[PATCH v2 2/2] usb: mtu3: Add MT8195 MTU3 ip-sleep wakeup support

[AngeloGioacchino Del Regno]

Il 04/02/24 07:03, Chunfeng Yun (云春峰) ha scritto:
> On Mon, 2024-01-22 at 12:18 +0100, AngeloGioacchino Del Regno wrote:
>> Add support for the ip-sleep wakeup functionality on the three MTU3
>> controllers found on the MT8195 SoC.
>>
>> Signed-off-by: AngeloGioacchino Del Regno <
>> angelogioacchino.delregno at collabora.com>
>> ---
>>
>> Changes in v2:
>>   - Dropped unused definition for WC0_IS_EN_P1_95
>>
>>   drivers/usb/mtu3/mtu3_host.c | 30 ++++++++++++++++++++++++++++++
>>   1 file changed, 30 insertions(+)
>>
>> diff --git a/drivers/usb/mtu3/mtu3_host.c
>> b/drivers/usb/mtu3/mtu3_host.c
>> index 9f2be22af844..7c657ea2dabd 100644
>> --- a/drivers/usb/mtu3/mtu3_host.c
>> +++ b/drivers/usb/mtu3/mtu3_host.c
>> @@ -34,6 +34,18 @@
>>   #define WC0_SSUSB0_CDEN		BIT(6)
>>   #define WC0_IS_SPM_EN		BIT(1)
>>   
>> +/* mt8195 */
>> +#define PERI_WK_CTRL0_8195	0x04
>> +#define WC0_IS_P_95		BIT(30)	/* polarity */
>> +#define WC0_IS_C_95(x)		((u32)(((x) & 0x7) << 27))
>> +#define WC0_IS_EN_P3_95		BIT(26)
>> +#define WC0_IS_EN_P2_95		BIT(25)
>> +
>> +#define PERI_WK_CTRL1_8195	0x20
>> +#define WC1_IS_C_95(x)		((u32)(((x) & 0xf) << 28))
>> +#define WC1_IS_P_95		BIT(12)
>> +#define WC1_IS_EN_P0_95		BIT(6)
>> +
>>   /* mt2712 etc */
>>   #define PERI_SSUSB_SPM_CTRL	0x0
>>   #define SSC_IP_SLEEP_EN	BIT(4)
>> @@ -44,6 +56,9 @@ enum ssusb_uwk_vers {
>>   	SSUSB_UWK_V2,
>>   	SSUSB_UWK_V1_1 = 101,	/* specific revision 1.01 */
>>   	SSUSB_UWK_V1_2,		/* specific revision 1.02 */
>> +	SSUSB_UWK_V1_3,		/* mt8195 IP0 */
>> +	SSUSB_UWK_V1_5 = 105,	/* mt8195 IP2 */
>> +	SSUSB_UWK_V1_6,		/* mt8195 IP3 */
>>   };
>>   
>>   /*
>> @@ -70,6 +85,21 @@ static void ssusb_wakeup_ip_sleep_set(struct
>> ssusb_mtk *ssusb, bool enable)
>>   		msk = WC0_SSUSB0_CDEN | WC0_IS_SPM_EN;
>>   		val = enable ? msk : 0;
>>   		break;
>> +	case SSUSB_UWK_V1_3:
>> +		reg = ssusb->uwk_reg_base + PERI_WK_CTRL1_8195;
>> +		msk = WC1_IS_EN_P0_95 | WC1_IS_C_95(0xf) | WC1_IS_P_95;
>> +		val = enable ? (WC1_IS_EN_P0_95 | WC1_IS_C_95(0x1)) :
>> 0;
>> +		break;
>> +	case SSUSB_UWK_V1_5:
>> +		reg = ssusb->uwk_reg_base + PERI_WK_CTRL0_8195;
>> +		msk = WC0_IS_EN_P2_95 | WC0_IS_C_95(0x7) | WC0_IS_P_95;
>> +		val = enable ? (WC0_IS_EN_P2_95 | WC0_IS_C_95(0x1)) :
>> 0;
>> +		break;
>> +	case SSUSB_UWK_V1_6:
>> +		reg = ssusb->uwk_reg_base + PERI_WK_CTRL0_8195;
>> +		msk = WC0_IS_EN_P3_95 | WC0_IS_C_95(0x7) | WC0_IS_P_95;
>> +		val = enable ? (WC0_IS_EN_P3_95 | WC0_IS_C_95(0x1)) :
>> 0;
>> +		break;
>>   	case SSUSB_UWK_V2:
>>   		reg = ssusb->uwk_reg_base + PERI_SSUSB_SPM_CTRL;
>>   		msk = SSC_IP_SLEEP_EN | SSC_SPM_INT_EN;
> 
> which project will use ip-sleep wakeup for mt8195? only use device
> mode?
> 
> As I know, when use upstream code to support dual-role mode on mt8195,
> there is a bug caused by hw limitation;
> 
> 

This is required because:
  1. The device tree nodes for MT8195 were wrong (now they're correct), as in,
     there are three MTU3 controllers that must be described, as the device tree
     provides a description of the hardware, not a partial description of whatever
     one machine wants to use; and
  2. When the description of the hardware in DT is correct, even if Chromebooks are
     declaring dr_mode = "host", the IP sleep must come from MTU3 - otherwise there
     will be issues when trying to enter system sleep (as the system will be woken
     up immediately after trying to go to suspend); and
  3. Upstream does support the Genio 1200 EVK, and I'm also introducing a new board
     that is similar to that (Radxa NIO12L).

Besides, which bug are you talking about?

At least on Chromebooks, everything seems to be working just fine; maybe that's
because, on Cherry, dr_mode is forced to host.

Regards,
Angelo