soc: fsl: qe: Drop legacy-of-mm-gpiochip.h header from GPIO driver

Remove legacy-of-mm-gpiochip.h header file. The above mentioned
file provides an OF API that's deprecated. There is no agnostic
alternatives to it and we have to open code the logic which was
hidden behind of_mm_gpiochip_add_data(). Note, most of the GPIO
drivers are using their own labeling schemas and resource retrieval
that only a few may gain of the code deduplication, so whenever
alternative is appear we can move drivers again to use that one.

As a side effect this change fixes a potential memory leak on
an error path, if of_mm_gpiochip_add_data() fails.

[Text copied from commit 34064c8267a6 ("powerpc/8xx: Drop
legacy-of-mm-gpiochip.h header")]

Suggested-by: Bartosz Golaszewski <[e-mail]>
Reviewed-by: Bartosz Golaszewski <[e-mail]>
Link: https://lore.kernel.org/r/e8a5d2c5[e-mail]
Signed-off-by: Christophe Leroy <[e-mail]>

arch/powerpc/platforms/Kconfig

···
 	bool "QE GPIO support"
 	depends on QUICC_ENGINE
 	select GPIOLIB
-	select OF_GPIO_MM_GPIOCHIP
 	help
 	  Say Y here if you're going to use hardware that connects to the
 	  QE GPIOs.

drivers/soc/fsl/qe/gpio.c

···
 #include <linux/spinlock.h>
 #include <linux/err.h>
 #include <linux/io.h>
-#include <linux/gpio/legacy-of-mm-gpiochip.h>
 #include <linux/gpio/consumer.h>
 #include <linux/gpio/driver.h>
 #include <linux/slab.h>
···
 #define PIN_MASK(gpio) (1UL << (QE_PIO_PINS - 1 - (gpio)))
 
 struct qe_gpio_chip {
-	struct of_mm_gpio_chip mm_gc;
+	struct gpio_chip gc;
+	void __iomem *regs;
 	spinlock_t lock;
 
 	/* shadowed data register to clear/set bits safely */
···
 	struct qe_pio_regs saved_regs;
 };
 
-static void qe_gpio_save_regs(struct of_mm_gpio_chip *mm_gc)
+static void qe_gpio_save_regs(struct qe_gpio_chip *qe_gc)
 {
-	struct qe_gpio_chip *qe_gc =
-		container_of(mm_gc, struct qe_gpio_chip, mm_gc);
-	struct qe_pio_regs __iomem *regs = mm_gc->regs;
+	struct qe_pio_regs __iomem *regs = qe_gc->regs;
 
 	qe_gc->cpdata = ioread32be(&regs->cpdata);
 	qe_gc->saved_regs.cpdata = qe_gc->cpdata;
···
 
 static int qe_gpio_get(struct gpio_chip *gc, unsigned int gpio)
 {
-	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
-	struct qe_pio_regs __iomem *regs = mm_gc->regs;
+	struct qe_gpio_chip *qe_gc = gpiochip_get_data(gc);
+	struct qe_pio_regs __iomem *regs = qe_gc->regs;
 	u32 pin_mask = PIN_MASK(gpio);
 
 	return !!(ioread32be(&regs->cpdata) & pin_mask);
···
 
 static int qe_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
 {
-	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
 	struct qe_gpio_chip *qe_gc = gpiochip_get_data(gc);
-	struct qe_pio_regs __iomem *regs = mm_gc->regs;
+	struct qe_pio_regs __iomem *regs = qe_gc->regs;
 	unsigned long flags;
 	u32 pin_mask = PIN_MASK(gpio);
 
···
 static int qe_gpio_set_multiple(struct gpio_chip *gc,
 				unsigned long *mask, unsigned long *bits)
 {
-	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
 	struct qe_gpio_chip *qe_gc = gpiochip_get_data(gc);
-	struct qe_pio_regs __iomem *regs = mm_gc->regs;
+	struct qe_pio_regs __iomem *regs = qe_gc->regs;
 	unsigned long flags;
 	int i;
 
···
 
 static int qe_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
 {
-	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
 	struct qe_gpio_chip *qe_gc = gpiochip_get_data(gc);
 	unsigned long flags;
 
 	spin_lock_irqsave(&qe_gc->lock, flags);
 
-	__par_io_config_pin(mm_gc->regs, gpio, QE_PIO_DIR_IN, 0, 0, 0);
+	__par_io_config_pin(qe_gc->regs, gpio, QE_PIO_DIR_IN, 0, 0, 0);
 
 	spin_unlock_irqrestore(&qe_gc->lock, flags);
 
···
 
 static int qe_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
 {
-	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
 	struct qe_gpio_chip *qe_gc = gpiochip_get_data(gc);
 	unsigned long flags;
 
···
 
 	spin_lock_irqsave(&qe_gc->lock, flags);
 
-	__par_io_config_pin(mm_gc->regs, gpio, QE_PIO_DIR_OUT, 0, 0, 0);
+	__par_io_config_pin(qe_gc->regs, gpio, QE_PIO_DIR_OUT, 0, 0, 0);
 
 	spin_unlock_irqrestore(&qe_gc->lock, flags);
 
···
 void qe_pin_set_dedicated(struct qe_pin *qe_pin)
 {
 	struct qe_gpio_chip *qe_gc = qe_pin->controller;
-	struct qe_pio_regs __iomem *regs = qe_gc->mm_gc.regs;
+	struct qe_pio_regs __iomem *regs = qe_gc->regs;
 	struct qe_pio_regs *sregs = &qe_gc->saved_regs;
 	int pin = qe_pin->num;
 	u32 mask1 = 1 << (QE_PIO_PINS - (pin + 1));
···
 
 	iowrite32be(qe_gc->cpdata, &regs->cpdata);
 	qe_clrsetbits_be32(&regs->cpodr, mask1, sregs->cpodr & mask1);
-
 	spin_unlock_irqrestore(&qe_gc->lock, flags);
 }
 EXPORT_SYMBOL(qe_pin_set_dedicated);
···
 void qe_pin_set_gpio(struct qe_pin *qe_pin)
 {
 	struct qe_gpio_chip *qe_gc = qe_pin->controller;
-	struct qe_pio_regs __iomem *regs = qe_gc->mm_gc.regs;
+	struct qe_pio_regs __iomem *regs = qe_gc->regs;
 	unsigned long flags;
 
 	spin_lock_irqsave(&qe_gc->lock, flags);
···
 	struct device *dev = &ofdev->dev;
 	struct device_node *np = dev->of_node;
 	struct qe_gpio_chip *qe_gc;
-	struct of_mm_gpio_chip *mm_gc;
 	struct gpio_chip *gc;
 
 	qe_gc = devm_kzalloc(dev, sizeof(*qe_gc), GFP_KERNEL);
···
 
 	spin_lock_init(&qe_gc->lock);
 
-	mm_gc = &qe_gc->mm_gc;
-	gc = &mm_gc->gc;
+	gc = &qe_gc->gc;
 
-	mm_gc->save_regs = qe_gpio_save_regs;
+	gc->base = -1;
 	gc->ngpio = QE_PIO_PINS;
 	gc->direction_input = qe_gpio_dir_in;
 	gc->direction_output = qe_gpio_dir_out;
 	gc->get = qe_gpio_get;
 	gc->set = qe_gpio_set;
 	gc->set_multiple = qe_gpio_set_multiple;
+	gc->parent = dev;
+	gc->owner = THIS_MODULE;
 
-	return of_mm_gpiochip_add_data(np, mm_gc, qe_gc);
+	gc->label = devm_kasprintf(dev, GFP_KERNEL, "%pOF", np);
+	if (!gc->label)
+		return -ENOMEM;
+
+	qe_gc->regs = devm_of_iomap(dev, np, 0, NULL);
+	if (IS_ERR(qe_gc->regs))
+		return PTR_ERR(qe_gc->regs);
+
+	qe_gpio_save_regs(qe_gc);
+
+	return devm_gpiochip_add_data(dev, gc, qe_gc);
 }
 
 static const struct of_device_id qe_gpio_match[] = {