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git.ipfire.org Git - people/ms/u-boot.git/blob - drivers/gpio/tegra_gpio.c
2 * NVIDIA Tegra20 GPIO handling.
3 * (C) Copyright 2010-2012
4 * NVIDIA Corporation <www.nvidia.com>
6 * See file CREDITS for list of people who contributed to this
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation; either version 2 of
12 * the License, or (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
26 * Based on (mostly copied from) kw_gpio.c based Linux 2.6 kernel driver.
27 * Tom Warren (twarren@nvidia.com)
32 #include <asm/bitops.h>
33 #include <asm/arch/tegra20.h>
43 static struct gpio_names
{
44 char name
[GPIO_NAME_SIZE
];
45 } gpio_names
[MAX_NUM_GPIOS
];
47 static char *get_name(int i
)
49 return *gpio_names
[i
].name
? gpio_names
[i
].name
: "UNKNOWN";
52 /* Return config of pin 'gpio' as GPIO (1) or SFPIO (0) */
53 static int get_config(unsigned gpio
)
55 struct gpio_ctlr
*ctlr
= (struct gpio_ctlr
*)NV_PA_GPIO_BASE
;
56 struct gpio_ctlr_bank
*bank
= &ctlr
->gpio_bank
[GPIO_BANK(gpio
)];
60 u
= readl(&bank
->gpio_config
[GPIO_PORT(gpio
)]);
61 type
= (u
>> GPIO_BIT(gpio
)) & 1;
63 debug("get_config: port = %d, bit = %d is %s\n",
64 GPIO_FULLPORT(gpio
), GPIO_BIT(gpio
), type
? "GPIO" : "SFPIO");
69 /* Config pin 'gpio' as GPIO or SFPIO, based on 'type' */
70 static void set_config(unsigned gpio
, int type
)
72 struct gpio_ctlr
*ctlr
= (struct gpio_ctlr
*)NV_PA_GPIO_BASE
;
73 struct gpio_ctlr_bank
*bank
= &ctlr
->gpio_bank
[GPIO_BANK(gpio
)];
76 debug("set_config: port = %d, bit = %d, %s\n",
77 GPIO_FULLPORT(gpio
), GPIO_BIT(gpio
), type
? "GPIO" : "SFPIO");
79 u
= readl(&bank
->gpio_config
[GPIO_PORT(gpio
)]);
81 u
|= 1 << GPIO_BIT(gpio
);
83 u
&= ~(1 << GPIO_BIT(gpio
));
84 writel(u
, &bank
->gpio_config
[GPIO_PORT(gpio
)]);
87 /* Return GPIO pin 'gpio' direction - 0 = input or 1 = output */
88 static int get_direction(unsigned gpio
)
90 struct gpio_ctlr
*ctlr
= (struct gpio_ctlr
*)NV_PA_GPIO_BASE
;
91 struct gpio_ctlr_bank
*bank
= &ctlr
->gpio_bank
[GPIO_BANK(gpio
)];
95 u
= readl(&bank
->gpio_dir_out
[GPIO_PORT(gpio
)]);
96 dir
= (u
>> GPIO_BIT(gpio
)) & 1;
98 debug("get_direction: port = %d, bit = %d, %s\n",
99 GPIO_FULLPORT(gpio
), GPIO_BIT(gpio
), dir
? "OUT" : "IN");
104 /* Config GPIO pin 'gpio' as input or output (OE) as per 'output' */
105 static void set_direction(unsigned gpio
, int output
)
107 struct gpio_ctlr
*ctlr
= (struct gpio_ctlr
*)NV_PA_GPIO_BASE
;
108 struct gpio_ctlr_bank
*bank
= &ctlr
->gpio_bank
[GPIO_BANK(gpio
)];
111 debug("set_direction: port = %d, bit = %d, %s\n",
112 GPIO_FULLPORT(gpio
), GPIO_BIT(gpio
), output
? "OUT" : "IN");
114 u
= readl(&bank
->gpio_dir_out
[GPIO_PORT(gpio
)]);
116 u
|= 1 << GPIO_BIT(gpio
);
118 u
&= ~(1 << GPIO_BIT(gpio
));
119 writel(u
, &bank
->gpio_dir_out
[GPIO_PORT(gpio
)]);
122 /* set GPIO pin 'gpio' output bit as 0 or 1 as per 'high' */
123 static void set_level(unsigned gpio
, int high
)
125 struct gpio_ctlr
*ctlr
= (struct gpio_ctlr
*)NV_PA_GPIO_BASE
;
126 struct gpio_ctlr_bank
*bank
= &ctlr
->gpio_bank
[GPIO_BANK(gpio
)];
129 debug("set_level: port = %d, bit %d == %d\n",
130 GPIO_FULLPORT(gpio
), GPIO_BIT(gpio
), high
);
132 u
= readl(&bank
->gpio_out
[GPIO_PORT(gpio
)]);
134 u
|= 1 << GPIO_BIT(gpio
);
136 u
&= ~(1 << GPIO_BIT(gpio
));
137 writel(u
, &bank
->gpio_out
[GPIO_PORT(gpio
)]);
141 * Generic_GPIO primitives.
144 int gpio_request(unsigned gpio
, const char *label
)
146 if (gpio
>= MAX_NUM_GPIOS
)
150 strncpy(gpio_names
[gpio
].name
, label
, GPIO_NAME_SIZE
);
151 gpio_names
[gpio
].name
[GPIO_NAME_SIZE
- 1] = '\0';
154 /* Configure as a GPIO */
160 int gpio_free(unsigned gpio
)
162 if (gpio
>= MAX_NUM_GPIOS
)
165 gpio_names
[gpio
].name
[0] = '\0';
166 /* Do not configure as input or change pin mux here */
170 /* read GPIO OUT value of pin 'gpio' */
171 static int gpio_get_output_value(unsigned gpio
)
173 struct gpio_ctlr
*ctlr
= (struct gpio_ctlr
*)NV_PA_GPIO_BASE
;
174 struct gpio_ctlr_bank
*bank
= &ctlr
->gpio_bank
[GPIO_BANK(gpio
)];
177 debug("gpio_get_output_value: pin = %d (port %d:bit %d)\n",
178 gpio
, GPIO_FULLPORT(gpio
), GPIO_BIT(gpio
));
180 val
= readl(&bank
->gpio_out
[GPIO_PORT(gpio
)]);
182 return (val
>> GPIO_BIT(gpio
)) & 1;
185 /* set GPIO pin 'gpio' as an input */
186 int gpio_direction_input(unsigned gpio
)
188 debug("gpio_direction_input: pin = %d (port %d:bit %d)\n",
189 gpio
, GPIO_FULLPORT(gpio
), GPIO_BIT(gpio
));
191 /* Configure GPIO direction as input. */
192 set_direction(gpio
, 0);
197 /* set GPIO pin 'gpio' as an output, with polarity 'value' */
198 int gpio_direction_output(unsigned gpio
, int value
)
200 debug("gpio_direction_output: pin = %d (port %d:bit %d) = %s\n",
201 gpio
, GPIO_FULLPORT(gpio
), GPIO_BIT(gpio
),
202 value
? "HIGH" : "LOW");
204 /* Configure GPIO output value. */
205 set_level(gpio
, value
);
207 /* Configure GPIO direction as output. */
208 set_direction(gpio
, 1);
213 /* read GPIO IN value of pin 'gpio' */
214 int gpio_get_value(unsigned gpio
)
216 struct gpio_ctlr
*ctlr
= (struct gpio_ctlr
*)NV_PA_GPIO_BASE
;
217 struct gpio_ctlr_bank
*bank
= &ctlr
->gpio_bank
[GPIO_BANK(gpio
)];
220 debug("gpio_get_value: pin = %d (port %d:bit %d)\n",
221 gpio
, GPIO_FULLPORT(gpio
), GPIO_BIT(gpio
));
223 val
= readl(&bank
->gpio_in
[GPIO_PORT(gpio
)]);
225 return (val
>> GPIO_BIT(gpio
)) & 1;
228 /* write GPIO OUT value to pin 'gpio' */
229 int gpio_set_value(unsigned gpio
, int value
)
231 debug("gpio_set_value: pin = %d (port %d:bit %d), value = %d\n",
232 gpio
, GPIO_FULLPORT(gpio
), GPIO_BIT(gpio
), value
);
234 /* Configure GPIO output value. */
235 set_level(gpio
, value
);
241 * Display Tegra GPIO information
248 for (c
= 0; c
< MAX_NUM_GPIOS
; c
++) {
249 type
= get_config(c
); /* GPIO, not SFPIO */
251 printf("GPIO_%d:\t%s is an %s, ", c
,
253 get_direction(c
) ? "OUTPUT" : "INPUT");
254 if (get_direction(c
))
255 printf("value = %d", gpio_get_output_value(c
));
257 printf("value = %d", gpio_get_value(c
));