1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) ST-Ericsson SA 2010
4  *
5  * Author: Hanumath Prasad <hanumath.prasad@stericsson.com> for ST-Ericsson
6  * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
7  */
8 
9 #include <linux/module.h>
10 #include <linux/interrupt.h>
11 #include <linux/irq.h>
12 #include <linux/irqdomain.h>
13 #include <linux/slab.h>
14 #include <linux/i2c.h>
15 #include <linux/of.h>
16 #include <linux/of_device.h>
17 #include <linux/mfd/core.h>
18 #include <linux/mfd/tc3589x.h>
19 #include <linux/err.h>
20 
21 /*
22  * enum tc3589x_version - indicates the TC3589x version
23  */
24 enum tc3589x_version {
25 	TC3589X_TC35890,
26 	TC3589X_TC35892,
27 	TC3589X_TC35893,
28 	TC3589X_TC35894,
29 	TC3589X_TC35895,
30 	TC3589X_TC35896,
31 	TC3589X_UNKNOWN,
32 };
33 
34 #define TC3589x_CLKMODE_MODCTL_SLEEP		0x0
35 #define TC3589x_CLKMODE_MODCTL_OPERATION	(1 << 0)
36 
37 /**
38  * tc3589x_reg_read() - read a single TC3589x register
39  * @tc3589x:	Device to read from
40  * @reg:	Register to read
41  */
tc3589x_reg_read(struct tc3589x * tc3589x,u8 reg)42 int tc3589x_reg_read(struct tc3589x *tc3589x, u8 reg)
43 {
44 	int ret;
45 
46 	ret = i2c_smbus_read_byte_data(tc3589x->i2c, reg);
47 	if (ret < 0)
48 		dev_err(tc3589x->dev, "failed to read reg %#x: %d\n",
49 			reg, ret);
50 
51 	return ret;
52 }
53 EXPORT_SYMBOL_GPL(tc3589x_reg_read);
54 
55 /**
56  * tc3589x_reg_write() - write a single TC3589x register
57  * @tc3589x:	Device to write to
58  * @reg:	Register to read
59  * @data:	Value to write
60  */
tc3589x_reg_write(struct tc3589x * tc3589x,u8 reg,u8 data)61 int tc3589x_reg_write(struct tc3589x *tc3589x, u8 reg, u8 data)
62 {
63 	int ret;
64 
65 	ret = i2c_smbus_write_byte_data(tc3589x->i2c, reg, data);
66 	if (ret < 0)
67 		dev_err(tc3589x->dev, "failed to write reg %#x: %d\n",
68 			reg, ret);
69 
70 	return ret;
71 }
72 EXPORT_SYMBOL_GPL(tc3589x_reg_write);
73 
74 /**
75  * tc3589x_block_read() - read multiple TC3589x registers
76  * @tc3589x:	Device to read from
77  * @reg:	First register
78  * @length:	Number of registers
79  * @values:	Buffer to write to
80  */
tc3589x_block_read(struct tc3589x * tc3589x,u8 reg,u8 length,u8 * values)81 int tc3589x_block_read(struct tc3589x *tc3589x, u8 reg, u8 length, u8 *values)
82 {
83 	int ret;
84 
85 	ret = i2c_smbus_read_i2c_block_data(tc3589x->i2c, reg, length, values);
86 	if (ret < 0)
87 		dev_err(tc3589x->dev, "failed to read regs %#x: %d\n",
88 			reg, ret);
89 
90 	return ret;
91 }
92 EXPORT_SYMBOL_GPL(tc3589x_block_read);
93 
94 /**
95  * tc3589x_block_write() - write multiple TC3589x registers
96  * @tc3589x:	Device to write to
97  * @reg:	First register
98  * @length:	Number of registers
99  * @values:	Values to write
100  */
tc3589x_block_write(struct tc3589x * tc3589x,u8 reg,u8 length,const u8 * values)101 int tc3589x_block_write(struct tc3589x *tc3589x, u8 reg, u8 length,
102 			const u8 *values)
103 {
104 	int ret;
105 
106 	ret = i2c_smbus_write_i2c_block_data(tc3589x->i2c, reg, length,
107 					     values);
108 	if (ret < 0)
109 		dev_err(tc3589x->dev, "failed to write regs %#x: %d\n",
110 			reg, ret);
111 
112 	return ret;
113 }
114 EXPORT_SYMBOL_GPL(tc3589x_block_write);
115 
116 /**
117  * tc3589x_set_bits() - set the value of a bitfield in a TC3589x register
118  * @tc3589x:	Device to write to
119  * @reg:	Register to write
120  * @mask:	Mask of bits to set
121  * @val:	Value to set
122  */
tc3589x_set_bits(struct tc3589x * tc3589x,u8 reg,u8 mask,u8 val)123 int tc3589x_set_bits(struct tc3589x *tc3589x, u8 reg, u8 mask, u8 val)
124 {
125 	int ret;
126 
127 	mutex_lock(&tc3589x->lock);
128 
129 	ret = tc3589x_reg_read(tc3589x, reg);
130 	if (ret < 0)
131 		goto out;
132 
133 	ret &= ~mask;
134 	ret |= val;
135 
136 	ret = tc3589x_reg_write(tc3589x, reg, ret);
137 
138 out:
139 	mutex_unlock(&tc3589x->lock);
140 	return ret;
141 }
142 EXPORT_SYMBOL_GPL(tc3589x_set_bits);
143 
144 static const struct resource gpio_resources[] = {
145 	{
146 		.start	= TC3589x_INT_GPIIRQ,
147 		.end	= TC3589x_INT_GPIIRQ,
148 		.flags	= IORESOURCE_IRQ,
149 	},
150 };
151 
152 static const struct resource keypad_resources[] = {
153 	{
154 		.start  = TC3589x_INT_KBDIRQ,
155 		.end    = TC3589x_INT_KBDIRQ,
156 		.flags  = IORESOURCE_IRQ,
157 	},
158 };
159 
160 static const struct mfd_cell tc3589x_dev_gpio[] = {
161 	{
162 		.name		= "tc3589x-gpio",
163 		.num_resources	= ARRAY_SIZE(gpio_resources),
164 		.resources	= &gpio_resources[0],
165 		.of_compatible	= "toshiba,tc3589x-gpio",
166 	},
167 };
168 
169 static const struct mfd_cell tc3589x_dev_keypad[] = {
170 	{
171 		.name           = "tc3589x-keypad",
172 		.num_resources  = ARRAY_SIZE(keypad_resources),
173 		.resources      = &keypad_resources[0],
174 		.of_compatible	= "toshiba,tc3589x-keypad",
175 	},
176 };
177 
tc3589x_irq(int irq,void * data)178 static irqreturn_t tc3589x_irq(int irq, void *data)
179 {
180 	struct tc3589x *tc3589x = data;
181 	int status;
182 
183 again:
184 	status = tc3589x_reg_read(tc3589x, TC3589x_IRQST);
185 	if (status < 0)
186 		return IRQ_NONE;
187 
188 	while (status) {
189 		int bit = __ffs(status);
190 		int virq = irq_find_mapping(tc3589x->domain, bit);
191 
192 		handle_nested_irq(virq);
193 		status &= ~(1 << bit);
194 	}
195 
196 	/*
197 	 * A dummy read or write (to any register) appears to be necessary to
198 	 * have the last interrupt clear (for example, GPIO IC write) take
199 	 * effect. In such a case, recheck for any interrupt which is still
200 	 * pending.
201 	 */
202 	status = tc3589x_reg_read(tc3589x, TC3589x_IRQST);
203 	if (status)
204 		goto again;
205 
206 	return IRQ_HANDLED;
207 }
208 
tc3589x_irq_map(struct irq_domain * d,unsigned int virq,irq_hw_number_t hwirq)209 static int tc3589x_irq_map(struct irq_domain *d, unsigned int virq,
210 				irq_hw_number_t hwirq)
211 {
212 	struct tc3589x *tc3589x = d->host_data;
213 
214 	irq_set_chip_data(virq, tc3589x);
215 	irq_set_chip_and_handler(virq, &dummy_irq_chip,
216 				handle_edge_irq);
217 	irq_set_nested_thread(virq, 1);
218 	irq_set_noprobe(virq);
219 
220 	return 0;
221 }
222 
tc3589x_irq_unmap(struct irq_domain * d,unsigned int virq)223 static void tc3589x_irq_unmap(struct irq_domain *d, unsigned int virq)
224 {
225 	irq_set_chip_and_handler(virq, NULL, NULL);
226 	irq_set_chip_data(virq, NULL);
227 }
228 
229 static const struct irq_domain_ops tc3589x_irq_ops = {
230 	.map    = tc3589x_irq_map,
231 	.unmap  = tc3589x_irq_unmap,
232 	.xlate  = irq_domain_xlate_onecell,
233 };
234 
tc3589x_irq_init(struct tc3589x * tc3589x,struct device_node * np)235 static int tc3589x_irq_init(struct tc3589x *tc3589x, struct device_node *np)
236 {
237 	tc3589x->domain = irq_domain_add_simple(
238 		np, TC3589x_NR_INTERNAL_IRQS, 0,
239 		&tc3589x_irq_ops, tc3589x);
240 
241 	if (!tc3589x->domain) {
242 		dev_err(tc3589x->dev, "Failed to create irqdomain\n");
243 		return -ENOSYS;
244 	}
245 
246 	return 0;
247 }
248 
tc3589x_chip_init(struct tc3589x * tc3589x)249 static int tc3589x_chip_init(struct tc3589x *tc3589x)
250 {
251 	int manf, ver, ret;
252 
253 	manf = tc3589x_reg_read(tc3589x, TC3589x_MANFCODE);
254 	if (manf < 0)
255 		return manf;
256 
257 	ver = tc3589x_reg_read(tc3589x, TC3589x_VERSION);
258 	if (ver < 0)
259 		return ver;
260 
261 	if (manf != TC3589x_MANFCODE_MAGIC) {
262 		dev_err(tc3589x->dev, "unknown manufacturer: %#x\n", manf);
263 		return -EINVAL;
264 	}
265 
266 	dev_info(tc3589x->dev, "manufacturer: %#x, version: %#x\n", manf, ver);
267 
268 	/*
269 	 * Put everything except the IRQ module into reset;
270 	 * also spare the GPIO module for any pin initialization
271 	 * done during pre-kernel boot
272 	 */
273 	ret = tc3589x_reg_write(tc3589x, TC3589x_RSTCTRL,
274 				TC3589x_RSTCTRL_TIMRST
275 				| TC3589x_RSTCTRL_ROTRST
276 				| TC3589x_RSTCTRL_KBDRST);
277 	if (ret < 0)
278 		return ret;
279 
280 	/* Clear the reset interrupt. */
281 	return tc3589x_reg_write(tc3589x, TC3589x_RSTINTCLR, 0x1);
282 }
283 
tc3589x_device_init(struct tc3589x * tc3589x)284 static int tc3589x_device_init(struct tc3589x *tc3589x)
285 {
286 	int ret = 0;
287 	unsigned int blocks = tc3589x->pdata->block;
288 
289 	if (blocks & TC3589x_BLOCK_GPIO) {
290 		ret = mfd_add_devices(tc3589x->dev, -1, tc3589x_dev_gpio,
291 				      ARRAY_SIZE(tc3589x_dev_gpio), NULL,
292 				      0, tc3589x->domain);
293 		if (ret) {
294 			dev_err(tc3589x->dev, "failed to add gpio child\n");
295 			return ret;
296 		}
297 		dev_info(tc3589x->dev, "added gpio block\n");
298 	}
299 
300 	if (blocks & TC3589x_BLOCK_KEYPAD) {
301 		ret = mfd_add_devices(tc3589x->dev, -1, tc3589x_dev_keypad,
302 				      ARRAY_SIZE(tc3589x_dev_keypad), NULL,
303 				      0, tc3589x->domain);
304 		if (ret) {
305 			dev_err(tc3589x->dev, "failed to keypad child\n");
306 			return ret;
307 		}
308 		dev_info(tc3589x->dev, "added keypad block\n");
309 	}
310 
311 	return ret;
312 }
313 
314 static const struct of_device_id tc3589x_match[] = {
315 	{ .compatible = "toshiba,tc35890", .data = (void *) TC3589X_TC35890 },
316 	{ .compatible = "toshiba,tc35892", .data = (void *) TC3589X_TC35892 },
317 	{ .compatible = "toshiba,tc35893", .data = (void *) TC3589X_TC35893 },
318 	{ .compatible = "toshiba,tc35894", .data = (void *) TC3589X_TC35894 },
319 	{ .compatible = "toshiba,tc35895", .data = (void *) TC3589X_TC35895 },
320 	{ .compatible = "toshiba,tc35896", .data = (void *) TC3589X_TC35896 },
321 	{ }
322 };
323 
324 MODULE_DEVICE_TABLE(of, tc3589x_match);
325 
326 static struct tc3589x_platform_data *
tc3589x_of_probe(struct device * dev,enum tc3589x_version * version)327 tc3589x_of_probe(struct device *dev, enum tc3589x_version *version)
328 {
329 	struct device_node *np = dev->of_node;
330 	struct tc3589x_platform_data *pdata;
331 	struct device_node *child;
332 	const struct of_device_id *of_id;
333 
334 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
335 	if (!pdata)
336 		return ERR_PTR(-ENOMEM);
337 
338 	of_id = of_match_device(tc3589x_match, dev);
339 	if (!of_id)
340 		return ERR_PTR(-ENODEV);
341 	*version = (uintptr_t) of_id->data;
342 
343 	for_each_child_of_node(np, child) {
344 		if (of_device_is_compatible(child, "toshiba,tc3589x-gpio"))
345 			pdata->block |= TC3589x_BLOCK_GPIO;
346 		if (of_device_is_compatible(child, "toshiba,tc3589x-keypad"))
347 			pdata->block |= TC3589x_BLOCK_KEYPAD;
348 	}
349 
350 	return pdata;
351 }
352 
tc3589x_probe(struct i2c_client * i2c)353 static int tc3589x_probe(struct i2c_client *i2c)
354 {
355 	const struct i2c_device_id *id = i2c_client_get_device_id(i2c);
356 	struct device_node *np = i2c->dev.of_node;
357 	struct tc3589x_platform_data *pdata = dev_get_platdata(&i2c->dev);
358 	struct tc3589x *tc3589x;
359 	enum tc3589x_version version;
360 	int ret;
361 
362 	if (!pdata) {
363 		pdata = tc3589x_of_probe(&i2c->dev, &version);
364 		if (IS_ERR(pdata)) {
365 			dev_err(&i2c->dev, "No platform data or DT found\n");
366 			return PTR_ERR(pdata);
367 		}
368 	} else {
369 		/* When not probing from device tree we have this ID */
370 		version = id->driver_data;
371 	}
372 
373 	if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA
374 				     | I2C_FUNC_SMBUS_I2C_BLOCK))
375 		return -EIO;
376 
377 	tc3589x = devm_kzalloc(&i2c->dev, sizeof(struct tc3589x),
378 				GFP_KERNEL);
379 	if (!tc3589x)
380 		return -ENOMEM;
381 
382 	mutex_init(&tc3589x->lock);
383 
384 	tc3589x->dev = &i2c->dev;
385 	tc3589x->i2c = i2c;
386 	tc3589x->pdata = pdata;
387 
388 	switch (version) {
389 	case TC3589X_TC35893:
390 	case TC3589X_TC35895:
391 	case TC3589X_TC35896:
392 		tc3589x->num_gpio = 20;
393 		break;
394 	case TC3589X_TC35890:
395 	case TC3589X_TC35892:
396 	case TC3589X_TC35894:
397 	case TC3589X_UNKNOWN:
398 	default:
399 		tc3589x->num_gpio = 24;
400 		break;
401 	}
402 
403 	i2c_set_clientdata(i2c, tc3589x);
404 
405 	ret = tc3589x_chip_init(tc3589x);
406 	if (ret)
407 		return ret;
408 
409 	ret = tc3589x_irq_init(tc3589x, np);
410 	if (ret)
411 		return ret;
412 
413 	ret = request_threaded_irq(tc3589x->i2c->irq, NULL, tc3589x_irq,
414 				   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
415 				   "tc3589x", tc3589x);
416 	if (ret) {
417 		dev_err(tc3589x->dev, "failed to request IRQ: %d\n", ret);
418 		return ret;
419 	}
420 
421 	ret = tc3589x_device_init(tc3589x);
422 	if (ret) {
423 		dev_err(tc3589x->dev, "failed to add child devices\n");
424 		return ret;
425 	}
426 
427 	return 0;
428 }
429 
tc3589x_remove(struct i2c_client * client)430 static void tc3589x_remove(struct i2c_client *client)
431 {
432 	struct tc3589x *tc3589x = i2c_get_clientdata(client);
433 
434 	mfd_remove_devices(tc3589x->dev);
435 }
436 
tc3589x_suspend(struct device * dev)437 static int tc3589x_suspend(struct device *dev)
438 {
439 	struct tc3589x *tc3589x = dev_get_drvdata(dev);
440 	struct i2c_client *client = tc3589x->i2c;
441 	int ret = 0;
442 
443 	/* put the system to sleep mode */
444 	if (!device_may_wakeup(&client->dev))
445 		ret = tc3589x_reg_write(tc3589x, TC3589x_CLKMODE,
446 				TC3589x_CLKMODE_MODCTL_SLEEP);
447 
448 	return ret;
449 }
450 
tc3589x_resume(struct device * dev)451 static int tc3589x_resume(struct device *dev)
452 {
453 	struct tc3589x *tc3589x = dev_get_drvdata(dev);
454 	struct i2c_client *client = tc3589x->i2c;
455 	int ret = 0;
456 
457 	/* enable the system into operation */
458 	if (!device_may_wakeup(&client->dev))
459 		ret = tc3589x_reg_write(tc3589x, TC3589x_CLKMODE,
460 				TC3589x_CLKMODE_MODCTL_OPERATION);
461 
462 	return ret;
463 }
464 
465 static DEFINE_SIMPLE_DEV_PM_OPS(tc3589x_dev_pm_ops,
466 				tc3589x_suspend, tc3589x_resume);
467 
468 static const struct i2c_device_id tc3589x_id[] = {
469 	{ "tc35890", TC3589X_TC35890 },
470 	{ "tc35892", TC3589X_TC35892 },
471 	{ "tc35893", TC3589X_TC35893 },
472 	{ "tc35894", TC3589X_TC35894 },
473 	{ "tc35895", TC3589X_TC35895 },
474 	{ "tc35896", TC3589X_TC35896 },
475 	{ "tc3589x", TC3589X_UNKNOWN },
476 	{ }
477 };
478 MODULE_DEVICE_TABLE(i2c, tc3589x_id);
479 
480 static struct i2c_driver tc3589x_driver = {
481 	.driver = {
482 		.name	= "tc3589x",
483 		.pm	= pm_sleep_ptr(&tc3589x_dev_pm_ops),
484 		.of_match_table = tc3589x_match,
485 	},
486 	.probe		= tc3589x_probe,
487 	.remove		= tc3589x_remove,
488 	.id_table	= tc3589x_id,
489 };
490 
tc3589x_init(void)491 static int __init tc3589x_init(void)
492 {
493 	return i2c_add_driver(&tc3589x_driver);
494 }
495 subsys_initcall(tc3589x_init);
496 
tc3589x_exit(void)497 static void __exit tc3589x_exit(void)
498 {
499 	i2c_del_driver(&tc3589x_driver);
500 }
501 module_exit(tc3589x_exit);
502 
503 MODULE_DESCRIPTION("TC3589x MFD core driver");
504 MODULE_AUTHOR("Hanumath Prasad, Rabin Vincent");
505