1 /*
2 * TI DaVinci GPIO Support
3 *
4 * Copyright (c) 2006 David Brownell
5 * Copyright (c) 2007, MontaVista Software, Inc. <source@mvista.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 */
12
13 #ifndef __DAVINCI_GPIO_H
14 #define __DAVINCI_GPIO_H
15
16 #include <asm-generic/gpio.h>
17
18 #define __ARM_GPIOLIB_COMPLEX
19
20 /* The inline versions use the static inlines in the driver header */
21 #include "gpio-davinci.h"
22
23 /*
24 * The get/set/clear functions will inline when called with constant
25 * parameters referencing built-in GPIOs, for low-overhead bitbanging.
26 *
27 * gpio_set_value() will inline only on traditional Davinci style controllers
28 * with distinct set/clear registers.
29 *
30 * Otherwise, calls with variable parameters or referencing external
31 * GPIOs (e.g. on GPIO expander chips) use outlined functions.
32 */
gpio_set_value(unsigned gpio,int value)33 static inline void gpio_set_value(unsigned gpio, int value)
34 {
35 if (__builtin_constant_p(value) && gpio < davinci_soc_info.gpio_num) {
36 struct davinci_gpio_controller *ctlr;
37 u32 mask;
38
39 ctlr = __gpio_to_controller(gpio);
40
41 if (ctlr->set_data != ctlr->clr_data) {
42 mask = __gpio_mask(gpio);
43 if (value)
44 __raw_writel(mask, ctlr->set_data);
45 else
46 __raw_writel(mask, ctlr->clr_data);
47 return;
48 }
49 }
50
51 __gpio_set_value(gpio, value);
52 }
53
54 /* Returns zero or nonzero; works for gpios configured as inputs OR
55 * as outputs, at least for built-in GPIOs.
56 *
57 * NOTE: for built-in GPIOs, changes in reported values are synchronized
58 * to the GPIO clock. This is easily seen after calling gpio_set_value()
59 * and then immediately gpio_get_value(), where the gpio_get_value() will
60 * return the old value until the GPIO clock ticks and the new value gets
61 * latched.
62 */
gpio_get_value(unsigned gpio)63 static inline int gpio_get_value(unsigned gpio)
64 {
65 struct davinci_gpio_controller *ctlr;
66
67 if (!__builtin_constant_p(gpio) || gpio >= davinci_soc_info.gpio_num)
68 return __gpio_get_value(gpio);
69
70 ctlr = __gpio_to_controller(gpio);
71 return __gpio_mask(gpio) & __raw_readl(ctlr->in_data);
72 }
73
gpio_cansleep(unsigned gpio)74 static inline int gpio_cansleep(unsigned gpio)
75 {
76 if (__builtin_constant_p(gpio) && gpio < davinci_soc_info.gpio_num)
77 return 0;
78 else
79 return __gpio_cansleep(gpio);
80 }
81
irq_to_gpio(unsigned irq)82 static inline int irq_to_gpio(unsigned irq)
83 {
84 /* don't support the reverse mapping */
85 return -ENOSYS;
86 }
87
88 #endif /* __DAVINCI_GPIO_H */
89