> From: Hans de Goede <hdegoede@xxxxxxxxxx>
>
> Hi,
>
> On 9/14/23 03:05, Wu, Wentong wrote:
> >> From: Oliver Neukum <oneukum@xxxxxxxx>
> >>
> >> On 13.09.23 03:40, Wentong Wu wrote:
> >>
> >>> +struct ljca_bank_descriptor {
> >>> + u8 bank_id;
> >>> + u8 pin_num;
> >>> +
> >>> + /* 1 bit for each gpio, 1 means valid */
> >>> + u32 valid_pins;
> >>
> >> No endianness?
> >
> > On both sides, the endianness is same.
>
> Right, but normally USB drivers are also written so that they can work on big-
> endian CPUs.
>
> I realize that this driver will likely never be used with a big-endian CPU but still it
> is good practice to make the driver work on big-endian CPUs too. Even if it is just
> to set a good example when other drivers copy the code.
Thanks, I agree the point here.
And I will update the driver after the test, thanks again.
BR,
Wentong
>
>
> So this should be:
>
> struct ljca_bank_descriptor {
> u8 bank_id;
> u8 pin_num;
>
> /* 1 bit for each gpio, 1 means valid */
> __le32 valid_pins;
> } __packed;
>
> And then when reading valid_pins you should use:
>
> u32 valid_pins = get_unaligned_le32(&ljca_bank_descriptor.valid_pins);
>
> On x86_64 the compiler should optimize all of this away to just a regular read.
>
> Regards,
>
> Hans
