Re: [PATCH v6] usb: core: Add "quirks" parameter for usbcore

[Kai Heng Feng]

Kai Heng Feng  wrote:


Matthew Wilcox  wrote:


On Tue, Mar 13, 2018 at 03:26:19PM +0800, Kai-Heng Feng wrote:

+   usbcore.quirks=
+   [USB] A list of quirks entries to supplement or
+   override the built-in usb core quirk list.  List
+   entries are separated by commas.  Each entry has
+   the form VID:PID:Flags where VID and PID are Vendor
+   and Product ID values (4-digit hex numbers) and
+   Flags is a set of characters, each corresponding
+   to a common usb core quirk flag as follows:


This doesn't really tell me that the specified quirks will be XORed with
the built-in quirks.  Maybe something like ...

[USB] A list of quirk entries to augment the
built-in usb core quirk list.  List entries are
separated by commas.  Each entry has the form
VendorID:ProductID:Flags.  The IDs are 4-digit hex
numbers and Flags is a set of letters.  Each letter
will change the built-in quirk; setting it if it is
clear and clearing it if it is set.  The letters
have the following meanings:


Thanks, will update the description to specify the XOR behavior.


+   /* Each entry consists of VID:PID:flags */
+   field = strsep(, ":");
+   if (!field)
+   break;
+
+   if (kstrtou16(field, 16, ))
+   break;
+
+   field = strsep(, ":");
+   if (!field)
+   break;
+
+   if (kstrtou16(field, 16, ))
+   break;


Is there a reason to not use sscanf here like hid-quirks.c does?


Actually I use sscanf in previous patch version. Using kstrto* isn't  
needed anymore, I'll use sscanf in next version.


Okay, I remember why I don't use sscanf, mainly because the quirk_param in  
hid-quirks.c is charp instead of char, so using sscanf is trivia for it.


We use plain char* here because of module_param_cb(), so I guess using  
sscanf doesn't make much sense here. strsep() isn't the most elegant  
solution but it does its job well.


I'll update the description and send a new patch.

Kai-Heng



Kai-Heng

Re: [PATCH v6] usb: core: Add "quirks" parameter for usbcore

[Kai Heng Feng]

Kai Heng Feng  wrote:


Matthew Wilcox  wrote:


On Tue, Mar 13, 2018 at 03:26:19PM +0800, Kai-Heng Feng wrote:

+   usbcore.quirks=
+   [USB] A list of quirks entries to supplement or
+   override the built-in usb core quirk list.  List
+   entries are separated by commas.  Each entry has
+   the form VID:PID:Flags where VID and PID are Vendor
+   and Product ID values (4-digit hex numbers) and
+   Flags is a set of characters, each corresponding
+   to a common usb core quirk flag as follows:


This doesn't really tell me that the specified quirks will be XORed with
the built-in quirks.  Maybe something like ...

[USB] A list of quirk entries to augment the
built-in usb core quirk list.  List entries are
separated by commas.  Each entry has the form
VendorID:ProductID:Flags.  The IDs are 4-digit hex
numbers and Flags is a set of letters.  Each letter
will change the built-in quirk; setting it if it is
clear and clearing it if it is set.  The letters
have the following meanings:


Thanks, will update the description to specify the XOR behavior.


+   /* Each entry consists of VID:PID:flags */
+   field = strsep(, ":");
+   if (!field)
+   break;
+
+   if (kstrtou16(field, 16, ))
+   break;
+
+   field = strsep(, ":");
+   if (!field)
+   break;
+
+   if (kstrtou16(field, 16, ))
+   break;


Is there a reason to not use sscanf here like hid-quirks.c does?


Actually I use sscanf in previous patch version. Using kstrto* isn't  
needed anymore, I'll use sscanf in next version.


Okay, I remember why I don't use sscanf, mainly because the quirk_param in  
hid-quirks.c is charp instead of char, so using sscanf is trivia for it.


We use plain char* here because of module_param_cb(), so I guess using  
sscanf doesn't make much sense here. strsep() isn't the most elegant  
solution but it does its job well.


I'll update the description and send a new patch.

Kai-Heng



Kai-Heng

Re: [PATCH v6] usb: core: Add "quirks" parameter for usbcore

[Kai Heng Feng]

Matthew Wilcox  wrote:


On Tue, Mar 13, 2018 at 03:26:19PM +0800, Kai-Heng Feng wrote:

+   usbcore.quirks=
+   [USB] A list of quirks entries to supplement or
+   override the built-in usb core quirk list.  List
+   entries are separated by commas.  Each entry has
+   the form VID:PID:Flags where VID and PID are Vendor
+   and Product ID values (4-digit hex numbers) and
+   Flags is a set of characters, each corresponding
+   to a common usb core quirk flag as follows:


This doesn't really tell me that the specified quirks will be XORed with
the built-in quirks.  Maybe something like ...

[USB] A list of quirk entries to augment the
built-in usb core quirk list.  List entries are
separated by commas.  Each entry has the form
VendorID:ProductID:Flags.  The IDs are 4-digit hex
numbers and Flags is a set of letters.  Each letter
will change the built-in quirk; setting it if it is
clear and clearing it if it is set.  The letters
have the following meanings:


Thanks, will update the description to specify the XOR behavior.




+   /* Each entry consists of VID:PID:flags */
+   field = strsep(, ":");
+   if (!field)
+   break;
+
+   if (kstrtou16(field, 16, ))
+   break;
+
+   field = strsep(, ":");
+   if (!field)
+   break;
+
+   if (kstrtou16(field, 16, ))
+   break;


Is there a reason to not use sscanf here like hid-quirks.c does?


Actually I use sscanf in previous patch version. Using kstrto* isn't needed  
anymore, I'll use sscanf in next version.


Kai-Heng

Re: [PATCH v6] usb: core: Add "quirks" parameter for usbcore

[Kai Heng Feng]

Matthew Wilcox  wrote:


On Tue, Mar 13, 2018 at 03:26:19PM +0800, Kai-Heng Feng wrote:

+   usbcore.quirks=
+   [USB] A list of quirks entries to supplement or
+   override the built-in usb core quirk list.  List
+   entries are separated by commas.  Each entry has
+   the form VID:PID:Flags where VID and PID are Vendor
+   and Product ID values (4-digit hex numbers) and
+   Flags is a set of characters, each corresponding
+   to a common usb core quirk flag as follows:


This doesn't really tell me that the specified quirks will be XORed with
the built-in quirks.  Maybe something like ...

[USB] A list of quirk entries to augment the
built-in usb core quirk list.  List entries are
separated by commas.  Each entry has the form
VendorID:ProductID:Flags.  The IDs are 4-digit hex
numbers and Flags is a set of letters.  Each letter
will change the built-in quirk; setting it if it is
clear and clearing it if it is set.  The letters
have the following meanings:


Thanks, will update the description to specify the XOR behavior.




+   /* Each entry consists of VID:PID:flags */
+   field = strsep(, ":");
+   if (!field)
+   break;
+
+   if (kstrtou16(field, 16, ))
+   break;
+
+   field = strsep(, ":");
+   if (!field)
+   break;
+
+   if (kstrtou16(field, 16, ))
+   break;


Is there a reason to not use sscanf here like hid-quirks.c does?


Actually I use sscanf in previous patch version. Using kstrto* isn't needed  
anymore, I'll use sscanf in next version.


Kai-Heng

Re: [PATCH v6] usb: core: Add "quirks" parameter for usbcore

[Matthew Wilcox]

On Tue, Mar 13, 2018 at 03:26:19PM +0800, Kai-Heng Feng wrote:
> + usbcore.quirks=
> + [USB] A list of quirks entries to supplement or
> + override the built-in usb core quirk list.  List
> + entries are separated by commas.  Each entry has
> + the form VID:PID:Flags where VID and PID are Vendor
> + and Product ID values (4-digit hex numbers) and
> + Flags is a set of characters, each corresponding
> + to a common usb core quirk flag as follows:

This doesn't really tell me that the specified quirks will be XORed with
the built-in quirks.  Maybe something like ...

[USB] A list of quirk entries to augment the
built-in usb core quirk list.  List entries are
separated by commas.  Each entry has the form
VendorID:ProductID:Flags.  The IDs are 4-digit hex
numbers and Flags is a set of letters.  Each letter
will change the built-in quirk; setting it if it is
clear and clearing it if it is set.  The letters
have the following meanings:

> + /* Each entry consists of VID:PID:flags */
> + field = strsep(, ":");
> + if (!field)
> + break;
> +
> + if (kstrtou16(field, 16, ))
> + break;
> +
> + field = strsep(, ":");
> + if (!field)
> + break;
> +
> + if (kstrtou16(field, 16, ))
> + break;

Is there a reason to not use sscanf here like hid-quirks.c does? 

Re: [PATCH v6] usb: core: Add "quirks" parameter for usbcore

[Matthew Wilcox]

On Tue, Mar 13, 2018 at 03:26:19PM +0800, Kai-Heng Feng wrote:
> + usbcore.quirks=
> + [USB] A list of quirks entries to supplement or
> + override the built-in usb core quirk list.  List
> + entries are separated by commas.  Each entry has
> + the form VID:PID:Flags where VID and PID are Vendor
> + and Product ID values (4-digit hex numbers) and
> + Flags is a set of characters, each corresponding
> + to a common usb core quirk flag as follows:

This doesn't really tell me that the specified quirks will be XORed with
the built-in quirks.  Maybe something like ...

[USB] A list of quirk entries to augment the
built-in usb core quirk list.  List entries are
separated by commas.  Each entry has the form
VendorID:ProductID:Flags.  The IDs are 4-digit hex
numbers and Flags is a set of letters.  Each letter
will change the built-in quirk; setting it if it is
clear and clearing it if it is set.  The letters
have the following meanings:

> + /* Each entry consists of VID:PID:flags */
> + field = strsep(, ":");
> + if (!field)
> + break;
> +
> + if (kstrtou16(field, 16, ))
> + break;
> +
> + field = strsep(, ":");
> + if (!field)
> + break;
> +
> + if (kstrtou16(field, 16, ))
> + break;

Is there a reason to not use sscanf here like hid-quirks.c does?