Hi Claudiu, On Mon, Nov 26, 2018 at 8:22 PM Andrew Lunn <and...@lunn.ch> wrote: > > On Mon, Nov 26, 2018 at 02:46:01PM +0000, claudiu.bez...@microchip.com wrote: > > Hi Harini, > > > > On 26.11.2018 09:07, Harini Katakam wrote: > > > From: Harini Katakam <hari...@xilinx.com> > > > > > > Replace the while loop in MDIO read/write functions with a timeout. > > > In addition, add a check for MDIO bus busy before initiating a new > > > operation as well to make sure there is no ongoing MDIO operation. > > > > Is this MDIO bus busy check necessary? The caller of > > macb_mdio_read/macb_mdio_write locks the mdio bus mutex before calling it > > (e.g. mdiobus_read). > > Hi Claudiu > > It depends on the implementation. A write operation you could just > launch, but not wait for it to complete, allowing you to do other > stuff while the hardware is busy. For the next operation you then do > need to check the previous operation has completed. > > I've not checked it is actually implemented this way.
Yes, as Andrew mentioned, a previous MDIO bus operation cannot be assumed to be complete always - for ex., in case of a timeout. There is a chance that the MDIO bus bit is busy when mdio_read/write is called. Regards, Harini
