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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/usb/host/ohci-mem.c
Initial import
Diffstat (limited to 'drivers/usb/host/ohci-mem.c')
-rw-r--r--drivers/usb/host/ohci-mem.c139
1 files changed, 139 insertions, 0 deletions
diff --git a/drivers/usb/host/ohci-mem.c b/drivers/usb/host/ohci-mem.c
new file mode 100644
index 000000000..c9e315c68
--- /dev/null
+++ b/drivers/usb/host/ohci-mem.c
@@ -0,0 +1,139 @@
+/*
+ * 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_LIST_HEAD(&ohci->eds_in_use);
+}
+
+/*-------------------------------------------------------------------------*/
+
+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);
+}
+