gpio: generic: factor into gpio_chip struct

The separate struct bgpio_chip has been a pain to handle, both
by being confusingly similar in name to struct gpio_chip and
for being contained inside a struct so that struct gpio_chip
is contained in a struct contained in a struct, making several
steps of dereferencing necessary.

Make things simpler: include the fields directly into
<linux/gpio/driver.h>, #ifdef:ed for CONFIG_GENERIC_GPIO, and
get rid of the <linux/basic_mmio_gpio.h> altogether. Prefix
some of the member variables with bgpio_* and add proper
kerneldoc while we're at it.

Modify all users to handle the change and use a struct
gpio_chip directly. And while we're at it: replace all
container_of() dereferencing by gpiochip_get_data() and
registering the gpio_chip with gpiochip_add_data().

Cc: arm@kernel.org
Cc: Alexander Shiyan <shc_work@mail.ru>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Olof Johansson <olof@lixom.net>
Cc: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Cc: Rabin Vincent <rabin@rab.in>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-omap@vger.kernel.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: bcm-kernel-feedback-list@broadcom.com
Acked-by: Gregory Fong <gregory.0xf0@gmail.com>
Acked-by: Liviu Dudau <Liviu.Dudau@arm.com>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpio-moxart.c b/drivers/gpio/gpio-moxart.c
index 8942f49..71c13c4 100644
--- a/drivers/gpio/gpio-moxart.c
+++ b/drivers/gpio/gpio-moxart.c
@@ -14,7 +14,6 @@
 #include <linux/init.h>
 #include <linux/irq.h>
 #include <linux/io.h>
-#include <linux/gpio.h>
 #include <linux/platform_device.h>
 #include <linux/module.h>
 #include <linux/of_address.h>
@@ -23,7 +22,7 @@
 #include <linux/delay.h>
 #include <linux/timer.h>
 #include <linux/bitops.h>
-#include <linux/basic_mmio_gpio.h>
+#include <linux/gpio/driver.h>
 
 #define GPIO_DATA_OUT		0x00
 #define GPIO_DATA_IN		0x04
@@ -33,12 +32,12 @@
 {
 	struct device *dev = &pdev->dev;
 	struct resource *res;
-	struct bgpio_chip *bgc;
+	struct gpio_chip *gc;
 	void __iomem *base;
 	int ret;
 
-	bgc = devm_kzalloc(dev, sizeof(*bgc), GFP_KERNEL);
-	if (!bgc)
+	gc = devm_kzalloc(dev, sizeof(*gc), GFP_KERNEL);
+	if (!gc)
 		return -ENOMEM;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -46,7 +45,7 @@
 	if (IS_ERR(base))
 		return PTR_ERR(base);
 
-	ret = bgpio_init(bgc, dev, 4, base + GPIO_DATA_IN,
+	ret = bgpio_init(gc, dev, 4, base + GPIO_DATA_IN,
 			 base + GPIO_DATA_OUT, NULL,
 			 base + GPIO_PIN_DIRECTION, NULL,
 			 BGPIOF_READ_OUTPUT_REG_SET);
@@ -55,16 +54,16 @@
 		return ret;
 	}
 
-	bgc->gc.label = "moxart-gpio";
-	bgc->gc.request = gpiochip_generic_request;
-	bgc->gc.free = gpiochip_generic_free;
-	bgc->data = bgc->read_reg(bgc->reg_set);
-	bgc->gc.base = 0;
-	bgc->gc.ngpio = 32;
-	bgc->gc.parent = dev;
-	bgc->gc.owner = THIS_MODULE;
+	gc->label = "moxart-gpio";
+	gc->request = gpiochip_generic_request;
+	gc->free = gpiochip_generic_free;
+	gc->bgpio_data = bgc->read_reg(bgc->reg_set);
+	gc->base = 0;
+	gc->ngpio = 32;
+	gc->parent = dev;
+	gc->owner = THIS_MODULE;
 
-	ret = gpiochip_add(&bgc->gc);
+	ret = gpiochip_add_data(gc, NULL);
 	if (ret) {
 		dev_err(dev, "%s: gpiochip_add failed\n",
 			dev->of_node->full_name);