[PATCH] usb: typec: tcpm: Fix sink PDO starting index for PPS APDO selection

[PATCH] usb: typec: tcpm: Fix sink PDO starting index for PPS APDO selection

[Adam Thomson]

There is a bug in the sink PDO search code when trying to select
a PPS APDO. The current code actually sets the starting index for
searching to whatever value 'i' is, rather than choosing index 1
to avoid the first PDO (always 5V fixed). As a result, for sources
which support PPS but whose PPS APDO index does not match with the
supporting sink PPS APDO index for the platform, no valid PPS APDO
will be found so this feature will not be permitted.

Sadly in testing, both Source and Sink capabilities matched up and
this was missed. Code is now updated to correctly set the start
index to 1, and testing with additional PPS capable sources show
this to work as expected.

Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
---
 drivers/usb/typec/tcpm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/typec/tcpm.c b/drivers/usb/typec/tcpm.c
index 74e0cda..4f1f421 100644
--- a/drivers/usb/typec/tcpm.c
+++ b/drivers/usb/typec/tcpm.c
@@ -2238,7 +2238,7 @@ static unsigned int tcpm_pd_select_pps_apdo(struct tcpm_port *port)
 			 * PPS APDO. Again skip the first sink PDO as this will
 			 * always be 5V 3A.
 			 */
-			for (j = i; j < port->nr_snk_pdo; j++) {
+			for (j = 1; j < port->nr_snk_pdo; j++) {
 				pdo = port->snk_pdo[j];
 
 				switch (pdo_type(pdo)) {
-- 
1.9.1

Re: [PATCH] usb: typec: tcpm: Fix sink PDO starting index for PPS APDO selection

[Guenter Roeck]

On Tue, Jul 17, 2018 at 03:36:19PM +0100, Adam Thomson wrote:
> There is a bug in the sink PDO search code when trying to select
> a PPS APDO. The current code actually sets the starting index for
> searching to whatever value 'i' is, rather than choosing index 1
> to avoid the first PDO (always 5V fixed). As a result, for sources
> which support PPS but whose PPS APDO index does not match with the
> supporting sink PPS APDO index for the platform, no valid PPS APDO
> will be found so this feature will not be permitted.
> 
> Sadly in testing, both Source and Sink capabilities matched up and
> this was missed. Code is now updated to correctly set the start
> index to 1, and testing with additional PPS capable sources show
> this to work as expected.
> 
> Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>

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

> ---
>  drivers/usb/typec/tcpm.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/typec/tcpm.c b/drivers/usb/typec/tcpm.c
> index 74e0cda..4f1f421 100644
> --- a/drivers/usb/typec/tcpm.c
> +++ b/drivers/usb/typec/tcpm.c
> @@ -2238,7 +2238,7 @@ static unsigned int tcpm_pd_select_pps_apdo(struct tcpm_port *port)
>  			 * PPS APDO. Again skip the first sink PDO as this will
>  			 * always be 5V 3A.
>  			 */
> -			for (j = i; j < port->nr_snk_pdo; j++) {
> +			for (j = 1; j < port->nr_snk_pdo; j++) {
>  				pdo = port->snk_pdo[j];
>  
>  				switch (pdo_type(pdo)) {
> -- 
> 1.9.1
> 

Re: [PATCH] usb: typec: tcpm: Fix sink PDO starting index for PPS APDO selection

[Heikki Krogerus]

On Tue, Jul 17, 2018 at 03:36:19PM +0100, Adam Thomson wrote:
> There is a bug in the sink PDO search code when trying to select
> a PPS APDO. The current code actually sets the starting index for
> searching to whatever value 'i' is, rather than choosing index 1
> to avoid the first PDO (always 5V fixed). As a result, for sources
> which support PPS but whose PPS APDO index does not match with the
> supporting sink PPS APDO index for the platform, no valid PPS APDO
> will be found so this feature will not be permitted.
> 
> Sadly in testing, both Source and Sink capabilities matched up and
> this was missed. Code is now updated to correctly set the start
> index to 1, and testing with additional PPS capable sources show
> this to work as expected.
> 
> Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>

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

> ---
>  drivers/usb/typec/tcpm.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/typec/tcpm.c b/drivers/usb/typec/tcpm.c
> index 74e0cda..4f1f421 100644
> --- a/drivers/usb/typec/tcpm.c
> +++ b/drivers/usb/typec/tcpm.c
> @@ -2238,7 +2238,7 @@ static unsigned int tcpm_pd_select_pps_apdo(struct tcpm_port *port)
>  			 * PPS APDO. Again skip the first sink PDO as this will
>  			 * always be 5V 3A.
>  			 */
> -			for (j = i; j < port->nr_snk_pdo; j++) {
> +			for (j = 1; j < port->nr_snk_pdo; j++) {
>  				pdo = port->snk_pdo[j];
>  
>  				switch (pdo_type(pdo)) {

Thanks,

-- 
heikki

Re: [PATCH] usb: typec: tcpm: Fix sink PDO starting index for PPS APDO selection

[Greg Kroah-Hartman]

On Tue, Jul 17, 2018 at 03:36:19PM +0100, Adam Thomson wrote:
> There is a bug in the sink PDO search code when trying to select
> a PPS APDO. The current code actually sets the starting index for
> searching to whatever value 'i' is, rather than choosing index 1
> to avoid the first PDO (always 5V fixed). As a result, for sources
> which support PPS but whose PPS APDO index does not match with the
> supporting sink PPS APDO index for the platform, no valid PPS APDO
> will be found so this feature will not be permitted.
> 
> Sadly in testing, both Source and Sink capabilities matched up and
> this was missed. Code is now updated to correctly set the start
> index to 1, and testing with additional PPS capable sources show
> this to work as expected.
> 
> Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
> ---
>  drivers/usb/typec/tcpm.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/typec/tcpm.c b/drivers/usb/typec/tcpm.c
> index 74e0cda..4f1f421 100644
> --- a/drivers/usb/typec/tcpm.c
> +++ b/drivers/usb/typec/tcpm.c
> @@ -2238,7 +2238,7 @@ static unsigned int tcpm_pd_select_pps_apdo(struct tcpm_port *port)
>  			 * PPS APDO. Again skip the first sink PDO as this will
>  			 * always be 5V 3A.
>  			 */
> -			for (j = i; j < port->nr_snk_pdo; j++) {
> +			for (j = 1; j < port->nr_snk_pdo; j++) {
>  				pdo = port->snk_pdo[j];
>  
>  				switch (pdo_type(pdo)) {

What commit id does this "fix"?

Does it need to go into 4.18-final?  To the stable kernels?

thanks,

greg k-h

RE: [PATCH] usb: typec: tcpm: Fix sink PDO starting index for PPS APDO selection

[Adam Thomson]

On 20 July 2018 14:59, Greg Kroah-Hartman wrote:

> On Tue, Jul 17, 2018 at 03:36:19PM +0100, Adam Thomson wrote:
> > There is a bug in the sink PDO search code when trying to select
> > a PPS APDO. The current code actually sets the starting index for
> > searching to whatever value 'i' is, rather than choosing index 1
> > to avoid the first PDO (always 5V fixed). As a result, for sources
> > which support PPS but whose PPS APDO index does not match with the
> > supporting sink PPS APDO index for the platform, no valid PPS APDO
> > will be found so this feature will not be permitted.
> >
> > Sadly in testing, both Source and Sink capabilities matched up and
> > this was missed. Code is now updated to correctly set the start
> > index to 1, and testing with additional PPS capable sources show
> > this to work as expected.
> >
> > Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
> > ---
> >  drivers/usb/typec/tcpm.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/usb/typec/tcpm.c b/drivers/usb/typec/tcpm.c
> > index 74e0cda..4f1f421 100644
> > --- a/drivers/usb/typec/tcpm.c
> > +++ b/drivers/usb/typec/tcpm.c
> > @@ -2238,7 +2238,7 @@ static unsigned int tcpm_pd_select_pps_apdo(struct
> tcpm_port *port)
> >  			 * PPS APDO. Again skip the first sink PDO as this will
> >  			 * always be 5V 3A.
> >  			 */
> > -			for (j = i; j < port->nr_snk_pdo; j++) {
> > +			for (j = 1; j < port->nr_snk_pdo; j++) {
> >  				pdo = port->snk_pdo[j];
> >
> >  				switch (pdo_type(pdo)) {
> 
> What commit id does this "fix"?
> 
> Does it need to go into 4.18-final?  To the stable kernels?

Sorry, missed that info. This fixes commit:

2eadc33f40d4c59dd0649f8b6958872d85ad05d7
'typec: tcpm: Add core support for sink side PPS'

This patch only went into v4.18-rc1 so should only be targeted for v4.18-final.

Do you want me to resend with this information added?

Re: [PATCH] usb: typec: tcpm: Fix sink PDO starting index for PPS APDO selection

[Greg Kroah-Hartman]

On Fri, Jul 20, 2018 at 02:16:33PM +0000, Adam Thomson wrote:
> On 20 July 2018 14:59, Greg Kroah-Hartman wrote:
> 
> > On Tue, Jul 17, 2018 at 03:36:19PM +0100, Adam Thomson wrote:
> > > There is a bug in the sink PDO search code when trying to select
> > > a PPS APDO. The current code actually sets the starting index for
> > > searching to whatever value 'i' is, rather than choosing index 1
> > > to avoid the first PDO (always 5V fixed). As a result, for sources
> > > which support PPS but whose PPS APDO index does not match with the
> > > supporting sink PPS APDO index for the platform, no valid PPS APDO
> > > will be found so this feature will not be permitted.
> > >
> > > Sadly in testing, both Source and Sink capabilities matched up and
> > > this was missed. Code is now updated to correctly set the start
> > > index to 1, and testing with additional PPS capable sources show
> > > this to work as expected.
> > >
> > > Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
> > > ---
> > >  drivers/usb/typec/tcpm.c | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/usb/typec/tcpm.c b/drivers/usb/typec/tcpm.c
> > > index 74e0cda..4f1f421 100644
> > > --- a/drivers/usb/typec/tcpm.c
> > > +++ b/drivers/usb/typec/tcpm.c
> > > @@ -2238,7 +2238,7 @@ static unsigned int tcpm_pd_select_pps_apdo(struct
> > tcpm_port *port)
> > >  			 * PPS APDO. Again skip the first sink PDO as this will
> > >  			 * always be 5V 3A.
> > >  			 */
> > > -			for (j = i; j < port->nr_snk_pdo; j++) {
> > > +			for (j = 1; j < port->nr_snk_pdo; j++) {
> > >  				pdo = port->snk_pdo[j];
> > >
> > >  				switch (pdo_type(pdo)) {
> > 
> > What commit id does this "fix"?
> > 
> > Does it need to go into 4.18-final?  To the stable kernels?
> 
> Sorry, missed that info. This fixes commit:
> 
> 2eadc33f40d4c59dd0649f8b6958872d85ad05d7
> 'typec: tcpm: Add core support for sink side PPS'
> 
> This patch only went into v4.18-rc1 so should only be targeted for v4.18-final.
> 
> Do you want me to resend with this information added?

It's ok, this time, I'll go hand-edit it...

greg k-h

RE: [PATCH] usb: typec: tcpm: Fix sink PDO starting index for PPS APDO selection

[Adam Thomson]

On 20 July 2018 15:40, Greg Kroah-Hartman wrote:

> On Fri, Jul 20, 2018 at 02:16:33PM +0000, Adam Thomson wrote:
> > On 20 July 2018 14:59, Greg Kroah-Hartman wrote:
> >
> > > On Tue, Jul 17, 2018 at 03:36:19PM +0100, Adam Thomson wrote:
> > > > There is a bug in the sink PDO search code when trying to select
> > > > a PPS APDO. The current code actually sets the starting index for
> > > > searching to whatever value 'i' is, rather than choosing index 1
> > > > to avoid the first PDO (always 5V fixed). As a result, for sources
> > > > which support PPS but whose PPS APDO index does not match with the
> > > > supporting sink PPS APDO index for the platform, no valid PPS APDO
> > > > will be found so this feature will not be permitted.
> > > >
> > > > Sadly in testing, both Source and Sink capabilities matched up and
> > > > this was missed. Code is now updated to correctly set the start
> > > > index to 1, and testing with additional PPS capable sources show
> > > > this to work as expected.
> > > >
> > > > Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
> > > > ---
> > > >  drivers/usb/typec/tcpm.c | 2 +-
> > > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > > >
> > > > diff --git a/drivers/usb/typec/tcpm.c b/drivers/usb/typec/tcpm.c
> > > > index 74e0cda..4f1f421 100644
> > > > --- a/drivers/usb/typec/tcpm.c
> > > > +++ b/drivers/usb/typec/tcpm.c
> > > > @@ -2238,7 +2238,7 @@ static unsigned int tcpm_pd_select_pps_apdo(struct
> > > tcpm_port *port)
> > > >  			 * PPS APDO. Again skip the first sink PDO as this will
> > > >  			 * always be 5V 3A.
> > > >  			 */
> > > > -			for (j = i; j < port->nr_snk_pdo; j++) {
> > > > +			for (j = 1; j < port->nr_snk_pdo; j++) {
> > > >  				pdo = port->snk_pdo[j];
> > > >
> > > >  				switch (pdo_type(pdo)) {
> > >
> > > What commit id does this "fix"?
> > >
> > > Does it need to go into 4.18-final?  To the stable kernels?
> >
> > Sorry, missed that info. This fixes commit:
> >
> > 2eadc33f40d4c59dd0649f8b6958872d85ad05d7
> > 'typec: tcpm: Add core support for sink side PPS'
> >
> > This patch only went into v4.18-rc1 so should only be targeted for v4.18-final.
> >
> > Do you want me to resend with this information added?
> 
> It's ok, this time, I'll go hand-edit it...

Thanks :)