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  */
20 static 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 
42 static inline void mpc85xx_gpio_set_in(unsigned int gpios)
43 {
44 	mpc85xx_gpio_set(gpios, 0x00000000, 0x00000000);
45 }
46 
47 static inline void mpc85xx_gpio_set_low(unsigned int gpios)
48 {
49 	mpc85xx_gpio_set(gpios, 0xFFFFFFFF, 0x00000000);
50 }
51 
52 static inline void mpc85xx_gpio_set_high(unsigned int gpios)
53 {
54 	mpc85xx_gpio_set(gpios, 0xFFFFFFFF, 0xFFFFFFFF);
55 }
56 
57 static 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  */
69 static inline int gpio_request(unsigned gpio, const char *label)
70 {
71 	/* Compatibility shim */
72 	return 0;
73 }
74 
75 static inline int gpio_free(unsigned gpio)
76 {
77 	/* Compatibility shim */
78 	return 0;
79 }
80 
81 static inline int gpio_direction_input(unsigned gpio)
82 {
83 	mpc85xx_gpio_set_in(1U << gpio);
84 	return 0;
85 }
86 
87 static 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 
96 static inline int gpio_get_value(unsigned gpio)
97 {
98 	return !!mpc85xx_gpio_get(1U << gpio);
99 }
100 
101 static 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 
110 static 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