[BISECTED] 3.10-rc1 OMAP1 GPIO IRQ regression

[Grant Likely]

On Mon, 20 May 2013 10:46:21 -0700, Tony Lindgren <tony at atomide.com> wrote:
> * Tony Lindgren <tony at atomide.com> [130516 14:50]:
> > * Aaro Koskinen <aaro.koskinen at iki.fi> [130516 14:05]:
> > > On Thu, May 16, 2013 at 11:09:34AM -0700, Tony Lindgren wrote:
> > > > * Aaro Koskinen <aaro.koskinen at iki.fi> [130513 13:58]:
> > > > > I tested 3.10-rc1 on OMAP1 / Nokia 770, and Retu MFD probe is broken:
> > > > > 
> > > > > [    2.264221] retu-mfd 2-0001: Retu v3.2 found
> > > > > [    2.281951] retu-mfd 2-0001: Failed to allocate IRQs: -12
> > > > > [    2.300140] retu-mfd: probe of 2-0001 failed with error -12
> > > > > 
> > > > > The error is coming from regmap code. According to git bisect, it is
> > > > > caused by:
> > > > > 
> > > > > 	commit ede4d7a5b9835510fd1f724367f68d2fa4128453
> > > > > 	Author: Jon Hunter <jon-hunter at ti.com>
> > > > > 	Date:   Fri Mar 1 11:22:47 2013 -0600
> > > > > 
> > > > > 	    gpio/omap: convert gpio irq domain to linear mapping
> > > > > 
> > > > > The commit does not anymore revert cleanly, and I haven't yet tried
> > > > > crafting a manual revert, so any fix proposals/ideas are welcome...
> > > > 
> > > > Hmm this might be a bit trickier to fix. Obviously the real solution
> > > > is to convert omap1 to SPARSE_IRQ like we did for omap2+.
> > > > 
> > > > For the -rc cycle, it might be possible to fix this by adding a
> > > > different irq_to_gpio() and gpio_to_irq() functions for omap1.
> > > 
> > > The commit reverts cleanly if we also revert
> > > 3513cdeccc647d41c4a9ff923af17deaaac04a66 (gpio/omap: optimise interrupt
> > > service routine), which seems to be just some minor optimization. The
> > > result is below, and with it 770 works again.
> > 
> > Hmm in this case it seems that we should just fix it rather than go back
> > to the old code, so let's take a look at that first.
> 
> Does the following fix it for you or do we need to fix something else
> there too?
> 

Hi Tony,

Do you want me to apply this fix? It sounds like it solves the symptoms,
but I'd like to know more about what the root cause is.

Send me your s-o-b line and I'll apply the patch

g.

> 
> 
> --- a/drivers/gpio/gpio-omap.c
> +++ b/drivers/gpio/gpio-omap.c
> @@ -1094,6 +1094,7 @@ static int omap_gpio_probe(struct platform_device *pdev)
>  	const struct omap_gpio_platform_data *pdata;
>  	struct resource *res;
>  	struct gpio_bank *bank;
> +	int irq_base;
>  
>  	match = of_match_device(of_match_ptr(omap_gpio_match), dev);
>  
> @@ -1135,11 +1136,23 @@ static int omap_gpio_probe(struct platform_device *pdev)
>  				pdata->get_context_loss_count;
>  	}
>  
> -
> -	bank->domain = irq_domain_add_linear(node, bank->width,
> -					     &irq_domain_simple_ops, NULL);
> -	if (!bank->domain)
> +	/*
> +	 * REVISIT: Once we have omap1 supporting  SPARSE_IRQ, we can drop
> +	 * irq_alloc_descs() and irq_domain_add_legacy() and just do:
> +	 *
> +	 * bank->domain = irq_domain_add_linear(node, bank->width,
> +	 *				     &irq_domain_simple_ops, NULL);
> +	 * if (!bank->domain)
> +	 *	return -ENODEV;
> +	 */
> +	irq_base = irq_alloc_descs(-1, 0, bank->width, 0);
> +	if (irq_base < 0) {
> +		dev_err(dev, "Couldn't allocate IRQ numbers\n");
>  		return -ENODEV;
> +	}
> +
> +	bank->domain = irq_domain_add_legacy(node, bank->width, irq_base,
> +					     0, &irq_domain_simple_ops, NULL);
>  
>  	if (bank->regs->set_dataout && bank->regs->clr_dataout)
>  		bank->set_dataout = _set_gpio_dataout_reg;

-- 
Grant Likely, B.Sc, P.Eng.
Secret Lab Technologies, Ltd.