xref: /openbmc/linux/drivers/mfd/twl6030-irq.c (revision 8a10bc9d)
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 		__le32 int_sts;
180 	} sts;
181 	u32 int_sts; /* sts.int_sts converted to CPU endianness */
182 	struct twl6030_irq *pdata = data;
183 
184 	/* read INT_STS_A, B and C in one shot using a burst read */
185 	ret = twl_i2c_read(TWL_MODULE_PIH, sts.bytes, REG_INT_STS_A, 3);
186 	if (ret) {
187 		pr_warn("twl6030_irq: I2C error %d reading PIH ISR\n", ret);
188 		return IRQ_HANDLED;
189 	}
190 
191 	sts.bytes[3] = 0; /* Only 24 bits are valid*/
192 
193 	/*
194 	 * Since VBUS status bit is not reliable for VBUS disconnect
195 	 * use CHARGER VBUS detection status bit instead.
196 	 */
197 	if (sts.bytes[2] & 0x10)
198 		sts.bytes[2] |= 0x08;
199 
200 	int_sts = le32_to_cpu(sts.int_sts);
201 	for (i = 0; int_sts; int_sts >>= 1, i++)
202 		if (int_sts & 0x1) {
203 			int module_irq =
204 				irq_find_mapping(pdata->irq_domain,
205 						 pdata->irq_mapping_tbl[i]);
206 			if (module_irq)
207 				handle_nested_irq(module_irq);
208 			else
209 				pr_err("twl6030_irq: Unmapped PIH ISR %u detected\n",
210 				       i);
211 			pr_debug("twl6030_irq: PIH ISR %u, virq%u\n",
212 				 i, module_irq);
213 		}
214 
215 	/*
216 	 * NOTE:
217 	 * Simulation confirms that documentation is wrong w.r.t the
218 	 * interrupt status clear operation. A single *byte* write to
219 	 * any one of STS_A to STS_C register results in all three
220 	 * STS registers being reset. Since it does not matter which
221 	 * value is written, all three registers are cleared on a
222 	 * single byte write, so we just use 0x0 to clear.
223 	 */
224 	ret = twl_i2c_write_u8(TWL_MODULE_PIH, 0x00, REG_INT_STS_A);
225 	if (ret)
226 		pr_warn("twl6030_irq: I2C error in clearing PIH ISR\n");
227 
228 	return IRQ_HANDLED;
229 }
230 
231 /*----------------------------------------------------------------------*/
232 
233 static int twl6030_irq_set_wake(struct irq_data *d, unsigned int on)
234 {
235 	struct twl6030_irq *pdata = irq_get_chip_data(d->irq);
236 
237 	if (on)
238 		atomic_inc(&pdata->wakeirqs);
239 	else
240 		atomic_dec(&pdata->wakeirqs);
241 
242 	return 0;
243 }
244 
245 int twl6030_interrupt_unmask(u8 bit_mask, u8 offset)
246 {
247 	int ret;
248 	u8 unmask_value;
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 	ret = twl_i2c_read_u8(TWL_MODULE_PIH, &mask_value,
263 			REG_INT_STS_A + offset);
264 	mask_value |= (bit_mask);
265 	ret |= twl_i2c_write_u8(TWL_MODULE_PIH, mask_value,
266 			REG_INT_STS_A + offset); /* mask INT_MSK_A/B/C */
267 	return ret;
268 }
269 EXPORT_SYMBOL(twl6030_interrupt_mask);
270 
271 int twl6030_mmc_card_detect_config(void)
272 {
273 	int ret;
274 	u8 reg_val = 0;
275 
276 	/* Unmasking the Card detect Interrupt line for MMC1 from Phoenix */
277 	twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
278 						REG_INT_MSK_LINE_B);
279 	twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
280 						REG_INT_MSK_STS_B);
281 	/*
282 	 * Initially Configuring MMC_CTRL for receiving interrupts &
283 	 * Card status on TWL6030 for MMC1
284 	 */
285 	ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &reg_val, TWL6030_MMCCTRL);
286 	if (ret < 0) {
287 		pr_err("twl6030: Failed to read MMCCTRL, error %d\n", ret);
288 		return ret;
289 	}
290 	reg_val &= ~VMMC_AUTO_OFF;
291 	reg_val |= SW_FC;
292 	ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val, TWL6030_MMCCTRL);
293 	if (ret < 0) {
294 		pr_err("twl6030: Failed to write MMCCTRL, error %d\n", ret);
295 		return ret;
296 	}
297 
298 	/* Configuring PullUp-PullDown register */
299 	ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &reg_val,
300 						TWL6030_CFG_INPUT_PUPD3);
301 	if (ret < 0) {
302 		pr_err("twl6030: Failed to read CFG_INPUT_PUPD3, error %d\n",
303 									ret);
304 		return ret;
305 	}
306 	reg_val &= ~(MMC_PU | MMC_PD);
307 	ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val,
308 						TWL6030_CFG_INPUT_PUPD3);
309 	if (ret < 0) {
310 		pr_err("twl6030: Failed to write CFG_INPUT_PUPD3, error %d\n",
311 									ret);
312 		return ret;
313 	}
314 
315 	return irq_find_mapping(twl6030_irq->irq_domain,
316 				 MMCDETECT_INTR_OFFSET);
317 }
318 EXPORT_SYMBOL(twl6030_mmc_card_detect_config);
319 
320 int twl6030_mmc_card_detect(struct device *dev, int slot)
321 {
322 	int ret = -EIO;
323 	u8 read_reg = 0;
324 	struct platform_device *pdev = to_platform_device(dev);
325 
326 	if (pdev->id) {
327 		/* TWL6030 provide's Card detect support for
328 		 * only MMC1 controller.
329 		 */
330 		pr_err("Unknown MMC controller %d in %s\n", pdev->id, __func__);
331 		return ret;
332 	}
333 	/*
334 	 * BIT0 of MMC_CTRL on TWL6030 provides card status for MMC1
335 	 * 0 - Card not present ,1 - Card present
336 	 */
337 	ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &read_reg,
338 						TWL6030_MMCCTRL);
339 	if (ret >= 0)
340 		ret = read_reg & STS_MMC;
341 	return ret;
342 }
343 EXPORT_SYMBOL(twl6030_mmc_card_detect);
344 
345 static int twl6030_irq_map(struct irq_domain *d, unsigned int virq,
346 			      irq_hw_number_t hwirq)
347 {
348 	struct twl6030_irq *pdata = d->host_data;
349 
350 	irq_set_chip_data(virq, pdata);
351 	irq_set_chip_and_handler(virq,  &pdata->irq_chip, handle_simple_irq);
352 	irq_set_nested_thread(virq, true);
353 	irq_set_parent(virq, pdata->twl_irq);
354 
355 #ifdef CONFIG_ARM
356 	/*
357 	 * ARM requires an extra step to clear IRQ_NOREQUEST, which it
358 	 * sets on behalf of every irq_chip.  Also sets IRQ_NOPROBE.
359 	 */
360 	set_irq_flags(virq, IRQF_VALID);
361 #else
362 	/* same effect on other architectures */
363 	irq_set_noprobe(virq);
364 #endif
365 
366 	return 0;
367 }
368 
369 static void twl6030_irq_unmap(struct irq_domain *d, unsigned int virq)
370 {
371 #ifdef CONFIG_ARM
372 	set_irq_flags(virq, 0);
373 #endif
374 	irq_set_chip_and_handler(virq, NULL, NULL);
375 	irq_set_chip_data(virq, NULL);
376 }
377 
378 static struct irq_domain_ops twl6030_irq_domain_ops = {
379 	.map	= twl6030_irq_map,
380 	.unmap	= twl6030_irq_unmap,
381 	.xlate	= irq_domain_xlate_onetwocell,
382 };
383 
384 static const struct of_device_id twl6030_of_match[] = {
385 	{.compatible = "ti,twl6030", &twl6030_interrupt_mapping},
386 	{.compatible = "ti,twl6032", &twl6032_interrupt_mapping},
387 	{ },
388 };
389 
390 int twl6030_init_irq(struct device *dev, int irq_num)
391 {
392 	struct			device_node *node = dev->of_node;
393 	int			nr_irqs;
394 	int			status;
395 	u8			mask[3];
396 	const struct of_device_id *of_id;
397 
398 	of_id = of_match_device(twl6030_of_match, dev);
399 	if (!of_id || !of_id->data) {
400 		dev_err(dev, "Unknown TWL device model\n");
401 		return -EINVAL;
402 	}
403 
404 	nr_irqs = TWL6030_NR_IRQS;
405 
406 	twl6030_irq = devm_kzalloc(dev, sizeof(*twl6030_irq), GFP_KERNEL);
407 	if (!twl6030_irq) {
408 		dev_err(dev, "twl6030_irq: Memory allocation failed\n");
409 		return -ENOMEM;
410 	}
411 
412 	mask[0] = 0xFF;
413 	mask[1] = 0xFF;
414 	mask[2] = 0xFF;
415 
416 	/* mask all int lines */
417 	status = twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_MSK_LINE_A, 3);
418 	/* mask all int sts */
419 	status |= twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_MSK_STS_A, 3);
420 	/* clear INT_STS_A,B,C */
421 	status |= twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_STS_A, 3);
422 
423 	if (status < 0) {
424 		dev_err(dev, "I2C err writing TWL_MODULE_PIH: %d\n", status);
425 		return status;
426 	}
427 
428 	/*
429 	 * install an irq handler for each of the modules;
430 	 * clone dummy irq_chip since PIH can't *do* anything
431 	 */
432 	twl6030_irq->irq_chip = dummy_irq_chip;
433 	twl6030_irq->irq_chip.name = "twl6030";
434 	twl6030_irq->irq_chip.irq_set_type = NULL;
435 	twl6030_irq->irq_chip.irq_set_wake = twl6030_irq_set_wake;
436 
437 	twl6030_irq->pm_nb.notifier_call = twl6030_irq_pm_notifier;
438 	atomic_set(&twl6030_irq->wakeirqs, 0);
439 	twl6030_irq->irq_mapping_tbl = of_id->data;
440 
441 	twl6030_irq->irq_domain =
442 		irq_domain_add_linear(node, nr_irqs,
443 				      &twl6030_irq_domain_ops, twl6030_irq);
444 	if (!twl6030_irq->irq_domain) {
445 		dev_err(dev, "Can't add irq_domain\n");
446 		return -ENOMEM;
447 	}
448 
449 	dev_info(dev, "PIH (irq %d) nested IRQs\n", irq_num);
450 
451 	/* install an irq handler to demultiplex the TWL6030 interrupt */
452 	status = request_threaded_irq(irq_num, NULL, twl6030_irq_thread,
453 				      IRQF_ONESHOT, "TWL6030-PIH", twl6030_irq);
454 	if (status < 0) {
455 		dev_err(dev, "could not claim irq %d: %d\n", irq_num, status);
456 		goto fail_irq;
457 	}
458 
459 	twl6030_irq->twl_irq = irq_num;
460 	register_pm_notifier(&twl6030_irq->pm_nb);
461 	return 0;
462 
463 fail_irq:
464 	irq_domain_remove(twl6030_irq->irq_domain);
465 	return status;
466 }
467 
468 int twl6030_exit_irq(void)
469 {
470 	if (twl6030_irq && twl6030_irq->twl_irq) {
471 		unregister_pm_notifier(&twl6030_irq->pm_nb);
472 		free_irq(twl6030_irq->twl_irq, NULL);
473 		/*
474 		 * TODO: IRQ domain and allocated nested IRQ descriptors
475 		 * should be freed somehow here. Now It can't be done, because
476 		 * child devices will not be deleted during removing of
477 		 * TWL Core driver and they will still contain allocated
478 		 * virt IRQs in their Resources tables.
479 		 * The same prevents us from using devm_request_threaded_irq()
480 		 * in this module.
481 		 */
482 	}
483 	return 0;
484 }
485 
486