Add gpio:set_int/4 for ESP32 and STM32

Allows setting the pid() or registered name of the process to receive GPIO
interrupt messages as the fourth parameter of `gpio:set_int/4`, for both
ESP32 and STM32 GPIO port drivers.

Signed-off-by: Winford <[email protected]>

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Added `esp:get_default_mac/0` for retrieving the default MAC address on ESP32.
 - Added support for `pico` and `poci` as an alternative to `mosi` and `miso` for SPI
 - ESP32: Added support to SPI peripherals other than hspi and vspi
+- Added `gpio:set_int/4`, with the 4th parameter being the pid() or registered name of the process to receive interrupt messages
 
 ### Changed
 

libs/eavmlib/src/gpio.erl

@@ -36,7 +36,7 @@
     read/2,
     set_direction/3,
     set_level/3,
-    set_int/3,
+    set_int/3, set_int/4,
     remove_int/2,
     stop/0,
     close/1
@@ -251,6 +251,31 @@ set_level(GPIO, Pin, Level) ->
 set_int(GPIO, Pin, Trigger) ->
     port:call(GPIO, {set_int, Pin, Trigger}).
 
+%%-----------------------------------------------------------------------------
+%% @param   GPIO pid that was returned from `gpio:start/0'
+%% @param   Pin number of the pin to set the interrupt on
+%% @param   Trigger is the state that will trigger an interrupt
+%% @param   Pid is the process that will receive the interrupt message
+%% @returns ok | error | {error, Reason}
+%% @doc     Set a GPIO interrupt
+%%
+%%          Available triggers are `none' (which is the same as disabling an
+%%          interrupt), `rising', `falling', `both' (rising or falling), `low', and
+%%          `high'. When the interrupt is triggered it will send a tuple:
+%%            `{gpio_interrupt, Pin}'
+%%          to the process that set the interrupt. Pin will be the number
+%%          of the pin that triggered the interrupt.
+%%
+%%          The STM32 port only supports `rising', `falling', or `both'.
+%%
+%%          The rp2040 (Pico) port does not support gpio interrupts at this time.
+%% @end
+%%-----------------------------------------------------------------------------
+-spec set_int(GPIO :: gpio(), Pin :: pin(), Trigger :: trigger(), Pid :: pid()) ->
+    ok | {error, Reason :: atom()} | error.
+set_int(GPIO, Pin, Trigger, Pid) ->
+    port:call(GPIO, {set_int, Pin, Trigger, Pid}).
+
 %%-----------------------------------------------------------------------------
 %% @param   GPIO pid that was returned from `gpio:start/0'
 %% @param   Pin number of the pin to remove the interrupt

src/platforms/esp32/components/avm_builtins/gpio_driver.c

@@ -32,7 +32,6 @@
 #include "atom.h"
 #include "bif.h"
 #include "context.h"
-#include "scheduler.h"
 #include "debug.h"
 #include "defaultatoms.h"
 #include "globalcontext.h"
@@ -41,6 +40,7 @@
 #include "module.h"
 #include "nifs.h"
 #include "platform_defaultatoms.h"
+#include "scheduler.h"
 #include "term.h"
 #include "utils.h"
 
@@ -133,6 +133,8 @@ struct GPIOData
     struct ListHead gpio_listeners;
 };
 
+/* TODO: Change error returns to {error, Reason} (See: https://github.com/atomvm/AtomVM/issues/894) */
+
 static inline term gpio_set_pin_mode(Context *ctx, term gpio_num_term, term mode_term)
 {
     int gpio_num = term_to_int(gpio_num_term);
@@ -343,16 +345,38 @@ static bool gpiodriver_is_gpio_attached(struct GPIOData *gpio_data, int gpio_num
 static term gpiodriver_set_int(Context *ctx, int32_t target_pid, term cmd)
 {
     GlobalContext *glb = ctx->global;
+    int32_t target_local_pid;
 
     struct GPIOData *gpio_data = ctx->platform_data;
 
     int32_t gpio_num = term_to_int32(term_get_tuple_element(cmd, 1));
     term trigger = term_get_tuple_element(cmd, 2);
+    if (term_get_tuple_arity(cmd) == 4) {
+        term pid = term_get_tuple_element(cmd, 3);
+        if (UNLIKELY(!term_is_pid(pid) && !term_is_atom(pid))) {
+            ESP_LOGE(TAG, "Invalid listener parameter, must be a pid() or registered process!");
+            return ERROR_ATOM;
+        }
+        if (term_is_pid(pid)) {
+            target_local_pid = term_to_local_process_id(pid);
+        } else {
+            int pid_atom_index = term_to_atom_index(pid);
+            int32_t registered_process = (int32_t) globalcontext_get_registered_process(ctx->global, pid_atom_index);
+            if (UNLIKELY(registered_process == 0)) {
+                ESP_LOGE(TAG, "Invalid listener parameter, atom() is not a registered process name!");
+                return ERROR_ATOM;
+            }
+            target_local_pid = registered_process;
+        }
+    } else {
+        target_local_pid = target_pid;
+    }
 
     if (gpiodriver_is_gpio_attached(gpio_data, gpio_num)) {
         return ERROR_ATOM;
     }
 
+    /* TODO: GPIO specific atoms should be removed from platform_defaultatoms and constructed within this driver */
     gpio_int_type_t interrupt_type;
     switch (trigger) {
         case NONE_ATOM:
@@ -397,7 +421,7 @@ static term gpiodriver_set_int(Context *ctx, int32_t target_pid, term cmd)
     }
     list_append(&gpio_data->gpio_listeners, &data->gpio_listener_list_head);
     data->gpio = gpio_num;
-    data->target_local_pid = target_pid;
+    data->target_local_pid = target_local_pid;
     sys_register_listener(glb, &data->listener);
     data->listener.sender = data;
     data->listener.handler = gpio_interrupt_callback;
@@ -523,6 +547,8 @@ REGISTER_PORT_DRIVER(gpio, gpio_driver_init, NULL, gpio_driver_create_port)
 
 #ifdef CONFIG_AVM_ENABLE_GPIO_NIFS
 
+/* TODO: in the case of {error, Return} we should RAISE_ERROR(Reason) */
+
 static term nif_gpio_set_pin_mode(Context *ctx, int argc, term argv[])
 {
     return gpio_set_pin_mode(ctx, argv[0], argv[1]);

src/platforms/stm32/src/lib/gpio_driver.c

@@ -71,6 +71,7 @@ static NativeHandlerResult consume_gpio_mailbox(Context *ctx);
 static const char *const gpio_atom = ATOM_STR("\x4", "gpio");
 static const char *const gpio_interrupt_atom = ATOM_STR("\xE", "gpio_interrupt");
 static const char *const invalid_trigger_atom = ATOM_STR("\xF", "invalid_trigger");
+static const char *const invalid_listener_atom = ATOM_STR("\x10", "invalid_listener");
 
 #define INVALID_EXTI_TRIGGER 0xEE
 
@@ -748,6 +749,8 @@ static bool gpiodriver_is_gpio_attached(struct GPIOData *gpio_data, term gpio_ba
 
 static term gpiodriver_set_int(Context *ctx, int32_t target_pid, term cmd)
 {
+    int32_t target_local_pid;
+
     term gpio_tuple = term_get_tuple_element(cmd, 1);
     if (UNLIKELY(!term_is_tuple(gpio_tuple))) {
         AVM_LOGE(TAG, "Invalid GPIO Pin tuple, expect {Bank, Pin}.");
@@ -789,6 +792,27 @@ static term gpiodriver_set_int(Context *ctx, int32_t target_pid, term cmd)
         return create_pair(ctx, ERROR_ATOM, globalcontext_make_atom(ctx->global, invalid_trigger_atom));
     }
 
+    if (term_get_tuple_arity(cmd) == 4) {
+        term pid = term_get_tuple_element(cmd, 3);
+        if (UNLIKELY(!term_is_pid(pid) && !term_is_atom(pid))) {
+            AVM_LOGE(TAG, "Invalid listener parameter, must be a pid() or registered process!");
+            return create_pair(ctx, ERROR_ATOM, invalid_listener_atom);
+        }
+        if (term_is_pid(pid)) {
+            target_local_pid = term_to_local_process_id(pid);
+        } else {
+            int pid_atom_index = term_to_atom_index(pid);
+            int32_t registered_process = (int32_t) globalcontext_get_registered_process(ctx->global, pid_atom_index);
+            if (UNLIKELY(registered_process == 0)) {
+                AVM_LOGE(TAG, "Invalid listener parameter, atom() is not a registered process name!");
+                return create_pair(ctx, ERROR_ATOM, NOPROC_ATOM);
+            }
+            target_local_pid = registered_process;
+        }
+    } else {
+        target_local_pid = target_pid;
+    }
+
     uint32_t exti = 1U << gpio_pin;
 
     if (!list_is_empty(&gpio_data->gpio_listeners)) {
@@ -816,7 +840,7 @@ static term gpiodriver_set_int(Context *ctx, int32_t target_pid, term cmd)
         AVM_ABORT();
     }
     list_append(&gpio_data->gpio_listeners, &data->gpio_listener_list_head);
-    data->target_local_pid = target_pid;
+    data->target_local_pid = target_local_pid;
     data->bank_atom = gpio_bank_atom;
     data->gpio_pin = gpio_pin;
     data->exti = exti;