Re: [PATCH] OMAP3: SDTI: Prevent access to sdti writing if module is not initialized.

[Tony Lindgren <tony@atomide.com>]

* Felipe Balbi <felipe.balbi@nokia.com> [090216 03:50]:
> On Thu, Feb 12, 2009 at 12:39:28PM +0100, Tereshonkov Roman wrote:
> > The function sti_channel_write_trace can be run from process and interrupt
> > context. It has to be completed before other sti_channel_write_trace calls.
> > 
> > Prevent sdti writing when SDTI module is not initialized.

Roman, can you please create a patch against the mainline tree and send
this driver to LKML for integration? I think pretty much the only thing
you should do is get rid of the OMAP_TAG_STI_CONSOLE and use get that
option from kernel command line like all the other consoles do.

Regards,

Tony

> > Signed-off-by: Roman Tereshonkov <roman.tereshonkov@nokia.com>
> 
> Acked-by: Felipe Balbi <felipe.balbi@nokia.com>
> 
> > ---
> >  drivers/misc/sti/sdti.c |   15 ++++++++++++---
> >  1 files changed, 12 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/misc/sti/sdti.c b/drivers/misc/sti/sdti.c
> > index 8c27504..31780de 100644
> > --- a/drivers/misc/sti/sdti.c
> > +++ b/drivers/misc/sti/sdti.c
> > @@ -37,20 +37,25 @@
> >  static struct clk *sdti_fck, *sdti_ick;
> >  void __iomem *sti_base, *sti_channel_base;
> >  static DEFINE_SPINLOCK(sdti_lock);
> > +static int sdti_initialized;
> > 
> >  void sti_channel_write_trace(int len, int id, void *data,
> >                                 unsigned int channel)
> >  {
> >         const u8 *tpntr = data;
> > +       unsigned long flags;
> > 
> > -       spin_lock_irq(&sdti_lock);
> > +       spin_lock_irqsave(&sdti_lock, flags);
> > +
> > +       if (unlikely(!sdti_initialized))
> > +               goto skip;
> > 
> >         sti_channel_writeb(id, channel);
> >         while (len--)
> >                 sti_channel_writeb(*tpntr++, channel);
> >         sti_channel_flush(channel);
> > -
> > -       spin_unlock_irq(&sdti_lock);
> > + skip:
> > +       spin_unlock_irqrestore(&sdti_lock, flags);
> >  }
> >  EXPORT_SYMBOL(sti_channel_write_trace);
> > 
> > @@ -117,6 +122,10 @@ static int __init omap_sdti_init(void)
> >         /* Enable SDTI */
> >         sti_writel((1 << 31) | (i & 0x3FFFFFFF), SDTI_WINCTRL);
> > 
> > +       spin_lock_irq(&sdti_lock);
> > +       sdti_initialized = 1;
> > +       spin_unlock_irq(&sdti_lock);
> > +
> >         i = sti_readl(SDTI_REVISION);
> >         snprintf(buf, sizeof(buf), "OMAP SDTI support loaded (HW v%u.%u)\n",
> >                 (i >> 4) & 0x0f, i & 0x0f);
> > --
> > 1.5.5.1
> > 
> > --
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> 
> -- 
> balbi
> --
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