xref: /openbmc/linux/drivers/mfd/twl6030-irq.c (revision 94cdda6b)
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/export.h>
35 #include <linux/interrupt.h>
36 #include <linux/irq.h>
37 #include <linux/kthread.h>
38 #include <linux/i2c/twl.h>
39 #include <linux/platform_device.h>
40 #include <linux/suspend.h>
41 #include <linux/of.h>
42 #include <linux/irqdomain.h>
43 #include <linux/of_device.h>
44 
45 #include "twl-core.h"
46 
47 /*
48  * TWL6030 (unlike its predecessors, which had two level interrupt handling)
49  * three interrupt registers INT_STS_A, INT_STS_B and INT_STS_C.
50  * It exposes status bits saying who has raised an interrupt. There are
51  * three mask registers that corresponds to these status registers, that
52  * enables/disables these interrupts.
53  *
54  * We set up IRQs starting at a platform-specified base. An interrupt map table,
55  * specifies mapping between interrupt number and the associated module.
56  */
57 #define TWL6030_NR_IRQS    20
58 
59 static int twl6030_interrupt_mapping[24] = {
60 	PWR_INTR_OFFSET,	/* Bit 0	PWRON			*/
61 	PWR_INTR_OFFSET,	/* Bit 1	RPWRON			*/
62 	PWR_INTR_OFFSET,	/* Bit 2	BAT_VLOW		*/
63 	RTC_INTR_OFFSET,	/* Bit 3	RTC_ALARM		*/
64 	RTC_INTR_OFFSET,	/* Bit 4	RTC_PERIOD		*/
65 	HOTDIE_INTR_OFFSET,	/* Bit 5	HOT_DIE			*/
66 	SMPSLDO_INTR_OFFSET,	/* Bit 6	VXXX_SHORT		*/
67 	SMPSLDO_INTR_OFFSET,	/* Bit 7	VMMC_SHORT		*/
68 
69 	SMPSLDO_INTR_OFFSET,	/* Bit 8	VUSIM_SHORT		*/
70 	BATDETECT_INTR_OFFSET,	/* Bit 9	BAT			*/
71 	SIMDETECT_INTR_OFFSET,	/* Bit 10	SIM			*/
72 	MMCDETECT_INTR_OFFSET,	/* Bit 11	MMC			*/
73 	RSV_INTR_OFFSET,	/* Bit 12	Reserved		*/
74 	MADC_INTR_OFFSET,	/* Bit 13	GPADC_RT_EOC		*/
75 	MADC_INTR_OFFSET,	/* Bit 14	GPADC_SW_EOC		*/
76 	GASGAUGE_INTR_OFFSET,	/* Bit 15	CC_AUTOCAL		*/
77 
78 	USBOTG_INTR_OFFSET,	/* Bit 16	ID_WKUP			*/
79 	USBOTG_INTR_OFFSET,	/* Bit 17	VBUS_WKUP		*/
80 	USBOTG_INTR_OFFSET,	/* Bit 18	ID			*/
81 	USB_PRES_INTR_OFFSET,	/* Bit 19	VBUS			*/
82 	CHARGER_INTR_OFFSET,	/* Bit 20	CHRG_CTRL		*/
83 	CHARGERFAULT_INTR_OFFSET,	/* Bit 21	EXT_CHRG	*/
84 	CHARGERFAULT_INTR_OFFSET,	/* Bit 22	INT_CHRG	*/
85 	RSV_INTR_OFFSET,	/* Bit 23	Reserved		*/
86 };
87 
88 static int twl6032_interrupt_mapping[24] = {
89 	PWR_INTR_OFFSET,	/* Bit 0	PWRON			*/
90 	PWR_INTR_OFFSET,	/* Bit 1	RPWRON			*/
91 	PWR_INTR_OFFSET,	/* Bit 2	SYS_VLOW		*/
92 	RTC_INTR_OFFSET,	/* Bit 3	RTC_ALARM		*/
93 	RTC_INTR_OFFSET,	/* Bit 4	RTC_PERIOD		*/
94 	HOTDIE_INTR_OFFSET,	/* Bit 5	HOT_DIE			*/
95 	SMPSLDO_INTR_OFFSET,	/* Bit 6	VXXX_SHORT		*/
96 	PWR_INTR_OFFSET,	/* Bit 7	SPDURATION		*/
97 
98 	PWR_INTR_OFFSET,	/* Bit 8	WATCHDOG		*/
99 	BATDETECT_INTR_OFFSET,	/* Bit 9	BAT			*/
100 	SIMDETECT_INTR_OFFSET,	/* Bit 10	SIM			*/
101 	MMCDETECT_INTR_OFFSET,	/* Bit 11	MMC			*/
102 	MADC_INTR_OFFSET,	/* Bit 12	GPADC_RT_EOC		*/
103 	MADC_INTR_OFFSET,	/* Bit 13	GPADC_SW_EOC		*/
104 	GASGAUGE_INTR_OFFSET,	/* Bit 14	CC_EOC			*/
105 	GASGAUGE_INTR_OFFSET,	/* Bit 15	CC_AUTOCAL		*/
106 
107 	USBOTG_INTR_OFFSET,	/* Bit 16	ID_WKUP			*/
108 	USBOTG_INTR_OFFSET,	/* Bit 17	VBUS_WKUP		*/
109 	USBOTG_INTR_OFFSET,	/* Bit 18	ID			*/
110 	USB_PRES_INTR_OFFSET,	/* Bit 19	VBUS			*/
111 	CHARGER_INTR_OFFSET,	/* Bit 20	CHRG_CTRL		*/
112 	CHARGERFAULT_INTR_OFFSET,	/* Bit 21	EXT_CHRG	*/
113 	CHARGERFAULT_INTR_OFFSET,	/* Bit 22	INT_CHRG	*/
114 	RSV_INTR_OFFSET,	/* Bit 23	Reserved		*/
115 };
116 
117 /*----------------------------------------------------------------------*/
118 
119 struct twl6030_irq {
120 	unsigned int		irq_base;
121 	int			twl_irq;
122 	bool			irq_wake_enabled;
123 	atomic_t		wakeirqs;
124 	struct notifier_block	pm_nb;
125 	struct irq_chip		irq_chip;
126 	struct irq_domain	*irq_domain;
127 	const int		*irq_mapping_tbl;
128 };
129 
130 static struct twl6030_irq *twl6030_irq;
131 
132 static int twl6030_irq_pm_notifier(struct notifier_block *notifier,
133 				   unsigned long pm_event, void *unused)
134 {
135 	int chained_wakeups;
136 	struct twl6030_irq *pdata = container_of(notifier, struct twl6030_irq,
137 						  pm_nb);
138 
139 	switch (pm_event) {
140 	case PM_SUSPEND_PREPARE:
141 		chained_wakeups = atomic_read(&pdata->wakeirqs);
142 
143 		if (chained_wakeups && !pdata->irq_wake_enabled) {
144 			if (enable_irq_wake(pdata->twl_irq))
145 				pr_err("twl6030 IRQ wake enable failed\n");
146 			else
147 				pdata->irq_wake_enabled = true;
148 		} else if (!chained_wakeups && pdata->irq_wake_enabled) {
149 			disable_irq_wake(pdata->twl_irq);
150 			pdata->irq_wake_enabled = false;
151 		}
152 
153 		disable_irq(pdata->twl_irq);
154 		break;
155 
156 	case PM_POST_SUSPEND:
157 		enable_irq(pdata->twl_irq);
158 		break;
159 
160 	default:
161 		break;
162 	}
163 
164 	return NOTIFY_DONE;
165 }
166 
167 /*
168 * Threaded irq handler for the twl6030 interrupt.
169 * We query the interrupt controller in the twl6030 to determine
170 * which module is generating the interrupt request and call
171 * handle_nested_irq for that module.
172 */
173 static irqreturn_t twl6030_irq_thread(int irq, void *data)
174 {
175 	int i, ret;
176 	union {
177 		u8 bytes[4];
178 		__le32 int_sts;
179 	} sts;
180 	u32 int_sts; /* sts.int_sts converted to CPU endianness */
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 	int_sts = le32_to_cpu(sts.int_sts);
200 	for (i = 0; int_sts; int_sts >>= 1, i++)
201 		if (int_sts & 0x1) {
202 			int module_irq =
203 				irq_find_mapping(pdata->irq_domain,
204 						 pdata->irq_mapping_tbl[i]);
205 			if (module_irq)
206 				handle_nested_irq(module_irq);
207 			else
208 				pr_err("twl6030_irq: Unmapped PIH ISR %u detected\n",
209 				       i);
210 			pr_debug("twl6030_irq: PIH ISR %u, virq%u\n",
211 				 i, module_irq);
212 		}
213 
214 	/*
215 	 * NOTE:
216 	 * Simulation confirms that documentation is wrong w.r.t the
217 	 * interrupt status clear operation. A single *byte* write to
218 	 * any one of STS_A to STS_C register results in all three
219 	 * STS registers being reset. Since it does not matter which
220 	 * value is written, all three registers are cleared on a
221 	 * single byte write, so we just use 0x0 to clear.
222 	 */
223 	ret = twl_i2c_write_u8(TWL_MODULE_PIH, 0x00, REG_INT_STS_A);
224 	if (ret)
225 		pr_warn("twl6030_irq: I2C error in clearing PIH ISR\n");
226 
227 	return IRQ_HANDLED;
228 }
229 
230 /*----------------------------------------------------------------------*/
231 
232 static int twl6030_irq_set_wake(struct irq_data *d, unsigned int on)
233 {
234 	struct twl6030_irq *pdata = irq_get_chip_data(d->irq);
235 
236 	if (on)
237 		atomic_inc(&pdata->wakeirqs);
238 	else
239 		atomic_dec(&pdata->wakeirqs);
240 
241 	return 0;
242 }
243 
244 int twl6030_interrupt_unmask(u8 bit_mask, u8 offset)
245 {
246 	int ret;
247 	u8 unmask_value;
248 
249 	ret = twl_i2c_read_u8(TWL_MODULE_PIH, &unmask_value,
250 			REG_INT_STS_A + offset);
251 	unmask_value &= (~(bit_mask));
252 	ret |= twl_i2c_write_u8(TWL_MODULE_PIH, unmask_value,
253 			REG_INT_STS_A + offset); /* unmask INT_MSK_A/B/C */
254 	return ret;
255 }
256 EXPORT_SYMBOL(twl6030_interrupt_unmask);
257 
258 int twl6030_interrupt_mask(u8 bit_mask, u8 offset)
259 {
260 	int ret;
261 	u8 mask_value;
262 
263 	ret = twl_i2c_read_u8(TWL_MODULE_PIH, &mask_value,
264 			REG_INT_STS_A + offset);
265 	mask_value |= (bit_mask);
266 	ret |= twl_i2c_write_u8(TWL_MODULE_PIH, mask_value,
267 			REG_INT_STS_A + offset); /* mask INT_MSK_A/B/C */
268 	return ret;
269 }
270 EXPORT_SYMBOL(twl6030_interrupt_mask);
271 
272 int twl6030_mmc_card_detect_config(void)
273 {
274 	int ret;
275 	u8 reg_val = 0;
276 
277 	/* Unmasking the Card detect Interrupt line for MMC1 from Phoenix */
278 	twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
279 						REG_INT_MSK_LINE_B);
280 	twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
281 						REG_INT_MSK_STS_B);
282 	/*
283 	 * Initially Configuring MMC_CTRL for receiving interrupts &
284 	 * Card status on TWL6030 for MMC1
285 	 */
286 	ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &reg_val, TWL6030_MMCCTRL);
287 	if (ret < 0) {
288 		pr_err("twl6030: Failed to read MMCCTRL, error %d\n", ret);
289 		return ret;
290 	}
291 	reg_val &= ~VMMC_AUTO_OFF;
292 	reg_val |= SW_FC;
293 	ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val, TWL6030_MMCCTRL);
294 	if (ret < 0) {
295 		pr_err("twl6030: Failed to write MMCCTRL, error %d\n", ret);
296 		return ret;
297 	}
298 
299 	/* Configuring PullUp-PullDown register */
300 	ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &reg_val,
301 						TWL6030_CFG_INPUT_PUPD3);
302 	if (ret < 0) {
303 		pr_err("twl6030: Failed to read CFG_INPUT_PUPD3, error %d\n",
304 									ret);
305 		return ret;
306 	}
307 	reg_val &= ~(MMC_PU | MMC_PD);
308 	ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val,
309 						TWL6030_CFG_INPUT_PUPD3);
310 	if (ret < 0) {
311 		pr_err("twl6030: Failed to write CFG_INPUT_PUPD3, error %d\n",
312 									ret);
313 		return ret;
314 	}
315 
316 	return irq_find_mapping(twl6030_irq->irq_domain,
317 				 MMCDETECT_INTR_OFFSET);
318 }
319 EXPORT_SYMBOL(twl6030_mmc_card_detect_config);
320 
321 int twl6030_mmc_card_detect(struct device *dev, int slot)
322 {
323 	int ret = -EIO;
324 	u8 read_reg = 0;
325 	struct platform_device *pdev = to_platform_device(dev);
326 
327 	if (pdev->id) {
328 		/* TWL6030 provide's Card detect support for
329 		 * only MMC1 controller.
330 		 */
331 		pr_err("Unknown MMC controller %d in %s\n", pdev->id, __func__);
332 		return ret;
333 	}
334 	/*
335 	 * BIT0 of MMC_CTRL on TWL6030 provides card status for MMC1
336 	 * 0 - Card not present ,1 - Card present
337 	 */
338 	ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &read_reg,
339 						TWL6030_MMCCTRL);
340 	if (ret >= 0)
341 		ret = read_reg & STS_MMC;
342 	return ret;
343 }
344 EXPORT_SYMBOL(twl6030_mmc_card_detect);
345 
346 static int twl6030_irq_map(struct irq_domain *d, unsigned int virq,
347 			      irq_hw_number_t hwirq)
348 {
349 	struct twl6030_irq *pdata = d->host_data;
350 
351 	irq_set_chip_data(virq, pdata);
352 	irq_set_chip_and_handler(virq,  &pdata->irq_chip, handle_simple_irq);
353 	irq_set_nested_thread(virq, true);
354 	irq_set_parent(virq, pdata->twl_irq);
355 
356 #ifdef CONFIG_ARM
357 	/*
358 	 * ARM requires an extra step to clear IRQ_NOREQUEST, which it
359 	 * sets on behalf of every irq_chip.  Also sets IRQ_NOPROBE.
360 	 */
361 	set_irq_flags(virq, IRQF_VALID);
362 #else
363 	/* same effect on other architectures */
364 	irq_set_noprobe(virq);
365 #endif
366 
367 	return 0;
368 }
369 
370 static void twl6030_irq_unmap(struct irq_domain *d, unsigned int virq)
371 {
372 #ifdef CONFIG_ARM
373 	set_irq_flags(virq, 0);
374 #endif
375 	irq_set_chip_and_handler(virq, NULL, NULL);
376 	irq_set_chip_data(virq, NULL);
377 }
378 
379 static struct irq_domain_ops twl6030_irq_domain_ops = {
380 	.map	= twl6030_irq_map,
381 	.unmap	= twl6030_irq_unmap,
382 	.xlate	= irq_domain_xlate_onetwocell,
383 };
384 
385 static const struct of_device_id twl6030_of_match[] = {
386 	{.compatible = "ti,twl6030", &twl6030_interrupt_mapping},
387 	{.compatible = "ti,twl6032", &twl6032_interrupt_mapping},
388 	{ },
389 };
390 
391 int twl6030_init_irq(struct device *dev, int irq_num)
392 {
393 	struct			device_node *node = dev->of_node;
394 	int			nr_irqs;
395 	int			status;
396 	u8			mask[3];
397 	const struct of_device_id *of_id;
398 
399 	of_id = of_match_device(twl6030_of_match, dev);
400 	if (!of_id || !of_id->data) {
401 		dev_err(dev, "Unknown TWL device model\n");
402 		return -EINVAL;
403 	}
404 
405 	nr_irqs = TWL6030_NR_IRQS;
406 
407 	twl6030_irq = devm_kzalloc(dev, sizeof(*twl6030_irq), GFP_KERNEL);
408 	if (!twl6030_irq) {
409 		dev_err(dev, "twl6030_irq: Memory allocation failed\n");
410 		return -ENOMEM;
411 	}
412 
413 	mask[0] = 0xFF;
414 	mask[1] = 0xFF;
415 	mask[2] = 0xFF;
416 
417 	/* mask all int lines */
418 	status = twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_MSK_LINE_A, 3);
419 	/* mask all int sts */
420 	status |= twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_MSK_STS_A, 3);
421 	/* clear INT_STS_A,B,C */
422 	status |= twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_STS_A, 3);
423 
424 	if (status < 0) {
425 		dev_err(dev, "I2C err writing TWL_MODULE_PIH: %d\n", status);
426 		return status;
427 	}
428 
429 	/*
430 	 * install an irq handler for each of the modules;
431 	 * clone dummy irq_chip since PIH can't *do* anything
432 	 */
433 	twl6030_irq->irq_chip = dummy_irq_chip;
434 	twl6030_irq->irq_chip.name = "twl6030";
435 	twl6030_irq->irq_chip.irq_set_type = NULL;
436 	twl6030_irq->irq_chip.irq_set_wake = twl6030_irq_set_wake;
437 
438 	twl6030_irq->pm_nb.notifier_call = twl6030_irq_pm_notifier;
439 	atomic_set(&twl6030_irq->wakeirqs, 0);
440 	twl6030_irq->irq_mapping_tbl = of_id->data;
441 
442 	twl6030_irq->irq_domain =
443 		irq_domain_add_linear(node, nr_irqs,
444 				      &twl6030_irq_domain_ops, twl6030_irq);
445 	if (!twl6030_irq->irq_domain) {
446 		dev_err(dev, "Can't add irq_domain\n");
447 		return -ENOMEM;
448 	}
449 
450 	dev_info(dev, "PIH (irq %d) nested IRQs\n", irq_num);
451 
452 	/* install an irq handler to demultiplex the TWL6030 interrupt */
453 	status = request_threaded_irq(irq_num, NULL, twl6030_irq_thread,
454 				      IRQF_ONESHOT, "TWL6030-PIH", twl6030_irq);
455 	if (status < 0) {
456 		dev_err(dev, "could not claim irq %d: %d\n", irq_num, status);
457 		goto fail_irq;
458 	}
459 
460 	twl6030_irq->twl_irq = irq_num;
461 	register_pm_notifier(&twl6030_irq->pm_nb);
462 	return 0;
463 
464 fail_irq:
465 	irq_domain_remove(twl6030_irq->irq_domain);
466 	return status;
467 }
468 
469 int twl6030_exit_irq(void)
470 {
471 	if (twl6030_irq && twl6030_irq->twl_irq) {
472 		unregister_pm_notifier(&twl6030_irq->pm_nb);
473 		free_irq(twl6030_irq->twl_irq, NULL);
474 		/*
475 		 * TODO: IRQ domain and allocated nested IRQ descriptors
476 		 * should be freed somehow here. Now It can't be done, because
477 		 * child devices will not be deleted during removing of
478 		 * TWL Core driver and they will still contain allocated
479 		 * virt IRQs in their Resources tables.
480 		 * The same prevents us from using devm_request_threaded_irq()
481 		 * in this module.
482 		 */
483 	}
484 	return 0;
485 }
486 
487