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-mcp23s08.c

@@ -446,7 +446,7 @@ static int mcp23s08_irq_reqres(struct irq_data *data)
 	struct mcp23s08 *mcp = irq_data_get_irq_chip_data(data);
 
 	if (gpiochip_lock_as_irq(&mcp->chip, data->hwirq)) {
-		dev_err(mcp->chip.dev,
+		dev_err(mcp->chip.parent,
 			"unable to lock HW IRQ %lu for IRQ usage\n",
 			data->hwirq);
 		return -EINVAL;
@@ -481,7 +481,8 @@ static int mcp23s08_irq_setup(struct mcp23s08 *mcp)
 
 	mutex_init(&mcp->irq_lock);
 
-	mcp->irq_domain = irq_domain_add_linear(chip->dev->of_node, chip->ngpio,
+	mcp->irq_domain = irq_domain_add_linear(chip->parent->of_node,
+						chip->ngpio,
 						&irq_domain_simple_ops, mcp);
 	if (!mcp->irq_domain)
 		return -ENODEV;
@@ -491,10 +492,11 @@ static int mcp23s08_irq_setup(struct mcp23s08 *mcp)
 	else
 		irqflags |= IRQF_TRIGGER_LOW;
 
-	err = devm_request_threaded_irq(chip->dev, mcp->irq, NULL, mcp23s08_irq,
-					irqflags, dev_name(chip->dev), mcp);
+	err = devm_request_threaded_irq(chip->parent, mcp->irq, NULL,
+					mcp23s08_irq,
+					irqflags, dev_name(chip->parent), mcp);
 	if (err != 0) {
-		dev_err(chip->dev, "unable to request IRQ#%d: %d\n",
+		dev_err(chip->parent, "unable to request IRQ#%d: %d\n",
 			mcp->irq, err);
 		return err;
 	}
@@ -638,7 +640,7 @@ static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
 
 	mcp->chip.base = pdata->base;
 	mcp->chip.can_sleep = true;
-	mcp->chip.dev = dev;
+	mcp->chip.parent = dev;
 	mcp->chip.owner = THIS_MODULE;
 
 	/* verify MCP_IOCON.SEQOP = 0, so sequential reads work,
@@ -652,7 +654,7 @@ static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
 	mcp->irq_controller = pdata->irq_controller;
 	if (mcp->irq && mcp->irq_controller) {
 		mcp->irq_active_high =
-			of_property_read_bool(mcp->chip.dev->of_node,
+			of_property_read_bool(mcp->chip.parent->of_node,
 					      "microchip,irq-active-high");
 
 		if (type == MCP_TYPE_017)