STRUCT CDNS3_ENDPOINT(9)

🌸 NAME 🌸

okay so bestie, welcome to struct cdns3_endpoint — it's literally the extended device side representation of USB endpoint. that's the whole vibe. it's giving "the endpoint, but make it extra" 💅

✨ SYNOPSIS ✨

like, here's the whole fit, no cap:

struct cdns3_endpoint {
    struct usb_ep           endpoint;
    struct list_head        pending_req_list;
    struct list_head        deferred_req_list;
    struct list_head        wa2_descmiss_req_list;
    int wa2_counter;
    struct cdns3_trb        *trb_pool;
    dma_addr_t trb_pool_dma;
    struct cdns3_device     *cdns3_dev;
    char name[20];
  #define EP_ENABLED              BIT(0);
  #define EP_STALLED              BIT(1);
  #define EP_STALL_PENDING        BIT(2);
  #define EP_WEDGE                BIT(3);
  #define EP_TRANSFER_STARTED     BIT(4);
  #define EP_UPDATE_EP_TRBADDR    BIT(5);
  #define EP_PENDING_REQUEST      BIT(6);
  #define EP_RING_FULL            BIT(7);
  #define EP_CLAIMED              BIT(8);
  #define EP_DEFERRED_DRDY        BIT(9);
  #define EP_QUIRK_ISO_OUT_EN     BIT(10);
  #define EP_QUIRK_END_TRANSFER   BIT(11);
  #define EP_QUIRK_EXTRA_BUF_DET  BIT(12);
  #define EP_QUIRK_EXTRA_BUF_EN   BIT(13);
  #define EP_TDLCHK_EN            BIT(15);
  #define EP_CONFIGURED           BIT(16);
    u32 flags;
    struct cdns3_request    *descmis_req;
    u8 dir;
    u8 num;
    u8 type;
    u8 mult;
    u8 bMaxBurst;
    u16 wMaxPacketSize;
    int interval;
    int free_trbs;
    int num_trbs;
    int alloc_ring_size;
    u8 pcs;
    u8 ccs;
    int enqueue;
    int dequeue;
    u8 trb_burst_size;
    unsigned int            wa1_set:1;
    struct cdns3_trb        *wa1_trb;
    unsigned int            wa1_trb_index;
    unsigned int            wa1_cycle_bit:1;
    unsigned int            use_streams:1;
    unsigned int            prime_flag:1;
    u32 ep_sts_pending;
    u16 last_stream_id;
    u16 pending_tdl;
    unsigned int            stream_sg_idx;
 };

👑 Members 👑

bestie. buckle up. we're going member by member and i'm gonna make it make sense 🫶

• endpoint — the usb endpoint. yeah. that's it. the actual endpoint, in the flesh.
• pending_req_list — the list of requests that are queuing on the transfer ring. they're in line, they're waiting, they're being patient 💖
• deferred_req_list — the list of requests waiting for queuing on the transfer ring. so not even in line yet — they're in the waiting room of the waiting room 😭
• wa2_descmiss_req_list — the list of requests internally allocated by the driver. house-made, not user-submitted, iykyk.
• trb_pool — the transfer ring, aka an array of transaction buffers. it's the whole pool, babes 🏊
• trb_pool_dma — the dma address of that transfer ring. the pool's mailing address, basically.
• cdns3_dev — the device associated with this endpoint. they're linked. main character and their plus-one 💜
• name — a human readable name, e.g. ep1out. cute little nametag energy 🎀
• flags — specify the current state of endpoint. it's the mood ring. it's the vibe check. (all those EP_* defines up there? yeah, that's this.)
• descmis_req — internal transfer object used for getting data from on-chip buffer. heads up tho: it can happen only if the function driver doesn't send usb_request object on time. so like, this is the driver's backup plan. not the ideal timeline 🙈
• dir — endpoint direction. which way we goin'.
• num — endpoint number, and the range is exactly 1 - 15.
• type — set to bmAttributes & USB_ENDPOINT_XFERTYPE_MASK. yes, keep the exact expression, it's load-bearing ✨
• interval — interval between packets, used for ISOC endpoint. the rhythm section.
• free_trbs — number of free TRBs in transfer ring. how much room is left in the pool.
• num_trbs — number of all TRBs in transfer ring. the total headcount, not just the available ones.
• alloc_ring_size — size of the allocated TRB ring.
• pcs — producer cycle state.
• ccs — consumer cycle state. (pcs's other half, they're a duo 🦋)
• enqueue — enqueue index in transfer ring.
• dequeue — dequeue index in transfer ring. (they're literally the in-and-out of the same ring, obsessed.)
• trb_burst_size — number of burst used in trb.

ngl bestie, some of the members in that struct above don't get their own blurb in this section — that's just how the page is, so i'm not gonna make stuff up about them. the facts stay facts, periodt 💀

🦋 SEE ALSO 🦋

go read these next, they're all in the kernel file ./drivers/usb/cdns3/cdns3-gadget.h:

• struct cdns3_usb_regs(9)
• struct cdns3_trb(9)
• struct cdns3_aligned_buf(9)
• struct cdns3_request(9)
• struct cdns3_device(9)

okay that's the whole page!! this one came from ./drivers/usb/cdns3, it's dated October 2026, and it lives in the Kernel API Manual as struct cdns3_endpoint(9). slay, you read the whole thing, i'm so proud of you 🥹💖✨