Re: [PATCH 2/3] MFD: TWL4030: print warning for out-of-orderscript loading

From: Amit Kucheria
Date: Mon Aug 17 2009 - 07:43:45 EST


On 09 Aug 04, Samuel Ortiz wrote:
> Hi Amit,
>
> On Wed, Jul 08, 2009 at 01:49:35PM +0300, Amit Kucheria wrote:
> > When the sleep script is loaded before the wakeup script, there is a
> > chance that the system might go to sleep before the wakeup script
> > loading is completed. This will lead to a system that does not wakeup
> > and has been observed to cause non-booting boards.
> >
> > Various options were considered to solve this problem, including
> > modification of the core twl4030 power code to be smart enough to
> > reorder the loading of the scripts. But it felt too over-engineered.
> >
> > Hence this patch just warns the DPS script developer so that they may be
> > reordered in the board-code itself.
> >
> > Signed-off-by: Amit Kucheria <amit.kucheria@xxxxxxxxxxxxx>
> > ---
> > drivers/mfd/twl4030-power.c | 11 +++++++++--
> > 1 files changed, 9 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/mfd/twl4030-power.c b/drivers/mfd/twl4030-power.c
> > index bb9e45f..ef4cc4e 100644
> > --- a/drivers/mfd/twl4030-power.c
> > +++ b/drivers/mfd/twl4030-power.c
> > @@ -315,6 +315,7 @@ static int __init load_triton_script(struct twl4030_script *tscript)
> > {
> > u8 address = triton_next_free_address;
> > int err;
> > + static u8 mask = 0;
> >
> > /* Make sure the script isn't going beyond last valid address */
> > if ((address + tscript->size) > (END_OF_SCRIPT-1)) {
> > @@ -331,14 +332,20 @@ static int __init load_triton_script(struct twl4030_script *tscript)
> > if (tscript->flags & TRITON_WRST_SCRIPT)
> > err |= config_warmreset_sequence(address);
> >
> > - if (tscript->flags & TRITON_WAKEUP12_SCRIPT)
> > + if (tscript->flags & TRITON_WAKEUP12_SCRIPT) {
> > err |= config_wakeup12_sequence(address);
> > + mask |= TRITON_WAKEUP12_SCRIPT;
> > + }
> >
> > if (tscript->flags & TRITON_WAKEUP3_SCRIPT)
> > err |= config_wakeup3_sequence(address);
> >
> > - if (tscript->flags & TRITON_SLEEP_SCRIPT)
> > + if (tscript->flags & TRITON_SLEEP_SCRIPT) {
> Wouldnt something like:
>
> if (tscript->flags & (TRITON_SLEEP_SCRIPT | TRITON_WAKEUP12_SCRIPT)) {
>
> save us from using an additional mask variable and simplify this patch ?
>

I don't see how this will save the mask variable. What I need to detect
that the SLEEP script is loaded before the WAKEUP script. That should
trigger a warning.

--
-------------------------------------------------------------------------
Amit Kucheria, Kernel Developer, Verdurent
-------------------------------------------------------------------------
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/