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| author | Stefan Richter <stefanr@s5r6.in-berlin.de> | 2011-06-21 15:24:26 +0200 |
|---|---|---|
| committer | Stefan Richter <stefanr@s5r6.in-berlin.de> | 2011-07-09 17:12:08 +0200 |
| commit | b14c369d87d7fbf120ad21919d34a8f1290290f1 (patch) | |
| tree | 37947e2121f1c205ee4295c8c8c559d9f7693f87 /drivers/firewire/ohci.c | |
| parent | firewire: ohci: reduce potential context_stop latency (diff) | |
| download | linux-b14c369d87d7fbf120ad21919d34a8f1290290f1.tar.xz linux-b14c369d87d7fbf120ad21919d34a8f1290290f1.zip | |
firewire: ohci: add a comment on PHY reg access serialization
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Diffstat (limited to 'drivers/firewire/ohci.c')
| -rw-r--r-- | drivers/firewire/ohci.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c index 3b6f3429fb4a..a818dc834690 100644 --- a/drivers/firewire/ohci.c +++ b/drivers/firewire/ohci.c @@ -513,6 +513,12 @@ static inline void flush_writes(const struct fw_ohci *ohci) reg_read(ohci, OHCI1394_Version); } +/* + * Beware! read_phy_reg(), write_phy_reg(), update_phy_reg(), and + * read_paged_phy_reg() require the caller to hold ohci->phy_reg_mutex. + * In other words, only use ohci_read_phy_reg() and ohci_update_phy_reg() + * directly. Exceptions are intrinsically serialized contexts like pci_probe. + */ static int read_phy_reg(struct fw_ohci *ohci, int addr) { u32 val; |