1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * A gpio chip driver for TXx9 SoCs
4 *
5 * Copyright (C) 2008 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
6 */
7
8 #include <linux/init.h>
9 #include <linux/spinlock.h>
10 #include <linux/gpio/driver.h>
11 #include <linux/errno.h>
12 #include <linux/io.h>
13 #include <asm/txx9pio.h>
14
15 static DEFINE_SPINLOCK(txx9_gpio_lock);
16
17 static struct txx9_pio_reg __iomem *txx9_pioptr;
18
19 static int txx9_gpio_get(struct gpio_chip *chip, unsigned int offset)
20 {
21 return !!(__raw_readl(&txx9_pioptr->din) & (1 << offset));
22 }
23
24 static void txx9_gpio_set_raw(unsigned int offset, int value)
25 {
26 u32 val;
27 val = __raw_readl(&txx9_pioptr->dout);
28 if (value)
29 val |= 1 << offset;
30 else
31 val &= ~(1 << offset);
32 __raw_writel(val, &txx9_pioptr->dout);
33 }
34
35 static void txx9_gpio_set(struct gpio_chip *chip, unsigned int offset,
36 int value)
37 {
38 unsigned long flags;
39 spin_lock_irqsave(&txx9_gpio_lock, flags);
40 txx9_gpio_set_raw(offset, value);
41 mmiowb();
42 spin_unlock_irqrestore(&txx9_gpio_lock, flags);
43 }
44
45 static int txx9_gpio_dir_in(struct gpio_chip *chip, unsigned int offset)
46 {
47 unsigned long flags;
48 spin_lock_irqsave(&txx9_gpio_lock, flags);
49 __raw_writel(__raw_readl(&txx9_pioptr->dir) & ~(1 << offset),
50 &txx9_pioptr->dir);
51 mmiowb();
52 spin_unlock_irqrestore(&txx9_gpio_lock, flags);
53 return 0;
54 }
55
56 static int txx9_gpio_dir_out(struct gpio_chip *chip, unsigned int offset,
57 int value)
58 {
59 unsigned long flags;
60 spin_lock_irqsave(&txx9_gpio_lock, flags);
61 txx9_gpio_set_raw(offset, value);
62 __raw_writel(__raw_readl(&txx9_pioptr->dir) | (1 << offset),
63 &txx9_pioptr->dir);
64 mmiowb();
65 spin_unlock_irqrestore(&txx9_gpio_lock, flags);
66 return 0;
67 }
68
69 static struct gpio_chip txx9_gpio_chip = {
70 .get = txx9_gpio_get,
71 .set = txx9_gpio_set,
72 .direction_input = txx9_gpio_dir_in,
73 .direction_output = txx9_gpio_dir_out,
74 .label = "TXx9",
75 };
76
77 int __init txx9_gpio_init(unsigned long baseaddr,
78 unsigned int base, unsigned int num)
79 {
80 txx9_pioptr = ioremap(baseaddr, sizeof(struct txx9_pio_reg));
81 if (!txx9_pioptr)
82 return -ENODEV;
83 txx9_gpio_chip.base = base;
84 txx9_gpio_chip.ngpio = num;
85 return gpiochip_add_data(&txx9_gpio_chip, NULL);
86 }
87
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.