Re: [PATCH RESEND] libertas_spi: Add support for suspend/resume

[Marek Vasut <marek.vasut@gmail.com>]

On Thursday 17 March 2011 17:44:27 Dan Williams wrote:
> On Wed, 2011-03-16 at 16:41 +0200, Vasily Khoruzhick wrote:
> > Add support for suspend/resume in if_spi.
> > 
> > Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
> 
> Unless Marek chimes in, I don't have a problem with this patch if it
> fixes the problem.  The one issue I can see is that if userspace isn't
> ready yet, the request_firmware() call will fail because we're not
> caching firmware anywhere, and we probably shouldn't be since the
> firmware is large.  I'm not sure there's a good solution without caching
> firmware though, but I don't want that to block the patch...

Maybe we should implement in-kernel FW cache for this kind of situations. Such 
feature could be configurable too ?

Cheers
> 
> Acked-by: Dan Williams <dcbw@redhat.com>
> 
> > ---
> > 
> >  drivers/net/wireless/libertas/if_spi.c |   65
> >  ++++++++++++++++++++++++++++++++ 1 files changed, 65 insertions(+), 0
> >  deletions(-)
> > 
> > diff --git a/drivers/net/wireless/libertas/if_spi.c
> > b/drivers/net/wireless/libertas/if_spi.c index f6c2cd6..078ef43 100644
> > --- a/drivers/net/wireless/libertas/if_spi.c
> > +++ b/drivers/net/wireless/libertas/if_spi.c
> > @@ -57,6 +57,7 @@ struct if_spi_card {
> > 
> >  	/* Handles all SPI communication (except for FW load) */
> >  	struct workqueue_struct		*workqueue;
> >  	struct work_struct		packet_work;
> > 
> > +	struct work_struct		resume_work;
> > 
> >  	u8				cmd_buffer[IF_SPI_CMD_BUF_SIZE];
> > 
> > @@ -68,6 +69,9 @@ struct if_spi_card {
> > 
> >  	/* Protects cmd_packet_list and data_packet_list */
> >  	spinlock_t			buffer_lock;
> > 
> > +
> > +	/* True is card suspended */
> > +	u8				suspended;
> > 
> >  };
> >  
> >  static void free_if_spi_card(struct if_spi_card *card)
> > 
> > @@ -1057,6 +1061,28 @@ out:
> >  	return err;
> >  
> >  }
> > 
> > +static void if_spi_resume_worker(struct work_struct *work)
> > +{
> > +	struct if_spi_card *card;
> > +
> > +	card = container_of(work, struct if_spi_card, resume_work);
> > +
> > +	if (card->suspended) {
> > +		if (card->pdata->setup)
> > +			card->pdata->setup(card->spi);
> > +
> > +		/* Init card ... */
> > +		if_spi_init_card(card);
> > +
> > +		enable_irq(card->spi->irq);
> > +
> > +		/* And resume it ... */
> > +		lbs_resume(card->priv);
> > +
> > +		card->suspended = 0;
> > +	}
> > +}
> > +
> > 
> >  static int __devinit if_spi_probe(struct spi_device *spi)
> >  {
> >  
> >  	struct if_spi_card *card;
> > 
> > @@ -1107,6 +1133,7 @@ static int __devinit if_spi_probe(struct spi_device
> > *spi)
> > 
> >  		goto free_card;
> >  	
> >  	}
> >  	card->priv = priv;
> > 
> > +	priv->setup_fw_on_resume = 1;
> > 
> >  	priv->card = card;
> >  	priv->hw_host_to_card = if_spi_host_to_card;
> >  	priv->enter_deep_sleep = NULL;
> > 
> > @@ -1117,6 +1144,7 @@ static int __devinit if_spi_probe(struct spi_device
> > *spi)
> > 
> >  	/* Initialize interrupt handling stuff. */
> >  	card->workqueue = create_workqueue("libertas_spi");
> >  	INIT_WORK(&card->packet_work, if_spi_host_to_card_worker);
> > 
> > +	INIT_WORK(&card->resume_work, if_spi_resume_worker);
> > 
> >  	err = request_irq(spi->irq, if_spi_host_interrupt,
> >  	
> >  			IRQF_TRIGGER_FALLING, "libertas_spi", card);
> > 
> > @@ -1161,6 +1189,8 @@ static int __devexit libertas_spi_remove(struct
> > spi_device *spi)
> > 
> >  	lbs_deb_spi("libertas_spi_remove\n");
> >  	lbs_deb_enter(LBS_DEB_SPI);
> > 
> > +	cancel_work_sync(&card->resume_work);
> > +
> > 
> >  	lbs_stop_card(priv);
> >  	lbs_remove_card(priv); /* will call free_netdev */
> > 
> > @@ -1174,6 +1204,40 @@ static int __devexit libertas_spi_remove(struct
> > spi_device *spi)
> > 
> >  	return 0;
> >  
> >  }
> > 
> > +static int if_spi_suspend(struct device *dev)
> > +{
> > +	struct spi_device *spi = to_spi_device(dev);
> > +	struct if_spi_card *card = spi_get_drvdata(spi);
> > +
> > +	if (!card->suspended) {
> > +		lbs_suspend(card->priv);
> > +		flush_workqueue(card->workqueue);
> > +		disable_irq(spi->irq);
> > +
> > +		if (card->pdata->teardown)
> > +			card->pdata->teardown(spi);
> > +		card->suspended = 1;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static int if_spi_resume(struct device *dev)
> > +{
> > +	struct spi_device *spi = to_spi_device(dev);
> > +	struct if_spi_card *card = spi_get_drvdata(spi);
> > +
> > +	/* Schedule delayed work */
> > +	schedule_work(&card->resume_work);
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct dev_pm_ops if_spi_pm_ops = {
> > +	.suspend	= if_spi_suspend,
> > +	.resume		= if_spi_resume,
> > +};
> > +
> > 
> >  static struct spi_driver libertas_spi_driver = {
> >  
> >  	.probe	= if_spi_probe,
> >  	.remove = __devexit_p(libertas_spi_remove),
> > 
> > @@ -1181,6 +1245,7 @@ static struct spi_driver libertas_spi_driver = {
> > 
> >  		.name	= "libertas_spi",
> >  		.bus	= &spi_bus_type,
> >  		.owner	= THIS_MODULE,
> > 
> > +		.pm	= &if_spi_pm_ops,
> > 
> >  	},
> >  
> >  };