author: B.J. Buchalter <bj@mhlabs.com> 2011-05-02 13:33:42 -0400
committer: Stefan Richter <stefanr@s5r6.in-berlin.de> 2011-05-02 22:55:22 +0200
commit: 2e053a27d9d5ad5e0831e002cbf8043836fb2060
parent: 115881d395959b75c8c3bb94913f2ce869b8aa7a
Commit Summary:
Diffstat:
1 file changed, 24 insertions, 14 deletions
diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c
index f903d7b6f34a..23d1468ad253 100644
--- a/drivers/firewire/ohci.c
+++ b/drivers/firewire/ohci.c
@@ -2199,7 +2199,6 @@ static int ohci_set_config_rom(struct fw_card *card,
{
struct fw_ohci *ohci;
unsigned long flags;
- int ret = -EBUSY;
__be32 *next_config_rom;
dma_addr_t uninitialized_var(next_config_rom_bus);
@@ -2240,22 +2239,37 @@ static int ohci_set_config_rom(struct fw_card *card,
spin_lock_irqsave(&ohci->lock, flags);
+ /*
+ * If there is not an already pending config_rom update,
+ * push our new allocation into the ohci->next_config_rom
+ * and then mark the local variable as null so that we
+ * won't deallocate the new buffer.
+ *
+ * OTOH, if there is a pending config_rom update, just
+ * use that buffer with the new config_rom data, and
+ * let this routine free the unused DMA allocation.
+ */
+
if (ohci->next_config_rom == NULL) {
ohci->next_config_rom = next_config_rom;
ohci->next_config_rom_bus = next_config_rom_bus;
+ next_config_rom = NULL;
+ }
- copy_config_rom(ohci->next_config_rom, config_rom, length);
+ copy_config_rom(ohci->next_config_rom, config_rom, length);
- ohci->next_header = config_rom[0];
- ohci->next_config_rom[0] = 0;
+ ohci->next_header = config_rom[0];
+ ohci->next_config_rom[0] = 0;
- reg_write(ohci, OHCI1394_ConfigROMmap,
- ohci->next_config_rom_bus);
- ret = 0;
- }
+ reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
spin_unlock_irqrestore(&ohci->lock, flags);
+ /* If we didn't use the DMA allocation, delete it. */
+ if (next_config_rom != NULL)
+ dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
+ next_config_rom, next_config_rom_bus);
+
/*
* Now initiate a bus reset to have the changes take
* effect. We clean up the old config rom memory and DMA
@@ -2263,13 +2277,10 @@ static int ohci_set_config_rom(struct fw_card *card,
* controller could need to access it before the bus reset
* takes effect.
*/
- if (ret == 0)
- fw_schedule_bus_reset(&ohci->card, true, true);
- else
- dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
- next_config_rom, next_config_rom_bus);
- return ret;
+ fw_schedule_bus_reset(&ohci->card, true, true);
+
+ return 0;
}
static void ohci_send_request(struct fw_card *card, struct fw_packet *packet)