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    SubjectRe: [PATCH 8/8] phy: add driver for TI TUSB1210 ULPI PHY
    Hi Heikki,

    Sorry I am starting a new branch on this thread.
    I need to go back to another topic on this same patch.

    On Fri, Jan 23, 2015 at 05:12:58PM +0200, Heikki Krogerus wrote:
    > TUSB1210 ULPI PHY has vendor specific register for eye
    > diagram tuning. On some platforms the system firmware has
    > set optimized value to it. In order to not loose the
    > optimized value, the driver stores it during probe and
    > restores it every time the PHY is powered back on.
    >
    > Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
    > Cc: Kishon Vijay Abraham I <kishon@ti.com>
    > ---

    [snip]

    > + /* Store initial eye diagram optimisation value */
    > + ret = ulpi_read(ulpi, TUSB1210_VENDOR_SPECIFIC2);

    We can't rely on eye diagram optimization value here. It's possible the
    phy went through reset (e.g. module unloading/loading).
    We need a more consistent method. Could we use _DSD instead? That would
    be more compatible with DT too.

    Br, David

    > + if (ret < 0)
    > + return ret;
    > +
    > + tusb->eye_diagram_tuning = ret;
    > +
    > + tusb->phy = ulpi_phy_create(ulpi, &phy_ops);
    > + if (IS_ERR(tusb->phy))
    > + return PTR_ERR(tusb->phy);
    > +
    > + tusb->ulpi = ulpi;
    > +
    > + phy_set_drvdata(tusb->phy, tusb);
    > + ulpi_set_drvdata(ulpi, tusb);
    > + return 0;
    > +}
    > +


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