Message-ID: <CA+V-a8tBPHA00n9MyP_PJa8KzTMDNJBoE7n+DzuzT_ObR7SuJw@mail.gmail.com>
Date: Tue, 25 Feb 2025 20:44:25 +0000
From: "Lad, Prabhakar" <prabhakar.csengg@...il.com>
To: Claudiu <claudiu.beznea@...on.dev>
Cc: yoshihiro.shimoda.uh@...esas.com, vkoul@...nel.org, kishon@...nel.org, 
	horms+renesas@...ge.net.au, fabrizio.castro.jz@...esas.com, 
	linux-renesas-soc@...r.kernel.org, linux-phy@...ts.infradead.org, 
	linux-kernel@...r.kernel.org, 
	Claudiu Beznea <claudiu.beznea.uj@...renesas.com>, stable@...r.kernel.org
Subject: Re: [PATCH v2 1/5] phy: renesas: rcar-gen3-usb2: Fix role detection
 on unbind/bind

On Tue, Feb 25, 2025 at 10:59 AM Claudiu <claudiu.beznea@...on.dev> wrote:
>
> From: Claudiu Beznea <claudiu.beznea.uj@...renesas.com>
>
> It has been observed on the Renesas RZ/G3S SoC that unbinding and binding
> the PHY driver leads to role autodetection failures. This issue occurs when
> PHY 3 is the first initialized PHY. PHY 3 does not have an interrupt
> associated with the USB2_INT_ENABLE register (as
> rcar_gen3_int_enable[3] = 0). As a result, rcar_gen3_init_otg() is called
> to initialize OTG without enabling PHY interrupts.
>
> To resolve this, add rcar_gen3_is_any_otg_rphy_initialized() and call it in
> role_store(), role_show(), and rcar_gen3_init_otg(). At the same time,
> rcar_gen3_init_otg() is only called when initialization for a PHY with
> interrupt bits is in progress. As a result, the
> struct rcar_gen3_phy::otg_initialized is no longer needed.
>
> Fixes: 549b6b55b005 ("phy: renesas: rcar-gen3-usb2: enable/disable independent irqs")
> Cc: stable@...r.kernel.org
> Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@...esas.com>
> Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@...esas.com>
> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@...renesas.com>
> ---
>
> Changes in v2:
> - collected tags
>
>  drivers/phy/renesas/phy-rcar-gen3-usb2.c | 33 ++++++++++--------------
>  1 file changed, 14 insertions(+), 19 deletions(-)
>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>

Cheers,
Prabhakar

> diff --git a/drivers/phy/renesas/phy-rcar-gen3-usb2.c b/drivers/phy/renesas/phy-rcar-gen3-usb2.c
> index 775f4f973a6c..46afba2fe0dc 100644
> --- a/drivers/phy/renesas/phy-rcar-gen3-usb2.c
> +++ b/drivers/phy/renesas/phy-rcar-gen3-usb2.c
> @@ -107,7 +107,6 @@ struct rcar_gen3_phy {
>         struct rcar_gen3_chan *ch;
>         u32 int_enable_bits;
>         bool initialized;
> -       bool otg_initialized;
>         bool powered;
>  };
>
> @@ -320,16 +319,15 @@ static bool rcar_gen3_is_any_rphy_initialized(struct rcar_gen3_chan *ch)
>         return false;
>  }
>
> -static bool rcar_gen3_needs_init_otg(struct rcar_gen3_chan *ch)
> +static bool rcar_gen3_is_any_otg_rphy_initialized(struct rcar_gen3_chan *ch)
>  {
> -       int i;
> -
> -       for (i = 0; i < NUM_OF_PHYS; i++) {
> -               if (ch->rphys[i].otg_initialized)
> -                       return false;
> +       for (enum rcar_gen3_phy_index i = PHY_INDEX_BOTH_HC; i <= PHY_INDEX_EHCI;
> +            i++) {
> +               if (ch->rphys[i].initialized)
> +                       return true;
>         }
>
> -       return true;
> +       return false;
>  }
>
>  static bool rcar_gen3_are_all_rphys_power_off(struct rcar_gen3_chan *ch)
> @@ -351,7 +349,7 @@ static ssize_t role_store(struct device *dev, struct device_attribute *attr,
>         bool is_b_device;
>         enum phy_mode cur_mode, new_mode;
>
> -       if (!ch->is_otg_channel || !rcar_gen3_is_any_rphy_initialized(ch))
> +       if (!ch->is_otg_channel || !rcar_gen3_is_any_otg_rphy_initialized(ch))
>                 return -EIO;
>
>         if (sysfs_streq(buf, "host"))
> @@ -389,7 +387,7 @@ static ssize_t role_show(struct device *dev, struct device_attribute *attr,
>  {
>         struct rcar_gen3_chan *ch = dev_get_drvdata(dev);
>
> -       if (!ch->is_otg_channel || !rcar_gen3_is_any_rphy_initialized(ch))
> +       if (!ch->is_otg_channel || !rcar_gen3_is_any_otg_rphy_initialized(ch))
>                 return -EIO;
>
>         return sprintf(buf, "%s\n", rcar_gen3_is_host(ch) ? "host" :
> @@ -402,6 +400,9 @@ static void rcar_gen3_init_otg(struct rcar_gen3_chan *ch)
>         void __iomem *usb2_base = ch->base;
>         u32 val;
>
> +       if (!ch->is_otg_channel || rcar_gen3_is_any_otg_rphy_initialized(ch))
> +               return;
> +
>         /* Should not use functions of read-modify-write a register */
>         val = readl(usb2_base + USB2_LINECTRL1);
>         val = (val & ~USB2_LINECTRL1_DP_RPD) | USB2_LINECTRL1_DPRPD_EN |
> @@ -465,12 +466,9 @@ static int rcar_gen3_phy_usb2_init(struct phy *p)
>         writel(USB2_SPD_RSM_TIMSET_INIT, usb2_base + USB2_SPD_RSM_TIMSET);
>         writel(USB2_OC_TIMSET_INIT, usb2_base + USB2_OC_TIMSET);
>
> -       /* Initialize otg part */
> -       if (channel->is_otg_channel) {
> -               if (rcar_gen3_needs_init_otg(channel))
> -                       rcar_gen3_init_otg(channel);
> -               rphy->otg_initialized = true;
> -       }
> +       /* Initialize otg part (only if we initialize a PHY with IRQs). */
> +       if (rphy->int_enable_bits)
> +               rcar_gen3_init_otg(channel);
>
>         rphy->initialized = true;
>
> @@ -486,9 +484,6 @@ static int rcar_gen3_phy_usb2_exit(struct phy *p)
>
>         rphy->initialized = false;
>
> -       if (channel->is_otg_channel)
> -               rphy->otg_initialized = false;
> -
>         val = readl(usb2_base + USB2_INT_ENABLE);
>         val &= ~rphy->int_enable_bits;
>         if (!rcar_gen3_is_any_rphy_initialized(channel))
> --
> 2.43.0
>
>

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