xref: /openbmc/linux/drivers/mfd/twl6030-irq.c (revision 12eb4683)
1 /*
2  * twl6030-irq.c - TWL6030 irq support
3  *
4  * Copyright (C) 2005-2009 Texas Instruments, Inc.
5  *
6  * Modifications to defer interrupt handling to a kernel thread:
7  * Copyright (C) 2006 MontaVista Software, Inc.
8  *
9  * Based on tlv320aic23.c:
10  * Copyright (c) by Kai Svahn <kai.svahn@nokia.com>
11  *
12  * Code cleanup and modifications to IRQ handler.
13  * by syed khasim <x0khasim@ti.com>
14  *
15  * TWL6030 specific code and IRQ handling changes by
16  * Jagadeesh Bhaskar Pakaravoor <j-pakaravoor@ti.com>
17  * Balaji T K <balajitk@ti.com>
18  *
19  * This program is free software; you can redistribute it and/or modify
20  * it under the terms of the GNU General Public License as published by
21  * the Free Software Foundation; either version 2 of the License, or
22  * (at your option) any later version.
23  *
24  * This program is distributed in the hope that it will be useful,
25  * but WITHOUT ANY WARRANTY; without even the implied warranty of
26  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
27  * GNU General Public License for more details.
28  *
29  * You should have received a copy of the GNU General Public License
30  * along with this program; if not, write to the Free Software
31  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
32  */
33 
34 #include <linux/init.h>
35 #include <linux/export.h>
36 #include <linux/interrupt.h>
37 #include <linux/irq.h>
38 #include <linux/kthread.h>
39 #include <linux/i2c/twl.h>
40 #include <linux/platform_device.h>
41 #include <linux/suspend.h>
42 #include <linux/of.h>
43 #include <linux/irqdomain.h>
44 #include <linux/of_device.h>
45 
46 #include "twl-core.h"
47 
48 /*
49  * TWL6030 (unlike its predecessors, which had two level interrupt handling)
50  * three interrupt registers INT_STS_A, INT_STS_B and INT_STS_C.
51  * It exposes status bits saying who has raised an interrupt. There are
52  * three mask registers that corresponds to these status registers, that
53  * enables/disables these interrupts.
54  *
55  * We set up IRQs starting at a platform-specified base. An interrupt map table,
56  * specifies mapping between interrupt number and the associated module.
57  */
58 #define TWL6030_NR_IRQS    20
59 
60 static int twl6030_interrupt_mapping[24] = {
61 	PWR_INTR_OFFSET,	/* Bit 0	PWRON			*/
62 	PWR_INTR_OFFSET,	/* Bit 1	RPWRON			*/
63 	PWR_INTR_OFFSET,	/* Bit 2	BAT_VLOW		*/
64 	RTC_INTR_OFFSET,	/* Bit 3	RTC_ALARM		*/
65 	RTC_INTR_OFFSET,	/* Bit 4	RTC_PERIOD		*/
66 	HOTDIE_INTR_OFFSET,	/* Bit 5	HOT_DIE			*/
67 	SMPSLDO_INTR_OFFSET,	/* Bit 6	VXXX_SHORT		*/
68 	SMPSLDO_INTR_OFFSET,	/* Bit 7	VMMC_SHORT		*/
69 
70 	SMPSLDO_INTR_OFFSET,	/* Bit 8	VUSIM_SHORT		*/
71 	BATDETECT_INTR_OFFSET,	/* Bit 9	BAT			*/
72 	SIMDETECT_INTR_OFFSET,	/* Bit 10	SIM			*/
73 	MMCDETECT_INTR_OFFSET,	/* Bit 11	MMC			*/
74 	RSV_INTR_OFFSET,  	/* Bit 12	Reserved		*/
75 	MADC_INTR_OFFSET,	/* Bit 13	GPADC_RT_EOC		*/
76 	MADC_INTR_OFFSET,	/* Bit 14	GPADC_SW_EOC		*/
77 	GASGAUGE_INTR_OFFSET,	/* Bit 15	CC_AUTOCAL		*/
78 
79 	USBOTG_INTR_OFFSET,	/* Bit 16	ID_WKUP			*/
80 	USBOTG_INTR_OFFSET,	/* Bit 17	VBUS_WKUP		*/
81 	USBOTG_INTR_OFFSET,	/* Bit 18	ID			*/
82 	USB_PRES_INTR_OFFSET,	/* Bit 19	VBUS			*/
83 	CHARGER_INTR_OFFSET,	/* Bit 20	CHRG_CTRL		*/
84 	CHARGERFAULT_INTR_OFFSET,	/* Bit 21	EXT_CHRG	*/
85 	CHARGERFAULT_INTR_OFFSET,	/* Bit 22	INT_CHRG	*/
86 	RSV_INTR_OFFSET,	/* Bit 23	Reserved		*/
87 };
88 
89 static int twl6032_interrupt_mapping[24] = {
90 	PWR_INTR_OFFSET,	/* Bit 0	PWRON			*/
91 	PWR_INTR_OFFSET,	/* Bit 1	RPWRON			*/
92 	PWR_INTR_OFFSET,	/* Bit 2	SYS_VLOW		*/
93 	RTC_INTR_OFFSET,	/* Bit 3	RTC_ALARM		*/
94 	RTC_INTR_OFFSET,	/* Bit 4	RTC_PERIOD		*/
95 	HOTDIE_INTR_OFFSET,	/* Bit 5	HOT_DIE			*/
96 	SMPSLDO_INTR_OFFSET,	/* Bit 6	VXXX_SHORT		*/
97 	PWR_INTR_OFFSET,	/* Bit 7	SPDURATION		*/
98 
99 	PWR_INTR_OFFSET,	/* Bit 8	WATCHDOG		*/
100 	BATDETECT_INTR_OFFSET,	/* Bit 9	BAT			*/
101 	SIMDETECT_INTR_OFFSET,	/* Bit 10	SIM			*/
102 	MMCDETECT_INTR_OFFSET,	/* Bit 11	MMC			*/
103 	MADC_INTR_OFFSET,	/* Bit 12	GPADC_RT_EOC		*/
104 	MADC_INTR_OFFSET,	/* Bit 13	GPADC_SW_EOC		*/
105 	GASGAUGE_INTR_OFFSET,	/* Bit 14	CC_EOC			*/
106 	GASGAUGE_INTR_OFFSET,	/* Bit 15	CC_AUTOCAL		*/
107 
108 	USBOTG_INTR_OFFSET,	/* Bit 16	ID_WKUP			*/
109 	USBOTG_INTR_OFFSET,	/* Bit 17	VBUS_WKUP		*/
110 	USBOTG_INTR_OFFSET,	/* Bit 18	ID			*/
111 	USB_PRES_INTR_OFFSET,	/* Bit 19	VBUS			*/
112 	CHARGER_INTR_OFFSET,	/* Bit 20	CHRG_CTRL		*/
113 	CHARGERFAULT_INTR_OFFSET,	/* Bit 21	EXT_CHRG	*/
114 	CHARGERFAULT_INTR_OFFSET,	/* Bit 22	INT_CHRG	*/
115 	RSV_INTR_OFFSET,	/* Bit 23	Reserved		*/
116 };
117 
118 /*----------------------------------------------------------------------*/
119 
120 struct twl6030_irq {
121 	unsigned int		irq_base;
122 	int			twl_irq;
123 	bool			irq_wake_enabled;
124 	atomic_t		wakeirqs;
125 	struct notifier_block	pm_nb;
126 	struct irq_chip		irq_chip;
127 	struct irq_domain	*irq_domain;
128 	const int		*irq_mapping_tbl;
129 };
130 
131 static struct twl6030_irq *twl6030_irq;
132 
133 static int twl6030_irq_pm_notifier(struct notifier_block *notifier,
134 				   unsigned long pm_event, void *unused)
135 {
136 	int chained_wakeups;
137 	struct twl6030_irq *pdata = container_of(notifier, struct twl6030_irq,
138 						  pm_nb);
139 
140 	switch (pm_event) {
141 	case PM_SUSPEND_PREPARE:
142 		chained_wakeups = atomic_read(&pdata->wakeirqs);
143 
144 		if (chained_wakeups && !pdata->irq_wake_enabled) {
145 			if (enable_irq_wake(pdata->twl_irq))
146 				pr_err("twl6030 IRQ wake enable failed\n");
147 			else
148 				pdata->irq_wake_enabled = true;
149 		} else if (!chained_wakeups && pdata->irq_wake_enabled) {
150 			disable_irq_wake(pdata->twl_irq);
151 			pdata->irq_wake_enabled = false;
152 		}
153 
154 		disable_irq(pdata->twl_irq);
155 		break;
156 
157 	case PM_POST_SUSPEND:
158 		enable_irq(pdata->twl_irq);
159 		break;
160 
161 	default:
162 		break;
163 	}
164 
165 	return NOTIFY_DONE;
166 }
167 
168 /*
169 * Threaded irq handler for the twl6030 interrupt.
170 * We query the interrupt controller in the twl6030 to determine
171 * which module is generating the interrupt request and call
172 * handle_nested_irq for that module.
173 */
174 static irqreturn_t twl6030_irq_thread(int irq, void *data)
175 {
176 	int i, ret;
177 	union {
178 		u8 bytes[4];
179 		u32 int_sts;
180 	} sts;
181 	struct twl6030_irq *pdata = data;
182 
183 	/* read INT_STS_A, B and C in one shot using a burst read */
184 	ret = twl_i2c_read(TWL_MODULE_PIH, sts.bytes, REG_INT_STS_A, 3);
185 	if (ret) {
186 		pr_warn("twl6030_irq: I2C error %d reading PIH ISR\n", ret);
187 		return IRQ_HANDLED;
188 	}
189 
190 	sts.bytes[3] = 0; /* Only 24 bits are valid*/
191 
192 	/*
193 	 * Since VBUS status bit is not reliable for VBUS disconnect
194 	 * use CHARGER VBUS detection status bit instead.
195 	 */
196 	if (sts.bytes[2] & 0x10)
197 		sts.bytes[2] |= 0x08;
198 
199 	for (i = 0; sts.int_sts; sts.int_sts >>= 1, i++)
200 		if (sts.int_sts & 0x1) {
201 			int module_irq =
202 				irq_find_mapping(pdata->irq_domain,
203 						 pdata->irq_mapping_tbl[i]);
204 			if (module_irq)
205 				handle_nested_irq(module_irq);
206 			else
207 				pr_err("twl6030_irq: Unmapped PIH ISR %u detected\n",
208 				       i);
209 			pr_debug("twl6030_irq: PIH ISR %u, virq%u\n",
210 				 i, module_irq);
211 		}
212 
213 	/*
214 	 * NOTE:
215 	 * Simulation confirms that documentation is wrong w.r.t the
216 	 * interrupt status clear operation. A single *byte* write to
217 	 * any one of STS_A to STS_C register results in all three
218 	 * STS registers being reset. Since it does not matter which
219 	 * value is written, all three registers are cleared on a
220 	 * single byte write, so we just use 0x0 to clear.
221 	 */
222 	ret = twl_i2c_write_u8(TWL_MODULE_PIH, 0x00, REG_INT_STS_A);
223 	if (ret)
224 		pr_warn("twl6030_irq: I2C error in clearing PIH ISR\n");
225 
226 	return IRQ_HANDLED;
227 }
228 
229 /*----------------------------------------------------------------------*/
230 
231 static int twl6030_irq_set_wake(struct irq_data *d, unsigned int on)
232 {
233 	struct twl6030_irq *pdata = irq_get_chip_data(d->irq);
234 
235 	if (on)
236 		atomic_inc(&pdata->wakeirqs);
237 	else
238 		atomic_dec(&pdata->wakeirqs);
239 
240 	return 0;
241 }
242 
243 int twl6030_interrupt_unmask(u8 bit_mask, u8 offset)
244 {
245 	int ret;
246 	u8 unmask_value;
247 	ret = twl_i2c_read_u8(TWL_MODULE_PIH, &unmask_value,
248 			REG_INT_STS_A + offset);
249 	unmask_value &= (~(bit_mask));
250 	ret |= twl_i2c_write_u8(TWL_MODULE_PIH, unmask_value,
251 			REG_INT_STS_A + offset); /* unmask INT_MSK_A/B/C */
252 	return ret;
253 }
254 EXPORT_SYMBOL(twl6030_interrupt_unmask);
255 
256 int twl6030_interrupt_mask(u8 bit_mask, u8 offset)
257 {
258 	int ret;
259 	u8 mask_value;
260 	ret = twl_i2c_read_u8(TWL_MODULE_PIH, &mask_value,
261 			REG_INT_STS_A + offset);
262 	mask_value |= (bit_mask);
263 	ret |= twl_i2c_write_u8(TWL_MODULE_PIH, mask_value,
264 			REG_INT_STS_A + offset); /* mask INT_MSK_A/B/C */
265 	return ret;
266 }
267 EXPORT_SYMBOL(twl6030_interrupt_mask);
268 
269 int twl6030_mmc_card_detect_config(void)
270 {
271 	int ret;
272 	u8 reg_val = 0;
273 
274 	/* Unmasking the Card detect Interrupt line for MMC1 from Phoenix */
275 	twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
276 						REG_INT_MSK_LINE_B);
277 	twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
278 						REG_INT_MSK_STS_B);
279 	/*
280 	 * Initially Configuring MMC_CTRL for receiving interrupts &
281 	 * Card status on TWL6030 for MMC1
282 	 */
283 	ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &reg_val, TWL6030_MMCCTRL);
284 	if (ret < 0) {
285 		pr_err("twl6030: Failed to read MMCCTRL, error %d\n", ret);
286 		return ret;
287 	}
288 	reg_val &= ~VMMC_AUTO_OFF;
289 	reg_val |= SW_FC;
290 	ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val, TWL6030_MMCCTRL);
291 	if (ret < 0) {
292 		pr_err("twl6030: Failed to write MMCCTRL, error %d\n", ret);
293 		return ret;
294 	}
295 
296 	/* Configuring PullUp-PullDown register */
297 	ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &reg_val,
298 						TWL6030_CFG_INPUT_PUPD3);
299 	if (ret < 0) {
300 		pr_err("twl6030: Failed to read CFG_INPUT_PUPD3, error %d\n",
301 									ret);
302 		return ret;
303 	}
304 	reg_val &= ~(MMC_PU | MMC_PD);
305 	ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val,
306 						TWL6030_CFG_INPUT_PUPD3);
307 	if (ret < 0) {
308 		pr_err("twl6030: Failed to write CFG_INPUT_PUPD3, error %d\n",
309 									ret);
310 		return ret;
311 	}
312 
313 	return irq_find_mapping(twl6030_irq->irq_domain,
314 				 MMCDETECT_INTR_OFFSET);
315 }
316 EXPORT_SYMBOL(twl6030_mmc_card_detect_config);
317 
318 int twl6030_mmc_card_detect(struct device *dev, int slot)
319 {
320 	int ret = -EIO;
321 	u8 read_reg = 0;
322 	struct platform_device *pdev = to_platform_device(dev);
323 
324 	if (pdev->id) {
325 		/* TWL6030 provide's Card detect support for
326 		 * only MMC1 controller.
327 		 */
328 		pr_err("Unknown MMC controller %d in %s\n", pdev->id, __func__);
329 		return ret;
330 	}
331 	/*
332 	 * BIT0 of MMC_CTRL on TWL6030 provides card status for MMC1
333 	 * 0 - Card not present ,1 - Card present
334 	 */
335 	ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &read_reg,
336 						TWL6030_MMCCTRL);
337 	if (ret >= 0)
338 		ret = read_reg & STS_MMC;
339 	return ret;
340 }
341 EXPORT_SYMBOL(twl6030_mmc_card_detect);
342 
343 static int twl6030_irq_map(struct irq_domain *d, unsigned int virq,
344 			      irq_hw_number_t hwirq)
345 {
346 	struct twl6030_irq *pdata = d->host_data;
347 
348 	irq_set_chip_data(virq, pdata);
349 	irq_set_chip_and_handler(virq,  &pdata->irq_chip, handle_simple_irq);
350 	irq_set_nested_thread(virq, true);
351 	irq_set_parent(virq, pdata->twl_irq);
352 
353 #ifdef CONFIG_ARM
354 	/*
355 	 * ARM requires an extra step to clear IRQ_NOREQUEST, which it
356 	 * sets on behalf of every irq_chip.  Also sets IRQ_NOPROBE.
357 	 */
358 	set_irq_flags(virq, IRQF_VALID);
359 #else
360 	/* same effect on other architectures */
361 	irq_set_noprobe(virq);
362 #endif
363 
364 	return 0;
365 }
366 
367 static void twl6030_irq_unmap(struct irq_domain *d, unsigned int virq)
368 {
369 #ifdef CONFIG_ARM
370 	set_irq_flags(virq, 0);
371 #endif
372 	irq_set_chip_and_handler(virq, NULL, NULL);
373 	irq_set_chip_data(virq, NULL);
374 }
375 
376 static struct irq_domain_ops twl6030_irq_domain_ops = {
377 	.map	= twl6030_irq_map,
378 	.unmap	= twl6030_irq_unmap,
379 	.xlate	= irq_domain_xlate_onetwocell,
380 };
381 
382 static const struct of_device_id twl6030_of_match[] = {
383 	{.compatible = "ti,twl6030", &twl6030_interrupt_mapping},
384 	{.compatible = "ti,twl6032", &twl6032_interrupt_mapping},
385 	{ },
386 };
387 
388 int twl6030_init_irq(struct device *dev, int irq_num)
389 {
390 	struct			device_node *node = dev->of_node;
391 	int			nr_irqs;
392 	int			status;
393 	u8			mask[3];
394 	const struct of_device_id *of_id;
395 
396 	of_id = of_match_device(twl6030_of_match, dev);
397 	if (!of_id || !of_id->data) {
398 		dev_err(dev, "Unknown TWL device model\n");
399 		return -EINVAL;
400 	}
401 
402 	nr_irqs = TWL6030_NR_IRQS;
403 
404 	twl6030_irq = devm_kzalloc(dev, sizeof(*twl6030_irq), GFP_KERNEL);
405 	if (!twl6030_irq) {
406 		dev_err(dev, "twl6030_irq: Memory allocation failed\n");
407 		return -ENOMEM;
408 	}
409 
410 	mask[0] = 0xFF;
411 	mask[1] = 0xFF;
412 	mask[2] = 0xFF;
413 
414 	/* mask all int lines */
415 	status = twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_MSK_LINE_A, 3);
416 	/* mask all int sts */
417 	status |= twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_MSK_STS_A, 3);
418 	/* clear INT_STS_A,B,C */
419 	status |= twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_STS_A, 3);
420 
421 	if (status < 0) {
422 		dev_err(dev, "I2C err writing TWL_MODULE_PIH: %d\n", status);
423 		return status;
424 	}
425 
426 	/*
427 	 * install an irq handler for each of the modules;
428 	 * clone dummy irq_chip since PIH can't *do* anything
429 	 */
430 	twl6030_irq->irq_chip = dummy_irq_chip;
431 	twl6030_irq->irq_chip.name = "twl6030";
432 	twl6030_irq->irq_chip.irq_set_type = NULL;
433 	twl6030_irq->irq_chip.irq_set_wake = twl6030_irq_set_wake;
434 
435 	twl6030_irq->pm_nb.notifier_call = twl6030_irq_pm_notifier;
436 	atomic_set(&twl6030_irq->wakeirqs, 0);
437 	twl6030_irq->irq_mapping_tbl = of_id->data;
438 
439 	twl6030_irq->irq_domain =
440 		irq_domain_add_linear(node, nr_irqs,
441 				      &twl6030_irq_domain_ops, twl6030_irq);
442 	if (!twl6030_irq->irq_domain) {
443 		dev_err(dev, "Can't add irq_domain\n");
444 		return -ENOMEM;
445 	}
446 
447 	dev_info(dev, "PIH (irq %d) nested IRQs\n", irq_num);
448 
449 	/* install an irq handler to demultiplex the TWL6030 interrupt */
450 	status = request_threaded_irq(irq_num, NULL, twl6030_irq_thread,
451 				      IRQF_ONESHOT, "TWL6030-PIH", twl6030_irq);
452 	if (status < 0) {
453 		dev_err(dev, "could not claim irq %d: %d\n", irq_num, status);
454 		goto fail_irq;
455 	}
456 
457 	twl6030_irq->twl_irq = irq_num;
458 	register_pm_notifier(&twl6030_irq->pm_nb);
459 	return 0;
460 
461 fail_irq:
462 	irq_domain_remove(twl6030_irq->irq_domain);
463 	return status;
464 }
465 
466 int twl6030_exit_irq(void)
467 {
468 	if (twl6030_irq && twl6030_irq->twl_irq) {
469 		unregister_pm_notifier(&twl6030_irq->pm_nb);
470 		free_irq(twl6030_irq->twl_irq, NULL);
471 		/*
472 		 * TODO: IRQ domain and allocated nested IRQ descriptors
473 		 * should be freed somehow here. Now It can't be done, because
474 		 * child devices will not be deleted during removing of
475 		 * TWL Core driver and they will still contain allocated
476 		 * virt IRQs in their Resources tables.
477 		 * The same prevents us from using devm_request_threaded_irq()
478 		 * in this module.
479 		 */
480 	}
481 	return 0;
482 }
483 
484