2 * Copyright (c) 2011 The Chromium OS Authors.
3 * SPDX-License-Identifier: GPL-2.0+
9 /* Flags for each GPIO */
10 #define GPIOF_OUTPUT (1 << 0) /* Currently set as an output */
11 #define GPIOF_HIGH (1 << 1) /* Currently set high */
12 #define GPIOF_RESERVED (1 << 2) /* Is in use / requested */
15 const char *label
; /* label given by requester */
16 u8 flags
; /* flags (GPIOF_...) */
21 * TODO: Put this into sandbox state
23 static struct gpio_state state
[CONFIG_SANDBOX_GPIO_COUNT
];
25 /* Access routines for GPIO state */
26 static u8
*get_gpio_flags(unsigned gp
)
28 /* assert()'s could be disabled, so make sure we handle that */
29 assert(gp
< ARRAY_SIZE(state
));
30 if (gp
>= ARRAY_SIZE(state
)) {
31 static u8 invalid_flags
;
32 printf("sandbox_gpio: error: invalid gpio %u\n", gp
);
33 return &invalid_flags
;
36 return &state
[gp
].flags
;
39 static int get_gpio_flag(unsigned gp
, int flag
)
41 return (*get_gpio_flags(gp
) & flag
) != 0;
44 static int set_gpio_flag(unsigned gp
, int flag
, int value
)
46 u8
*gpio
= get_gpio_flags(gp
);
56 static int check_reserved(unsigned gpio
, const char *func
)
58 if (!get_gpio_flag(gpio
, GPIOF_RESERVED
)) {
59 printf("sandbox_gpio: %s: error: gpio %u not reserved\n",
68 * Back-channel sandbox-internal-only access to GPIO state
71 int sandbox_gpio_get_value(unsigned gp
)
73 if (get_gpio_flag(gp
, GPIOF_OUTPUT
))
74 debug("sandbox_gpio: get_value on output gpio %u\n", gp
);
75 return get_gpio_flag(gp
, GPIOF_HIGH
);
78 int sandbox_gpio_set_value(unsigned gp
, int value
)
80 return set_gpio_flag(gp
, GPIOF_HIGH
, value
);
83 int sandbox_gpio_get_direction(unsigned gp
)
85 return get_gpio_flag(gp
, GPIOF_OUTPUT
);
88 int sandbox_gpio_set_direction(unsigned gp
, int output
)
90 return set_gpio_flag(gp
, GPIOF_OUTPUT
, output
);
94 * These functions implement the public interface within U-Boot
97 /* set GPIO port 'gp' as an input */
98 int gpio_direction_input(unsigned gp
)
100 debug("%s: gp:%u\n", __func__
, gp
);
102 if (check_reserved(gp
, __func__
))
105 return sandbox_gpio_set_direction(gp
, 0);
108 /* set GPIO port 'gp' as an output, with polarity 'value' */
109 int gpio_direction_output(unsigned gp
, int value
)
111 debug("%s: gp:%u, value = %d\n", __func__
, gp
, value
);
113 if (check_reserved(gp
, __func__
))
116 return sandbox_gpio_set_direction(gp
, 1) |
117 sandbox_gpio_set_value(gp
, value
);
120 /* read GPIO IN value of port 'gp' */
121 int gpio_get_value(unsigned gp
)
123 debug("%s: gp:%u\n", __func__
, gp
);
125 if (check_reserved(gp
, __func__
))
128 return sandbox_gpio_get_value(gp
);
131 /* write GPIO OUT value to port 'gp' */
132 int gpio_set_value(unsigned gp
, int value
)
134 debug("%s: gp:%u, value = %d\n", __func__
, gp
, value
);
136 if (check_reserved(gp
, __func__
))
139 if (!sandbox_gpio_get_direction(gp
)) {
140 printf("sandbox_gpio: error: set_value on input gpio %u\n", gp
);
144 return sandbox_gpio_set_value(gp
, value
);
147 int gpio_request(unsigned gp
, const char *label
)
149 debug("%s: gp:%u, label:%s\n", __func__
, gp
, label
);
151 if (gp
>= ARRAY_SIZE(state
)) {
152 printf("sandbox_gpio: error: invalid gpio %u\n", gp
);
156 if (get_gpio_flag(gp
, GPIOF_RESERVED
)) {
157 printf("sandbox_gpio: error: gpio %u already reserved\n", gp
);
161 state
[gp
].label
= label
;
162 return set_gpio_flag(gp
, GPIOF_RESERVED
, 1);
165 int gpio_free(unsigned gp
)
167 debug("%s: gp:%u\n", __func__
, gp
);
169 if (check_reserved(gp
, __func__
))
172 state
[gp
].label
= NULL
;
173 return set_gpio_flag(gp
, GPIOF_RESERVED
, 0);
176 /* Display GPIO information */
181 puts("Sandbox GPIOs\n");
183 for (gpio
= 0; gpio
< ARRAY_SIZE(state
); ++gpio
) {
184 const char *label
= state
[gpio
].label
;
186 printf("%4d: %s: %d [%c] %s\n",
188 sandbox_gpio_get_direction(gpio
) ? "out" : " in",
189 sandbox_gpio_get_value(gpio
),
190 get_gpio_flag(gpio
, GPIOF_RESERVED
) ? 'x' : ' ',