[PATCH 2/5] net: phy: Add phy_modify_mmd() and phy_modify_mmd_changed() from Linux

[Ramon Fried]

On Sun, Mar 19, 2023 at 7:08 PM Marek Vasut
<marek.vasut+renesas at mailbox.org> wrote:
>
> Add phy_modify_mmd()/phy_modify_mmd_changed() from Linux 5.1.y as of commit
> b8554d4f7288f ("net: phy: add register modifying helpers returning 1 on change")
> This is used by the upcoming Marvell 10G PHY driver.
>
> Signed-off-by: Marek Vasut <marek.vasut+renesas at mailbox.org>
> ---
> Cc: "Ariel D'Alessandro" <ariel.dalessandro at collabora.com>
> Cc: "Marek Behún" <kabel at kernel.org>
> Cc: Joe Hershberger <joe.hershberger at ni.com>
> Cc: Marek Vasut <marek.vasut+renesas at mailbox.org>
> Cc: Michael Trimarchi <michael at amarulasolutions.com>
> Cc: Nate Drude <nate.d at variscite.com>
> Cc: Ramon Fried <rfried.dev at gmail.com>
> Cc: Simon Glass <sjg at chromium.org>
> Cc: Stefan Roese <sr at denx.de>
> Cc: Tim Harvey <tharvey at gateworks.com>
> Cc: Vladimir Oltean <vladimir.oltean at nxp.com>
> ---
>  drivers/net/phy/phy.c | 54 +++++++++++++++++++++++++++++++++++++++++++
>  include/phy.h         |  4 ++++
>  2 files changed, 58 insertions(+)
>
> diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
> index f720d0a7920..0eeb0cb3a85 100644
> --- a/drivers/net/phy/phy.c
> +++ b/drivers/net/phy/phy.c
> @@ -1158,6 +1158,60 @@ int phy_clear_bits_mmd(struct phy_device *phydev, int devad, u32 regnum, u16 val
>         return 0;
>  }
>
> +/**
> + * phy_modify_mmd_changed - Function for modifying a register on MMD
> + * @phydev: the phy_device struct
> + * @devad: the MMD containing register to modify
> + * @regnum: register number to modify
> + * @mask: bit mask of bits to clear
> + * @set: new value of bits set in mask to write to @regnum
> + *
> + * NOTE: MUST NOT be called from interrupt context,
> + * because the bus read/write functions may wait for an interrupt
> + * to conclude the operation.
> + *
> + * Returns negative errno, 0 if there was no change, and 1 in case of change
> + */
> +int phy_modify_mmd_changed(struct phy_device *phydev, int devad, u32 regnum,
> +                          u16 mask, u16 set)
> +{
> +       int new, ret;
> +
> +       ret = phy_read_mmd(phydev, devad, regnum);
> +       if (ret < 0)
> +               return ret;
> +
> +       new = (ret & ~mask) | set;
> +       if (new == ret)
> +               return 0;
> +
> +       ret = phy_write_mmd(phydev, devad, regnum, new);
> +
> +       return ret < 0 ? ret : 1;
> +}
> +
> +/**
> + * phy_modify_mmd - Convenience function for modifying a register on MMD
> + * @phydev: the phy_device struct
> + * @devad: the MMD containing register to modify
> + * @regnum: register number to modify
> + * @mask: bit mask of bits to clear
> + * @set: new value of bits set in mask to write to @regnum
> + *
> + * NOTE: MUST NOT be called from interrupt context,
> + * because the bus read/write functions may wait for an interrupt
> + * to conclude the operation.
> + */
> +int phy_modify_mmd(struct phy_device *phydev, int devad, u32 regnum,
> +                  u16 mask, u16 set)
> +{
> +       int ret;
> +
> +       ret = phy_modify_mmd_changed(phydev, devad, regnum, mask, set);
> +
> +       return ret < 0 ? ret : 0;
> +}
> +
>  bool phy_interface_is_ncsi(void)
>  {
>  #ifdef CONFIG_PHY_NCSI
> diff --git a/include/phy.h b/include/phy.h
> index 4a9de461152..34675b2c9c0 100644
> --- a/include/phy.h
> +++ b/include/phy.h
> @@ -289,6 +289,10 @@ int phy_read_mmd(struct phy_device *phydev, int devad, int regnum);
>  int phy_write_mmd(struct phy_device *phydev, int devad, int regnum, u16 val);
>  int phy_set_bits_mmd(struct phy_device *phydev, int devad, u32 regnum, u16 val);
>  int phy_clear_bits_mmd(struct phy_device *phydev, int devad, u32 regnum, u16 val);
> +int phy_modify_mmd_changed(struct phy_device *phydev, int devad, u32 regnum,
> +                          u16 mask, u16 set);
> +int phy_modify_mmd(struct phy_device *phydev, int devad, u32 regnum,
> +                  u16 mask, u16 set);
>
>  int phy_startup(struct phy_device *phydev);
>  int phy_config(struct phy_device *phydev);
> --
> 2.39.2
>
Reviewed-by: Ramon Fried <rfried.dev at gmail.com>