xref: /openbmc/linux/drivers/mfd/pcf50633-irq.c (revision 21ab7031)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* NXP PCF50633 Power Management Unit (PMU) driver
3  *
4  * (C) 2006-2008 by Openmoko, Inc.
5  * Author: Harald Welte <laforge@openmoko.org>
6  * 	   Balaji Rao <balajirrao@openmoko.org>
7  * All rights reserved.
8  */
9 
10 #include <linux/i2c.h>
11 #include <linux/interrupt.h>
12 #include <linux/kernel.h>
13 #include <linux/mutex.h>
14 #include <linux/export.h>
15 #include <linux/slab.h>
16 
17 #include <linux/mfd/pcf50633/core.h>
18 #include <linux/mfd/pcf50633/mbc.h>
19 
20 int pcf50633_register_irq(struct pcf50633 *pcf, int irq,
21 			void (*handler) (int, void *), void *data)
22 {
23 	if (irq < 0 || irq >= PCF50633_NUM_IRQ || !handler)
24 		return -EINVAL;
25 
26 	if (WARN_ON(pcf->irq_handler[irq].handler))
27 		return -EBUSY;
28 
29 	mutex_lock(&pcf->lock);
30 	pcf->irq_handler[irq].handler = handler;
31 	pcf->irq_handler[irq].data = data;
32 	mutex_unlock(&pcf->lock);
33 
34 	return 0;
35 }
36 EXPORT_SYMBOL_GPL(pcf50633_register_irq);
37 
38 int pcf50633_free_irq(struct pcf50633 *pcf, int irq)
39 {
40 	if (irq < 0 || irq >= PCF50633_NUM_IRQ)
41 		return -EINVAL;
42 
43 	mutex_lock(&pcf->lock);
44 	pcf->irq_handler[irq].handler = NULL;
45 	mutex_unlock(&pcf->lock);
46 
47 	return 0;
48 }
49 EXPORT_SYMBOL_GPL(pcf50633_free_irq);
50 
51 static int __pcf50633_irq_mask_set(struct pcf50633 *pcf, int irq, u8 mask)
52 {
53 	u8 reg, bit;
54 	int idx;
55 
56 	idx = irq >> 3;
57 	reg = PCF50633_REG_INT1M + idx;
58 	bit = 1 << (irq & 0x07);
59 
60 	pcf50633_reg_set_bit_mask(pcf, reg, bit, mask ? bit : 0);
61 
62 	mutex_lock(&pcf->lock);
63 
64 	if (mask)
65 		pcf->mask_regs[idx] |= bit;
66 	else
67 		pcf->mask_regs[idx] &= ~bit;
68 
69 	mutex_unlock(&pcf->lock);
70 
71 	return 0;
72 }
73 
74 int pcf50633_irq_mask(struct pcf50633 *pcf, int irq)
75 {
76 	dev_dbg(pcf->dev, "Masking IRQ %d\n", irq);
77 
78 	return __pcf50633_irq_mask_set(pcf, irq, 1);
79 }
80 EXPORT_SYMBOL_GPL(pcf50633_irq_mask);
81 
82 int pcf50633_irq_unmask(struct pcf50633 *pcf, int irq)
83 {
84 	dev_dbg(pcf->dev, "Unmasking IRQ %d\n", irq);
85 
86 	return __pcf50633_irq_mask_set(pcf, irq, 0);
87 }
88 EXPORT_SYMBOL_GPL(pcf50633_irq_unmask);
89 
90 int pcf50633_irq_mask_get(struct pcf50633 *pcf, int irq)
91 {
92 	u8 reg, bits;
93 
94 	reg =  irq >> 3;
95 	bits = 1 << (irq & 0x07);
96 
97 	return pcf->mask_regs[reg] & bits;
98 }
99 EXPORT_SYMBOL_GPL(pcf50633_irq_mask_get);
100 
101 static void pcf50633_irq_call_handler(struct pcf50633 *pcf, int irq)
102 {
103 	if (pcf->irq_handler[irq].handler)
104 		pcf->irq_handler[irq].handler(irq, pcf->irq_handler[irq].data);
105 }
106 
107 /* Maximum amount of time ONKEY is held before emergency action is taken */
108 #define PCF50633_ONKEY1S_TIMEOUT 8
109 
110 static irqreturn_t pcf50633_irq(int irq, void *data)
111 {
112 	struct pcf50633 *pcf = data;
113 	int ret, i, j;
114 	u8 pcf_int[5], chgstat;
115 
116 	/* Read the 5 INT regs in one transaction */
117 	ret = pcf50633_read_block(pcf, PCF50633_REG_INT1,
118 						ARRAY_SIZE(pcf_int), pcf_int);
119 	if (ret != ARRAY_SIZE(pcf_int)) {
120 		dev_err(pcf->dev, "Error reading INT registers\n");
121 
122 		/*
123 		 * If this doesn't ACK the interrupt to the chip, we'll be
124 		 * called once again as we're level triggered.
125 		 */
126 		goto out;
127 	}
128 
129 	/* defeat 8s death from lowsys on A5 */
130 	pcf50633_reg_write(pcf, PCF50633_REG_OOCSHDWN,  0x04);
131 
132 	/* We immediately read the usb and adapter status. We thus make sure
133 	 * only of USBINS/USBREM IRQ handlers are called */
134 	if (pcf_int[0] & (PCF50633_INT1_USBINS | PCF50633_INT1_USBREM)) {
135 		chgstat = pcf50633_reg_read(pcf, PCF50633_REG_MBCS2);
136 		if (chgstat & (0x3 << 4))
137 			pcf_int[0] &= ~PCF50633_INT1_USBREM;
138 		else
139 			pcf_int[0] &= ~PCF50633_INT1_USBINS;
140 	}
141 
142 	/* Make sure only one of ADPINS or ADPREM is set */
143 	if (pcf_int[0] & (PCF50633_INT1_ADPINS | PCF50633_INT1_ADPREM)) {
144 		chgstat = pcf50633_reg_read(pcf, PCF50633_REG_MBCS2);
145 		if (chgstat & (0x3 << 4))
146 			pcf_int[0] &= ~PCF50633_INT1_ADPREM;
147 		else
148 			pcf_int[0] &= ~PCF50633_INT1_ADPINS;
149 	}
150 
151 	dev_dbg(pcf->dev, "INT1=0x%02x INT2=0x%02x INT3=0x%02x "
152 			"INT4=0x%02x INT5=0x%02x\n", pcf_int[0],
153 			pcf_int[1], pcf_int[2], pcf_int[3], pcf_int[4]);
154 
155 	/* Some revisions of the chip don't have a 8s standby mode on
156 	 * ONKEY1S press. We try to manually do it in such cases. */
157 	if ((pcf_int[0] & PCF50633_INT1_SECOND) && pcf->onkey1s_held) {
158 		dev_info(pcf->dev, "ONKEY1S held for %d secs\n",
159 							pcf->onkey1s_held);
160 		if (pcf->onkey1s_held++ == PCF50633_ONKEY1S_TIMEOUT)
161 			if (pcf->pdata->force_shutdown)
162 				pcf->pdata->force_shutdown(pcf);
163 	}
164 
165 	if (pcf_int[2] & PCF50633_INT3_ONKEY1S) {
166 		dev_info(pcf->dev, "ONKEY1S held\n");
167 		pcf->onkey1s_held = 1 ;
168 
169 		/* Unmask IRQ_SECOND */
170 		pcf50633_reg_clear_bits(pcf, PCF50633_REG_INT1M,
171 						PCF50633_INT1_SECOND);
172 
173 		/* Unmask IRQ_ONKEYR */
174 		pcf50633_reg_clear_bits(pcf, PCF50633_REG_INT2M,
175 						PCF50633_INT2_ONKEYR);
176 	}
177 
178 	if ((pcf_int[1] & PCF50633_INT2_ONKEYR) && pcf->onkey1s_held) {
179 		pcf->onkey1s_held = 0;
180 
181 		/* Mask SECOND and ONKEYR interrupts */
182 		if (pcf->mask_regs[0] & PCF50633_INT1_SECOND)
183 			pcf50633_reg_set_bit_mask(pcf,
184 					PCF50633_REG_INT1M,
185 					PCF50633_INT1_SECOND,
186 					PCF50633_INT1_SECOND);
187 
188 		if (pcf->mask_regs[1] & PCF50633_INT2_ONKEYR)
189 			pcf50633_reg_set_bit_mask(pcf,
190 					PCF50633_REG_INT2M,
191 					PCF50633_INT2_ONKEYR,
192 					PCF50633_INT2_ONKEYR);
193 	}
194 
195 	/* Have we just resumed ? */
196 	if (pcf->is_suspended) {
197 		pcf->is_suspended = 0;
198 
199 		/* Set the resume reason filtering out non resumers */
200 		for (i = 0; i < ARRAY_SIZE(pcf_int); i++)
201 			pcf->resume_reason[i] = pcf_int[i] &
202 						pcf->pdata->resumers[i];
203 
204 		/* Make sure we don't pass on any ONKEY events to
205 		 * userspace now */
206 		pcf_int[1] &= ~(PCF50633_INT2_ONKEYR | PCF50633_INT2_ONKEYF);
207 	}
208 
209 	for (i = 0; i < ARRAY_SIZE(pcf_int); i++) {
210 		/* Unset masked interrupts */
211 		pcf_int[i] &= ~pcf->mask_regs[i];
212 
213 		for (j = 0; j < 8 ; j++)
214 			if (pcf_int[i] & (1 << j))
215 				pcf50633_irq_call_handler(pcf, (i * 8) + j);
216 	}
217 
218 out:
219 	return IRQ_HANDLED;
220 }
221 
222 static int pcf50633_suspend(struct device *dev)
223 {
224 	struct i2c_client *client = to_i2c_client(dev);
225 	struct pcf50633 *pcf = i2c_get_clientdata(client);
226 	int ret;
227 	int i;
228 	u8 res[5];
229 
230 
231 	/* Make sure our interrupt handlers are not called
232 	 * henceforth */
233 	disable_irq(pcf->irq);
234 
235 	/* Save the masks */
236 	ret = pcf50633_read_block(pcf, PCF50633_REG_INT1M,
237 				ARRAY_SIZE(pcf->suspend_irq_masks),
238 					pcf->suspend_irq_masks);
239 	if (ret < 0) {
240 		dev_err(pcf->dev, "error saving irq masks\n");
241 		goto out;
242 	}
243 
244 	/* Write wakeup irq masks */
245 	for (i = 0; i < ARRAY_SIZE(res); i++)
246 		res[i] = ~pcf->pdata->resumers[i];
247 
248 	ret = pcf50633_write_block(pcf, PCF50633_REG_INT1M,
249 					ARRAY_SIZE(res), &res[0]);
250 	if (ret < 0) {
251 		dev_err(pcf->dev, "error writing wakeup irq masks\n");
252 		goto out;
253 	}
254 
255 	pcf->is_suspended = 1;
256 
257 out:
258 	return ret;
259 }
260 
261 static int pcf50633_resume(struct device *dev)
262 {
263 	struct i2c_client *client = to_i2c_client(dev);
264 	struct pcf50633 *pcf = i2c_get_clientdata(client);
265 	int ret;
266 
267 	/* Write the saved mask registers */
268 	ret = pcf50633_write_block(pcf, PCF50633_REG_INT1M,
269 				ARRAY_SIZE(pcf->suspend_irq_masks),
270 					pcf->suspend_irq_masks);
271 	if (ret < 0)
272 		dev_err(pcf->dev, "Error restoring saved suspend masks\n");
273 
274 	enable_irq(pcf->irq);
275 
276 	return ret;
277 }
278 
279 EXPORT_GPL_SIMPLE_DEV_PM_OPS(pcf50633_pm, pcf50633_suspend, pcf50633_resume);
280 
281 int pcf50633_irq_init(struct pcf50633 *pcf, int irq)
282 {
283 	int ret;
284 
285 	pcf->irq = irq;
286 
287 	/* Enable all interrupts except RTC SECOND */
288 	pcf->mask_regs[0] = 0x80;
289 	pcf50633_reg_write(pcf, PCF50633_REG_INT1M, pcf->mask_regs[0]);
290 	pcf50633_reg_write(pcf, PCF50633_REG_INT2M, 0x00);
291 	pcf50633_reg_write(pcf, PCF50633_REG_INT3M, 0x00);
292 	pcf50633_reg_write(pcf, PCF50633_REG_INT4M, 0x00);
293 	pcf50633_reg_write(pcf, PCF50633_REG_INT5M, 0x00);
294 
295 	ret = request_threaded_irq(irq, NULL, pcf50633_irq,
296 					IRQF_TRIGGER_LOW | IRQF_ONESHOT,
297 					"pcf50633", pcf);
298 
299 	if (ret)
300 		dev_err(pcf->dev, "Failed to request IRQ %d\n", ret);
301 
302 	if (enable_irq_wake(irq) < 0)
303 		dev_err(pcf->dev, "IRQ %u cannot be enabled as wake-up source"
304 			"in this hardware revision", irq);
305 
306 	return ret;
307 }
308 
309 void pcf50633_irq_free(struct pcf50633 *pcf)
310 {
311 	free_irq(pcf->irq, pcf);
312 }
313