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>

drivers/gpio/gpio-xgene-sb.c

@@ -23,10 +23,8 @@
 #include <linux/io.h>
 #include <linux/platform_device.h>
 #include <linux/of_gpio.h>
-#include <linux/gpio.h>
 #include <linux/gpio/driver.h>
 #include <linux/acpi.h>
-#include <linux/basic_mmio_gpio.h>
 
 #include "gpiolib.h"
 
@@ -43,38 +41,31 @@
 
 /**
  * struct xgene_gpio_sb - GPIO-Standby private data structure.
- * @bgc:			memory-mapped GPIO controllers.
+ * @gc:				memory-mapped GPIO controllers.
  * @irq:			Mapping GPIO pins and interrupt number
  * nirq:			Number of GPIO pins that supports interrupt
  */
 struct xgene_gpio_sb {
-	struct bgpio_chip	bgc;
+	struct gpio_chip	gc;
 	u32 *irq;
 	u32 nirq;
 };
 
-static inline struct xgene_gpio_sb *to_xgene_gpio_sb(struct gpio_chip *gc)
-{
-	struct bgpio_chip *bgc = to_bgpio_chip(gc);
-
-	return container_of(bgc, struct xgene_gpio_sb, bgc);
-}
-
-static void xgene_gpio_set_bit(struct bgpio_chip *bgc, void __iomem *reg, u32 gpio, int val)
+static void xgene_gpio_set_bit(struct gpio_chip *gc, void __iomem *reg, u32 gpio, int val)
 {
 	u32 data;
 
-	data = bgc->read_reg(reg);
+	data = gc->read_reg(reg);
 	if (val)
 		data |= GPIO_MASK(gpio);
 	else
 		data &= ~GPIO_MASK(gpio);
-	bgc->write_reg(reg, data);
+	gc->write_reg(reg, data);
 }
 
 static int apm_gpio_sb_to_irq(struct gpio_chip *gc, u32 gpio)
 {
-	struct xgene_gpio_sb *priv = to_xgene_gpio_sb(gc);
+	struct xgene_gpio_sb *priv = gpiochip_get_data(gc);
 
 	if (priv->irq[gpio])
 		return priv->irq[gpio];
@@ -99,15 +90,15 @@ static int xgene_gpio_sb_probe(struct platform_device *pdev)
 	if (IS_ERR(regs))
 		return PTR_ERR(regs);
 
-	ret = bgpio_init(&priv->bgc, &pdev->dev, 4,
+	ret = bgpio_init(&priv->gc, &pdev->dev, 4,
 			regs + MPA_GPIO_IN_ADDR,
 			regs + MPA_GPIO_OUT_ADDR, NULL,
 			regs + MPA_GPIO_OE_ADDR, NULL, 0);
         if (ret)
                 return ret;
 
-	priv->bgc.gc.to_irq = apm_gpio_sb_to_irq;
-	priv->bgc.gc.ngpio = XGENE_MAX_GPIO_DS;
+	priv->gc.to_irq = apm_gpio_sb_to_irq;
+	priv->gc.ngpio = XGENE_MAX_GPIO_DS;
 
 	priv->nirq = XGENE_MAX_GPIO_DS_IRQ;
 
@@ -118,14 +109,14 @@ static int xgene_gpio_sb_probe(struct platform_device *pdev)
 
 	for (i = 0; i < priv->nirq; i++) {
 		priv->irq[default_lines[i]] = platform_get_irq(pdev, i);
-		xgene_gpio_set_bit(&priv->bgc, regs + MPA_GPIO_SEL_LO,
+		xgene_gpio_set_bit(&priv->gc, regs + MPA_GPIO_SEL_LO,
                                    default_lines[i] * 2, 1);
-		xgene_gpio_set_bit(&priv->bgc, regs + MPA_GPIO_INT_LVL, i, 1);
+		xgene_gpio_set_bit(&priv->gc, regs + MPA_GPIO_INT_LVL, i, 1);
 	}
 
 	platform_set_drvdata(pdev, priv);
 
-	ret = gpiochip_add(&priv->bgc.gc);
+	ret = gpiochip_add_data(&priv->gc, priv);
 	if (ret)
 		dev_err(&pdev->dev, "failed to register X-Gene GPIO Standby driver\n");
 	else
@@ -133,7 +124,7 @@ static int xgene_gpio_sb_probe(struct platform_device *pdev)
 
 	if (priv->nirq > 0) {
 		/* Register interrupt handlers for gpio signaled acpi events */
-		acpi_gpiochip_request_interrupts(&priv->bgc.gc);
+		acpi_gpiochip_request_interrupts(&priv->gc);
 	}
 
 	return ret;
@@ -144,10 +135,11 @@ static int xgene_gpio_sb_remove(struct platform_device *pdev)
 	struct xgene_gpio_sb *priv = platform_get_drvdata(pdev);
 
 	if (priv->nirq > 0) {
-		acpi_gpiochip_free_interrupts(&priv->bgc.gc);
+		acpi_gpiochip_free_interrupts(&priv->gc);
 	}
 
-	return bgpio_remove(&priv->bgc);
+	gpiochip_remove(&priv->gc);
+	return 0;
 }
 
 static const struct of_device_id xgene_gpio_sb_of_match[] = {