firewire: ohci: add a comment on PHY reg access serialization

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This commit is contained in:
Stefan Richter 2011-06-21 15:24:26 +02:00
parent 9ef28ccd59
commit b14c369d87

View File

@ -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;