/* * SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD * * SPDX-License-Identifier: Apache-2.0 */ // #define LOG_LOCAL_LEVEL ESP_LOG_DEBUG ///////////////////////////////////////////////////////////////////////////////////////////////////////////// // 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 #include #include #include #include #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_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/dma_types.h" #include "hal/gpio_hal.h" #include "driver/gpio.h" #include "driver/periph_ctrl.h" #if SOC_I2S_LCD_I80_VARIANT #include "esp_private/i2s_platform.h" #include "soc/lcd_periph.h" #include "hal/i2s_hal.h" #include "hal/i2s_ll.h" #include "hal/i2s_types.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 unsigned long i2s_lcd_select_periph_clock(i2s_hal_context_t *hal); 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 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) 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 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 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 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 { 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 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_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) { 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_arg, TAG, "invalid argument"); // although I2S bus supports up to 24 parallel data lines, we restrict users to only use 8 or 16 bit width, due to limited GPIO numbers ESP_GOTO_ON_FALSE(bus_config->bus_width == 8 || bus_config->bus_width == 16, ESP_ERR_INVALID_ARG, err_arg, 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 size_t num_dma_nodes = 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_INTERNAL | MALLOC_CAP_DMA); ESP_GOTO_ON_FALSE(bus, ESP_ERR_NO_MEM, no_mem_bus, TAG, "no mem for i80 bus"); 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_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, CONFIG_LCD_PANEL_IO_FORMAT_BUF_SIZE, MALLOC_CAP_INTERNAL | MALLOC_CAP_DMA); #endif ESP_GOTO_ON_FALSE(bus->format_buffer, ESP_ERR_NO_MEM, no_mem_format, TAG, "no mem for format buffer"); // I2S0 has the LCD mode, but the LCD mode can't work with other modes at the same time, we need to register the driver object to the I2S platform ESP_GOTO_ON_ERROR(i2s_priv_register_object(bus, 0), no_slot, TAG, "register to I2S platform failed"); bus->bus_id = 0; // initialize HAL layer i2s_hal_init(&bus->hal, bus->bus_id); // set peripheral clock resolution bus->resolution_hz = i2s_lcd_select_periph_clock(&bus->hal); // 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 = ESP_INTR_FLAG_INTRDISABLED | ESP_INTR_FLAG_SHARED; ret = esp_intr_alloc_intrstatus(lcd_periph_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, no_int, 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_bypass_pcm(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_set_chan_mod(bus->hal.dev, 1); // 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, invalid_gpio, 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 %zuHz", bus->bus_id, bus, bus->num_dma_nodes, bus->resolution_hz); return ESP_OK; invalid_gpio: esp_intr_free(bus->intr); no_int: i2s_priv_deregister_object(bus->bus_id); no_slot: free(bus->format_buffer); no_mem_format: free(bus); no_mem_bus: err_arg: 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; esp_intr_free(bus->intr); i2s_priv_deregister_object(bus_id); free(bus->format_buffer); 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"); // 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 %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->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->cb_user_data = io_config->user_data; 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; // 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=%uHz", 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; } 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 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 * 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"); // before issue a polling transaction, need to wait queued transactions finished 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; 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); lcd_com_mount_dma_data(bus->dma_nodes, trans_desc->data, trans_desc->data_length); 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 beeing feed to I2S FIFO // in fact, this is only needed when LCD pixel clock is set too high esp_rom_delay_us(1); 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); lcd_com_mount_dma_data(bus->dma_nodes, trans_desc->data, trans_desc->data_length); 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)) {} } 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 * DMA_DESCRIPTOR_BUFFER_MAX_SIZE) && "color bytes too long, enlarge max_transfer_bytes"); // before issue a polling transaction, need to wait queued transactions finished 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; 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); lcd_com_mount_dma_data(bus->dma_nodes, trans_desc->data, trans_desc->data_length); 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); 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)) {} bus->cur_trans = NULL; // sending LCD color data to queue trans_desc->trans_done_cb = next_device->on_color_trans_done; trans_desc->cb_user_data = next_device->cb_user_data; 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 unsigned long i2s_lcd_select_periph_clock(i2s_hal_context_t *hal) { unsigned long resolution_hz = 0; i2s_clock_src_t clock_source; #if CONFIG_LCD_PERIPH_CLK_SRC_PLL160M resolution_hz = 160000000 / LCD_PERIPH_CLOCK_PRE_SCALE; clock_source = I2S_CLK_D2CLK; #else #error "invalid LCD peripheral clock source" #endif i2s_ll_tx_clk_set_src(hal->dev, clock_source); i2s_ll_mclk_div_t clk_cal_config = { .mclk_div = LCD_PERIPH_CLOCK_PRE_SCALE, .a = 1, .b = 0, }; i2s_ll_tx_set_clk(hal->dev, &clk_cal_config); return resolution_hz; } static esp_err_t i2s_lcd_init_dma_link(esp_lcd_i80_bus_handle_t bus) { 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 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, (uint32_t)bus->dma_nodes); 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_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_signals.buses[bus_id].data_sigs[i + SOC_LCD_I80_BUS_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_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; lcd_com_mount_dma_data(bus->dma_nodes, &fake_trigger, 4); 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) { // de-assert current device gpio_set_level(cur_device->cs_gpio_num, !cur_device->flags.cs_active_high); } 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_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"); // 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 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 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 lcd_com_mount_dma_data(bus->dma_nodes, trans_desc->data, trans_desc->data_length); #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); i2s_ll_tx_start(bus->hal.dev); break; // exit for-each loop } } } if (need_yield) { portYIELD_FROM_ISR(); } } #endif // SOC_I2S_LCD_I80_VARIANT