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