esp-idf/components/esp_lcd/i80/esp_lcd_panel_io_i2s.c

843 lines
39 KiB
C

/*
* SPDX-FileCopyrightText: 2021-2024 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: Apache-2.0
*/
/////////////////////////////////////////////////////////////////////////////////////////////////////////////
// Although we're manipulating I2S peripheral (on esp32/s2 target), it has nothing to do with the AUDIO BUS.
// In fact, we're simulating the Intel 8080 bus with I2S peripheral, in a special parallel mode.
/////////////////////////////////////////////////////////////////////////////////////////////////////////////
#include <stdlib.h>
#include <string.h>
#include <sys/cdefs.h>
#include <sys/param.h>
#include <sys/queue.h>
#include "sdkconfig.h"
#if CONFIG_LCD_ENABLE_DEBUG_LOG
// The local log level must be defined before including esp_log.h
// Set the maximum log level for this source file
#define LOG_LOCAL_LEVEL ESP_LOG_DEBUG
#endif
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/queue.h"
#include "esp_attr.h"
#include "esp_check.h"
#include "esp_intr_alloc.h"
#include "esp_heap_caps.h"
#include "esp_pm.h"
#include "esp_lcd_panel_io_interface.h"
#include "esp_lcd_panel_io.h"
#include "esp_lcd_common.h"
#include "esp_rom_gpio.h"
#include "soc/soc_caps.h"
#include "hal/gpio_hal.h"
#include "driver/gpio.h"
#include "esp_clk_tree.h"
#include "esp_private/periph_ctrl.h"
#include "esp_private/i2s_platform.h"
#include "esp_private/gdma_link.h"
#include "soc/lcd_periph.h"
#include "hal/i2s_hal.h"
#include "hal/i2s_ll.h"
#include "hal/i2s_types.h"
// the DMA descriptor used by esp32 and esp32s2, each descriptor can carry 4095 bytes at most
#define LCD_DMA_DESCRIPTOR_BUFFER_MAX_SIZE 4095
static const char *TAG = "lcd_panel.io.i80";
typedef struct esp_lcd_i80_bus_t esp_lcd_i80_bus_t;
typedef struct lcd_panel_io_i80_t lcd_panel_io_i80_t;
typedef struct lcd_i80_trans_descriptor_t lcd_i80_trans_descriptor_t;
static esp_err_t panel_io_i80_tx_param(esp_lcd_panel_io_t *io, int lcd_cmd, const void *param, size_t param_size);
static esp_err_t panel_io_i80_tx_color(esp_lcd_panel_io_t *io, int lcd_cmd, const void *color, size_t color_size);
static esp_err_t panel_io_i80_del(esp_lcd_panel_io_t *io);
static esp_err_t i2s_lcd_select_periph_clock(esp_lcd_i80_bus_handle_t bus, lcd_clock_source_t src);
static esp_err_t i2s_lcd_init_dma_link(esp_lcd_i80_bus_handle_t bus);
static esp_err_t i2s_lcd_configure_gpio(esp_lcd_i80_bus_handle_t bus, const esp_lcd_i80_bus_config_t *bus_config);
static void i2s_lcd_trigger_quick_trans_done_event(esp_lcd_i80_bus_handle_t bus);
static void lcd_i80_switch_devices(lcd_panel_io_i80_t *cur_device, lcd_panel_io_i80_t *next_device);
static void lcd_default_isr_handler(void *args);
static esp_err_t panel_io_i80_register_event_callbacks(esp_lcd_panel_io_handle_t io, const esp_lcd_panel_io_callbacks_t *cbs, void *user_ctx);
struct esp_lcd_i80_bus_t {
int bus_id; // Bus ID, index from 0
portMUX_TYPE spinlock; // spinlock used to protect i80 bus members(hal, device_list, cur_trans)
i2s_hal_context_t hal; // Hal object
size_t bus_width; // Number of data lines
int dc_gpio_num; // GPIO used for DC line
int wr_gpio_num; // GPIO used for WR line
intr_handle_t intr; // LCD peripheral interrupt handle
esp_pm_lock_handle_t pm_lock; // lock APB frequency when necessary
size_t num_dma_nodes; // Number of DMA descriptors
gdma_link_list_handle_t dma_link; // DMA link list handle
uint8_t *format_buffer;// The driver allocates an internal buffer for DMA to do data format transformer
unsigned long resolution_hz; // LCD_CLK resolution, determined by selected clock source
lcd_i80_trans_descriptor_t *cur_trans; // Current transaction
lcd_panel_io_i80_t *cur_device; // Current working device
LIST_HEAD(i80_device_list, lcd_panel_io_i80_t) device_list; // Head of i80 device list
struct {
unsigned int exclusive: 1; // Indicate whether the I80 bus is owned by one device (whose CS GPIO is not assigned) exclusively
} flags;
};
struct lcd_i80_trans_descriptor_t {
lcd_panel_io_i80_t *i80_device; // i80 device issuing this transaction
const void *data; // Data buffer
uint32_t data_length; // Data buffer size
esp_lcd_panel_io_color_trans_done_cb_t trans_done_cb; // transaction done callback
void *user_ctx; // private data used by trans_done_cb
struct {
unsigned int dc_level: 1; // Level of DC line for this transaction
} flags;
};
struct lcd_panel_io_i80_t {
esp_lcd_panel_io_t base; // Base class of generic lcd panel io
esp_lcd_i80_bus_t *bus; // Which bus the device is attached to
int cs_gpio_num; // GPIO used for CS line
uint32_t pclk_hz; // PCLK clock frequency
size_t clock_prescale; // Prescaler coefficient, determined by user's configured PCLK frequency
QueueHandle_t trans_queue; // Transaction queue, transactions in this queue are pending for scheduler to dispatch
QueueHandle_t done_queue; // Transaction done queue, transactions in this queue are finished but not recycled by the caller
size_t queue_size; // Size of transaction queue
size_t num_trans_inflight; // Number of transactions that are undergoing (the descriptor not recycled yet)
int lcd_cmd_bits; // Bit width of LCD command
int lcd_param_bits; // Bit width of LCD parameter
void *user_ctx; // private data used when transfer color data
esp_lcd_panel_io_color_trans_done_cb_t on_color_trans_done; // color data trans done callback
LIST_ENTRY(lcd_panel_io_i80_t) device_list_entry; // Entry of i80 device list
struct {
unsigned int dc_cmd_level: 1; // Level of DC line in CMD phase
unsigned int dc_data_level: 1; // Level of DC line in DATA phase
} dc_levels;
struct {
unsigned int cs_active_high: 1; // Whether the CS line is active on high level
unsigned int swap_color_bytes: 1; // Swap adjacent two data bytes before sending out
unsigned int pclk_idle_low: 1; // The WR line keeps at low level in IDLE phase
} flags;
lcd_i80_trans_descriptor_t trans_pool[]; // Transaction pool
};
esp_err_t esp_lcd_new_i80_bus(const esp_lcd_i80_bus_config_t *bus_config, esp_lcd_i80_bus_handle_t *ret_bus)
{
#if CONFIG_LCD_ENABLE_DEBUG_LOG
esp_log_level_set(TAG, ESP_LOG_DEBUG);
#endif
esp_err_t ret = ESP_OK;
esp_lcd_i80_bus_t *bus = NULL;
ESP_GOTO_ON_FALSE(bus_config && ret_bus, ESP_ERR_INVALID_ARG, err, TAG, "invalid argument");
// although I2S bus supports up to 24 parallel data lines, we restrict users to only use 8 or 16 bit width
ESP_GOTO_ON_FALSE(bus_config->bus_width == 8 || bus_config->bus_width == 16, ESP_ERR_INVALID_ARG, err,
TAG, "invalid bus width:%d", bus_config->bus_width);
size_t max_transfer_bytes = (bus_config->max_transfer_bytes + 3) & ~0x03; // align up to 4 bytes
#if SOC_I2S_TRANS_SIZE_ALIGN_WORD
// double the size of the internal DMA buffer if bus_width is 8,
// because one I2S FIFO (4 bytes) will only contain two bytes of valid data
max_transfer_bytes = max_transfer_bytes * 16 / bus_config->bus_width + 4;
#endif
// allocate i80 bus memory
bus = heap_caps_calloc(1, sizeof(esp_lcd_i80_bus_t), LCD_I80_MEM_ALLOC_CAPS);
ESP_GOTO_ON_FALSE(bus, ESP_ERR_NO_MEM, err, TAG, "no mem for i80 bus");
size_t num_dma_nodes = max_transfer_bytes / LCD_DMA_DESCRIPTOR_BUFFER_MAX_SIZE + 1;
// create DMA link list
gdma_link_list_config_t dma_link_config = {
.buffer_alignment = 1, // no special buffer alignment for LCD TX buffer
.item_alignment = 4, // 4 bytes alignment for each DMA descriptor
.num_items = num_dma_nodes,
.flags = {
.check_owner = true,
},
};
ESP_GOTO_ON_ERROR(gdma_new_link_list(&dma_link_config, &bus->dma_link), err, TAG, "create DMA link list failed");
bus->bus_id = -1;
bus->num_dma_nodes = num_dma_nodes;
#if SOC_I2S_TRANS_SIZE_ALIGN_WORD
// transform format for LCD commands, parameters and color data, so we need a big buffer
bus->format_buffer = heap_caps_calloc(1, max_transfer_bytes, MALLOC_CAP_INTERNAL | MALLOC_CAP_8BIT | MALLOC_CAP_DMA);
#else
// only transform format for LCD parameters, buffer size depends on specific LCD, set at compile time
bus->format_buffer = heap_caps_calloc(1, LCD_I80_IO_FORMAT_BUF_SIZE, MALLOC_CAP_INTERNAL | MALLOC_CAP_8BIT | MALLOC_CAP_DMA);
#endif // SOC_I2S_TRANS_SIZE_ALIGN_WORD
ESP_GOTO_ON_FALSE(bus->format_buffer, ESP_ERR_NO_MEM, err, TAG, "no mem for format buffer");
// LCD mode can't work with other modes at the same time, we need to register the driver object to the I2S platform
int bus_id = -1;
for (int i = 0; i < SOC_LCD_I80_BUSES; i++) {
if (i2s_platform_acquire_occupation(I2S_CTLR_HP, i, "esp_lcd_panel_io_i2s") == ESP_OK) {
bus_id = i;
break;
}
}
ESP_GOTO_ON_FALSE(bus_id != -1, ESP_ERR_NOT_FOUND, err, TAG, "no free i80 bus slot");
bus->bus_id = bus_id;
// initialize HAL layer
i2s_hal_init(&bus->hal, bus->bus_id);
// set peripheral clock resolution
ret = i2s_lcd_select_periph_clock(bus, bus_config->clk_src);
ESP_GOTO_ON_ERROR(ret, err, TAG, "select periph clock failed");
// reset peripheral, DMA channel and FIFO
i2s_ll_tx_reset(bus->hal.dev);
i2s_ll_tx_reset_dma(bus->hal.dev);
i2s_ll_tx_reset_fifo(bus->hal.dev);
// install interrupt service, (I2S LCD mode only uses the "TX Unit", which leaves "RX Unit" for other purpose)
// So the interrupt should also be able to share with other functionality
int isr_flags = LCD_I80_INTR_ALLOC_FLAGS | ESP_INTR_FLAG_SHARED | ESP_INTR_FLAG_LOWMED;
ret = esp_intr_alloc_intrstatus(lcd_periph_i2s_signals.buses[bus->bus_id].irq_id, isr_flags,
(uint32_t)i2s_ll_get_intr_status_reg(bus->hal.dev),
I2S_LL_EVENT_TX_EOF, lcd_default_isr_handler, bus, &bus->intr);
ESP_GOTO_ON_ERROR(ret, err, TAG, "install interrupt failed");
i2s_ll_enable_intr(bus->hal.dev, I2S_LL_EVENT_TX_EOF, false); // disable interrupt temporarily
i2s_ll_clear_intr_status(bus->hal.dev, I2S_LL_EVENT_TX_EOF); // clear pending interrupt
// initialize DMA link
i2s_lcd_init_dma_link(bus);
// enable I2S LCD master mode (refer to I2S TRM)
i2s_ll_enable_lcd(bus->hal.dev, true);
i2s_ll_tx_stop_on_fifo_empty(bus->hal.dev, true);
i2s_ll_tx_set_slave_mod(bus->hal.dev, false);
i2s_ll_tx_set_bits_mod(bus->hal.dev, bus_config->bus_width);
i2s_ll_tx_select_std_slot(bus->hal.dev, I2S_STD_SLOT_BOTH, true); // copy mono
bus->bus_width = bus_config->bus_width;
i2s_ll_tx_enable_right_first(bus->hal.dev, true);
#if SOC_I2S_SUPPORTS_DMA_EQUAL
i2s_ll_tx_enable_dma_equal(bus->hal.dev, true);
#endif
// enable trans done interrupt
i2s_ll_enable_intr(bus->hal.dev, I2S_LL_EVENT_TX_EOF, true);
// trigger a quick "trans done" event, and wait for the interrupt line goes active
// this could ensure we go into ISR handler next time we call `esp_intr_enable`
i2s_lcd_trigger_quick_trans_done_event(bus);
// configure GPIO
ret = i2s_lcd_configure_gpio(bus, bus_config);
ESP_GOTO_ON_ERROR(ret, err, TAG, "configure GPIO failed");
// fill other i80 bus runtime parameters
LIST_INIT(&bus->device_list); // initialize device list head
bus->spinlock = (portMUX_TYPE)portMUX_INITIALIZER_UNLOCKED;
bus->dc_gpio_num = bus_config->dc_gpio_num;
bus->wr_gpio_num = bus_config->wr_gpio_num;
*ret_bus = bus;
ESP_LOGD(TAG, "new i80 bus(%d) @%p, %zu dma nodes, resolution %luHz", bus->bus_id, bus, num_dma_nodes, bus->resolution_hz);
return ESP_OK;
err:
if (bus) {
if (bus->dma_link) {
gdma_del_link_list(bus->dma_link);
}
if (bus->intr) {
esp_intr_free(bus->intr);
}
if (bus->bus_id >= 0) {
i2s_platform_release_occupation(I2S_CTLR_HP, bus->bus_id);
}
if (bus->format_buffer) {
free(bus->format_buffer);
}
if (bus->pm_lock) {
esp_pm_lock_delete(bus->pm_lock);
}
free(bus);
}
return ret;
}
esp_err_t esp_lcd_del_i80_bus(esp_lcd_i80_bus_handle_t bus)
{
esp_err_t ret = ESP_OK;
ESP_GOTO_ON_FALSE(bus, ESP_ERR_INVALID_ARG, err, TAG, "invalid argument");
ESP_GOTO_ON_FALSE(LIST_EMPTY(&bus->device_list), ESP_ERR_INVALID_STATE, err, TAG, "device list not empty");
int bus_id = bus->bus_id;
i2s_platform_release_occupation(I2S_CTLR_HP, bus_id);
esp_intr_free(bus->intr);
if (bus->pm_lock) {
esp_pm_lock_delete(bus->pm_lock);
}
free(bus->format_buffer);
gdma_del_link_list(bus->dma_link);
free(bus);
ESP_LOGD(TAG, "del i80 bus(%d)", bus_id);
err:
return ret;
}
esp_err_t esp_lcd_new_panel_io_i80(esp_lcd_i80_bus_handle_t bus, const esp_lcd_panel_io_i80_config_t *io_config, esp_lcd_panel_io_handle_t *ret_io)
{
esp_err_t ret = ESP_OK;
lcd_panel_io_i80_t *i80_device = NULL;
bool bus_exclusive = false;
ESP_GOTO_ON_FALSE(bus && io_config && ret_io, ESP_ERR_INVALID_ARG, err, TAG, "invalid argument");
// check if the bus has been configured as exclusive
portENTER_CRITICAL(&bus->spinlock);
if (!bus->flags.exclusive) {
bus->flags.exclusive = io_config->cs_gpio_num < 0;
} else {
bus_exclusive = true;
}
portEXIT_CRITICAL(&bus->spinlock);
ESP_GOTO_ON_FALSE(!bus_exclusive, ESP_ERR_INVALID_STATE, err, TAG, "bus has been exclusively owned by device");
// because we set the I2S's left channel data same to right channel, so f_pclk = f_i2s/pclk_div/2
uint32_t pclk_prescale = bus->resolution_hz / 2 / io_config->pclk_hz;
ESP_GOTO_ON_FALSE(pclk_prescale > 0 && pclk_prescale <= I2S_LL_BCK_MAX_PRESCALE, ESP_ERR_NOT_SUPPORTED, err, TAG,
"prescaler can't satisfy PCLK clock %"PRIu32"Hz", io_config->pclk_hz);
i80_device = heap_caps_calloc(1, sizeof(lcd_panel_io_i80_t) + io_config->trans_queue_depth * sizeof(lcd_i80_trans_descriptor_t), LCD_I80_MEM_ALLOC_CAPS);
ESP_GOTO_ON_FALSE(i80_device, ESP_ERR_NO_MEM, err, TAG, "no mem for i80 panel io");
// create two queues for i80 device
i80_device->trans_queue = xQueueCreate(io_config->trans_queue_depth, sizeof(lcd_i80_trans_descriptor_t *));
ESP_GOTO_ON_FALSE(i80_device->trans_queue, ESP_ERR_NO_MEM, err, TAG, "create trans queue failed");
i80_device->done_queue = xQueueCreate(io_config->trans_queue_depth, sizeof(lcd_i80_trans_descriptor_t *));
ESP_GOTO_ON_FALSE(i80_device->done_queue, ESP_ERR_NO_MEM, err, TAG, "create done queue failed");
// adding device to list
portENTER_CRITICAL(&bus->spinlock);
LIST_INSERT_HEAD(&bus->device_list, i80_device, device_list_entry);
portEXIT_CRITICAL(&bus->spinlock);
// we don't initialize the i80 bus at the memont, but initialize the bus when start a transaction for a new device
// so save these as i80 device runtime parameters
i80_device->bus = bus;
i80_device->queue_size = io_config->trans_queue_depth;
i80_device->clock_prescale = pclk_prescale;
i80_device->lcd_cmd_bits = io_config->lcd_cmd_bits;
i80_device->lcd_param_bits = io_config->lcd_param_bits;
i80_device->pclk_hz = bus->resolution_hz / pclk_prescale / 2;
i80_device->dc_levels.dc_cmd_level = io_config->dc_levels.dc_cmd_level;
i80_device->dc_levels.dc_data_level = io_config->dc_levels.dc_data_level;
i80_device->cs_gpio_num = io_config->cs_gpio_num;
i80_device->on_color_trans_done = io_config->on_color_trans_done;
i80_device->user_ctx = io_config->user_ctx;
i80_device->flags.cs_active_high = io_config->flags.cs_active_high;
i80_device->flags.swap_color_bytes = io_config->flags.swap_color_bytes;
i80_device->flags.pclk_idle_low = io_config->flags.pclk_idle_low;
// fill panel io function table
i80_device->base.del = panel_io_i80_del;
i80_device->base.tx_param = panel_io_i80_tx_param;
i80_device->base.tx_color = panel_io_i80_tx_color;
i80_device->base.register_event_callbacks = panel_io_i80_register_event_callbacks;
if (io_config->cs_gpio_num >= 0) {
// CS signal is controlled by software
gpio_set_level(io_config->cs_gpio_num, !io_config->flags.cs_active_high); // de-assert by default
gpio_set_direction(io_config->cs_gpio_num, GPIO_MODE_OUTPUT);
gpio_hal_iomux_func_sel(GPIO_PIN_MUX_REG[io_config->cs_gpio_num], PIN_FUNC_GPIO);
}
*ret_io = &(i80_device->base);
ESP_LOGD(TAG, "new i80 lcd panel io @%p on bus(%d), pclk=%"PRIu32"Hz", i80_device, bus->bus_id, i80_device->pclk_hz);
return ESP_OK;
err:
if (i80_device) {
if (i80_device->trans_queue) {
vQueueDelete(i80_device->trans_queue);
}
if (i80_device->done_queue) {
vQueueDelete(i80_device->done_queue);
}
free(i80_device);
}
return ret;
}
void *esp_lcd_i80_alloc_draw_buffer(esp_lcd_panel_io_handle_t io, size_t size, uint32_t caps)
{
ESP_RETURN_ON_FALSE(io, NULL, TAG, "invalid argument");
ESP_RETURN_ON_FALSE((caps & MALLOC_CAP_SPIRAM) == 0, NULL, TAG, "external memory is not supported");
// DMA can only carry internal memory
return heap_caps_aligned_calloc(4, 1, size, MALLOC_CAP_INTERNAL | MALLOC_CAP_8BIT | MALLOC_CAP_DMA);
}
static esp_err_t panel_io_i80_del(esp_lcd_panel_io_t *io)
{
lcd_panel_io_i80_t *i80_device = __containerof(io, lcd_panel_io_i80_t, base);
esp_lcd_i80_bus_t *bus = i80_device->bus;
lcd_i80_trans_descriptor_t *trans_desc = NULL;
size_t num_trans_inflight = i80_device->num_trans_inflight;
// wait all pending transaction to finish
for (size_t i = 0; i < num_trans_inflight; i++) {
ESP_RETURN_ON_FALSE(xQueueReceive(i80_device->done_queue, &trans_desc, portMAX_DELAY) == pdTRUE,
ESP_FAIL, TAG, "recycle inflight transactions failed");
i80_device->num_trans_inflight--;
}
// remove from device list
portENTER_CRITICAL(&bus->spinlock);
LIST_REMOVE(i80_device, device_list_entry);
portEXIT_CRITICAL(&bus->spinlock);
// reset CS GPIO
if (i80_device->cs_gpio_num >= 0) {
gpio_reset_pin(i80_device->cs_gpio_num);
}
ESP_LOGD(TAG, "del i80 lcd panel io @%p", i80_device);
vQueueDelete(i80_device->trans_queue);
vQueueDelete(i80_device->done_queue);
free(i80_device);
return ESP_OK;
}
static esp_err_t panel_io_i80_register_event_callbacks(esp_lcd_panel_io_handle_t io, const esp_lcd_panel_io_callbacks_t *cbs, void *user_ctx)
{
lcd_panel_io_i80_t *i80_device = __containerof(io, lcd_panel_io_i80_t, base);
if (i80_device->on_color_trans_done != NULL) {
ESP_LOGW(TAG, "Callback on_color_trans_done was already set and now it was owerwritten!");
}
i80_device->on_color_trans_done = cbs->on_color_trans_done;
i80_device->user_ctx = user_ctx;
return ESP_OK;
}
static void i2s_lcd_prepare_cmd_buffer(lcd_i80_trans_descriptor_t *trans_desc, const void *cmd)
{
lcd_panel_io_i80_t *i80_device = trans_desc->i80_device;
esp_lcd_i80_bus_t *bus = i80_device->bus;
uint8_t *from = (uint8_t *)cmd;
// LCD is big-endian, e.g. to send command 0x1234, byte 0x12 should appear on the data bus first
// However, the I2S peripheral will send 0x34 first, so we reversed the order below
if (bus->bus_width < i80_device->lcd_cmd_bits) {
int start = 0;
int end = i80_device->lcd_cmd_bits / 8 - 1;
lcd_com_reverse_buffer_bytes(from, start, end);
}
#if SOC_I2S_TRANS_SIZE_ALIGN_WORD
uint8_t *to = bus->format_buffer;
int cmd_cycle = i80_device->lcd_cmd_bits / bus->bus_width;
if (cmd_cycle * bus->bus_width < i80_device->lcd_cmd_bits) {
cmd_cycle++;
}
int bytes_to_copy = MIN(bus->bus_width, i80_device->lcd_cmd_bits) / 8;
int cnt_from = 0;
// format command buffer
for (int i = 0; i < cmd_cycle; i++) {
for (int j = 0; j < bytes_to_copy; j++) {
to[2 + j] = from[cnt_from++];
}
to += 4;
}
trans_desc->data = bus->format_buffer;
trans_desc->data_length = cmd_cycle * 4;
#else
trans_desc->data = cmd;
trans_desc->data_length = MAX(i80_device->lcd_cmd_bits, bus->bus_width) / 8;
#endif
}
static void i2s_lcd_prepare_param_buffer(lcd_i80_trans_descriptor_t *trans_desc, const void *param, size_t param_num)
{
lcd_panel_io_i80_t *i80_device = trans_desc->i80_device;
esp_lcd_i80_bus_t *bus = i80_device->bus;
uint8_t *from = (uint8_t *)param;
int param_size = i80_device->lcd_param_bits / 8;
// LCD is big-endian, e.g. to send param 0x1234, byte 0x12 should appear on the data bus first
// However, the I2S peripheral will send 0x34 first, so we reversed the order below
if (bus->bus_width < i80_device->lcd_param_bits) {
for (size_t i = 0; i < param_num; i++) {
int start = i * param_size;
int end = start + param_size - 1;
lcd_com_reverse_buffer_bytes(from, start, end);
}
}
#if SOC_I2S_TRANS_SIZE_ALIGN_WORD
uint8_t *to = bus->format_buffer;
int param_cycle = i80_device->lcd_param_bits / bus->bus_width;
if (param_cycle * bus->bus_width < i80_device->lcd_param_bits) {
param_cycle++;
}
int ele_cycles = param_cycle * param_num;
int bytes_to_copy = MIN(bus->bus_width, i80_device->lcd_param_bits) / 8;
int cnt_from = 0;
// format parameter buffer
for (int i = 0; i < ele_cycles; i++) {
for (int j = 0; j < bytes_to_copy; j++) {
to[2 + j] = from[cnt_from++];
}
to += 4;
}
trans_desc->data = bus->format_buffer;
trans_desc->data_length = ele_cycles * 4;
#else
uint8_t *to = bus->format_buffer;
uint8_t step = bus->bus_width / 8;
int param_cycle = i80_device->lcd_param_bits / bus->bus_width;
if (param_cycle * bus->bus_width < i80_device->lcd_param_bits) {
param_cycle++;
}
int ele_cycles = param_cycle * param_num;
int bytes_to_copy = MIN(bus->bus_width, i80_device->lcd_param_bits) / 8;
int cnt_from = 0;
// format parameter buffer
for (int i = 0; i < ele_cycles; i++) {
for (int j = 0; j < bytes_to_copy; j++) {
to[j] = from[cnt_from++];
}
to += step;
}
trans_desc->data = bus->format_buffer;
trans_desc->data_length = to - bus->format_buffer;
#endif
}
static void i2s_lcd_prepare_color_buffer(lcd_i80_trans_descriptor_t *trans_desc, const void *color, size_t color_size)
{
#if SOC_I2S_TRANS_SIZE_ALIGN_WORD
lcd_panel_io_i80_t *i80_device = trans_desc->i80_device;
esp_lcd_i80_bus_t *bus = i80_device->bus;
uint8_t *from = (uint8_t *)color;
uint8_t *to = bus->format_buffer;
int bytes_to_copy = bus->bus_width / 8;
int cnt_from = 0;
int first_half = i80_device->flags.swap_color_bytes ? 0 : 2;
int second_half = i80_device->flags.swap_color_bytes ? 2 : 0;
// format color buffer
while (cnt_from < color_size) {
for (int i = 0; i < bytes_to_copy; i++) {
to[first_half + i] = from[cnt_from++];
}
for (int i = 0; i < bytes_to_copy; i++) {
to[second_half + i] = from[cnt_from++];
}
to += 4;
}
trans_desc->data = bus->format_buffer;
trans_desc->data_length = to - bus->format_buffer;
#else
trans_desc->data = color;
trans_desc->data_length = color_size;
#endif
}
static esp_err_t panel_io_i80_tx_param(esp_lcd_panel_io_t *io, int lcd_cmd, const void *param, size_t param_size)
{
lcd_panel_io_i80_t *next_device = __containerof(io, lcd_panel_io_i80_t, base);
esp_lcd_i80_bus_t *bus = next_device->bus;
lcd_panel_io_i80_t *cur_device = bus->cur_device;
lcd_i80_trans_descriptor_t *trans_desc = NULL;
assert(param_size <= (bus->num_dma_nodes * LCD_DMA_DESCRIPTOR_BUFFER_MAX_SIZE) && "parameter bytes too long, enlarge max_transfer_bytes");
assert(param_size <= LCD_I80_IO_FORMAT_BUF_SIZE && "format buffer too small, increase LCD_I80_IO_FORMAT_BUF_SIZE");
size_t num_trans_inflight = next_device->num_trans_inflight;
// before issue a polling transaction, need to wait queued transactions finished
for (size_t i = 0; i < num_trans_inflight; i++) {
ESP_RETURN_ON_FALSE(xQueueReceive(next_device->done_queue, &trans_desc, portMAX_DELAY) == pdTRUE,
ESP_FAIL, TAG, "recycle inflight transactions failed");
next_device->num_trans_inflight--;
}
gdma_buffer_mount_config_t mount_config = {
.flags = {
.mark_eof = true,
.mark_final = true, // singly link list, mark final descriptor
}
};
i2s_ll_clear_intr_status(bus->hal.dev, I2S_LL_EVENT_TX_EOF);
// switch devices if necessary
lcd_i80_switch_devices(cur_device, next_device);
trans_desc = &next_device->trans_pool[0];
trans_desc->i80_device = next_device;
trans_desc->trans_done_cb = NULL; // no callback for command transfer
bus->cur_trans = trans_desc;
#if SOC_I2S_TRANS_SIZE_ALIGN_WORD
// switch to I2S 32bits mode, one WS cycle <=> one I2S FIFO
i2s_ll_tx_set_bits_mod(bus->hal.dev, 32);
#endif
i2s_lcd_prepare_cmd_buffer(trans_desc, &lcd_cmd);
mount_config.buffer = (void *)trans_desc->data;
mount_config.length = trans_desc->data_length;
gdma_link_mount_buffers(bus->dma_link, 0, &mount_config, 1, NULL);
gpio_set_level(bus->dc_gpio_num, next_device->dc_levels.dc_cmd_level);
i2s_ll_tx_stop(bus->hal.dev);
i2s_ll_tx_reset(bus->hal.dev); // reset TX engine first
i2s_ll_start_out_link(bus->hal.dev);
// delay a while, wait for DMA data being feed to I2S FIFO
// in fact, this is only needed when LCD pixel clock is set too high
esp_rom_delay_us(1);
// increase the pm lock reference count before starting a new transaction
if (bus->pm_lock) {
esp_pm_lock_acquire(bus->pm_lock);
}
i2s_ll_tx_start(bus->hal.dev);
// polling the trans done event
while (!(i2s_ll_get_intr_status(bus->hal.dev) & I2S_LL_EVENT_TX_EOF)) {}
// parameter is usually short, using polling mode
if (param && param_size) {
i2s_ll_clear_intr_status(bus->hal.dev, I2S_LL_EVENT_TX_EOF);
i2s_lcd_prepare_param_buffer(trans_desc, param, param_size * 8 / next_device->lcd_param_bits);
mount_config.buffer = (void *)trans_desc->data;
mount_config.length = trans_desc->data_length;
gdma_link_mount_buffers(bus->dma_link, 0, &mount_config, 1, NULL);
gpio_set_level(bus->dc_gpio_num, next_device->dc_levels.dc_data_level);
i2s_ll_tx_stop(bus->hal.dev);
i2s_ll_tx_reset(bus->hal.dev); // reset TX engine first
i2s_ll_start_out_link(bus->hal.dev);
esp_rom_delay_us(1);
i2s_ll_tx_start(bus->hal.dev);
// polling the trans done event, but don't clear the event status
while (!(i2s_ll_get_intr_status(bus->hal.dev) & I2S_LL_EVENT_TX_EOF)) {}
}
// decrease pm lock reference count
if (bus->pm_lock) {
esp_pm_lock_release(bus->pm_lock);
}
bus->cur_trans = NULL;
return ESP_OK;
}
static esp_err_t panel_io_i80_tx_color(esp_lcd_panel_io_t *io, int lcd_cmd, const void *color, size_t color_size)
{
lcd_panel_io_i80_t *next_device = __containerof(io, lcd_panel_io_i80_t, base);
esp_lcd_i80_bus_t *bus = next_device->bus;
lcd_panel_io_i80_t *cur_device = bus->cur_device;
lcd_i80_trans_descriptor_t *trans_desc = NULL;
assert(color_size <= (bus->num_dma_nodes * LCD_DMA_DESCRIPTOR_BUFFER_MAX_SIZE) && "color bytes too long, enlarge max_transfer_bytes");
size_t num_trans_inflight = next_device->num_trans_inflight;
// before issue a polling transaction, need to wait queued transactions finished
for (size_t i = 0; i < num_trans_inflight; i++) {
ESP_RETURN_ON_FALSE(xQueueReceive(next_device->done_queue, &trans_desc, portMAX_DELAY) == pdTRUE,
ESP_FAIL, TAG, "recycle inflight transactions failed");
next_device->num_trans_inflight--;
}
gdma_buffer_mount_config_t mount_config = {
.flags = {
.mark_eof = true,
.mark_final = true, // singly link list, mark final descriptor
}
};
i2s_ll_clear_intr_status(bus->hal.dev, I2S_LL_EVENT_TX_EOF);
// switch devices if necessary
lcd_i80_switch_devices(cur_device, next_device);
trans_desc = &next_device->trans_pool[0];
trans_desc->i80_device = next_device;
trans_desc->trans_done_cb = NULL; // no callback for command transfer
bus->cur_trans = trans_desc;
#if SOC_I2S_TRANS_SIZE_ALIGN_WORD
// switch to I2S 32bits mode, one WS cycle <=> one I2S FIFO
i2s_ll_tx_set_bits_mod(bus->hal.dev, 32);
#endif
i2s_lcd_prepare_cmd_buffer(trans_desc, &lcd_cmd);
mount_config.buffer = (void *)trans_desc->data;
mount_config.length = trans_desc->data_length;
gdma_link_mount_buffers(bus->dma_link, 0, &mount_config, 1, NULL);
gpio_set_level(bus->dc_gpio_num, next_device->dc_levels.dc_cmd_level);
i2s_ll_tx_stop(bus->hal.dev);
i2s_ll_tx_reset(bus->hal.dev); // reset TX engine first
i2s_ll_start_out_link(bus->hal.dev);
esp_rom_delay_us(1);
// increase the pm lock reference count before starting a new transaction
if (bus->pm_lock) {
esp_pm_lock_acquire(bus->pm_lock);
}
i2s_ll_tx_start(bus->hal.dev);
// polling the trans done event
while (!(i2s_ll_get_intr_status(bus->hal.dev) & I2S_LL_EVENT_TX_EOF)) {}
// decrease pm lock reference count
if (bus->pm_lock) {
esp_pm_lock_release(bus->pm_lock);
}
bus->cur_trans = NULL;
// sending LCD color data to queue
trans_desc->trans_done_cb = next_device->on_color_trans_done;
trans_desc->user_ctx = next_device->user_ctx;
trans_desc->flags.dc_level = next_device->dc_levels.dc_data_level; // DC level for data transaction
i2s_lcd_prepare_color_buffer(trans_desc, color, color_size);
// send transaction to trans_queue
xQueueSend(next_device->trans_queue, &trans_desc, portMAX_DELAY);
next_device->num_trans_inflight++;
// enable interrupt and go into isr handler, where we fetch the transactions from trans_queue and start it
// we will go into `lcd_default_isr_handler` almost at once, because the "trans done" event is active at the moment
esp_intr_enable(bus->intr);
return ESP_OK;
}
static esp_err_t i2s_lcd_select_periph_clock(esp_lcd_i80_bus_handle_t bus, lcd_clock_source_t src)
{
// get clock source frequency
uint32_t src_clk_hz = 0;
ESP_RETURN_ON_ERROR(esp_clk_tree_src_get_freq_hz((soc_module_clk_t)src, ESP_CLK_TREE_SRC_FREQ_PRECISION_CACHED, &src_clk_hz),
TAG, "get clock source frequency failed");
// I2S clock source is binary compatible with lcd_clock_source_t
i2s_ll_tx_clk_set_src(bus->hal.dev, (i2s_clock_src_t)src);
i2s_ll_set_raw_mclk_div(bus->hal.dev, LCD_PERIPH_CLOCK_PRE_SCALE, 1, 0);
// save the resolution of the i80 bus
bus->resolution_hz = src_clk_hz / LCD_PERIPH_CLOCK_PRE_SCALE;
// create pm lock based on different clock source
// clock sources like PLL and XTAL will be turned off in light sleep
#if CONFIG_PM_ENABLE
ESP_RETURN_ON_ERROR(esp_pm_lock_create(ESP_PM_NO_LIGHT_SLEEP, 0, "i80_bus_lcd", &bus->pm_lock), TAG, "create pm lock failed");
#endif
return ESP_OK;
}
static esp_err_t i2s_lcd_init_dma_link(esp_lcd_i80_bus_handle_t bus)
{
i2s_ll_dma_enable_eof_on_fifo_empty(bus->hal.dev, true);
i2s_ll_dma_enable_owner_check(bus->hal.dev, true);
i2s_ll_dma_enable_auto_write_back(bus->hal.dev, true);
i2s_ll_set_out_link_addr(bus->hal.dev, gdma_link_get_head_addr(bus->dma_link));
i2s_ll_enable_dma(bus->hal.dev, true);
return ESP_OK;
}
static esp_err_t i2s_lcd_configure_gpio(esp_lcd_i80_bus_handle_t bus, const esp_lcd_i80_bus_config_t *bus_config)
{
int bus_id = bus->bus_id;
// check validation of GPIO number
bool valid_gpio = (bus_config->wr_gpio_num >= 0) && (bus_config->dc_gpio_num >= 0);
for (size_t i = 0; i < bus_config->bus_width; i++) {
valid_gpio = valid_gpio && (bus_config->data_gpio_nums[i] >= 0);
}
if (!valid_gpio) {
return ESP_ERR_INVALID_ARG;
}
// connect peripheral signals via GPIO matrix
// data line
for (size_t i = 0; i < bus_config->bus_width; i++) {
gpio_set_direction(bus_config->data_gpio_nums[i], GPIO_MODE_OUTPUT);
#if SOC_I2S_TRANS_SIZE_ALIGN_WORD
esp_rom_gpio_connect_out_signal(bus_config->data_gpio_nums[i], lcd_periph_i2s_signals.buses[bus_id].data_sigs[i + 8], false, false);
#else
esp_rom_gpio_connect_out_signal(bus_config->data_gpio_nums[i], lcd_periph_i2s_signals.buses[bus_id].data_sigs[i + SOC_I2S_MAX_DATA_WIDTH - bus_config->bus_width], false, false);
#endif
gpio_hal_iomux_func_sel(GPIO_PIN_MUX_REG[bus_config->data_gpio_nums[i]], PIN_FUNC_GPIO);
}
// WR signal (pclk)
gpio_set_direction(bus_config->wr_gpio_num, GPIO_MODE_OUTPUT);
esp_rom_gpio_connect_out_signal(bus_config->wr_gpio_num, lcd_periph_i2s_signals.buses[bus_id].wr_sig, true, false);
gpio_hal_iomux_func_sel(GPIO_PIN_MUX_REG[bus_config->wr_gpio_num], PIN_FUNC_GPIO);
// DC signal is controlled by software, set as general purpose IO
gpio_set_direction(bus_config->dc_gpio_num, GPIO_MODE_OUTPUT);
gpio_hal_iomux_func_sel(GPIO_PIN_MUX_REG[bus_config->dc_gpio_num], PIN_FUNC_GPIO);
return ESP_OK;
}
static void i2s_lcd_trigger_quick_trans_done_event(esp_lcd_i80_bus_handle_t bus)
{
// trigger a quick interrupt event by a dummy transaction, wait the LCD interrupt line goes active
// next time when esp_intr_enable is invoked, we can go into interrupt handler immediately
// where we dispatch transactions for i80 devices
static uint32_t fake_trigger = 0;
gdma_buffer_mount_config_t mount_config = {
.buffer = &fake_trigger,
.length = 4,
.flags = {
.mark_eof = true, // mark the "EOF" flag to trigger I2S EOF interrupt
.mark_final = true, // singly link list, mark final descriptor
}
};
gdma_link_mount_buffers(bus->dma_link, 0, &mount_config, 1, NULL);
i2s_ll_start_out_link(bus->hal.dev);
i2s_ll_tx_start(bus->hal.dev);
while (!(i2s_ll_get_intr_status(bus->hal.dev) & I2S_LL_EVENT_TX_EOF)) {}
}
static void lcd_i80_switch_devices(lcd_panel_io_i80_t *cur_device, lcd_panel_io_i80_t *next_device)
{
// the caller should make sure the next_device and cur_device are attached to the same bus
esp_lcd_i80_bus_t *bus = next_device->bus;
if (next_device != cur_device) {
// reconfigure PCLK for the new device
i2s_ll_tx_set_bck_div_num(bus->hal.dev, next_device->clock_prescale);
if (cur_device && cur_device->cs_gpio_num >= 0) { // de-assert current device
gpio_set_level(cur_device->cs_gpio_num, !cur_device->flags.cs_active_high);
}
if (next_device->cs_gpio_num >= 0) {
gpio_set_level(next_device->cs_gpio_num, next_device->flags.cs_active_high); // select the next device
}
// the WR signal (a.k.a the PCLK) generated by I2S is low level in idle stage
// but most of 8080 LCDs require the WR line to be in high level during idle stage
esp_rom_gpio_connect_out_signal(bus->wr_gpio_num, lcd_periph_i2s_signals.buses[bus->bus_id].wr_sig, !next_device->flags.pclk_idle_low, false);
}
bus->cur_device = next_device;
}
static IRAM_ATTR void lcd_default_isr_handler(void *args)
{
esp_lcd_i80_bus_t *bus = (esp_lcd_i80_bus_t *)args;
lcd_i80_trans_descriptor_t *trans_desc = NULL;
lcd_panel_io_i80_t *cur_device = NULL;
lcd_panel_io_i80_t *next_device = NULL;
BaseType_t high_task_woken = pdFALSE;
bool need_yield = false;
uint32_t intr_status = i2s_ll_get_intr_status(bus->hal.dev);
if (intr_status & I2S_LL_EVENT_TX_EOF) { // trans done event
// disable interrupt temporarily, only re-enable when there be remained transaction in the queue
esp_intr_disable(bus->intr);
trans_desc = bus->cur_trans; // the finished transaction
cur_device = bus->cur_device;// the working device
// process finished transaction
if (trans_desc) {
assert(trans_desc->i80_device == cur_device && "transaction device mismatch");
// decrease pm lock reference count
if (bus->pm_lock) {
esp_pm_lock_release(bus->pm_lock);
}
// device callback
if (trans_desc->trans_done_cb) {
if (trans_desc->trans_done_cb(&cur_device->base, NULL, trans_desc->user_ctx)) {
need_yield = true;
}
}
// move transaction to done_queue
high_task_woken = pdFALSE;
xQueueSendFromISR(cur_device->done_queue, &trans_desc, &high_task_woken);
if (high_task_woken == pdTRUE) {
need_yield = true;
}
bus->cur_trans = NULL;
}
// fetch transactions from devices' trans_queue
// Note: the first registered device will have the highest priority to be scheduled
LIST_FOREACH(next_device, &bus->device_list, device_list_entry) {
high_task_woken = pdFALSE;
if (xQueueReceiveFromISR(next_device->trans_queue, &trans_desc, &high_task_woken) == pdTRUE) {
if (high_task_woken == pdTRUE) {
need_yield = true;
}
// sanity check
assert(trans_desc);
// only clear the interrupt status when we're sure there still remains transaction to handle
i2s_ll_clear_intr_status(bus->hal.dev, I2S_LL_EVENT_TX_EOF);
// switch devices if necessary
lcd_i80_switch_devices(cur_device, next_device);
bus->cur_trans = trans_desc;
gpio_set_level(bus->dc_gpio_num, trans_desc->flags.dc_level);
// mount data to DMA links
gdma_buffer_mount_config_t mount_config = {
.buffer = (void *)trans_desc->data,
.length = trans_desc->data_length,
.flags = {
.mark_eof = true,
.mark_final = true, // singly link list, mark final descriptor
}
};
gdma_link_mount_buffers(bus->dma_link, 0, &mount_config, 1, NULL);
#if SOC_I2S_TRANS_SIZE_ALIGN_WORD
// switch to I2S 16bits mode, two WS cycle <=> one I2S FIFO
i2s_ll_tx_set_bits_mod(bus->hal.dev, 16);
#endif
// enable interrupt again, because the new transaction can trigger new trans done event
esp_intr_enable(bus->intr);
i2s_ll_tx_stop(bus->hal.dev);
i2s_ll_tx_reset(bus->hal.dev); // reset TX engine first
i2s_ll_start_out_link(bus->hal.dev);
esp_rom_delay_us(1);
// increase the pm lock reference count before starting a new transaction
if (bus->pm_lock) {
esp_pm_lock_acquire(bus->pm_lock);
}
i2s_ll_tx_start(bus->hal.dev);
break; // exit for-each loop
}
}
}
if (need_yield) {
portYIELD_FROM_ISR();
}
}