dwc_otg_hcd Struct Reference

This structure holds the state of the HCD, including the non-periodic and periodic schedules. More...

#include <dwc_otg_hcd.h>

Data Fields
dwc_otg_device *	otg_dev
	The DWC otg device pointer.
dwc_otg_core_if_t *	core_if
	DWC OTG Core Interface Layer.
dwc_otg_hcd_function_ops *	fops
	Function HCD driver callbacks.
dwc_otg_hcd::dwc_otg_hcd_internal_flags	flags
	Internal DWC HCD Flags.
dwc_list_link_t	non_periodic_sched_inactive
	Inactive items in the non-periodic schedule.
dwc_list_link_t	non_periodic_sched_active
	Active items in the non-periodic schedule.
dwc_list_link_t *	non_periodic_qh_ptr
	Pointer to the next Queue Head to process in the active non-periodic schedule.
dwc_list_link_t	periodic_sched_inactive
	Inactive items in the periodic schedule.
dwc_list_link_t	periodic_sched_ready
	List of periodic QHs that are ready for execution in the next frame, but have not yet been assigned to host channels.
dwc_list_link_t	periodic_sched_assigned
	List of periodic QHs to be executed in the next frame that are assigned to host channels.
dwc_list_link_t	periodic_sched_queued
	List of periodic QHs that have been queued for execution.
uint16_t	periodic_usecs
	Total bandwidth claimed so far for periodic transfers.
uint16_t	frame_number
	Frame number read from the core at SOF.
uint16_t	periodic_qh_count
	Count of periodic QHs, if using several eps.
hc_list	free_hc_list
	Free host channels in the controller.
int	periodic_channels
	Number of host channels assigned to periodic transfers.
int	non_periodic_channels
	Number of host channels assigned to non-periodic transfers.
dwc_hc *	hc_ptr_array [MAX_EPS_CHANNELS]
	Array of pointers to the host channel descriptors.
uint8_t *	status_buf
	Buffer to use for any data received during the status phase of a control transfer.
dma_addr_t	status_buf_dma
	DMA address for status_buf.
dwc_timer_t *	conn_timer
	Connection timer.
dwc_tasklet_t *	reset_tasklet
dwc_spinlock_t *	lock
void *	priv
	Private data that could be used by OS wrapper.
uint8_t	otg_port
uint32_t *	frame_list
	Frame List.
dma_addr_t	frame_list_dma
	Frame List DMA address.

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Detailed Description

This structure holds the state of the HCD, including the non-periodic and periodic schedules.

Definition at line 373 of file dwc_otg_hcd.h.

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Field Documentation

dwc_list_link_t dwc_otg_hcd::non_periodic_sched_inactive

Inactive items in the non-periodic schedule. This is a list of Queue Heads. Transfers associated with these Queue Heads are not currently assigned to a host channel. Definition at line 402 of file dwc_otg_hcd.h.

dwc_list_link_t dwc_otg_hcd::non_periodic_sched_active

Active items in the non-periodic schedule. This is a list of Queue Heads. Transfers associated with these Queue Heads are currently assigned to a host channel. Definition at line 409 of file dwc_otg_hcd.h.

dwc_list_link_t* dwc_otg_hcd::non_periodic_qh_ptr

Pointer to the next Queue Head to process in the active non-periodic schedule. Definition at line 415 of file dwc_otg_hcd.h.

dwc_list_link_t dwc_otg_hcd::periodic_sched_inactive

Inactive items in the periodic schedule. This is a list of QHs for periodic transfers that are _not_ scheduled for the next frame. Each QH in the list has an interval counter that determines when it needs to be scheduled for execution. This scheduling mechanism allows only a simple calculation for periodic bandwidth used (i.e. must assume that all periodic transfers may need to execute in the same frame). However, it greatly simplifies scheduling and should be sufficient for the vast majority of OTG hosts, which need to connect to a small number of peripherals at one time. Items move from this list to periodic_sched_ready when the QH interval counter is 0 at SOF. Definition at line 431 of file dwc_otg_hcd.h.

dwc_list_link_t dwc_otg_hcd::periodic_sched_ready

List of periodic QHs that are ready for execution in the next frame, but have not yet been assigned to host channels. Items move from this list to periodic_sched_assigned as host channels become available during the current frame. Definition at line 440 of file dwc_otg_hcd.h.

dwc_list_link_t dwc_otg_hcd::periodic_sched_assigned

List of periodic QHs to be executed in the next frame that are assigned to host channels. Items move from this list to periodic_sched_queued as the transactions for the QH are queued to the DWC_otg controller. Definition at line 449 of file dwc_otg_hcd.h.

dwc_list_link_t dwc_otg_hcd::periodic_sched_queued

List of periodic QHs that have been queued for execution. Items move from this list to either periodic_sched_inactive or periodic_sched_ready when the channel associated with the transfer is released. If the interval for the QH is 1, the item moves to periodic_sched_ready because it must be rescheduled for the next frame. Otherwise, the item moves to periodic_sched_inactive. Definition at line 460 of file dwc_otg_hcd.h.

uint16_t dwc_otg_hcd::periodic_usecs

Total bandwidth claimed so far for periodic transfers. This value is in microseconds per (micro)frame. The assumption is that all periodic transfers may occur in the same (micro)frame. Definition at line 467 of file dwc_otg_hcd.h.

uint16_t dwc_otg_hcd::frame_number

Frame number read from the core at SOF. The value ranges from 0 to DWC_HFNUM_MAX_FRNUM. Definition at line 473 of file dwc_otg_hcd.h.

uint16_t dwc_otg_hcd::periodic_qh_count

Count of periodic QHs, if using several eps. For SOF enable/disable. Definition at line 478 of file dwc_otg_hcd.h.

struct hc_list dwc_otg_hcd::free_hc_list

Free host channels in the controller. This is a list of dwc_hc_t items. Definition at line 484 of file dwc_otg_hcd.h.

int dwc_otg_hcd::periodic_channels

Number of host channels assigned to periodic transfers. Currently assuming that there is a dedicated host channel for each periodic transaction and at least one host channel available for non-periodic transactions. Definition at line 491 of file dwc_otg_hcd.h.

int dwc_otg_hcd::non_periodic_channels

Number of host channels assigned to non-periodic transfers. Definition at line 496 of file dwc_otg_hcd.h.

struct dwc_hc* dwc_otg_hcd::hc_ptr_array[MAX_EPS_CHANNELS]

Array of pointers to the host channel descriptors. Allows accessing a host channel descriptor given the host channel number. This is useful in interrupt handlers. Definition at line 503 of file dwc_otg_hcd.h.

uint8_t* dwc_otg_hcd::status_buf

Buffer to use for any data received during the status phase of a control transfer. Normally no data is transferred during the status phase. This buffer is used as a bit bucket. Definition at line 510 of file dwc_otg_hcd.h.

dma_addr_t dwc_otg_hcd::status_buf_dma

DMA address for status_buf. Definition at line 515 of file dwc_otg_hcd.h.

dwc_timer_t* dwc_otg_hcd::conn_timer

Connection timer. An OTG host must display a message if the device does not connect. Started when the VBus power is turned on via sysfs attribute "buspower". Definition at line 523 of file dwc_otg_hcd.h.

void* dwc_otg_hcd::priv

Private data that could be used by OS wrapper. Definition at line 534 of file dwc_otg_hcd.h.

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The documentation for this struct was generated from the following file:

• dwc_otg_hcd.h

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