On 18 June 2012 13:41, Tomi Valkeinen <tomi.valkeinen@xxxxxx> wrote: >> >> Explicitly maintaining HDMI phy power state using a flag is prone to >> race and un-necessary when we have a zero-cost alternative of checking >> the state before trying to set it. > > Why would reading the value from the register be any less racy than > keeping it in memory? > Racy in the sense that h/w doesn't always hop states according to what a "state" variable would expect it to. Also in this case, phy_tx_enabled modification is unprotected in ti_hdmi_4xxx_phy_disable(). BTW, coming to think about it, I am not sure what we need the spin_lock_irqsave() protection for in hdmi_check_hpd_state() ? It can't control HPD gpio state change and hdmi_set_phy_pwr() seems too expensive and is already unprotected elsewhere. > And reading from memory is probably much faster > than reading from an HDMI register, so I'm not sure what you mean with > zero-cost. > Zero-cost in terms of space and bother :) > But I guess it is simpler, so in that sense the patch is ok. But please > revise the description. > OK, will do. Thanks. -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
