pw_display_driver_st7789/display_driver.cc - pigweed/experimental - Git at Google

 // Copyright 2022 The Pigweed Authors
 //
 // Licensed under the Apache License, Version 2.0 (the "License"); you may not
 // use this file except in compliance with the License. You may obtain a copy of
 // the License at
 //
 //     https://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 // License for the specific language governing permissions and limitations under
 // the License.

 #include "pw_display_driver_st7789/display_driver.h"

 #include <array>
 #include <cstddef>

 #include "pw_digital_io/digital_io.h"
 #include "pw_framebuffer/framebuffer.h"
 #include "pw_spin_delay/delay.h"

 using pw::digital_io::State;
 using pw::framebuffer::Framebuffer;
 using pw::framebuffer::PixelFormat;
 using pw::spi::ChipSelectBehavior;
 using pw::spi::Device;
 using std::array;
 using std::byte;

 namespace pw::display_driver {

 namespace {

 constexpr array<byte, 0> kEmptyArray;

 // ST7789 Display Registers
 // clang-format off
 #define ST7789_SWRESET  0x01
 #define ST7789_TEOFF    0x34
 #define ST7789_TEON     0x35
 #define ST7789_MADCTL   0x36
 #define ST7789_COLMOD   0x3A
 #define ST7789_GCTRL    0xB7
 #define ST7789_VCOMS    0xBB
 #define ST7789_LCMCTRL  0xC0
 #define ST7789_VDVVRHEN 0xC2
 #define ST7789_VRHS     0xC3
 #define ST7789_VDVS     0xC4
 #define ST7789_FRCTRL2  0xC6
 #define ST7789_PWCTRL1  0xD0
 #define ST7789_PORCTRL  0xB2
 #define ST7789_GMCTRP1  0xE0
 #define ST7789_GMCTRN1  0xE1
 #define ST7789_INVOFF   0x20
 #define ST7789_SLPOUT   0x11
 #define ST7789_DISPON   0x29
 #define ST7789_GAMSET   0x26
 #define ST7789_DISPOFF  0x28
 #define ST7789_RAMWR    0x2C
 #define ST7789_INVON    0x21
 #define ST7789_CASET    0x2A
 #define ST7789_RASET    0x2B

 // MADCTL Bits (See page 215: MADCTL (36h): Memory Data Access Control)
 #define ST7789_MADCTL_ROW_ORDER   0b10000000
 #define ST7789_MADCTL_COL_ORDER   0b01000000
 #define ST7789_MADCTL_SWAP_XY     0b00100000
 #define ST7789_MADCTL_SCAN_ORDER  0b00010000
 #define ST7789_MADCTL_RGB_BGR     0b00001000
 #define ST7789_MADCTL_HORIZ_ORDER 0b00000100
 // clang-format on

 constexpr uint8_t HighByte(uint16_t val) { return val >> 8; }

 constexpr uint8_t LowByte(uint16_t val) { return val & 0xff; }

 }  // namespace

 DisplayDriverST7789::DisplayDriverST7789(const Config& config)
     : config_(config) {}

 void DisplayDriverST7789::SetMode(Mode mode) {
   // Set the D/CX pin to indicate data or command values.
   if (mode == Mode::kData) {
     config_.data_cmd_gpio.SetState(State::kActive);
   } else {
     config_.data_cmd_gpio.SetState(State::kInactive);
   }
 }

 Status DisplayDriverST7789::WriteCommand(Device::Transaction& transaction,
                                          const Command& command) {
   SetMode(Mode::kCommand);
   byte buff[1]{static_cast<byte>(command.command)};
   auto s = transaction.Write(buff);
   if (!s.ok())
     return s;

   SetMode(Mode::kData);
   if (command.command_data.empty()) {
     return OkStatus();
   }
   return transaction.Write(command.command_data);
 }

 Status DisplayDriverST7789::Init() {
   auto transaction = config_.spi_device_8_bit.StartTransaction(
       ChipSelectBehavior::kPerWriteRead);

   WriteCommand(transaction, {ST7789_SWRESET, kEmptyArray});  // Software reset
   pw::spin_delay::WaitMillis(150);

   WriteCommand(transaction, {ST7789_TEON, kEmptyArray});
   WriteCommand(transaction, {ST7789_COLMOD, array<byte, 1>{byte{0x05}}});

   WriteCommand(transaction,
                {ST7789_PORCTRL,
                 array<byte, 5>{
                     byte{0x0c},
                     byte{0x0c},
                     byte{0x00},
                     byte{0x33},
                     byte{0x33},
                 }});
   WriteCommand(transaction, {ST7789_LCMCTRL, array<byte, 1>{byte{0x2c}}});
   WriteCommand(transaction, {ST7789_VDVVRHEN, array<byte, 1>{byte{0x01}}});
   WriteCommand(transaction, {ST7789_VRHS, array<byte, 1>{byte{0x12}}});
   WriteCommand(transaction, {ST7789_VDVS, array<byte, 1>{byte{0x20}}});
   WriteCommand(transaction,
                {ST7789_PWCTRL1,
                 array<byte, 2>{
                     byte{0xa4},
                     byte{0xa1},
                 }});
   WriteCommand(transaction, {ST7789_FRCTRL2, array<byte, 1>{byte{0x0f}}});

   WriteCommand(transaction, {ST7789_INVON, kEmptyArray});
   WriteCommand(transaction, {ST7789_SLPOUT, kEmptyArray});
   WriteCommand(transaction, {ST7789_DISPON, kEmptyArray});

   // Landscape drawing Column Address Set
   const uint16_t kMaxColumn = config_.screen_width - 1;
   WriteCommand(transaction,
                {ST7789_CASET,
                 array<byte, 4>{
                     byte{0x0},
                     byte{0x0},
                     byte{static_cast<uint8_t>(kMaxColumn >> 8)},
                     byte{static_cast<uint8_t>(kMaxColumn & 0xff)},
                 }});

   // Page Address Set
   const uint16_t kMaxRow = config_.screen_height - 1;
   WriteCommand(transaction,
                {ST7789_RASET,
                 array<byte, 4>{
                     byte{0x0},
                     byte{0x0},
                     byte{static_cast<uint8_t>(kMaxRow >> 8)},
                     byte{static_cast<uint8_t>(kMaxRow & 0xff)},
                 }});

   uint8_t madctl = 0;
   bool rotate_180 = false;

   if (config_.screen_width == 240 && config_.screen_height == 240) {
     // TODO: Figure out 240x240 square display MADCTL values for rotation.
     madctl = ST7789_MADCTL_HORIZ_ORDER;
   } else if (config_.screen_width == 320 && config_.screen_height == 240) {
     madctl = ST7789_MADCTL_COL_ORDER;
     if (rotate_180)
       madctl = ST7789_MADCTL_ROW_ORDER;

     madctl |= ST7789_MADCTL_SWAP_XY | ST7789_MADCTL_SCAN_ORDER;
   }

   WriteCommand(transaction, {ST7789_MADCTL, array<byte, 1>{byte{madctl}}});

   pw::spin_delay::WaitMillis(50);

   return OkStatus();
 }

 void DisplayDriverST7789::WriteFramebuffer(Framebuffer frame_buffer,
                                            WriteCallback write_callback) {
   PW_ASSERT(frame_buffer.pixel_format() == PixelFormat::RGB565);
   if (config_.pixel_pusher) {
     // Write the pixel data.
     config_.pixel_pusher->WriteFramebuffer(std::move(frame_buffer),
                                            std::move(write_callback));
     return;
   }

   // Write the frame_buffer using pw_spi.
   // Let controller know a write is coming.
   Status s;
   {
     auto transaction = config_.spi_device_8_bit.StartTransaction(
         ChipSelectBehavior::kPerWriteRead);
     s = WriteCommand(transaction, {ST7789_RAMWR, kEmptyArray});
     if (!s.ok()) {
       write_callback(std::move(frame_buffer), s);
       return;
     }
   }

   // Write the pixel data.
   auto transaction = config_.spi_device_16_bit.StartTransaction(
       ChipSelectBehavior::kPerWriteRead);
   const uint16_t* fb_data = static_cast<const uint16_t*>(frame_buffer.data());
   const int num_pixels = frame_buffer.size().width * frame_buffer.size().height;
   s = transaction.Write(
       ConstByteSpan(reinterpret_cast<const byte*>(fb_data), num_pixels));
   write_callback(std::move(frame_buffer), s);
 }

 Status DisplayDriverST7789::WriteRow(span<uint16_t> row_pixels,
                                      uint16_t row_idx,
                                      uint16_t col_idx) {
   {
     // Let controller know a write is coming.
     auto transaction = config_.spi_device_8_bit.StartTransaction(
         ChipSelectBehavior::kPerWriteRead);
     // Landscape drawing Column Address Set
     const uint16_t max_col_idx =
         std::max(config_.screen_width - 1,
                  col_idx + static_cast<int>(row_pixels.size()));
     WriteCommand(transaction,
                  {ST7789_CASET,
                   std::array<std::byte, 4>{
                       std::byte{HighByte(col_idx)},
                       std::byte{LowByte(col_idx)},
                       std::byte{HighByte(max_col_idx)},
                       std::byte{LowByte(max_col_idx)},
                   }});

     // Page Address Set
     uint16_t max_row_idx = row_idx;
     WriteCommand(transaction,
                  {ST7789_RASET,
                   std::array<std::byte, 4>{
                       std::byte{HighByte(row_idx)},
                       std::byte{LowByte(row_idx)},
                       std::byte{HighByte(max_row_idx)},
                       std::byte{LowByte(max_row_idx)},
                   }});
     PW_TRY(WriteCommand(transaction, {ST7789_RAMWR, kEmptyArray}));
   }

   auto transaction = config_.spi_device_16_bit.StartTransaction(
       ChipSelectBehavior::kPerTransaction);
   return transaction.Write(
       ConstByteSpan(reinterpret_cast<const std::byte*>(row_pixels.data()),
                     row_pixels.size()));
 }

 Status DisplayDriverST7789::Reset() {
   if (!config_.reset_gpio)
     return Status::Unavailable();
   auto s = config_.reset_gpio->SetStateInactive();
   if (!s.ok())
     return s;
   pw::spin_delay::WaitMillis(100);
   s = config_.reset_gpio->SetStateActive();
   pw::spin_delay::WaitMillis(100);
   return s;
 }

 bool DisplayDriverST7789::SupportsResize() const {
   return config_.pixel_pusher != nullptr &&
          config_.pixel_pusher->SupportsResize();
 }

 }  // namespace pw::display_driver
	// Copyright 2022 The Pigweed Authors
	//
	// Licensed under the Apache License, Version 2.0 (the "License"); you may not
	// use this file except in compliance with the License. You may obtain a copy of
	// the License at
	//
	// https://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing, software
	// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
	// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
	// License for the specific language governing permissions and limitations under
	// the License.

	#include "pw_display_driver_st7789/display_driver.h"

	#include <array>
	#include <cstddef>

	#include "pw_digital_io/digital_io.h"
	#include "pw_framebuffer/framebuffer.h"
	#include "pw_spin_delay/delay.h"

	using pw::digital_io::State;
	using pw::framebuffer::Framebuffer;
	using pw::framebuffer::PixelFormat;
	using pw::spi::ChipSelectBehavior;
	using pw::spi::Device;
	using std::array;
	using std::byte;

	namespace pw::display_driver {

	namespace {

	constexpr array<byte, 0> kEmptyArray;

	// ST7789 Display Registers
	// clang-format off
	#define ST7789_SWRESET 0x01
	#define ST7789_TEOFF 0x34
	#define ST7789_TEON 0x35
	#define ST7789_MADCTL 0x36
	#define ST7789_COLMOD 0x3A
	#define ST7789_GCTRL 0xB7
	#define ST7789_VCOMS 0xBB
	#define ST7789_LCMCTRL 0xC0
	#define ST7789_VDVVRHEN 0xC2
	#define ST7789_VRHS 0xC3
	#define ST7789_VDVS 0xC4
	#define ST7789_FRCTRL2 0xC6
	#define ST7789_PWCTRL1 0xD0
	#define ST7789_PORCTRL 0xB2
	#define ST7789_GMCTRP1 0xE0
	#define ST7789_GMCTRN1 0xE1
	#define ST7789_INVOFF 0x20
	#define ST7789_SLPOUT 0x11
	#define ST7789_DISPON 0x29
	#define ST7789_GAMSET 0x26
	#define ST7789_DISPOFF 0x28
	#define ST7789_RAMWR 0x2C
	#define ST7789_INVON 0x21
	#define ST7789_CASET 0x2A
	#define ST7789_RASET 0x2B

	// MADCTL Bits (See page 215: MADCTL (36h): Memory Data Access Control)
	#define ST7789_MADCTL_ROW_ORDER 0b10000000
	#define ST7789_MADCTL_COL_ORDER 0b01000000
	#define ST7789_MADCTL_SWAP_XY 0b00100000
	#define ST7789_MADCTL_SCAN_ORDER 0b00010000
	#define ST7789_MADCTL_RGB_BGR 0b00001000
	#define ST7789_MADCTL_HORIZ_ORDER 0b00000100
	// clang-format on

	constexpr uint8_t HighByte(uint16_t val) { return val >> 8; }

	constexpr uint8_t LowByte(uint16_t val) { return val & 0xff; }

	} // namespace

	DisplayDriverST7789::DisplayDriverST7789(const Config& config)
	: config_(config) {}

	void DisplayDriverST7789::SetMode(Mode mode) {
	// Set the D/CX pin to indicate data or command values.
	if (mode == Mode::kData) {
	config_.data_cmd_gpio.SetState(State::kActive);
	} else {
	config_.data_cmd_gpio.SetState(State::kInactive);
	}
	}

	Status DisplayDriverST7789::WriteCommand(Device::Transaction& transaction,
	const Command& command) {
	SetMode(Mode::kCommand);
	byte buff[1]{static_cast<byte>(command.command)};
	auto s = transaction.Write(buff);
	if (!s.ok())
	return s;

	SetMode(Mode::kData);
	if (command.command_data.empty()) {
	return OkStatus();
	}
	return transaction.Write(command.command_data);
	}

	Status DisplayDriverST7789::Init() {
	auto transaction = config_.spi_device_8_bit.StartTransaction(
	ChipSelectBehavior::kPerWriteRead);

	WriteCommand(transaction, {ST7789_SWRESET, kEmptyArray}); // Software reset
	pw::spin_delay::WaitMillis(150);

	WriteCommand(transaction, {ST7789_TEON, kEmptyArray});
	WriteCommand(transaction, {ST7789_COLMOD, array<byte, 1>{byte{0x05}}});

	WriteCommand(transaction,
	{ST7789_PORCTRL,
	array<byte, 5>{
	byte{0x0c},
	byte{0x0c},
	byte{0x00},
	byte{0x33},
	byte{0x33},
	}});
	WriteCommand(transaction, {ST7789_LCMCTRL, array<byte, 1>{byte{0x2c}}});
	WriteCommand(transaction, {ST7789_VDVVRHEN, array<byte, 1>{byte{0x01}}});
	WriteCommand(transaction, {ST7789_VRHS, array<byte, 1>{byte{0x12}}});
	WriteCommand(transaction, {ST7789_VDVS, array<byte, 1>{byte{0x20}}});
	WriteCommand(transaction,
	{ST7789_PWCTRL1,
	array<byte, 2>{
	byte{0xa4},
	byte{0xa1},
	}});
	WriteCommand(transaction, {ST7789_FRCTRL2, array<byte, 1>{byte{0x0f}}});

	WriteCommand(transaction, {ST7789_INVON, kEmptyArray});
	WriteCommand(transaction, {ST7789_SLPOUT, kEmptyArray});
	WriteCommand(transaction, {ST7789_DISPON, kEmptyArray});

	// Landscape drawing Column Address Set
	const uint16_t kMaxColumn = config_.screen_width - 1;
	WriteCommand(transaction,
	{ST7789_CASET,
	array<byte, 4>{
	byte{0x0},
	byte{0x0},
	byte{static_cast<uint8_t>(kMaxColumn >> 8)},
	byte{static_cast<uint8_t>(kMaxColumn & 0xff)},
	}});

	// Page Address Set
	const uint16_t kMaxRow = config_.screen_height - 1;
	WriteCommand(transaction,
	{ST7789_RASET,
	array<byte, 4>{
	byte{0x0},
	byte{0x0},
	byte{static_cast<uint8_t>(kMaxRow >> 8)},
	byte{static_cast<uint8_t>(kMaxRow & 0xff)},
	}});

	uint8_t madctl = 0;
	bool rotate_180 = false;

	if (config_.screen_width == 240 && config_.screen_height == 240) {
	// TODO: Figure out 240x240 square display MADCTL values for rotation.
	madctl = ST7789_MADCTL_HORIZ_ORDER;
	} else if (config_.screen_width == 320 && config_.screen_height == 240) {
	madctl = ST7789_MADCTL_COL_ORDER;
	if (rotate_180)
	madctl = ST7789_MADCTL_ROW_ORDER;

	madctl \|= ST7789_MADCTL_SWAP_XY \| ST7789_MADCTL_SCAN_ORDER;
	}

	WriteCommand(transaction, {ST7789_MADCTL, array<byte, 1>{byte{madctl}}});

	pw::spin_delay::WaitMillis(50);

	return OkStatus();
	}

	void DisplayDriverST7789::WriteFramebuffer(Framebuffer frame_buffer,
	WriteCallback write_callback) {
	PW_ASSERT(frame_buffer.pixel_format() == PixelFormat::RGB565);
	if (config_.pixel_pusher) {
	// Write the pixel data.
	config_.pixel_pusher->WriteFramebuffer(std::move(frame_buffer),
	std::move(write_callback));
	return;
	}

	// Write the frame_buffer using pw_spi.
	// Let controller know a write is coming.
	Status s;
	{
	auto transaction = config_.spi_device_8_bit.StartTransaction(
	ChipSelectBehavior::kPerWriteRead);
	s = WriteCommand(transaction, {ST7789_RAMWR, kEmptyArray});
	if (!s.ok()) {
	write_callback(std::move(frame_buffer), s);
	return;
	}
	}

	// Write the pixel data.
	auto transaction = config_.spi_device_16_bit.StartTransaction(
	ChipSelectBehavior::kPerWriteRead);
	const uint16_t* fb_data = static_cast<const uint16_t*>(frame_buffer.data());
	const int num_pixels = frame_buffer.size().width * frame_buffer.size().height;
	s = transaction.Write(
	ConstByteSpan(reinterpret_cast<const byte*>(fb_data), num_pixels));
	write_callback(std::move(frame_buffer), s);
	}

	Status DisplayDriverST7789::WriteRow(span<uint16_t> row_pixels,
	uint16_t row_idx,
	uint16_t col_idx) {
	{
	// Let controller know a write is coming.
	auto transaction = config_.spi_device_8_bit.StartTransaction(
	ChipSelectBehavior::kPerWriteRead);
	// Landscape drawing Column Address Set
	const uint16_t max_col_idx =
	std::max(config_.screen_width - 1,
	col_idx + static_cast<int>(row_pixels.size()));
	WriteCommand(transaction,
	{ST7789_CASET,
	std::array<std::byte, 4>{
	std::byte{HighByte(col_idx)},
	std::byte{LowByte(col_idx)},
	std::byte{HighByte(max_col_idx)},
	std::byte{LowByte(max_col_idx)},
	}});

	// Page Address Set
	uint16_t max_row_idx = row_idx;
	WriteCommand(transaction,
	{ST7789_RASET,
	std::array<std::byte, 4>{
	std::byte{HighByte(row_idx)},
	std::byte{LowByte(row_idx)},
	std::byte{HighByte(max_row_idx)},
	std::byte{LowByte(max_row_idx)},
	}});
	PW_TRY(WriteCommand(transaction, {ST7789_RAMWR, kEmptyArray}));
	}

	auto transaction = config_.spi_device_16_bit.StartTransaction(
	ChipSelectBehavior::kPerTransaction);
	return transaction.Write(
	ConstByteSpan(reinterpret_cast<const std::byte*>(row_pixels.data()),
	row_pixels.size()));
	}

	Status DisplayDriverST7789::Reset() {
	if (!config_.reset_gpio)
	return Status::Unavailable();
	auto s = config_.reset_gpio->SetStateInactive();
	if (!s.ok())
	return s;
	pw::spin_delay::WaitMillis(100);
	s = config_.reset_gpio->SetStateActive();
	pw::spin_delay::WaitMillis(100);
	return s;
	}

	bool DisplayDriverST7789::SupportsResize() const {
	return config_.pixel_pusher != nullptr &&
	config_.pixel_pusher->SupportsResize();
	}

	} // namespace pw::display_driver