deec3ec858bf8125af6e76e282157df5ff5e3826
[platform/adaptation/renesas_rcar/renesas_kernel.git] / drivers / mfd / twl6030-irq.c
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/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
42 #include "twl-core.h"
43
44 /*
45  * TWL6030 (unlike its predecessors, which had two level interrupt handling)
46  * three interrupt registers INT_STS_A, INT_STS_B and INT_STS_C.
47  * It exposes status bits saying who has raised an interrupt. There are
48  * three mask registers that corresponds to these status registers, that
49  * enables/disables these interrupts.
50  *
51  * We set up IRQs starting at a platform-specified base. An interrupt map table,
52  * specifies mapping between interrupt number and the associated module.
53  *
54  */
55
56 static int twl6030_interrupt_mapping[24] = {
57         PWR_INTR_OFFSET,        /* Bit 0        PWRON                   */
58         PWR_INTR_OFFSET,        /* Bit 1        RPWRON                  */
59         PWR_INTR_OFFSET,        /* Bit 2        BAT_VLOW                */
60         RTC_INTR_OFFSET,        /* Bit 3        RTC_ALARM               */
61         RTC_INTR_OFFSET,        /* Bit 4        RTC_PERIOD              */
62         HOTDIE_INTR_OFFSET,     /* Bit 5        HOT_DIE                 */
63         SMPSLDO_INTR_OFFSET,    /* Bit 6        VXXX_SHORT              */
64         SMPSLDO_INTR_OFFSET,    /* Bit 7        VMMC_SHORT              */
65
66         SMPSLDO_INTR_OFFSET,    /* Bit 8        VUSIM_SHORT             */
67         BATDETECT_INTR_OFFSET,  /* Bit 9        BAT                     */
68         SIMDETECT_INTR_OFFSET,  /* Bit 10       SIM                     */
69         MMCDETECT_INTR_OFFSET,  /* Bit 11       MMC                     */
70         RSV_INTR_OFFSET,        /* Bit 12       Reserved                */
71         MADC_INTR_OFFSET,       /* Bit 13       GPADC_RT_EOC            */
72         MADC_INTR_OFFSET,       /* Bit 14       GPADC_SW_EOC            */
73         GASGAUGE_INTR_OFFSET,   /* Bit 15       CC_AUTOCAL              */
74
75         USBOTG_INTR_OFFSET,     /* Bit 16       ID_WKUP                 */
76         USBOTG_INTR_OFFSET,     /* Bit 17       VBUS_WKUP               */
77         USBOTG_INTR_OFFSET,     /* Bit 18       ID                      */
78         USB_PRES_INTR_OFFSET,   /* Bit 19       VBUS                    */
79         CHARGER_INTR_OFFSET,    /* Bit 20       CHRG_CTRL               */
80         CHARGERFAULT_INTR_OFFSET,       /* Bit 21       EXT_CHRG        */
81         CHARGERFAULT_INTR_OFFSET,       /* Bit 22       INT_CHRG        */
82         RSV_INTR_OFFSET,        /* Bit 23       Reserved                */
83 };
84 /*----------------------------------------------------------------------*/
85
86 static unsigned twl6030_irq_base;
87 static int twl_irq;
88 static bool twl_irq_wake_enabled;
89
90 static struct completion irq_event;
91 static atomic_t twl6030_wakeirqs = ATOMIC_INIT(0);
92
93 static int twl6030_irq_pm_notifier(struct notifier_block *notifier,
94                                    unsigned long pm_event, void *unused)
95 {
96         int chained_wakeups;
97
98         switch (pm_event) {
99         case PM_SUSPEND_PREPARE:
100                 chained_wakeups = atomic_read(&twl6030_wakeirqs);
101
102                 if (chained_wakeups && !twl_irq_wake_enabled) {
103                         if (enable_irq_wake(twl_irq))
104                                 pr_err("twl6030 IRQ wake enable failed\n");
105                         else
106                                 twl_irq_wake_enabled = true;
107                 } else if (!chained_wakeups && twl_irq_wake_enabled) {
108                         disable_irq_wake(twl_irq);
109                         twl_irq_wake_enabled = false;
110                 }
111
112                 disable_irq(twl_irq);
113                 break;
114
115         case PM_POST_SUSPEND:
116                 enable_irq(twl_irq);
117                 break;
118
119         default:
120                 break;
121         }
122
123         return NOTIFY_DONE;
124 }
125
126 static struct notifier_block twl6030_irq_pm_notifier_block = {
127         .notifier_call = twl6030_irq_pm_notifier,
128 };
129
130 /*
131  * This thread processes interrupts reported by the Primary Interrupt Handler.
132  */
133 static int twl6030_irq_thread(void *data)
134 {
135         long irq = (long)data;
136         static unsigned i2c_errors;
137         static const unsigned max_i2c_errors = 100;
138         int ret;
139
140         current->flags |= PF_NOFREEZE;
141
142         while (!kthread_should_stop()) {
143                 int i;
144                 union {
145                 u8 bytes[4];
146                 u32 int_sts;
147                 } sts;
148
149                 /* Wait for IRQ, then read PIH irq status (also blocking) */
150                 wait_for_completion_interruptible(&irq_event);
151
152                 /* read INT_STS_A, B and C in one shot using a burst read */
153                 ret = twl_i2c_read(TWL_MODULE_PIH, sts.bytes,
154                                 REG_INT_STS_A, 3);
155                 if (ret) {
156                         pr_warning("twl6030: I2C error %d reading PIH ISR\n",
157                                         ret);
158                         if (++i2c_errors >= max_i2c_errors) {
159                                 printk(KERN_ERR "Maximum I2C error count"
160                                                 " exceeded.  Terminating %s.\n",
161                                                 __func__);
162                                 break;
163                         }
164                         complete(&irq_event);
165                         continue;
166                 }
167
168
169
170                 sts.bytes[3] = 0; /* Only 24 bits are valid*/
171
172                 /*
173                  * Since VBUS status bit is not reliable for VBUS disconnect
174                  * use CHARGER VBUS detection status bit instead.
175                  */
176                 if (sts.bytes[2] & 0x10)
177                         sts.bytes[2] |= 0x08;
178
179                 for (i = 0; sts.int_sts; sts.int_sts >>= 1, i++) {
180                         local_irq_disable();
181                         if (sts.int_sts & 0x1) {
182                                 int module_irq = twl6030_irq_base +
183                                         twl6030_interrupt_mapping[i];
184                                 generic_handle_irq(module_irq);
185
186                         }
187                 local_irq_enable();
188                 }
189                 ret = twl_i2c_write(TWL_MODULE_PIH, sts.bytes,
190                                 REG_INT_STS_A, 3); /* clear INT_STS_A */
191                 if (ret)
192                         pr_warning("twl6030: I2C error in clearing PIH ISR\n");
193
194                 enable_irq(irq);
195         }
196
197         return 0;
198 }
199
200 /*
201  * handle_twl6030_int() is the desc->handle method for the twl6030 interrupt.
202  * This is a chained interrupt, so there is no desc->action method for it.
203  * Now we need to query the interrupt controller in the twl6030 to determine
204  * which module is generating the interrupt request.  However, we can't do i2c
205  * transactions in interrupt context, so we must defer that work to a kernel
206  * thread.  All we do here is acknowledge and mask the interrupt and wakeup
207  * the kernel thread.
208  */
209 static irqreturn_t handle_twl6030_pih(int irq, void *devid)
210 {
211         disable_irq_nosync(irq);
212         complete(devid);
213         return IRQ_HANDLED;
214 }
215
216 /*----------------------------------------------------------------------*/
217
218 static inline void activate_irq(int irq)
219 {
220 #ifdef CONFIG_ARM
221         /* ARM requires an extra step to clear IRQ_NOREQUEST, which it
222          * sets on behalf of every irq_chip.  Also sets IRQ_NOPROBE.
223          */
224         set_irq_flags(irq, IRQF_VALID);
225 #else
226         /* same effect on other architectures */
227         irq_set_noprobe(irq);
228 #endif
229 }
230
231 int twl6030_irq_set_wake(struct irq_data *d, unsigned int on)
232 {
233         if (on)
234                 atomic_inc(&twl6030_wakeirqs);
235         else
236                 atomic_dec(&twl6030_wakeirqs);
237
238         return 0;
239 }
240
241 /*----------------------------------------------------------------------*/
242
243 static unsigned twl6030_irq_next;
244
245 /*----------------------------------------------------------------------*/
246 int twl6030_interrupt_unmask(u8 bit_mask, u8 offset)
247 {
248         int ret;
249         u8 unmask_value;
250         ret = twl_i2c_read_u8(TWL_MODULE_PIH, &unmask_value,
251                         REG_INT_STS_A + offset);
252         unmask_value &= (~(bit_mask));
253         ret |= twl_i2c_write_u8(TWL_MODULE_PIH, unmask_value,
254                         REG_INT_STS_A + offset); /* unmask INT_MSK_A/B/C */
255         return ret;
256 }
257 EXPORT_SYMBOL(twl6030_interrupt_unmask);
258
259 int twl6030_interrupt_mask(u8 bit_mask, u8 offset)
260 {
261         int ret;
262         u8 mask_value;
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         return 0;
316 }
317 EXPORT_SYMBOL(twl6030_mmc_card_detect_config);
318
319 int twl6030_mmc_card_detect(struct device *dev, int slot)
320 {
321         int ret = -EIO;
322         u8 read_reg = 0;
323         struct platform_device *pdev = to_platform_device(dev);
324
325         if (pdev->id) {
326                 /* TWL6030 provide's Card detect support for
327                  * only MMC1 controller.
328                  */
329                 pr_err("Unknown MMC controller %d in %s\n", pdev->id, __func__);
330                 return ret;
331         }
332         /*
333          * BIT0 of MMC_CTRL on TWL6030 provides card status for MMC1
334          * 0 - Card not present ,1 - Card present
335          */
336         ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &read_reg,
337                                                 TWL6030_MMCCTRL);
338         if (ret >= 0)
339                 ret = read_reg & STS_MMC;
340         return ret;
341 }
342 EXPORT_SYMBOL(twl6030_mmc_card_detect);
343
344 int twl6030_init_irq(int irq_num, unsigned irq_base, unsigned irq_end)
345 {
346
347         int     status = 0;
348         int     i;
349         struct task_struct      *task;
350         int ret;
351         u8 mask[4];
352
353         static struct irq_chip  twl6030_irq_chip;
354         mask[1] = 0xFF;
355         mask[2] = 0xFF;
356         mask[3] = 0xFF;
357         ret = twl_i2c_write(TWL_MODULE_PIH, &mask[0],
358                         REG_INT_MSK_LINE_A, 3); /* MASK ALL INT LINES */
359         ret = twl_i2c_write(TWL_MODULE_PIH, &mask[0],
360                         REG_INT_MSK_STS_A, 3); /* MASK ALL INT STS */
361         ret = twl_i2c_write(TWL_MODULE_PIH, &mask[0],
362                         REG_INT_STS_A, 3); /* clear INT_STS_A,B,C */
363
364         twl6030_irq_base = irq_base;
365
366         /* install an irq handler for each of the modules;
367          * clone dummy irq_chip since PIH can't *do* anything
368          */
369         twl6030_irq_chip = dummy_irq_chip;
370         twl6030_irq_chip.name = "twl6030";
371         twl6030_irq_chip.irq_set_type = NULL;
372         twl6030_irq_chip.irq_set_wake = twl6030_irq_set_wake;
373
374         for (i = irq_base; i < irq_end; i++) {
375                 irq_set_chip_and_handler(i, &twl6030_irq_chip,
376                                          handle_simple_irq);
377                 irq_set_chip_data(i, (void *)irq_num);
378                 activate_irq(i);
379         }
380
381         twl6030_irq_next = i;
382         pr_info("twl6030: %s (irq %d) chaining IRQs %d..%d\n", "PIH",
383                         irq_num, irq_base, twl6030_irq_next - 1);
384
385         /* install an irq handler to demultiplex the TWL6030 interrupt */
386         init_completion(&irq_event);
387
388         status = request_irq(irq_num, handle_twl6030_pih, 0,
389                                 "TWL6030-PIH", &irq_event);
390         if (status < 0) {
391                 pr_err("twl6030: could not claim irq%d: %d\n", irq_num, status);
392                 goto fail_irq;
393         }
394
395         task = kthread_run(twl6030_irq_thread, (void *)irq_num, "twl6030-irq");
396         if (IS_ERR(task)) {
397                 pr_err("twl6030: could not create irq %d thread!\n", irq_num);
398                 status = PTR_ERR(task);
399                 goto fail_kthread;
400         }
401
402         twl_irq = irq_num;
403         register_pm_notifier(&twl6030_irq_pm_notifier_block);
404         return status;
405
406 fail_kthread:
407         free_irq(irq_num, &irq_event);
408
409 fail_irq:
410         for (i = irq_base; i < irq_end; i++)
411                 irq_set_chip_and_handler(i, NULL, NULL);
412         return status;
413 }
414
415 int twl6030_exit_irq(void)
416 {
417         unregister_pm_notifier(&twl6030_irq_pm_notifier_block);
418
419         if (twl6030_irq_base) {
420                 pr_err("twl6030: can't yet clean up IRQs?\n");
421                 return -ENOSYS;
422         }
423         return 0;
424 }
425