1 // SPDX-License-Identifier: GPL-2.0
3 * arch/sh/boards/mach-x3proto/gpio.c
5 * Renesas SH-X3 Prototype Baseboard GPIO Support.
7 * Copyright (C) 2010 - 2012 Paul Mundt
9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11 #include <linux/init.h>
12 #include <linux/interrupt.h>
13 #include <linux/gpio/driver.h>
14 #include <linux/irq.h>
15 #include <linux/kernel.h>
16 #include <linux/spinlock.h>
17 #include <linux/irqdomain.h>
19 #include <mach/ilsel.h>
20 #include <mach/hardware.h>
22 #define KEYCTLR 0xb81c0000
23 #define KEYOUTR 0xb81c0002
24 #define KEYDETR 0xb81c0004
26 static DEFINE_SPINLOCK(x3proto_gpio_lock);
27 static struct irq_domain *x3proto_irq_domain;
29 static int x3proto_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
34 spin_lock_irqsave(&x3proto_gpio_lock, flags);
35 data = __raw_readw(KEYCTLR);
37 __raw_writew(data, KEYCTLR);
38 spin_unlock_irqrestore(&x3proto_gpio_lock, flags);
43 static int x3proto_gpio_get(struct gpio_chip *chip, unsigned gpio)
45 return !!(__raw_readw(KEYDETR) & (1 << gpio));
48 static int x3proto_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
52 if (gpio < chip->ngpio)
53 virq = irq_create_mapping(x3proto_irq_domain, gpio);
60 static void x3proto_gpio_irq_handler(struct irq_desc *desc)
62 struct irq_data *data = irq_desc_get_irq_data(desc);
63 struct irq_chip *chip = irq_data_get_irq_chip(data);
67 chip->irq_mask_ack(data);
69 mask = __raw_readw(KEYDETR);
70 for_each_set_bit(pin, &mask, NR_BASEBOARD_GPIOS)
71 generic_handle_domain_irq(x3proto_irq_domain, pin);
73 chip->irq_unmask(data);
76 struct gpio_chip x3proto_gpio_chip = {
77 .label = "x3proto-gpio",
78 .direction_input = x3proto_gpio_direction_input,
79 .get = x3proto_gpio_get,
80 .to_irq = x3proto_gpio_to_irq,
82 .ngpio = NR_BASEBOARD_GPIOS,
85 static int x3proto_gpio_irq_map(struct irq_domain *domain, unsigned int virq,
86 irq_hw_number_t hwirq)
88 irq_set_chip_and_handler_name(virq, &dummy_irq_chip, handle_simple_irq,
94 static struct irq_domain_ops x3proto_gpio_irq_ops = {
95 .map = x3proto_gpio_irq_map,
96 .xlate = irq_domain_xlate_twocell,
99 int __init x3proto_gpio_setup(void)
103 ilsel = ilsel_enable(ILSEL_KEY);
104 if (unlikely(ilsel < 0))
107 ret = gpiochip_add_data(&x3proto_gpio_chip, NULL);
111 x3proto_irq_domain = irq_domain_add_linear(NULL, NR_BASEBOARD_GPIOS,
112 &x3proto_gpio_irq_ops, NULL);
113 if (unlikely(!x3proto_irq_domain))
116 pr_info("registering '%s' support, handling GPIOs %u -> %u, "
118 x3proto_gpio_chip.label, x3proto_gpio_chip.base,
119 x3proto_gpio_chip.base + x3proto_gpio_chip.ngpio,
122 irq_set_chained_handler(ilsel, x3proto_gpio_irq_handler);
123 irq_set_irq_wake(ilsel, 1);
128 gpiochip_remove(&x3proto_gpio_chip);
131 synchronize_irq(ilsel);
133 ilsel_disable(ILSEL_KEY);