xref: /openbmc/linux/drivers/mfd/tc3589x.c (revision 089a49b6)
1 /*
2  * Copyright (C) ST-Ericsson SA 2010
3  *
4  * License Terms: GNU General Public License, version 2
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/mfd/core.h>
17 #include <linux/mfd/tc3589x.h>
18 
19 #define TC3589x_CLKMODE_MODCTL_SLEEP		0x0
20 #define TC3589x_CLKMODE_MODCTL_OPERATION	(1 << 0)
21 
22 /**
23  * tc3589x_reg_read() - read a single TC3589x register
24  * @tc3589x:	Device to read from
25  * @reg:	Register to read
26  */
27 int tc3589x_reg_read(struct tc3589x *tc3589x, u8 reg)
28 {
29 	int ret;
30 
31 	ret = i2c_smbus_read_byte_data(tc3589x->i2c, reg);
32 	if (ret < 0)
33 		dev_err(tc3589x->dev, "failed to read reg %#x: %d\n",
34 			reg, ret);
35 
36 	return ret;
37 }
38 EXPORT_SYMBOL_GPL(tc3589x_reg_read);
39 
40 /**
41  * tc3589x_reg_read() - write a single TC3589x register
42  * @tc3589x:	Device to write to
43  * @reg:	Register to read
44  * @data:	Value to write
45  */
46 int tc3589x_reg_write(struct tc3589x *tc3589x, u8 reg, u8 data)
47 {
48 	int ret;
49 
50 	ret = i2c_smbus_write_byte_data(tc3589x->i2c, reg, data);
51 	if (ret < 0)
52 		dev_err(tc3589x->dev, "failed to write reg %#x: %d\n",
53 			reg, ret);
54 
55 	return ret;
56 }
57 EXPORT_SYMBOL_GPL(tc3589x_reg_write);
58 
59 /**
60  * tc3589x_block_read() - read multiple TC3589x registers
61  * @tc3589x:	Device to read from
62  * @reg:	First register
63  * @length:	Number of registers
64  * @values:	Buffer to write to
65  */
66 int tc3589x_block_read(struct tc3589x *tc3589x, u8 reg, u8 length, u8 *values)
67 {
68 	int ret;
69 
70 	ret = i2c_smbus_read_i2c_block_data(tc3589x->i2c, reg, length, values);
71 	if (ret < 0)
72 		dev_err(tc3589x->dev, "failed to read regs %#x: %d\n",
73 			reg, ret);
74 
75 	return ret;
76 }
77 EXPORT_SYMBOL_GPL(tc3589x_block_read);
78 
79 /**
80  * tc3589x_block_write() - write multiple TC3589x registers
81  * @tc3589x:	Device to write to
82  * @reg:	First register
83  * @length:	Number of registers
84  * @values:	Values to write
85  */
86 int tc3589x_block_write(struct tc3589x *tc3589x, u8 reg, u8 length,
87 			const u8 *values)
88 {
89 	int ret;
90 
91 	ret = i2c_smbus_write_i2c_block_data(tc3589x->i2c, reg, length,
92 					     values);
93 	if (ret < 0)
94 		dev_err(tc3589x->dev, "failed to write regs %#x: %d\n",
95 			reg, ret);
96 
97 	return ret;
98 }
99 EXPORT_SYMBOL_GPL(tc3589x_block_write);
100 
101 /**
102  * tc3589x_set_bits() - set the value of a bitfield in a TC3589x register
103  * @tc3589x:	Device to write to
104  * @reg:	Register to write
105  * @mask:	Mask of bits to set
106  * @values:	Value to set
107  */
108 int tc3589x_set_bits(struct tc3589x *tc3589x, u8 reg, u8 mask, u8 val)
109 {
110 	int ret;
111 
112 	mutex_lock(&tc3589x->lock);
113 
114 	ret = tc3589x_reg_read(tc3589x, reg);
115 	if (ret < 0)
116 		goto out;
117 
118 	ret &= ~mask;
119 	ret |= val;
120 
121 	ret = tc3589x_reg_write(tc3589x, reg, ret);
122 
123 out:
124 	mutex_unlock(&tc3589x->lock);
125 	return ret;
126 }
127 EXPORT_SYMBOL_GPL(tc3589x_set_bits);
128 
129 static struct resource gpio_resources[] = {
130 	{
131 		.start	= TC3589x_INT_GPIIRQ,
132 		.end	= TC3589x_INT_GPIIRQ,
133 		.flags	= IORESOURCE_IRQ,
134 	},
135 };
136 
137 static struct resource keypad_resources[] = {
138 	{
139 		.start  = TC3589x_INT_KBDIRQ,
140 		.end    = TC3589x_INT_KBDIRQ,
141 		.flags  = IORESOURCE_IRQ,
142 	},
143 };
144 
145 static struct mfd_cell tc3589x_dev_gpio[] = {
146 	{
147 		.name		= "tc3589x-gpio",
148 		.num_resources	= ARRAY_SIZE(gpio_resources),
149 		.resources	= &gpio_resources[0],
150 		.of_compatible	= "tc3589x-gpio",
151 	},
152 };
153 
154 static struct mfd_cell tc3589x_dev_keypad[] = {
155 	{
156 		.name           = "tc3589x-keypad",
157 		.num_resources  = ARRAY_SIZE(keypad_resources),
158 		.resources      = &keypad_resources[0],
159 		.of_compatible	= "tc3589x-keypad",
160 	},
161 };
162 
163 static irqreturn_t tc3589x_irq(int irq, void *data)
164 {
165 	struct tc3589x *tc3589x = data;
166 	int status;
167 
168 again:
169 	status = tc3589x_reg_read(tc3589x, TC3589x_IRQST);
170 	if (status < 0)
171 		return IRQ_NONE;
172 
173 	while (status) {
174 		int bit = __ffs(status);
175 		int virq = irq_create_mapping(tc3589x->domain, bit);
176 
177 		handle_nested_irq(virq);
178 		status &= ~(1 << bit);
179 	}
180 
181 	/*
182 	 * A dummy read or write (to any register) appears to be necessary to
183 	 * have the last interrupt clear (for example, GPIO IC write) take
184 	 * effect. In such a case, recheck for any interrupt which is still
185 	 * pending.
186 	 */
187 	status = tc3589x_reg_read(tc3589x, TC3589x_IRQST);
188 	if (status)
189 		goto again;
190 
191 	return IRQ_HANDLED;
192 }
193 
194 static int tc3589x_irq_map(struct irq_domain *d, unsigned int virq,
195 				irq_hw_number_t hwirq)
196 {
197 	struct tc3589x *tc3589x = d->host_data;
198 
199 	irq_set_chip_data(virq, tc3589x);
200 	irq_set_chip_and_handler(virq, &dummy_irq_chip,
201 				handle_edge_irq);
202 	irq_set_nested_thread(virq, 1);
203 #ifdef CONFIG_ARM
204 	set_irq_flags(virq, IRQF_VALID);
205 #else
206 	irq_set_noprobe(virq);
207 #endif
208 
209 	return 0;
210 }
211 
212 static void tc3589x_irq_unmap(struct irq_domain *d, unsigned int virq)
213 {
214 #ifdef CONFIG_ARM
215 	set_irq_flags(virq, 0);
216 #endif
217 	irq_set_chip_and_handler(virq, NULL, NULL);
218 	irq_set_chip_data(virq, NULL);
219 }
220 
221 static struct irq_domain_ops tc3589x_irq_ops = {
222 	.map    = tc3589x_irq_map,
223 	.unmap  = tc3589x_irq_unmap,
224 	.xlate  = irq_domain_xlate_twocell,
225 };
226 
227 static int tc3589x_irq_init(struct tc3589x *tc3589x, struct device_node *np)
228 {
229 	int base = tc3589x->irq_base;
230 
231 	tc3589x->domain = irq_domain_add_simple(
232 		np, TC3589x_NR_INTERNAL_IRQS, base,
233 		&tc3589x_irq_ops, tc3589x);
234 
235 	if (!tc3589x->domain) {
236 		dev_err(tc3589x->dev, "Failed to create irqdomain\n");
237 		return -ENOSYS;
238 	}
239 
240 	return 0;
241 }
242 
243 static int tc3589x_chip_init(struct tc3589x *tc3589x)
244 {
245 	int manf, ver, ret;
246 
247 	manf = tc3589x_reg_read(tc3589x, TC3589x_MANFCODE);
248 	if (manf < 0)
249 		return manf;
250 
251 	ver = tc3589x_reg_read(tc3589x, TC3589x_VERSION);
252 	if (ver < 0)
253 		return ver;
254 
255 	if (manf != TC3589x_MANFCODE_MAGIC) {
256 		dev_err(tc3589x->dev, "unknown manufacturer: %#x\n", manf);
257 		return -EINVAL;
258 	}
259 
260 	dev_info(tc3589x->dev, "manufacturer: %#x, version: %#x\n", manf, ver);
261 
262 	/*
263 	 * Put everything except the IRQ module into reset;
264 	 * also spare the GPIO module for any pin initialization
265 	 * done during pre-kernel boot
266 	 */
267 	ret = tc3589x_reg_write(tc3589x, TC3589x_RSTCTRL,
268 				TC3589x_RSTCTRL_TIMRST
269 				| TC3589x_RSTCTRL_ROTRST
270 				| TC3589x_RSTCTRL_KBDRST);
271 	if (ret < 0)
272 		return ret;
273 
274 	/* Clear the reset interrupt. */
275 	return tc3589x_reg_write(tc3589x, TC3589x_RSTINTCLR, 0x1);
276 }
277 
278 static int tc3589x_device_init(struct tc3589x *tc3589x)
279 {
280 	int ret = 0;
281 	unsigned int blocks = tc3589x->pdata->block;
282 
283 	if (blocks & TC3589x_BLOCK_GPIO) {
284 		ret = mfd_add_devices(tc3589x->dev, -1, tc3589x_dev_gpio,
285 				      ARRAY_SIZE(tc3589x_dev_gpio), NULL,
286 				      tc3589x->irq_base, tc3589x->domain);
287 		if (ret) {
288 			dev_err(tc3589x->dev, "failed to add gpio child\n");
289 			return ret;
290 		}
291 		dev_info(tc3589x->dev, "added gpio block\n");
292 	}
293 
294 	if (blocks & TC3589x_BLOCK_KEYPAD) {
295 		ret = mfd_add_devices(tc3589x->dev, -1, tc3589x_dev_keypad,
296 				      ARRAY_SIZE(tc3589x_dev_keypad), NULL,
297 				      tc3589x->irq_base, tc3589x->domain);
298 		if (ret) {
299 			dev_err(tc3589x->dev, "failed to keypad child\n");
300 			return ret;
301 		}
302 		dev_info(tc3589x->dev, "added keypad block\n");
303 	}
304 
305 	return ret;
306 }
307 
308 static int tc3589x_of_probe(struct device_node *np,
309 			struct tc3589x_platform_data *pdata)
310 {
311 	struct device_node *child;
312 
313 	for_each_child_of_node(np, child) {
314 		if (!strcmp(child->name, "tc3589x_gpio")) {
315 			pdata->block |= TC3589x_BLOCK_GPIO;
316 		}
317 		if (!strcmp(child->name, "tc3589x_keypad")) {
318 			pdata->block |= TC3589x_BLOCK_KEYPAD;
319 		}
320 	}
321 
322 	return 0;
323 }
324 
325 static int tc3589x_probe(struct i2c_client *i2c,
326 				   const struct i2c_device_id *id)
327 {
328 	struct tc3589x_platform_data *pdata = dev_get_platdata(&i2c->dev);
329 	struct device_node *np = i2c->dev.of_node;
330 	struct tc3589x *tc3589x;
331 	int ret;
332 
333 	if (!pdata) {
334 		if (np) {
335 			pdata = devm_kzalloc(&i2c->dev, sizeof(*pdata), GFP_KERNEL);
336 			if (!pdata)
337 				return -ENOMEM;
338 
339 			ret = tc3589x_of_probe(np, pdata);
340 			if (ret)
341 				return ret;
342 		}
343 		else {
344 			dev_err(&i2c->dev, "No platform data or DT found\n");
345 			return -EINVAL;
346 		}
347 	}
348 
349 	if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA
350 				     | I2C_FUNC_SMBUS_I2C_BLOCK))
351 		return -EIO;
352 
353 	tc3589x = devm_kzalloc(&i2c->dev, sizeof(struct tc3589x),
354 				GFP_KERNEL);
355 	if (!tc3589x)
356 		return -ENOMEM;
357 
358 	mutex_init(&tc3589x->lock);
359 
360 	tc3589x->dev = &i2c->dev;
361 	tc3589x->i2c = i2c;
362 	tc3589x->pdata = pdata;
363 	tc3589x->irq_base = pdata->irq_base;
364 	tc3589x->num_gpio = id->driver_data;
365 
366 	i2c_set_clientdata(i2c, tc3589x);
367 
368 	ret = tc3589x_chip_init(tc3589x);
369 	if (ret)
370 		return ret;
371 
372 	ret = tc3589x_irq_init(tc3589x, np);
373 	if (ret)
374 		return ret;
375 
376 	ret = request_threaded_irq(tc3589x->i2c->irq, NULL, tc3589x_irq,
377 				   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
378 				   "tc3589x", tc3589x);
379 	if (ret) {
380 		dev_err(tc3589x->dev, "failed to request IRQ: %d\n", ret);
381 		return ret;
382 	}
383 
384 	ret = tc3589x_device_init(tc3589x);
385 	if (ret) {
386 		dev_err(tc3589x->dev, "failed to add child devices\n");
387 		return ret;
388 	}
389 
390 	return 0;
391 }
392 
393 static int tc3589x_remove(struct i2c_client *client)
394 {
395 	struct tc3589x *tc3589x = i2c_get_clientdata(client);
396 
397 	mfd_remove_devices(tc3589x->dev);
398 
399 	return 0;
400 }
401 
402 #ifdef CONFIG_PM_SLEEP
403 static int tc3589x_suspend(struct device *dev)
404 {
405 	struct tc3589x *tc3589x = dev_get_drvdata(dev);
406 	struct i2c_client *client = tc3589x->i2c;
407 	int ret = 0;
408 
409 	/* put the system to sleep mode */
410 	if (!device_may_wakeup(&client->dev))
411 		ret = tc3589x_reg_write(tc3589x, TC3589x_CLKMODE,
412 				TC3589x_CLKMODE_MODCTL_SLEEP);
413 
414 	return ret;
415 }
416 
417 static int tc3589x_resume(struct device *dev)
418 {
419 	struct tc3589x *tc3589x = dev_get_drvdata(dev);
420 	struct i2c_client *client = tc3589x->i2c;
421 	int ret = 0;
422 
423 	/* enable the system into operation */
424 	if (!device_may_wakeup(&client->dev))
425 		ret = tc3589x_reg_write(tc3589x, TC3589x_CLKMODE,
426 				TC3589x_CLKMODE_MODCTL_OPERATION);
427 
428 	return ret;
429 }
430 #endif
431 
432 static SIMPLE_DEV_PM_OPS(tc3589x_dev_pm_ops, tc3589x_suspend, tc3589x_resume);
433 
434 static const struct i2c_device_id tc3589x_id[] = {
435 	{ "tc3589x", 24 },
436 	{ }
437 };
438 MODULE_DEVICE_TABLE(i2c, tc3589x_id);
439 
440 static struct i2c_driver tc3589x_driver = {
441 	.driver.name	= "tc3589x",
442 	.driver.owner	= THIS_MODULE,
443 	.driver.pm	= &tc3589x_dev_pm_ops,
444 	.probe		= tc3589x_probe,
445 	.remove		= tc3589x_remove,
446 	.id_table	= tc3589x_id,
447 };
448 
449 static int __init tc3589x_init(void)
450 {
451 	return i2c_add_driver(&tc3589x_driver);
452 }
453 subsys_initcall(tc3589x_init);
454 
455 static void __exit tc3589x_exit(void)
456 {
457 	i2c_del_driver(&tc3589x_driver);
458 }
459 module_exit(tc3589x_exit);
460 
461 MODULE_LICENSE("GPL v2");
462 MODULE_DESCRIPTION("TC3589x MFD core driver");
463 MODULE_AUTHOR("Hanumath Prasad, Rabin Vincent");
464