[PATCH v2] usb:typec:tcpm:support double Rp to Vbus cable as sink

[PATCH v2] usb:typec:tcpm:support double Rp to Vbus cable as sink

[Michael Wu]

The USB Type-C Cable and Connector Specification defines the wire
connections for the USB Type-C to USB 2.0 Standard-A cable assembly
(Release 2.2, Chapter 3.5.2).
The Notes says that Pin A5 (CC) of the USB Type-C plug shall be connected
to Vbus through a resister Rp.
However, there is a large amount of such double Rp connected to Vbus
non-standard cables which produced by UGREEN circulating on the market, and
it can affects the normal operations of the state machine easily,
especially to CC1 and CC2 be pulled up at the same time.
In fact, we can regard those cables as sink to avoid abnormal state.

Message as follow:
[   58.900212] VBUS on
[   59.265433] CC1: 0 -> 3, CC2: 0 -> 3 [state TOGGLING, polarity 0, connected]
[   62.623308] CC1: 3 -> 0, CC2: 3 -> 0 [state TOGGLING, polarity 0, disconnected]
[   62.625006] VBUS off
[   62.625012] VBUS VSAFE0V

Signed-off-by: Michael Wu <michael@allwinnertech.com>
---
 drivers/usb/typec/tcpm/tcpm.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index d962f67c95ae6..6e843c511b856 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -517,9 +517,9 @@ static const char * const pd_rev[] = {
 	((cc) == TYPEC_CC_RP_DEF || (cc) == TYPEC_CC_RP_1_5 || \
 	 (cc) == TYPEC_CC_RP_3_0)
 
+/* As long as cc is pulled up, we can consider it as sink. */
 #define tcpm_port_is_sink(port) \
-	((tcpm_cc_is_sink((port)->cc1) && !tcpm_cc_is_sink((port)->cc2)) || \
-	 (tcpm_cc_is_sink((port)->cc2) && !tcpm_cc_is_sink((port)->cc1)))
+	(tcpm_cc_is_sink((port)->cc1) || tcpm_cc_is_sink((port)->cc2))
 
 #define tcpm_cc_is_source(cc) ((cc) == TYPEC_CC_RD)
 #define tcpm_cc_is_audio(cc) ((cc) == TYPEC_CC_RA)
-- 
2.29.0

Re: [PATCH v2] usb:typec:tcpm:support double Rp to Vbus cable as sink

[Greg KH]

On Tue, Sep 19, 2023 at 05:06:32PM +0800, Michael Wu wrote:
> The USB Type-C Cable and Connector Specification defines the wire
> connections for the USB Type-C to USB 2.0 Standard-A cable assembly
> (Release 2.2, Chapter 3.5.2).
> The Notes says that Pin A5 (CC) of the USB Type-C plug shall be connected
> to Vbus through a resister Rp.
> However, there is a large amount of such double Rp connected to Vbus
> non-standard cables which produced by UGREEN circulating on the market, and
> it can affects the normal operations of the state machine easily,
> especially to CC1 and CC2 be pulled up at the same time.
> In fact, we can regard those cables as sink to avoid abnormal state.
> 
> Message as follow:
> [   58.900212] VBUS on
> [   59.265433] CC1: 0 -> 3, CC2: 0 -> 3 [state TOGGLING, polarity 0, connected]
> [   62.623308] CC1: 3 -> 0, CC2: 3 -> 0 [state TOGGLING, polarity 0, disconnected]
> [   62.625006] VBUS off
> [   62.625012] VBUS VSAFE0V
> 
> Signed-off-by: Michael Wu <michael@allwinnertech.com>
> ---
>  drivers/usb/typec/tcpm/tcpm.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index d962f67c95ae6..6e843c511b856 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -517,9 +517,9 @@ static const char * const pd_rev[] = {
>  	((cc) == TYPEC_CC_RP_DEF || (cc) == TYPEC_CC_RP_1_5 || \
>  	 (cc) == TYPEC_CC_RP_3_0)
>  
> +/* As long as cc is pulled up, we can consider it as sink. */
>  #define tcpm_port_is_sink(port) \
> -	((tcpm_cc_is_sink((port)->cc1) && !tcpm_cc_is_sink((port)->cc2)) || \
> -	 (tcpm_cc_is_sink((port)->cc2) && !tcpm_cc_is_sink((port)->cc1)))
> +	(tcpm_cc_is_sink((port)->cc1) || tcpm_cc_is_sink((port)->cc2))
>  
>  #define tcpm_cc_is_source(cc) ((cc) == TYPEC_CC_RD)
>  #define tcpm_cc_is_audio(cc) ((cc) == TYPEC_CC_RA)
> -- 
> 2.29.0
> 
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
as indicated below:

- This looks like a new version of a previously submitted patch, but you
  did not list below the --- line any changes from the previous version.
  Please read the section entitled "The canonical patch format" in the
  kernel file, Documentation/process/submitting-patches.rst for what
  needs to be done here to properly describe this.

If you wish to discuss this problem further, or you have questions about
how to resolve this issue, please feel free to respond to this email and
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thanks,

greg k-h's patch email bot