[display] Loop on the reader's step in display drivers and cap mipi_spi args in the reader

esphome/components/epaper_spi/epaper_spi.cpp

@@ -318,16 +318,18 @@ void EPaperBase::on_safe_shutdown() { this->deep_sleep(); }
 void EPaperBase::send_init_sequence_(const uint8_t *sequence, size_t length) {
   display::InitSequenceReader reader(sequence, length);
   display::InitSequenceEntry entry;
-  while (reader.next(entry)) {
-    if (entry.is_delay()) {
+  while (auto step = reader.next(entry)) {
+    if (step == display::INIT_SEQUENCE_STEP_MALFORMED) {
+      this->mark_failed(LOG_STR("Malformed init sequence"));
+      return;
+    }
+    if (step == display::INIT_SEQUENCE_STEP_DELAY) {
       ESP_LOGV(TAG, "Delay %dms", entry.value);
       delay(entry.value);
     } else {
       this->cmd_data(entry.value, entry.args, entry.count);
     }
   }
-  if (reader.malformed())
-    this->mark_failed(LOG_STR("Malformed init sequence"));
 }
 
 bool EPaperBase::initialise(bool partial) {

esphome/components/mipi_dsi/mipi_dsi.cpp

@@ -126,8 +126,12 @@ void MipiDsi::setup() {
   }
   display::InitSequenceReader reader(this->init_sequence_, this->init_sequence_len_);
   display::InitSequenceEntry entry;
-  while (reader.next(entry)) {
-    if (entry.is_delay()) {
+  while (auto step = reader.next(entry)) {
+    if (step == display::INIT_SEQUENCE_STEP_MALFORMED) {
+      this->mark_failed(LOG_STR("Malformed init sequence"));
+      return;
+    }
+    if (step == display::INIT_SEQUENCE_STEP_DELAY) {
       ESP_LOGD(TAG, "Delay %dms", entry.value);
       delay(entry.value);
       continue;
@@ -153,10 +157,6 @@ void MipiDsi::setup() {
     if (cmd == SLEEP_OUT)
       delay(10);
   }
-  if (reader.malformed()) {
-    this->mark_failed(LOG_STR("Malformed init sequence"));
-    return;
-  }
   this->io_lock_ = xSemaphoreCreateBinary();
   esp_lcd_dpi_panel_event_callbacks_t cbs = {
       .on_color_trans_done = notify_refresh_ready,

esphome/components/mipi_rgb/mipi_rgb.cpp

@@ -77,8 +77,12 @@ void MipiRgbSpi::write_data_(uint8_t value) {
 void MipiRgbSpi::write_init_sequence_() {
   display::InitSequenceReader reader(this->init_sequence_, this->init_sequence_len_);
   display::InitSequenceEntry entry;
-  while (reader.next(entry)) {
-    if (entry.is_delay()) {
+  while (auto step = reader.next(entry)) {
+    if (step == display::INIT_SEQUENCE_STEP_MALFORMED) {
+      this->mark_failed(LOG_STR("Malformed init sequence"));
+      return;
+    }
+    if (step == display::INIT_SEQUENCE_STEP_DELAY) {
       ESP_LOGD(TAG, "Delay %dms", entry.value);
       delay(entry.value);
       continue;
@@ -95,10 +99,6 @@ void MipiRgbSpi::write_init_sequence_() {
     if (cmd == SLEEP_OUT)
       delay(10);
   }
-  if (reader.malformed()) {
-    this->mark_failed(LOG_STR("Malformed init sequence"));
-    return;
-  }
   // this->spi_teardown();  // SPI not needed after this
   delay(10);
 }

esphome/components/mipi_spi/mipi_spi.h

@@ -170,24 +170,20 @@ class MipiSpi : public display::Display,
     display::InitSequenceEntry entry;
     // The sequence is in flash, which SPI DMA (and ESP8266 byte loads) cannot read
     uint8_t args[INIT_SEQUENCE_MAX_ARGS];
-    while (reader.next(entry)) {
-      if (entry.is_delay()) {
+    while (auto step = reader.next(entry, sizeof(args))) {
+      if (step == display::INIT_SEQUENCE_STEP_MALFORMED) {
+        this->mark_failed(LOG_STR("Malformed init sequence"));
+        return;
+      }
+      if (step == display::INIT_SEQUENCE_STEP_DELAY) {
         const uint8_t ms = entry.value != 0 ? entry.value : clamp_at_least((int) (when - millis()), 0);
         esph_log_d(TAG, "Delay %dms", ms);
         delay(ms);
         continue;
       }
-      if (entry.count > sizeof(args)) {
-        this->mark_failed(LOG_STR("Malformed init sequence"));
-        return;
-      }
       progmem_memcpy(args, entry.args, entry.count);
       this->write_command_(entry.value, args, entry.count);
     }
-    if (reader.malformed()) {
-      this->mark_failed(LOG_STR("Malformed init sequence"));
-      return;
-    }
     this->reset_params_();
     // Marks init as done, so later commands log at verbose level instead of debug
     this->init_sequence_len_ = 0;

esphome/components/st7305/st7305.cpp

@@ -57,12 +57,8 @@ void ST7305::reset_() {
 
 void ST7305::send_init_sequence_() {
   display::InitSequenceEntry entry;
-  while (this->init_reader_.next(entry)) {
-    if (entry.is_delay()) {
-      // Resume the sequence after the delay instead of blocking the main loop.
-      this->set_timeout(STARTUP_TIMEOUT_ID, entry.value, [this]() { this->send_init_sequence_(); });
-      return;
-    }
+  display::InitSequenceStep step;
+  while ((step = this->init_reader_.next(entry)) == display::INIT_SEQUENCE_STEP_COMMAND) {
     this->enable();
     this->send_command_(entry.value);
     if (entry.count != 0) {
@@ -72,7 +68,10 @@ void ST7305::send_init_sequence_() {
     }
     this->disable();
   }
-  if (this->init_reader_.malformed()) {
+  if (step == display::INIT_SEQUENCE_STEP_DELAY) {
+    // Resume the sequence after the delay instead of blocking the main loop.
+    this->set_timeout(STARTUP_TIMEOUT_ID, entry.value, [this]() { this->send_init_sequence_(); });
+  } else if (step == display::INIT_SEQUENCE_STEP_MALFORMED) {
     this->mark_failed(LOG_STR("Malformed init sequence"));
   } else {
     this->finish_init_();