add circuitpython code

1 files changed, 453 insertions, 0 deletions

diff --git a/circuitpython/shared-module/displayio/EPaperDisplay.c b/circuitpython/shared-module/displayio/EPaperDisplay.c
new file mode 100644
index 0000000..b1e9980
--- /dev/null
+++ b/circuitpython/shared-module/displayio/EPaperDisplay.c
@@ -0,0 +1,453 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Scott Shawcroft for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "shared-bindings/displayio/EPaperDisplay.h"
+
+#include "py/gc.h"
+#include "py/runtime.h"
+#include "shared-bindings/displayio/ColorConverter.h"
+#include "shared-bindings/displayio/FourWire.h"
+#include "shared-bindings/displayio/I2CDisplay.h"
+#if CIRCUITPY_PARALLELDISPLAY
+#include "shared-bindings/paralleldisplay/ParallelBus.h"
+#endif
+#include "shared-bindings/microcontroller/Pin.h"
+#include "shared-bindings/time/__init__.h"
+#include "shared-module/displayio/__init__.h"
+#include "supervisor/shared/display.h"
+#include "supervisor/shared/tick.h"
+#include "supervisor/usb.h"
+
+#include <stdint.h>
+#include <string.h>
+
+#define DELAY 0x80
+
+void common_hal_displayio_epaperdisplay_construct(displayio_epaperdisplay_obj_t *self,
+    mp_obj_t bus, const uint8_t *start_sequence, uint16_t start_sequence_len,
+    const uint8_t *stop_sequence, uint16_t stop_sequence_len,
+    uint16_t width, uint16_t height, uint16_t ram_width, uint16_t ram_height,
+    int16_t colstart, int16_t rowstart, uint16_t rotation,
+    uint16_t set_column_window_command, uint16_t set_row_window_command,
+    uint16_t set_current_column_command, uint16_t set_current_row_command,
+    uint16_t write_black_ram_command, bool black_bits_inverted, uint16_t write_color_ram_command, bool color_bits_inverted, uint32_t highlight_color, uint16_t refresh_display_command, mp_float_t refresh_time,
+    const mcu_pin_obj_t *busy_pin, bool busy_state, mp_float_t seconds_per_frame, bool chip_select, bool grayscale, bool two_byte_sequence_length) {
+    if (highlight_color != 0x000000) {
+        self->core.colorspace.tricolor = true;
+        self->core.colorspace.tricolor_hue = displayio_colorconverter_compute_hue(highlight_color);
+        self->core.colorspace.tricolor_luma = displayio_colorconverter_compute_luma(highlight_color);
+    }
+
+    displayio_display_core_construct(&self->core, bus, width, height, ram_width, ram_height, colstart, rowstart, rotation, 1, true, true, 1, true, true);
+
+    self->set_column_window_command = set_column_window_command;
+    self->set_row_window_command = set_row_window_command;
+    self->set_current_column_command = set_current_column_command;
+    self->set_current_row_command = set_current_row_command;
+    self->write_black_ram_command = write_black_ram_command;
+    self->black_bits_inverted = black_bits_inverted;
+    self->write_color_ram_command = write_color_ram_command;
+    self->color_bits_inverted = color_bits_inverted;
+    self->refresh_display_command = refresh_display_command;
+    self->refresh_time = refresh_time * 1000;
+    self->busy_state = busy_state;
+    self->refreshing = false;
+    self->milliseconds_per_frame = seconds_per_frame * 1000;
+    self->chip_select = chip_select ? CHIP_SELECT_TOGGLE_EVERY_BYTE : CHIP_SELECT_UNTOUCHED;
+    self->grayscale = grayscale;
+
+    self->start_sequence = start_sequence;
+    self->start_sequence_len = start_sequence_len;
+    self->stop_sequence = stop_sequence;
+    self->stop_sequence_len = stop_sequence_len;
+
+    self->busy.base.type = &mp_type_NoneType;
+    self->two_byte_sequence_length = two_byte_sequence_length;
+    if (busy_pin != NULL) {
+        self->busy.base.type = &digitalio_digitalinout_type;
+        common_hal_digitalio_digitalinout_construct(&self->busy, busy_pin);
+        common_hal_never_reset_pin(busy_pin);
+    }
+
+    // Clear the color memory if it isn't in use.
+    if (highlight_color == 0x00 && write_color_ram_command != NO_COMMAND) {
+        // TODO: Clear
+    }
+
+    // Set the group after initialization otherwise we may send pixels while we delay in
+    // initialization.
+    common_hal_displayio_epaperdisplay_show(self, &circuitpython_splash);
+}
+
+bool common_hal_displayio_epaperdisplay_show(displayio_epaperdisplay_obj_t *self, displayio_group_t *root_group) {
+    return displayio_display_core_show(&self->core, root_group);
+}
+
+STATIC const displayio_area_t *displayio_epaperdisplay_get_refresh_areas(displayio_epaperdisplay_obj_t *self) {
+    if (self->core.full_refresh) {
+        self->core.area.next = NULL;
+        return &self->core.area;
+    }
+    const displayio_area_t *first_area = NULL;
+    if (self->core.current_group != NULL) {
+        first_area = displayio_group_get_refresh_areas(self->core.current_group, NULL);
+    }
+    if (first_area != NULL && self->set_row_window_command == NO_COMMAND) {
+        self->core.area.next = NULL;
+        return &self->core.area;
+    }
+    return first_area;
+}
+
+uint16_t common_hal_displayio_epaperdisplay_get_width(displayio_epaperdisplay_obj_t *self) {
+    return displayio_display_core_get_width(&self->core);
+}
+
+uint16_t common_hal_displayio_epaperdisplay_get_height(displayio_epaperdisplay_obj_t *self) {
+    return displayio_display_core_get_height(&self->core);
+}
+
+STATIC void wait_for_busy(displayio_epaperdisplay_obj_t *self) {
+    if (self->busy.base.type == &mp_type_NoneType) {
+        return;
+    }
+    while (common_hal_digitalio_digitalinout_get_value(&self->busy) == self->busy_state) {
+        RUN_BACKGROUND_TASKS;
+    }
+}
+
+STATIC void send_command_sequence(displayio_epaperdisplay_obj_t *self,
+    bool should_wait_for_busy, const uint8_t *sequence, uint32_t sequence_len) {
+    uint32_t i = 0;
+    while (i < sequence_len) {
+        const uint8_t *cmd = sequence + i;
+        uint8_t data_size = *(cmd + 1);
+        bool delay = (data_size & DELAY) != 0;
+        const uint8_t *data = cmd + 2;
+        data_size &= ~DELAY;
+        if (self->two_byte_sequence_length) {
+            data_size = ((data_size & ~DELAY) << 8) + *(cmd + 2);
+            data = cmd + 3;
+        }
+        displayio_display_core_begin_transaction(&self->core);
+        self->core.send(self->core.bus, DISPLAY_COMMAND, self->chip_select, cmd, 1);
+        self->core.send(self->core.bus, DISPLAY_DATA, self->chip_select, data, data_size);
+        displayio_display_core_end_transaction(&self->core);
+        uint16_t delay_length_ms = 0;
+        if (delay) {
+            data_size++;
+            delay_length_ms = *(cmd + 1 + data_size);
+            if (delay_length_ms == 255) {
+                delay_length_ms = 500;
+            }
+        }
+        common_hal_time_delay_ms(delay_length_ms);
+        if (should_wait_for_busy) {
+            wait_for_busy(self);
+        }
+        i += 2 + data_size;
+        if (self->two_byte_sequence_length) {
+            i++;
+        }
+    }
+}
+
+void displayio_epaperdisplay_change_refresh_mode_parameters(displayio_epaperdisplay_obj_t *self,
+    mp_buffer_info_t *start_sequence, float seconds_per_frame) {
+    self->start_sequence = (uint8_t *)start_sequence->buf;
+    self->start_sequence_len = start_sequence->len;
+    self->milliseconds_per_frame = seconds_per_frame * 1000;
+}
+
+STATIC void displayio_epaperdisplay_start_refresh(displayio_epaperdisplay_obj_t *self) {
+    // run start sequence
+    self->core.bus_reset(self->core.bus);
+
+    send_command_sequence(self, true, self->start_sequence, self->start_sequence_len);
+    displayio_display_core_start_refresh(&self->core);
+}
+
+uint32_t common_hal_displayio_epaperdisplay_get_time_to_refresh(displayio_epaperdisplay_obj_t *self) {
+    if (self->core.last_refresh == 0) {
+        return 0;
+    }
+    // Refresh at seconds per frame rate.
+    uint32_t elapsed_time = supervisor_ticks_ms64() - self->core.last_refresh;
+    if (elapsed_time > self->milliseconds_per_frame) {
+        return 0;
+    }
+    return self->milliseconds_per_frame - elapsed_time;
+}
+
+STATIC void displayio_epaperdisplay_finish_refresh(displayio_epaperdisplay_obj_t *self) {
+    // Actually refresh the display now that all pixel RAM has been updated.
+    displayio_display_core_begin_transaction(&self->core);
+    self->core.send(self->core.bus, DISPLAY_COMMAND, self->chip_select, &self->refresh_display_command, 1);
+    displayio_display_core_end_transaction(&self->core);
+    supervisor_enable_tick();
+    self->refreshing = true;
+
+    displayio_display_core_finish_refresh(&self->core);
+}
+
+mp_obj_t common_hal_displayio_epaperdisplay_get_bus(displayio_epaperdisplay_obj_t *self) {
+    return self->core.bus;
+}
+
+void common_hal_displayio_epaperdisplay_set_rotation(displayio_epaperdisplay_obj_t *self, int rotation) {
+    bool transposed = (self->core.rotation == 90 || self->core.rotation == 270);
+    bool will_transposed = (rotation == 90 || rotation == 270);
+    if (transposed != will_transposed) {
+        int tmp = self->core.width;
+        self->core.width = self->core.height;
+        self->core.height = tmp;
+    }
+    displayio_display_core_set_rotation(&self->core, rotation);
+    if (self == &displays[0].epaper_display) {
+        supervisor_stop_terminal();
+        supervisor_start_terminal(self->core.width, self->core.height);
+    }
+    if (self->core.current_group != NULL) {
+        displayio_group_update_transform(self->core.current_group, &self->core.transform);
+    }
+}
+
+uint16_t common_hal_displayio_epaperdisplay_get_rotation(displayio_epaperdisplay_obj_t *self) {
+    return self->core.rotation;
+}
+
+
+STATIC bool displayio_epaperdisplay_refresh_area(displayio_epaperdisplay_obj_t *self, const displayio_area_t *area) {
+    uint16_t buffer_size = 128; // In uint32_ts
+
+    displayio_area_t clipped;
+    // Clip the area to the display by overlapping the areas. If there is no overlap then we're done.
+    if (!displayio_display_core_clip_area(&self->core, area, &clipped)) {
+        return true;
+    }
+    uint16_t subrectangles = 1;
+    uint16_t rows_per_buffer = displayio_area_height(&clipped);
+    uint8_t pixels_per_word = (sizeof(uint32_t) * 8) / self->core.colorspace.depth;
+    uint16_t pixels_per_buffer = displayio_area_size(&clipped);
+    if (displayio_area_size(&clipped) > buffer_size * pixels_per_word) {
+        rows_per_buffer = buffer_size * pixels_per_word / displayio_area_width(&clipped);
+        if (rows_per_buffer == 0) {
+            rows_per_buffer = 1;
+        }
+        subrectangles = displayio_area_height(&clipped) / rows_per_buffer;
+        if (displayio_area_height(&clipped) % rows_per_buffer != 0) {
+            subrectangles++;
+        }
+        pixels_per_buffer = rows_per_buffer * displayio_area_width(&clipped);
+        buffer_size = pixels_per_buffer / pixels_per_word;
+        if (pixels_per_buffer % pixels_per_word) {
+            buffer_size += 1;
+        }
+    }
+
+    // Allocated and shared as a uint32_t array so the compiler knows the
+    // alignment everywhere.
+    uint32_t buffer[buffer_size];
+    volatile uint32_t mask_length = (pixels_per_buffer / 32) + 1;
+    uint32_t mask[mask_length];
+
+    uint8_t passes = 1;
+    if (self->core.colorspace.tricolor || self->grayscale) {
+        passes = 2;
+    }
+    for (uint8_t pass = 0; pass < passes; pass++) {
+        uint16_t remaining_rows = displayio_area_height(&clipped);
+
+        if (self->set_row_window_command != NO_COMMAND) {
+            displayio_display_core_set_region_to_update(&self->core, self->set_column_window_command,
+                self->set_row_window_command, self->set_current_column_command, self->set_current_row_command,
+                false, self->chip_select, &clipped, false /* SH1107_addressing */);
+        }
+
+        uint8_t write_command = self->write_black_ram_command;
+        if (pass == 1) {
+            write_command = self->write_color_ram_command;
+        }
+        displayio_display_core_begin_transaction(&self->core);
+        self->core.send(self->core.bus, DISPLAY_COMMAND, self->chip_select, &write_command, 1);
+        displayio_display_core_end_transaction(&self->core);
+
+        for (uint16_t j = 0; j < subrectangles; j++) {
+            displayio_area_t subrectangle = {
+                .x1 = clipped.x1,
+                .y1 = clipped.y1 + rows_per_buffer * j,
+                .x2 = clipped.x2,
+                .y2 = clipped.y1 + rows_per_buffer * (j + 1)
+            };
+            if (remaining_rows < rows_per_buffer) {
+                subrectangle.y2 = subrectangle.y1 + remaining_rows;
+            }
+            remaining_rows -= rows_per_buffer;
+
+
+            uint16_t subrectangle_size_bytes = displayio_area_size(&subrectangle) / (8 / self->core.colorspace.depth);
+
+            memset(mask, 0, mask_length * sizeof(mask[0]));
+            memset(buffer, 0, buffer_size * sizeof(buffer[0]));
+
+            self->core.colorspace.grayscale = true;
+            self->core.colorspace.grayscale_bit = 7;
+            if (pass == 1) {
+                if (self->grayscale) { // 4-color grayscale
+                    self->core.colorspace.grayscale_bit = 6;
+                } else { // Tri-color
+                    self->core.colorspace.grayscale = false;
+                }
+            }
+            displayio_display_core_fill_area(&self->core, &subrectangle, mask, buffer);
+
+            // Invert it all.
+            if ((pass == 1 && self->color_bits_inverted) ||
+                (pass == 0 && self->black_bits_inverted)) {
+                for (uint16_t k = 0; k < buffer_size; k++) {
+                    buffer[k] = ~buffer[k];
+                }
+            }
+
+            if (!displayio_display_core_begin_transaction(&self->core)) {
+                // Can't acquire display bus; skip the rest of the data. Try next display.
+                return false;
+            }
+            self->core.send(self->core.bus, DISPLAY_DATA, self->chip_select, (uint8_t *)buffer, subrectangle_size_bytes);
+            displayio_display_core_end_transaction(&self->core);
+
+            // TODO(tannewt): Make refresh displays faster so we don't starve other
+            // background tasks.
+            #if CIRCUITPY_USB
+            usb_background();
+            #endif
+        }
+    }
+
+    return true;
+}
+
+bool common_hal_displayio_epaperdisplay_refresh(displayio_epaperdisplay_obj_t *self) {
+
+    if (self->refreshing && self->busy.base.type == &digitalio_digitalinout_type) {
+        if (common_hal_digitalio_digitalinout_get_value(&self->busy) != self->busy_state) {
+            supervisor_disable_tick();
+            self->refreshing = false;
+            // Run stop sequence but don't wait for busy because busy is set when sleeping.
+            send_command_sequence(self, false, self->stop_sequence, self->stop_sequence_len);
+        } else {
+            return false;
+        }
+    }
+    if (self->core.current_group == NULL) {
+        return true;
+    }
+    // Refresh at seconds per frame rate.
+    if (common_hal_displayio_epaperdisplay_get_time_to_refresh(self) > 0) {
+        return false;
+    }
+    if (!displayio_display_core_bus_free(&self->core)) {
+        // Can't acquire display bus; skip updating this display. Try next display.
+        return false;
+    }
+    const displayio_area_t *current_area = displayio_epaperdisplay_get_refresh_areas(self);
+    if (current_area == NULL) {
+        return true;
+    }
+    displayio_epaperdisplay_start_refresh(self);
+    while (current_area != NULL) {
+        displayio_epaperdisplay_refresh_area(self, current_area);
+        current_area = current_area->next;
+    }
+    displayio_epaperdisplay_finish_refresh(self);
+    return true;
+}
+
+void displayio_epaperdisplay_background(displayio_epaperdisplay_obj_t *self) {
+    if (self->refreshing) {
+        bool refresh_done = false;
+        if (self->busy.base.type == &digitalio_digitalinout_type) {
+            bool busy = common_hal_digitalio_digitalinout_get_value(&self->busy);
+            refresh_done = busy != self->busy_state;
+        } else {
+            refresh_done = supervisor_ticks_ms64() - self->core.last_refresh > self->refresh_time;
+        }
+        if (refresh_done) {
+            supervisor_disable_tick();
+            self->refreshing = false;
+            // Run stop sequence but don't wait for busy because busy is set when sleeping.
+            send_command_sequence(self, false, self->stop_sequence, self->stop_sequence_len);
+        }
+    }
+}
+
+bool common_hal_displayio_epaperdisplay_get_busy(displayio_epaperdisplay_obj_t *self) {
+    displayio_epaperdisplay_background(self);
+    return self->refreshing;
+}
+
+void release_epaperdisplay(displayio_epaperdisplay_obj_t *self) {
+    if (self->refreshing) {
+        wait_for_busy(self);
+        supervisor_disable_tick();
+        self->refreshing = false;
+        // Run stop sequence but don't wait for busy because busy is set when sleeping.
+        send_command_sequence(self, false, self->stop_sequence, self->stop_sequence_len);
+    }
+
+    release_display_core(&self->core);
+    if (self->busy.base.type == &digitalio_digitalinout_type) {
+        common_hal_digitalio_digitalinout_deinit(&self->busy);
+    }
+}
+
+void displayio_epaperdisplay_collect_ptrs(displayio_epaperdisplay_obj_t *self) {
+    displayio_display_core_collect_ptrs(&self->core);
+    gc_collect_ptr((void *)self->start_sequence);
+    gc_collect_ptr((void *)self->stop_sequence);
+}
+
+size_t maybe_refresh_epaperdisplay(void) {
+    for (uint8_t i = 0; i < CIRCUITPY_DISPLAY_LIMIT; i++) {
+        if (displays[i].epaper_display.base.type != &displayio_epaperdisplay_type ||
+            displays[i].epaper_display.core.current_group != &circuitpython_splash) {
+            // Skip regular displays and those not showing the splash.
+            continue;
+        }
+        displayio_epaperdisplay_obj_t *display = &displays[i].epaper_display;
+        size_t time_to_refresh = common_hal_displayio_epaperdisplay_get_time_to_refresh(display);
+        if (time_to_refresh > 0) {
+            return time_to_refresh;
+        }
+        if (common_hal_displayio_epaperdisplay_refresh(display)) {
+            return 0;
+        }
+        // If we could refresh but it failed, then we want to retry.
+        return 1;
+    }
+    // Return 0 if no ePaper displays are available to pretend it was updated.
+    return 0;
+}