/*
* SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: Apache-2.0
*/
// #define LOG_LOCAL_LEVEL ESP_LOG_DEBUG
#include <stdlib.h>
#include <string.h>
#include <sys/cdefs.h>
#include <sys/param.h>
#include <sys/queue.h>
#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_rom_gpio.h"
#include "soc/soc_caps.h"
#include "hal/dma_types.h"
#include "hal/gpio_hal.h"
#include "esp_private/gdma.h"
#include "driver/gpio.h"
#include "driver/periph_ctrl.h"
#if SOC_LCDCAM_SUPPORTED
#include "esp_lcd_common.h"
#include "soc/lcd_periph.h"
#include "hal/lcd_ll.h"
#include "hal/lcd_hal.h"
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 lcd_i80_init_dma_link(esp_lcd_i80_bus_handle_t bus);
static void lcd_periph_trigger_quick_trans_done_event(esp_lcd_i80_bus_handle_t bus);
static esp_err_t lcd_i80_select_periph_clock(esp_lcd_i80_bus_handle_t bus, lcd_clock_source_t clk_src);
static esp_err_t lcd_i80_bus_configure_gpio(esp_lcd_i80_bus_handle_t bus, const esp_lcd_i80_bus_config_t *bus_config);
static void lcd_i80_switch_devices(lcd_panel_io_i80_t *cur_device, lcd_panel_io_i80_t *next_device);
static void lcd_start_transaction(esp_lcd_i80_bus_t *bus, lcd_i80_trans_descriptor_t *trans_desc);
static IRAM_ATTR void lcd_default_isr_handler(void *args);
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)
lcd_hal_context_t hal; // Hal object
size_t bus_width; // Number of data lines
intr_handle_t intr; // LCD peripheral interrupt handle
esp_pm_lock_handle_t pm_lock; // Power management lock
size_t num_dma_nodes; // Number of DMA descriptors
uint8_t *format_buffer; // The driver allocates an internal buffer for DMA to do data format transformer
size_t resolution_hz; // LCD_CLK resolution, determined by selected clock source
gdma_channel_handle_t dma_chan; // DMA channel handle
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
dma_descriptor_t dma_nodes[]; // DMA descriptor pool, the descriptors are shared by all i80 devices
};
struct lcd_i80_trans_descriptor_t {
lcd_panel_io_i80_t *i80_device; // i80 device issuing this transaction
int cmd_value; // Command value
uint32_t cmd_cycles; // Command cycles
const void *data; // Data buffer
uint32_t data_length; // Data buffer size
void *cb_user_data; // private data used by trans_done_cb
bool (*trans_done_cb)(esp_lcd_panel_io_handle_t panel_io, void *user_data, void *event_data); // transaction done callback
};
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
unsigned int 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 *cb_user_data; // private data used when transfer color data
bool (*on_color_trans_done)(esp_lcd_panel_io_handle_t panel_io, void *user_data, void *event_data); // color data trans done callback
LIST_ENTRY(lcd_panel_io_i80_t) device_list_entry; // Entry of i80 device list
struct {
unsigned int dc_idle_level: 1; // Level of DC line in IDLE phase
unsigned int dc_cmd_level: 1; // Level of DC line in CMD phase
unsigned int dc_dummy_level: 1; // Level of DC line in DUMMY 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 reverse_color_bits: 1; // Reverse the data bits, D[N:0] -> D[0:N]
unsigned int swap_color_bytes: 1; // Swap adjacent two data bytes before sending out
unsigned int pclk_active_neg: 1; // The display will write data lines when there's a falling edge on WR line
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)
{
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");
size_t num_dma_nodes = bus_config->max_transfer_bytes / DMA_DESCRIPTOR_BUFFER_MAX_SIZE + 1;
// DMA descriptors must be placed in internal SRAM
bus = heap_caps_calloc(1, sizeof(esp_lcd_i80_bus_t) + num_dma_nodes * sizeof(dma_descriptor_t), MALLOC_CAP_DMA);
ESP_GOTO_ON_FALSE(bus, ESP_ERR_NO_MEM, err, TAG, "no mem for i80 bus");
bus->num_dma_nodes = num_dma_nodes;
bus->bus_id = -1;
bus->format_buffer = heap_caps_calloc(1, CONFIG_LCD_PANEL_IO_FORMAT_BUF_SIZE, MALLOC_CAP_DMA);
ESP_GOTO_ON_FALSE(bus->format_buffer, ESP_ERR_NO_MEM, err, TAG, "no mem for format buffer");
// register to platform
int bus_id = lcd_com_register_device(LCD_COM_DEVICE_TYPE_I80, bus);
ESP_GOTO_ON_FALSE(bus_id >= 0, ESP_ERR_NOT_FOUND, err, TAG, "no free i80 bus slot");
bus->bus_id = bus_id;
// enable APB to access LCD registers
periph_module_enable(lcd_periph_signals.buses[bus_id].module);
// initialize HAL layer, so we can call LL APIs later
lcd_hal_init(&bus->hal, bus_id);
// reset peripheral and FIFO
lcd_ll_reset(bus->hal.dev);
lcd_ll_fifo_reset(bus->hal.dev);
lcd_ll_enable_clock(bus->hal.dev, true);
// set peripheral clock resolution
ret = lcd_i80_select_periph_clock(bus, bus_config->clk_src);
ESP_GOTO_ON_ERROR(ret, err, TAG, "select periph clock %d failed", bus_config->clk_src);
// install interrupt service, (LCD peripheral shares the same interrupt source with Camera peripheral with different mask)
// interrupt is disabled by default
int isr_flags = ESP_INTR_FLAG_INTRDISABLED | ESP_INTR_FLAG_SHARED;
ret = esp_intr_alloc_intrstatus(lcd_periph_signals.buses[bus_id].irq_id, isr_flags,
(uint32_t)lcd_ll_get_interrupt_status_reg(bus->hal.dev),
LCD_LL_EVENT_TRANS_DONE, lcd_default_isr_handler, bus, &bus->intr);
ESP_GOTO_ON_ERROR(ret, err, TAG, "install interrupt failed");
lcd_ll_enable_interrupt(bus->hal.dev, LCD_LL_EVENT_TRANS_DONE, false); // disable all interrupts
lcd_ll_clear_interrupt_status(bus->hal.dev, UINT32_MAX); // clear pending interrupt
// install DMA service
ret = lcd_i80_init_dma_link(bus);
ESP_GOTO_ON_ERROR(ret, err, TAG, "install DMA failed");
// enable 8080 mode and set bus width
lcd_ll_enable_rgb_mode(bus->hal.dev, false);
lcd_ll_set_data_width(bus->hal.dev, bus_config->bus_width);
bus->bus_width = lcd_ll_get_data_width(bus->hal.dev);
// number of data cycles is controlled by DMA buffer size
lcd_ll_enable_output_always_on(bus->hal.dev, true);
// enable trans done interrupt
lcd_ll_enable_interrupt(bus->hal.dev, LCD_LL_EVENT_TRANS_DONE, 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`
lcd_periph_trigger_quick_trans_done_event(bus);
// configure GPIO
ret = lcd_i80_bus_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;
*ret_bus = bus;
ESP_LOGD(TAG, "new i80 bus(%d) @%p, %zu dma nodes", bus_id, bus, bus->num_dma_nodes);
return ESP_OK;
err:
if (bus) {
if (bus->intr) {
esp_intr_free(bus->intr);
}
if (bus->dma_chan) {
gdma_disconnect(bus->dma_chan);
gdma_del_channel(bus->dma_chan);
}
if (bus->bus_id >= 0) {
periph_module_disable(lcd_periph_signals.buses[bus->bus_id].module);
lcd_com_remove_device(LCD_COM_DEVICE_TYPE_I80, 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;
lcd_com_remove_device(LCD_COM_DEVICE_TYPE_I80, bus_id);
periph_module_disable(lcd_periph_signals.buses[bus_id].module);
gdma_disconnect(bus->dma_chan);
gdma_del_channel(bus->dma_chan);
esp_intr_free(bus->intr);
free(bus->format_buffer);
if (bus->pm_lock) {
esp_pm_lock_delete(bus->pm_lock);
}
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;
ESP_GOTO_ON_FALSE(bus && io_config && ret_io, ESP_ERR_INVALID_ARG, err, TAG, "invalid argument");
// check if pixel clock setting is valid
uint32_t pclk_prescale = bus->resolution_hz / io_config->pclk_hz;
ESP_GOTO_ON_FALSE(pclk_prescale > 0 && pclk_prescale <= LCD_LL_CLOCK_PRESCALE_MAX, ESP_ERR_NOT_SUPPORTED, err, TAG,
"prescaler can't satisfy PCLK clock %u", io_config->pclk_hz);
i80_device = calloc(1, sizeof(lcd_panel_io_i80_t) + io_config->trans_queue_depth * sizeof(lcd_i80_trans_descriptor_t));
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->lcd_cmd_bits = io_config->lcd_cmd_bits;
i80_device->lcd_param_bits = io_config->lcd_param_bits;
i80_device->queue_size = io_config->trans_queue_depth;
i80_device->clock_prescale = pclk_prescale;
i80_device->pclk_hz = bus->resolution_hz / pclk_prescale;
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->dc_levels.dc_dummy_level = io_config->dc_levels.dc_dummy_level;
i80_device->dc_levels.dc_idle_level = io_config->dc_levels.dc_idle_level;
i80_device->cs_gpio_num = io_config->cs_gpio_num;
i80_device->flags.reverse_color_bits = io_config->flags.reverse_color_bits;
i80_device->flags.swap_color_bytes = io_config->flags.swap_color_bytes;
i80_device->flags.cs_active_high = io_config->flags.cs_active_high;
i80_device->flags.pclk_idle_low = io_config->flags.pclk_idle_low;
i80_device->flags.pclk_active_neg = io_config->flags.pclk_active_neg;
i80_device->on_color_trans_done = io_config->on_color_trans_done;
i80_device->cb_user_data = io_config->user_data;
// 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;
// we only configure the CS GPIO as output, don't connect to the peripheral signal at the moment
// we will connect the CS GPIO to peripheral signal when switching devices in lcd_i80_switch_devices()
gpio_set_level(io_config->cs_gpio_num, !io_config->flags.cs_active_high);
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)", i80_device, bus->bus_id);
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;
}
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;
// wait all pending transaction to finish
for (size_t i = 0; i < i80_device->num_trans_inflight; i++) {
xQueueReceive(i80_device->done_queue, &trans_desc, portMAX_DELAY);
}
// remove from device list
portENTER_CRITICAL(&bus->spinlock);
LIST_REMOVE(i80_device, device_list_entry);
portEXIT_CRITICAL(&bus->spinlock);
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 void i80_lcd_prepare_cmd_buffer(esp_lcd_i80_bus_t *bus, lcd_panel_io_i80_t *i80_device, void *lcd_cmd)
{
uint8_t *from = (uint8_t *)lcd_cmd;
if (bus->bus_width < i80_device->lcd_cmd_bits) {
// LCD is big-endian, e.g. to send command 0x1234, byte 0x12 should appear on the bus first
// However, the i80 peripheral will send 0x34 first, so we reversed the order below
int start = 0;
int end = i80_device->lcd_cmd_bits / 8 - 1;
lcd_com_reverse_buffer_bytes(from, start, end);
}
}
static uint32_t i80_lcd_prepare_param_buffer(esp_lcd_i80_bus_t *bus, lcd_panel_io_i80_t *i80_device, const void *lcd_param, size_t param_size)
{
int param_per_size = i80_device->lcd_param_bits / 8;
int param_num = param_size / param_per_size;
const uint8_t *from = (const uint8_t *)lcd_param;
uint8_t *to = bus->format_buffer;
uint8_t step = bus->bus_width / 8;
int param_cycle = i80_device->lcd_param_bits / bus->bus_width;
// in case bus_width=16 and param_bits=8, we still need 1 param_cycle
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;
// expand the width of parameters when necessary
for (int i = 0; i < ele_cycles; i++) {
for (int j = 0; j < bytes_to_copy; j++) {
to[j] = from[cnt_from++];
}
to += step;
}
return to - bus->format_buffer;
}
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 * DMA_DESCRIPTOR_BUFFER_MAX_SIZE) && "parameter bytes too long, enlarge max_transfer_bytes");
assert(param_size <= CONFIG_LCD_PANEL_IO_FORMAT_BUF_SIZE && "format buffer too small, increase CONFIG_LCD_PANEL_IO_FORMAT_BUF_SIZE");
uint32_t cmd_cycles = next_device->lcd_cmd_bits / bus->bus_width;
// in case bus_width=16 and cmd_bits=8, we still need 1 cmd_cycle
if (cmd_cycles * bus->bus_width < next_device->lcd_cmd_bits) {
cmd_cycles++;
}
i80_lcd_prepare_cmd_buffer(bus, next_device, &lcd_cmd);
uint32_t param_len = i80_lcd_prepare_param_buffer(bus, next_device, param, param_size);
// wait all pending transaction in the queue to finish
for (size_t i = 0; i < next_device->num_trans_inflight; i++) {
xQueueReceive(next_device->done_queue, &trans_desc, portMAX_DELAY);
}
next_device->num_trans_inflight = 0;
uint32_t intr_status = lcd_ll_get_interrupt_status(bus->hal.dev);
lcd_ll_clear_interrupt_status(bus->hal.dev, intr_status);
// switch devices if necessary
lcd_i80_switch_devices(cur_device, next_device);
// set data format
lcd_ll_reverse_data_byte_order(bus->hal.dev, false);
lcd_ll_reverse_data_bit_order(bus->hal.dev, false);
lcd_ll_reverse_data_8bits_order(bus->hal.dev, next_device->lcd_param_bits > bus->bus_width);
bus->cur_trans = NULL;
bus->cur_device = next_device;
// package a transaction
trans_desc = &next_device->trans_pool[0];
trans_desc->i80_device = next_device;
trans_desc->cmd_cycles = cmd_cycles;
trans_desc->cmd_value = lcd_cmd;
trans_desc->data = param ? bus->format_buffer : NULL;
trans_desc->data_length = param ? param_len : 0;
trans_desc->trans_done_cb = NULL; // no callback for parameter transaction
// mount data to DMA links
lcd_com_mount_dma_data(bus->dma_nodes, trans_desc->data, trans_desc->data_length);
// increase the pm lock reference count before starting a new transaction
if (bus->pm_lock) {
esp_pm_lock_acquire(bus->pm_lock);
}
lcd_start_transaction(bus, trans_desc);
// polling the trans done event, but don't clear the event status
while (!(lcd_ll_get_interrupt_status(bus->hal.dev) & LCD_LL_EVENT_TRANS_DONE)) {}
// decrease pm lock reference count
if (bus->pm_lock) {
esp_pm_lock_release(bus->pm_lock);
}
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 *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;
assert(color_size <= (bus->num_dma_nodes * DMA_DESCRIPTOR_BUFFER_MAX_SIZE) && "color bytes too long, enlarge max_transfer_bytes");
// in case bus_width=16 and cmd_bits=8, we still need 1 cmd_cycle
uint32_t cmd_cycles = i80_device->lcd_cmd_bits / bus->bus_width;
if (cmd_cycles * bus->bus_width < i80_device->lcd_cmd_bits) {
cmd_cycles++;
}
i80_lcd_prepare_cmd_buffer(bus, i80_device, &lcd_cmd);
if (i80_device->num_trans_inflight < i80_device->queue_size) {
trans_desc = &i80_device->trans_pool[i80_device->num_trans_inflight];
} else {
// transaction pool has used up, recycle one from done_queue
xQueueReceive(i80_device->done_queue, &trans_desc, portMAX_DELAY);
i80_device->num_trans_inflight--;
}
trans_desc->i80_device = i80_device;
trans_desc->cmd_cycles = cmd_cycles;
trans_desc->cmd_value = lcd_cmd;
trans_desc->data = color;
trans_desc->data_length = color_size;
trans_desc->trans_done_cb = i80_device->on_color_trans_done;
trans_desc->cb_user_data = i80_device->cb_user_data;
// send transaction to trans_queue
xQueueSend(i80_device->trans_queue, &trans_desc, portMAX_DELAY);
i80_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 lcd_i80_select_periph_clock(esp_lcd_i80_bus_handle_t bus, lcd_clock_source_t clk_src)
{
esp_err_t ret = ESP_OK;
lcd_ll_set_group_clock_src(bus->hal.dev, clk_src, LCD_PERIPH_CLOCK_PRE_SCALE, 1, 0);
switch (clk_src) {
case LCD_CLK_SRC_PLL160M:
bus->resolution_hz = 160000000 / LCD_PERIPH_CLOCK_PRE_SCALE;
#if CONFIG_PM_ENABLE
ret = esp_pm_lock_create(ESP_PM_APB_FREQ_MAX, 0, "i80_bus_lcd", &bus->pm_lock);
ESP_RETURN_ON_ERROR(ret, TAG, "create ESP_PM_APB_FREQ_MAX lock failed");
ESP_LOGD(TAG, "installed ESP_PM_APB_FREQ_MAX lock");
#endif
break;
case LCD_CLK_SRC_XTAL:
bus->resolution_hz = rtc_clk_xtal_freq_get() * 1000000 / LCD_PERIPH_CLOCK_PRE_SCALE;
break;
default:
ESP_RETURN_ON_FALSE(false, ESP_ERR_NOT_SUPPORTED, TAG, "unsupported clock source: %d", clk_src);
break;
}
return ret;
}
static esp_err_t lcd_i80_init_dma_link(esp_lcd_i80_bus_handle_t bus)
{
esp_err_t ret = ESP_OK;
// chain DMA descriptors
for (int i = 0; i < bus->num_dma_nodes; i++) {
bus->dma_nodes[i].dw0.owner = DMA_DESCRIPTOR_BUFFER_OWNER_CPU;
bus->dma_nodes[i].next = &bus->dma_nodes[i + 1];
}
bus->dma_nodes[bus->num_dma_nodes - 1].next = NULL; // one-off DMA chain
// alloc DMA channel and connect to LCD peripheral
gdma_channel_alloc_config_t dma_chan_config = {
.direction = GDMA_CHANNEL_DIRECTION_TX,
};
ret = gdma_new_channel(&dma_chan_config, &bus->dma_chan);
ESP_GOTO_ON_ERROR(ret, err, TAG, "alloc DMA channel failed");
gdma_connect(bus->dma_chan, GDMA_MAKE_TRIGGER(GDMA_TRIG_PERIPH_LCD, 0));
gdma_strategy_config_t strategy_config = {
.auto_update_desc = true,
.owner_check = true
};
gdma_apply_strategy(bus->dma_chan, &strategy_config);
return ESP_OK;
err:
if (bus->dma_chan) {
gdma_del_channel(bus->dma_chan);
}
return ret;
}
static esp_err_t lcd_i80_bus_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
for (size_t i = 0; i < bus_config->bus_width; i++) {
gpio_set_direction(bus_config->data_gpio_nums[i], GPIO_MODE_OUTPUT);
esp_rom_gpio_connect_out_signal(bus_config->data_gpio_nums[i], lcd_periph_signals.buses[bus_id].data_sigs[i], false, false);
gpio_hal_iomux_func_sel(GPIO_PIN_MUX_REG[bus_config->data_gpio_nums[i]], PIN_FUNC_GPIO);
}
gpio_set_direction(bus_config->dc_gpio_num, GPIO_MODE_OUTPUT);
esp_rom_gpio_connect_out_signal(bus_config->dc_gpio_num, lcd_periph_signals.buses[bus_id].dc_sig, false, false);
gpio_hal_iomux_func_sel(GPIO_PIN_MUX_REG[bus_config->dc_gpio_num], PIN_FUNC_GPIO);
gpio_set_direction(bus_config->wr_gpio_num, GPIO_MODE_OUTPUT);
esp_rom_gpio_connect_out_signal(bus_config->wr_gpio_num, lcd_periph_signals.buses[bus_id].wr_sig, false, false);
gpio_hal_iomux_func_sel(GPIO_PIN_MUX_REG[bus_config->wr_gpio_num], PIN_FUNC_GPIO);
return ESP_OK;
}
static void lcd_periph_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
lcd_ll_set_phase_cycles(bus->hal.dev, 0, 1, 0);
lcd_ll_start(bus->hal.dev);
while (!(lcd_ll_get_interrupt_status(bus->hal.dev) & LCD_LL_EVENT_TRANS_DONE)) {}
}
static void lcd_start_transaction(esp_lcd_i80_bus_t *bus, lcd_i80_trans_descriptor_t *trans_desc)
{
// by default, the dummy phase is disabled because it's not common for most LCDs
// Number of data phase cycles are controlled by DMA buffer length, we only need to enable/disable the phase here
lcd_ll_set_phase_cycles(bus->hal.dev, trans_desc->cmd_cycles, 0, trans_desc->data ? 1 : 0);
lcd_ll_set_command(bus->hal.dev, bus->bus_width, trans_desc->cmd_value);
if (trans_desc->data) { // some specific LCD commands can have no parameters
gdma_start(bus->dma_chan, (intptr_t)(bus->dma_nodes));
}
lcd_ll_start(bus->hal.dev);
}
static void lcd_i80_switch_devices(lcd_panel_io_i80_t *cur_device, lcd_panel_io_i80_t *next_device)
{
// we assume 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
lcd_ll_set_pixel_clock_prescale(bus->hal.dev, next_device->clock_prescale);
lcd_ll_set_clock_idle_level(bus->hal.dev, !next_device->flags.pclk_idle_low);
lcd_ll_set_pixel_clock_edge(bus->hal.dev, next_device->flags.pclk_active_neg);
// configure DC line level for the new device
lcd_ll_set_dc_level(bus->hal.dev, next_device->dc_levels.dc_idle_level, next_device->dc_levels.dc_cmd_level,
next_device->dc_levels.dc_dummy_level, next_device->dc_levels.dc_data_level);
if (cur_device) {
// disconnect current CS GPIO from peripheral signal
esp_rom_gpio_connect_out_signal(cur_device->cs_gpio_num, SIG_GPIO_OUT_IDX, false, false);
}
// connect CS signal to the new device
esp_rom_gpio_connect_out_signal(next_device->cs_gpio_num, lcd_periph_signals.buses[bus->bus_id].cs_sig,
next_device->flags.cs_active_high, false);
}
}
IRAM_ATTR static 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 = lcd_ll_get_interrupt_status(bus->hal.dev);
if (intr_status & LCD_LL_EVENT_TRANS_DONE) {
// 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, trans_desc->cb_user_data, NULL)) {
need_yield = true;
}
}
// move transaction to done_queue
// there won't be case that will overflow the queue, so skip checking the return value
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;
}
// only clear the interrupt status when we're sure there still remains transaction to handle
lcd_ll_clear_interrupt_status(bus->hal.dev, intr_status);
// switch devices if necessary
lcd_i80_switch_devices(cur_device, next_device);
// only reverse data bit/bytes for color data
lcd_ll_reverse_data_bit_order(bus->hal.dev, next_device->flags.reverse_color_bits);
lcd_ll_reverse_data_byte_order(bus->hal.dev, next_device->flags.swap_color_bytes);
lcd_ll_reverse_data_8bits_order(bus->hal.dev, false);
bus->cur_trans = trans_desc;
bus->cur_device = next_device;
// mount data to DMA links
lcd_com_mount_dma_data(bus->dma_nodes, trans_desc->data, trans_desc->data_length);
// enable interrupt again, because the new transaction can trigger new trans done event
esp_intr_enable(bus->intr);
// increase the pm lock reference count before starting a new transaction
if (bus->pm_lock) {
esp_pm_lock_acquire(bus->pm_lock);
}
lcd_start_transaction(bus, trans_desc);
break; // exit for-each loop
}
}
}
if (need_yield) {
portYIELD_FROM_ISR();
}
}
#endif // SOC_LCDCAM_SUPPORTED