LXR uboot/arch/powerpc/include/asm/mpc85xx

   1/*
   2 * Copyright 2010 eXMeritus, A Boeing Company
   3 *
   4 * SPDX-License-Identifier:     GPL-2.0+
   5 */
   6
   7#ifndef POWERPC_ASM_MPC85XX_GPIO_H_
   8#define POWERPC_ASM_MPC85XX_GPIO_H_
   9
  10# include <asm/immap_85xx.h>
  11
  12/*
  13 * The following internal functions are an MPC85XX-specific GPIO API which
  14 * allows setting and querying multiple GPIOs in a single operation.
  15 *
  16 * All of these look relatively large, but the arguments are almost always
  17 * constants, so they compile down to just a few instructions and a
  18 * memory-mapped IO operation or two.
  19 */
  20static inline void mpc85xx_gpio_set(unsigned int mask,
  21                unsigned int dir, unsigned int val)
  22{
  23        ccsr_gpio_t *gpio = (void *)(CONFIG_SYS_MPC85xx_GPIO_ADDR);
  24
  25        /* First mask off the unwanted parts of "dir" and "val" */
  26        dir &= mask;
  27        val &= mask;
  28
  29        /* Now read in the values we're supposed to preserve */
  30        dir |= (in_be32(&gpio->gpdir) & ~mask);
  31        val |= (in_be32(&gpio->gpdat) & ~mask);
  32
  33        /*
  34         * Poke the new output values first, then set the direction.  This
  35         * helps to avoid transient data when switching from input to output
  36         * and vice versa.
  37         */
  38        out_be32(&gpio->gpdat, val);
  39        out_be32(&gpio->gpdir, dir);
  40}
  41
  42static inline void mpc85xx_gpio_set_in(unsigned int gpios)
  43{
  44        mpc85xx_gpio_set(gpios, 0x00000000, 0x00000000);
  45}
  46
  47static inline void mpc85xx_gpio_set_low(unsigned int gpios)
  48{
  49        mpc85xx_gpio_set(gpios, 0xFFFFFFFF, 0x00000000);
  50}
  51
  52static inline void mpc85xx_gpio_set_high(unsigned int gpios)
  53{
  54        mpc85xx_gpio_set(gpios, 0xFFFFFFFF, 0xFFFFFFFF);
  55}
  56
  57static inline unsigned int mpc85xx_gpio_get(unsigned int mask)
  58{
  59        ccsr_gpio_t *gpio = (void *)(CONFIG_SYS_MPC85xx_GPIO_ADDR);
  60
  61        /* Read the requested values */
  62        return in_be32(&gpio->gpdat) & mask;
  63}
  64
  65/*
  66 * These implement the generic Linux GPIO API on top of the other functions
  67 * in this header.
  68 */
  69static inline int gpio_request(unsigned gpio, const char *label)
  70{
  71        /* Compatibility shim */
  72        return 0;
  73}
  74
  75static inline int gpio_free(unsigned gpio)
  76{
  77        /* Compatibility shim */
  78        return 0;
  79}
  80
  81static inline int gpio_direction_input(unsigned gpio)
  82{
  83        mpc85xx_gpio_set_in(1U << gpio);
  84        return 0;
  85}
  86
  87static inline int gpio_direction_output(unsigned gpio, int value)
  88{
  89        if (value)
  90                mpc85xx_gpio_set_high(1U << gpio);
  91        else
  92                mpc85xx_gpio_set_low(1U << gpio);
  93        return 0;
  94}
  95
  96static inline int gpio_get_value(unsigned gpio)
  97{
  98        return !!mpc85xx_gpio_get(1U << gpio);
  99}
 100
 101static inline int gpio_set_value(unsigned gpio, int value)
 102{
 103        if (value)
 104                mpc85xx_gpio_set_high(1U << gpio);
 105        else
 106                mpc85xx_gpio_set_low(1U << gpio);
 107        return 0;
 108}
 109
 110static inline int gpio_is_valid(int gpio)
 111{
 112        return (gpio >= 0) && (gpio < 32);
 113}
 114
 115#endif /* not POWERPC_ASM_MPC85XX_GPIO_H_ */
 116