1 /*
2 * ADI GPIO2 Abstraction Layer
3 * Support BF54x, BF60x and future processors.
4 *
5 * Copyright 2008-2013 Analog Devices Inc.
6 *
7 * Licensed under the GPL-2 or later
8 */
9
10 #include <common.h>
11 #include <malloc.h>
12 #include <linux/bug.h>
13 #include <linux/errno.h>
14 #include <asm/gpio.h>
15
16 #define RESOURCE_LABEL_SIZE 16
17
18 static struct str_ident {
19 char name[RESOURCE_LABEL_SIZE];
20 } str_ident[MAX_RESOURCES];
21
gpio_error(unsigned gpio)22 static void gpio_error(unsigned gpio)
23 {
24 printf("adi_gpio2: GPIO %d wasn't requested!\n", gpio);
25 }
26
set_label(unsigned short ident,const char * label)27 static void set_label(unsigned short ident, const char *label)
28 {
29 if (label) {
30 strncpy(str_ident[ident].name, label,
31 RESOURCE_LABEL_SIZE);
32 str_ident[ident].name[RESOURCE_LABEL_SIZE - 1] = 0;
33 }
34 }
35
get_label(unsigned short ident)36 static char *get_label(unsigned short ident)
37 {
38 return *str_ident[ident].name ? str_ident[ident].name : "UNKNOWN";
39 }
40
cmp_label(unsigned short ident,const char * label)41 static int cmp_label(unsigned short ident, const char *label)
42 {
43 if (label == NULL)
44 printf("adi_gpio2: please provide none-null label\n");
45
46 if (label)
47 return strcmp(str_ident[ident].name, label);
48 else
49 return -EINVAL;
50 }
51
52 #define map_entry(m, i) reserved_##m##_map[gpio_bank(i)]
53 #define is_reserved(m, i, e) (map_entry(m, i) & gpio_bit(i))
54 #define reserve(m, i) (map_entry(m, i) |= gpio_bit(i))
55 #define unreserve(m, i) (map_entry(m, i) &= ~gpio_bit(i))
56 #define DECLARE_RESERVED_MAP(m, c) unsigned short reserved_##m##_map[c]
57
58 static DECLARE_RESERVED_MAP(gpio, GPIO_BANK_NUM);
59 static DECLARE_RESERVED_MAP(peri, gpio_bank(MAX_RESOURCES));
60
check_gpio(unsigned gpio)61 inline int check_gpio(unsigned gpio)
62 {
63 #if defined(CONFIG_BF54x)
64 if (gpio == GPIO_PB15 || gpio == GPIO_PC14 || gpio == GPIO_PC15 ||
65 gpio == GPIO_PH14 || gpio == GPIO_PH15 ||
66 gpio == GPIO_PJ14 || gpio == GPIO_PJ15)
67 return -EINVAL;
68 #endif
69 if (gpio >= MAX_GPIOS)
70 return -EINVAL;
71 return 0;
72 }
73
port_setup(unsigned gpio,unsigned short usage)74 static void port_setup(unsigned gpio, unsigned short usage)
75 {
76 #if defined(CONFIG_BF54x)
77 if (usage == GPIO_USAGE)
78 gpio_array[gpio_bank(gpio)]->port_fer &= ~gpio_bit(gpio);
79 else
80 gpio_array[gpio_bank(gpio)]->port_fer |= gpio_bit(gpio);
81 #else
82 if (usage == GPIO_USAGE)
83 gpio_array[gpio_bank(gpio)]->port_fer_clear = gpio_bit(gpio);
84 else
85 gpio_array[gpio_bank(gpio)]->port_fer_set = gpio_bit(gpio);
86 #endif
87 }
88
portmux_setup(unsigned short per)89 inline void portmux_setup(unsigned short per)
90 {
91 u32 pmux;
92 u16 ident = P_IDENT(per);
93 u16 function = P_FUNCT2MUX(per);
94
95 pmux = gpio_array[gpio_bank(ident)]->port_mux;
96
97 pmux &= ~(0x3 << (2 * gpio_sub_n(ident)));
98 pmux |= (function & 0x3) << (2 * gpio_sub_n(ident));
99
100 gpio_array[gpio_bank(ident)]->port_mux = pmux;
101 }
102
get_portmux(unsigned short per)103 inline u16 get_portmux(unsigned short per)
104 {
105 u32 pmux;
106 u16 ident = P_IDENT(per);
107
108 pmux = gpio_array[gpio_bank(ident)]->port_mux;
109
110 return pmux >> (2 * gpio_sub_n(ident)) & 0x3;
111 }
112
get_gpio_dir(unsigned gpio)113 unsigned short get_gpio_dir(unsigned gpio)
114 {
115 return 0x01 &
116 (gpio_array[gpio_bank(gpio)]->dir_clear >> gpio_sub_n(gpio));
117 }
118
119 /***********************************************************
120 *
121 * FUNCTIONS: Peripheral Resource Allocation
122 * and PortMux Setup
123 *
124 * INPUTS/OUTPUTS:
125 * per Peripheral Identifier
126 * label String
127 *
128 * DESCRIPTION: Peripheral Resource Allocation and Setup API
129 **************************************************************/
130
peripheral_request(unsigned short per,const char * label)131 int peripheral_request(unsigned short per, const char *label)
132 {
133 unsigned short ident = P_IDENT(per);
134
135 /*
136 * Don't cares are pins with only one dedicated function
137 */
138
139 if (per & P_DONTCARE)
140 return 0;
141
142 if (!(per & P_DEFINED))
143 return -EINVAL;
144
145 BUG_ON(ident >= MAX_RESOURCES);
146
147 /* If a pin can be muxed as either GPIO or peripheral, make
148 * sure it is not already a GPIO pin when we request it.
149 */
150 if (unlikely(!check_gpio(ident) && is_reserved(gpio, ident, 1))) {
151 printf("%s: Peripheral %d is already reserved as GPIO by %s!\n",
152 __func__, ident, get_label(ident));
153 return -EBUSY;
154 }
155
156 if (unlikely(is_reserved(peri, ident, 1))) {
157 /*
158 * Pin functions like AMC address strobes my
159 * be requested and used by several drivers
160 */
161
162 if (!((per & P_MAYSHARE) &&
163 get_portmux(per) == P_FUNCT2MUX(per))) {
164 /*
165 * Allow that the identical pin function can
166 * be requested from the same driver twice
167 */
168
169 if (cmp_label(ident, label) == 0)
170 goto anyway;
171
172 printf("%s: Peripheral %d function %d is already "
173 "reserved by %s!\n", __func__, ident,
174 P_FUNCT2MUX(per), get_label(ident));
175 return -EBUSY;
176 }
177 }
178
179 anyway:
180 reserve(peri, ident);
181
182 portmux_setup(per);
183 port_setup(ident, PERIPHERAL_USAGE);
184
185 set_label(ident, label);
186
187 return 0;
188 }
189
peripheral_request_list(const unsigned short per[],const char * label)190 int peripheral_request_list(const unsigned short per[], const char *label)
191 {
192 u16 cnt;
193 int ret;
194
195 for (cnt = 0; per[cnt] != 0; cnt++) {
196 ret = peripheral_request(per[cnt], label);
197
198 if (ret < 0) {
199 for (; cnt > 0; cnt--)
200 peripheral_free(per[cnt - 1]);
201
202 return ret;
203 }
204 }
205
206 return 0;
207 }
208
peripheral_free(unsigned short per)209 void peripheral_free(unsigned short per)
210 {
211 unsigned short ident = P_IDENT(per);
212
213 if (per & P_DONTCARE)
214 return;
215
216 if (!(per & P_DEFINED))
217 return;
218
219 if (unlikely(!is_reserved(peri, ident, 0)))
220 return;
221
222 if (!(per & P_MAYSHARE))
223 port_setup(ident, GPIO_USAGE);
224
225 unreserve(peri, ident);
226
227 set_label(ident, "free");
228 }
229
peripheral_free_list(const unsigned short per[])230 void peripheral_free_list(const unsigned short per[])
231 {
232 u16 cnt;
233 for (cnt = 0; per[cnt] != 0; cnt++)
234 peripheral_free(per[cnt]);
235 }
236
237 /***********************************************************
238 *
239 * FUNCTIONS: GPIO Driver
240 *
241 * INPUTS/OUTPUTS:
242 * gpio PIO Number between 0 and MAX_GPIOS
243 * label String
244 *
245 * DESCRIPTION: GPIO Driver API
246 **************************************************************/
247
gpio_request(unsigned gpio,const char * label)248 int gpio_request(unsigned gpio, const char *label)
249 {
250 if (check_gpio(gpio) < 0)
251 return -EINVAL;
252
253 /*
254 * Allow that the identical GPIO can
255 * be requested from the same driver twice
256 * Do nothing and return -
257 */
258
259 if (cmp_label(gpio, label) == 0)
260 return 0;
261
262 if (unlikely(is_reserved(gpio, gpio, 1))) {
263 printf("adi_gpio2: GPIO %d is already reserved by %s!\n",
264 gpio, get_label(gpio));
265 return -EBUSY;
266 }
267 if (unlikely(is_reserved(peri, gpio, 1))) {
268 printf("adi_gpio2: GPIO %d is already reserved as Peripheral "
269 "by %s!\n", gpio, get_label(gpio));
270 return -EBUSY;
271 }
272
273 reserve(gpio, gpio);
274 set_label(gpio, label);
275
276 port_setup(gpio, GPIO_USAGE);
277
278 return 0;
279 }
280
gpio_free(unsigned gpio)281 int gpio_free(unsigned gpio)
282 {
283 if (check_gpio(gpio) < 0)
284 return -1;
285
286 if (unlikely(!is_reserved(gpio, gpio, 0))) {
287 gpio_error(gpio);
288 return -1;
289 }
290
291 unreserve(gpio, gpio);
292
293 set_label(gpio, "free");
294
295 return 0;
296 }
297
298 #ifdef ADI_SPECIAL_GPIO_BANKS
299 static DECLARE_RESERVED_MAP(special_gpio, gpio_bank(MAX_RESOURCES));
300
special_gpio_request(unsigned gpio,const char * label)301 int special_gpio_request(unsigned gpio, const char *label)
302 {
303 /*
304 * Allow that the identical GPIO can
305 * be requested from the same driver twice
306 * Do nothing and return -
307 */
308
309 if (cmp_label(gpio, label) == 0)
310 return 0;
311
312 if (unlikely(is_reserved(special_gpio, gpio, 1))) {
313 printf("adi_gpio2: GPIO %d is already reserved by %s!\n",
314 gpio, get_label(gpio));
315 return -EBUSY;
316 }
317 if (unlikely(is_reserved(peri, gpio, 1))) {
318 printf("adi_gpio2: GPIO %d is already reserved as Peripheral "
319 "by %s!\n", gpio, get_label(gpio));
320
321 return -EBUSY;
322 }
323
324 reserve(special_gpio, gpio);
325 reserve(peri, gpio);
326
327 set_label(gpio, label);
328 port_setup(gpio, GPIO_USAGE);
329
330 return 0;
331 }
332
special_gpio_free(unsigned gpio)333 void special_gpio_free(unsigned gpio)
334 {
335 if (unlikely(!is_reserved(special_gpio, gpio, 0))) {
336 gpio_error(gpio);
337 return;
338 }
339
340 unreserve(special_gpio, gpio);
341 unreserve(peri, gpio);
342 set_label(gpio, "free");
343 }
344 #endif
345
__gpio_direction_input(unsigned gpio)346 static inline void __gpio_direction_input(unsigned gpio)
347 {
348 gpio_array[gpio_bank(gpio)]->dir_clear = gpio_bit(gpio);
349 #if defined(CONFIG_BF54x)
350 gpio_array[gpio_bank(gpio)]->inen |= gpio_bit(gpio);
351 #else
352 gpio_array[gpio_bank(gpio)]->inen_set = gpio_bit(gpio);
353 #endif
354 }
355
gpio_direction_input(unsigned gpio)356 int gpio_direction_input(unsigned gpio)
357 {
358 unsigned long flags;
359
360 if (!is_reserved(gpio, gpio, 0)) {
361 gpio_error(gpio);
362 return -EINVAL;
363 }
364
365 local_irq_save(flags);
366 __gpio_direction_input(gpio);
367 local_irq_restore(flags);
368
369 return 0;
370 }
371
gpio_set_value(unsigned gpio,int arg)372 int gpio_set_value(unsigned gpio, int arg)
373 {
374 if (arg)
375 gpio_array[gpio_bank(gpio)]->data_set = gpio_bit(gpio);
376 else
377 gpio_array[gpio_bank(gpio)]->data_clear = gpio_bit(gpio);
378
379 return 0;
380 }
381
gpio_direction_output(unsigned gpio,int value)382 int gpio_direction_output(unsigned gpio, int value)
383 {
384 unsigned long flags;
385
386 if (!is_reserved(gpio, gpio, 0)) {
387 gpio_error(gpio);
388 return -EINVAL;
389 }
390
391 local_irq_save(flags);
392
393 #if defined(CONFIG_BF54x)
394 gpio_array[gpio_bank(gpio)]->inen &= ~gpio_bit(gpio);
395 #else
396 gpio_array[gpio_bank(gpio)]->inen_clear = gpio_bit(gpio);
397 #endif
398 gpio_set_value(gpio, value);
399 gpio_array[gpio_bank(gpio)]->dir_set = gpio_bit(gpio);
400
401 local_irq_restore(flags);
402
403 return 0;
404 }
405
gpio_get_value(unsigned gpio)406 int gpio_get_value(unsigned gpio)
407 {
408 return 1 & (gpio_array[gpio_bank(gpio)]->data >> gpio_sub_n(gpio));
409 }
410
gpio_labels(void)411 void gpio_labels(void)
412 {
413 int c, gpio;
414
415 for (c = 0; c < MAX_RESOURCES; c++) {
416 gpio = is_reserved(gpio, c, 1);
417 if (!check_gpio(c) && gpio)
418 printf("GPIO_%d:\t%s\tGPIO %s\n", c, get_label(c),
419 get_gpio_dir(c) ? "OUTPUT" : "INPUT");
420 else if (is_reserved(peri, c, 1))
421 printf("GPIO_%d:\t%s\tPeripheral\n", c, get_label(c));
422 else
423 continue;
424 }
425 }
426