[PATCH] Make MMCI driver compile without gpiolib

[PATCH] Make MMCI driver compile without gpiolib

[Linus Walleij]

The recent addition of optional gpiolib support to check if a
card was inserted or write protected was really not optional.
It needs this ifdef to become optional so that U300 compiles,
for example.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
---
 drivers/mmc/host/mmci.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 5eb86a8..a923ee2 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -619,6 +619,7 @@ static int __devinit mmci_probe(struct amba_device *dev, struct amba_id *id)
 	writel(0, host->base + MMCIMASK1);
 	writel(0xfff, host->base + MMCICLEAR);
 
+#ifdef CONFIG_GPIOLIB
 	if (gpio_is_valid(plat->gpio_cd)) {
 		ret = gpio_request(plat->gpio_cd, DRIVER_NAME " (cd)");
 		if (ret == 0)
@@ -637,6 +638,7 @@ static int __devinit mmci_probe(struct amba_device *dev, struct amba_id *id)
 		else if (ret != -ENOSYS)
 			goto err_gpio_wp;
 	}
+#endif
 
 	ret = request_irq(dev->irq[0], mmci_irq, IRQF_SHARED, DRIVER_NAME " (cmd)", host);
 	if (ret)
-- 
1.6.2.1

[PATCH] Make MMCI driver compile without gpiolib

[Russell King - ARM Linux]

On Wed, Aug 26, 2009 at 10:56:28AM +0200, Linus Walleij wrote:
> The recent addition of optional gpiolib support to check if a
> card was inserted or write protected was really not optional.
> It needs this ifdef to become optional so that U300 compiles,
> for example.

Looking back at this, I don't think this ifdef is required.

Why?

We're using linux/gpio.h, which provides dummy definitions for the
GPIO functions of GENERIC_GPIO is not set.  If GENERIC_GPIO is set,
then GPIOs are available, and can be used.

GPIOLIB is entirely a different matter, and doesn't really indicate
whether GPIO support is available or not.

The real problem is that U300 doesn't implement gpio_is_valid() -
which is part of the GPIO API and not specific to GPIOLIB.

Please implement this function, and let's revert this (wrong) patch.

> diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
> index 5eb86a8..a923ee2 100644
> --- a/drivers/mmc/host/mmci.c
> +++ b/drivers/mmc/host/mmci.c
> @@ -619,6 +619,7 @@ static int __devinit mmci_probe(struct amba_device *dev, struct amba_id *id)
>  	writel(0, host->base + MMCIMASK1);
>  	writel(0xfff, host->base + MMCICLEAR);
>  
> +#ifdef CONFIG_GPIOLIB
>  	if (gpio_is_valid(plat->gpio_cd)) {
>  		ret = gpio_request(plat->gpio_cd, DRIVER_NAME " (cd)");
>  		if (ret == 0)
> @@ -637,6 +638,7 @@ static int __devinit mmci_probe(struct amba_device *dev, struct amba_id *id)
>  		else if (ret != -ENOSYS)
>  			goto err_gpio_wp;
>  	}
> +#endif
>  
>  	ret = request_irq(dev->irq[0], mmci_irq, IRQF_SHARED, DRIVER_NAME " (cmd)", host);
>  	if (ret)

[PATCH] Make MMCI driver compile without gpiolib

[Linus Walleij]

2009/9/27 Russell King - ARM Linux <linux@arm.linux.org.uk>:

> Looking back at this, I don't think this ifdef is required.

You're righ of course, sorry for that. Fix-up patch just posted,
also in the patch tracker. Reverts these #ifdef:s and fix the root
problem instead.

Linus Walleij

[PATCH] Make MMCI driver compile without gpiolib

[Linus Walleij]

Hm thinking back at this:

2009/9/27 Russell King - ARM Linux <linux@arm.linux.org.uk>:

> The real problem is that U300 doesn't implement gpio_is_valid() -
> which is part of the GPIO API and not specific to GPIOLIB.

None of the GPIO drivers in drivers/gpio implement gpio_is_valid()
though they all select GPIOLIB which in turn selects GENERIC_GPIO.

With one of them being the PL061 this means that the not so
unlikely combination of PL061+PL180 will fail to compile (even
though I'm not aware of such a platform for the time being).

Is it worth taking a run over drivers/gpio and try to fix this or
atleast the PL061 driver? I can have a look at it.

Yours,
Linus Walleij

[PATCH] Make MMCI driver compile without gpiolib

[Baruch Siach]

Hi Linus,

On Mon, Sep 28, 2009 at 09:00:01PM +0200, Linus Walleij wrote:
> Hm thinking back at this:
> 
> 2009/9/27 Russell King - ARM Linux <linux@arm.linux.org.uk>:
> 
> > The real problem is that U300 doesn't implement gpio_is_valid() -
> > which is part of the GPIO API and not specific to GPIOLIB.
> 
> None of the GPIO drivers in drivers/gpio implement gpio_is_valid()
> though they all select GPIOLIB which in turn selects GENERIC_GPIO.
> 
> With one of them being the PL061 this means that the not so
> unlikely combination of PL061+PL180 will fail to compile (even
> though I'm not aware of such a platform for the time being).

Shouldn't gpio_is_valid() be implemented at the platform code? How should the 
generic GPIO driver know the number of valid GPIO lines, or the number of 
PL061 blocks for that matter?

> Is it worth taking a run over drivers/gpio and try to fix this or
> atleast the PL061 driver? I can have a look at it.

baruch

-- 
                                                     ~. .~   Tk Open Systems
=}------------------------------------------------ooO--U--Ooo------------{=
   - baruch at tkos.co.il - tel: +972.2.679.5364, http://www.tkos.co.il -

[PATCH] Make MMCI driver compile without gpiolib

[Russell King - ARM Linux]

On Mon, Sep 28, 2009 at 09:00:01PM +0200, Linus Walleij wrote:
> Hm thinking back at this:
> 
> 2009/9/27 Russell King - ARM Linux <linux@arm.linux.org.uk>:
> 
> > The real problem is that U300 doesn't implement gpio_is_valid() -
> > which is part of the GPIO API and not specific to GPIOLIB.
> 
> None of the GPIO drivers in drivers/gpio implement gpio_is_valid()
> though they all select GPIOLIB which in turn selects GENERIC_GPIO.

include/asm-generic/gpio.h:

#ifdef CONFIG_GPIOLIB
...
/* Platforms may implement their GPIO interface with library code,
 * at a small performance cost for non-inlined operations and some
 * extra memory (for code and for per-GPIO table entries).
 *
 * While the GPIO programming interface defines valid GPIO numbers
 * to be in the range 0..MAX_INT, this library restricts them to the
 * smaller range 0..ARCH_NR_GPIOS-1.
 */

#ifndef ARCH_NR_GPIOS
#define ARCH_NR_GPIOS           256
#endif

static inline int gpio_is_valid(int number)
{
        /* only some non-negative numbers are valid */
        return ((unsigned)number) < ARCH_NR_GPIOS;
}

So, with gpiolib enabled, gpio_is_valid() is predefined assuming that
GPIOs between 0..ARCH_NR_GPIOS are valid.