linux/drivers/usb/host/ohci-mem.c
Michael Hanselmann d576bb9f27 USB: Fix NEC OHCI chip silicon bug
This patch fixes a silicon bug in some NEC OHCI chips. The bug appears
at random times and is very, very difficult to reproduce. Without the
following patch, Linux would shut the chip and its associated devices
down. In Apple PowerBooks this leads to an unusable keyboard and mouse
(SSH still working). The idea of restarting the chip is taken from
public Darwin code.

Signed-off-by: Michael Hanselmann <linux-kernel@hansmi.ch>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-12 16:34:29 -07:00

139 lines
3.4 KiB
C

/*
* OHCI HCD (Host Controller Driver) for USB.
*
* (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at>
* (C) Copyright 2000-2002 David Brownell <dbrownell@users.sourceforge.net>
*
* This file is licenced under the GPL.
*/
/*-------------------------------------------------------------------------*/
/*
* OHCI deals with 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 ... the hcd glue or the
* device driver provides us with dma addresses
*
* There's also "register" data, which is memory mapped.
* No memory seen by this driver (or any HCD) may be paged out.
*/
/*-------------------------------------------------------------------------*/
static void ohci_hcd_init (struct ohci_hcd *ohci)
{
ohci->next_statechange = jiffies;
spin_lock_init (&ohci->lock);
INIT_LIST_HEAD (&ohci->pending);
INIT_WORK (&ohci->nec_work, ohci_quirk_nec_worker);
}
/*-------------------------------------------------------------------------*/
static int ohci_mem_init (struct ohci_hcd *ohci)
{
ohci->td_cache = dma_pool_create ("ohci_td",
ohci_to_hcd(ohci)->self.controller,
sizeof (struct td),
32 /* byte alignment */,
0 /* no page-crossing issues */);
if (!ohci->td_cache)
return -ENOMEM;
ohci->ed_cache = dma_pool_create ("ohci_ed",
ohci_to_hcd(ohci)->self.controller,
sizeof (struct ed),
16 /* byte alignment */,
0 /* no page-crossing issues */);
if (!ohci->ed_cache) {
dma_pool_destroy (ohci->td_cache);
return -ENOMEM;
}
return 0;
}
static void ohci_mem_cleanup (struct ohci_hcd *ohci)
{
if (ohci->td_cache) {
dma_pool_destroy (ohci->td_cache);
ohci->td_cache = NULL;
}
if (ohci->ed_cache) {
dma_pool_destroy (ohci->ed_cache);
ohci->ed_cache = NULL;
}
}
/*-------------------------------------------------------------------------*/
/* ohci "done list" processing needs this mapping */
static inline struct td *
dma_to_td (struct ohci_hcd *hc, dma_addr_t td_dma)
{
struct td *td;
td_dma &= TD_MASK;
td = hc->td_hash [TD_HASH_FUNC(td_dma)];
while (td && td->td_dma != td_dma)
td = td->td_hash;
return td;
}
/* TDs ... */
static struct td *
td_alloc (struct ohci_hcd *hc, gfp_t mem_flags)
{
dma_addr_t dma;
struct td *td;
td = dma_pool_alloc (hc->td_cache, mem_flags, &dma);
if (td) {
/* in case hc fetches it, make it look dead */
memset (td, 0, sizeof *td);
td->hwNextTD = cpu_to_hc32 (hc, dma);
td->td_dma = dma;
/* hashed in td_fill */
}
return td;
}
static void
td_free (struct ohci_hcd *hc, struct td *td)
{
struct td **prev = &hc->td_hash [TD_HASH_FUNC (td->td_dma)];
while (*prev && *prev != td)
prev = &(*prev)->td_hash;
if (*prev)
*prev = td->td_hash;
else if ((td->hwINFO & cpu_to_hc32(hc, TD_DONE)) != 0)
ohci_dbg (hc, "no hash for td %p\n", td);
dma_pool_free (hc->td_cache, td, td->td_dma);
}
/*-------------------------------------------------------------------------*/
/* EDs ... */
static struct ed *
ed_alloc (struct ohci_hcd *hc, gfp_t mem_flags)
{
dma_addr_t dma;
struct ed *ed;
ed = dma_pool_alloc (hc->ed_cache, mem_flags, &dma);
if (ed) {
memset (ed, 0, sizeof (*ed));
INIT_LIST_HEAD (&ed->td_list);
ed->dma = dma;
}
return ed;
}
static void
ed_free (struct ohci_hcd *hc, struct ed *ed)
{
dma_pool_free (hc->ed_cache, ed, ed->dma);
}