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1 /*
2  *  htc-i2cpld.c
3  *  Chip driver for an unknown CPLD chip found on omap850 HTC devices like
4  *  the HTC Wizard and HTC Herald.
5  *  The cpld is located on the i2c bus and acts as an input/output GPIO
6  *  extender.
7  *
8  *  Copyright (C) 2009 Cory Maccarrone <darkstar6262@gmail.com>
9  *
10  *  Based on work done in the linwizard project
11  *  Copyright (C) 2008-2009 Angelo Arrifano <miknix@gmail.com>
12  *
13  * This program is free software; you can redistribute it and/or modify
14  * it under the terms of the GNU General Public License as published by
15  * the Free Software Foundation; either version 2 of the License, or
16  * (at your option) any later version.
17  *
18  * This program is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21  * GNU General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with this program; if not, write to the Free Software
25  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26  */
27 
28 #include <linux/kernel.h>
29 #include <linux/init.h>
30 #include <linux/module.h>
31 #include <linux/interrupt.h>
32 #include <linux/platform_device.h>
33 #include <linux/i2c.h>
34 #include <linux/irq.h>
35 #include <linux/spinlock.h>
36 #include <linux/htcpld.h>
37 #include <linux/gpio.h>
38 #include <linux/slab.h>
39 
40 struct htcpld_chip {
41 	spinlock_t              lock;
42 
43 	/* chip info */
44 	u8                      reset;
45 	u8                      addr;
46 	struct device           *dev;
47 	struct i2c_client	*client;
48 
49 	/* Output details */
50 	u8                      cache_out;
51 	struct gpio_chip        chip_out;
52 
53 	/* Input details */
54 	u8                      cache_in;
55 	struct gpio_chip        chip_in;
56 
57 	u16                     irqs_enabled;
58 	uint                    irq_start;
59 	int                     nirqs;
60 
61 	unsigned int		flow_type;
62 	/*
63 	 * Work structure to allow for setting values outside of any
64 	 * possible interrupt context
65 	 */
66 	struct work_struct set_val_work;
67 };
68 
69 struct htcpld_data {
70 	/* irq info */
71 	u16                irqs_enabled;
72 	uint               irq_start;
73 	int                nirqs;
74 	uint               chained_irq;
75 	unsigned int       int_reset_gpio_hi;
76 	unsigned int       int_reset_gpio_lo;
77 
78 	/* htcpld info */
79 	struct htcpld_chip *chip;
80 	unsigned int       nchips;
81 };
82 
83 /* There does not appear to be a way to proactively mask interrupts
84  * on the htcpld chip itself.  So, we simply ignore interrupts that
85  * aren't desired. */
htcpld_mask(struct irq_data * data)86 static void htcpld_mask(struct irq_data *data)
87 {
88 	struct htcpld_chip *chip = irq_data_get_irq_chip_data(data);
89 	chip->irqs_enabled &= ~(1 << (data->irq - chip->irq_start));
90 	pr_debug("HTCPLD mask %d %04x\n", data->irq, chip->irqs_enabled);
91 }
htcpld_unmask(struct irq_data * data)92 static void htcpld_unmask(struct irq_data *data)
93 {
94 	struct htcpld_chip *chip = irq_data_get_irq_chip_data(data);
95 	chip->irqs_enabled |= 1 << (data->irq - chip->irq_start);
96 	pr_debug("HTCPLD unmask %d %04x\n", data->irq, chip->irqs_enabled);
97 }
98 
htcpld_set_type(struct irq_data * data,unsigned int flags)99 static int htcpld_set_type(struct irq_data *data, unsigned int flags)
100 {
101 	struct htcpld_chip *chip = irq_data_get_irq_chip_data(data);
102 
103 	if (flags & ~IRQ_TYPE_SENSE_MASK)
104 		return -EINVAL;
105 
106 	/* We only allow edge triggering */
107 	if (flags & (IRQ_TYPE_LEVEL_LOW|IRQ_TYPE_LEVEL_HIGH))
108 		return -EINVAL;
109 
110 	chip->flow_type = flags;
111 	return 0;
112 }
113 
114 static struct irq_chip htcpld_muxed_chip = {
115 	.name         = "htcpld",
116 	.irq_mask     = htcpld_mask,
117 	.irq_unmask   = htcpld_unmask,
118 	.irq_set_type = htcpld_set_type,
119 };
120 
121 /* To properly dispatch IRQ events, we need to read from the
122  * chip.  This is an I2C action that could possibly sleep
123  * (which is bad in interrupt context) -- so we use a threaded
124  * interrupt handler to get around that.
125  */
htcpld_handler(int irq,void * dev)126 static irqreturn_t htcpld_handler(int irq, void *dev)
127 {
128 	struct htcpld_data *htcpld = dev;
129 	unsigned int i;
130 	unsigned long flags;
131 	int irqpin;
132 
133 	if (!htcpld) {
134 		pr_debug("htcpld is null in ISR\n");
135 		return IRQ_HANDLED;
136 	}
137 
138 	/*
139 	 * For each chip, do a read of the chip and trigger any interrupts
140 	 * desired.  The interrupts will be triggered from LSB to MSB (i.e.
141 	 * bit 0 first, then bit 1, etc.)
142 	 *
143 	 * For chips that have no interrupt range specified, just skip 'em.
144 	 */
145 	for (i = 0; i < htcpld->nchips; i++) {
146 		struct htcpld_chip *chip = &htcpld->chip[i];
147 		struct i2c_client *client;
148 		int val;
149 		unsigned long uval, old_val;
150 
151 		if (!chip) {
152 			pr_debug("chip %d is null in ISR\n", i);
153 			continue;
154 		}
155 
156 		if (chip->nirqs == 0)
157 			continue;
158 
159 		client = chip->client;
160 		if (!client) {
161 			pr_debug("client %d is null in ISR\n", i);
162 			continue;
163 		}
164 
165 		/* Scan the chip */
166 		val = i2c_smbus_read_byte_data(client, chip->cache_out);
167 		if (val < 0) {
168 			/* Throw a warning and skip this chip */
169 			dev_warn(chip->dev, "Unable to read from chip: %d\n",
170 				 val);
171 			continue;
172 		}
173 
174 		uval = (unsigned long)val;
175 
176 		spin_lock_irqsave(&chip->lock, flags);
177 
178 		/* Save away the old value so we can compare it */
179 		old_val = chip->cache_in;
180 
181 		/* Write the new value */
182 		chip->cache_in = uval;
183 
184 		spin_unlock_irqrestore(&chip->lock, flags);
185 
186 		/*
187 		 * For each bit in the data (starting at bit 0), trigger
188 		 * associated interrupts.
189 		 */
190 		for (irqpin = 0; irqpin < chip->nirqs; irqpin++) {
191 			unsigned oldb, newb, type = chip->flow_type;
192 
193 			irq = chip->irq_start + irqpin;
194 
195 			/* Run the IRQ handler, but only if the bit value
196 			 * changed, and the proper flags are set */
197 			oldb = (old_val >> irqpin) & 1;
198 			newb = (uval >> irqpin) & 1;
199 
200 			if ((!oldb && newb && (type & IRQ_TYPE_EDGE_RISING)) ||
201 			    (oldb && !newb && (type & IRQ_TYPE_EDGE_FALLING))) {
202 				pr_debug("fire IRQ %d\n", irqpin);
203 				generic_handle_irq(irq);
204 			}
205 		}
206 	}
207 
208 	/*
209 	 * In order to continue receiving interrupts, the int_reset_gpio must
210 	 * be asserted.
211 	 */
212 	if (htcpld->int_reset_gpio_hi)
213 		gpio_set_value(htcpld->int_reset_gpio_hi, 1);
214 	if (htcpld->int_reset_gpio_lo)
215 		gpio_set_value(htcpld->int_reset_gpio_lo, 0);
216 
217 	return IRQ_HANDLED;
218 }
219 
220 /*
221  * The GPIO set routines can be called from interrupt context, especially if,
222  * for example they're attached to the led-gpio framework and a trigger is
223  * enabled.  As such, we declared work above in the htcpld_chip structure,
224  * and that work is scheduled in the set routine.  The kernel can then run
225  * the I2C functions, which will sleep, in process context.
226  */
htcpld_chip_set(struct gpio_chip * chip,unsigned offset,int val)227 static void htcpld_chip_set(struct gpio_chip *chip, unsigned offset, int val)
228 {
229 	struct i2c_client *client;
230 	struct htcpld_chip *chip_data;
231 	unsigned long flags;
232 
233 	chip_data = container_of(chip, struct htcpld_chip, chip_out);
234 	if (!chip_data)
235 		return;
236 
237 	client = chip_data->client;
238 	if (client == NULL)
239 		return;
240 
241 	spin_lock_irqsave(&chip_data->lock, flags);
242 	if (val)
243 		chip_data->cache_out |= (1 << offset);
244 	else
245 		chip_data->cache_out &= ~(1 << offset);
246 	spin_unlock_irqrestore(&chip_data->lock, flags);
247 
248 	schedule_work(&(chip_data->set_val_work));
249 }
250 
htcpld_chip_set_ni(struct work_struct * work)251 static void htcpld_chip_set_ni(struct work_struct *work)
252 {
253 	struct htcpld_chip *chip_data;
254 	struct i2c_client *client;
255 
256 	chip_data = container_of(work, struct htcpld_chip, set_val_work);
257 	client = chip_data->client;
258 	i2c_smbus_read_byte_data(client, chip_data->cache_out);
259 }
260 
htcpld_chip_get(struct gpio_chip * chip,unsigned offset)261 static int htcpld_chip_get(struct gpio_chip *chip, unsigned offset)
262 {
263 	struct htcpld_chip *chip_data;
264 	int val = 0;
265 	int is_input = 0;
266 
267 	/* Try out first */
268 	chip_data = container_of(chip, struct htcpld_chip, chip_out);
269 	if (!chip_data) {
270 		/* Try in */
271 		is_input = 1;
272 		chip_data = container_of(chip, struct htcpld_chip, chip_in);
273 		if (!chip_data)
274 			return -EINVAL;
275 	}
276 
277 	/* Determine if this is an input or output GPIO */
278 	if (!is_input)
279 		/* Use the output cache */
280 		val = (chip_data->cache_out >> offset) & 1;
281 	else
282 		/* Use the input cache */
283 		val = (chip_data->cache_in >> offset) & 1;
284 
285 	if (val)
286 		return 1;
287 	else
288 		return 0;
289 }
290 
htcpld_direction_output(struct gpio_chip * chip,unsigned offset,int value)291 static int htcpld_direction_output(struct gpio_chip *chip,
292 					unsigned offset, int value)
293 {
294 	htcpld_chip_set(chip, offset, value);
295 	return 0;
296 }
297 
htcpld_direction_input(struct gpio_chip * chip,unsigned offset)298 static int htcpld_direction_input(struct gpio_chip *chip,
299 					unsigned offset)
300 {
301 	/*
302 	 * No-op: this function can only be called on the input chip.
303 	 * We do however make sure the offset is within range.
304 	 */
305 	return (offset < chip->ngpio) ? 0 : -EINVAL;
306 }
307 
htcpld_chip_to_irq(struct gpio_chip * chip,unsigned offset)308 static int htcpld_chip_to_irq(struct gpio_chip *chip, unsigned offset)
309 {
310 	struct htcpld_chip *chip_data;
311 
312 	chip_data = container_of(chip, struct htcpld_chip, chip_in);
313 
314 	if (offset < chip_data->nirqs)
315 		return chip_data->irq_start + offset;
316 	else
317 		return -EINVAL;
318 }
319 
htcpld_chip_reset(struct i2c_client * client)320 static void htcpld_chip_reset(struct i2c_client *client)
321 {
322 	struct htcpld_chip *chip_data = i2c_get_clientdata(client);
323 	if (!chip_data)
324 		return;
325 
326 	i2c_smbus_read_byte_data(
327 		client, (chip_data->cache_out = chip_data->reset));
328 }
329 
htcpld_setup_chip_irq(struct platform_device * pdev,int chip_index)330 static int htcpld_setup_chip_irq(
331 		struct platform_device *pdev,
332 		int chip_index)
333 {
334 	struct htcpld_data *htcpld;
335 	struct device *dev = &pdev->dev;
336 	struct htcpld_core_platform_data *pdata;
337 	struct htcpld_chip *chip;
338 	struct htcpld_chip_platform_data *plat_chip_data;
339 	unsigned int irq, irq_end;
340 	int ret = 0;
341 
342 	/* Get the platform and driver data */
343 	pdata = dev->platform_data;
344 	htcpld = platform_get_drvdata(pdev);
345 	chip = &htcpld->chip[chip_index];
346 	plat_chip_data = &pdata->chip[chip_index];
347 
348 	/* Setup irq handlers */
349 	irq_end = chip->irq_start + chip->nirqs;
350 	for (irq = chip->irq_start; irq < irq_end; irq++) {
351 		irq_set_chip_and_handler(irq, &htcpld_muxed_chip,
352 					 handle_simple_irq);
353 		irq_set_chip_data(irq, chip);
354 #ifdef CONFIG_ARM
355 		set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
356 #else
357 		irq_set_probe(irq);
358 #endif
359 	}
360 
361 	return ret;
362 }
363 
htcpld_register_chip_i2c(struct platform_device * pdev,int chip_index)364 static int htcpld_register_chip_i2c(
365 		struct platform_device *pdev,
366 		int chip_index)
367 {
368 	struct htcpld_data *htcpld;
369 	struct device *dev = &pdev->dev;
370 	struct htcpld_core_platform_data *pdata;
371 	struct htcpld_chip *chip;
372 	struct htcpld_chip_platform_data *plat_chip_data;
373 	struct i2c_adapter *adapter;
374 	struct i2c_client *client;
375 	struct i2c_board_info info;
376 
377 	/* Get the platform and driver data */
378 	pdata = dev->platform_data;
379 	htcpld = platform_get_drvdata(pdev);
380 	chip = &htcpld->chip[chip_index];
381 	plat_chip_data = &pdata->chip[chip_index];
382 
383 	adapter = i2c_get_adapter(pdata->i2c_adapter_id);
384 	if (adapter == NULL) {
385 		/* Eek, no such I2C adapter!  Bail out. */
386 		dev_warn(dev, "Chip at i2c address 0x%x: Invalid i2c adapter %d\n",
387 			 plat_chip_data->addr, pdata->i2c_adapter_id);
388 		return -ENODEV;
389 	}
390 
391 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA)) {
392 		dev_warn(dev, "i2c adapter %d non-functional\n",
393 			 pdata->i2c_adapter_id);
394 		return -EINVAL;
395 	}
396 
397 	memset(&info, 0, sizeof(struct i2c_board_info));
398 	info.addr = plat_chip_data->addr;
399 	strlcpy(info.type, "htcpld-chip", I2C_NAME_SIZE);
400 	info.platform_data = chip;
401 
402 	/* Add the I2C device.  This calls the probe() function. */
403 	client = i2c_new_device(adapter, &info);
404 	if (!client) {
405 		/* I2C device registration failed, contineu with the next */
406 		dev_warn(dev, "Unable to add I2C device for 0x%x\n",
407 			 plat_chip_data->addr);
408 		return -ENODEV;
409 	}
410 
411 	i2c_set_clientdata(client, chip);
412 	snprintf(client->name, I2C_NAME_SIZE, "Chip_0x%d", client->addr);
413 	chip->client = client;
414 
415 	/* Reset the chip */
416 	htcpld_chip_reset(client);
417 	chip->cache_in = i2c_smbus_read_byte_data(client, chip->cache_out);
418 
419 	return 0;
420 }
421 
htcpld_unregister_chip_i2c(struct platform_device * pdev,int chip_index)422 static void htcpld_unregister_chip_i2c(
423 		struct platform_device *pdev,
424 		int chip_index)
425 {
426 	struct htcpld_data *htcpld;
427 	struct htcpld_chip *chip;
428 
429 	/* Get the platform and driver data */
430 	htcpld = platform_get_drvdata(pdev);
431 	chip = &htcpld->chip[chip_index];
432 
433 	if (chip->client)
434 		i2c_unregister_device(chip->client);
435 }
436 
htcpld_register_chip_gpio(struct platform_device * pdev,int chip_index)437 static int htcpld_register_chip_gpio(
438 		struct platform_device *pdev,
439 		int chip_index)
440 {
441 	struct htcpld_data *htcpld;
442 	struct device *dev = &pdev->dev;
443 	struct htcpld_core_platform_data *pdata;
444 	struct htcpld_chip *chip;
445 	struct htcpld_chip_platform_data *plat_chip_data;
446 	struct gpio_chip *gpio_chip;
447 	int ret = 0;
448 
449 	/* Get the platform and driver data */
450 	pdata = dev->platform_data;
451 	htcpld = platform_get_drvdata(pdev);
452 	chip = &htcpld->chip[chip_index];
453 	plat_chip_data = &pdata->chip[chip_index];
454 
455 	/* Setup the GPIO chips */
456 	gpio_chip = &(chip->chip_out);
457 	gpio_chip->label           = "htcpld-out";
458 	gpio_chip->dev             = dev;
459 	gpio_chip->owner           = THIS_MODULE;
460 	gpio_chip->get             = htcpld_chip_get;
461 	gpio_chip->set             = htcpld_chip_set;
462 	gpio_chip->direction_input = NULL;
463 	gpio_chip->direction_output = htcpld_direction_output;
464 	gpio_chip->base            = plat_chip_data->gpio_out_base;
465 	gpio_chip->ngpio           = plat_chip_data->num_gpios;
466 
467 	gpio_chip = &(chip->chip_in);
468 	gpio_chip->label           = "htcpld-in";
469 	gpio_chip->dev             = dev;
470 	gpio_chip->owner           = THIS_MODULE;
471 	gpio_chip->get             = htcpld_chip_get;
472 	gpio_chip->set             = NULL;
473 	gpio_chip->direction_input = htcpld_direction_input;
474 	gpio_chip->direction_output = NULL;
475 	gpio_chip->to_irq          = htcpld_chip_to_irq;
476 	gpio_chip->base            = plat_chip_data->gpio_in_base;
477 	gpio_chip->ngpio           = plat_chip_data->num_gpios;
478 
479 	/* Add the GPIO chips */
480 	ret = gpiochip_add(&(chip->chip_out));
481 	if (ret) {
482 		dev_warn(dev, "Unable to register output GPIOs for 0x%x: %d\n",
483 			 plat_chip_data->addr, ret);
484 		return ret;
485 	}
486 
487 	ret = gpiochip_add(&(chip->chip_in));
488 	if (ret) {
489 		int error;
490 
491 		dev_warn(dev, "Unable to register input GPIOs for 0x%x: %d\n",
492 			 plat_chip_data->addr, ret);
493 
494 		error = gpiochip_remove(&(chip->chip_out));
495 		if (error)
496 			dev_warn(dev, "Error while trying to unregister gpio chip: %d\n", error);
497 
498 		return ret;
499 	}
500 
501 	return 0;
502 }
503 
htcpld_setup_chips(struct platform_device * pdev)504 static int htcpld_setup_chips(struct platform_device *pdev)
505 {
506 	struct htcpld_data *htcpld;
507 	struct device *dev = &pdev->dev;
508 	struct htcpld_core_platform_data *pdata;
509 	int i;
510 
511 	/* Get the platform and driver data */
512 	pdata = dev->platform_data;
513 	htcpld = platform_get_drvdata(pdev);
514 
515 	/* Setup each chip's output GPIOs */
516 	htcpld->nchips = pdata->num_chip;
517 	htcpld->chip = kzalloc(sizeof(struct htcpld_chip) * htcpld->nchips,
518 			       GFP_KERNEL);
519 	if (!htcpld->chip) {
520 		dev_warn(dev, "Unable to allocate memory for chips\n");
521 		return -ENOMEM;
522 	}
523 
524 	/* Add the chips as best we can */
525 	for (i = 0; i < htcpld->nchips; i++) {
526 		int ret;
527 
528 		/* Setup the HTCPLD chips */
529 		htcpld->chip[i].reset = pdata->chip[i].reset;
530 		htcpld->chip[i].cache_out = pdata->chip[i].reset;
531 		htcpld->chip[i].cache_in = 0;
532 		htcpld->chip[i].dev = dev;
533 		htcpld->chip[i].irq_start = pdata->chip[i].irq_base;
534 		htcpld->chip[i].nirqs = pdata->chip[i].num_irqs;
535 
536 		INIT_WORK(&(htcpld->chip[i].set_val_work), &htcpld_chip_set_ni);
537 		spin_lock_init(&(htcpld->chip[i].lock));
538 
539 		/* Setup the interrupts for the chip */
540 		if (htcpld->chained_irq) {
541 			ret = htcpld_setup_chip_irq(pdev, i);
542 			if (ret)
543 				continue;
544 		}
545 
546 		/* Register the chip with I2C */
547 		ret = htcpld_register_chip_i2c(pdev, i);
548 		if (ret)
549 			continue;
550 
551 
552 		/* Register the chips with the GPIO subsystem */
553 		ret = htcpld_register_chip_gpio(pdev, i);
554 		if (ret) {
555 			/* Unregister the chip from i2c and continue */
556 			htcpld_unregister_chip_i2c(pdev, i);
557 			continue;
558 		}
559 
560 		dev_info(dev, "Registered chip at 0x%x\n", pdata->chip[i].addr);
561 	}
562 
563 	return 0;
564 }
565 
htcpld_core_probe(struct platform_device * pdev)566 static int htcpld_core_probe(struct platform_device *pdev)
567 {
568 	struct htcpld_data *htcpld;
569 	struct device *dev = &pdev->dev;
570 	struct htcpld_core_platform_data *pdata;
571 	struct resource *res;
572 	int ret = 0;
573 
574 	if (!dev)
575 		return -ENODEV;
576 
577 	pdata = dev->platform_data;
578 	if (!pdata) {
579 		dev_warn(dev, "Platform data not found for htcpld core!\n");
580 		return -ENXIO;
581 	}
582 
583 	htcpld = kzalloc(sizeof(struct htcpld_data), GFP_KERNEL);
584 	if (!htcpld)
585 		return -ENOMEM;
586 
587 	/* Find chained irq */
588 	ret = -EINVAL;
589 	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
590 	if (res) {
591 		int flags;
592 		htcpld->chained_irq = res->start;
593 
594 		/* Setup the chained interrupt handler */
595 		flags = IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING;
596 		ret = request_threaded_irq(htcpld->chained_irq,
597 					   NULL, htcpld_handler,
598 					   flags, pdev->name, htcpld);
599 		if (ret) {
600 			dev_warn(dev, "Unable to setup chained irq handler: %d\n", ret);
601 			goto fail;
602 		} else
603 			device_init_wakeup(dev, 0);
604 	}
605 
606 	/* Set the driver data */
607 	platform_set_drvdata(pdev, htcpld);
608 
609 	/* Setup the htcpld chips */
610 	ret = htcpld_setup_chips(pdev);
611 	if (ret)
612 		goto fail;
613 
614 	/* Request the GPIO(s) for the int reset and set them up */
615 	if (pdata->int_reset_gpio_hi) {
616 		ret = gpio_request(pdata->int_reset_gpio_hi, "htcpld-core");
617 		if (ret) {
618 			/*
619 			 * If it failed, that sucks, but we can probably
620 			 * continue on without it.
621 			 */
622 			dev_warn(dev, "Unable to request int_reset_gpio_hi -- interrupts may not work\n");
623 			htcpld->int_reset_gpio_hi = 0;
624 		} else {
625 			htcpld->int_reset_gpio_hi = pdata->int_reset_gpio_hi;
626 			gpio_set_value(htcpld->int_reset_gpio_hi, 1);
627 		}
628 	}
629 
630 	if (pdata->int_reset_gpio_lo) {
631 		ret = gpio_request(pdata->int_reset_gpio_lo, "htcpld-core");
632 		if (ret) {
633 			/*
634 			 * If it failed, that sucks, but we can probably
635 			 * continue on without it.
636 			 */
637 			dev_warn(dev, "Unable to request int_reset_gpio_lo -- interrupts may not work\n");
638 			htcpld->int_reset_gpio_lo = 0;
639 		} else {
640 			htcpld->int_reset_gpio_lo = pdata->int_reset_gpio_lo;
641 			gpio_set_value(htcpld->int_reset_gpio_lo, 0);
642 		}
643 	}
644 
645 	dev_info(dev, "Initialized successfully\n");
646 	return 0;
647 
648 fail:
649 	kfree(htcpld);
650 	return ret;
651 }
652 
653 /* The I2C Driver -- used internally */
654 static const struct i2c_device_id htcpld_chip_id[] = {
655 	{ "htcpld-chip", 0 },
656 	{ }
657 };
658 MODULE_DEVICE_TABLE(i2c, htcpld_chip_id);
659 
660 
661 static struct i2c_driver htcpld_chip_driver = {
662 	.driver = {
663 		.name	= "htcpld-chip",
664 	},
665 	.id_table = htcpld_chip_id,
666 };
667 
668 /* The Core Driver */
669 static struct platform_driver htcpld_core_driver = {
670 	.driver = {
671 		.name = "i2c-htcpld",
672 	},
673 };
674 
htcpld_core_init(void)675 static int __init htcpld_core_init(void)
676 {
677 	int ret;
678 
679 	/* Register the I2C Chip driver */
680 	ret = i2c_add_driver(&htcpld_chip_driver);
681 	if (ret)
682 		return ret;
683 
684 	/* Probe for our chips */
685 	return platform_driver_probe(&htcpld_core_driver, htcpld_core_probe);
686 }
687 
htcpld_core_exit(void)688 static void __exit htcpld_core_exit(void)
689 {
690 	i2c_del_driver(&htcpld_chip_driver);
691 	platform_driver_unregister(&htcpld_core_driver);
692 }
693 
694 module_init(htcpld_core_init);
695 module_exit(htcpld_core_exit);
696 
697 MODULE_AUTHOR("Cory Maccarrone <darkstar6262@gmail.com>");
698 MODULE_DESCRIPTION("I2C HTC PLD Driver");
699 MODULE_LICENSE("GPL");
700 
701