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authorArtem Bityutskiy <Artem.Bityutskiy@nokia.com>2011-03-25 17:41:20 +0200
committerArtem Bityutskiy <Artem.Bityutskiy@nokia.com>2011-03-25 17:41:20 +0200
commit7bf7e370d5919112c223a269462cd0b546903829 (patch)
tree03ccc715239df14ae168277dbccc9d9cf4d8a2c8 /sound/firewire/lib.c
parent68b1a1e786f29c900fa1c516a402e24f0ece622a (diff)
parentd39dd11c3e6a7af5c20bfac40594db36cf270f42 (diff)
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into for-linus-1
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6: (9356 commits) [media] rc: update for bitop name changes fs: simplify iget & friends fs: pull inode->i_lock up out of writeback_single_inode fs: rename inode_lock to inode_hash_lock fs: move i_wb_list out from under inode_lock fs: move i_sb_list out from under inode_lock fs: remove inode_lock from iput_final and prune_icache fs: Lock the inode LRU list separately fs: factor inode disposal fs: protect inode->i_state with inode->i_lock lib, arch: add filter argument to show_mem and fix private implementations SLUB: Write to per cpu data when allocating it slub: Fix debugobjects with lockless fastpath autofs4: Do not potentially dereference NULL pointer returned by fget() in autofs_dev_ioctl_setpipefd() autofs4 - remove autofs4_lock autofs4 - fix d_manage() return on rcu-walk autofs4 - fix autofs4_expire_indirect() traversal autofs4 - fix dentry leak in autofs4_expire_direct() autofs4 - reinstate last used update on access vfs - check non-mountpoint dentry might block in __follow_mount_rcu() ... NOTE! This merge commit was created to fix compilation error. The block tree was merged upstream and removed the 'elv_queue_empty()' function which the new 'mtdswap' driver is using. So a simple merge of the mtd tree with upstream does not compile. And the mtd tree has already be published, so re-basing it is not an option. To fix this unfortunate situation, I had to merge upstream into the mtd-2.6.git tree without committing, put the fixup patch on top of this, and then commit this. The result is that we do not have commits which do not compile. In other words, this merge commit "merges" 3 things: the MTD tree, the upstream tree, and the fixup patch.
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 000000000000..4750cea2210e
--- /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");