From 032de0b0df92162aa579eda986145e3756a29a6c Mon Sep 17 00:00:00 2001 From: Tobi Date: Thu, 30 Oct 2025 12:21:21 +0100 Subject: [PATCH] Video Class: New callback function added which allows to generate frame data on the fly - If buffer is set to NULL, the callback will request payload data from a user function. This allows to work with dynamic content on platforms which are not able to hold a whole frame in memory. - Callback uses the same "weak" linking as other callbacks for this class. --- src/class/video/video_device.c | 18 +++++++++++++++--- src/class/video/video_device.h | 10 ++++++++++ 2 files changed, 25 insertions(+), 3 deletions(-) diff --git a/src/class/video/video_device.c b/src/class/video/video_device.c index 5c00cc358..00f192af6 100644 --- a/src/class/video/video_device.c +++ b/src/class/video/video_device.c @@ -214,6 +214,14 @@ TU_ATTR_WEAK int tud_video_commit_cb(uint_fast8_t ctl_idx, uint_fast8_t stm_idx, return VIDEO_ERROR_NONE; } +TU_ATTR_WEAK void tud_video_prepare_payload_cb(uint_fast8_t ctl_idx, uint_fast8_t stm_idx, void* payload_buf, size_t payload_size, size_t offset) { + (void) ctl_idx; + (void) stm_idx; + (void) payload_buf; + (void) payload_size; + (void) offset; +} + //--------------------------------------------------------------------+ // //--------------------------------------------------------------------+ @@ -860,7 +868,11 @@ static uint_fast16_t _prepare_in_payload(videod_streaming_interface_t *stm, uint } TU_ASSERT(pkt_len >= hdr_len); uint_fast16_t data_len = pkt_len - hdr_len; - memcpy(&ep_buf[hdr_len], stm->buffer + stm->offset, data_len); + if (stm->buffer) { + memcpy(&ep_buf[hdr_len], stm->buffer + stm->offset, data_len); + } else { + tud_video_prepare_payload_cb(stm->index_vc, stm->index_vs, &ep_buf[hdr_len], data_len, stm->offset); + } stm->offset += data_len; remaining -= data_len; if (!remaining) { @@ -1235,11 +1247,11 @@ bool tud_video_n_frame_xfer(uint_fast8_t ctl_idx, uint_fast8_t stm_idx, void *bu TU_ASSERT(ctl_idx < CFG_TUD_VIDEO); TU_ASSERT(stm_idx < CFG_TUD_VIDEO_STREAMING); - if (!buffer || !bufsize) return false; + if (!bufsize) return false; videod_streaming_interface_t *stm = _get_instance_streaming(ctl_idx, stm_idx); videod_streaming_epbuf_t *stm_epbuf = &_videod_streaming_epbuf[ctl_idx]; - if (!stm || !stm->desc.ep[0] || stm->buffer) return false; + if (!stm || !stm->desc.ep[0] || stm->bufsize) return false; if (stm->state == VS_STATE_PROBING) return false; /* Find EP address */ diff --git a/src/class/video/video_device.h b/src/class/video/video_device.h index 2b41c3bfe..b3094dd81 100644 --- a/src/class/video/video_device.h +++ b/src/class/video/video_device.h @@ -83,6 +83,16 @@ int tud_video_power_mode_cb(uint_fast8_t ctl_idx, uint8_t power_mod); int tud_video_commit_cb(uint_fast8_t ctl_idx, uint_fast8_t stm_idx, video_probe_and_commit_control_t const *parameters); +/** Invoked if buffer is set to NULL (allows bufferless on the fly data generation) + * + * @param[in] ctl_idx Destination control interface index + * @param[in] stm_idx Destination streaming interface index + * @param[out] payload_buf Payload storage buffer (target buffer for requested data) + * @param[in] payload_size Size of payload_buf (requested data size) + * @param[in] offset Current byte offset relative to given bufsize from tud_video_n_frame_xfer (framesize) + * @return video_error_code_t */ +void tud_video_prepare_payload_cb(uint_fast8_t ctl_idx, uint_fast8_t stm_idx, void* payload_buf, size_t payload_size, size_t offset); + //--------------------------------------------------------------------+ // INTERNAL USBD-CLASS DRIVER API //--------------------------------------------------------------------+