esp8266: Implement Pin.__call__() and Pin.OPEN_DRAIN mode.

OPEN_DRAIN is of course synthesised.  All pin modes are tested and
working.

esp8266/modpybpin.c

@@ -38,6 +38,7 @@
 
 #define GPIO_MODE_INPUT (0)
 #define GPIO_MODE_OUTPUT (1)
+#define GPIO_MODE_OPEN_DRAIN (2) // synthesised
 #define GPIO_PULL_NONE (0)
 #define GPIO_PULL_UP (1)
 // Removed in SDK 1.1.0
@@ -66,6 +67,42 @@ STATIC const pyb_pin_obj_t pyb_pin_obj[] = {
     {{&pyb_pin_type}, 15, 15, PERIPHS_IO_MUX_MTDO_U, FUNC_GPIO15},
 };
 
+STATIC uint8_t pin_mode[16];
+
+STATIC void pin_set(uint pin, uint mode, int value) {
+    uint32_t enable = 0;
+    uint32_t disable = 0;
+    switch (mode) {
+        case GPIO_MODE_INPUT:
+            value = -1;
+            disable = 1;
+            break;
+
+        case GPIO_MODE_OUTPUT:
+            enable = 1;
+            break;
+
+        case GPIO_MODE_OPEN_DRAIN:
+            if (value == -1) {
+                return;
+            } else if (value == 0) {
+                enable = 1;
+            } else {
+                value = -1;
+                disable = 1;
+            }
+            break;
+    }
+
+    enable <<= pin;
+    disable <<= pin;
+    if (value == -1) {
+        gpio_output_set(0, 0, enable, disable);
+    } else {
+        gpio_output_set(value << pin, (1 - value) << pin, enable, disable);
+    }
+}
+
 STATIC void pyb_pin_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
     pyb_pin_obj_t *self = self_in;
 
@@ -78,17 +115,32 @@ STATIC mp_obj_t pyb_pin_obj_init_helper(pyb_pin_obj_t *self, mp_uint_t n_args, c
     static const mp_arg_t allowed_args[] = {
         { MP_QSTR_mode, MP_ARG_REQUIRED | MP_ARG_INT },
         { MP_QSTR_pull, MP_ARG_INT, {.u_int = GPIO_PULL_NONE}},
+        { MP_QSTR_value, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL}},
     };
 
     // parse args
-    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);
+    struct {
+        mp_arg_val_t mode, pull, value;
+    } args;
+    mp_arg_parse_all(n_args, pos_args, kw_args,
+        MP_ARRAY_SIZE(allowed_args), allowed_args, (mp_arg_val_t*)&args);
 
     // get io mode
-    uint mode = args[0].u_int;
+    uint mode = args.mode.u_int;
 
     // get pull mode
-    uint pull = args[1].u_int;
+    uint pull = args.pull.u_int;
+
+    // get initial value
+    int value;
+    if (args.value.u_obj == MP_OBJ_NULL) {
+        value = -1;
+    } else {
+        value = mp_obj_is_true(args.value.u_obj);
+    }
+
+    // save the mode
+    pin_mode[self->phys_port] = mode;
 
     // configure the GPIO as requested
     PIN_FUNC_SELECT(self->periph, self->func);
@@ -110,10 +162,7 @@ STATIC mp_obj_t pyb_pin_obj_init_helper(pyb_pin_obj_t *self, mp_uint_t n_args, c
         PIN_PULLUP_EN(self->periph);
     }
 
-    // TODO input mode is not working...
-    if ((mode & GPIO_MODE_OUTPUT) == 0) {
-        GPIO_DIS_OUTPUT(self->phys_port);
-    }
+    pin_set(self->phys_port, mode, value);
 
     return mp_const_none;
 }
@@ -145,6 +194,20 @@ STATIC mp_obj_t pyb_pin_make_new(const mp_obj_type_t *type, mp_uint_t n_args, mp
     return (mp_obj_t)pin;
 }
 
+// fast method for getting/setting pin value
+STATIC mp_obj_t pyb_pin_call(mp_obj_t self_in, mp_uint_t n_args, mp_uint_t n_kw, const mp_obj_t *args) {
+    mp_arg_check_num(n_args, n_kw, 0, 1, false);
+    pyb_pin_obj_t *self = self_in;
+    if (n_args == 0) {
+        // get pin
+        return MP_OBJ_NEW_SMALL_INT(GPIO_INPUT_GET(self->phys_port));
+    } else {
+        // set pin
+        pin_set(self->phys_port, pin_mode[self->phys_port], mp_obj_is_true(args[0]));
+        return mp_const_none;
+    }
+}
+
 // pin.init(mode, pull)
 STATIC mp_obj_t pyb_pin_obj_init(mp_uint_t n_args, const mp_obj_t *args, mp_map_t *kw_args) {
     return pyb_pin_obj_init_helper(args[0], n_args - 1, args + 1, kw_args);
@@ -153,26 +216,14 @@ MP_DEFINE_CONST_FUN_OBJ_KW(pyb_pin_init_obj, 1, pyb_pin_obj_init);
 
 // pin.value([value])
 STATIC mp_obj_t pyb_pin_value(mp_uint_t n_args, const mp_obj_t *args) {
-    pyb_pin_obj_t *self = args[0];
-    if (n_args == 1) {
-        // get pin
-        return MP_OBJ_NEW_SMALL_INT(GPIO_INPUT_GET(self->phys_port));
-    } else {
-        // set pin
-        if (mp_obj_is_true(args[1])) {
-            GPIO_OUTPUT_SET(self->phys_port, 1);
-        } else {
-            GPIO_OUTPUT_SET(self->phys_port, 0);
-        }
-        return mp_const_none;
-    }
+    return pyb_pin_call(args[0], n_args - 1, 0, args + 1);
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pyb_pin_value_obj, 1, 2, pyb_pin_value);
 
 // pin.low()
 STATIC mp_obj_t pyb_pin_low(mp_obj_t self_in) {
     pyb_pin_obj_t *self = self_in;
-    GPIO_OUTPUT_SET(self->phys_port, 0);
+    pin_set(self->phys_port, pin_mode[self->phys_port], 0);
     return mp_const_none;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_pin_low_obj, pyb_pin_low);
@@ -180,7 +231,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_pin_low_obj, pyb_pin_low);
 // pin.high()
 STATIC mp_obj_t pyb_pin_high(mp_obj_t self_in) {
     pyb_pin_obj_t *self = self_in;
-    GPIO_OUTPUT_SET(self->phys_port, 1);
+    pin_set(self->phys_port, pin_mode[self->phys_port], 1);
     return mp_const_none;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_pin_high_obj, pyb_pin_high);
@@ -194,7 +245,8 @@ STATIC const mp_map_elem_t pyb_pin_locals_dict_table[] = {
 
     // class constants
     { MP_OBJ_NEW_QSTR(MP_QSTR_IN),        MP_OBJ_NEW_SMALL_INT(GPIO_MODE_INPUT) },
-    { MP_OBJ_NEW_QSTR(MP_QSTR_OUT_PP),    MP_OBJ_NEW_SMALL_INT(GPIO_MODE_OUTPUT) },
+    { MP_OBJ_NEW_QSTR(MP_QSTR_OUT),       MP_OBJ_NEW_SMALL_INT(GPIO_MODE_OUTPUT) },
+    { MP_OBJ_NEW_QSTR(MP_QSTR_OPEN_DRAIN), MP_OBJ_NEW_SMALL_INT(GPIO_MODE_OPEN_DRAIN) },
     { MP_OBJ_NEW_QSTR(MP_QSTR_PULL_NONE), MP_OBJ_NEW_SMALL_INT(GPIO_PULL_NONE) },
     { MP_OBJ_NEW_QSTR(MP_QSTR_PULL_UP),   MP_OBJ_NEW_SMALL_INT(GPIO_PULL_UP) },
     //{ MP_OBJ_NEW_QSTR(MP_QSTR_PULL_DOWN), MP_OBJ_NEW_SMALL_INT(GPIO_PULL_DOWN) },
@@ -207,5 +259,6 @@ const mp_obj_type_t pyb_pin_type = {
     .name = MP_QSTR_Pin,
     .print = pyb_pin_print,
     .make_new = pyb_pin_make_new,
+    .call = pyb_pin_call,
     .locals_dict = (mp_obj_t)&pyb_pin_locals_dict,
 };

esp8266/qstrdefsport.h

@@ -120,8 +120,8 @@ Q(value)
 Q(low)
 Q(high)
 Q(IN)
-Q(OUT_PP)
-Q(OUT_OD)
+Q(OUT)
+Q(OPEN_DRAIN)
 Q(PULL_NONE)
 Q(PULL_UP)
 Q(PULL_DOWN)