From: Florian Fainelli <f.faine...@gmail.com> Date: Fri, 24 Apr 2015 09:19:55 -0700
> On 24/04/15 09:01, David Miller wrote: >> From: Florian Fainelli <f.faine...@gmail.com> >> Date: Fri, 24 Apr 2015 08:56:34 -0700 >> >>> On 24/04/15 08:04, David Miller wrote: >>>> From: Vivien Didelot <vivien.dide...@savoirfairelinux.com> >>>> Date: Wed, 22 Apr 2015 13:06:54 -0400 >>>> >>>>> Some systems using mdio-gpio may use gpio on message based busses, which >>>>> require sleeping (e.g. gpio from an I2C I/O expander). >>>>> >>>>> Since this driver does not use IRQ handler, it is safe to use the >>>>> _cansleep suffixed gpio accessors. >>>>> >>>>> Signed-off-by: Vivien Didelot <vivien.dide...@savoirfairelinux.com> >>>> >>>> Since this is down underneath the layer of an MII bus, you cannot >>>> universally say that these routines are always called in a sleepable >>>> context. >>>> >>>> The PHY layer, and the driver itself above that, might call these >>>> routines from timers, interruptes etc. >>> >>> The PHY library calls these routines from its state machine workqueue >>> for that reason, or from process context (when invoked via ethtool >>> ioctl). The only special case is phy_mac_interrupt() which is callable >>> from interrupt context, but schedules the state machine workqueue anyway >>> to circumvent the "in-interrupt" context. >>> >>> If we were not doing that, there would be a number of things broken, for >>> instance the per-MDIO bus mutex would not protect us from anything. >> >> Does the link state polling timer use a workqueue in this manner as >> well? > > Yes, the state machine re-schedules its own delayed workqueue at the end > of its state processing, no timer/hrtimer is used. Ok, thanks for explaining. I'm apply this patch, therefore, thanks. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
