1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * extcon-fsa9480.c - Fairchild Semiconductor FSA9480 extcon driver
4 *
5 * Copyright (c) 2019 Tomasz Figa <tomasz.figa@gmail.com>
6 *
7 * Loosely based on old fsa9480 misc-device driver.
8 */
9
10#include <linux/kernel.h>
11#include <linux/module.h>
12#include <linux/types.h>
13#include <linux/i2c.h>
14#include <linux/slab.h>
15#include <linux/bitops.h>
16#include <linux/interrupt.h>
17#include <linux/err.h>
18#include <linux/platform_device.h>
19#include <linux/kobject.h>
20#include <linux/extcon-provider.h>
21#include <linux/irqdomain.h>
22#include <linux/regmap.h>
23
24/* FSA9480 I2C registers */
25#define FSA9480_REG_DEVID               0x01
26#define FSA9480_REG_CTRL                0x02
27#define FSA9480_REG_INT1                0x03
28#define FSA9480_REG_INT2                0x04
29#define FSA9480_REG_INT1_MASK           0x05
30#define FSA9480_REG_INT2_MASK           0x06
31#define FSA9480_REG_ADC                 0x07
32#define FSA9480_REG_TIMING1             0x08
33#define FSA9480_REG_TIMING2             0x09
34#define FSA9480_REG_DEV_T1              0x0a
35#define FSA9480_REG_DEV_T2              0x0b
36#define FSA9480_REG_BTN1                0x0c
37#define FSA9480_REG_BTN2                0x0d
38#define FSA9480_REG_CK                  0x0e
39#define FSA9480_REG_CK_INT1             0x0f
40#define FSA9480_REG_CK_INT2             0x10
41#define FSA9480_REG_CK_INTMASK1         0x11
42#define FSA9480_REG_CK_INTMASK2         0x12
43#define FSA9480_REG_MANSW1              0x13
44#define FSA9480_REG_MANSW2              0x14
45#define FSA9480_REG_END                 0x15
46
47/* Control */
48#define CON_SWITCH_OPEN         (1 << 4)
49#define CON_RAW_DATA            (1 << 3)
50#define CON_MANUAL_SW           (1 << 2)
51#define CON_WAIT                (1 << 1)
52#define CON_INT_MASK            (1 << 0)
53#define CON_MASK                (CON_SWITCH_OPEN | CON_RAW_DATA | \
54				 CON_MANUAL_SW | CON_WAIT)
55
56/* Device Type 1 */
57#define DEV_USB_OTG             7
58#define DEV_DEDICATED_CHG       6
59#define DEV_USB_CHG             5
60#define DEV_CAR_KIT             4
61#define DEV_UART                3
62#define DEV_USB                 2
63#define DEV_AUDIO_2             1
64#define DEV_AUDIO_1             0
65
66#define DEV_T1_USB_MASK         (DEV_USB_OTG | DEV_USB)
67#define DEV_T1_UART_MASK        (DEV_UART)
68#define DEV_T1_CHARGER_MASK     (DEV_DEDICATED_CHG | DEV_USB_CHG)
69
70/* Device Type 2 */
71#define DEV_AV                  14
72#define DEV_TTY                 13
73#define DEV_PPD                 12
74#define DEV_JIG_UART_OFF        11
75#define DEV_JIG_UART_ON         10
76#define DEV_JIG_USB_OFF         9
77#define DEV_JIG_USB_ON          8
78
79#define DEV_T2_USB_MASK         (DEV_JIG_USB_OFF | DEV_JIG_USB_ON)
80#define DEV_T2_UART_MASK        (DEV_JIG_UART_OFF | DEV_JIG_UART_ON)
81#define DEV_T2_JIG_MASK         (DEV_JIG_USB_OFF | DEV_JIG_USB_ON | \
82				 DEV_JIG_UART_OFF | DEV_JIG_UART_ON)
83
84/*
85 * Manual Switch
86 * D- [7:5] / D+ [4:2]
87 * 000: Open all / 001: USB / 010: AUDIO / 011: UART / 100: V_AUDIO
88 */
89#define SW_VAUDIO               ((4 << 5) | (4 << 2))
90#define SW_UART                 ((3 << 5) | (3 << 2))
91#define SW_AUDIO                ((2 << 5) | (2 << 2))
92#define SW_DHOST                ((1 << 5) | (1 << 2))
93#define SW_AUTO                 ((0 << 5) | (0 << 2))
94
95/* Interrupt 1 */
96#define INT1_MASK               (0xff << 0)
97#define INT_DETACH              (1 << 1)
98#define INT_ATTACH              (1 << 0)
99
100/* Interrupt 2 mask */
101#define INT2_MASK               (0x1f << 0)
102
103/* Timing Set 1 */
104#define TIMING1_ADC_500MS       (0x6 << 0)
105
106struct fsa9480_usbsw {
107	struct device *dev;
108	struct regmap *regmap;
109	struct extcon_dev *edev;
110	u16 cable;
111};
112
113static const unsigned int fsa9480_extcon_cable[] = {
114	EXTCON_USB_HOST,
115	EXTCON_USB,
116	EXTCON_CHG_USB_DCP,
117	EXTCON_CHG_USB_SDP,
118	EXTCON_CHG_USB_ACA,
119	EXTCON_JACK_LINE_OUT,
120	EXTCON_JACK_VIDEO_OUT,
121	EXTCON_JIG,
122
123	EXTCON_NONE,
124};
125
126static const u64 cable_types[] = {
127	[DEV_USB_OTG] = BIT_ULL(EXTCON_USB_HOST),
128	[DEV_DEDICATED_CHG] = BIT_ULL(EXTCON_USB) | BIT_ULL(EXTCON_CHG_USB_DCP),
129	[DEV_USB_CHG] = BIT_ULL(EXTCON_USB) | BIT_ULL(EXTCON_CHG_USB_SDP),
130	[DEV_CAR_KIT] = BIT_ULL(EXTCON_USB) | BIT_ULL(EXTCON_CHG_USB_SDP)
131			| BIT_ULL(EXTCON_JACK_LINE_OUT),
132	[DEV_UART] = BIT_ULL(EXTCON_JIG),
133	[DEV_USB] = BIT_ULL(EXTCON_USB) | BIT_ULL(EXTCON_CHG_USB_SDP),
134	[DEV_AUDIO_2] = BIT_ULL(EXTCON_JACK_LINE_OUT),
135	[DEV_AUDIO_1] = BIT_ULL(EXTCON_JACK_LINE_OUT),
136	[DEV_AV] = BIT_ULL(EXTCON_JACK_LINE_OUT)
137		   | BIT_ULL(EXTCON_JACK_VIDEO_OUT),
138	[DEV_TTY] = BIT_ULL(EXTCON_JIG),
139	[DEV_PPD] = BIT_ULL(EXTCON_JACK_LINE_OUT) | BIT_ULL(EXTCON_CHG_USB_ACA),
140	[DEV_JIG_UART_OFF] = BIT_ULL(EXTCON_JIG),
141	[DEV_JIG_UART_ON] = BIT_ULL(EXTCON_JIG),
142	[DEV_JIG_USB_OFF] = BIT_ULL(EXTCON_USB) | BIT_ULL(EXTCON_JIG),
143	[DEV_JIG_USB_ON] = BIT_ULL(EXTCON_USB) | BIT_ULL(EXTCON_JIG),
144};
145
146/* Define regmap configuration of FSA9480 for I2C communication  */
147static bool fsa9480_volatile_reg(struct device *dev, unsigned int reg)
148{
149	switch (reg) {
150	case FSA9480_REG_INT1_MASK:
151		return true;
152	default:
153		break;
154	}
155	return false;
156}
157
158static const struct regmap_config fsa9480_regmap_config = {
159	.reg_bits	= 8,
160	.val_bits	= 8,
161	.volatile_reg	= fsa9480_volatile_reg,
162	.max_register	= FSA9480_REG_END,
163};
164
165static int fsa9480_write_reg(struct fsa9480_usbsw *usbsw, int reg, int value)
166{
167	int ret;
168
169	ret = regmap_write(usbsw->regmap, reg, value);
170	if (ret < 0)
171		dev_err(usbsw->dev, "%s: err %d\n", __func__, ret);
172
173	return ret;
174}
175
176static int fsa9480_read_reg(struct fsa9480_usbsw *usbsw, int reg)
177{
178	int ret, val;
179
180	ret = regmap_read(usbsw->regmap, reg, &val);
181	if (ret < 0) {
182		dev_err(usbsw->dev, "%s: err %d\n", __func__, ret);
183		return ret;
184	}
185
186	return val;
187}
188
189static int fsa9480_read_irq(struct fsa9480_usbsw *usbsw, int *value)
190{
191	u8 regs[2];
192	int ret;
193
194	ret = regmap_bulk_read(usbsw->regmap, FSA9480_REG_INT1, regs, 2);
195	if (ret < 0)
196		dev_err(usbsw->dev, "%s: err %d\n", __func__, ret);
197
198	*value = regs[1] << 8 | regs[0];
199	return ret;
200}
201
202static void fsa9480_handle_change(struct fsa9480_usbsw *usbsw,
203				  u16 mask, bool attached)
204{
205	while (mask) {
206		int dev = fls64(mask) - 1;
207		u64 cables = cable_types[dev];
208
209		while (cables) {
210			int cable = fls64(cables) - 1;
211
212			extcon_set_state_sync(usbsw->edev, cable, attached);
213			cables &= ~BIT_ULL(cable);
214		}
215
216		mask &= ~BIT_ULL(dev);
217	}
218}
219
220static void fsa9480_detect_dev(struct fsa9480_usbsw *usbsw)
221{
222	int val1, val2;
223	u16 val;
224
225	val1 = fsa9480_read_reg(usbsw, FSA9480_REG_DEV_T1);
226	val2 = fsa9480_read_reg(usbsw, FSA9480_REG_DEV_T2);
227	if (val1 < 0 || val2 < 0) {
228		dev_err(usbsw->dev, "%s: failed to read registers", __func__);
229		return;
230	}
231	val = val2 << 8 | val1;
232
233	dev_info(usbsw->dev, "dev1: 0x%x, dev2: 0x%x\n", val1, val2);
234
235	/* handle detached cables first */
236	fsa9480_handle_change(usbsw, usbsw->cable & ~val, false);
237
238	/* then handle attached ones */
239	fsa9480_handle_change(usbsw, val & ~usbsw->cable, true);
240
241	usbsw->cable = val;
242}
243
244static irqreturn_t fsa9480_irq_handler(int irq, void *data)
245{
246	struct fsa9480_usbsw *usbsw = data;
247	int intr = 0;
248
249	/* clear interrupt */
250	fsa9480_read_irq(usbsw, &intr);
251	if (!intr)
252		return IRQ_NONE;
253
254	/* device detection */
255	fsa9480_detect_dev(usbsw);
256
257	return IRQ_HANDLED;
258}
259
260static int fsa9480_probe(struct i2c_client *client)
261{
262	struct fsa9480_usbsw *info;
263	int ret;
264
265	if (!client->irq) {
266		dev_err(&client->dev, "no interrupt provided\n");
267		return -EINVAL;
268	}
269
270	info = devm_kzalloc(&client->dev, sizeof(*info), GFP_KERNEL);
271	if (!info)
272		return -ENOMEM;
273	info->dev = &client->dev;
274
275	i2c_set_clientdata(client, info);
276
277	/* External connector */
278	info->edev = devm_extcon_dev_allocate(info->dev,
279					      fsa9480_extcon_cable);
280	if (IS_ERR(info->edev)) {
281		dev_err(info->dev, "failed to allocate memory for extcon\n");
282		ret = -ENOMEM;
283		return ret;
284	}
285
286	ret = devm_extcon_dev_register(info->dev, info->edev);
287	if (ret) {
288		dev_err(info->dev, "failed to register extcon device\n");
289		return ret;
290	}
291
292	info->regmap = devm_regmap_init_i2c(client, &fsa9480_regmap_config);
293	if (IS_ERR(info->regmap)) {
294		ret = PTR_ERR(info->regmap);
295		dev_err(info->dev, "failed to allocate register map: %d\n",
296			ret);
297		return ret;
298	}
299
300	/* ADC Detect Time: 500ms */
301	fsa9480_write_reg(info, FSA9480_REG_TIMING1, TIMING1_ADC_500MS);
302
303	/* configure automatic switching */
304	fsa9480_write_reg(info, FSA9480_REG_CTRL, CON_MASK);
305
306	/* unmask interrupt (attach/detach only) */
307	fsa9480_write_reg(info, FSA9480_REG_INT1_MASK,
308			  INT1_MASK & ~(INT_ATTACH | INT_DETACH));
309	fsa9480_write_reg(info, FSA9480_REG_INT2_MASK, INT2_MASK);
310
311	ret = devm_request_threaded_irq(info->dev, client->irq, NULL,
312					fsa9480_irq_handler,
313					IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
314					"fsa9480", info);
315	if (ret) {
316		dev_err(info->dev, "failed to request IRQ\n");
317		return ret;
318	}
319
320	device_init_wakeup(info->dev, true);
321	fsa9480_detect_dev(info);
322
323	return 0;
324}
325
326#ifdef CONFIG_PM_SLEEP
327static int fsa9480_suspend(struct device *dev)
328{
329	struct i2c_client *client = to_i2c_client(dev);
330
331	if (device_may_wakeup(&client->dev) && client->irq)
332		enable_irq_wake(client->irq);
333
334	return 0;
335}
336
337static int fsa9480_resume(struct device *dev)
338{
339	struct i2c_client *client = to_i2c_client(dev);
340
341	if (device_may_wakeup(&client->dev) && client->irq)
342		disable_irq_wake(client->irq);
343
344	return 0;
345}
346#endif
347
348static const struct dev_pm_ops fsa9480_pm_ops = {
349	SET_SYSTEM_SLEEP_PM_OPS(fsa9480_suspend, fsa9480_resume)
350};
351
352static const struct i2c_device_id fsa9480_id[] = {
353	{ "fsa9480", 0 },
354	{}
355};
356MODULE_DEVICE_TABLE(i2c, fsa9480_id);
357
358static const struct of_device_id fsa9480_of_match[] = {
359	{ .compatible = "fcs,fsa9480", },
360	{ .compatible = "fcs,fsa880", },
361	{ .compatible = "ti,tsu6111", },
362	{ },
363};
364MODULE_DEVICE_TABLE(of, fsa9480_of_match);
365
366static struct i2c_driver fsa9480_i2c_driver = {
367	.driver			= {
368		.name		= "fsa9480",
369		.pm		= &fsa9480_pm_ops,
370		.of_match_table = fsa9480_of_match,
371	},
372	.probe			= fsa9480_probe,
373	.id_table		= fsa9480_id,
374};
375
376static int __init fsa9480_module_init(void)
377{
378	return i2c_add_driver(&fsa9480_i2c_driver);
379}
380subsys_initcall(fsa9480_module_init);
381
382static void __exit fsa9480_module_exit(void)
383{
384	i2c_del_driver(&fsa9480_i2c_driver);
385}
386module_exit(fsa9480_module_exit);
387
388MODULE_DESCRIPTION("Fairchild Semiconductor FSA9480 extcon driver");
389MODULE_AUTHOR("Tomasz Figa <tomasz.figa@gmail.com>");
390MODULE_LICENSE("GPL");
391