Re: [PATCH 2.6.19-rc1 update4] drivers: add LCD support

[Miguel Ojeda]

On 10/27/06, Andrew Morton <akpm@xxxxxxxx> wrote:
> On Thu, 26 Oct 2006 17:48:58 +0000
> Miguel Ojeda Sandonis <maxextreme@xxxxxxxxx> wrote:
>
> >
> > +DECLARE_MUTEX(cfag12864bfb_sem);
>
> Mutexes are preferred - please only use semaphores if their counting
> feature is required.
>
> This lock can have static scope.
>
> > +struct page *cfag12864bfb_vma_nopage(struct vm_area_struct *vma,
> > +     unsigned long address, int *type)
>
> This function can have static scope.
>
> > +{
> > +     struct page *page;
> > +     down(&cfag12864bfb_sem);
> > +
> > +     page = virt_to_page(cfag12864b_buffer);
> > +     get_page(page);
> > +
> > +     if(type)
> > +             *type = VM_FAULT_MINOR;
> > +
> > +     up(&cfag12864bfb_sem);
> > +     return page;
> > +}
>
> What's the semaphore actually needed for?

Hum, the code is based on LDD3, I just adapted it removing a few
lines. I thought this code also needed lock protection as the LDD3
example. I'm sending a new patch in a few moments with this 3 things
fixed.

Thanks you,
    Miguel Ojeda
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