xref: /openbmc/linux/drivers/mfd/twl6030-irq.c (revision fb574682)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * twl6030-irq.c - TWL6030 irq support
4  *
5  * Copyright (C) 2005-2009 Texas Instruments, Inc.
6  *
7  * Modifications to defer interrupt handling to a kernel thread:
8  * Copyright (C) 2006 MontaVista Software, Inc.
9  *
10  * Based on tlv320aic23.c:
11  * Copyright (c) by Kai Svahn <kai.svahn@nokia.com>
12  *
13  * Code cleanup and modifications to IRQ handler.
14  * by syed khasim <x0khasim@ti.com>
15  *
16  * TWL6030 specific code and IRQ handling changes by
17  * Jagadeesh Bhaskar Pakaravoor <j-pakaravoor@ti.com>
18  * Balaji T K <balajitk@ti.com>
19  */
20 
21 #include <linux/export.h>
22 #include <linux/interrupt.h>
23 #include <linux/irq.h>
24 #include <linux/kthread.h>
25 #include <linux/mfd/twl.h>
26 #include <linux/platform_device.h>
27 #include <linux/suspend.h>
28 #include <linux/of.h>
29 #include <linux/irqdomain.h>
30 #include <linux/of_device.h>
31 
32 #include "twl-core.h"
33 
34 /*
35  * TWL6030 (unlike its predecessors, which had two level interrupt handling)
36  * three interrupt registers INT_STS_A, INT_STS_B and INT_STS_C.
37  * It exposes status bits saying who has raised an interrupt. There are
38  * three mask registers that corresponds to these status registers, that
39  * enables/disables these interrupts.
40  *
41  * We set up IRQs starting at a platform-specified base. An interrupt map table,
42  * specifies mapping between interrupt number and the associated module.
43  */
44 #define TWL6030_NR_IRQS    20
45 
46 static int twl6030_interrupt_mapping[24] = {
47 	PWR_INTR_OFFSET,	/* Bit 0	PWRON			*/
48 	PWR_INTR_OFFSET,	/* Bit 1	RPWRON			*/
49 	PWR_INTR_OFFSET,	/* Bit 2	BAT_VLOW		*/
50 	RTC_INTR_OFFSET,	/* Bit 3	RTC_ALARM		*/
51 	RTC_INTR_OFFSET,	/* Bit 4	RTC_PERIOD		*/
52 	HOTDIE_INTR_OFFSET,	/* Bit 5	HOT_DIE			*/
53 	SMPSLDO_INTR_OFFSET,	/* Bit 6	VXXX_SHORT		*/
54 	SMPSLDO_INTR_OFFSET,	/* Bit 7	VMMC_SHORT		*/
55 
56 	SMPSLDO_INTR_OFFSET,	/* Bit 8	VUSIM_SHORT		*/
57 	BATDETECT_INTR_OFFSET,	/* Bit 9	BAT			*/
58 	SIMDETECT_INTR_OFFSET,	/* Bit 10	SIM			*/
59 	MMCDETECT_INTR_OFFSET,	/* Bit 11	MMC			*/
60 	RSV_INTR_OFFSET,	/* Bit 12	Reserved		*/
61 	MADC_INTR_OFFSET,	/* Bit 13	GPADC_RT_EOC		*/
62 	MADC_INTR_OFFSET,	/* Bit 14	GPADC_SW_EOC		*/
63 	GASGAUGE_INTR_OFFSET,	/* Bit 15	CC_AUTOCAL		*/
64 
65 	USBOTG_INTR_OFFSET,	/* Bit 16	ID_WKUP			*/
66 	USBOTG_INTR_OFFSET,	/* Bit 17	VBUS_WKUP		*/
67 	USBOTG_INTR_OFFSET,	/* Bit 18	ID			*/
68 	USB_PRES_INTR_OFFSET,	/* Bit 19	VBUS			*/
69 	CHARGER_INTR_OFFSET,	/* Bit 20	CHRG_CTRL		*/
70 	CHARGERFAULT_INTR_OFFSET,	/* Bit 21	EXT_CHRG	*/
71 	CHARGERFAULT_INTR_OFFSET,	/* Bit 22	INT_CHRG	*/
72 	RSV_INTR_OFFSET,	/* Bit 23	Reserved		*/
73 };
74 
75 static int twl6032_interrupt_mapping[24] = {
76 	PWR_INTR_OFFSET,	/* Bit 0	PWRON			*/
77 	PWR_INTR_OFFSET,	/* Bit 1	RPWRON			*/
78 	PWR_INTR_OFFSET,	/* Bit 2	SYS_VLOW		*/
79 	RTC_INTR_OFFSET,	/* Bit 3	RTC_ALARM		*/
80 	RTC_INTR_OFFSET,	/* Bit 4	RTC_PERIOD		*/
81 	HOTDIE_INTR_OFFSET,	/* Bit 5	HOT_DIE			*/
82 	SMPSLDO_INTR_OFFSET,	/* Bit 6	VXXX_SHORT		*/
83 	PWR_INTR_OFFSET,	/* Bit 7	SPDURATION		*/
84 
85 	PWR_INTR_OFFSET,	/* Bit 8	WATCHDOG		*/
86 	BATDETECT_INTR_OFFSET,	/* Bit 9	BAT			*/
87 	SIMDETECT_INTR_OFFSET,	/* Bit 10	SIM			*/
88 	MMCDETECT_INTR_OFFSET,	/* Bit 11	MMC			*/
89 	MADC_INTR_OFFSET,	/* Bit 12	GPADC_RT_EOC		*/
90 	MADC_INTR_OFFSET,	/* Bit 13	GPADC_SW_EOC		*/
91 	GASGAUGE_INTR_OFFSET,	/* Bit 14	CC_EOC			*/
92 	GASGAUGE_INTR_OFFSET,	/* Bit 15	CC_AUTOCAL		*/
93 
94 	USBOTG_INTR_OFFSET,	/* Bit 16	ID_WKUP			*/
95 	USBOTG_INTR_OFFSET,	/* Bit 17	VBUS_WKUP		*/
96 	USBOTG_INTR_OFFSET,	/* Bit 18	ID			*/
97 	USB_PRES_INTR_OFFSET,	/* Bit 19	VBUS			*/
98 	CHARGER_INTR_OFFSET,	/* Bit 20	CHRG_CTRL		*/
99 	CHARGERFAULT_INTR_OFFSET,	/* Bit 21	EXT_CHRG	*/
100 	CHARGERFAULT_INTR_OFFSET,	/* Bit 22	INT_CHRG	*/
101 	RSV_INTR_OFFSET,	/* Bit 23	Reserved		*/
102 };
103 
104 /*----------------------------------------------------------------------*/
105 
106 struct twl6030_irq {
107 	unsigned int		irq_base;
108 	int			twl_irq;
109 	bool			irq_wake_enabled;
110 	atomic_t		wakeirqs;
111 	struct notifier_block	pm_nb;
112 	struct irq_chip		irq_chip;
113 	struct irq_domain	*irq_domain;
114 	const int		*irq_mapping_tbl;
115 };
116 
117 static struct twl6030_irq *twl6030_irq;
118 
119 static int twl6030_irq_pm_notifier(struct notifier_block *notifier,
120 				   unsigned long pm_event, void *unused)
121 {
122 	int chained_wakeups;
123 	struct twl6030_irq *pdata = container_of(notifier, struct twl6030_irq,
124 						  pm_nb);
125 
126 	switch (pm_event) {
127 	case PM_SUSPEND_PREPARE:
128 		chained_wakeups = atomic_read(&pdata->wakeirqs);
129 
130 		if (chained_wakeups && !pdata->irq_wake_enabled) {
131 			if (enable_irq_wake(pdata->twl_irq))
132 				pr_err("twl6030 IRQ wake enable failed\n");
133 			else
134 				pdata->irq_wake_enabled = true;
135 		} else if (!chained_wakeups && pdata->irq_wake_enabled) {
136 			disable_irq_wake(pdata->twl_irq);
137 			pdata->irq_wake_enabled = false;
138 		}
139 
140 		disable_irq(pdata->twl_irq);
141 		break;
142 
143 	case PM_POST_SUSPEND:
144 		enable_irq(pdata->twl_irq);
145 		break;
146 
147 	default:
148 		break;
149 	}
150 
151 	return NOTIFY_DONE;
152 }
153 
154 /*
155 * Threaded irq handler for the twl6030 interrupt.
156 * We query the interrupt controller in the twl6030 to determine
157 * which module is generating the interrupt request and call
158 * handle_nested_irq for that module.
159 */
160 static irqreturn_t twl6030_irq_thread(int irq, void *data)
161 {
162 	int i, ret;
163 	union {
164 		u8 bytes[4];
165 		__le32 int_sts;
166 	} sts;
167 	u32 int_sts; /* sts.int_sts converted to CPU endianness */
168 	struct twl6030_irq *pdata = data;
169 
170 	/* read INT_STS_A, B and C in one shot using a burst read */
171 	ret = twl_i2c_read(TWL_MODULE_PIH, sts.bytes, REG_INT_STS_A, 3);
172 	if (ret) {
173 		pr_warn("twl6030_irq: I2C error %d reading PIH ISR\n", ret);
174 		return IRQ_HANDLED;
175 	}
176 
177 	sts.bytes[3] = 0; /* Only 24 bits are valid*/
178 
179 	/*
180 	 * Since VBUS status bit is not reliable for VBUS disconnect
181 	 * use CHARGER VBUS detection status bit instead.
182 	 */
183 	if (sts.bytes[2] & 0x10)
184 		sts.bytes[2] |= 0x08;
185 
186 	int_sts = le32_to_cpu(sts.int_sts);
187 	for (i = 0; int_sts; int_sts >>= 1, i++)
188 		if (int_sts & 0x1) {
189 			int module_irq =
190 				irq_find_mapping(pdata->irq_domain,
191 						 pdata->irq_mapping_tbl[i]);
192 			if (module_irq)
193 				handle_nested_irq(module_irq);
194 			else
195 				pr_err("twl6030_irq: Unmapped PIH ISR %u detected\n",
196 				       i);
197 			pr_debug("twl6030_irq: PIH ISR %u, virq%u\n",
198 				 i, module_irq);
199 		}
200 
201 	/*
202 	 * NOTE:
203 	 * Simulation confirms that documentation is wrong w.r.t the
204 	 * interrupt status clear operation. A single *byte* write to
205 	 * any one of STS_A to STS_C register results in all three
206 	 * STS registers being reset. Since it does not matter which
207 	 * value is written, all three registers are cleared on a
208 	 * single byte write, so we just use 0x0 to clear.
209 	 */
210 	ret = twl_i2c_write_u8(TWL_MODULE_PIH, 0x00, REG_INT_STS_A);
211 	if (ret)
212 		pr_warn("twl6030_irq: I2C error in clearing PIH ISR\n");
213 
214 	return IRQ_HANDLED;
215 }
216 
217 /*----------------------------------------------------------------------*/
218 
219 static int twl6030_irq_set_wake(struct irq_data *d, unsigned int on)
220 {
221 	struct twl6030_irq *pdata = irq_data_get_irq_chip_data(d);
222 
223 	if (on)
224 		atomic_inc(&pdata->wakeirqs);
225 	else
226 		atomic_dec(&pdata->wakeirqs);
227 
228 	return 0;
229 }
230 
231 int twl6030_interrupt_unmask(u8 bit_mask, u8 offset)
232 {
233 	int ret;
234 	u8 unmask_value;
235 
236 	ret = twl_i2c_read_u8(TWL_MODULE_PIH, &unmask_value,
237 			REG_INT_STS_A + offset);
238 	unmask_value &= (~(bit_mask));
239 	ret |= twl_i2c_write_u8(TWL_MODULE_PIH, unmask_value,
240 			REG_INT_STS_A + offset); /* unmask INT_MSK_A/B/C */
241 	return ret;
242 }
243 EXPORT_SYMBOL(twl6030_interrupt_unmask);
244 
245 int twl6030_interrupt_mask(u8 bit_mask, u8 offset)
246 {
247 	int ret;
248 	u8 mask_value;
249 
250 	ret = twl_i2c_read_u8(TWL_MODULE_PIH, &mask_value,
251 			REG_INT_STS_A + offset);
252 	mask_value |= (bit_mask);
253 	ret |= twl_i2c_write_u8(TWL_MODULE_PIH, mask_value,
254 			REG_INT_STS_A + offset); /* mask INT_MSK_A/B/C */
255 	return ret;
256 }
257 EXPORT_SYMBOL(twl6030_interrupt_mask);
258 
259 int twl6030_mmc_card_detect_config(void)
260 {
261 	int ret;
262 	u8 reg_val = 0;
263 
264 	/* Unmasking the Card detect Interrupt line for MMC1 from Phoenix */
265 	twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
266 						REG_INT_MSK_LINE_B);
267 	twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
268 						REG_INT_MSK_STS_B);
269 	/*
270 	 * Initially Configuring MMC_CTRL for receiving interrupts &
271 	 * Card status on TWL6030 for MMC1
272 	 */
273 	ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &reg_val, TWL6030_MMCCTRL);
274 	if (ret < 0) {
275 		pr_err("twl6030: Failed to read MMCCTRL, error %d\n", ret);
276 		return ret;
277 	}
278 	reg_val &= ~VMMC_AUTO_OFF;
279 	reg_val |= SW_FC;
280 	ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val, TWL6030_MMCCTRL);
281 	if (ret < 0) {
282 		pr_err("twl6030: Failed to write MMCCTRL, error %d\n", ret);
283 		return ret;
284 	}
285 
286 	/* Configuring PullUp-PullDown register */
287 	ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &reg_val,
288 						TWL6030_CFG_INPUT_PUPD3);
289 	if (ret < 0) {
290 		pr_err("twl6030: Failed to read CFG_INPUT_PUPD3, error %d\n",
291 									ret);
292 		return ret;
293 	}
294 	reg_val &= ~(MMC_PU | MMC_PD);
295 	ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val,
296 						TWL6030_CFG_INPUT_PUPD3);
297 	if (ret < 0) {
298 		pr_err("twl6030: Failed to write CFG_INPUT_PUPD3, error %d\n",
299 									ret);
300 		return ret;
301 	}
302 
303 	return irq_find_mapping(twl6030_irq->irq_domain,
304 				 MMCDETECT_INTR_OFFSET);
305 }
306 EXPORT_SYMBOL(twl6030_mmc_card_detect_config);
307 
308 int twl6030_mmc_card_detect(struct device *dev, int slot)
309 {
310 	int ret = -EIO;
311 	u8 read_reg = 0;
312 	struct platform_device *pdev = to_platform_device(dev);
313 
314 	if (pdev->id) {
315 		/* TWL6030 provide's Card detect support for
316 		 * only MMC1 controller.
317 		 */
318 		pr_err("Unknown MMC controller %d in %s\n", pdev->id, __func__);
319 		return ret;
320 	}
321 	/*
322 	 * BIT0 of MMC_CTRL on TWL6030 provides card status for MMC1
323 	 * 0 - Card not present ,1 - Card present
324 	 */
325 	ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &read_reg,
326 						TWL6030_MMCCTRL);
327 	if (ret >= 0)
328 		ret = read_reg & STS_MMC;
329 	return ret;
330 }
331 EXPORT_SYMBOL(twl6030_mmc_card_detect);
332 
333 static int twl6030_irq_map(struct irq_domain *d, unsigned int virq,
334 			      irq_hw_number_t hwirq)
335 {
336 	struct twl6030_irq *pdata = d->host_data;
337 
338 	irq_set_chip_data(virq, pdata);
339 	irq_set_chip_and_handler(virq,  &pdata->irq_chip, handle_simple_irq);
340 	irq_set_nested_thread(virq, true);
341 	irq_set_parent(virq, pdata->twl_irq);
342 	irq_set_noprobe(virq);
343 
344 	return 0;
345 }
346 
347 static void twl6030_irq_unmap(struct irq_domain *d, unsigned int virq)
348 {
349 	irq_set_chip_and_handler(virq, NULL, NULL);
350 	irq_set_chip_data(virq, NULL);
351 }
352 
353 static const struct irq_domain_ops twl6030_irq_domain_ops = {
354 	.map	= twl6030_irq_map,
355 	.unmap	= twl6030_irq_unmap,
356 	.xlate	= irq_domain_xlate_onetwocell,
357 };
358 
359 static const struct of_device_id twl6030_of_match[] = {
360 	{.compatible = "ti,twl6030", &twl6030_interrupt_mapping},
361 	{.compatible = "ti,twl6032", &twl6032_interrupt_mapping},
362 	{ },
363 };
364 
365 int twl6030_init_irq(struct device *dev, int irq_num)
366 {
367 	struct			device_node *node = dev->of_node;
368 	int			nr_irqs;
369 	int			status;
370 	u8			mask[3];
371 	const struct of_device_id *of_id;
372 
373 	of_id = of_match_device(twl6030_of_match, dev);
374 	if (!of_id || !of_id->data) {
375 		dev_err(dev, "Unknown TWL device model\n");
376 		return -EINVAL;
377 	}
378 
379 	nr_irqs = TWL6030_NR_IRQS;
380 
381 	twl6030_irq = devm_kzalloc(dev, sizeof(*twl6030_irq), GFP_KERNEL);
382 	if (!twl6030_irq)
383 		return -ENOMEM;
384 
385 	mask[0] = 0xFF;
386 	mask[1] = 0xFF;
387 	mask[2] = 0xFF;
388 
389 	/* mask all int lines */
390 	status = twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_MSK_LINE_A, 3);
391 	/* mask all int sts */
392 	status |= twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_MSK_STS_A, 3);
393 	/* clear INT_STS_A,B,C */
394 	status |= twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_STS_A, 3);
395 
396 	if (status < 0) {
397 		dev_err(dev, "I2C err writing TWL_MODULE_PIH: %d\n", status);
398 		return status;
399 	}
400 
401 	/*
402 	 * install an irq handler for each of the modules;
403 	 * clone dummy irq_chip since PIH can't *do* anything
404 	 */
405 	twl6030_irq->irq_chip = dummy_irq_chip;
406 	twl6030_irq->irq_chip.name = "twl6030";
407 	twl6030_irq->irq_chip.irq_set_type = NULL;
408 	twl6030_irq->irq_chip.irq_set_wake = twl6030_irq_set_wake;
409 
410 	twl6030_irq->pm_nb.notifier_call = twl6030_irq_pm_notifier;
411 	atomic_set(&twl6030_irq->wakeirqs, 0);
412 	twl6030_irq->irq_mapping_tbl = of_id->data;
413 
414 	twl6030_irq->irq_domain =
415 		irq_domain_add_linear(node, nr_irqs,
416 				      &twl6030_irq_domain_ops, twl6030_irq);
417 	if (!twl6030_irq->irq_domain) {
418 		dev_err(dev, "Can't add irq_domain\n");
419 		return -ENOMEM;
420 	}
421 
422 	dev_info(dev, "PIH (irq %d) nested IRQs\n", irq_num);
423 
424 	/* install an irq handler to demultiplex the TWL6030 interrupt */
425 	status = request_threaded_irq(irq_num, NULL, twl6030_irq_thread,
426 				      IRQF_ONESHOT, "TWL6030-PIH", twl6030_irq);
427 	if (status < 0) {
428 		dev_err(dev, "could not claim irq %d: %d\n", irq_num, status);
429 		goto fail_irq;
430 	}
431 
432 	twl6030_irq->twl_irq = irq_num;
433 	register_pm_notifier(&twl6030_irq->pm_nb);
434 	return 0;
435 
436 fail_irq:
437 	irq_domain_remove(twl6030_irq->irq_domain);
438 	return status;
439 }
440 
441 int twl6030_exit_irq(void)
442 {
443 	if (twl6030_irq && twl6030_irq->twl_irq) {
444 		unregister_pm_notifier(&twl6030_irq->pm_nb);
445 		free_irq(twl6030_irq->twl_irq, NULL);
446 		/*
447 		 * TODO: IRQ domain and allocated nested IRQ descriptors
448 		 * should be freed somehow here. Now It can't be done, because
449 		 * child devices will not be deleted during removing of
450 		 * TWL Core driver and they will still contain allocated
451 		 * virt IRQs in their Resources tables.
452 		 * The same prevents us from using devm_request_threaded_irq()
453 		 * in this module.
454 		 */
455 	}
456 	return 0;
457 }
458 
459