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authorLinus Torvalds <torvalds@linux-foundation.org>2011-03-18 10:46:37 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-03-18 10:46:37 -0700
commitd3e458d78167102cc961237cfceef6fffc80c0b3 (patch)
treee9195c1294daf053614e63ac52b0b44a28479017 /sound/firewire/lib.c
parentf2e1fbb5f2177227f71c4fc0491e531dd7acd385 (diff)
parentd351cf4603edb2a5bfa9a48d06c425511c63f2a3 (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6: (308 commits) ALSA: sound/pci/asihpi: check adapter index in hpi_ioctl ALSA: aloop - Fix possible IRQ lock inversion ALSA: sound/core: merge list_del()/list_add_tail() to list_move_tail() ALSA: ctxfi - use list_move() instead of list_del()/list_add() combination ALSA: firewire - msleep needs delay.h ALSA: firewire-lib, firewire-speakers: handle packet queueing errors ALSA: firewire-lib: allocate DMA buffer separately ALSA: firewire-lib: use no-info SYT for packets without SYT sample ALSA: add LaCie FireWire Speakers/Griffin FireWave Surround driver ALSA: hda - Remove an unused variable in patch_realtek.c ALSA: hda - pin-adc-mux-dmic auto-configuration of 92HD8X codecs ALSA: hda - fix digital mic selection in mixer on 92HD8X codecs ALSA: hda - Move default input-src selection to init part ALSA: hda - Initialize special cases for input src in init phase ALSA: ctxfi - Clear input settings before initialization ALSA: ctxfi - Fix SPDIF status retrieval ALSA: ctxfi - Fix incorrect SPDIF status bit mask ALSA: ctxfi - Fix microphone boost codes/comments ALSA: atiixp - Fix wrong time-out checks during ac-link reset ALSA: intel8x0m: append 'm' to "r_intel8x0" ...
Diffstat (limited to 'sound/firewire/lib.c')
-rw-r--r--sound/firewire/lib.c85
1 files changed, 85 insertions, 0 deletions
diff --git a/sound/firewire/lib.c b/sound/firewire/lib.c
new file mode 100644
index 00000000000..4750cea2210
--- /dev/null
+++ b/sound/firewire/lib.c
@@ -0,0 +1,85 @@
+/*
+ * miscellaneous helper functions
+ *
+ * Copyright (c) Clemens Ladisch <clemens@ladisch.de>
+ * Licensed under the terms of the GNU General Public License, version 2.
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/firewire.h>
+#include <linux/module.h>
+#include "lib.h"
+
+#define ERROR_RETRY_DELAY_MS 5
+
+/**
+ * rcode_string - convert a firewire result code to a string
+ * @rcode: the result
+ */
+const char *rcode_string(unsigned int rcode)
+{
+ static const char *const names[] = {
+ [RCODE_COMPLETE] = "complete",
+ [RCODE_CONFLICT_ERROR] = "conflict error",
+ [RCODE_DATA_ERROR] = "data error",
+ [RCODE_TYPE_ERROR] = "type error",
+ [RCODE_ADDRESS_ERROR] = "address error",
+ [RCODE_SEND_ERROR] = "send error",
+ [RCODE_CANCELLED] = "cancelled",
+ [RCODE_BUSY] = "busy",
+ [RCODE_GENERATION] = "generation",
+ [RCODE_NO_ACK] = "no ack",
+ };
+
+ if (rcode < ARRAY_SIZE(names) && names[rcode])
+ return names[rcode];
+ else
+ return "unknown";
+}
+EXPORT_SYMBOL(rcode_string);
+
+/**
+ * snd_fw_transaction - send a request and wait for its completion
+ * @unit: the driver's unit on the target device
+ * @tcode: the transaction code
+ * @offset: the address in the target's address space
+ * @buffer: input/output data
+ * @length: length of @buffer
+ *
+ * Submits an asynchronous request to the target device, and waits for the
+ * response. The node ID and the current generation are derived from @unit.
+ * On a bus reset or an error, the transaction is retried a few times.
+ * Returns zero on success, or a negative error code.
+ */
+int snd_fw_transaction(struct fw_unit *unit, int tcode,
+ u64 offset, void *buffer, size_t length)
+{
+ struct fw_device *device = fw_parent_device(unit);
+ int generation, rcode, tries = 0;
+
+ for (;;) {
+ generation = device->generation;
+ smp_rmb(); /* node_id vs. generation */
+ rcode = fw_run_transaction(device->card, tcode,
+ device->node_id, generation,
+ device->max_speed, offset,
+ buffer, length);
+
+ if (rcode == RCODE_COMPLETE)
+ return 0;
+
+ if (rcode_is_permanent_error(rcode) || ++tries >= 3) {
+ dev_err(&unit->device, "transaction failed: %s\n",
+ rcode_string(rcode));
+ return -EIO;
+ }
+
+ msleep(ERROR_RETRY_DELAY_MS);
+ }
+}
+EXPORT_SYMBOL(snd_fw_transaction);
+
+MODULE_DESCRIPTION("FireWire audio helper functions");
+MODULE_AUTHOR("Clemens Ladisch <clemens@ladisch.de>");
+MODULE_LICENSE("GPL v2");