RE: [PATCH NET V6 1/2] net: phy: Add phy loopback support in net phy framework

[Madalin-cristian Bucur]

> -----Original Message-----
> From: netdev-owner@xxxxxxxxxxxxxxx [mailto:netdev-owner@xxxxxxxxxxxxxxx]
> On Behalf Of Lin Yun Sheng
> Sent: Tuesday, June 27, 2017 2:01 PM
> To: davem@xxxxxxxxxxxxx; andrew@xxxxxxx; f.fainelli@xxxxxxxxx
> Cc: huangdaode@xxxxxxxxxxxxx; xuwei5@xxxxxxxxxxxxx;
> liguozhu@xxxxxxxxxxxxx; Yisen.Zhuang@xxxxxxxxxx;
> gabriele.paoloni@xxxxxxxxxx; john.garry@xxxxxxxxxx; linuxarm@xxxxxxxxxx;
> yisen.zhuang@xxxxxxxxxx; salil.mehta@xxxxxxxxxx; lipeng321@xxxxxxxxxx;
> tremyfr@xxxxxxxxx; netdev@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: [PATCH NET V6 1/2] net: phy: Add phy loopback support in net phy
> framework
> 
> This patch add set_loopback in phy_driver, which is used by Mac
> driver to enable or disable a phy. it also add a generic
> genphy_loopback function, which use BMCR loopback bit to enable
> or disable a phy.

"disable a phy" or disable the PHY loopback function?

> 
> Signed-off-by: Lin Yun Sheng <linyunsheng@xxxxxxxxxx>
> ---
>  drivers/net/phy/marvell.c    |  1 +
>  drivers/net/phy/phy_device.c | 51
> ++++++++++++++++++++++++++++++++++++++++++++
>  include/linux/phy.h          |  5 +++++
>  3 files changed, 57 insertions(+)
> 
> diff --git a/drivers/net/phy/marvell.c b/drivers/net/phy/marvell.c
> index 57297ba..01a1586 100644
> --- a/drivers/net/phy/marvell.c
> +++ b/drivers/net/phy/marvell.c
> @@ -2094,6 +2094,7 @@ static int m88e1510_probe(struct phy_device *phydev)
>  		.get_sset_count = marvell_get_sset_count,
>  		.get_strings = marvell_get_strings,
>  		.get_stats = marvell_get_stats,
> +		.set_loopback = genphy_loopback,
>  	},
>  	{
>  		.phy_id = MARVELL_PHY_ID_88E1540,
> diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
> index 1219eea..1e08d62 100644
> --- a/drivers/net/phy/phy_device.c
> +++ b/drivers/net/phy/phy_device.c
> @@ -1123,6 +1123,39 @@ int phy_resume(struct phy_device *phydev)
>  }
>  EXPORT_SYMBOL(phy_resume);
> 
> +int phy_loopback(struct phy_device *phydev, bool enable)
> +{
> +	struct phy_driver *phydrv = to_phy_driver(phydev->mdio.dev.driver);
> +	int ret = 0;
> +
> +	mutex_lock(&phydev->lock);
> +
> +	if (enable && phydev->loopback_enabled) {
> +		ret = -EBUSY;
> +		goto out;
> +	}
> +
> +	if (!enable && !phydev->loopback_enabled) {
> +		ret = -EINVAL;
> +		goto out;
> +	}
> +

if (enable == phydev->loopback_enabled)

> +	if (phydev->drv && phydrv->set_loopback)
> +		ret = phydrv->set_loopback(phydev, enable);
> +	else
> +		ret = -EOPNOTSUPP;
> +
> +	if (ret)
> +		goto out;
> +
> +	phydev->loopback_enabled = enable;
> +
> +out:
> +	mutex_unlock(&phydev->lock);
> +	return ret;
> +}
> +EXPORT_SYMBOL(phy_loopback);
> +
>  /* Generic PHY support and helper functions */
> 
>  /**
> @@ -1628,6 +1661,23 @@ static int gen10g_resume(struct phy_device *phydev)
>  	return 0;
>  }
> 
> +int genphy_loopback(struct phy_device *phydev, bool enable)
> +{
> +	int value;
> +
> +	value = phy_read(phydev, MII_BMCR);
> +	if (value < 0)
> +		return value;
> +
> +	if (enable)
> +		value |= BMCR_LOOPBACK;
> +	else
> +		value &= ~BMCR_LOOPBACK;
> +
> +	return phy_write(phydev, MII_BMCR, value);
> +}
> +EXPORT_SYMBOL(genphy_loopback);
> +
>  static int __set_phy_supported(struct phy_device *phydev, u32 max_speed)
>  {
>  	/* The default values for phydev->supported are provided by the PHY
> @@ -1874,6 +1924,7 @@ void phy_drivers_unregister(struct phy_driver *drv,
> int n)
>  	.read_status	= genphy_read_status,
>  	.suspend	= genphy_suspend,
>  	.resume		= genphy_resume,
> +	.set_loopback	= genphy_loopback,
>  }, {
>  	.phy_id         = 0xffffffff,
>  	.phy_id_mask    = 0xffffffff,
> diff --git a/include/linux/phy.h b/include/linux/phy.h
> index e76e4ad..49c903dc 100644
> --- a/include/linux/phy.h
> +++ b/include/linux/phy.h
> @@ -364,6 +364,7 @@ struct phy_c45_device_ids {
>   * is_pseudo_fixed_link: Set to true if this phy is an Ethernet switch,
> etc.
>   * has_fixups: Set to true if this phy has fixups/quirks.
>   * suspended: Set to true if this phy has been suspended successfully.
> + * loopback_enabled: Set true if this phy has been loopbacked
> successfully.
>   * state: state of the PHY for management purposes
>   * dev_flags: Device-specific flags used by the PHY driver.
>   * link_timeout: The number of timer firings to wait before the
> @@ -400,6 +401,7 @@ struct phy_device {
>  	bool is_pseudo_fixed_link;
>  	bool has_fixups;
>  	bool suspended;
> +	bool loopback_enabled;
> 
>  	enum phy_state state;
> 
> @@ -639,6 +641,7 @@ struct phy_driver {
>  	int (*set_tunable)(struct phy_device *dev,
>  			    struct ethtool_tunable *tuna,
>  			    const void *data);
> +	int (*set_loopback)(struct phy_device *dev, bool enable);
>  };
>  #define to_phy_driver(d) container_of(to_mdio_common_driver(d),		\
>  				      struct phy_driver, mdiodrv)
> @@ -774,6 +777,7 @@ static inline void phy_device_free(struct phy_device
> *phydev) { }
>  int phy_init_hw(struct phy_device *phydev);
>  int phy_suspend(struct phy_device *phydev);
>  int phy_resume(struct phy_device *phydev);
> +int phy_loopback(struct phy_device *phydev, bool enable);
>  struct phy_device *phy_attach(struct net_device *dev, const char *bus_id,
>  			      phy_interface_t interface);
>  struct phy_device *phy_find_first(struct mii_bus *bus);
> @@ -825,6 +829,7 @@ void phy_attached_print(struct phy_device *phydev,
> const char *fmt, ...)
>  int genphy_read_status(struct phy_device *phydev);
>  int genphy_suspend(struct phy_device *phydev);
>  int genphy_resume(struct phy_device *phydev);
> +int genphy_loopback(struct phy_device *phydev, bool enable);
>  int genphy_soft_reset(struct phy_device *phydev);
>  static inline int genphy_no_soft_reset(struct phy_device *phydev)
>  {
> --
> 1.9.1

Madalin