diff mbox series

[v2,2/2] usb: usb251xb: add usb data lane port swap feature

Message ID 20190115115018.27143-2-m.felsch@pengutronix.de (mailing list archive)
State New, archived
Headers show
Series [v2,1/2] dt-bindings: usb: usb251xb: add documentation for data lane swapping | expand

Commit Message

Marco Felsch Jan. 15, 2019, 11:50 a.m. UTC 
The HW can swap the USB differential-pair (D+/D-) for each port
separately. So the USB signals can be re-aligned with a misplaced
USB connector on the PCB.

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
---
Changes:
v2:
 - rename property s/sw-dx-lanes-ports/swap-dx-lanes
 - add commentar for future users

 drivers/usb/misc/usb251xb.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

Comments

Marco Felsch Jan. 15, 2019, 12:04 p.m. UTC | #1 
Hi,

On 19-01-15 12:50, Marco Felsch wrote:
> The HW can swap the USB differential-pair (D+/D-) for each port
> separately. So the USB signals can be re-aligned with a misplaced
> USB connector on the PCB.
> 
> Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
> ---
> Changes:
> v2:
>  - rename property s/sw-dx-lanes-ports/swap-dx-lanes
>  - add commentar for future users
> 
>  drivers/usb/misc/usb251xb.c | 15 +++++++++++++--
>  1 file changed, 13 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/misc/usb251xb.c b/drivers/usb/misc/usb251xb.c
> index a6efb9a72939..ec649046688d 100644
> --- a/drivers/usb/misc/usb251xb.c
> +++ b/drivers/usb/misc/usb251xb.c
> @@ -337,10 +337,12 @@ static int usb251xb_get_ofdata(struct usb251xb *hub,
>  	struct device *dev = hub->dev;
>  	struct device_node *np = dev->of_node;
>  	int len, err, i;
> -	u32 property_u32 = 0;
> +	u32 port, property_u32 = 0;
>  	const u32 *cproperty_u32;
>  	const char *cproperty_char;
>  	char str[USB251XB_STRING_BUFSIZE / 2];
> +	struct property *prop;
> +	const __be32 *p;
>  
>  	if (!np) {
>  		dev_err(dev, "failed to get ofdata\n");
> @@ -539,6 +541,16 @@ static int usb251xb_get_ofdata(struct usb251xb *hub,
>  			      (wchar_t *)hub->serial,
>  			      USB251XB_STRING_BUFSIZE);
> 
> +	/*
> +	 * The datasheet documents the register as 'Port Swap' but the register
> +	 * controls the USB DP/DM signal swapping
> +	 */

Sorry for the noise, unfortunately I forgot to update the patch..
Richard can you fix the commentar inline to:

8<----------------------------------------------------------------------------
+       /*
+        * The datasheet documents the register as 'Port Swap' but in real the
+        * register controls the USB DP/DM signal swapping for each port.
+        */
8<----------------------------------------------------------------------------

> +	hub->port_swap = USB251XB_DEF_PORT_SWAP;
> +	of_property_for_each_u32(np, "swap-dx-lanes", prop, p, port) {
> +		if ((port >= 0) && (port <= data->port_cnt))
> +			hub->port_swap |= BIT(port);
> +	}
> +
>  	/* The following parameters are currently not exposed to devicetree, but
>  	 * may be as soon as needed.
>  	 */
> @@ -546,7 +558,6 @@ static int usb251xb_get_ofdata(struct usb251xb *hub,
>  	hub->boost_up = USB251XB_DEF_BOOST_UP;
>  	hub->boost_57 = USB251XB_DEF_BOOST_57;
>  	hub->boost_14 = USB251XB_DEF_BOOST_14;
> -	hub->port_swap = USB251XB_DEF_PORT_SWAP;
>  	hub->port_map12 = USB251XB_DEF_PORT_MAP_12;
>  	hub->port_map34 = USB251XB_DEF_PORT_MAP_34;
>  	hub->port_map56 = USB251XB_DEF_PORT_MAP_56;
> -- 
> 2.20.1
> 
> 
>
Richard Leitner Jan. 16, 2019, 1:56 p.m. UTC | #2 
Hi,

On 15/01/2019 13:04, Marco Felsch wrote:
> Hi,
> 
> On 19-01-15 12:50, Marco Felsch wrote:
>> The HW can swap the USB differential-pair (D+/D-) for each port
>> separately. So the USB signals can be re-aligned with a misplaced
>> USB connector on the PCB.
>>
>> Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
>> ---
>> Changes:
>> v2:
>>   - rename property s/sw-dx-lanes-ports/swap-dx-lanes
>>   - add commentar for future users
>>
>>   drivers/usb/misc/usb251xb.c | 15 +++++++++++++--
>>   1 file changed, 13 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/usb/misc/usb251xb.c b/drivers/usb/misc/usb251xb.c
>> index a6efb9a72939..ec649046688d 100644
>> --- a/drivers/usb/misc/usb251xb.c
>> +++ b/drivers/usb/misc/usb251xb.c
>> @@ -337,10 +337,12 @@ static int usb251xb_get_ofdata(struct usb251xb *hub,
>>   	struct device *dev = hub->dev;
>>   	struct device_node *np = dev->of_node;
>>   	int len, err, i;
>> -	u32 property_u32 = 0;
>> +	u32 port, property_u32 = 0;
>>   	const u32 *cproperty_u32;
>>   	const char *cproperty_char;
>>   	char str[USB251XB_STRING_BUFSIZE / 2];
>> +	struct property *prop;
>> +	const __be32 *p;
>>   
>>   	if (!np) {
>>   		dev_err(dev, "failed to get ofdata\n");
>> @@ -539,6 +541,16 @@ static int usb251xb_get_ofdata(struct usb251xb *hub,
>>   			      (wchar_t *)hub->serial,
>>   			      USB251XB_STRING_BUFSIZE);
>>
>> +	/*
>> +	 * The datasheet documents the register as 'Port Swap' but the register
>> +	 * controls the USB DP/DM signal swapping
>> +	 */
> 
> Sorry for the noise, unfortunately I forgot to update the patch..
> Richard can you fix the commentar inline to:
> 
> 8<----------------------------------------------------------------------------
> +       /*
> +        * The datasheet documents the register as 'Port Swap' but in real the
> +        * register controls the USB DP/DM signal swapping for each port.
> +        */
> 8<----------------------------------------------------------------------------

With this applied the patch looks good to me, therefore feel free to add:

Reviewed-by: Richard Leitner <richard.leitner@skidata.com>

Furthermore please send a v3 with this fixed and put Greg-KH 
(gregkh@linuxfoundation.org) on CC as he will merge it into his tree.

regards;Richard.L
diff mbox series

Patch

diff --git a/drivers/usb/misc/usb251xb.c b/drivers/usb/misc/usb251xb.c
index a6efb9a72939..ec649046688d 100644
--- a/drivers/usb/misc/usb251xb.c
+++ b/drivers/usb/misc/usb251xb.c
@@ -337,10 +337,12 @@  static int usb251xb_get_ofdata(struct usb251xb *hub,
 	struct device *dev = hub->dev;
 	struct device_node *np = dev->of_node;
 	int len, err, i;
-	u32 property_u32 = 0;
+	u32 port, property_u32 = 0;
 	const u32 *cproperty_u32;
 	const char *cproperty_char;
 	char str[USB251XB_STRING_BUFSIZE / 2];
+	struct property *prop;
+	const __be32 *p;
 
 	if (!np) {
 		dev_err(dev, "failed to get ofdata\n");
@@ -539,6 +541,16 @@  static int usb251xb_get_ofdata(struct usb251xb *hub,
 			      (wchar_t *)hub->serial,
 			      USB251XB_STRING_BUFSIZE);
 
+	/*
+	 * The datasheet documents the register as 'Port Swap' but the register
+	 * controls the USB DP/DM signal swapping
+	 */
+	hub->port_swap = USB251XB_DEF_PORT_SWAP;
+	of_property_for_each_u32(np, "swap-dx-lanes", prop, p, port) {
+		if ((port >= 0) && (port <= data->port_cnt))
+			hub->port_swap |= BIT(port);
+	}
+
 	/* The following parameters are currently not exposed to devicetree, but
 	 * may be as soon as needed.
 	 */
@@ -546,7 +558,6 @@  static int usb251xb_get_ofdata(struct usb251xb *hub,
 	hub->boost_up = USB251XB_DEF_BOOST_UP;
 	hub->boost_57 = USB251XB_DEF_BOOST_57;
 	hub->boost_14 = USB251XB_DEF_BOOST_14;
-	hub->port_swap = USB251XB_DEF_PORT_SWAP;
 	hub->port_map12 = USB251XB_DEF_PORT_MAP_12;
 	hub->port_map34 = USB251XB_DEF_PORT_MAP_34;
 	hub->port_map56 = USB251XB_DEF_PORT_MAP_56;