linux/drivers/usb/host/ehci-mem.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright (c) 2001 by David Brownell
 */

/* this file is part of ehci-hcd.c */

/*-------------------------------------------------------------------------*/

/*
 * There's basically three types of memory:
 *	- data used only by the HCD ... kmalloc is fine
 *	- async and periodic schedules, shared by HC and HCD ... these
 *	  need to use dma_pool or dma_alloc_coherent
 *	- driver buffers, read/written by HC ... single shot DMA mapped
 *
 * There's also "register" data (e.g. PCI or SOC), which is memory mapped.
 * No memory seen by this driver is pageable.
 */

/*-------------------------------------------------------------------------*/

/* Allocate the key transfer structures from the previously allocated pool */

static inline void ehci_qtd_init(struct ehci_hcd *ehci, struct ehci_qtd *qtd,
				  dma_addr_t dma)
{ … }

static struct ehci_qtd *ehci_qtd_alloc (struct ehci_hcd *ehci, gfp_t flags)
{ … }

static inline void ehci_qtd_free (struct ehci_hcd *ehci, struct ehci_qtd *qtd)
{ … }


static void qh_destroy(struct ehci_hcd *ehci, struct ehci_qh *qh)
{ … }

static struct ehci_qh *ehci_qh_alloc (struct ehci_hcd *ehci, gfp_t flags)
{ … }

/*-------------------------------------------------------------------------*/

/* The queue heads and transfer descriptors are managed from pools tied
 * to each of the "per device" structures.
 * This is the initialisation and cleanup code.
 */

static void ehci_mem_cleanup (struct ehci_hcd *ehci)
{ … }

/* remember to add cleanup code (above) if you add anything here */
static int ehci_mem_init (struct ehci_hcd *ehci, gfp_t flags)
{ … }