[PATCH net-next 1/4] drivers: net: xgene-v2: Add MDIO support
Keyur Chudgar
kchudgar at apm.com
Tue Mar 21 17:08:49 PDT 2017
Hi Iyappan,
I agree with Andrew.
Let's re-post the patch after addressing Andrew's comment.
Thanks,
Keyur
> -----Original Message-----
> From: Iyappan Subramanian [mailto:isubramanian at apm.com]
> Sent: Tuesday, March 21, 2017 4:19 PM
> To: Andrew Lunn
> Cc: David Miller; netdev; Florian Fainelli; David Laight; linux-arm-
> kernel at lists.infradead.org; patches; Keyur Chudgar
> Subject: Re: [PATCH net-next 1/4] drivers: net: xgene-v2: Add MDIO
> support
>
> On Tue, Mar 21, 2017 at 1:35 PM, Andrew Lunn <andrew at lunn.ch> wrote:
> >> @@ -511,9 +512,9 @@ static int xge_close(struct net_device *ndev) {
> >> struct xge_pdata *pdata = netdev_priv(ndev);
> >>
> >> - netif_carrier_off(ndev);
> >> netif_stop_queue(ndev);
> >> xge_mac_disable(pdata);
> >> + phy_stop(ndev->phydev);
> >>
> >> xge_intr_disable(pdata);
> >> xge_free_irq(ndev);
> >> @@ -683,9 +684,14 @@ static int xge_probe(struct platform_device
> *pdev)
> >> if (ret)
> >> goto err;
> >>
> >> + spin_lock_init(&pdata->mdio_lock);
> >> +
> >
> > ...
> >
> >> +static int xge_mdio_write(struct mii_bus *bus, int phy_id, int reg,
> >> +u16 data) {
> >> + struct xge_pdata *pdata = bus->priv;
> >> + u32 done, val = 0;
> >> + u8 wait = 10;
> >> + int ret = 0;
> >> +
> >> + spin_lock(&pdata->mdio_lock);
> >> +
> >> + SET_REG_BITS(&val, PHY_ADDR, phy_id);
> >> + SET_REG_BITS(&val, REG_ADDR, reg);
> >> + xge_wr_csr(pdata, MII_MGMT_ADDRESS, val);
> >> +
> >> + xge_wr_csr(pdata, MII_MGMT_CONTROL, data);
> >> + do {
> >> + usleep_range(5, 10);
> >> + done = xge_rd_csr(pdata, MII_MGMT_INDICATORS);
> >> + } while ((done & MII_MGMT_BUSY) && wait--);
> >> +
> >> + if (done & MII_MGMT_BUSY) {
> >> + dev_err(&bus->dev, "MII_MGMT write failed\n");
> >> + ret = -ETIMEDOUT;
> >> + }
> >> +
> >> + spin_unlock(&pdata->mdio_lock);
> >> +
> >> + return ret;
> >> +}
> >> +
> >> +static int xge_mdio_read(struct mii_bus *bus, int phy_id, int reg)
> {
> >> + struct xge_pdata *pdata = bus->priv;
> >> + u32 data, done, val = 0;
> >> + u8 wait = 10;
> >> +
> >> + spin_lock(&pdata->mdio_lock);
> >> +
> >
> > Hi Iyappan
> >
> > Please could you explain what this lock is protecting which the
> > mii_bus mdio_lock in mdio_bus.c is not protecting?
>
> Hi Keyur,
>
> Please could you explain what this lock is protecting which the mii_bus
> mdio_lock in mdio_bus.c is not protecting?
>
> I agree with him. Actually there is a mutex on mdio_bus. So the mdio
> bus read and write are locked. we don't need the lock.
>
> Do you agree ?
>
>
> >
> > Thanks
> > Andrew
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