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  */
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 
41 static inline void mpc85xx_gpio_set_in(unsigned int gpios)
42 {
43 	mpc85xx_gpio_set(gpios, 0x00000000, 0x00000000);
44 }
45 
46 static inline void mpc85xx_gpio_set_low(unsigned int gpios)
47 {
48 	mpc85xx_gpio_set(gpios, 0xFFFFFFFF, 0x00000000);
49 }
50 
51 static inline void mpc85xx_gpio_set_high(unsigned int gpios)
52 {
53 	mpc85xx_gpio_set(gpios, 0xFFFFFFFF, 0xFFFFFFFF);
54 }
55 
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  */
68 static inline int gpio_request(unsigned gpio, const char *label)
69 {
70 	/* Compatibility shim */
71 	return 0;
72 }
73 
74 static inline int gpio_free(unsigned gpio)
75 {
76 	/* Compatibility shim */
77 	return 0;
78 }
79 
80 static inline int gpio_direction_input(unsigned gpio)
81 {
82 	mpc85xx_gpio_set_in(1U << gpio);
83 	return 0;
84 }
85 
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 
95 static inline int gpio_get_value(unsigned gpio)
96 {
97 	return !!mpc85xx_gpio_get(1U << gpio);
98 }
99 
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 
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