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
41 #include "twl-core.h"
42
43 /*
44 * TWL6030 (unlike its predecessors, which had two level interrupt handling)
45 * three interrupt registers INT_STS_A, INT_STS_B and INT_STS_C.
46 * It exposes status bits saying who has raised an interrupt. There are
47 * three mask registers that corresponds to these status registers, that
48 * enables/disables these interrupts.
49 *
50 * We set up IRQs starting at a platform-specified base. An interrupt map table,
51 * specifies mapping between interrupt number and the associated module.
52 *
53 */
54
55 static int twl6030_interrupt_mapping[24] = {
56 PWR_INTR_OFFSET, /* Bit 0 PWRON */
57 PWR_INTR_OFFSET, /* Bit 1 RPWRON */
58 PWR_INTR_OFFSET, /* Bit 2 BAT_VLOW */
59 RTC_INTR_OFFSET, /* Bit 3 RTC_ALARM */
60 RTC_INTR_OFFSET, /* Bit 4 RTC_PERIOD */
61 HOTDIE_INTR_OFFSET, /* Bit 5 HOT_DIE */
62 SMPSLDO_INTR_OFFSET, /* Bit 6 VXXX_SHORT */
63 SMPSLDO_INTR_OFFSET, /* Bit 7 VMMC_SHORT */
64
65 SMPSLDO_INTR_OFFSET, /* Bit 8 VUSIM_SHORT */
66 BATDETECT_INTR_OFFSET, /* Bit 9 BAT */
67 SIMDETECT_INTR_OFFSET, /* Bit 10 SIM */
68 MMCDETECT_INTR_OFFSET, /* Bit 11 MMC */
69 RSV_INTR_OFFSET, /* Bit 12 Reserved */
70 MADC_INTR_OFFSET, /* Bit 13 GPADC_RT_EOC */
71 MADC_INTR_OFFSET, /* Bit 14 GPADC_SW_EOC */
72 GASGAUGE_INTR_OFFSET, /* Bit 15 CC_AUTOCAL */
73
74 USBOTG_INTR_OFFSET, /* Bit 16 ID_WKUP */
75 USBOTG_INTR_OFFSET, /* Bit 17 VBUS_WKUP */
76 USBOTG_INTR_OFFSET, /* Bit 18 ID */
77 USB_PRES_INTR_OFFSET, /* Bit 19 VBUS */
78 CHARGER_INTR_OFFSET, /* Bit 20 CHRG_CTRL */
79 CHARGER_INTR_OFFSET, /* Bit 21 EXT_CHRG */
80 CHARGER_INTR_OFFSET, /* Bit 22 INT_CHRG */
81 RSV_INTR_OFFSET, /* Bit 23 Reserved */
82 };
83 /*----------------------------------------------------------------------*/
84
85 static unsigned twl6030_irq_base;
86
87 static struct completion irq_event;
88
89 /*
90 * This thread processes interrupts reported by the Primary Interrupt Handler.
91 */
twl6030_irq_thread(void * data)92 static int twl6030_irq_thread(void *data)
93 {
94 long irq = (long)data;
95 static unsigned i2c_errors;
96 static const unsigned max_i2c_errors = 100;
97 int ret;
98
99 current->flags |= PF_NOFREEZE;
100
101 while (!kthread_should_stop()) {
102 int i;
103 union {
104 u8 bytes[4];
105 u32 int_sts;
106 } sts;
107
108 /* Wait for IRQ, then read PIH irq status (also blocking) */
109 wait_for_completion_interruptible(&irq_event);
110
111 /* read INT_STS_A, B and C in one shot using a burst read */
112 ret = twl_i2c_read(TWL_MODULE_PIH, sts.bytes,
113 REG_INT_STS_A, 3);
114 if (ret) {
115 pr_warning("twl6030: I2C error %d reading PIH ISR\n",
116 ret);
117 if (++i2c_errors >= max_i2c_errors) {
118 printk(KERN_ERR "Maximum I2C error count"
119 " exceeded. Terminating %s.\n",
120 __func__);
121 break;
122 }
123 complete(&irq_event);
124 continue;
125 }
126
127
128
129 sts.bytes[3] = 0; /* Only 24 bits are valid*/
130
131 /*
132 * Since VBUS status bit is not reliable for VBUS disconnect
133 * use CHARGER VBUS detection status bit instead.
134 */
135 if (sts.bytes[2] & 0x10)
136 sts.bytes[2] |= 0x08;
137
138 for (i = 0; sts.int_sts; sts.int_sts >>= 1, i++) {
139 local_irq_disable();
140 if (sts.int_sts & 0x1) {
141 int module_irq = twl6030_irq_base +
142 twl6030_interrupt_mapping[i];
143 generic_handle_irq(module_irq);
144
145 }
146 local_irq_enable();
147 }
148 ret = twl_i2c_write(TWL_MODULE_PIH, sts.bytes,
149 REG_INT_STS_A, 3); /* clear INT_STS_A */
150 if (ret)
151 pr_warning("twl6030: I2C error in clearing PIH ISR\n");
152
153 enable_irq(irq);
154 }
155
156 return 0;
157 }
158
159 /*
160 * handle_twl6030_int() is the desc->handle method for the twl6030 interrupt.
161 * This is a chained interrupt, so there is no desc->action method for it.
162 * Now we need to query the interrupt controller in the twl6030 to determine
163 * which module is generating the interrupt request. However, we can't do i2c
164 * transactions in interrupt context, so we must defer that work to a kernel
165 * thread. All we do here is acknowledge and mask the interrupt and wakeup
166 * the kernel thread.
167 */
handle_twl6030_pih(int irq,void * devid)168 static irqreturn_t handle_twl6030_pih(int irq, void *devid)
169 {
170 disable_irq_nosync(irq);
171 complete(devid);
172 return IRQ_HANDLED;
173 }
174
175 /*----------------------------------------------------------------------*/
176
activate_irq(int irq)177 static inline void activate_irq(int irq)
178 {
179 #ifdef CONFIG_ARM
180 /* ARM requires an extra step to clear IRQ_NOREQUEST, which it
181 * sets on behalf of every irq_chip. Also sets IRQ_NOPROBE.
182 */
183 set_irq_flags(irq, IRQF_VALID);
184 #else
185 /* same effect on other architectures */
186 irq_set_noprobe(irq);
187 #endif
188 }
189
190 /*----------------------------------------------------------------------*/
191
192 static unsigned twl6030_irq_next;
193
194 /*----------------------------------------------------------------------*/
twl6030_interrupt_unmask(u8 bit_mask,u8 offset)195 int twl6030_interrupt_unmask(u8 bit_mask, u8 offset)
196 {
197 int ret;
198 u8 unmask_value;
199 ret = twl_i2c_read_u8(TWL_MODULE_PIH, &unmask_value,
200 REG_INT_STS_A + offset);
201 unmask_value &= (~(bit_mask));
202 ret |= twl_i2c_write_u8(TWL_MODULE_PIH, unmask_value,
203 REG_INT_STS_A + offset); /* unmask INT_MSK_A/B/C */
204 return ret;
205 }
206 EXPORT_SYMBOL(twl6030_interrupt_unmask);
207
twl6030_interrupt_mask(u8 bit_mask,u8 offset)208 int twl6030_interrupt_mask(u8 bit_mask, u8 offset)
209 {
210 int ret;
211 u8 mask_value;
212 ret = twl_i2c_read_u8(TWL_MODULE_PIH, &mask_value,
213 REG_INT_STS_A + offset);
214 mask_value |= (bit_mask);
215 ret |= twl_i2c_write_u8(TWL_MODULE_PIH, mask_value,
216 REG_INT_STS_A + offset); /* mask INT_MSK_A/B/C */
217 return ret;
218 }
219 EXPORT_SYMBOL(twl6030_interrupt_mask);
220
twl6030_mmc_card_detect_config(void)221 int twl6030_mmc_card_detect_config(void)
222 {
223 int ret;
224 u8 reg_val = 0;
225
226 /* Unmasking the Card detect Interrupt line for MMC1 from Phoenix */
227 twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
228 REG_INT_MSK_LINE_B);
229 twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
230 REG_INT_MSK_STS_B);
231 /*
232 * Initially Configuring MMC_CTRL for receiving interrupts &
233 * Card status on TWL6030 for MMC1
234 */
235 ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, ®_val, TWL6030_MMCCTRL);
236 if (ret < 0) {
237 pr_err("twl6030: Failed to read MMCCTRL, error %d\n", ret);
238 return ret;
239 }
240 reg_val &= ~VMMC_AUTO_OFF;
241 reg_val |= SW_FC;
242 ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val, TWL6030_MMCCTRL);
243 if (ret < 0) {
244 pr_err("twl6030: Failed to write MMCCTRL, error %d\n", ret);
245 return ret;
246 }
247
248 /* Configuring PullUp-PullDown register */
249 ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, ®_val,
250 TWL6030_CFG_INPUT_PUPD3);
251 if (ret < 0) {
252 pr_err("twl6030: Failed to read CFG_INPUT_PUPD3, error %d\n",
253 ret);
254 return ret;
255 }
256 reg_val &= ~(MMC_PU | MMC_PD);
257 ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val,
258 TWL6030_CFG_INPUT_PUPD3);
259 if (ret < 0) {
260 pr_err("twl6030: Failed to write CFG_INPUT_PUPD3, error %d\n",
261 ret);
262 return ret;
263 }
264 return 0;
265 }
266 EXPORT_SYMBOL(twl6030_mmc_card_detect_config);
267
twl6030_mmc_card_detect(struct device * dev,int slot)268 int twl6030_mmc_card_detect(struct device *dev, int slot)
269 {
270 int ret = -EIO;
271 u8 read_reg = 0;
272 struct platform_device *pdev = to_platform_device(dev);
273
274 if (pdev->id) {
275 /* TWL6030 provide's Card detect support for
276 * only MMC1 controller.
277 */
278 pr_err("Unknown MMC controller %d in %s\n", pdev->id, __func__);
279 return ret;
280 }
281 /*
282 * BIT0 of MMC_CTRL on TWL6030 provides card status for MMC1
283 * 0 - Card not present ,1 - Card present
284 */
285 ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &read_reg,
286 TWL6030_MMCCTRL);
287 if (ret >= 0)
288 ret = read_reg & STS_MMC;
289 return ret;
290 }
291 EXPORT_SYMBOL(twl6030_mmc_card_detect);
292
twl6030_init_irq(int irq_num,unsigned irq_base,unsigned irq_end)293 int twl6030_init_irq(int irq_num, unsigned irq_base, unsigned irq_end)
294 {
295
296 int status = 0;
297 int i;
298 struct task_struct *task;
299 int ret;
300 u8 mask[4];
301
302 static struct irq_chip twl6030_irq_chip;
303 mask[1] = 0xFF;
304 mask[2] = 0xFF;
305 mask[3] = 0xFF;
306 ret = twl_i2c_write(TWL_MODULE_PIH, &mask[0],
307 REG_INT_MSK_LINE_A, 3); /* MASK ALL INT LINES */
308 ret = twl_i2c_write(TWL_MODULE_PIH, &mask[0],
309 REG_INT_MSK_STS_A, 3); /* MASK ALL INT STS */
310 ret = twl_i2c_write(TWL_MODULE_PIH, &mask[0],
311 REG_INT_STS_A, 3); /* clear INT_STS_A,B,C */
312
313 twl6030_irq_base = irq_base;
314
315 /* install an irq handler for each of the modules;
316 * clone dummy irq_chip since PIH can't *do* anything
317 */
318 twl6030_irq_chip = dummy_irq_chip;
319 twl6030_irq_chip.name = "twl6030";
320 twl6030_irq_chip.irq_set_type = NULL;
321
322 for (i = irq_base; i < irq_end; i++) {
323 irq_set_chip_and_handler(i, &twl6030_irq_chip,
324 handle_simple_irq);
325 activate_irq(i);
326 }
327
328 twl6030_irq_next = i;
329 pr_info("twl6030: %s (irq %d) chaining IRQs %d..%d\n", "PIH",
330 irq_num, irq_base, twl6030_irq_next - 1);
331
332 /* install an irq handler to demultiplex the TWL6030 interrupt */
333 init_completion(&irq_event);
334 task = kthread_run(twl6030_irq_thread, (void *)irq_num, "twl6030-irq");
335 if (IS_ERR(task)) {
336 pr_err("twl6030: could not create irq %d thread!\n", irq_num);
337 status = PTR_ERR(task);
338 goto fail_kthread;
339 }
340
341 status = request_irq(irq_num, handle_twl6030_pih, IRQF_DISABLED,
342 "TWL6030-PIH", &irq_event);
343 if (status < 0) {
344 pr_err("twl6030: could not claim irq%d: %d\n", irq_num, status);
345 goto fail_irq;
346 }
347 return status;
348 fail_irq:
349 free_irq(irq_num, &irq_event);
350
351 fail_kthread:
352 for (i = irq_base; i < irq_end; i++)
353 irq_set_chip_and_handler(i, NULL, NULL);
354 return status;
355 }
356
twl6030_exit_irq(void)357 int twl6030_exit_irq(void)
358 {
359
360 if (twl6030_irq_base) {
361 pr_err("twl6030: can't yet clean up IRQs?\n");
362 return -ENOSYS;
363 }
364 return 0;
365 }
366
367