NEGEDGE) },
{ MP_ROM_QSTR(MP_QSTR_WAKE_LOW), MP_ROM_INT(GPIO_PIN_INTR_LOLEVEL) },