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/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 */
24enum 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 */
42int 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}
53EXPORT_SYMBOL_GPL(tc3589x_reg_read);
54
55/**
56 * tc3589x_reg_read() - write a single TC3589x register
57 * @tc3589x:	Device to write to
58 * @reg:	Register to read
59 * @data:	Value to write
60 */
61int 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}
72EXPORT_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 */
81int 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}
92EXPORT_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 */
101int 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}
114EXPORT_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 * @values:	Value to set
122 */
123int 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
138out:
139	mutex_unlock(&tc3589x->lock);
140	return ret;
141}
142EXPORT_SYMBOL_GPL(tc3589x_set_bits);
143
144static struct resource gpio_resources[] = {
145	{
146		.start	= TC3589x_INT_GPIIRQ,
147		.end	= TC3589x_INT_GPIIRQ,
148		.flags	= IORESOURCE_IRQ,
149	},
150};
151
152static struct resource keypad_resources[] = {
153	{
154		.start  = TC3589x_INT_KBDIRQ,
155		.end    = TC3589x_INT_KBDIRQ,
156		.flags  = IORESOURCE_IRQ,
157	},
158};
159
160static 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
169static 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
178static irqreturn_t tc3589x_irq(int irq, void *data)
179{
180	struct tc3589x *tc3589x = data;
181	int status;
182
183again:
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_create_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
209static 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#ifdef CONFIG_ARM
219	set_irq_flags(virq, IRQF_VALID);
220#else
221	irq_set_noprobe(virq);
222#endif
223
224	return 0;
225}
226
227static void tc3589x_irq_unmap(struct irq_domain *d, unsigned int virq)
228{
229#ifdef CONFIG_ARM
230	set_irq_flags(virq, 0);
231#endif
232	irq_set_chip_and_handler(virq, NULL, NULL);
233	irq_set_chip_data(virq, NULL);
234}
235
236static struct irq_domain_ops tc3589x_irq_ops = {
237	.map    = tc3589x_irq_map,
238	.unmap  = tc3589x_irq_unmap,
239	.xlate  = irq_domain_xlate_onecell,
240};
241
242static int tc3589x_irq_init(struct tc3589x *tc3589x, struct device_node *np)
243{
244	tc3589x->domain = irq_domain_add_simple(
245		np, TC3589x_NR_INTERNAL_IRQS, 0,
246		&tc3589x_irq_ops, tc3589x);
247
248	if (!tc3589x->domain) {
249		dev_err(tc3589x->dev, "Failed to create irqdomain\n");
250		return -ENOSYS;
251	}
252
253	return 0;
254}
255
256static int tc3589x_chip_init(struct tc3589x *tc3589x)
257{
258	int manf, ver, ret;
259
260	manf = tc3589x_reg_read(tc3589x, TC3589x_MANFCODE);
261	if (manf < 0)
262		return manf;
263
264	ver = tc3589x_reg_read(tc3589x, TC3589x_VERSION);
265	if (ver < 0)
266		return ver;
267
268	if (manf != TC3589x_MANFCODE_MAGIC) {
269		dev_err(tc3589x->dev, "unknown manufacturer: %#x\n", manf);
270		return -EINVAL;
271	}
272
273	dev_info(tc3589x->dev, "manufacturer: %#x, version: %#x\n", manf, ver);
274
275	/*
276	 * Put everything except the IRQ module into reset;
277	 * also spare the GPIO module for any pin initialization
278	 * done during pre-kernel boot
279	 */
280	ret = tc3589x_reg_write(tc3589x, TC3589x_RSTCTRL,
281				TC3589x_RSTCTRL_TIMRST
282				| TC3589x_RSTCTRL_ROTRST
283				| TC3589x_RSTCTRL_KBDRST);
284	if (ret < 0)
285		return ret;
286
287	/* Clear the reset interrupt. */
288	return tc3589x_reg_write(tc3589x, TC3589x_RSTINTCLR, 0x1);
289}
290
291static int tc3589x_device_init(struct tc3589x *tc3589x)
292{
293	int ret = 0;
294	unsigned int blocks = tc3589x->pdata->block;
295
296	if (blocks & TC3589x_BLOCK_GPIO) {
297		ret = mfd_add_devices(tc3589x->dev, -1, tc3589x_dev_gpio,
298				      ARRAY_SIZE(tc3589x_dev_gpio), NULL,
299				      0, tc3589x->domain);
300		if (ret) {
301			dev_err(tc3589x->dev, "failed to add gpio child\n");
302			return ret;
303		}
304		dev_info(tc3589x->dev, "added gpio block\n");
305	}
306
307	if (blocks & TC3589x_BLOCK_KEYPAD) {
308		ret = mfd_add_devices(tc3589x->dev, -1, tc3589x_dev_keypad,
309				      ARRAY_SIZE(tc3589x_dev_keypad), NULL,
310				      0, tc3589x->domain);
311		if (ret) {
312			dev_err(tc3589x->dev, "failed to keypad child\n");
313			return ret;
314		}
315		dev_info(tc3589x->dev, "added keypad block\n");
316	}
317
318	return ret;
319}
320
321static const struct of_device_id tc3589x_match[] = {
322	/* Legacy compatible string */
323	{ .compatible = "tc3589x", .data = (void *) TC3589X_UNKNOWN },
324	{ .compatible = "toshiba,tc35890", .data = (void *) TC3589X_TC35890 },
325	{ .compatible = "toshiba,tc35892", .data = (void *) TC3589X_TC35892 },
326	{ .compatible = "toshiba,tc35893", .data = (void *) TC3589X_TC35893 },
327	{ .compatible = "toshiba,tc35894", .data = (void *) TC3589X_TC35894 },
328	{ .compatible = "toshiba,tc35895", .data = (void *) TC3589X_TC35895 },
329	{ .compatible = "toshiba,tc35896", .data = (void *) TC3589X_TC35896 },
330	{ }
331};
332
333MODULE_DEVICE_TABLE(of, tc3589x_match);
334
335static struct tc3589x_platform_data *
336tc3589x_of_probe(struct device *dev, enum tc3589x_version *version)
337{
338	struct device_node *np = dev->of_node;
339	struct tc3589x_platform_data *pdata;
340	struct device_node *child;
341	const struct of_device_id *of_id;
342
343	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
344	if (!pdata)
345		return ERR_PTR(-ENOMEM);
346
347	of_id = of_match_device(tc3589x_match, dev);
348	if (!of_id)
349		return ERR_PTR(-ENODEV);
350	*version = (enum tc3589x_version) of_id->data;
351
352	for_each_child_of_node(np, child) {
353		if (of_device_is_compatible(child, "toshiba,tc3589x-gpio"))
354			pdata->block |= TC3589x_BLOCK_GPIO;
355		if (of_device_is_compatible(child, "toshiba,tc3589x-keypad"))
356			pdata->block |= TC3589x_BLOCK_KEYPAD;
357	}
358
359	return pdata;
360}
361
362static int tc3589x_probe(struct i2c_client *i2c,
363				   const struct i2c_device_id *id)
364{
365	struct device_node *np = i2c->dev.of_node;
366	struct tc3589x_platform_data *pdata = dev_get_platdata(&i2c->dev);
367	struct tc3589x *tc3589x;
368	enum tc3589x_version version;
369	int ret;
370
371	if (!pdata) {
372		pdata = tc3589x_of_probe(&i2c->dev, &version);
373		if (IS_ERR(pdata)) {
374			dev_err(&i2c->dev, "No platform data or DT found\n");
375			return PTR_ERR(pdata);
376		}
377	} else {
378		/* When not probing from device tree we have this ID */
379		version = id->driver_data;
380	}
381
382	if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA
383				     | I2C_FUNC_SMBUS_I2C_BLOCK))
384		return -EIO;
385
386	tc3589x = devm_kzalloc(&i2c->dev, sizeof(struct tc3589x),
387				GFP_KERNEL);
388	if (!tc3589x)
389		return -ENOMEM;
390
391	mutex_init(&tc3589x->lock);
392
393	tc3589x->dev = &i2c->dev;
394	tc3589x->i2c = i2c;
395	tc3589x->pdata = pdata;
396
397	switch (version) {
398	case TC3589X_TC35893:
399	case TC3589X_TC35895:
400	case TC3589X_TC35896:
401		tc3589x->num_gpio = 20;
402		break;
403	case TC3589X_TC35890:
404	case TC3589X_TC35892:
405	case TC3589X_TC35894:
406	case TC3589X_UNKNOWN:
407	default:
408		tc3589x->num_gpio = 24;
409		break;
410	}
411
412	i2c_set_clientdata(i2c, tc3589x);
413
414	ret = tc3589x_chip_init(tc3589x);
415	if (ret)
416		return ret;
417
418	ret = tc3589x_irq_init(tc3589x, np);
419	if (ret)
420		return ret;
421
422	ret = request_threaded_irq(tc3589x->i2c->irq, NULL, tc3589x_irq,
423				   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
424				   "tc3589x", tc3589x);
425	if (ret) {
426		dev_err(tc3589x->dev, "failed to request IRQ: %d\n", ret);
427		return ret;
428	}
429
430	ret = tc3589x_device_init(tc3589x);
431	if (ret) {
432		dev_err(tc3589x->dev, "failed to add child devices\n");
433		return ret;
434	}
435
436	return 0;
437}
438
439static int tc3589x_remove(struct i2c_client *client)
440{
441	struct tc3589x *tc3589x = i2c_get_clientdata(client);
442
443	mfd_remove_devices(tc3589x->dev);
444
445	return 0;
446}
447
448#ifdef CONFIG_PM_SLEEP
449static int tc3589x_suspend(struct device *dev)
450{
451	struct tc3589x *tc3589x = dev_get_drvdata(dev);
452	struct i2c_client *client = tc3589x->i2c;
453	int ret = 0;
454
455	/* put the system to sleep mode */
456	if (!device_may_wakeup(&client->dev))
457		ret = tc3589x_reg_write(tc3589x, TC3589x_CLKMODE,
458				TC3589x_CLKMODE_MODCTL_SLEEP);
459
460	return ret;
461}
462
463static int tc3589x_resume(struct device *dev)
464{
465	struct tc3589x *tc3589x = dev_get_drvdata(dev);
466	struct i2c_client *client = tc3589x->i2c;
467	int ret = 0;
468
469	/* enable the system into operation */
470	if (!device_may_wakeup(&client->dev))
471		ret = tc3589x_reg_write(tc3589x, TC3589x_CLKMODE,
472				TC3589x_CLKMODE_MODCTL_OPERATION);
473
474	return ret;
475}
476#endif
477
478static SIMPLE_DEV_PM_OPS(tc3589x_dev_pm_ops, tc3589x_suspend, tc3589x_resume);
479
480static const struct i2c_device_id tc3589x_id[] = {
481	{ "tc35890", TC3589X_TC35890 },
482	{ "tc35892", TC3589X_TC35892 },
483	{ "tc35893", TC3589X_TC35893 },
484	{ "tc35894", TC3589X_TC35894 },
485	{ "tc35895", TC3589X_TC35895 },
486	{ "tc35896", TC3589X_TC35896 },
487	{ "tc3589x", TC3589X_UNKNOWN },
488	{ }
489};
490MODULE_DEVICE_TABLE(i2c, tc3589x_id);
491
492static struct i2c_driver tc3589x_driver = {
493	.driver = {
494		.name	= "tc3589x",
495		.owner	= THIS_MODULE,
496		.pm	= &tc3589x_dev_pm_ops,
497		.of_match_table = of_match_ptr(tc3589x_match),
498	},
499	.probe		= tc3589x_probe,
500	.remove		= tc3589x_remove,
501	.id_table	= tc3589x_id,
502};
503
504static int __init tc3589x_init(void)
505{
506	return i2c_add_driver(&tc3589x_driver);
507}
508subsys_initcall(tc3589x_init);
509
510static void __exit tc3589x_exit(void)
511{
512	i2c_del_driver(&tc3589x_driver);
513}
514module_exit(tc3589x_exit);
515
516MODULE_LICENSE("GPL v2");
517MODULE_DESCRIPTION("TC3589x MFD core driver");
518MODULE_AUTHOR("Hanumath Prasad, Rabin Vincent");
519