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authorMagnus Damm <damm@igel.co.jp>2008-10-08 07:41:43 -0400
committerPaul Mundt <lethal@linux-sh.org>2008-10-19 21:33:50 -0400
commit2967dab1ae37e30f1b71316513b49fd25c42eabe (patch)
treebe64bed50df72f3444e6b2f5fd8c8bbbeb788a22 /arch/sh/kernel/gpio.c
parent14866543ad22014a0b12e10657a917eb6b487248 (diff)
sh: GPIO and pinmux base code
This patch adds gpio code together with the pinmux table parser. In the future we should optimize this and switch back to gpiolib. Signed-off-by: Magnus Damm <damm@igel.co.jp> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Diffstat (limited to 'arch/sh/kernel/gpio.c')
-rw-r--r--arch/sh/kernel/gpio.c498
1 files changed, 498 insertions, 0 deletions
diff --git a/arch/sh/kernel/gpio.c b/arch/sh/kernel/gpio.c
new file mode 100644
index 000000000000..bb8b812c6895
--- /dev/null
+++ b/arch/sh/kernel/gpio.c
@@ -0,0 +1,498 @@
1/*
2 * Pinmuxed GPIO support for SuperH.
3 *
4 * Copyright (C) 2008 Magnus Damm
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file "COPYING" in the main directory of this archive
8 * for more details.
9 */
10
11#include <linux/errno.h>
12#include <linux/kernel.h>
13#include <linux/list.h>
14#include <linux/module.h>
15#include <linux/clk.h>
16#include <linux/err.h>
17#include <linux/io.h>
18#include <linux/irq.h>
19#include <linux/bitops.h>
20#include <linux/gpio.h>
21
22static struct pinmux_info *registered_gpio;
23
24static struct pinmux_info *gpio_controller(unsigned gpio)
25{
26 if (!registered_gpio)
27 return NULL;
28
29 if (gpio < registered_gpio->first_gpio)
30 return NULL;
31
32 if (gpio > registered_gpio->last_gpio)
33 return NULL;
34
35 return registered_gpio;
36}
37
38static int enum_in_range(pinmux_enum_t enum_id, struct pinmux_range *r)
39{
40 if (enum_id < r->begin)
41 return 0;
42
43 if (enum_id > r->end)
44 return 0;
45
46 return 1;
47}
48
49static int read_write_reg(unsigned long reg, unsigned long reg_width,
50 unsigned long field_width, unsigned long in_pos,
51 unsigned long value, int do_write)
52{
53 unsigned long data, mask, pos;
54
55 data = 0;
56 mask = (1 << field_width) - 1;
57 pos = reg_width - ((in_pos + 1) * field_width);
58
59#ifdef DEBUG
60 pr_info("%s, addr = %lx, value = %ld, pos = %ld, "
61 "r_width = %ld, f_width = %ld\n",
62 do_write ? "write" : "read", reg, value, pos,
63 reg_width, field_width);
64#endif
65
66 switch (reg_width) {
67 case 8:
68 data = ctrl_inb(reg);
69 break;
70 case 16:
71 data = ctrl_inw(reg);
72 break;
73 case 32:
74 data = ctrl_inl(reg);
75 break;
76 }
77
78 if (!do_write)
79 return (data >> pos) & mask;
80
81 data &= ~(mask << pos);
82 data |= value << pos;
83
84 switch (reg_width) {
85 case 8:
86 ctrl_outb(data, reg);
87 break;
88 case 16:
89 ctrl_outw(data, reg);
90 break;
91 case 32:
92 ctrl_outl(data, reg);
93 break;
94 }
95 return 0;
96}
97
98static int get_data_reg(struct pinmux_info *gpioc, unsigned gpio,
99 struct pinmux_data_reg **drp, int *bitp)
100{
101 pinmux_enum_t enum_id = gpioc->gpios[gpio].enum_id;
102 struct pinmux_data_reg *data_reg;
103 int k, n;
104
105 if (!enum_in_range(enum_id, &gpioc->data))
106 return -1;
107
108 k = 0;
109 while (1) {
110 data_reg = gpioc->data_regs + k;
111
112 if (!data_reg->reg_width)
113 break;
114
115 for (n = 0; n < data_reg->reg_width; n++) {
116 if (data_reg->enum_ids[n] == enum_id) {
117 *drp = data_reg;
118 *bitp = n;
119 return 0;
120
121 }
122 }
123 k++;
124 }
125
126 return -1;
127}
128
129static int get_config_reg(struct pinmux_info *gpioc, pinmux_enum_t enum_id,
130 struct pinmux_cfg_reg **crp, int *indexp,
131 unsigned long **cntp)
132{
133 struct pinmux_cfg_reg *config_reg;
134 unsigned long r_width, f_width;
135 int k, n;
136
137 k = 0;
138 while (1) {
139 config_reg = gpioc->cfg_regs + k;
140
141 r_width = config_reg->reg_width;
142 f_width = config_reg->field_width;
143
144 if (!r_width)
145 break;
146 for (n = 0; n < (r_width / f_width) * 1 << f_width; n++) {
147 if (config_reg->enum_ids[n] == enum_id) {
148 *crp = config_reg;
149 *indexp = n;
150 *cntp = &config_reg->cnt[n / (1 << f_width)];
151 return 0;
152 }
153 }
154 k++;
155 }
156
157 return -1;
158}
159
160static int get_gpio_enum_id(struct pinmux_info *gpioc, unsigned gpio,
161 int pos, pinmux_enum_t *enum_idp)
162{
163 pinmux_enum_t enum_id = gpioc->gpios[gpio].enum_id;
164 pinmux_enum_t *data = gpioc->gpio_data;
165 int k;
166
167 if (!enum_in_range(enum_id, &gpioc->data)) {
168 if (!enum_in_range(enum_id, &gpioc->mark)) {
169 pr_err("non data/mark enum_id for gpio %d\n", gpio);
170 return -1;
171 }
172 }
173
174 if (pos) {
175 *enum_idp = data[pos + 1];
176 return pos + 1;
177 }
178
179 for (k = 0; k < gpioc->gpio_data_size; k++) {
180 if (data[k] == enum_id) {
181 *enum_idp = data[k + 1];
182 return k + 1;
183 }
184 }
185
186 pr_err("cannot locate data/mark enum_id for gpio %d\n", gpio);
187 return -1;
188}
189
190static int write_config_reg(struct pinmux_info *gpioc,
191 struct pinmux_cfg_reg *crp,
192 int index)
193{
194 unsigned long ncomb, pos, value;
195
196 ncomb = 1 << crp->field_width;
197 pos = index / ncomb;
198 value = index % ncomb;
199
200 return read_write_reg(crp->reg, crp->reg_width,
201 crp->field_width, pos, value, 1);
202}
203
204static int check_config_reg(struct pinmux_info *gpioc,
205 struct pinmux_cfg_reg *crp,
206 int index)
207{
208 unsigned long ncomb, pos, value;
209
210 ncomb = 1 << crp->field_width;
211 pos = index / ncomb;
212 value = index % ncomb;
213
214 if (read_write_reg(crp->reg, crp->reg_width,
215 crp->field_width, pos, 0, 0) == value)
216 return 0;
217
218 return -1;
219}
220
221enum { GPIO_CFG_DRYRUN, GPIO_CFG_REQ, GPIO_CFG_FREE };
222
223int pinmux_config_gpio(struct pinmux_info *gpioc, unsigned gpio,
224 int pinmux_type, int cfg_mode)
225{
226 struct pinmux_cfg_reg *cr = NULL;
227 pinmux_enum_t enum_id;
228 struct pinmux_range *range;
229 int in_range, pos, index;
230 unsigned long *cntp;
231
232 switch (pinmux_type) {
233
234 case PINMUX_TYPE_FUNCTION:
235 range = NULL;
236 break;
237
238 case PINMUX_TYPE_OUTPUT:
239 range = &gpioc->output;
240 break;
241
242 case PINMUX_TYPE_INPUT:
243 range = &gpioc->input;
244 break;
245
246 case PINMUX_TYPE_INPUT_PULLUP:
247 range = &gpioc->input_pu;
248 break;
249
250 case PINMUX_TYPE_INPUT_PULLDOWN:
251 range = &gpioc->input_pd;
252 break;
253
254 default:
255 goto out_err;
256 }
257
258 pos = 0;
259 enum_id = 0;
260 index = 0;
261 while (1) {
262 pos = get_gpio_enum_id(gpioc, gpio, pos, &enum_id);
263 if (pos <= 0)
264 goto out_err;
265
266 if (!enum_id)
267 break;
268
269 in_range = enum_in_range(enum_id, &gpioc->function);
270 if (!in_range && range)
271 in_range = enum_in_range(enum_id, range);
272
273 if (!in_range)
274 continue;
275
276 if (get_config_reg(gpioc, enum_id, &cr, &index, &cntp) != 0)
277 goto out_err;
278
279 switch (cfg_mode) {
280 case GPIO_CFG_DRYRUN:
281 if (!*cntp || !check_config_reg(gpioc, cr, index))
282 continue;
283 break;
284
285 case GPIO_CFG_REQ:
286 if (write_config_reg(gpioc, cr, index) != 0)
287 goto out_err;
288 *cntp = *cntp + 1;
289 break;
290
291 case GPIO_CFG_FREE:
292 *cntp = *cntp - 1;
293 break;
294 }
295 }
296
297 return 0;
298 out_err:
299 return -1;
300}
301
302static DEFINE_SPINLOCK(gpio_lock);
303
304int __gpio_request(unsigned gpio)
305{
306 struct pinmux_info *gpioc = gpio_controller(gpio);
307 struct pinmux_data_reg *dummy;
308 unsigned long flags;
309 int i, ret, pinmux_type;
310
311 ret = -EINVAL;
312
313 if (!gpioc)
314 goto err_out;
315
316 spin_lock_irqsave(&gpio_lock, flags);
317
318 if ((gpioc->gpios[gpio].flags & PINMUX_FLAG_TYPE) != PINMUX_TYPE_NONE)
319 goto err_unlock;
320
321 /* setup pin function here if no data is associated with pin */
322
323 if (get_data_reg(gpioc, gpio, &dummy, &i) != 0)
324 pinmux_type = PINMUX_TYPE_FUNCTION;
325 else
326 pinmux_type = PINMUX_TYPE_GPIO;
327
328 if (pinmux_type == PINMUX_TYPE_FUNCTION) {
329 if (pinmux_config_gpio(gpioc, gpio,
330 pinmux_type,
331 GPIO_CFG_DRYRUN) != 0)
332 goto err_unlock;
333
334 if (pinmux_config_gpio(gpioc, gpio,
335 pinmux_type,
336 GPIO_CFG_REQ) != 0)
337 BUG();
338 }
339
340 gpioc->gpios[gpio].flags = pinmux_type;
341
342 ret = 0;
343 err_unlock:
344 spin_unlock_irqrestore(&gpio_lock, flags);
345 err_out:
346 return ret;
347}
348EXPORT_SYMBOL(__gpio_request);
349
350void gpio_free(unsigned gpio)
351{
352 struct pinmux_info *gpioc = gpio_controller(gpio);
353 unsigned long flags;
354 int pinmux_type;
355
356 if (!gpioc)
357 return;
358
359 spin_lock_irqsave(&gpio_lock, flags);
360
361 pinmux_type = gpioc->gpios[gpio].flags & PINMUX_FLAG_TYPE;
362 pinmux_config_gpio(gpioc, gpio, pinmux_type, GPIO_CFG_FREE);
363 gpioc->gpios[gpio].flags = PINMUX_TYPE_NONE;
364
365 spin_unlock_irqrestore(&gpio_lock, flags);
366}
367EXPORT_SYMBOL(gpio_free);
368
369static int pinmux_direction(struct pinmux_info *gpioc,
370 unsigned gpio, int new_pinmux_type)
371{
372 int ret, pinmux_type;
373
374 ret = -EINVAL;
375 pinmux_type = gpioc->gpios[gpio].flags & PINMUX_FLAG_TYPE;
376
377 switch (pinmux_type) {
378 case PINMUX_TYPE_GPIO:
379 break;
380 case PINMUX_TYPE_OUTPUT:
381 case PINMUX_TYPE_INPUT:
382 case PINMUX_TYPE_INPUT_PULLUP:
383 case PINMUX_TYPE_INPUT_PULLDOWN:
384 pinmux_config_gpio(gpioc, gpio, pinmux_type, GPIO_CFG_FREE);
385 break;
386 default:
387 goto err_out;
388 }
389
390 if (pinmux_config_gpio(gpioc, gpio,
391 new_pinmux_type,
392 GPIO_CFG_DRYRUN) != 0)
393 goto err_out;
394
395 if (pinmux_config_gpio(gpioc, gpio,
396 new_pinmux_type,
397 GPIO_CFG_REQ) != 0)
398 BUG();
399
400 gpioc->gpios[gpio].flags = new_pinmux_type;
401
402 ret = 0;
403 err_out:
404 return ret;
405}
406
407int gpio_direction_input(unsigned gpio)
408{
409 struct pinmux_info *gpioc = gpio_controller(gpio);
410 unsigned long flags;
411 int ret = -EINVAL;
412
413 if (!gpioc)
414 goto err_out;
415
416 spin_lock_irqsave(&gpio_lock, flags);
417 ret = pinmux_direction(gpioc, gpio, PINMUX_TYPE_INPUT);
418 spin_unlock_irqrestore(&gpio_lock, flags);
419 err_out:
420 return ret;
421}
422EXPORT_SYMBOL(gpio_direction_input);
423
424static int __gpio_get_set_value(struct pinmux_info *gpioc,
425 unsigned gpio, int value,
426 int do_write)
427{
428 struct pinmux_data_reg *dr = NULL;
429 int bit = 0;
430
431 if (get_data_reg(gpioc, gpio, &dr, &bit) != 0)
432 BUG();
433 else
434 value = read_write_reg(dr->reg, dr->reg_width,
435 1, bit, value, do_write);
436
437 return value;
438}
439
440int gpio_direction_output(unsigned gpio, int value)
441{
442 struct pinmux_info *gpioc = gpio_controller(gpio);
443 unsigned long flags;
444 int ret = -EINVAL;
445
446 if (!gpioc)
447 goto err_out;
448
449 spin_lock_irqsave(&gpio_lock, flags);
450 __gpio_get_set_value(gpioc, gpio, value, 1);
451 ret = pinmux_direction(gpioc, gpio, PINMUX_TYPE_OUTPUT);
452 spin_unlock_irqrestore(&gpio_lock, flags);
453 err_out:
454 return ret;
455}
456EXPORT_SYMBOL(gpio_direction_output);
457
458int gpio_get_value(unsigned gpio)
459{
460 struct pinmux_info *gpioc = gpio_controller(gpio);
461 unsigned long flags;
462 int value = 0;
463
464 if (!gpioc)
465 BUG();
466 else {
467 spin_lock_irqsave(&gpio_lock, flags);
468 value = __gpio_get_set_value(gpioc, gpio, 0, 0);
469 spin_unlock_irqrestore(&gpio_lock, flags);
470 }
471
472 return value;
473}
474EXPORT_SYMBOL(gpio_get_value);
475
476void gpio_set_value(unsigned gpio, int value)
477{
478 struct pinmux_info *gpioc = gpio_controller(gpio);
479 unsigned long flags;
480
481 if (!gpioc)
482 BUG();
483 else {
484 spin_lock_irqsave(&gpio_lock, flags);
485 __gpio_get_set_value(gpioc, gpio, value, 1);
486 spin_unlock_irqrestore(&gpio_lock, flags);
487 }
488}
489EXPORT_SYMBOL(gpio_set_value);
490
491int register_pinmux(struct pinmux_info *pip)
492{
493 registered_gpio = pip;
494 pr_info("pinmux: %s handling gpio %d -> %d\n",
495 pip->name, pip->first_gpio, pip->last_gpio);
496
497 return 0;
498}