STRUCT CDNSP_DEVICE(9)

💫 NAME 💫

okay so this is the struct cdnsp_device(9) page from the Kernel API Manual, bestie — and it’s literally the whole USB device vibe in one struct.

struct cdnsp_device — represent USB device. periodt 💅

🌸 SYNOPSIS 🌸

       struct cdnsp_device {
           struct device *dev;
           struct usb_gadget gadget;
           struct usb_gadget_driver *gadget_driver;
           unsigned int irq;
           void __iomem *regs;
           struct cdnsp_cap_regs __iomem *cap_regs;
           struct cdnsp_op_regs __iomem *op_regs;
           struct cdnsp_run_regs __iomem *run_regs;
           struct cdnsp_doorbell_array __iomem *dba;
           struct cdnsp_intr_reg __iomem *ir_set;
           struct cdnsp_20port_cap __iomem *port20_regs;
           struct cdnsp_3xport_cap __iomem *port3x_regs;
           struct cdnsp_rev_cap __iomem *rev_cap;
           __u32 hcs_params1;
           __u32 hcs_params3;
           __u32 hcc_params;
         #define RTL_REVISION_NEW_LPM 0x2700;
           __u32 rtl_revision;
           spinlock_t lock;
           struct usb_ctrlrequest setup;
           struct cdnsp_request ep0_preq;
           enum cdnsp_ep0_stage ep0_stage;
           u8 three_stage_setup;
           u8 ep0_expect_in;
           u8 setup_id;
           u8 setup_speed;
           void *setup_buf;
           u8 device_address;
           int may_wakeup;
           u16 hci_version;
           struct cdnsp_device_context_array *dcbaa;
           struct cdnsp_ring *cmd_ring;
           struct cdnsp_command cmd;
           struct cdnsp_ring *event_ring;
           struct cdnsp_erst erst;
           int slot_id;
           struct cdnsp_container_ctx out_ctx;
           struct cdnsp_container_ctx in_ctx;
           struct cdnsp_ep eps[CDNSP_ENDPOINTS_NUM];
           u8 usb2_hw_lpm_capable:1;
           u8 u1_allowed:1;
           u8 u2_allowed:1;
           struct dma_pool *device_pool;
           struct dma_pool *segment_pool;
         #define CDNSP_STATE_HALTED              BIT(1);
         #define CDNSP_STATE_DYING               BIT(2);
         #define CDNSP_STATE_DISCONNECT_PENDING  BIT(3);
         #define CDNSP_WAKEUP_PENDING            BIT(4);
           unsigned int cdnsp_state;
           unsigned int link_state;
           struct cdnsp_port usb2_port;
           struct cdnsp_port eusb_port;
           struct cdnsp_port usb3_port;
           struct cdnsp_port *active_port;
           u16 test_mode;
        };

no cap, this is a big struct — but every field is a little puzzle piece and we’re gonna go through all of them 💖

✨ Members ✨

• dev — pointer to the device structure associated with this controller.
• gadget — device side representation of the peripheral controller.
• gadget_driver — pointer to the gadget driver.
• irq — IRQ line number used by device side.
• regs — IO device memory.
• cap_regs — capability registers.
• op_regs — operational registers.
• run_regs — runtime registers.
• dba — device base address register.
• ir_set — current interrupter register set.
• port20_regs — Port 2.0 Peripheral Configuration Registers.
• port3x_regs — USB3.x Port Peripheral Configuration Registers.
• rev_cap — Controller Capabilities Registers.
• hcs_params1 — cached register copies of read-only HCSPARAMS1.
• hcc_params — cached register copies of read-only HCCPARAMS1.
• rtl_revision — cached controller rtl revision.
• lock — lock used in interrupt thread context.
• setup — temporary buffer for setup packet.
• ep0_preq — internal allocated request used during enumeration.
• ep0_stage — ep0 stage during enumeration process.
• three_stage_setup — three state or two state setup.
• ep0_expect_in — data IN expected for control transfer.
• setup_id — setup identifier. setup_speed — speed detected for current SETUP packet.
• setup_buf — buffer for SETUP packet.
• device_address — current device address.
• may_wakeup — remote wakeup enabled/disabled.
• hci_version — device controller version.
• dcbaa — Device context base address array.
• cmd_ring — Command ring.
• cmd — represent all what is needed to issue command on Command Ring.
• event_ring — Event ring.
• erst — Event Ring Segment table.
• slot_id — current Slot ID. Should be 0 or 1.
• out_ctx — output context.
• in_ctx — input context.
• eps — array of endpoints object associated with device.
• usb2_hw_lpm_capable — hardware lpm is enabled; 👀
• u1_allowed — allow device transition to U1 state.
• u2_allowed — allow device transition to U2 state.
• device_pool — DMA pool for allocating input and output context.
• segment_pool — DMA pool for allocating new segments.
• cdnsp_state — current state of controller.
• link_state — current link state. usb2_port — Port USB 2.0. usb3_port — Port USB 3.0. active_port — current selected Port.
• test_mode — selected Test Mode.

🔮 SEE ALSO 🔮

Kernel file ./drivers/usb/cdns3/cdnsp-gadget.h has the whole squad, bestie:

• struct cdnsp_cap_regs(9)
• struct cdnsp_op_regs(9)
• struct cdnsp_port_regs(9)
• struct cdnsp_intr_reg(9)
• struct cdnsp_run_regs(9)
• struct cdnsp_rev_cap(9)
• struct cdnsp_doorbell_array(9)
• struct cdnsp_container_ctx(9)
• struct cdnsp_slot_ctx(9)
• struct cdnsp_ep_ctx(9)
• struct cdnsp_stream_info(9)
• struct cdnsp_ep(9)
• struct cdnsp_device_context_array(9)
• struct cdnsp_transfer_event(9)
• struct cdnsp_link_trb(9)
• struct cdnsp_event_cmd(9)
• struct cdnsp_segment(9)
• struct cdnsp_td(9)
• struct cdnsp_dequeue_state(9)
• struct cdnsp_ring(9)
• struct cdnsp_erst_entry(9)
• struct cdnsp_erst(9)
• struct cdnsp_request(9)
• struct cdnsp_port(9)
• next_request(9)

and that’s the whole page, bestie 🫶 source vibe is ./drivers/usb/cdns3, dated October 2026 — mwah 💋✨