gpio: change member .dev to .parent

The name .dev in a struct is normally reserved for a struct device
that is let us say a superclass to the thing described by the struct.
struct gpio_chip stands out by confusingly using a struct device *dev
to point to the parent device (such as a platform_device) that
represents the hardware. As we want to give gpio_chip:s real devices,
this is not working. We need to rename this member to parent.

This was done by two coccinelle scripts, I guess it is possible to
combine them into one, but I don't know such stuff. They look like
this:

@@
struct gpio_chip *var;
@@
-var->dev
+var->parent

and:

@@
struct gpio_chip var;
@@
-var.dev
+var.parent

and:

@@
struct bgpio_chip *var;
@@
-var->gc.dev
+var->gc.parent

Plus a few instances of bgpio that I couldn't figure out how
to teach Coccinelle to rewrite.

This patch hits all over the place, but I *strongly* prefer this
solution to any piecemal approaches that just exercise patch
mechanics all over the place. It mainly hits drivers/gpio and
drivers/pinctrl which is my own backyard anyway.

Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Rafał Miłecki <zajec5@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: Alek Du <alek.du@intel.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Acked-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-dln2.c

@@ -377,7 +377,7 @@ static void dln2_irq_bus_unlock(struct irq_data *irqd)
 
 		ret = dln2_gpio_set_event_cfg(dln2, pin, type, 0);
 		if (ret)
-			dev_err(dln2->gpio.dev, "failed to set event\n");
+			dev_err(dln2->gpio.parent, "failed to set event\n");
 	}
 
 	mutex_unlock(&dln2->irq_lock);
@@ -406,19 +406,19 @@ static void dln2_gpio_event(struct platform_device *pdev, u16 echo,
 	struct dln2_gpio *dln2 = platform_get_drvdata(pdev);
 
 	if (len < sizeof(*event)) {
-		dev_err(dln2->gpio.dev, "short event message\n");
+		dev_err(dln2->gpio.parent, "short event message\n");
 		return;
 	}
 
 	pin = le16_to_cpu(event->pin);
 	if (pin >= dln2->gpio.ngpio) {
-		dev_err(dln2->gpio.dev, "out of bounds pin %d\n", pin);
+		dev_err(dln2->gpio.parent, "out of bounds pin %d\n", pin);
 		return;
 	}
 
 	irq = irq_find_mapping(dln2->gpio.irqdomain, pin);
 	if (!irq) {
-		dev_err(dln2->gpio.dev, "pin %d not mapped to IRQ\n", pin);
+		dev_err(dln2->gpio.parent, "pin %d not mapped to IRQ\n", pin);
 		return;
 	}
 
@@ -462,7 +462,7 @@ static int dln2_gpio_probe(struct platform_device *pdev)
 	dln2->pdev = pdev;
 
 	dln2->gpio.label = "dln2";
-	dln2->gpio.dev = dev;
+	dln2->gpio.parent = dev;
 	dln2->gpio.owner = THIS_MODULE;
 	dln2->gpio.base = -1;
 	dln2->gpio.ngpio = pins;