diff mbox series

[v2,4/6] usb: typec: tcpm: Refactor tcpm_handle_vdm_request

Message ID 20200724174702.61754-4-hdegoede@redhat.com (mailing list archive)
State Mainlined
Commit 95b4d51c96a87cd760c2a4f27fb28a59a27b6368
Headers show
Series [v2,1/6] usb: typec: tcpm: Move mod_delayed_work(&port->vdm_state_machine) call into tcpm_queue_vdm() | expand

Commit Message

Hans de Goede July 24, 2020, 5:47 p.m. UTC
Refactor tcpm_handle_vdm_request and its tcpm_pd_svdm helper function so
that reporting the results of the vdm to the altmode-driver is separated
out into a clear separate step inside tcpm_handle_vdm_request, instead
of being scattered over various places inside the tcpm_pd_svdm helper.

This is a preparation patch for fixing an AB BA lock inversion between the
tcpm code and some altmode drivers.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
Changes in v2:
- Keep "if (adev && pdev)" checks as is instead of modifying them
---
 drivers/usb/typec/tcpm/tcpm.c | 76 ++++++++++++++++++++++-------------
 1 file changed, 48 insertions(+), 28 deletions(-)

Comments

Guenter Roeck July 25, 2020, 2:45 p.m. UTC | #1
On 7/24/20 10:47 AM, Hans de Goede wrote:
> Refactor tcpm_handle_vdm_request and its tcpm_pd_svdm helper function so
> that reporting the results of the vdm to the altmode-driver is separated
> out into a clear separate step inside tcpm_handle_vdm_request, instead
> of being scattered over various places inside the tcpm_pd_svdm helper.
> 
> This is a preparation patch for fixing an AB BA lock inversion between the
> tcpm code and some altmode drivers.
> 
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
> Changes in v2:
> - Keep "if (adev && pdev)" checks as is instead of modifying them
> ---
>  drivers/usb/typec/tcpm/tcpm.c | 76 ++++++++++++++++++++++-------------
>  1 file changed, 48 insertions(+), 28 deletions(-)
> 
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index ee239b54bcd8..03a0c083ee9a 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -159,6 +159,14 @@ enum pd_msg_request {
>  	PD_MSG_DATA_SOURCE_CAP,
>  };
>  
> +enum adev_actions {
> +	ADEV_NONE = 0,
> +	ADEV_NOTIFY_USB_AND_QUEUE_VDM,
> +	ADEV_QUEUE_VDM,
> +	ADEV_QUEUE_VDM_SEND_EXIT_MODE_ON_FAIL,
> +	ADEV_ATTENTION,
> +};
> +
>  /* Events from low level driver */
>  
>  #define TCPM_CC_EVENT		BIT(0)
> @@ -1078,10 +1086,10 @@ static void tcpm_register_partner_altmodes(struct tcpm_port *port)
>  
>  #define supports_modal(port)	PD_IDH_MODAL_SUPP((port)->partner_ident.id_header)
>  
> -static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
> -			u32 *response)
> +static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev,
> +			const u32 *p, int cnt, u32 *response,
> +			enum adev_actions *adev_action)
>  {
> -	struct typec_altmode *adev;
>  	struct typec_altmode *pdev;
>  	struct pd_mode_data *modep;
>  	int rlen = 0;
> @@ -1097,9 +1105,6 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>  
>  	modep = &port->mode_data;
>  
> -	adev = typec_match_altmode(port->port_altmode, ALTMODE_DISCOVERY_MAX,
> -				   PD_VDO_VID(p[0]), PD_VDO_OPOS(p[0]));
> -
>  	pdev = typec_match_altmode(port->partner_altmode, ALTMODE_DISCOVERY_MAX,
>  				   PD_VDO_VID(p[0]), PD_VDO_OPOS(p[0]));
>  
> @@ -1125,8 +1130,7 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>  			break;
>  		case CMD_ATTENTION:
>  			/* Attention command does not have response */
> -			if (adev)
> -				typec_altmode_attention(adev, p[1]);
> +			*adev_action = ADEV_ATTENTION;
>  			return 0;
>  		default:
>  			break;
> @@ -1180,23 +1184,15 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>  		case CMD_ENTER_MODE:
>  			if (adev && pdev) {

I must be missing something. Does this compile ? The 'adev' variable was removed above.
Maybe move the call to typec_altmode_update_active() into tcpm_handle_vdm_request()
instead ?

Thanks,
Guenter

>  				typec_altmode_update_active(pdev, true);
> -
> -				if (typec_altmode_vdm(adev, p[0], &p[1], cnt)) {
> -					response[0] = VDO(adev->svid, 1,
> -							  CMD_EXIT_MODE);
> -					response[0] |= VDO_OPOS(adev->mode);
> -					return 1;
> -				}
> +				*adev_action = ADEV_QUEUE_VDM_SEND_EXIT_MODE_ON_FAIL;
>  			}
>  			return 0;
>  		case CMD_EXIT_MODE:
>  			if (adev && pdev) {
>  				typec_altmode_update_active(pdev, false);
> -
>  				/* Back to USB Operation */
> -				WARN_ON(typec_altmode_notify(adev,
> -							     TYPEC_STATE_USB,
> -							     NULL));
> +				*adev_action = ADEV_NOTIFY_USB_AND_QUEUE_VDM;
> +				return 0;
>  			}
>  			break;
>  		default:
> @@ -1207,11 +1203,8 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>  		switch (cmd) {
>  		case CMD_ENTER_MODE:
>  			/* Back to USB Operation */
> -			if (adev)
> -				WARN_ON(typec_altmode_notify(adev,
> -							     TYPEC_STATE_USB,
> -							     NULL));
> -			break;
> +			*adev_action = ADEV_NOTIFY_USB_AND_QUEUE_VDM;
> +			return 0;
>  		default:
>  			break;
>  		}
> @@ -1221,15 +1214,15 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>  	}
>  
>  	/* Informing the alternate mode drivers about everything */
> -	if (adev)
> -		typec_altmode_vdm(adev, p[0], &p[1], cnt);
> -
> +	*adev_action = ADEV_QUEUE_VDM;
>  	return rlen;
>  }
>  
>  static void tcpm_handle_vdm_request(struct tcpm_port *port,
>  				    const __le32 *payload, int cnt)
>  {
> +	enum adev_actions adev_action = ADEV_NONE;
> +	struct typec_altmode *adev;
>  	u32 p[PD_MAX_PAYLOAD];
>  	u32 response[8] = { };
>  	int i, rlen = 0;
> @@ -1237,6 +1230,9 @@ static void tcpm_handle_vdm_request(struct tcpm_port *port,
>  	for (i = 0; i < cnt; i++)
>  		p[i] = le32_to_cpu(payload[i]);
>  
> +	adev = typec_match_altmode(port->port_altmode, ALTMODE_DISCOVERY_MAX,
> +				   PD_VDO_VID(p[0]), PD_VDO_OPOS(p[0]));
> +
>  	if (port->vdm_state == VDM_STATE_BUSY) {
>  		/* If UFP responded busy retry after timeout */
>  		if (PD_VDO_CMDT(p[0]) == CMDT_RSP_BUSY) {
> @@ -1251,7 +1247,31 @@ static void tcpm_handle_vdm_request(struct tcpm_port *port,
>  	}
>  
>  	if (PD_VDO_SVDM(p[0]))
> -		rlen = tcpm_pd_svdm(port, p, cnt, response);
> +		rlen = tcpm_pd_svdm(port, adev, p, cnt, response, &adev_action);
> +
> +	if (adev) {
> +		switch (adev_action) {
> +		case ADEV_NONE:
> +			break;
> +		case ADEV_NOTIFY_USB_AND_QUEUE_VDM:
> +			WARN_ON(typec_altmode_notify(adev, TYPEC_STATE_USB, NULL));
> +			typec_altmode_vdm(adev, p[0], &p[1], cnt);
> +			break;
> +		case ADEV_QUEUE_VDM:
> +			typec_altmode_vdm(adev, p[0], &p[1], cnt);
> +			break;
> +		case ADEV_QUEUE_VDM_SEND_EXIT_MODE_ON_FAIL:
> +			if (typec_altmode_vdm(adev, p[0], &p[1], cnt)) {
> +				response[0] = VDO(adev->svid, 1, CMD_EXIT_MODE);
> +				response[0] |= VDO_OPOS(adev->mode);
> +				rlen = 1;
> +			}
> +			break;
> +		case ADEV_ATTENTION:
> +			typec_altmode_attention(adev, p[1]);
> +			break;
> +		}
> +	}
>  
>  	if (rlen > 0)
>  		tcpm_queue_vdm(port, response[0], &response[1], rlen - 1);
>
Hans de Goede July 26, 2020, 10:58 a.m. UTC | #2
Hi,

On 7/25/20 4:45 PM, Guenter Roeck wrote:
> On 7/24/20 10:47 AM, Hans de Goede wrote:
>> Refactor tcpm_handle_vdm_request and its tcpm_pd_svdm helper function so
>> that reporting the results of the vdm to the altmode-driver is separated
>> out into a clear separate step inside tcpm_handle_vdm_request, instead
>> of being scattered over various places inside the tcpm_pd_svdm helper.
>>
>> This is a preparation patch for fixing an AB BA lock inversion between the
>> tcpm code and some altmode drivers.
>>
>> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
>> ---
>> Changes in v2:
>> - Keep "if (adev && pdev)" checks as is instead of modifying them
>> ---
>>   drivers/usb/typec/tcpm/tcpm.c | 76 ++++++++++++++++++++++-------------
>>   1 file changed, 48 insertions(+), 28 deletions(-)
>>
>> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
>> index ee239b54bcd8..03a0c083ee9a 100644
>> --- a/drivers/usb/typec/tcpm/tcpm.c
>> +++ b/drivers/usb/typec/tcpm/tcpm.c
>> @@ -159,6 +159,14 @@ enum pd_msg_request {
>>   	PD_MSG_DATA_SOURCE_CAP,
>>   };
>>   
>> +enum adev_actions {
>> +	ADEV_NONE = 0,
>> +	ADEV_NOTIFY_USB_AND_QUEUE_VDM,
>> +	ADEV_QUEUE_VDM,
>> +	ADEV_QUEUE_VDM_SEND_EXIT_MODE_ON_FAIL,
>> +	ADEV_ATTENTION,
>> +};
>> +
>>   /* Events from low level driver */
>>   
>>   #define TCPM_CC_EVENT		BIT(0)
>> @@ -1078,10 +1086,10 @@ static void tcpm_register_partner_altmodes(struct tcpm_port *port)
>>   
>>   #define supports_modal(port)	PD_IDH_MODAL_SUPP((port)->partner_ident.id_header)
>>   
>> -static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>> -			u32 *response)
>> +static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev,
>> +			const u32 *p, int cnt, u32 *response,
>> +			enum adev_actions *adev_action)
>>   {
>> -	struct typec_altmode *adev;
>>   	struct typec_altmode *pdev;
>>   	struct pd_mode_data *modep;
>>   	int rlen = 0;
>> @@ -1097,9 +1105,6 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>>   
>>   	modep = &port->mode_data;
>>   
>> -	adev = typec_match_altmode(port->port_altmode, ALTMODE_DISCOVERY_MAX,
>> -				   PD_VDO_VID(p[0]), PD_VDO_OPOS(p[0]));
>> -
>>   	pdev = typec_match_altmode(port->partner_altmode, ALTMODE_DISCOVERY_MAX,
>>   				   PD_VDO_VID(p[0]), PD_VDO_OPOS(p[0]));
>>   
>> @@ -1125,8 +1130,7 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>>   			break;
>>   		case CMD_ATTENTION:
>>   			/* Attention command does not have response */
>> -			if (adev)
>> -				typec_altmode_attention(adev, p[1]);
>> +			*adev_action = ADEV_ATTENTION;
>>   			return 0;
>>   		default:
>>   			break;
>> @@ -1180,23 +1184,15 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>>   		case CMD_ENTER_MODE:
>>   			if (adev && pdev) {
> 
> I must be missing something. Does this compile ? The 'adev' variable was removed above.
> Maybe move the call to typec_altmode_update_active() into tcpm_handle_vdm_request()
> instead ?

Yes it compiles. The adev variable is now a function parameter, since
we already to the lookup for it in tcpm_handle_vdm_request() now,
I'm simply passing it along here.

Regards,

Hans



>>   				typec_altmode_update_active(pdev, true);
>> -
>> -				if (typec_altmode_vdm(adev, p[0], &p[1], cnt)) {
>> -					response[0] = VDO(adev->svid, 1,
>> -							  CMD_EXIT_MODE);
>> -					response[0] |= VDO_OPOS(adev->mode);
>> -					return 1;
>> -				}
>> +				*adev_action = ADEV_QUEUE_VDM_SEND_EXIT_MODE_ON_FAIL;
>>   			}
>>   			return 0;
>>   		case CMD_EXIT_MODE:
>>   			if (adev && pdev) {
>>   				typec_altmode_update_active(pdev, false);
>> -
>>   				/* Back to USB Operation */
>> -				WARN_ON(typec_altmode_notify(adev,
>> -							     TYPEC_STATE_USB,
>> -							     NULL));
>> +				*adev_action = ADEV_NOTIFY_USB_AND_QUEUE_VDM;
>> +				return 0;
>>   			}
>>   			break;
>>   		default:
>> @@ -1207,11 +1203,8 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>>   		switch (cmd) {
>>   		case CMD_ENTER_MODE:
>>   			/* Back to USB Operation */
>> -			if (adev)
>> -				WARN_ON(typec_altmode_notify(adev,
>> -							     TYPEC_STATE_USB,
>> -							     NULL));
>> -			break;
>> +			*adev_action = ADEV_NOTIFY_USB_AND_QUEUE_VDM;
>> +			return 0;
>>   		default:
>>   			break;
>>   		}
>> @@ -1221,15 +1214,15 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>>   	}
>>   
>>   	/* Informing the alternate mode drivers about everything */
>> -	if (adev)
>> -		typec_altmode_vdm(adev, p[0], &p[1], cnt);
>> -
>> +	*adev_action = ADEV_QUEUE_VDM;
>>   	return rlen;
>>   }
>>   
>>   static void tcpm_handle_vdm_request(struct tcpm_port *port,
>>   				    const __le32 *payload, int cnt)
>>   {
>> +	enum adev_actions adev_action = ADEV_NONE;
>> +	struct typec_altmode *adev;
>>   	u32 p[PD_MAX_PAYLOAD];
>>   	u32 response[8] = { };
>>   	int i, rlen = 0;
>> @@ -1237,6 +1230,9 @@ static void tcpm_handle_vdm_request(struct tcpm_port *port,
>>   	for (i = 0; i < cnt; i++)
>>   		p[i] = le32_to_cpu(payload[i]);
>>   
>> +	adev = typec_match_altmode(port->port_altmode, ALTMODE_DISCOVERY_MAX,
>> +				   PD_VDO_VID(p[0]), PD_VDO_OPOS(p[0]));
>> +
>>   	if (port->vdm_state == VDM_STATE_BUSY) {
>>   		/* If UFP responded busy retry after timeout */
>>   		if (PD_VDO_CMDT(p[0]) == CMDT_RSP_BUSY) {
>> @@ -1251,7 +1247,31 @@ static void tcpm_handle_vdm_request(struct tcpm_port *port,
>>   	}
>>   
>>   	if (PD_VDO_SVDM(p[0]))
>> -		rlen = tcpm_pd_svdm(port, p, cnt, response);
>> +		rlen = tcpm_pd_svdm(port, adev, p, cnt, response, &adev_action);
>> +
>> +	if (adev) {
>> +		switch (adev_action) {
>> +		case ADEV_NONE:
>> +			break;
>> +		case ADEV_NOTIFY_USB_AND_QUEUE_VDM:
>> +			WARN_ON(typec_altmode_notify(adev, TYPEC_STATE_USB, NULL));
>> +			typec_altmode_vdm(adev, p[0], &p[1], cnt);
>> +			break;
>> +		case ADEV_QUEUE_VDM:
>> +			typec_altmode_vdm(adev, p[0], &p[1], cnt);
>> +			break;
>> +		case ADEV_QUEUE_VDM_SEND_EXIT_MODE_ON_FAIL:
>> +			if (typec_altmode_vdm(adev, p[0], &p[1], cnt)) {
>> +				response[0] = VDO(adev->svid, 1, CMD_EXIT_MODE);
>> +				response[0] |= VDO_OPOS(adev->mode);
>> +				rlen = 1;
>> +			}
>> +			break;
>> +		case ADEV_ATTENTION:
>> +			typec_altmode_attention(adev, p[1]);
>> +			break;
>> +		}
>> +	}
>>   
>>   	if (rlen > 0)
>>   		tcpm_queue_vdm(port, response[0], &response[1], rlen - 1);
>>
>
Guenter Roeck July 26, 2020, 1:22 p.m. UTC | #3
On 7/26/20 3:58 AM, Hans de Goede wrote:
> Hi,
> 
> On 7/25/20 4:45 PM, Guenter Roeck wrote:
>> On 7/24/20 10:47 AM, Hans de Goede wrote:
>>> Refactor tcpm_handle_vdm_request and its tcpm_pd_svdm helper function so
>>> that reporting the results of the vdm to the altmode-driver is separated
>>> out into a clear separate step inside tcpm_handle_vdm_request, instead
>>> of being scattered over various places inside the tcpm_pd_svdm helper.
>>>
>>> This is a preparation patch for fixing an AB BA lock inversion between the
>>> tcpm code and some altmode drivers.
>>>
>>> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
>>> ---
>>> Changes in v2:
>>> - Keep "if (adev && pdev)" checks as is instead of modifying them
>>> ---
>>>   drivers/usb/typec/tcpm/tcpm.c | 76 ++++++++++++++++++++++-------------
>>>   1 file changed, 48 insertions(+), 28 deletions(-)
>>>
>>> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
>>> index ee239b54bcd8..03a0c083ee9a 100644
>>> --- a/drivers/usb/typec/tcpm/tcpm.c
>>> +++ b/drivers/usb/typec/tcpm/tcpm.c
>>> @@ -159,6 +159,14 @@ enum pd_msg_request {
>>>       PD_MSG_DATA_SOURCE_CAP,
>>>   };
>>>   +enum adev_actions {
>>> +    ADEV_NONE = 0,
>>> +    ADEV_NOTIFY_USB_AND_QUEUE_VDM,
>>> +    ADEV_QUEUE_VDM,
>>> +    ADEV_QUEUE_VDM_SEND_EXIT_MODE_ON_FAIL,
>>> +    ADEV_ATTENTION,
>>> +};
>>> +
>>>   /* Events from low level driver */
>>>     #define TCPM_CC_EVENT        BIT(0)
>>> @@ -1078,10 +1086,10 @@ static void tcpm_register_partner_altmodes(struct tcpm_port *port)
>>>     #define supports_modal(port)    PD_IDH_MODAL_SUPP((port)->partner_ident.id_header)
>>>   -static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>>> -            u32 *response)
>>> +static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev,
>>> +            const u32 *p, int cnt, u32 *response,
>>> +            enum adev_actions *adev_action)
>>>   {
>>> -    struct typec_altmode *adev;
>>>       struct typec_altmode *pdev;
>>>       struct pd_mode_data *modep;
>>>       int rlen = 0;
>>> @@ -1097,9 +1105,6 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>>>         modep = &port->mode_data;
>>>   -    adev = typec_match_altmode(port->port_altmode, ALTMODE_DISCOVERY_MAX,
>>> -                   PD_VDO_VID(p[0]), PD_VDO_OPOS(p[0]));
>>> -
>>>       pdev = typec_match_altmode(port->partner_altmode, ALTMODE_DISCOVERY_MAX,
>>>                      PD_VDO_VID(p[0]), PD_VDO_OPOS(p[0]));
>>>   @@ -1125,8 +1130,7 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>>>               break;
>>>           case CMD_ATTENTION:
>>>               /* Attention command does not have response */
>>> -            if (adev)
>>> -                typec_altmode_attention(adev, p[1]);
>>> +            *adev_action = ADEV_ATTENTION;
>>>               return 0;
>>>           default:
>>>               break;
>>> @@ -1180,23 +1184,15 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>>>           case CMD_ENTER_MODE:
>>>               if (adev && pdev) {
>>
>> I must be missing something. Does this compile ? The 'adev' variable was removed above.
>> Maybe move the call to typec_altmode_update_active() into tcpm_handle_vdm_request()
>> instead ?
> 
> Yes it compiles. The adev variable is now a function parameter, since
> we already to the lookup for it in tcpm_handle_vdm_request() now,
> I'm simply passing it along here.
> 

Thanks for the clarification, and sorry I missed that.

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> Regards,
> 
> Hans
> 
> 
> 
>>>                   typec_altmode_update_active(pdev, true);
>>> -
>>> -                if (typec_altmode_vdm(adev, p[0], &p[1], cnt)) {
>>> -                    response[0] = VDO(adev->svid, 1,
>>> -                              CMD_EXIT_MODE);
>>> -                    response[0] |= VDO_OPOS(adev->mode);
>>> -                    return 1;
>>> -                }
>>> +                *adev_action = ADEV_QUEUE_VDM_SEND_EXIT_MODE_ON_FAIL;
>>>               }
>>>               return 0;
>>>           case CMD_EXIT_MODE:
>>>               if (adev && pdev) {
>>>                   typec_altmode_update_active(pdev, false);
>>> -
>>>                   /* Back to USB Operation */
>>> -                WARN_ON(typec_altmode_notify(adev,
>>> -                                 TYPEC_STATE_USB,
>>> -                                 NULL));
>>> +                *adev_action = ADEV_NOTIFY_USB_AND_QUEUE_VDM;
>>> +                return 0;
>>>               }
>>>               break;
>>>           default:
>>> @@ -1207,11 +1203,8 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>>>           switch (cmd) {
>>>           case CMD_ENTER_MODE:
>>>               /* Back to USB Operation */
>>> -            if (adev)
>>> -                WARN_ON(typec_altmode_notify(adev,
>>> -                                 TYPEC_STATE_USB,
>>> -                                 NULL));
>>> -            break;
>>> +            *adev_action = ADEV_NOTIFY_USB_AND_QUEUE_VDM;
>>> +            return 0;
>>>           default:
>>>               break;
>>>           }
>>> @@ -1221,15 +1214,15 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>>>       }
>>>         /* Informing the alternate mode drivers about everything */
>>> -    if (adev)
>>> -        typec_altmode_vdm(adev, p[0], &p[1], cnt);
>>> -
>>> +    *adev_action = ADEV_QUEUE_VDM;
>>>       return rlen;
>>>   }
>>>     static void tcpm_handle_vdm_request(struct tcpm_port *port,
>>>                       const __le32 *payload, int cnt)
>>>   {
>>> +    enum adev_actions adev_action = ADEV_NONE;
>>> +    struct typec_altmode *adev;
>>>       u32 p[PD_MAX_PAYLOAD];
>>>       u32 response[8] = { };
>>>       int i, rlen = 0;
>>> @@ -1237,6 +1230,9 @@ static void tcpm_handle_vdm_request(struct tcpm_port *port,
>>>       for (i = 0; i < cnt; i++)
>>>           p[i] = le32_to_cpu(payload[i]);
>>>   +    adev = typec_match_altmode(port->port_altmode, ALTMODE_DISCOVERY_MAX,
>>> +                   PD_VDO_VID(p[0]), PD_VDO_OPOS(p[0]));
>>> +
>>>       if (port->vdm_state == VDM_STATE_BUSY) {
>>>           /* If UFP responded busy retry after timeout */
>>>           if (PD_VDO_CMDT(p[0]) == CMDT_RSP_BUSY) {
>>> @@ -1251,7 +1247,31 @@ static void tcpm_handle_vdm_request(struct tcpm_port *port,
>>>       }
>>>         if (PD_VDO_SVDM(p[0]))
>>> -        rlen = tcpm_pd_svdm(port, p, cnt, response);
>>> +        rlen = tcpm_pd_svdm(port, adev, p, cnt, response, &adev_action);
>>> +
>>> +    if (adev) {
>>> +        switch (adev_action) {
>>> +        case ADEV_NONE:
>>> +            break;
>>> +        case ADEV_NOTIFY_USB_AND_QUEUE_VDM:
>>> +            WARN_ON(typec_altmode_notify(adev, TYPEC_STATE_USB, NULL));
>>> +            typec_altmode_vdm(adev, p[0], &p[1], cnt);
>>> +            break;
>>> +        case ADEV_QUEUE_VDM:
>>> +            typec_altmode_vdm(adev, p[0], &p[1], cnt);
>>> +            break;
>>> +        case ADEV_QUEUE_VDM_SEND_EXIT_MODE_ON_FAIL:
>>> +            if (typec_altmode_vdm(adev, p[0], &p[1], cnt)) {
>>> +                response[0] = VDO(adev->svid, 1, CMD_EXIT_MODE);
>>> +                response[0] |= VDO_OPOS(adev->mode);
>>> +                rlen = 1;
>>> +            }
>>> +            break;
>>> +        case ADEV_ATTENTION:
>>> +            typec_altmode_attention(adev, p[1]);
>>> +            break;
>>> +        }
>>> +    }
>>>         if (rlen > 0)
>>>           tcpm_queue_vdm(port, response[0], &response[1], rlen - 1);
>>>
>>
>
Heikki Krogerus July 28, 2020, 1:06 p.m. UTC | #4
On Fri, Jul 24, 2020 at 07:47:00PM +0200, Hans de Goede wrote:
> Refactor tcpm_handle_vdm_request and its tcpm_pd_svdm helper function so
> that reporting the results of the vdm to the altmode-driver is separated
> out into a clear separate step inside tcpm_handle_vdm_request, instead
> of being scattered over various places inside the tcpm_pd_svdm helper.
> 
> This is a preparation patch for fixing an AB BA lock inversion between the
> tcpm code and some altmode drivers.
> 
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>

Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>

> ---
> Changes in v2:
> - Keep "if (adev && pdev)" checks as is instead of modifying them
> ---
>  drivers/usb/typec/tcpm/tcpm.c | 76 ++++++++++++++++++++++-------------
>  1 file changed, 48 insertions(+), 28 deletions(-)
> 
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index ee239b54bcd8..03a0c083ee9a 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -159,6 +159,14 @@ enum pd_msg_request {
>  	PD_MSG_DATA_SOURCE_CAP,
>  };
>  
> +enum adev_actions {
> +	ADEV_NONE = 0,
> +	ADEV_NOTIFY_USB_AND_QUEUE_VDM,
> +	ADEV_QUEUE_VDM,
> +	ADEV_QUEUE_VDM_SEND_EXIT_MODE_ON_FAIL,
> +	ADEV_ATTENTION,
> +};
> +
>  /* Events from low level driver */
>  
>  #define TCPM_CC_EVENT		BIT(0)
> @@ -1078,10 +1086,10 @@ static void tcpm_register_partner_altmodes(struct tcpm_port *port)
>  
>  #define supports_modal(port)	PD_IDH_MODAL_SUPP((port)->partner_ident.id_header)
>  
> -static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
> -			u32 *response)
> +static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev,
> +			const u32 *p, int cnt, u32 *response,
> +			enum adev_actions *adev_action)
>  {
> -	struct typec_altmode *adev;
>  	struct typec_altmode *pdev;
>  	struct pd_mode_data *modep;
>  	int rlen = 0;
> @@ -1097,9 +1105,6 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>  
>  	modep = &port->mode_data;
>  
> -	adev = typec_match_altmode(port->port_altmode, ALTMODE_DISCOVERY_MAX,
> -				   PD_VDO_VID(p[0]), PD_VDO_OPOS(p[0]));
> -
>  	pdev = typec_match_altmode(port->partner_altmode, ALTMODE_DISCOVERY_MAX,
>  				   PD_VDO_VID(p[0]), PD_VDO_OPOS(p[0]));
>  
> @@ -1125,8 +1130,7 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>  			break;
>  		case CMD_ATTENTION:
>  			/* Attention command does not have response */
> -			if (adev)
> -				typec_altmode_attention(adev, p[1]);
> +			*adev_action = ADEV_ATTENTION;
>  			return 0;
>  		default:
>  			break;
> @@ -1180,23 +1184,15 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>  		case CMD_ENTER_MODE:
>  			if (adev && pdev) {
>  				typec_altmode_update_active(pdev, true);
> -
> -				if (typec_altmode_vdm(adev, p[0], &p[1], cnt)) {
> -					response[0] = VDO(adev->svid, 1,
> -							  CMD_EXIT_MODE);
> -					response[0] |= VDO_OPOS(adev->mode);
> -					return 1;
> -				}
> +				*adev_action = ADEV_QUEUE_VDM_SEND_EXIT_MODE_ON_FAIL;
>  			}
>  			return 0;
>  		case CMD_EXIT_MODE:
>  			if (adev && pdev) {
>  				typec_altmode_update_active(pdev, false);
> -
>  				/* Back to USB Operation */
> -				WARN_ON(typec_altmode_notify(adev,
> -							     TYPEC_STATE_USB,
> -							     NULL));
> +				*adev_action = ADEV_NOTIFY_USB_AND_QUEUE_VDM;
> +				return 0;
>  			}
>  			break;
>  		default:
> @@ -1207,11 +1203,8 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>  		switch (cmd) {
>  		case CMD_ENTER_MODE:
>  			/* Back to USB Operation */
> -			if (adev)
> -				WARN_ON(typec_altmode_notify(adev,
> -							     TYPEC_STATE_USB,
> -							     NULL));
> -			break;
> +			*adev_action = ADEV_NOTIFY_USB_AND_QUEUE_VDM;
> +			return 0;
>  		default:
>  			break;
>  		}
> @@ -1221,15 +1214,15 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
>  	}
>  
>  	/* Informing the alternate mode drivers about everything */
> -	if (adev)
> -		typec_altmode_vdm(adev, p[0], &p[1], cnt);
> -
> +	*adev_action = ADEV_QUEUE_VDM;
>  	return rlen;
>  }
>  
>  static void tcpm_handle_vdm_request(struct tcpm_port *port,
>  				    const __le32 *payload, int cnt)
>  {
> +	enum adev_actions adev_action = ADEV_NONE;
> +	struct typec_altmode *adev;
>  	u32 p[PD_MAX_PAYLOAD];
>  	u32 response[8] = { };
>  	int i, rlen = 0;
> @@ -1237,6 +1230,9 @@ static void tcpm_handle_vdm_request(struct tcpm_port *port,
>  	for (i = 0; i < cnt; i++)
>  		p[i] = le32_to_cpu(payload[i]);
>  
> +	adev = typec_match_altmode(port->port_altmode, ALTMODE_DISCOVERY_MAX,
> +				   PD_VDO_VID(p[0]), PD_VDO_OPOS(p[0]));
> +
>  	if (port->vdm_state == VDM_STATE_BUSY) {
>  		/* If UFP responded busy retry after timeout */
>  		if (PD_VDO_CMDT(p[0]) == CMDT_RSP_BUSY) {
> @@ -1251,7 +1247,31 @@ static void tcpm_handle_vdm_request(struct tcpm_port *port,
>  	}
>  
>  	if (PD_VDO_SVDM(p[0]))
> -		rlen = tcpm_pd_svdm(port, p, cnt, response);
> +		rlen = tcpm_pd_svdm(port, adev, p, cnt, response, &adev_action);
> +
> +	if (adev) {
> +		switch (adev_action) {
> +		case ADEV_NONE:
> +			break;
> +		case ADEV_NOTIFY_USB_AND_QUEUE_VDM:
> +			WARN_ON(typec_altmode_notify(adev, TYPEC_STATE_USB, NULL));
> +			typec_altmode_vdm(adev, p[0], &p[1], cnt);
> +			break;
> +		case ADEV_QUEUE_VDM:
> +			typec_altmode_vdm(adev, p[0], &p[1], cnt);
> +			break;
> +		case ADEV_QUEUE_VDM_SEND_EXIT_MODE_ON_FAIL:
> +			if (typec_altmode_vdm(adev, p[0], &p[1], cnt)) {
> +				response[0] = VDO(adev->svid, 1, CMD_EXIT_MODE);
> +				response[0] |= VDO_OPOS(adev->mode);
> +				rlen = 1;
> +			}
> +			break;
> +		case ADEV_ATTENTION:
> +			typec_altmode_attention(adev, p[1]);
> +			break;
> +		}
> +	}
>  
>  	if (rlen > 0)
>  		tcpm_queue_vdm(port, response[0], &response[1], rlen - 1);
> -- 
> 2.26.2

thanks,
diff mbox series

Patch

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index ee239b54bcd8..03a0c083ee9a 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -159,6 +159,14 @@  enum pd_msg_request {
 	PD_MSG_DATA_SOURCE_CAP,
 };
 
+enum adev_actions {
+	ADEV_NONE = 0,
+	ADEV_NOTIFY_USB_AND_QUEUE_VDM,
+	ADEV_QUEUE_VDM,
+	ADEV_QUEUE_VDM_SEND_EXIT_MODE_ON_FAIL,
+	ADEV_ATTENTION,
+};
+
 /* Events from low level driver */
 
 #define TCPM_CC_EVENT		BIT(0)
@@ -1078,10 +1086,10 @@  static void tcpm_register_partner_altmodes(struct tcpm_port *port)
 
 #define supports_modal(port)	PD_IDH_MODAL_SUPP((port)->partner_ident.id_header)
 
-static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
-			u32 *response)
+static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev,
+			const u32 *p, int cnt, u32 *response,
+			enum adev_actions *adev_action)
 {
-	struct typec_altmode *adev;
 	struct typec_altmode *pdev;
 	struct pd_mode_data *modep;
 	int rlen = 0;
@@ -1097,9 +1105,6 @@  static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
 
 	modep = &port->mode_data;
 
-	adev = typec_match_altmode(port->port_altmode, ALTMODE_DISCOVERY_MAX,
-				   PD_VDO_VID(p[0]), PD_VDO_OPOS(p[0]));
-
 	pdev = typec_match_altmode(port->partner_altmode, ALTMODE_DISCOVERY_MAX,
 				   PD_VDO_VID(p[0]), PD_VDO_OPOS(p[0]));
 
@@ -1125,8 +1130,7 @@  static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
 			break;
 		case CMD_ATTENTION:
 			/* Attention command does not have response */
-			if (adev)
-				typec_altmode_attention(adev, p[1]);
+			*adev_action = ADEV_ATTENTION;
 			return 0;
 		default:
 			break;
@@ -1180,23 +1184,15 @@  static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
 		case CMD_ENTER_MODE:
 			if (adev && pdev) {
 				typec_altmode_update_active(pdev, true);
-
-				if (typec_altmode_vdm(adev, p[0], &p[1], cnt)) {
-					response[0] = VDO(adev->svid, 1,
-							  CMD_EXIT_MODE);
-					response[0] |= VDO_OPOS(adev->mode);
-					return 1;
-				}
+				*adev_action = ADEV_QUEUE_VDM_SEND_EXIT_MODE_ON_FAIL;
 			}
 			return 0;
 		case CMD_EXIT_MODE:
 			if (adev && pdev) {
 				typec_altmode_update_active(pdev, false);
-
 				/* Back to USB Operation */
-				WARN_ON(typec_altmode_notify(adev,
-							     TYPEC_STATE_USB,
-							     NULL));
+				*adev_action = ADEV_NOTIFY_USB_AND_QUEUE_VDM;
+				return 0;
 			}
 			break;
 		default:
@@ -1207,11 +1203,8 @@  static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
 		switch (cmd) {
 		case CMD_ENTER_MODE:
 			/* Back to USB Operation */
-			if (adev)
-				WARN_ON(typec_altmode_notify(adev,
-							     TYPEC_STATE_USB,
-							     NULL));
-			break;
+			*adev_action = ADEV_NOTIFY_USB_AND_QUEUE_VDM;
+			return 0;
 		default:
 			break;
 		}
@@ -1221,15 +1214,15 @@  static int tcpm_pd_svdm(struct tcpm_port *port, const u32 *p, int cnt,
 	}
 
 	/* Informing the alternate mode drivers about everything */
-	if (adev)
-		typec_altmode_vdm(adev, p[0], &p[1], cnt);
-
+	*adev_action = ADEV_QUEUE_VDM;
 	return rlen;
 }
 
 static void tcpm_handle_vdm_request(struct tcpm_port *port,
 				    const __le32 *payload, int cnt)
 {
+	enum adev_actions adev_action = ADEV_NONE;
+	struct typec_altmode *adev;
 	u32 p[PD_MAX_PAYLOAD];
 	u32 response[8] = { };
 	int i, rlen = 0;
@@ -1237,6 +1230,9 @@  static void tcpm_handle_vdm_request(struct tcpm_port *port,
 	for (i = 0; i < cnt; i++)
 		p[i] = le32_to_cpu(payload[i]);
 
+	adev = typec_match_altmode(port->port_altmode, ALTMODE_DISCOVERY_MAX,
+				   PD_VDO_VID(p[0]), PD_VDO_OPOS(p[0]));
+
 	if (port->vdm_state == VDM_STATE_BUSY) {
 		/* If UFP responded busy retry after timeout */
 		if (PD_VDO_CMDT(p[0]) == CMDT_RSP_BUSY) {
@@ -1251,7 +1247,31 @@  static void tcpm_handle_vdm_request(struct tcpm_port *port,
 	}
 
 	if (PD_VDO_SVDM(p[0]))
-		rlen = tcpm_pd_svdm(port, p, cnt, response);
+		rlen = tcpm_pd_svdm(port, adev, p, cnt, response, &adev_action);
+
+	if (adev) {
+		switch (adev_action) {
+		case ADEV_NONE:
+			break;
+		case ADEV_NOTIFY_USB_AND_QUEUE_VDM:
+			WARN_ON(typec_altmode_notify(adev, TYPEC_STATE_USB, NULL));
+			typec_altmode_vdm(adev, p[0], &p[1], cnt);
+			break;
+		case ADEV_QUEUE_VDM:
+			typec_altmode_vdm(adev, p[0], &p[1], cnt);
+			break;
+		case ADEV_QUEUE_VDM_SEND_EXIT_MODE_ON_FAIL:
+			if (typec_altmode_vdm(adev, p[0], &p[1], cnt)) {
+				response[0] = VDO(adev->svid, 1, CMD_EXIT_MODE);
+				response[0] |= VDO_OPOS(adev->mode);
+				rlen = 1;
+			}
+			break;
+		case ADEV_ATTENTION:
+			typec_altmode_attention(adev, p[1]);
+			break;
+		}
+	}
 
 	if (rlen > 0)
 		tcpm_queue_vdm(port, response[0], &response[1], rlen - 1);