arm: at91: at91sam9x5: fix gpio number per bank

On the at91sam9x5 SoC series, GPIO banks B and D only have 19 and 22
pins. So add a property to set this parameter.

Acked-by: Nicolas Ferre <[e-mail]>
Acked-by: Linus Walleij <[e-mail]>
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <[e-mail]>

Documentation/devicetree/bindings/gpio/gpio_atmel.txt

···
   unused).
 - gpio-controller: Marks the device node as a GPIO controller.
 
+optional properties:
+- #gpio-lines: Number of gpio if absent 32.
+
+
 Example:
 	pioA: gpio@fffff200 {
 		compatible = "atmel,at91rm9200-gpio";
···
 		interrupts = <2 4>;
 		#gpio-cells = <2>;
 		gpio-controller;
+		#gpio-lines = <19>;
 	};
 

arch/arm/boot/dts/at91sam9x5.dtsi

···
 					interrupts = <2 4 1>;
 					#gpio-cells = <2>;
 					gpio-controller;
+					#gpio-lines = <19>;
 					interrupt-controller;
 					#interrupt-cells = <2>;
 				};
···
 					interrupts = <3 4 1>;
 					#gpio-cells = <2>;
 					gpio-controller;
+					#gpio-lines = <22>;
 					interrupt-controller;
 					#interrupt-cells = <2>;
 				};

arch/arm/mach-at91/gpio.c

···
 
 #include "generic.h"
 
+#define MAX_NB_GPIO_PER_BANK	32
+
 struct at91_gpio_chip {
 	struct gpio_chip	chip;
 	struct at91_gpio_chip	*next;		/* Bank sharing same clock */
···
 					unsigned offset);
 static int at91_gpiolib_to_irq(struct gpio_chip *chip, unsigned offset);
 
-#define AT91_GPIO_CHIP(name, nr_gpio)					\
+#define AT91_GPIO_CHIP(name)						\
 	{								\
 		.chip = {						\
 			.label		  = name,			\
···
 			.set		  = at91_gpiolib_set,		\
 			.dbg_show	  = at91_gpiolib_dbg_show,	\
 			.to_irq		  = at91_gpiolib_to_irq,	\
-			.ngpio		  = nr_gpio,			\
+			.ngpio		  = MAX_NB_GPIO_PER_BANK,	\
 		},							\
 	}
 
 static struct at91_gpio_chip gpio_chip[] = {
-	AT91_GPIO_CHIP("pioA", 32),
-	AT91_GPIO_CHIP("pioB", 32),
-	AT91_GPIO_CHIP("pioC", 32),
-	AT91_GPIO_CHIP("pioD", 32),
-	AT91_GPIO_CHIP("pioE", 32),
+	AT91_GPIO_CHIP("pioA"),
+	AT91_GPIO_CHIP("pioB"),
+	AT91_GPIO_CHIP("pioC"),
+	AT91_GPIO_CHIP("pioD"),
+	AT91_GPIO_CHIP("pioE"),
 };
 
 static int gpio_banks;
···
 
 static inline void __iomem *pin_to_controller(unsigned pin)
 {
-	pin /= 32;
+	pin /= MAX_NB_GPIO_PER_BANK;
 	if (likely(pin < gpio_banks))
 		return gpio_chip[pin].regbase;
 
···
 
 static inline unsigned pin_to_mask(unsigned pin)
 {
-	return 1 << (pin % 32);
+	return 1 << (pin % MAX_NB_GPIO_PER_BANK);
 }
 
 
···
 {
 	int alias_idx;
 	struct at91_gpio_chip *at91_gpio;
+	uint32_t ngpio;
 
 	if (!np)
 		return;
···
 	}
 
 	at91_gpio = &gpio_chip[alias_idx];
-	at91_gpio->chip.base = alias_idx * at91_gpio->chip.ngpio;
+	at91_gpio->chip.base = alias_idx * MAX_NB_GPIO_PER_BANK;
 
 	at91_gpio->regbase = of_iomap(np, 0);
 	if (!at91_gpio->regbase) {
···
 	/* Get capabilities from compatibility property */
 	if (of_device_is_compatible(np, "atmel,at91sam9x5-gpio"))
 		at91_gpio_caps |= AT91_GPIO_CAP_PIO3;
+
+	if (!of_property_read_u32(np, "#gpio-lines", &ngpio)) {
+		if (ngpio >= MAX_NB_GPIO_PER_BANK)
+			pr_err("at91_gpio.%d, gpio-nb >= %d failback to %d\n",
+			       alias_idx, MAX_NB_GPIO_PER_BANK, MAX_NB_GPIO_PER_BANK);
+		else
+			at91_gpio->chip.ngpio = ngpio;
+	}
 
 	/* Setup clock */
 	if (at91_gpio_setup_clk(alias_idx))
···
 {
 	struct at91_gpio_chip *at91_gpio = &gpio_chip[idx];
 
-	at91_gpio->chip.base = idx * at91_gpio->chip.ngpio;
+	at91_gpio->chip.base = idx * MAX_NB_GPIO_PER_BANK;
 	at91_gpio->pioc_hwirq = pioc_hwirq;
 	at91_gpio->pioc_idx = idx;