RE: [PATCH] wifi: rtw88: Add USB PHY configuration

[Ping-Ke Shih <pkshih@realtek.com>]

Bitterblue Smith <rtl8821cerfe2@gmail.com> wrote:
> Add some extra configuration for USB devices. Currently only RTL8822BU
> version (cut) D needs this. The new code makes use of the existing
> usb3_param_8822b array from rtw8822b.c.
> 
> A user reported that TP-Link Archer T3U in USB 3 mode was randomly
> disconnecting from USB:
> 
> [ 26.036502] usb 2-2: new SuperSpeed USB device number 3 using xhci_hcd
> ...
> [ 27.576491] usb 2-2: USB disconnect, device number 3
> [ 28.621528] usb 2-2: new SuperSpeed USB device number 4 using xhci_hcd
> ...
> [ 45.984521] usb 2-2: USB disconnect, device number 4
> ...
> [ 46.845585] usb 2-2: new SuperSpeed USB device number 5 using xhci_hcd
> ...
> [ 94.400380] usb 2-2: USB disconnect, device number 5
> ...
> [ 95.590421] usb 2-2: new SuperSpeed USB device number 6 using xhci_hcd
> 
> This patch fixes that.
> 
> Link: https://github.com/lwfinger/rtw88/issues/262.

As Kalle mentioned, please remove the dot in the end. 

By the way, I can modify commit message during committing if needed. 

> Signed-off-by: Bitterblue Smith <rtl8821cerfe2@gmail.com>
> ---
>  drivers/net/wireless/realtek/rtw88/usb.c | 70 ++++++++++++++++++++++++
>  1 file changed, 70 insertions(+)
> 
> diff --git a/drivers/net/wireless/realtek/rtw88/usb.c b/drivers/net/wireless/realtek/rtw88/usb.c
> index b405f8317021..b5ef7e31df19 100644
> --- a/drivers/net/wireless/realtek/rtw88/usb.c
> +++ b/drivers/net/wireless/realtek/rtw88/usb.c
> @@ -1127,6 +1127,73 @@ static int rtw_usb_switch_mode(struct rtw_dev *rtwdev)
>                 return rtw_usb_switch_mode_new(rtwdev);
>  }
> 
> +#define USB_REG_PAGE   0xf4
> +#define USB_PHY_PAGE0  0x9b
> +#define USB_PHY_PAGE1  0xbb
> +
> +static void rtw_usb_phy_write(struct rtw_dev *rtwdev, u16 addr, u16 data,
> +                             enum usb_device_speed speed)
> +{
> +       if (speed == USB_SPEED_SUPER) {
> +               rtw_write8(rtwdev, 0xff0d, (u8)data);
> +               rtw_write8(rtwdev, 0xff0e, (u8)(data >> 8));
> +               rtw_write8(rtwdev, 0xff0c, addr | BIT(7));

The casting of u8 is not unnecessary.

The register names (non-official naming):

#define U3_PHY_DAT_L 0xff0d
#define U3_PHY_DAT_H 0xff0e
#define U3_PHY_ADR 0xff0c
#define U3_PHY_ADR_WR BIT(7)
#define U3_PHY_ADR_RD BIT(6)
#define U3_PHY_ADR_MASK GENMASK(5, 0)


> +       } else if (speed == USB_SPEED_HIGH) {
> +               rtw_write8(rtwdev, 0xfe41, (u8)data);
> +               rtw_write8(rtwdev, 0xfe40, addr);
> +               rtw_write8(rtwdev, 0xfe42, 0x81);

The register names (non-official naming):

#define U2_PHY_DAT 0xfe41
#define U2_PHY_ADR 0xfe40
#define U2_PHY_CMD 0xfe42
#define U2_PHY_CMD_TRG 0x81

> +       }
> +}
> +
> +static void rtw_usb_page_switch(struct rtw_dev *rtwdev,
> +                               enum usb_device_speed speed, u8 page)
> +{
> +       if (speed == USB_SPEED_SUPER)
> +               return;
> +
> +       rtw_usb_phy_write(rtwdev, USB_REG_PAGE, page, speed);
> +}
> +
> +static void rtw_usb_phy_cfg(struct rtw_dev *rtwdev,
> +                           enum usb_device_speed speed)
> +{
> +       const struct rtw_intf_phy_para *para = NULL;
> +       u16 cut, offset;
> +
> +       if (!rtwdev->chip->intf_table)
> +               return;
> +
> +       if (speed == USB_SPEED_SUPER)
> +               para = rtwdev->chip->intf_table->usb3_para;
> +       else if (speed == USB_SPEED_HIGH)
> +               para = rtwdev->chip->intf_table->usb2_para;
> +
> +       if (!para)
> +               return;
> +
> +       cut = BIT(0) << rtwdev->hal.cut_version;

cut = BIT(rtwdev->hal.cut_version);

> +
> +       for ( ; para->offset != 0xffff; para++) {
> +               if (!(para->cut_mask & cut))
> +                       continue;
> +
> +               offset = para->offset;
> +
> +               if (para->ip_sel == RTW_IP_SEL_MAC) {
> +                       rtw_write8(rtwdev, offset, para->value);
> +               } else {
> +                       if (offset > 0x100)
> +                               rtw_usb_page_switch(rtwdev, speed, USB_PHY_PAGE1);
> +                       else
> +                               rtw_usb_page_switch(rtwdev, speed, USB_PHY_PAGE0);
> +
> +                       offset &= 0xff;
> +
> +                       rtw_usb_phy_write(rtwdev, offset, para->value, speed);

The argument type of offset can be 'u8', so you don't worry about type casting.

> +               }
> +       }
> +}
> +
>  int rtw_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
>  {
>         struct rtw_dev *rtwdev;
> @@ -1182,6 +1249,9 @@ int rtw_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
>                 goto err_destroy_rxwq;
>         }
> 
> +       rtw_usb_phy_cfg(rtwdev, USB_SPEED_HIGH);
> +       rtw_usb_phy_cfg(rtwdev, USB_SPEED_SUPER);
> +
>         ret = rtw_usb_switch_mode(rtwdev);
>         if (ret) {
>                 /* Not a fail, but we do need to skip rtw_register_hw. */
> --
> 2.47.1