arch/arm/plat-s3c/include/plat/gpio-core.h

   1 /* linux/arch/arm/plat-s3c/include/plat/gpio-core.h
   2  *
   3  * Copyright 2008 Simtec Electronics
   4  *      http://armlinux.simtec.co.uk/
   5  *      Ben Dooks <ben@simtec.co.uk>
   6  *
   7  * S3C Platform - GPIO core
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12 */
  13
  14 /* Define the core gpiolib support functions that the s3c platforms may
  15  * need to extend or change depending on the hardware and the s3c chip
  16  * selected at build or found at run time.
  17  *
  18  * These definitions are not intended for driver inclusion, there is
  19  * nothing here that should not live outside the platform and core
  20  * specific code.
  21 */
  22
  23 struct s3c_gpio_chip;
  24
  25 /**
  26  * struct s3c_gpio_pm - power management (suspend/resume) information
  27  * @save: Routine to save the state of the GPIO block
  28  * @resume: Routine to resume the GPIO block.
  29  */
  30 struct s3c_gpio_pm {
  31         void (*save)(struct s3c_gpio_chip *chip);
  32         void (*resume)(struct s3c_gpio_chip *chip);
  33 };
  34
  35 struct s3c_gpio_cfg;
  36
  37 /**
  38  * struct s3c_gpio_chip - wrapper for specific implementation of gpio
  39  * @chip: The chip structure to be exported via gpiolib.
  40  * @base: The base pointer to the gpio configuration registers.
  41  * @config: special function and pull-resistor control information.
  42  * @pm_save: Save information for suspend/resume support.
  43  *
  44  * This wrapper provides the necessary information for the Samsung
  45  * specific gpios being registered with gpiolib.
  46  */
  47 struct s3c_gpio_chip {
  48         struct gpio_chip        chip;
  49         struct s3c_gpio_cfg     *config;
  50         struct s3c_gpio_pm      *pm;
  51         void __iomem            *base;
  52 #ifdef CONFIG_PM
  53         u32                     pm_save[4];
  54 #endif
  55 };
  56
  57 static inline struct s3c_gpio_chip *to_s3c_gpio(struct gpio_chip *gpc)
  58 {
  59         return container_of(gpc, struct s3c_gpio_chip, chip);
  60 }
  61
  62 /** s3c_gpiolib_add() - add the s3c specific version of a gpio_chip.
  63  * @chip: The chip to register
  64  *
  65  * This is a wrapper to gpiochip_add() that takes our specific gpio chip
  66  * information and makes the necessary alterations for the platform and
  67  * notes the information for use with the configuration systems and any
  68  * other parts of the system.
  69  */
  70 extern void s3c_gpiolib_add(struct s3c_gpio_chip *chip);
  71
  72 /* CONFIG_S3C_GPIO_TRACK enables the tracking of the s3c specific gpios
  73  * for use with the configuration calls, and other parts of the s3c gpiolib
  74  * support code.
  75  *
  76  * Not all s3c support code will need this, as some configurations of cpu
  77  * may only support one or two different configuration options and have an
  78  * easy gpio to s3c_gpio_chip mapping function. If this is the case, then
  79  * the machine support file should provide its own s3c_gpiolib_getchip()
  80  * and any other necessary functions.
  81  */
  82
  83 #ifdef CONFIG_S3C_GPIO_TRACK
  84 extern struct s3c_gpio_chip *s3c_gpios[S3C_GPIO_END];
  85
  86 static inline struct s3c_gpio_chip *s3c_gpiolib_getchip(unsigned int chip)
  87 {
  88         return (chip < S3C_GPIO_END) ? s3c_gpios[chip] : NULL;
  89 }
  90 #else
  91 /* machine specific code should provide s3c_gpiolib_getchip */
  92
  93 static inline void s3c_gpiolib_track(struct s3c_gpio_chip *chip) { }
  94 #endif
  95
  96 #ifdef CONFIG_PM
  97 extern struct s3c_gpio_pm s3c_gpio_pm_1bit;
  98 extern struct s3c_gpio_pm s3c_gpio_pm_2bit;
  99 extern struct s3c_gpio_pm s3c_gpio_pm_4bit;
 100 #define __gpio_pm(x) x
 101 #else
 102 #define s3c_gpio_pm_1bit NULL
 103 #define s3c_gpio_pm_2bit NULL
 104 #define s3c_gpio_pm_4bit NULL
 105 #define __gpio_pm(x) NULL
 106
 107 #endif /* CONFIG_PM */