~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/arch/powerpc/sysdev/simple_gpio.c

Version: ~ [ linux-5.5-rc1 ] ~ [ linux-5.4.2 ] ~ [ linux-5.3.15 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.88 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.158 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.206 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.206 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.78 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /*
  2  * Simple Memory-Mapped GPIOs
  3  *
  4  * Copyright (c) MontaVista Software, Inc. 2008.
  5  *
  6  * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
  7  *
  8  * This program is free software; you can redistribute  it and/or modify it
  9  * under  the terms of  the GNU General  Public License as published by the
 10  * Free Software Foundation;  either version 2 of the  License, or (at your
 11  * option) any later version.
 12  */
 13 
 14 #include <linux/init.h>
 15 #include <linux/kernel.h>
 16 #include <linux/spinlock.h>
 17 #include <linux/types.h>
 18 #include <linux/ioport.h>
 19 #include <linux/io.h>
 20 #include <linux/of.h>
 21 #include <linux/of_gpio.h>
 22 #include <linux/gpio/driver.h>
 23 #include <linux/slab.h>
 24 #include <asm/prom.h>
 25 #include "simple_gpio.h"
 26 
 27 struct u8_gpio_chip {
 28         struct of_mm_gpio_chip mm_gc;
 29         spinlock_t lock;
 30 
 31         /* shadowed data register to clear/set bits safely */
 32         u8 data;
 33 };
 34 
 35 static u8 u8_pin2mask(unsigned int pin)
 36 {
 37         return 1 << (8 - 1 - pin);
 38 }
 39 
 40 static int u8_gpio_get(struct gpio_chip *gc, unsigned int gpio)
 41 {
 42         struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
 43 
 44         return !!(in_8(mm_gc->regs) & u8_pin2mask(gpio));
 45 }
 46 
 47 static void u8_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
 48 {
 49         struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
 50         struct u8_gpio_chip *u8_gc = gpiochip_get_data(gc);
 51         unsigned long flags;
 52 
 53         spin_lock_irqsave(&u8_gc->lock, flags);
 54 
 55         if (val)
 56                 u8_gc->data |= u8_pin2mask(gpio);
 57         else
 58                 u8_gc->data &= ~u8_pin2mask(gpio);
 59 
 60         out_8(mm_gc->regs, u8_gc->data);
 61 
 62         spin_unlock_irqrestore(&u8_gc->lock, flags);
 63 }
 64 
 65 static int u8_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
 66 {
 67         return 0;
 68 }
 69 
 70 static int u8_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
 71 {
 72         u8_gpio_set(gc, gpio, val);
 73         return 0;
 74 }
 75 
 76 static void u8_gpio_save_regs(struct of_mm_gpio_chip *mm_gc)
 77 {
 78         struct u8_gpio_chip *u8_gc =
 79                 container_of(mm_gc, struct u8_gpio_chip, mm_gc);
 80 
 81         u8_gc->data = in_8(mm_gc->regs);
 82 }
 83 
 84 static int __init u8_simple_gpiochip_add(struct device_node *np)
 85 {
 86         int ret;
 87         struct u8_gpio_chip *u8_gc;
 88         struct of_mm_gpio_chip *mm_gc;
 89         struct gpio_chip *gc;
 90 
 91         u8_gc = kzalloc(sizeof(*u8_gc), GFP_KERNEL);
 92         if (!u8_gc)
 93                 return -ENOMEM;
 94 
 95         spin_lock_init(&u8_gc->lock);
 96 
 97         mm_gc = &u8_gc->mm_gc;
 98         gc = &mm_gc->gc;
 99 
100         mm_gc->save_regs = u8_gpio_save_regs;
101         gc->ngpio = 8;
102         gc->direction_input = u8_gpio_dir_in;
103         gc->direction_output = u8_gpio_dir_out;
104         gc->get = u8_gpio_get;
105         gc->set = u8_gpio_set;
106 
107         ret = of_mm_gpiochip_add_data(np, mm_gc, u8_gc);
108         if (ret)
109                 goto err;
110         return 0;
111 err:
112         kfree(u8_gc);
113         return ret;
114 }
115 
116 void __init simple_gpiochip_init(const char *compatible)
117 {
118         struct device_node *np;
119 
120         for_each_compatible_node(np, NULL, compatible) {
121                 int ret;
122                 struct resource r;
123 
124                 ret = of_address_to_resource(np, 0, &r);
125                 if (ret)
126                         goto err;
127 
128                 switch (resource_size(&r)) {
129                 case 1:
130                         ret = u8_simple_gpiochip_add(np);
131                         if (ret)
132                                 goto err;
133                         break;
134                 default:
135                         /*
136                          * Whenever you need support for GPIO bank width > 1,
137                          * please just turn u8_ code into huge macros, and
138                          * construct needed uX_ code with it.
139                          */
140                         ret = -ENOSYS;
141                         goto err;
142                 }
143                 continue;
144 err:
145                 pr_err("%pOF: registration failed, status %d\n", np, ret);
146         }
147 }
148 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp