From 5aad83f90fbc64d0debfeb8dc8f25f8b03f58abb Mon Sep 17 00:00:00 2001 From: Chen Jichang Date: Thu, 7 Aug 2025 13:09:00 +0800 Subject: [PATCH] fix(rmt): treat loop once as no loop --- components/driver/rmt/rmt_tx.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/components/driver/rmt/rmt_tx.c b/components/driver/rmt/rmt_tx.c index 94385cfe50..77506a4dee 100644 --- a/components/driver/rmt/rmt_tx.c +++ b/components/driver/rmt/rmt_tx.c @@ -475,7 +475,7 @@ esp_err_t rmt_transmit(rmt_channel_handle_t channel, rmt_encoder_t *encoder, con ESP_RETURN_ON_FALSE(channel && encoder && payload && payload_bytes && config, ESP_ERR_INVALID_ARG, TAG, "invalid argument"); ESP_RETURN_ON_FALSE(channel->direction == RMT_CHANNEL_DIRECTION_TX, ESP_ERR_INVALID_ARG, TAG, "invalid channel direction"); #if !SOC_RMT_SUPPORT_TX_LOOP_COUNT - ESP_RETURN_ON_FALSE(config->loop_count <= 0, ESP_ERR_NOT_SUPPORTED, TAG, "loop count is not supported"); + ESP_RETURN_ON_FALSE(config->loop_count <= 1, ESP_ERR_NOT_SUPPORTED, TAG, "loop count is not supported"); #endif // !SOC_RMT_SUPPORT_TX_LOOP_COUNT #if CONFIG_RMT_ISR_IRAM_SAFE // payload is retrieved by the encoder, we should make sure it's still accessible even when the cache is disabled @@ -500,7 +500,8 @@ esp_err_t rmt_transmit(rmt_channel_handle_t channel, rmt_encoder_t *encoder, con t->encoder = encoder; t->payload = payload; t->payload_bytes = payload_bytes; - t->loop_count = config->loop_count; + // treat loop_count == 1 as no loop + t->loop_count = config->loop_count == 1 ? 0 : config->loop_count; t->remain_loop_count = t->loop_count; t->flags.eot_level = config->flags.eot_level; @@ -603,7 +604,7 @@ static size_t IRAM_ATTR rmt_encode_check_result(rmt_tx_channel_t *tx_chan, rmt_t // for loop transaction, the memory block should accommodate all encoded RMT symbols and an extra EOF symbol if (t->loop_count != 0) { size_t limit_symbols = tx_chan->base.mem_block_num * SOC_RMT_MEM_WORDS_PER_CHANNEL; - if (unlikely(encoded_symbols > limit_symbols)) { + if (unlikely(encoded_symbols > limit_symbols || (encoded_symbols == limit_symbols && is_mem_full))) { ESP_DRAM_LOGE(TAG, "encoding artifacts can't exceed hw memory block for loop transmission"); } }