[PATCH] wifi: rtw88: usb: Support USB 3 with RTL8822CU/RTL8822BU

[PATCH] wifi: rtw88: usb: Support USB 3 with RTL8822CU/RTL8822BU

[Bitterblue Smith]

The Realtek wifi 5 devices which support USB 3 are weird: when first
plugged in, they pretend to be USB 2. The driver needs to send some
commands to the device, which make it disappear and come back as a
USB 3 device.

Implement the required commands in rtw88.

When a USB 3 device is plugged into a USB 2 port, rtw88 will try to
switch it to USB 3 mode only once. The device will disappear and come
back still in USB 2 mode, of course.

Some people experience heavy interference in the 2.4 GHz band in
USB 3 mode, so add a module parameter switch_usb_mode with the
default value 1 to let people disable the switching.

Signed-off-by: Bitterblue Smith <rtl8821cerfe2@gmail.com>
---
A later patch will add the function rtw_usb_switch_mode_old() for the
older chips RTL8812AU and RTL8814AU.
---
 drivers/net/wireless/realtek/rtw88/main.h     |  2 +
 drivers/net/wireless/realtek/rtw88/reg.h      | 11 +++
 drivers/net/wireless/realtek/rtw88/rtw8822b.c |  1 +
 drivers/net/wireless/realtek/rtw88/rtw8822b.h |  4 +-
 drivers/net/wireless/realtek/rtw88/rtw8822c.c |  1 +
 drivers/net/wireless/realtek/rtw88/rtw8822c.h | 24 +++---
 drivers/net/wireless/realtek/rtw88/usb.c      | 84 +++++++++++++++++++
 7 files changed, 115 insertions(+), 12 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtw88/main.h b/drivers/net/wireless/realtek/rtw88/main.h
index 49a3fd4fb7dc..9d21637cf5d5 100644
--- a/drivers/net/wireless/realtek/rtw88/main.h
+++ b/drivers/net/wireless/realtek/rtw88/main.h
@@ -1785,6 +1785,8 @@ struct rtw_efuse {
 	bool share_ant;
 	u8 bt_setting;
 
+	u8 usb_mode_switch;
+
 	struct {
 		u8 hci;
 		u8 bw;
diff --git a/drivers/net/wireless/realtek/rtw88/reg.h b/drivers/net/wireless/realtek/rtw88/reg.h
index 02ef9a77316b..e7b24465f549 100644
--- a/drivers/net/wireless/realtek/rtw88/reg.h
+++ b/drivers/net/wireless/realtek/rtw88/reg.h
@@ -15,6 +15,7 @@
 #define BIT_WLOCK_1C_B6		BIT(5)
 #define REG_SYS_PW_CTRL		0x0004
 #define BIT_PFM_WOWL		BIT(3)
+#define BIT_APFM_OFFMAC		BIT(9)
 #define REG_SYS_CLK_CTRL	0x0008
 #define BIT_CPU_CLK_EN		BIT(14)
 
@@ -133,6 +134,14 @@
 #define REG_PMC_DBG_CTRL1	0xa8
 #define BITS_PMC_BT_IQK_STS	GENMASK(22, 21)
 
+#define REG_PAD_CTRL2		0x00C4
+#define BIT_RSM_EN_V1		BIT(16)
+#define BIT_NO_PDN_CHIPOFF_V1	BIT(17)
+#define BIT_MASK_USB23_SW_MODE_V1	GENMASK(19, 18)
+#define BIT_USB3_USB2_TRANSITION	BIT(20)
+#define BIT_USB_MODE_U2		1
+#define BIT_USB_MODE_U3		2
+
 #define REG_EFUSE_ACCESS	0x00CF
 #define EFUSE_ACCESS_ON		0x69
 #define EFUSE_ACCESS_OFF	0x00
@@ -568,6 +577,8 @@
 #define BIT_WL_SECURITY_CLK	BIT(15)
 #define BIT_DDMA_EN		BIT(8)
 
+#define REG_SW_MDIO		0x10C0
+
 #define REG_H2C_PKT_READADDR	0x10D0
 #define REG_H2C_PKT_WRITEADDR	0x10D4
 #define REG_FW_DBG6		0x10F8
diff --git a/drivers/net/wireless/realtek/rtw88/rtw8822b.c b/drivers/net/wireless/realtek/rtw88/rtw8822b.c
index 2456ff242818..6edb17aea90e 100644
--- a/drivers/net/wireless/realtek/rtw88/rtw8822b.c
+++ b/drivers/net/wireless/realtek/rtw88/rtw8822b.c
@@ -46,6 +46,7 @@ static int rtw8822b_read_efuse(struct rtw_dev *rtwdev, u8 *log_map)
 
 	map = (struct rtw8822b_efuse *)log_map;
 
+	efuse->usb_mode_switch = u8_get_bits(map->usb_mode, BIT(7));
 	efuse->rfe_option = map->rfe_option;
 	efuse->rf_board_option = map->rf_board_option;
 	efuse->crystal_cap = map->xtal_k;
diff --git a/drivers/net/wireless/realtek/rtw88/rtw8822b.h b/drivers/net/wireless/realtek/rtw88/rtw8822b.h
index 2dc3a6660f06..cf85e63966a1 100644
--- a/drivers/net/wireless/realtek/rtw88/rtw8822b.h
+++ b/drivers/net/wireless/realtek/rtw88/rtw8822b.h
@@ -72,7 +72,9 @@ struct rtw8822bs_efuse {
 
 struct rtw8822b_efuse {
 	__le16 rtl_id;
-	u8 res0[0x0e];
+	u8 res0[4];
+	u8 usb_mode;
+	u8 res1[0x09];
 
 	/* power index for four RF paths */
 	struct rtw_txpwr_idx txpwr_idx_table[4];
diff --git a/drivers/net/wireless/realtek/rtw88/rtw8822c.c b/drivers/net/wireless/realtek/rtw88/rtw8822c.c
index 62376d1cca22..bc807b13e9ce 100644
--- a/drivers/net/wireless/realtek/rtw88/rtw8822c.c
+++ b/drivers/net/wireless/realtek/rtw88/rtw8822c.c
@@ -49,6 +49,7 @@ static int rtw8822c_read_efuse(struct rtw_dev *rtwdev, u8 *log_map)
 
 	map = (struct rtw8822c_efuse *)log_map;
 
+	efuse->usb_mode_switch = u8_get_bits(map->usb_mode, BIT(7));
 	efuse->rfe_option = map->rfe_option;
 	efuse->rf_board_option = map->rf_board_option;
 	efuse->crystal_cap = map->xtal_k & XCAP_MASK;
diff --git a/drivers/net/wireless/realtek/rtw88/rtw8822c.h b/drivers/net/wireless/realtek/rtw88/rtw8822c.h
index 1bc0e7f5d6bb..e2b383d633cd 100644
--- a/drivers/net/wireless/realtek/rtw88/rtw8822c.h
+++ b/drivers/net/wireless/realtek/rtw88/rtw8822c.h
@@ -59,16 +59,18 @@ struct rtw8822ce_efuse {
 
 struct rtw8822c_efuse {
 	__le16 rtl_id;
-	u8 res0[0x0e];
+	u8 res0[4];
+	u8 usb_mode;
+	u8 res1[0x09];
 
 	/* power index for four RF paths */
 	struct rtw_txpwr_idx txpwr_idx_table[4];
 
 	u8 channel_plan;		/* 0xb8 */
 	u8 xtal_k;
-	u8 res1;
+	u8 res2;
 	u8 iqk_lck;
-	u8 res2[5];			/* 0xbc */
+	u8 res3[5];			/* 0xbc */
 	u8 rf_board_option;
 	u8 rf_feature_option;
 	u8 rf_bt_setting;
@@ -80,21 +82,21 @@ struct rtw8822c_efuse {
 	u8 rf_antenna_option;		/* 0xc9 */
 	u8 rfe_option;
 	u8 country_code[2];
-	u8 res3[3];
+	u8 res4[3];
 	u8 path_a_thermal;		/* 0xd0 */
 	u8 path_b_thermal;
-	u8 res4[2];
+	u8 res5[2];
 	u8 rx_gain_gap_2g_ofdm;
-	u8 res5;
-	u8 rx_gain_gap_2g_cck;
 	u8 res6;
-	u8 rx_gain_gap_5gl;
+	u8 rx_gain_gap_2g_cck;
 	u8 res7;
-	u8 rx_gain_gap_5gm;
+	u8 rx_gain_gap_5gl;
 	u8 res8;
-	u8 rx_gain_gap_5gh;
+	u8 rx_gain_gap_5gm;
 	u8 res9;
-	u8 res10[0x42];
+	u8 rx_gain_gap_5gh;
+	u8 res10;
+	u8 res11[0x42];
 	union {
 		struct rtw8822ce_efuse e;
 		struct rtw8822cu_efuse u;
diff --git a/drivers/net/wireless/realtek/rtw88/usb.c b/drivers/net/wireless/realtek/rtw88/usb.c
index a55ca5a24227..a59e52a0da10 100644
--- a/drivers/net/wireless/realtek/rtw88/usb.c
+++ b/drivers/net/wireless/realtek/rtw88/usb.c
@@ -14,6 +14,11 @@
 #include "ps.h"
 #include "usb.h"
 
+static bool rtw_switch_usb_mode = true;
+module_param_named(switch_usb_mode, rtw_switch_usb_mode, bool, 0644);
+MODULE_PARM_DESC(switch_usb_mode,
+		 "Set to Y to switch to USB 3 mode (default: Y)");
+
 #define RTW_USB_MAX_RXQ_LEN	512
 
 struct rtw_usb_txcb {
@@ -841,6 +846,77 @@ static void rtw_usb_intf_deinit(struct rtw_dev *rtwdev,
 	usb_set_intfdata(intf, NULL);
 }
 
+static int rtw_usb_switch_mode_new(struct rtw_dev *rtwdev)
+{
+	enum usb_device_speed cur_speed;
+	u8 id = rtwdev->chip->id;
+	bool can_switch;
+	u32 pad_ctrl2;
+
+	if (rtw_read8(rtwdev, REG_SYS_CFG2 + 3) == 0x20)
+		cur_speed = USB_SPEED_SUPER;
+	else
+		cur_speed = USB_SPEED_HIGH;
+
+	if (cur_speed == USB_SPEED_SUPER)
+		return 0;
+
+	pad_ctrl2 = rtw_read32(rtwdev, REG_PAD_CTRL2);
+
+	can_switch = !!(pad_ctrl2 & (BIT_MASK_USB23_SW_MODE_V1 |
+				     BIT_USB3_USB2_TRANSITION));
+
+	if (!can_switch) {
+		rtw_info(rtwdev,
+			 "Switching to USB 3 mode unsupported by the chip\n");
+		return 0;
+	}
+
+	/* At this point cur_speed is USB_SPEED_HIGH. If we already tried
+	 * to switch don't try again - it's a USB 2 port.
+	 */
+	if ((u32_get_bits(pad_ctrl2, BIT_MASK_USB23_SW_MODE_V1) == BIT_USB_MODE_U3))
+		return 0;
+
+	/* Enable IO wrapper timeout */
+	if (id == RTW_CHIP_TYPE_8822B || id == RTW_CHIP_TYPE_8821C)
+		rtw_write8_clr(rtwdev, REG_SW_MDIO + 3, BIT(0));
+
+	u32p_replace_bits(&pad_ctrl2, BIT_USB_MODE_U3, BIT_MASK_USB23_SW_MODE_V1);
+	pad_ctrl2 |= BIT_RSM_EN_V1;
+
+	rtw_write32(rtwdev, REG_PAD_CTRL2, pad_ctrl2);
+	rtw_write8(rtwdev, REG_PAD_CTRL2 + 1, 4);
+
+	rtw_write16_set(rtwdev, REG_SYS_PW_CTRL, BIT_APFM_OFFMAC);
+	usleep_range(1000, 1001);
+	rtw_write32_set(rtwdev, REG_PAD_CTRL2, BIT_NO_PDN_CHIPOFF_V1);
+
+	return 1;
+}
+
+static int rtw_usb_switch_mode(struct rtw_dev *rtwdev)
+{
+	u8 id = rtwdev->chip->id;
+
+	if (id != RTW_CHIP_TYPE_8822C && id != RTW_CHIP_TYPE_8822B)
+		return 0;
+
+	if (!rtwdev->efuse.usb_mode_switch) {
+		rtw_info(rtwdev,
+			 "Switching to USB 3 mode disabled by chip's efuse\n");
+		return 0;
+	}
+
+	if (!rtw_switch_usb_mode) {
+		rtw_info(rtwdev,
+			 "Switching to USB 3 mode disabled by module parameter\n");
+		return 0;
+	}
+
+	return rtw_usb_switch_mode_new(rtwdev);
+}
+
 int rtw_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
 {
 	struct rtw_dev *rtwdev;
@@ -896,6 +972,14 @@ int rtw_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
 		goto err_destroy_rxwq;
 	}
 
+	ret = rtw_usb_switch_mode(rtwdev);
+	if (ret) {
+		/* Not a fail, but we do need to skip rtw_register_hw. */
+		rtw_info(rtwdev, "switching to USB 3 mode\n");
+		ret = 0;
+		goto err_destroy_rxwq;
+	}
+
 	ret = rtw_register_hw(rtwdev, rtwdev->hw);
 	if (ret) {
 		rtw_err(rtwdev, "failed to register hw\n");
-- 
2.45.1

RE: [PATCH] wifi: rtw88: usb: Support USB 3 with RTL8822CU/RTL8822BU

[Ping-Ke Shih]

Bitterblue Smith <rtl8821cerfe2@gmail.com> wrote:
> The Realtek wifi 5 devices which support USB 3 are weird: when first
> plugged in, they pretend to be USB 2. The driver needs to send some
> commands to the device, which make it disappear and come back as a
> USB 3 device.
> 
> Implement the required commands in rtw88.
> 
> When a USB 3 device is plugged into a USB 2 port, rtw88 will try to
> switch it to USB 3 mode only once. The device will disappear and come
> back still in USB 2 mode, of course.
> 
> Some people experience heavy interference in the 2.4 GHz band in
> USB 3 mode, so add a module parameter switch_usb_mode with the
> default value 1 to let people disable the switching.
> 
> Signed-off-by: Bitterblue Smith <rtl8821cerfe2@gmail.com>
> ---
> A later patch will add the function rtw_usb_switch_mode_old() for the
> older chips RTL8812AU and RTL8814AU.

[...]

> diff --git a/drivers/net/wireless/realtek/rtw88/usb.c b/drivers/net/wireless/realtek/rtw88/usb.c
> index a55ca5a24227..a59e52a0da10 100644
> --- a/drivers/net/wireless/realtek/rtw88/usb.c
> +++ b/drivers/net/wireless/realtek/rtw88/usb.c
> @@ -14,6 +14,11 @@
>  #include "ps.h"
>  #include "usb.h"
> 
> +static bool rtw_switch_usb_mode = true;
> +module_param_named(switch_usb_mode, rtw_switch_usb_mode, bool, 0644);
> +MODULE_PARM_DESC(switch_usb_mode,
> +                "Set to Y to switch to USB 3 mode (default: Y)");
> +

I feel we should say "Set to N to disable switching USB 3 mode to avoid
potential interference in the 2.4 GHz" like your commit message. That could
be helpful to users.

>  #define RTW_USB_MAX_RXQ_LEN    512
> 
>  struct rtw_usb_txcb {

[...]

> @@ -896,6 +972,14 @@ int rtw_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
>                 goto err_destroy_rxwq;
>         }
> 
> +       ret = rtw_usb_switch_mode(rtwdev);
> +       if (ret) {
> +               /* Not a fail, but we do need to skip rtw_register_hw. */
> +               rtw_info(rtwdev, "switching to USB 3 mode\n");

All logs in this patches should be rtw_dbg(), because these messages are not
important to users.


> +               ret = 0;
> +               goto err_destroy_rxwq;
> +       }
> +
>         ret = rtw_register_hw(rtwdev, rtwdev->hw);
>         if (ret) {
>                 rtw_err(rtwdev, "failed to register hw\n");
> --
> 2.45.1

Re: [PATCH] wifi: rtw88: usb: Support USB 3 with RTL8822CU/RTL8822BU

[Bitterblue Smith]

On 08/07/2024 12:19, Ping-Ke Shih wrote:
> Bitterblue Smith <rtl8821cerfe2@gmail.com> wrote:
>> The Realtek wifi 5 devices which support USB 3 are weird: when first
>> plugged in, they pretend to be USB 2. The driver needs to send some
>> commands to the device, which make it disappear and come back as a
>> USB 3 device.
>>
>> Implement the required commands in rtw88.
>>
>> When a USB 3 device is plugged into a USB 2 port, rtw88 will try to
>> switch it to USB 3 mode only once. The device will disappear and come
>> back still in USB 2 mode, of course.
>>
>> Some people experience heavy interference in the 2.4 GHz band in
>> USB 3 mode, so add a module parameter switch_usb_mode with the
>> default value 1 to let people disable the switching.
>>
>> Signed-off-by: Bitterblue Smith <rtl8821cerfe2@gmail.com>
>> ---
>> A later patch will add the function rtw_usb_switch_mode_old() for the
>> older chips RTL8812AU and RTL8814AU.
> 
> [...]
> 
>> diff --git a/drivers/net/wireless/realtek/rtw88/usb.c b/drivers/net/wireless/realtek/rtw88/usb.c
>> index a55ca5a24227..a59e52a0da10 100644
>> --- a/drivers/net/wireless/realtek/rtw88/usb.c
>> +++ b/drivers/net/wireless/realtek/rtw88/usb.c
>> @@ -14,6 +14,11 @@
>>  #include "ps.h"
>>  #include "usb.h"
>>
>> +static bool rtw_switch_usb_mode = true;
>> +module_param_named(switch_usb_mode, rtw_switch_usb_mode, bool, 0644);
>> +MODULE_PARM_DESC(switch_usb_mode,
>> +                "Set to Y to switch to USB 3 mode (default: Y)");
>> +
> 
> I feel we should say "Set to N to disable switching USB 3 mode to avoid
> potential interference in the 2.4 GHz" like your commit message. That could
> be helpful to users.
> 

Sounds good.

>>  #define RTW_USB_MAX_RXQ_LEN    512
>>
>>  struct rtw_usb_txcb {
> 
> [...]
> 
>> @@ -896,6 +972,14 @@ int rtw_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
>>                 goto err_destroy_rxwq;
>>         }
>>
>> +       ret = rtw_usb_switch_mode(rtwdev);
>> +       if (ret) {
>> +               /* Not a fail, but we do need to skip rtw_register_hw. */
>> +               rtw_info(rtwdev, "switching to USB 3 mode\n");
> 
> All logs in this patches should be rtw_dbg(), because these messages are not
> important to users.
> 

Okay, I will add RTW_DBG_USB to enum rtw_debug_mask.

> 
>> +               ret = 0;
>> +               goto err_destroy_rxwq;
>> +       }
>> +
>>         ret = rtw_register_hw(rtwdev, rtwdev->hw);
>>         if (ret) {
>>                 rtw_err(rtwdev, "failed to register hw\n");
>> --
>> 2.45.1
> 

RE: [PATCH] wifi: rtw88: usb: Support USB 3 with RTL8822CU/RTL8822BU

[Ping-Ke Shih]

Bitterblue Smith <rtl8821cerfe2@gmail.com> wrote:
> On 08/07/2024 12:19, Ping-Ke Shih wrote:
> > Bitterblue Smith <rtl8821cerfe2@gmail.com> wrote:
> >> @@ -896,6 +972,14 @@ int rtw_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
> >>                 goto err_destroy_rxwq;
> >>         }
> >>
> >> +       ret = rtw_usb_switch_mode(rtwdev);
> >> +       if (ret) {
> >> +               /* Not a fail, but we do need to skip rtw_register_hw. */
> >> +               rtw_info(rtwdev, "switching to USB 3 mode\n");
> >
> > All logs in this patches should be rtw_dbg(), because these messages are not
> > important to users.
> >
> 
> Okay, I will add RTW_DBG_USB to enum rtw_debug_mask.
> 
> >
> >> +               ret = 0;

I missed this point "ret = 0" that rtw_usb_disconnect() will be called when
USB disconnect. Can't we just return an error code? any negative effect?

My point is to avoid calling rtw_usb_disconnect() for the case of switching
USB 3, because all stuffs have been freed by following error handles. 

> >> +               goto err_destroy_rxwq;
> >> +       }
> >> +
> >>         ret = rtw_register_hw(rtwdev, rtwdev->hw);
> >>         if (ret) {
> >>                 rtw_err(rtwdev, "failed to register hw\n");
> >> --
> >> 2.45.1
> >

Re: [PATCH] wifi: rtw88: usb: Support USB 3 with RTL8822CU/RTL8822BU

[Bitterblue Smith]

On 09/07/2024 03:55, Ping-Ke Shih wrote:
> Bitterblue Smith <rtl8821cerfe2@gmail.com> wrote:
>> On 08/07/2024 12:19, Ping-Ke Shih wrote:
>>> Bitterblue Smith <rtl8821cerfe2@gmail.com> wrote:
>>>> @@ -896,6 +972,14 @@ int rtw_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
>>>>                 goto err_destroy_rxwq;
>>>>         }
>>>>
>>>> +       ret = rtw_usb_switch_mode(rtwdev);
>>>> +       if (ret) {
>>>> +               /* Not a fail, but we do need to skip rtw_register_hw. */
>>>> +               rtw_info(rtwdev, "switching to USB 3 mode\n");
>>>
>>> All logs in this patches should be rtw_dbg(), because these messages are not
>>> important to users.
>>>
>>
>> Okay, I will add RTW_DBG_USB to enum rtw_debug_mask.
>>
>>>
>>>> +               ret = 0;
> 
> I missed this point "ret = 0" that rtw_usb_disconnect() will be called when
> USB disconnect. Can't we just return an error code? any negative effect?
> 
> My point is to avoid calling rtw_usb_disconnect() for the case of switching
> USB 3, because all stuffs have been freed by following error handles. 
> 

If we return an error code instead of 0, it still switches
to USB 3, but we get an error message:

Jul 09 13:47:54 ideapad2 kernel: rtw_8812au 1-4:1.0: probe with driver rtw_8812au failed with error 1                                                                      

>>>> +               goto err_destroy_rxwq;
>>>> +       }
>>>> +
>>>>         ret = rtw_register_hw(rtwdev, rtwdev->hw);
>>>>         if (ret) {
>>>>                 rtw_err(rtwdev, "failed to register hw\n");
>>>> --
>>>> 2.45.1
>>>
> 

RE: [PATCH] wifi: rtw88: usb: Support USB 3 with RTL8822CU/RTL8822BU

[Ping-Ke Shih]

Bitterblue Smith <rtl8821cerfe2@gmail.com> wrote:
> On 09/07/2024 03:55, Ping-Ke Shih wrote:
> > Bitterblue Smith <rtl8821cerfe2@gmail.com> wrote:
> >> On 08/07/2024 12:19, Ping-Ke Shih wrote:
> >>> Bitterblue Smith <rtl8821cerfe2@gmail.com> wrote:
> >>>> @@ -896,6 +972,14 @@ int rtw_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
> >>>>                 goto err_destroy_rxwq;
> >>>>         }
> >>>>
> >>>> +       ret = rtw_usb_switch_mode(rtwdev);
> >>>> +       if (ret) {
> >>>> +               /* Not a fail, but we do need to skip rtw_register_hw. */
> >>>> +               rtw_info(rtwdev, "switching to USB 3 mode\n");
> >>>
> >>> All logs in this patches should be rtw_dbg(), because these messages are not
> >>> important to users.
> >>>
> >>
> >> Okay, I will add RTW_DBG_USB to enum rtw_debug_mask.
> >>
> >>>
> >>>> +               ret = 0;
> >
> > I missed this point "ret = 0" that rtw_usb_disconnect() will be called when
> > USB disconnect. Can't we just return an error code? any negative effect?
> >
> > My point is to avoid calling rtw_usb_disconnect() for the case of switching
> > USB 3, because all stuffs have been freed by following error handles.
> >
> 
> If we return an error code instead of 0, it still switches
> to USB 3, but we get an error message:
> 
> Jul 09 13:47:54 ideapad2 kernel: rtw_8812au 1-4:1.0: probe with driver rtw_8812au failed with error 1
> 

Got it. Let's take your method.