irq_to_gpio support

[arnd@arndb.de (Arnd Bergmann)]

On Thursday 19 April 2012, Richard Zhao wrote:
> Hi Grant & Linus
> 
> I saw gpio lib didn't provide irq_to_gpio support. Are we dropping it?
> git grep irq_to_gpio still return a lot of things.

There are not that many actually if you count only the users, not the
files that define them, and you ignore the files in drivers/gpio 
that define their own.

drivers/ata/pata_rb532_cf.c:    gpio = irq_to_gpio(irq);
drivers/input/touchscreen/eeti_ts.c:    return gpio_get_value(irq_to_gpio(priv->irq)) == priv->irq_active_high;
drivers/input/touchscreen/egalax_ts.c:  int gpio = irq_to_gpio(client->irq);
drivers/mfd/ezx-pcap.c: } while (gpio_get_value(irq_to_gpio(pcap->spi->irq)));
drivers/pcmcia/db1xxx_ss.c:     return !gpio_get_value(irq_to_gpio(sock->insert_irq));
drivers/power/tosa_battery.c:   pr_info("tosa_bat_gpio irq: %d\n", gpio_get_value(irq_to_gpio(irq)));
drivers/staging/iio/accel/lis3l02dq_core.c:     if (spi->irq && gpio_is_valid(irq_to_gpio(spi->irq)) > 0) {
drivers/staging/iio/accel/lis3l02dq_core.c:     if (spi->irq && gpio_is_valid(irq_to_gpio(spi->irq)) > 0)
drivers/staging/iio/accel/lis3l02dq_core.c:     if (spi->irq && gpio_is_valid(irq_to_gpio(spi->irq)) > 0)
drivers/staging/iio/accel/lis3l02dq_ring.c:             if (gpio_get_value(irq_to_gpio(st->us->irq)))

The pata_rb532_cf and db1xxx_ss drivers are only used on MIPS,
most of the other ones are for arm/pxa and are currently broken.

> I'm looking at drivers/input/touchscreen/egalax_ts.c driver.
> It failed to compile without irq_to_gpio. It's a i2c client device and
> use irq line configured as gpio to wakeup touchscreen controller.
> If we don't have irq_to_gpio, I'm afraid it has to use plat data or
> of property to pass gpio number.

Yes, I think that is correct. The drivers should really have been
fixed at the time when the irq_to_gpio function was removed from
the respective platforms using those drivers, and in some cases
this has already happened.

	Arnd