1 /* linux/arch/arm/plat-s3c/include/plat/gpio-cfg.h
2 *
3 * Copyright 2008 Openmoko, Inc.
4 * Copyright 2008 Simtec Electronics
5 * http://armlinux.simtec.co.uk/
6 * Ben Dooks <ben@simtec.co.uk>
7 *
8 * S3C Platform - GPIO pin configuration
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
13 */
14
15 /* This file contains the necessary definitions to get the basic gpio
16 * pin configuration done such as setting a pin to input or output or
17 * changing the pull-{up,down} configurations.
18 */
19
20 /* Note, this interface is being added to the s3c64xx arch first and will
21 * be added to the s3c24xx systems later.
22 */
23
24 #ifndef __PLAT_GPIO_CFG_H
25 #define __PLAT_GPIO_CFG_H __FILE__
26
27 #include<linux/types.h>
28
29 typedef unsigned int __bitwise__ samsung_gpio_pull_t;
30 typedef unsigned int __bitwise__ s5p_gpio_drvstr_t;
31
32 /* forward declaration if gpio-core.h hasn't been included */
33 struct samsung_gpio_chip;
34
35 /**
36 * struct samsung_gpio_cfg GPIO configuration
37 * @cfg_eint: Configuration setting when used for external interrupt source
38 * @get_pull: Read the current pull configuration for the GPIO
39 * @set_pull: Set the current pull configuraiton for the GPIO
40 * @set_config: Set the current configuration for the GPIO
41 * @get_config: Read the current configuration for the GPIO
42 *
43 * Each chip can have more than one type of GPIO bank available and some
44 * have different capabilites even when they have the same control register
45 * layouts. Provide an point to vector control routine and provide any
46 * per-bank configuration information that other systems such as the
47 * external interrupt code will need.
48 *
49 * @sa samsung_gpio_cfgpin
50 * @sa s3c_gpio_getcfg
51 * @sa s3c_gpio_setpull
52 * @sa s3c_gpio_getpull
53 */
54 struct samsung_gpio_cfg {
55 unsigned int cfg_eint;
56
57 samsung_gpio_pull_t (*get_pull)(struct samsung_gpio_chip *chip, unsigned offs);
58 int (*set_pull)(struct samsung_gpio_chip *chip, unsigned offs,
59 samsung_gpio_pull_t pull);
60
61 unsigned (*get_config)(struct samsung_gpio_chip *chip, unsigned offs);
62 int (*set_config)(struct samsung_gpio_chip *chip, unsigned offs,
63 unsigned config);
64 };
65
66 #define S3C_GPIO_SPECIAL_MARK (0xfffffff0)
67 #define S3C_GPIO_SPECIAL(x) (S3C_GPIO_SPECIAL_MARK | (x))
68
69 /* Defines for generic pin configurations */
70 #define S3C_GPIO_INPUT (S3C_GPIO_SPECIAL(0))
71 #define S3C_GPIO_OUTPUT (S3C_GPIO_SPECIAL(1))
72 #define S3C_GPIO_SFN(x) (S3C_GPIO_SPECIAL(x))
73
74 #define samsung_gpio_is_cfg_special(_cfg) \
75 (((_cfg) & S3C_GPIO_SPECIAL_MARK) == S3C_GPIO_SPECIAL_MARK)
76
77 /**
78 * s3c_gpio_cfgpin() - Change the GPIO function of a pin.
79 * @pin pin The pin number to configure.
80 * @to to The configuration for the pin's function.
81 *
82 * Configure which function is actually connected to the external
83 * pin, such as an gpio input, output or some form of special function
84 * connected to an internal peripheral block.
85 *
86 * The @to parameter can be one of the generic S3C_GPIO_INPUT, S3C_GPIO_OUTPUT
87 * or S3C_GPIO_SFN() to indicate one of the possible values that the helper
88 * will then generate the correct bit mask and shift for the configuration.
89 *
90 * If a bank of GPIOs all needs to be set to special-function 2, then
91 * the following code will work:
92 *
93 * for (gpio = start; gpio < end; gpio++)
94 * s3c_gpio_cfgpin(gpio, S3C_GPIO_SFN(2));
95 *
96 * The @to parameter can also be a specific value already shifted to the
97 * correct position in the control register, although these are discouraged
98 * in newer kernels and are only being kept for compatibility.
99 */
100 extern int s3c_gpio_cfgpin(unsigned int pin, unsigned int to);
101
102 /**
103 * s3c_gpio_getcfg - Read the current function for a GPIO pin
104 * @pin: The pin to read the configuration value for.
105 *
106 * Read the configuration state of the given @pin, returning a value that
107 * could be passed back to s3c_gpio_cfgpin().
108 *
109 * @sa s3c_gpio_cfgpin
110 */
111 extern unsigned s3c_gpio_getcfg(unsigned int pin);
112
113 /**
114 * s3c_gpio_cfgpin_range() - Change the GPIO function for configuring pin range
115 * @start: The pin number to start at
116 * @nr: The number of pins to configure from @start.
117 * @cfg: The configuration for the pin's function
118 *
119 * Call s3c_gpio_cfgpin() for the @nr pins starting at @start.
120 *
121 * @sa s3c_gpio_cfgpin.
122 */
123 extern int s3c_gpio_cfgpin_range(unsigned int start, unsigned int nr,
124 unsigned int cfg);
125
126 /* Define values for the pull-{up,down} available for each gpio pin.
127 *
128 * These values control the state of the weak pull-{up,down} resistors
129 * available on most pins on the S3C series. Not all chips support both
130 * up or down settings, and it may be dependent on the chip that is being
131 * used to whether the particular mode is available.
132 */
133 #define S3C_GPIO_PULL_NONE ((__force samsung_gpio_pull_t)0x00)
134 #define S3C_GPIO_PULL_DOWN ((__force samsung_gpio_pull_t)0x01)
135 #define S3C_GPIO_PULL_UP ((__force samsung_gpio_pull_t)0x02)
136
137 /**
138 * s3c_gpio_setpull() - set the state of a gpio pin pull resistor
139 * @pin: The pin number to configure the pull resistor.
140 * @pull: The configuration for the pull resistor.
141 *
142 * This function sets the state of the pull-{up,down} resistor for the
143 * specified pin. It will return 0 if successful, or a negative error
144 * code if the pin cannot support the requested pull setting.
145 *
146 * @pull is one of S3C_GPIO_PULL_NONE, S3C_GPIO_PULL_DOWN or S3C_GPIO_PULL_UP.
147 */
148 extern int s3c_gpio_setpull(unsigned int pin, samsung_gpio_pull_t pull);
149
150 /**
151 * s3c_gpio_getpull() - get the pull resistor state of a gpio pin
152 * @pin: The pin number to get the settings for
153 *
154 * Read the pull resistor value for the specified pin.
155 */
156 extern samsung_gpio_pull_t s3c_gpio_getpull(unsigned int pin);
157
158 /* configure `all` aspects of an gpio */
159
160 /**
161 * s3c_gpio_cfgall_range() - configure range of gpio functtion and pull.
162 * @start: The gpio number to start at.
163 * @nr: The number of gpio to configure from @start.
164 * @cfg: The configuration to use
165 * @pull: The pull setting to use.
166 *
167 * Run s3c_gpio_cfgpin() and s3c_gpio_setpull() over the gpio range starting
168 * @gpio and running for @size.
169 *
170 * @sa s3c_gpio_cfgpin
171 * @sa s3c_gpio_setpull
172 * @sa s3c_gpio_cfgpin_range
173 */
174 extern int s3c_gpio_cfgall_range(unsigned int start, unsigned int nr,
175 unsigned int cfg, samsung_gpio_pull_t pull);
176
s3c_gpio_cfgrange_nopull(unsigned int pin,unsigned int size,unsigned int cfg)177 static inline int s3c_gpio_cfgrange_nopull(unsigned int pin, unsigned int size,
178 unsigned int cfg)
179 {
180 return s3c_gpio_cfgall_range(pin, size, cfg, S3C_GPIO_PULL_NONE);
181 }
182
183 /* Define values for the drvstr available for each gpio pin.
184 *
185 * These values control the value of the output signal driver strength,
186 * configurable on most pins on the S5P series.
187 */
188 #define S5P_GPIO_DRVSTR_LV1 ((__force s5p_gpio_drvstr_t)0x0)
189 #define S5P_GPIO_DRVSTR_LV2 ((__force s5p_gpio_drvstr_t)0x2)
190 #define S5P_GPIO_DRVSTR_LV3 ((__force s5p_gpio_drvstr_t)0x1)
191 #define S5P_GPIO_DRVSTR_LV4 ((__force s5p_gpio_drvstr_t)0x3)
192
193 /**
194 * s5c_gpio_get_drvstr() - get the driver streght value of a gpio pin
195 * @pin: The pin number to get the settings for
196 *
197 * Read the driver streght value for the specified pin.
198 */
199 extern s5p_gpio_drvstr_t s5p_gpio_get_drvstr(unsigned int pin);
200
201 /**
202 * s3c_gpio_set_drvstr() - set the driver streght value of a gpio pin
203 * @pin: The pin number to configure the driver streght value
204 * @drvstr: The new value of the driver strength
205 *
206 * This function sets the driver strength value for the specified pin.
207 * It will return 0 if successful, or a negative error code if the pin
208 * cannot support the requested setting.
209 */
210 extern int s5p_gpio_set_drvstr(unsigned int pin, s5p_gpio_drvstr_t drvstr);
211
212 /**
213 * s5p_register_gpio_interrupt() - register interrupt support for a gpio group
214 * @pin: The pin number from the group to be registered
215 *
216 * This function registers gpio interrupt support for the group that the
217 * specified pin belongs to.
218 *
219 * The total number of gpio pins is quite large ob s5p series. Registering
220 * irq support for all of them would be a resource waste. Because of that the
221 * interrupt support for standard gpio pins is registered dynamically.
222 *
223 * It will return the irq number of the interrupt that has been registered
224 * or -ENOMEM if no more gpio interrupts can be registered. It is allowed
225 * to call this function more than once for the same gpio group (the group
226 * will be registered only once).
227 */
228 extern int s5p_register_gpio_interrupt(int pin);
229
230 /** s5p_register_gpioint_bank() - add gpio bank for further gpio interrupt
231 * registration (see s5p_register_gpio_interrupt function)
232 * @chain_irq: chained irq number for the gpio int handler for this bank
233 * @start: start gpio group number of this bank
234 * @nr_groups: number of gpio groups handled by this bank
235 *
236 * This functions registers initial information about gpio banks that
237 * can be later used by the s5p_register_gpio_interrupt() function to
238 * enable support for gpio interrupt for particular gpio group.
239 */
240 #ifdef CONFIG_S5P_GPIO_INT
241 extern int s5p_register_gpioint_bank(int chain_irq, int start, int nr_groups);
242 #else
243 #define s5p_register_gpioint_bank(chain_irq, start, nr_groups) do { } while (0)
244 #endif
245
246 #endif /* __PLAT_GPIO_CFG_H */
247