sharpmemory: Implement support for Sharp Memory Displays in framebufferio

1 files changed, 282 insertions, 0 deletions

diff --git a/shared-module/sharpdisplay/SharpMemoryFramebuffer.c b/shared-module/sharpdisplay/SharpMemoryFramebuffer.c
new file mode 100644
index 000000000..ac9c22572
--- /dev/null
+++ b/shared-module/sharpdisplay/SharpMemoryFramebuffer.c
@@ -0,0 +1,282 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 Jeff Epler 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 <string.h>
+
+#include "py/gc.h"
+
+#include "shared-bindings/board/__init__.h"
+#include "shared-bindings/microcontroller/Pin.h"
+#include "shared-bindings/sharpdisplay/SharpMemoryFramebuffer.h"
+#include "shared-module/sharpdisplay/SharpMemoryFramebuffer.h"
+
+#include "supervisor/memory.h"
+
+#define SHARPMEM_BIT_WRITECMD_LSB (0x80)
+#define SHARPMEM_BIT_VCOM_LSB (0x40)
+
+static inline void *hybrid_alloc(size_t sz) {
+    if (gc_alloc_possible()) {
+        return m_malloc(sz + sizeof(void*), true);
+    } else {
+        supervisor_allocation *allocation = allocate_memory(align32_size(sz), false);
+        if (!allocation) {
+            return NULL;
+        }
+        memset(allocation->ptr, 0, sz);
+        return allocation->ptr;
+    }
+}
+
+static inline void hybrid_free(void *ptr_in) {
+    supervisor_allocation *allocation = allocation_from_ptr(ptr_in);
+
+    if (allocation) {
+        free_memory(allocation);
+    }
+}
+
+STATIC uint8_t bitrev(uint8_t n) {
+    uint8_t r = 0;
+    for(int i=0;i<8;i++) r |= ((n>>i) & 1)<<(7-i);
+    return r;
+}
+
+int common_hal_sharpdisplay_framebuffer_get_width(sharpdisplay_framebuffer_obj_t *self) {
+    return self->width;
+}
+
+int common_hal_sharpdisplay_framebuffer_get_height(sharpdisplay_framebuffer_obj_t *self) {
+    return self->height;
+}
+
+int common_hal_sharpdisplay_framebuffer_get_row_stride(sharpdisplay_framebuffer_obj_t *self) {
+    return (self->width + 7) / 8 + 2;
+}
+
+int common_hal_sharpdisplay_framebuffer_get_first_pixel_offset(sharpdisplay_framebuffer_obj_t *self) {
+    return 2;
+}
+
+bool common_hal_sharpdisplay_framebuffer_get_reverse_pixels_in_byte(sharpdisplay_framebuffer_obj_t *self) {
+    return true;
+}
+
+bool common_hal_sharpdisplay_framebuffer_get_pixels_in_byte_share_row(sharpdisplay_framebuffer_obj_t *self) {
+    return true;
+}
+
+void common_hal_sharpdisplay_framebuffer_reset(sharpdisplay_framebuffer_obj_t *self) {
+    if (!allocation_from_ptr(self->bufinfo.buf)) {
+        self->bufinfo.buf = NULL;
+    }
+
+    if (self->bus != &self->inline_bus
+#if BOARD_SPI
+        && self->bus != common_hal_board_get_spi()
+#endif
+    ) {
+        memcpy(&self->inline_bus, self->bus, sizeof(busio_spi_obj_t));
+        self->bus = &self->inline_bus;
+    }
+}
+
+void common_hal_sharpdisplay_framebuffer_reconstruct(sharpdisplay_framebuffer_obj_t *self) {
+
+}
+
+void common_hal_sharpdisplay_framebuffer_get_bufinfo(sharpdisplay_framebuffer_obj_t *self, mp_buffer_info_t *bufinfo) {
+    if (!self->bufinfo.buf) {
+        int row_stride = common_hal_sharpdisplay_framebuffer_get_row_stride(self);
+        int height = common_hal_sharpdisplay_framebuffer_get_height(self);
+        self->bufinfo.len = row_stride * height + 2;
+        self->bufinfo.buf = hybrid_alloc(self->bufinfo.len);
+
+        uint8_t *data = self->bufinfo.buf;
+        *data++ = SHARPMEM_BIT_WRITECMD_LSB;
+
+        for(int y=0; y<height; y++) {
+            *data = bitrev(y+1);
+            data += row_stride;
+        }
+        self->full_refresh = true;
+    }
+    *bufinfo = self->bufinfo;
+}
+
+void common_hal_sharpdisplay_framebuffer_deinit(sharpdisplay_framebuffer_obj_t *self) {
+    if (self->base.type != &sharpdisplay_framebuffer_type) {
+        return;
+    }
+
+    if (self->bus == &self->inline_bus) {
+        common_hal_busio_spi_deinit(self->bus);
+    }
+
+    common_hal_reset_pin(self->chip_select.pin);
+
+    hybrid_free(self->bufinfo.buf);
+
+    memset(self, 0, sizeof(*self));
+}
+
+void common_hal_sharpdisplay_framebuffer_construct(sharpdisplay_framebuffer_obj_t *self, busio_spi_obj_t *spi, mcu_pin_obj_t *chip_select, int baudrate, int width, int height) {
+    common_hal_digitalio_digitalinout_construct(&self->chip_select, chip_select);
+    common_hal_digitalio_digitalinout_switch_to_output(&self->chip_select, true, DRIVE_MODE_PUSH_PULL);
+    common_hal_never_reset_pin(chip_select);
+
+    self->bus = spi;
+    common_hal_busio_spi_never_reset(self->bus);
+
+    self->width = width;
+    self->height = height;
+    self->baudrate = baudrate;
+
+    int row_stride = common_hal_sharpdisplay_framebuffer_get_row_stride(self);
+    self->bufinfo.len = row_stride * height + 2;
+    self->bufinfo.buf = gc_alloc(self->bufinfo.len, false, true);
+
+    uint8_t *data = self->bufinfo.buf;
+    *data++ = SHARPMEM_BIT_WRITECMD_LSB;
+
+    for(int y=0; y<self->height; y++) {
+        *data = bitrev(y+1);
+        data += row_stride;
+    }
+    self->full_refresh = true;
+}
+
+void common_hal_sharpdisplay_framebuffer_swapbuffers(sharpdisplay_framebuffer_obj_t *self, uint8_t *dirty_row_bitmask) {
+    // claim SPI bus
+    if (!common_hal_busio_spi_try_lock(self->bus)) {
+        return;
+    }
+    common_hal_busio_spi_configure(self->bus, self->baudrate, 0, 0, 8);
+
+    // set chip select high
+    common_hal_digitalio_digitalinout_set_value(&self->chip_select, true);
+
+    // output the toggling signal
+    uint8_t *data = self->bufinfo.buf;
+    data[0] ^= SHARPMEM_BIT_VCOM_LSB;
+
+#define PARTIAL_UPDATES (1)
+#if PARTIAL_UPDATES
+    common_hal_busio_spi_write(self->bus, data++, 1);
+
+    // output each changed row
+    size_t row_stride = common_hal_sharpdisplay_framebuffer_get_row_stride(self);
+    for(int y=0; y<self->height; y++) {
+        if(self->full_refresh || (dirty_row_bitmask[y/8] & (1 << (y & 7)))) {
+            common_hal_busio_spi_write(self->bus, data, row_stride);
+        }
+        data += row_stride;
+    }
+
+    // output a trailing zero
+    common_hal_busio_spi_write(self->bus, data, 1);
+#else
+    common_hal_busio_spi_write(self->bus, data, self->bufinfo.len);
+#endif
+
+    // set chip select low
+    common_hal_digitalio_digitalinout_set_value(&self->chip_select, false);
+
+    // release SPI bus
+    common_hal_busio_spi_unlock(self->bus);
+
+    self->full_refresh = false;
+}
+
+STATIC void sharpdisplay_framebuffer_deinit(mp_obj_t self_in) {
+    sharpdisplay_framebuffer_obj_t *self = self_in;
+    common_hal_sharpdisplay_framebuffer_deinit(self);
+}
+
+STATIC void sharpdisplay_framebuffer_get_bufinfo(mp_obj_t self_in, mp_buffer_info_t *bufinfo) {
+    sharpdisplay_framebuffer_obj_t *self = self_in;
+    common_hal_sharpdisplay_framebuffer_get_bufinfo(self, bufinfo);
+}
+
+STATIC int sharpdisplay_framebuffer_get_color_depth(mp_obj_t self_in) {
+    return 1;
+}
+
+STATIC int sharpdisplay_framebuffer_get_height(mp_obj_t self_in) {
+    sharpdisplay_framebuffer_obj_t *self = self_in;
+    return common_hal_sharpdisplay_framebuffer_get_height(self);
+}
+
+STATIC int sharpdisplay_framebuffer_get_width(mp_obj_t self_in) {
+    sharpdisplay_framebuffer_obj_t *self = self_in;
+    return common_hal_sharpdisplay_framebuffer_get_width(self);
+}
+
+STATIC int sharpdisplay_framebuffer_get_first_pixel_offset(mp_obj_t self_in) {
+    sharpdisplay_framebuffer_obj_t *self = self_in;
+    return common_hal_sharpdisplay_framebuffer_get_first_pixel_offset(self);
+}
+
+STATIC bool sharpdisplay_framebuffer_get_pixels_in_byte_share_row(mp_obj_t self_in) {
+    sharpdisplay_framebuffer_obj_t *self = self_in;
+    return common_hal_sharpdisplay_framebuffer_get_pixels_in_byte_share_row(self);
+}
+
+STATIC bool sharpdisplay_framebuffer_get_reverse_pixels_in_byte(mp_obj_t self_in) {
+    sharpdisplay_framebuffer_obj_t *self = self_in;
+    return common_hal_sharpdisplay_framebuffer_get_reverse_pixels_in_byte(self);
+}
+
+STATIC int sharpdisplay_framebuffer_get_row_stride(mp_obj_t self_in) {
+    sharpdisplay_framebuffer_obj_t *self = self_in;
+    return common_hal_sharpdisplay_framebuffer_get_row_stride(self);
+}
+
+STATIC void sharpdisplay_framebuffer_swapbuffers(mp_obj_t self_in, uint8_t *dirty_row_bitmask) {
+    sharpdisplay_framebuffer_obj_t *self = self_in;
+    common_hal_sharpdisplay_framebuffer_swapbuffers(self, dirty_row_bitmask);
+}
+
+const framebuffer_p_t sharpdisplay_framebuffer_proto = {
+    MP_PROTO_IMPLEMENT(MP_QSTR_protocol_framebuffer)
+    .deinit = sharpdisplay_framebuffer_deinit,
+    .get_bufinfo = sharpdisplay_framebuffer_get_bufinfo,
+    .get_color_depth = sharpdisplay_framebuffer_get_color_depth,
+    .get_height = sharpdisplay_framebuffer_get_height,
+    .get_width = sharpdisplay_framebuffer_get_width,
+    .swapbuffers = sharpdisplay_framebuffer_swapbuffers,
+
+    .get_first_pixel_offset = sharpdisplay_framebuffer_get_first_pixel_offset,
+    .get_pixels_in_byte_share_row = sharpdisplay_framebuffer_get_pixels_in_byte_share_row,
+    .get_reverse_pixels_in_byte = sharpdisplay_framebuffer_get_reverse_pixels_in_byte,
+    .get_row_stride = sharpdisplay_framebuffer_get_row_stride,
+};
+
+void common_hal_sharpdisplay_framebuffer_collect_ptrs(sharpdisplay_framebuffer_obj_t *self) {
+    gc_collect_ptr(self->framebuffer);
+    gc_collect_ptr(self->bus);
+    gc_collect_ptr(self->bufinfo.buf);
+}