amba: Add Kconfig file
[linux-block.git] / drivers / gpio / gpio-stmpe.c
CommitLineData
03f822f5
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1/*
2 * Copyright (C) ST-Ericsson SA 2010
3 *
4 * License Terms: GNU General Public License, version 2
5 * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
6 */
7
8#include <linux/module.h>
9#include <linux/init.h>
10#include <linux/platform_device.h>
11#include <linux/slab.h>
12#include <linux/gpio.h>
03f822f5 13#include <linux/interrupt.h>
86605cfe 14#include <linux/of.h>
03f822f5 15#include <linux/mfd/stmpe.h>
27ec8a9c 16#include <linux/seq_file.h>
03f822f5
RV
17
18/*
19 * These registers are modified under the irq bus lock and cached to avoid
20 * unnecessary writes in bus_sync_unlock.
21 */
22enum { REG_RE, REG_FE, REG_IE };
23
24#define CACHE_NR_REGS 3
9e9dc7d9
LW
25/* No variant has more than 24 GPIOs */
26#define CACHE_NR_BANKS (24 / 8)
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27
28struct stmpe_gpio {
29 struct gpio_chip chip;
30 struct stmpe *stmpe;
31 struct device *dev;
32 struct mutex irq_lock;
b8e9cf0b 33 unsigned norequest_mask;
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34 /* Caches of interrupt control registers for bus_lock */
35 u8 regs[CACHE_NR_REGS][CACHE_NR_BANKS];
36 u8 oldregs[CACHE_NR_REGS][CACHE_NR_BANKS];
37};
38
39static inline struct stmpe_gpio *to_stmpe_gpio(struct gpio_chip *chip)
40{
41 return container_of(chip, struct stmpe_gpio, chip);
42}
43
44static int stmpe_gpio_get(struct gpio_chip *chip, unsigned offset)
45{
46 struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(chip);
47 struct stmpe *stmpe = stmpe_gpio->stmpe;
48 u8 reg = stmpe->regs[STMPE_IDX_GPMR_LSB] - (offset / 8);
49 u8 mask = 1 << (offset % 8);
50 int ret;
51
52 ret = stmpe_reg_read(stmpe, reg);
53 if (ret < 0)
54 return ret;
55
7535b8be 56 return !!(ret & mask);
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57}
58
59static void stmpe_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
60{
61 struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(chip);
62 struct stmpe *stmpe = stmpe_gpio->stmpe;
63 int which = val ? STMPE_IDX_GPSR_LSB : STMPE_IDX_GPCR_LSB;
64 u8 reg = stmpe->regs[which] - (offset / 8);
65 u8 mask = 1 << (offset % 8);
66
cccdceb9
VK
67 /*
68 * Some variants have single register for gpio set/clear functionality.
69 * For them we need to write 0 to clear and 1 to set.
70 */
71 if (stmpe->regs[STMPE_IDX_GPSR_LSB] == stmpe->regs[STMPE_IDX_GPCR_LSB])
72 stmpe_set_bits(stmpe, reg, mask, val ? mask : 0);
73 else
74 stmpe_reg_write(stmpe, reg, mask);
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75}
76
77static int stmpe_gpio_direction_output(struct gpio_chip *chip,
78 unsigned offset, int val)
79{
80 struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(chip);
81 struct stmpe *stmpe = stmpe_gpio->stmpe;
82 u8 reg = stmpe->regs[STMPE_IDX_GPDR_LSB] - (offset / 8);
83 u8 mask = 1 << (offset % 8);
84
85 stmpe_gpio_set(chip, offset, val);
86
87 return stmpe_set_bits(stmpe, reg, mask, mask);
88}
89
90static int stmpe_gpio_direction_input(struct gpio_chip *chip,
91 unsigned offset)
92{
93 struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(chip);
94 struct stmpe *stmpe = stmpe_gpio->stmpe;
95 u8 reg = stmpe->regs[STMPE_IDX_GPDR_LSB] - (offset / 8);
96 u8 mask = 1 << (offset % 8);
97
98 return stmpe_set_bits(stmpe, reg, mask, 0);
99}
100
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101static int stmpe_gpio_request(struct gpio_chip *chip, unsigned offset)
102{
103 struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(chip);
104 struct stmpe *stmpe = stmpe_gpio->stmpe;
105
b8e9cf0b
WS
106 if (stmpe_gpio->norequest_mask & (1 << offset))
107 return -EINVAL;
108
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109 return stmpe_set_altfunc(stmpe, 1 << offset, STMPE_BLOCK_GPIO);
110}
111
112static struct gpio_chip template_chip = {
113 .label = "stmpe",
114 .owner = THIS_MODULE,
115 .direction_input = stmpe_gpio_direction_input,
116 .get = stmpe_gpio_get,
117 .direction_output = stmpe_gpio_direction_output,
118 .set = stmpe_gpio_set,
03f822f5 119 .request = stmpe_gpio_request,
9fb1f39e 120 .can_sleep = true,
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121};
122
2a866f39 123static int stmpe_gpio_irq_set_type(struct irq_data *d, unsigned int type)
03f822f5 124{
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125 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
126 struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(gc);
fc13d5a5 127 int offset = d->hwirq;
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128 int regoffset = offset / 8;
129 int mask = 1 << (offset % 8);
130
1fe3bd9e 131 if (type & IRQ_TYPE_LEVEL_LOW || type & IRQ_TYPE_LEVEL_HIGH)
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132 return -EINVAL;
133
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134 /* STMPE801 doesn't have RE and FE registers */
135 if (stmpe_gpio->stmpe->partnum == STMPE801)
136 return 0;
137
1fe3bd9e 138 if (type & IRQ_TYPE_EDGE_RISING)
03f822f5
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139 stmpe_gpio->regs[REG_RE][regoffset] |= mask;
140 else
141 stmpe_gpio->regs[REG_RE][regoffset] &= ~mask;
142
1fe3bd9e 143 if (type & IRQ_TYPE_EDGE_FALLING)
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144 stmpe_gpio->regs[REG_FE][regoffset] |= mask;
145 else
146 stmpe_gpio->regs[REG_FE][regoffset] &= ~mask;
147
148 return 0;
149}
150
2a866f39 151static void stmpe_gpio_irq_lock(struct irq_data *d)
03f822f5 152{
fe44e70d
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153 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
154 struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(gc);
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155
156 mutex_lock(&stmpe_gpio->irq_lock);
157}
158
2a866f39 159static void stmpe_gpio_irq_sync_unlock(struct irq_data *d)
03f822f5 160{
fe44e70d
LW
161 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
162 struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(gc);
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163 struct stmpe *stmpe = stmpe_gpio->stmpe;
164 int num_banks = DIV_ROUND_UP(stmpe->num_gpios, 8);
165 static const u8 regmap[] = {
166 [REG_RE] = STMPE_IDX_GPRER_LSB,
167 [REG_FE] = STMPE_IDX_GPFER_LSB,
168 [REG_IE] = STMPE_IDX_IEGPIOR_LSB,
169 };
170 int i, j;
171
172 for (i = 0; i < CACHE_NR_REGS; i++) {
cccdceb9
VK
173 /* STMPE801 doesn't have RE and FE registers */
174 if ((stmpe->partnum == STMPE801) &&
175 (i != REG_IE))
176 continue;
177
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178 for (j = 0; j < num_banks; j++) {
179 u8 old = stmpe_gpio->oldregs[i][j];
180 u8 new = stmpe_gpio->regs[i][j];
181
182 if (new == old)
183 continue;
184
185 stmpe_gpio->oldregs[i][j] = new;
186 stmpe_reg_write(stmpe, stmpe->regs[regmap[i]] - j, new);
187 }
188 }
189
190 mutex_unlock(&stmpe_gpio->irq_lock);
191}
192
2a866f39 193static void stmpe_gpio_irq_mask(struct irq_data *d)
03f822f5 194{
fe44e70d
LW
195 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
196 struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(gc);
fc13d5a5 197 int offset = d->hwirq;
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198 int regoffset = offset / 8;
199 int mask = 1 << (offset % 8);
200
201 stmpe_gpio->regs[REG_IE][regoffset] &= ~mask;
202}
203
2a866f39 204static void stmpe_gpio_irq_unmask(struct irq_data *d)
03f822f5 205{
fe44e70d
LW
206 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
207 struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(gc);
fc13d5a5 208 int offset = d->hwirq;
03f822f5
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209 int regoffset = offset / 8;
210 int mask = 1 << (offset % 8);
211
212 stmpe_gpio->regs[REG_IE][regoffset] |= mask;
213}
214
27ec8a9c
LW
215static void stmpe_dbg_show_one(struct seq_file *s,
216 struct gpio_chip *gc,
217 unsigned offset, unsigned gpio)
218{
219 struct stmpe_gpio *stmpe_gpio = to_stmpe_gpio(gc);
220 struct stmpe *stmpe = stmpe_gpio->stmpe;
221 const char *label = gpiochip_is_requested(gc, offset);
222 int num_banks = DIV_ROUND_UP(stmpe->num_gpios, 8);
223 bool val = !!stmpe_gpio_get(gc, offset);
224 u8 dir_reg = stmpe->regs[STMPE_IDX_GPDR_LSB] - (offset / 8);
225 u8 mask = 1 << (offset % 8);
226 int ret;
227 u8 dir;
228
229 ret = stmpe_reg_read(stmpe, dir_reg);
230 if (ret < 0)
231 return;
232 dir = !!(ret & mask);
233
234 if (dir) {
235 seq_printf(s, " gpio-%-3d (%-20.20s) out %s",
236 gpio, label ?: "(none)",
237 val ? "hi" : "lo");
238 } else {
239 u8 edge_det_reg = stmpe->regs[STMPE_IDX_GPEDR_MSB] + num_banks - 1 - (offset / 8);
240 u8 rise_reg = stmpe->regs[STMPE_IDX_GPRER_LSB] - (offset / 8);
241 u8 fall_reg = stmpe->regs[STMPE_IDX_GPFER_LSB] - (offset / 8);
242 u8 irqen_reg = stmpe->regs[STMPE_IDX_IEGPIOR_LSB] - (offset / 8);
243 bool edge_det;
244 bool rise;
245 bool fall;
246 bool irqen;
247
248 ret = stmpe_reg_read(stmpe, edge_det_reg);
249 if (ret < 0)
250 return;
251 edge_det = !!(ret & mask);
252 ret = stmpe_reg_read(stmpe, rise_reg);
253 if (ret < 0)
254 return;
255 rise = !!(ret & mask);
256 ret = stmpe_reg_read(stmpe, fall_reg);
257 if (ret < 0)
258 return;
259 fall = !!(ret & mask);
260 ret = stmpe_reg_read(stmpe, irqen_reg);
261 if (ret < 0)
262 return;
263 irqen = !!(ret & mask);
264
265 seq_printf(s, " gpio-%-3d (%-20.20s) in %s %s %s%s%s",
266 gpio, label ?: "(none)",
267 val ? "hi" : "lo",
268 edge_det ? "edge-asserted" : "edge-inactive",
269 irqen ? "IRQ-enabled" : "",
270 rise ? " rising-edge-detection" : "",
271 fall ? " falling-edge-detection" : "");
272 }
273}
274
275static void stmpe_dbg_show(struct seq_file *s, struct gpio_chip *gc)
276{
277 unsigned i;
278 unsigned gpio = gc->base;
279
280 for (i = 0; i < gc->ngpio; i++, gpio++) {
281 stmpe_dbg_show_one(s, gc, i, gpio);
282 seq_printf(s, "\n");
283 }
284}
285
03f822f5
RV
286static struct irq_chip stmpe_gpio_irq_chip = {
287 .name = "stmpe-gpio",
2a866f39
LB
288 .irq_bus_lock = stmpe_gpio_irq_lock,
289 .irq_bus_sync_unlock = stmpe_gpio_irq_sync_unlock,
290 .irq_mask = stmpe_gpio_irq_mask,
291 .irq_unmask = stmpe_gpio_irq_unmask,
292 .irq_set_type = stmpe_gpio_irq_set_type,
03f822f5
RV
293};
294
295static irqreturn_t stmpe_gpio_irq(int irq, void *dev)
296{
297 struct stmpe_gpio *stmpe_gpio = dev;
298 struct stmpe *stmpe = stmpe_gpio->stmpe;
299 u8 statmsbreg = stmpe->regs[STMPE_IDX_ISGPIOR_MSB];
300 int num_banks = DIV_ROUND_UP(stmpe->num_gpios, 8);
301 u8 status[num_banks];
302 int ret;
303 int i;
304
305 ret = stmpe_block_read(stmpe, statmsbreg, num_banks, status);
306 if (ret < 0)
307 return IRQ_NONE;
308
309 for (i = 0; i < num_banks; i++) {
310 int bank = num_banks - i - 1;
311 unsigned int enabled = stmpe_gpio->regs[REG_IE][bank];
312 unsigned int stat = status[i];
313
314 stat &= enabled;
315 if (!stat)
316 continue;
317
318 while (stat) {
319 int bit = __ffs(stat);
320 int line = bank * 8 + bit;
fe44e70d 321 int child_irq = irq_find_mapping(stmpe_gpio->chip.irqdomain,
ed05e204 322 line);
03f822f5 323
ed05e204 324 handle_nested_irq(child_irq);
03f822f5
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325 stat &= ~(1 << bit);
326 }
327
328 stmpe_reg_write(stmpe, statmsbreg + i, status[i]);
cccdceb9
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329
330 /* Edge detect register is not present on 801 */
331 if (stmpe->partnum != STMPE801)
332 stmpe_reg_write(stmpe, stmpe->regs[STMPE_IDX_GPEDR_MSB]
333 + i, status[i]);
03f822f5
RV
334 }
335
336 return IRQ_HANDLED;
337}
338
3836309d 339static int stmpe_gpio_probe(struct platform_device *pdev)
03f822f5
RV
340{
341 struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent);
86605cfe 342 struct device_node *np = pdev->dev.of_node;
03f822f5
RV
343 struct stmpe_gpio_platform_data *pdata;
344 struct stmpe_gpio *stmpe_gpio;
345 int ret;
38040c85 346 int irq = 0;
03f822f5
RV
347
348 pdata = stmpe->pdata->gpio;
03f822f5
RV
349
350 irq = platform_get_irq(pdev, 0);
03f822f5
RV
351
352 stmpe_gpio = kzalloc(sizeof(struct stmpe_gpio), GFP_KERNEL);
353 if (!stmpe_gpio)
354 return -ENOMEM;
355
356 mutex_init(&stmpe_gpio->irq_lock);
357
358 stmpe_gpio->dev = &pdev->dev;
359 stmpe_gpio->stmpe = stmpe;
03f822f5
RV
360 stmpe_gpio->chip = template_chip;
361 stmpe_gpio->chip.ngpio = stmpe->num_gpios;
362 stmpe_gpio->chip.dev = &pdev->dev;
9afd9b70
GF
363#ifdef CONFIG_OF
364 stmpe_gpio->chip.of_node = np;
365#endif
9e9dc7d9 366 stmpe_gpio->chip.base = -1;
03f822f5 367
27ec8a9c
LW
368 if (IS_ENABLED(CONFIG_DEBUG_FS))
369 stmpe_gpio->chip.dbg_show = stmpe_dbg_show;
370
86605cfe
VKS
371 if (pdata)
372 stmpe_gpio->norequest_mask = pdata->norequest_mask;
373 else if (np)
374 of_property_read_u32(np, "st,norequest-mask",
375 &stmpe_gpio->norequest_mask);
376
9e9dc7d9 377 if (irq < 0)
38040c85 378 dev_info(&pdev->dev,
fe44e70d 379 "device configured in no-irq mode: "
38040c85 380 "irqs are not available\n");
03f822f5
RV
381
382 ret = stmpe_enable(stmpe, STMPE_BLOCK_GPIO);
383 if (ret)
02bf0749 384 goto out_free;
03f822f5 385
3f97d5fc
LW
386 ret = gpiochip_add(&stmpe_gpio->chip);
387 if (ret) {
388 dev_err(&pdev->dev, "unable to add gpiochip: %d\n", ret);
389 goto out_disable;
390 }
391
fe44e70d
LW
392 if (irq > 0) {
393 ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
394 stmpe_gpio_irq, IRQF_ONESHOT,
395 "stmpe-gpio", stmpe_gpio);
38040c85
CB
396 if (ret) {
397 dev_err(&pdev->dev, "unable to get irq: %d\n", ret);
fc13d5a5 398 goto out_disable;
38040c85 399 }
fe44e70d
LW
400 ret = gpiochip_irqchip_add(&stmpe_gpio->chip,
401 &stmpe_gpio_irq_chip,
402 0,
403 handle_simple_irq,
404 IRQ_TYPE_NONE);
405 if (ret) {
406 dev_err(&pdev->dev,
407 "could not connect irqchip to gpiochip\n");
3f97d5fc 408 goto out_disable;
fe44e70d 409 }
03f822f5 410
3f97d5fc
LW
411 gpiochip_set_chained_irqchip(&stmpe_gpio->chip,
412 &stmpe_gpio_irq_chip,
413 irq,
414 NULL);
03f822f5
RV
415 }
416
417 if (pdata && pdata->setup)
418 pdata->setup(stmpe, stmpe_gpio->chip.base);
419
420 platform_set_drvdata(pdev, stmpe_gpio);
421
422 return 0;
423
02bf0749
VK
424out_disable:
425 stmpe_disable(stmpe, STMPE_BLOCK_GPIO);
3f97d5fc 426 gpiochip_remove(&stmpe_gpio->chip);
03f822f5
RV
427out_free:
428 kfree(stmpe_gpio);
429 return ret;
430}
431
206210ce 432static int stmpe_gpio_remove(struct platform_device *pdev)
03f822f5
RV
433{
434 struct stmpe_gpio *stmpe_gpio = platform_get_drvdata(pdev);
435 struct stmpe *stmpe = stmpe_gpio->stmpe;
436 struct stmpe_gpio_platform_data *pdata = stmpe->pdata->gpio;
03f822f5
RV
437
438 if (pdata && pdata->remove)
439 pdata->remove(stmpe, stmpe_gpio->chip.base);
440
9f5132ae 441 gpiochip_remove(&stmpe_gpio->chip);
03f822f5
RV
442
443 stmpe_disable(stmpe, STMPE_BLOCK_GPIO);
444
03f822f5
RV
445 kfree(stmpe_gpio);
446
447 return 0;
448}
449
450static struct platform_driver stmpe_gpio_driver = {
451 .driver.name = "stmpe-gpio",
452 .driver.owner = THIS_MODULE,
453 .probe = stmpe_gpio_probe,
8283c4ff 454 .remove = stmpe_gpio_remove,
03f822f5
RV
455};
456
457static int __init stmpe_gpio_init(void)
458{
459 return platform_driver_register(&stmpe_gpio_driver);
460}
461subsys_initcall(stmpe_gpio_init);
462
463static void __exit stmpe_gpio_exit(void)
464{
465 platform_driver_unregister(&stmpe_gpio_driver);
466}
467module_exit(stmpe_gpio_exit);
468
469MODULE_LICENSE("GPL v2");
470MODULE_DESCRIPTION("STMPExxxx GPIO driver");
471MODULE_AUTHOR("Rabin Vincent <rabin.vincent@stericsson.com>");