Allow uP allocated buffer for Plasma LEDs

libraries/plasma2040/apa102.cpp

@@ -2,7 +2,7 @@
 
 namespace plasma {
 
-APA102::APA102(uint num_leds, PIO pio, uint sm, uint pin_dat, uint pin_clk, uint freq) : num_leds(num_leds), pio(pio), sm(sm) {
+APA102::APA102(uint num_leds, PIO pio, uint sm, uint pin_dat, uint pin_clk, uint freq, RGB* buffer) : buffer(buffer), num_leds(num_leds), pio(pio), sm(sm) {
     uint offset = pio_add_program(pio, &apa102_program);
 
     pio_sm_set_pins_with_mask(pio, sm, 0, (1u << pin_clk) | (1u << pin_dat));
@@ -32,7 +32,9 @@ APA102::APA102(uint num_leds, PIO pio, uint sm, uint pin_dat, uint pin_clk, uint
     channel_config_set_read_increment(&config, true);
     dma_channel_configure(dma_channel, &config, &pio->txf[sm], NULL, 0, false);
 
-    buffer = new RGB[num_leds];
+    if(this->buffer == nullptr) {
+        this->buffer = new RGB[num_leds];
+    }
 }
 
 bool APA102::dma_timer_callback(struct repeating_timer *t) {

libraries/plasma2040/apa102.hpp

@@ -54,7 +54,7 @@ namespace plasma {
             RGB *buffer;
             uint32_t num_leds;
 
-            APA102(uint num_leds, PIO pio, uint sm, uint pin_dat, uint pin_clk, uint freq=DEFAULT_SERIAL_FREQ);
+            APA102(uint num_leds, PIO pio, uint sm, uint pin_dat, uint pin_clk, uint freq=DEFAULT_SERIAL_FREQ, RGB* buffer=nullptr);
             ~APA102() {
                 stop();
                 clear();

libraries/plasma2040/ws2812.cpp

@@ -2,7 +2,7 @@
 
 namespace plasma {
 
-WS2812::WS2812(uint num_leds, PIO pio, uint sm, uint pin, uint freq) : num_leds(num_leds), pio(pio), sm(sm) {
+WS2812::WS2812(uint num_leds, PIO pio, uint sm, uint pin, uint freq, RGB* buffer) : buffer(buffer), num_leds(num_leds), pio(pio), sm(sm) {
     uint offset = pio_add_program(pio, &ws2812_program);
 
     pio_gpio_init(pio, pin);
@@ -31,7 +31,9 @@ WS2812::WS2812(uint num_leds, PIO pio, uint sm, uint pin, uint freq) : num_leds(
     dma_channel_set_read_addr(dma_channel, (uint32_t *)buffer, false);
     dma_channel_configure(dma_channel, &config, &pio->txf[sm], NULL, 0, false);
 
-    buffer = new RGB[num_leds];
+    if(!this->buffer) {
+        this->buffer = new RGB[num_leds];
+    }
 }
 
 bool WS2812::dma_timer_callback(struct repeating_timer *t) {

libraries/plasma2040/ws2812.hpp

@@ -54,7 +54,7 @@ namespace plasma {
             RGB *buffer;
             uint32_t num_leds;
 
-            WS2812(uint num_leds, PIO pio, uint sm, uint pin, uint freq=DEFAULT_SERIAL_FREQ);
+            WS2812(uint num_leds, PIO pio, uint sm, uint pin, uint freq=DEFAULT_SERIAL_FREQ, RGB* buffer=nullptr);
             ~WS2812() {
                 stop();
                 clear();

micropython/modules/plasma_2040/plasma_2040.cpp

@@ -27,6 +27,7 @@ const mp_obj_float_t const_float_1 = {{&mp_type_float}, 1.0f};
 typedef struct _PlasmaWS2812_obj_t {
     mp_obj_base_t base;
     WS2812* ws2812;
+    void *buf;
 } _PlasmaWS2812_obj_t;
 
 
@@ -58,7 +59,8 @@ mp_obj_t PlasmaWS2812_make_new(const mp_obj_type_t *type, size_t n_args, size_t
         ARG_pio,
         ARG_sm,
         ARG_dat,
-        ARG_freq
+        ARG_freq,
+        ARG_buffer
     };
     static const mp_arg_t allowed_args[] = {
         { MP_QSTR_num_leds, MP_ARG_REQUIRED | MP_ARG_INT },
@@ -66,6 +68,7 @@ mp_obj_t PlasmaWS2812_make_new(const mp_obj_type_t *type, size_t n_args, size_t
         { MP_QSTR_sm, MP_ARG_REQUIRED | MP_ARG_INT },
         { MP_QSTR_dat, MP_ARG_REQUIRED | MP_ARG_INT },
         { MP_QSTR_freq, MP_ARG_INT, {.u_int = WS2812::DEFAULT_SERIAL_FREQ} },
+        { MP_QSTR_buffer, MP_ARG_OBJ, {.u_obj = nullptr} },
     };
 
     // Parse args.
@@ -78,10 +81,22 @@ mp_obj_t PlasmaWS2812_make_new(const mp_obj_type_t *type, size_t n_args, size_t
     int dat = args[ARG_dat].u_int;
     int freq = args[ARG_freq].u_int;
 
+    void *buffer = nullptr;
+
+    if (args[ARG_buffer].u_obj) {
+        mp_buffer_info_t bufinfo;
+        mp_get_buffer_raise(args[ARG_buffer].u_obj, &bufinfo, MP_BUFFER_RW);
+        buffer = bufinfo.buf;
+        if(bufinfo.len < (size_t)(num_leds * 4)) {
+            mp_raise_ValueError("Supplied buffer is too small for LED count!");
+        }
+    }
+
     self = m_new_obj_with_finaliser(_PlasmaWS2812_obj_t);
     self->base.type = &PlasmaWS2812_type;
+    self->buf = buffer;
 
-    self->ws2812 = new WS2812(num_leds, pio, sm, dat, freq);
+    self->ws2812 = new WS2812(num_leds, pio, sm, dat, freq, (WS2812::RGB *)buffer);
 
     return MP_OBJ_FROM_PTR(self);
 }
@@ -166,6 +181,7 @@ mp_obj_t PlasmaWS2812_set_hsv(size_t n_args, const mp_obj_t *pos_args, mp_map_t
 typedef struct _PlasmaAPA102_obj_t {
     mp_obj_base_t base;
     APA102* apa102;
+    void *buf;
 } _PlasmaAPA102_obj_t;
 
 
@@ -198,7 +214,8 @@ mp_obj_t PlasmaAPA102_make_new(const mp_obj_type_t *type, size_t n_args, size_t
         ARG_sm,
         ARG_dat,
         ARG_clk,
-        ARG_freq
+        ARG_freq,
+        ARG_buffer
     };
     static const mp_arg_t allowed_args[] = {
         { MP_QSTR_num_leds, MP_ARG_REQUIRED | MP_ARG_INT },
@@ -207,6 +224,7 @@ mp_obj_t PlasmaAPA102_make_new(const mp_obj_type_t *type, size_t n_args, size_t
         { MP_QSTR_dat, MP_ARG_REQUIRED | MP_ARG_INT },
         { MP_QSTR_clk, MP_ARG_REQUIRED | MP_ARG_INT },
         { MP_QSTR_freq, MP_ARG_INT, {.u_int = APA102::DEFAULT_SERIAL_FREQ} },
+        { MP_QSTR_buffer, MP_ARG_OBJ, {.u_obj = nullptr} },
     };
 
     // Parse args.
@@ -220,10 +238,22 @@ mp_obj_t PlasmaAPA102_make_new(const mp_obj_type_t *type, size_t n_args, size_t
     int clk = args[ARG_clk].u_int;
     int freq = args[ARG_freq].u_int;
 
+    void *buffer = nullptr;
+
+    if (args[ARG_buffer].u_obj) {
+        mp_buffer_info_t bufinfo;
+        mp_get_buffer_raise(args[ARG_buffer].u_obj, &bufinfo, MP_BUFFER_RW);
+        buffer = bufinfo.buf;
+        if(bufinfo.len < (size_t)(num_leds * 4)) {
+            mp_raise_ValueError("Supplied buffer is too small for LED count!");
+        }
+    }
+
     self = m_new_obj_with_finaliser(_PlasmaAPA102_obj_t);
     self->base.type = &PlasmaAPA102_type;
+    self->buf = buffer;
 
-    self->apa102 = new APA102(num_leds, pio, sm, dat, clk, freq);
+    self->apa102 = new APA102(num_leds, pio, sm, dat, clk, freq, (APA102::RGB *)buffer);
 
     return MP_OBJ_FROM_PTR(self);
 }