arch/openrisc/include/asm/gpio.h

   1 /*
   2  * OpenRISC gpio driver
   3  *
   4  * Copyright (C) 2011 Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
   5  *
   6  * based on nios2 gpio driver
   7  * Copyright (C) 2010 Thomas Chou <thomas@wytron.com.tw>
   8  *
   9  * when CONFIG_SYS_GPIO_BASE is not defined, board may provide
  10  * its own driver.
  11  *
  12  * SPDX-License-Identifier:     GPL-2.0+
  13  */
  14
  15 #ifdef CONFIG_SYS_GPIO_BASE
  16 #include <asm/io.h>
  17
  18 static inline int gpio_request(unsigned gpio, const char *label)
  19 {
  20         return 0;
  21 }
  22
  23 static inline int gpio_free(unsigned gpio)
  24 {
  25         return 0;
  26 }
  27
  28 static inline int gpio_get_value(unsigned gpio)
  29 {
  30         return (readb(CONFIG_SYS_GPIO_BASE + gpio/8) >> gpio%8) & 0x1;
  31 }
  32
  33 static inline void gpio_set_value(unsigned gpio, int value)
  34 {
  35         u8 tmp = readb(CONFIG_SYS_GPIO_BASE + gpio/8);
  36
  37         if (value)
  38                 tmp |= (1 << gpio%8);
  39         else
  40                 tmp &= ~(1 << gpio%8);
  41         writeb(tmp, CONFIG_SYS_GPIO_BASE + gpio/8);
  42 }
  43
  44 static inline int gpio_direction_input(unsigned gpio)
  45 {
  46         gpio_set_value(gpio + CONFIG_SYS_GPIO_WIDTH, 0);
  47
  48         return 0;
  49 }
  50
  51 static inline int gpio_direction_output(unsigned gpio, int value)
  52 {
  53         gpio_set_value(gpio + CONFIG_SYS_GPIO_WIDTH, 1);
  54         gpio_set_value(gpio, value);
  55
  56         return 0;
  57 }
  58
  59 static inline int gpio_is_valid(int number)
  60 {
  61         return ((unsigned)number) < CONFIG_SYS_GPIO_WIDTH;
  62 }
  63 #else
  64 extern int gpio_request(unsigned gpio, const char *label);
  65 extern int gpio_free(unsigned gpio);
  66 extern int gpio_direction_input(unsigned gpio);
  67 extern int gpio_direction_output(unsigned gpio, int value);
  68 extern int gpio_get_value(unsigned gpio);
  69 extern void gpio_set_value(unsigned gpio, int value);
  70 extern int gpio_is_valid(int number);
  71 #endif /* CONFIG_SYS_GPIO_BASE */