summaryrefslogblamecommitdiffstats
path: root/drivers/mfd/twl4030-madc.c
blob: 456ecb5ac4fe52e1a5515f1793eda270c5407056 (plain) (tree)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512































































































































































































































































































































































































































































































































                                                                                
                                  
                               
 

















                                                                                
                         




                                                                                
                         








                                                                      
                                 






                                                                 
                                 






















































































































































                                                                                

                               






























                                                                               





















                                                                                












































                                                                              
                                            



                                         
                                      
/*
 *
 * TWL4030 MADC module driver-This driver monitors the real time
 * conversion of analog signals like battery temperature,
 * battery type, battery level etc.
 *
 * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
 * J Keerthy <j-keerthy@ti.com>
 *
 * Based on twl4030-madc.c
 * Copyright (C) 2008 Nokia Corporation
 * Mikko Ylinen <mikko.k.ylinen@nokia.com>
 *
 * Amit Kucheria <amit.kucheria@canonical.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 *
 */

#include <linux/init.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/i2c/twl.h>
#include <linux/i2c/twl4030-madc.h>
#include <linux/module.h>
#include <linux/stddef.h>
#include <linux/mutex.h>
#include <linux/bitops.h>
#include <linux/jiffies.h>
#include <linux/types.h>
#include <linux/gfp.h>
#include <linux/err.h>

/*
 * struct twl4030_madc_data - a container for madc info
 * @dev - pointer to device structure for madc
 * @lock - mutex protecting this data structure
 * @requests - Array of request struct corresponding to SW1, SW2 and RT
 * @imr - Interrupt mask register of MADC
 * @isr - Interrupt status register of MADC
 */
struct twl4030_madc_data {
	struct device *dev;
	struct mutex lock;	/* mutex protecting this data structure */
	struct twl4030_madc_request requests[TWL4030_MADC_NUM_METHODS];
	int imr;
	int isr;
};

static struct twl4030_madc_data *twl4030_madc;

struct twl4030_prescale_divider_ratios {
	s16 numerator;
	s16 denominator;
};

static const struct twl4030_prescale_divider_ratios
twl4030_divider_ratios[16] = {
	{1, 1},		/* CHANNEL 0 No Prescaler */
	{1, 1},		/* CHANNEL 1 No Prescaler */
	{6, 10},	/* CHANNEL 2 */
	{6, 10},	/* CHANNEL 3 */
	{6, 10},	/* CHANNEL 4 */
	{6, 10},	/* CHANNEL 5 */
	{6, 10},	/* CHANNEL 6 */
	{6, 10},	/* CHANNEL 7 */
	{3, 14},	/* CHANNEL 8 */
	{1, 3},		/* CHANNEL 9 */
	{1, 1},		/* CHANNEL 10 No Prescaler */
	{15, 100},	/* CHANNEL 11 */
	{1, 4},		/* CHANNEL 12 */
	{1, 1},		/* CHANNEL 13 Reserved channels */
	{1, 1},		/* CHANNEL 14 Reseved channels */
	{5, 11},	/* CHANNEL 15 */
};


/*
 * Conversion table from -3 to 55 degree Celcius
 */
static int therm_tbl[] = {
30800,	29500,	28300,	27100,
26000,	24900,	23900,	22900,	22000,	21100,	20300,	19400,	18700,	17900,
17200,	16500,	15900,	15300,	14700,	14100,	13600,	13100,	12600,	12100,
11600,	11200,	10800,	10400,	10000,	9630,	9280,	8950,	8620,	8310,
8020,	7730,	7460,	7200,	6950,	6710,	6470,	6250,	6040,	5830,
5640,	5450,	5260,	5090,	4920,	4760,	4600,	4450,	4310,	4170,
4040,	3910,	3790,	3670,	3550
};

/*
 * Structure containing the registers
 * of different conversion methods supported by MADC.
 * Hardware or RT real time conversion request initiated by external host
 * processor for RT Signal conversions.
 * External host processors can also request for non RT conversions
 * SW1 and SW2 software conversions also called asynchronous or GPC request.
 */
static
const struct twl4030_madc_conversion_method twl4030_conversion_methods[] = {
	[TWL4030_MADC_RT] = {
			     .sel = TWL4030_MADC_RTSELECT_LSB,
			     .avg = TWL4030_MADC_RTAVERAGE_LSB,
			     .rbase = TWL4030_MADC_RTCH0_LSB,
			     },
	[TWL4030_MADC_SW1] = {
			      .sel = TWL4030_MADC_SW1SELECT_LSB,
			      .avg = TWL4030_MADC_SW1AVERAGE_LSB,
			      .rbase = TWL4030_MADC_GPCH0_LSB,
			      .ctrl = TWL4030_MADC_CTRL_SW1,
			      },
	[TWL4030_MADC_SW2] = {
			      .sel = TWL4030_MADC_SW2SELECT_LSB,
			      .avg = TWL4030_MADC_SW2AVERAGE_LSB,
			      .rbase = TWL4030_MADC_GPCH0_LSB,
			      .ctrl = TWL4030_MADC_CTRL_SW2,
			      },
};

/*
 * Function to read a particular channel value.
 * @madc - pointer to struct twl4030_madc_data
 * @reg - lsb of ADC Channel
 * If the i2c read fails it returns an error else returns 0.
 */
static int twl4030_madc_channel_raw_read(struct twl4030_madc_data *madc, u8 reg)
{
	u8 msb, lsb;
	int ret;
	/*
	 * For each ADC channel, we have MSB and LSB register pair. MSB address
	 * is always LSB address+1. reg parameter is the address of LSB register
	 */
	ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &msb, reg + 1);
	if (ret) {
		dev_err(madc->dev, "unable to read MSB register 0x%X\n",
			reg + 1);
		return ret;
	}
	ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &lsb, reg);
	if (ret) {
		dev_err(madc->dev, "unable to read LSB register 0x%X\n", reg);
		return ret;
	}

	return (int)(((msb << 8) | lsb) >> 6);
}

/*
 * Return battery temperature
 * Or < 0 on failure.
 */
static int twl4030battery_temperature(int raw_volt)
{
	u8 val;
	int temp, curr, volt, res, ret;

	volt = (raw_volt * TEMP_STEP_SIZE) / TEMP_PSR_R;
	/* Getting and calculating the supply current in micro ampers */
	ret = twl_i2c_read_u8(TWL4030_MODULE_MAIN_CHARGE, &val,
		REG_BCICTL2);
	if (ret < 0)
		return ret;
	curr = ((val & TWL4030_BCI_ITHEN) + 1) * 10;
	/* Getting and calculating the thermistor resistance in ohms */
	res = volt * 1000 / curr;
	/* calculating temperature */
	for (temp = 58; temp >= 0; temp--) {
		int actual = therm_tbl[temp];

		if ((actual - res) >= 0)
			break;
	}

	return temp + 1;
}

static int twl4030battery_current(int raw_volt)
{
	int ret;
	u8 val;

	ret = twl_i2c_read_u8(TWL4030_MODULE_MAIN_CHARGE, &val,
		TWL4030_BCI_BCICTL1);
	if (ret)
		return ret;
	if (val & TWL4030_BCI_CGAIN) /* slope of 0.44 mV/mA */
		return (raw_volt * CURR_STEP_SIZE) / CURR_PSR_R1;
	else /* slope of 0.88 mV/mA */
		return (raw_volt * CURR_STEP_SIZE) / CURR_PSR_R2;
}
/*
 * Function to read channel values
 * @madc - pointer to twl4030_madc_data struct
 * @reg_base - Base address of the first channel
 * @Channels - 16 bit bitmap. If the bit is set, channel value is read
 * @buf - The channel values are stored here. if read fails error
 * value is stored
 * Returns the number of successfully read channels.
 */
static int twl4030_madc_read_channels(struct twl4030_madc_data *madc,
				      u8 reg_base, unsigned
						long channels, int *buf)
{
	int count = 0, count_req = 0, i;
	u8 reg;

	for_each_set_bit(i, &channels, TWL4030_MADC_MAX_CHANNELS) {
		reg = reg_base + 2 * i;
		buf[i] = twl4030_madc_channel_raw_read(madc, reg);
		if (buf[i] < 0) {
			dev_err(madc->dev,
				"Unable to read register 0x%X\n", reg);
			count_req++;
			continue;
		}
		switch (i) {
		case 10:
			buf[i] = twl4030battery_current(buf[i]);
			if (buf[i] < 0) {
				dev_err(madc->dev, "err reading current\n");
				count_req++;
			} else {
				count++;
				buf[i] = buf[i] - 750;
			}
			break;
		case 1:
			buf[i] = twl4030battery_temperature(buf[i]);
			if (buf[i] < 0) {
				dev_err(madc->dev, "err reading temperature\n");
				count_req++;
			} else {
				buf[i] -= 3;
				count++;
			}
			break;
		default:
			count++;
			/* Analog Input (V) = conv_result * step_size / R
			 * conv_result = decimal value of 10-bit conversion
			 *		 result
			 * step size = 1.5 / (2 ^ 10 -1)
			 * R = Prescaler ratio for input channels.
			 * Result given in mV hence multiplied by 1000.
			 */
			buf[i] = (buf[i] * 3 * 1000 *
				 twl4030_divider_ratios[i].denominator)
				/ (2 * 1023 *
				twl4030_divider_ratios[i].numerator);
		}
	}
	if (count_req)
		dev_err(madc->dev, "%d channel conversion failed\n", count_req);

	return count;
}

/*
 * Enables irq.
 * @madc - pointer to twl4030_madc_data struct
 * @id - irq number to be enabled
 * can take one of TWL4030_MADC_RT, TWL4030_MADC_SW1, TWL4030_MADC_SW2
 * corresponding to RT, SW1, SW2 conversion requests.
 * If the i2c read fails it returns an error else returns 0.
 */
static int twl4030_madc_enable_irq(struct twl4030_madc_data *madc, u8 id)
{
	u8 val;
	int ret;

	ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &val, madc->imr);
	if (ret) {
		dev_err(madc->dev, "unable to read imr register 0x%X\n",
			madc->imr);
		return ret;
	}
	val &= ~(1 << id);
	ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, val, madc->imr);
	if (ret) {
		dev_err(madc->dev,
			"unable to write imr register 0x%X\n", madc->imr);
		return ret;

	}

	return 0;
}

/*
 * Disables irq.
 * @madc - pointer to twl4030_madc_data struct
 * @id - irq number to be disabled
 * can take one of TWL4030_MADC_RT, TWL4030_MADC_SW1, TWL4030_MADC_SW2
 * corresponding to RT, SW1, SW2 conversion requests.
 * Returns error if i2c read/write fails.
 */
static int twl4030_madc_disable_irq(struct twl4030_madc_data *madc, u8 id)
{
	u8 val;
	int ret;

	ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &val, madc->imr);
	if (ret) {
		dev_err(madc->dev, "unable to read imr register 0x%X\n",
			madc->imr);
		return ret;
	}
	val |= (1 << id);
	ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, val, madc->imr);
	if (ret) {
		dev_err(madc->dev,
			"unable to write imr register 0x%X\n", madc->imr);
		return ret;
	}

	return 0;
}

static irqreturn_t twl4030_madc_threaded_irq_handler(int irq, void *_madc)
{
	struct twl4030_madc_data *madc = _madc;
	const struct twl4030_madc_conversion_method *method;
	u8 isr_val, imr_val;
	int i, len, ret;
	struct twl4030_madc_request *r;

	mutex_lock(&madc->lock);
	ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &isr_val, madc->isr);
	if (ret) {
		dev_err(madc->dev, "unable to read isr register 0x%X\n",
			madc->isr);
		goto err_i2c;
	}
	ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &imr_val, madc->imr);
	if (ret) {
		dev_err(madc->dev, "unable to read imr register 0x%X\n",
			madc->imr);
		goto err_i2c;
	}
	isr_val &= ~imr_val;
	for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) {
		if (!(isr_val & (1 << i)))
			continue;
		ret = twl4030_madc_disable_irq(madc, i);
		if (ret < 0)
			dev_dbg(madc->dev, "Disable interrupt failed%d\n", i);
		madc->requests[i].result_pending = 1;
	}
	for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) {
		r = &madc->requests[i];
		/* No pending results for this method, move to next one */
		if (!r->result_pending)
			continue;
		method = &twl4030_conversion_methods[r->method];
		/* Read results */
		len = twl4030_madc_read_channels(madc, method->rbase,
						 r->channels, r->rbuf);
		/* Return results to caller */
		if (r->func_cb != NULL) {
			r->func_cb(len, r->channels, r->rbuf);
			r->func_cb = NULL;
		}
		/* Free request */
		r->result_pending = 0;
		r->active = 0;
	}
	mutex_unlock(&madc->lock);

	return IRQ_HANDLED;

err_i2c:
	/*
	 * In case of error check whichever request is active
	 * and service the same.
	 */
	for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) {
		r = &madc->requests[i];
		if (r->active == 0)
			continue;
		method = &twl4030_conversion_methods[r->method];
		/* Read results */
		len = twl4030_madc_read_channels(madc, method->rbase,
						 r->channels, r->rbuf);
		/* Return results to caller */
		if (r->func_cb != NULL) {
			r->func_cb(len, r->channels, r->rbuf);
			r->func_cb = NULL;
		}
		/* Free request */
		r->result_pending = 0;
		r->active = 0;
	}
	mutex_unlock(&madc->lock);

	return IRQ_HANDLED;
}

static int twl4030_madc_set_irq(struct twl4030_madc_data *madc,
				struct twl4030_madc_request *req)
{
	struct twl4030_madc_request *p;
	int ret;

	p = &madc->requests[req->method];
	memcpy(p, req, sizeof(*req));
	ret = twl4030_madc_enable_irq(madc, req->method);
	if (ret < 0) {
		dev_err(madc->dev, "enable irq failed!!\n");
		return ret;
	}

	return 0;
}

/*
 * Function which enables the madc conversion
 * by writing to the control register.
 * @madc - pointer to twl4030_madc_data struct
 * @conv_method - can be TWL4030_MADC_RT, TWL4030_MADC_SW2, TWL4030_MADC_SW1
 * corresponding to RT SW1 or SW2 conversion methods.
 * Returns 0 if succeeds else a negative error value
 */
static int twl4030_madc_start_conversion(struct twl4030_madc_data *madc,
					 int conv_method)
{
	const struct twl4030_madc_conversion_method *method;
	int ret = 0;
	method = &twl4030_conversion_methods[conv_method];
	switch (conv_method) {
	case TWL4030_MADC_SW1:
	case TWL4030_MADC_SW2:
		ret = twl_i2c_write_u8(TWL4030_MODULE_MADC,
				       TWL4030_MADC_SW_START, method->ctrl);
		if (ret) {
			dev_err(madc->dev,
				"unable to write ctrl register 0x%X\n",
				method->ctrl);
			return ret;
		}
		break;
	default:
		break;
	}

	return 0;
}

/*
 * Function that waits for conversion to be ready
 * @madc - pointer to twl4030_madc_data struct
 * @timeout_ms - timeout value in milliseconds
 * @status_reg - ctrl register
 * returns 0 if succeeds else a negative error value
 */
static int twl4030_madc_wait_conversion_ready(struct twl4030_madc_data *madc,
					      unsigned int timeout_ms,
					      u8 status_reg)
{
	unsigned long timeout;
	int ret;

	timeout = jiffies + msecs_to_jiffies(timeout_ms);
	do {
		u8 reg;

		ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &reg, status_reg);
		if (ret) {
			dev_err(madc->dev,
				"unable to read status register 0x%X\n",
				status_reg);
			return ret;
		}
		if (!(reg & TWL4030_MADC_BUSY) && (reg & TWL4030_MADC_EOC_SW))
			return 0;
		usleep_range(500, 2000);
	} while (!time_after(jiffies, timeout));
	dev_err(madc->dev, "conversion timeout!\n");

	return -EAGAIN;
}

/*
 * An exported function which can be called from other kernel drivers.
 * @req twl4030_madc_request structure
 * req->rbuf will be filled with read values of channels based on the
 * channel index. If a particular channel reading fails there will
 * be a negative error value in the corresponding array element.
 * returns 0 if succeeds else error value
 */
int twl4030_madc_conversion(struct twl4030_madc_request *req)
{
	const struct twl4030_madc_conversion_method *method;
	u8 ch_msb, ch_lsb;
	int ret;

	if (!req || !twl4030_madc)
		return -EINVAL;

	mutex_lock(&twl4030_madc->lock);
	if (req->method < TWL4030_MADC_RT || req->method > TWL4030_MADC_SW2) {
		ret = -EINVAL;
		goto out;
	}
	/* Do we have a conversion request ongoing */
	if (twl4030_madc->requests[req->method].active) {
		ret = -EBUSY;
		goto out;
	}
	ch_msb = (req->channels >> 8) & 0xff;
	ch_lsb = req->channels & 0xff;
	method = &twl4030_conversion_methods[req->method];
	/* Select channels to be converted */
	ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, ch_msb, method->sel + 1);
	if (ret) {
		dev_err(twl4030_madc->dev,
			"unable to write sel register 0x%X\n", method->sel + 1);
		goto out;
	}
	ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, ch_lsb, method->sel);
	if (ret) {
		dev_err(twl4030_madc->dev,
			"unable to write sel register 0x%X\n", method->sel + 1);
		goto out;
	}
	/* Select averaging for all channels if do_avg is set */
	if (req->do_avg) {
		ret = twl_i2c_write_u8(TWL4030_MODULE_MADC,
				       ch_msb, method->avg + 1);
		if (ret) {
			dev_err(twl4030_madc->dev,
				"unable to write avg register 0x%X\n",
				method->avg + 1);
			goto out;
		}
		ret = twl_i2c_write_u8(TWL4030_MODULE_MADC,
				       ch_lsb, method->avg);
		if (ret) {
			dev_err(twl4030_madc->dev,
				"unable to write sel reg 0x%X\n",
				method->sel + 1);
			goto out;
		}
	}
	if (req->type == TWL4030_MADC_IRQ_ONESHOT && req->func_cb != NULL) {
		ret = twl4030_madc_set_irq(twl4030_madc, req);
		if (ret < 0)
			goto out;
		ret = twl4030_madc_start_conversion(twl4030_madc, req->method);
		if (ret < 0)
			goto out;
		twl4030_madc->requests[req->method].active = 1;
		ret = 0;
		goto out;
	}
	/* With RT method we should not be here anymore */
	if (req->method == TWL4030_MADC_RT) {
		ret = -EINVAL;
		goto out;
	}
	ret = twl4030_madc_start_conversion(twl4030_madc, req->method);
	if (ret < 0)
		goto out;
	twl4030_madc->requests[req->method].active = 1;
	/* Wait until conversion is ready (ctrl register returns EOC) */
	ret = twl4030_madc_wait_conversion_ready(twl4030_madc, 5, method->ctrl);
	if (ret) {
		twl4030_madc->requests[req->method].active = 0;
		goto out;
	}
	ret = twl4030_madc_read_channels(twl4030_madc, method->rbase,
					 req->channels, req->rbuf);
	twl4030_madc->requests[req->method].active = 0;

out:
	mutex_unlock(&twl4030_madc->lock);

	return ret;
}
EXPORT_SYMBOL_GPL(twl4030_madc_conversion);

/*
 * Return channel value
 * Or < 0 on failure.
 */
int twl4030_get_madc_conversion(int channel_no)
{
	struct twl4030_madc_request req;
	int temp = 0;
	int ret;

	req.channels = (1 << channel_no);
	req.method = TWL4030_MADC_SW2;
	req.active = 0;
	req.func_cb = NULL;
	ret = twl4030_madc_conversion(&req);
	if (ret < 0)
		return ret;
	if (req.rbuf[channel_no] > 0)
		temp = req.rbuf[channel_no];

	return temp;
}
EXPORT_SYMBOL_GPL(twl4030_get_madc_conversion);

/*
 * Function to enable or disable bias current for
 * main battery type reading or temperature sensing
 * @madc - pointer to twl4030_madc_data struct
 * @chan - can be one of the two values
 * TWL4030_BCI_ITHEN - Enables bias current for main battery type reading
 * TWL4030_BCI_TYPEN - Enables bias current for main battery temperature
 * sensing
 * @on - enable or disable chan.
 */
static int twl4030_madc_set_current_generator(struct twl4030_madc_data *madc,
					      int chan, int on)
{
	int ret;
	u8 regval;

	ret = twl_i2c_read_u8(TWL4030_MODULE_MAIN_CHARGE,
			      &regval, TWL4030_BCI_BCICTL1);
	if (ret) {
		dev_err(madc->dev, "unable to read BCICTL1 reg 0x%X",
			TWL4030_BCI_BCICTL1);
		return ret;
	}
	if (on)
		regval |= chan ? TWL4030_BCI_ITHEN : TWL4030_BCI_TYPEN;
	else
		regval &= chan ? ~TWL4030_BCI_ITHEN : ~TWL4030_BCI_TYPEN;
	ret = twl_i2c_write_u8(TWL4030_MODULE_MAIN_CHARGE,
			       regval, TWL4030_BCI_BCICTL1);
	if (ret) {
		dev_err(madc->dev, "unable to write BCICTL1 reg 0x%X\n",
			TWL4030_BCI_BCICTL1);
		return ret;
	}

	return 0;
}

/*
 * Function that sets MADC software power on bit to enable MADC
 * @madc - pointer to twl4030_madc_data struct
 * @on - Enable or disable MADC software powen on bit.
 * returns error if i2c read/write fails else 0
 */
static int twl4030_madc_set_power(struct twl4030_madc_data *madc, int on)
{
	u8 regval;
	int ret;

	ret = twl_i2c_read_u8(TWL4030_MODULE_MAIN_CHARGE,
			      &regval, TWL4030_MADC_CTRL1);
	if (ret) {
		dev_err(madc->dev, "unable to read madc ctrl1 reg 0x%X\n",
			TWL4030_MADC_CTRL1);
		return ret;
	}
	if (on)
		regval |= TWL4030_MADC_MADCON;
	else
		regval &= ~TWL4030_MADC_MADCON;
	ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, regval, TWL4030_MADC_CTRL1);
	if (ret) {
		dev_err(madc->dev, "unable to write madc ctrl1 reg 0x%X\n",
			TWL4030_MADC_CTRL1);
		return ret;
	}

	return 0;
}

/*
 * Initialize MADC and request for threaded irq
 */
static int __devinit twl4030_madc_probe(struct platform_device *pdev)
{
	struct twl4030_madc_data *madc;
	struct twl4030_madc_platform_data *pdata = pdev->dev.platform_data;
	int ret;
	u8 regval;

	if (!pdata) {
		dev_err(&pdev->dev, "platform_data not available\n");
		return -EINVAL;
	}
	madc = kzalloc(sizeof(*madc), GFP_KERNEL);
	if (!madc)
		return -ENOMEM;

	madc->dev = &pdev->dev;

	/*
	 * Phoenix provides 2 interrupt lines. The first one is connected to
	 * the OMAP. The other one can be connected to the other processor such
	 * as modem. Hence two separate ISR and IMR registers.
	 */
	madc->imr = (pdata->irq_line == 1) ?
	    TWL4030_MADC_IMR1 : TWL4030_MADC_IMR2;
	madc->isr = (pdata->irq_line == 1) ?
	    TWL4030_MADC_ISR1 : TWL4030_MADC_ISR2;
	ret = twl4030_madc_set_power(madc, 1);
	if (ret < 0)
		goto err_power;
	ret = twl4030_madc_set_current_generator(madc, 0, 1);
	if (ret < 0)
		goto err_current_generator;

	ret = twl_i2c_read_u8(TWL4030_MODULE_MAIN_CHARGE,
			      &regval, TWL4030_BCI_BCICTL1);
	if (ret) {
		dev_err(&pdev->dev, "unable to read reg BCI CTL1 0x%X\n",
			TWL4030_BCI_BCICTL1);
		goto err_i2c;
	}
	regval |= TWL4030_BCI_MESBAT;
	ret = twl_i2c_write_u8(TWL4030_MODULE_MAIN_CHARGE,
			       regval, TWL4030_BCI_BCICTL1);
	if (ret) {
		dev_err(&pdev->dev, "unable to write reg BCI Ctl1 0x%X\n",
			TWL4030_BCI_BCICTL1);
		goto err_i2c;
	}

	/* Check that MADC clock is on */
	ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, &regval, TWL4030_REG_GPBR1);
	if (ret) {
		dev_err(&pdev->dev, "unable to read reg GPBR1 0x%X\n",
				TWL4030_REG_GPBR1);
		goto err_i2c;
	}

	/* If MADC clk is not on, turn it on */
	if (!(regval & TWL4030_GPBR1_MADC_HFCLK_EN)) {
		dev_info(&pdev->dev, "clk disabled, enabling\n");
		regval |= TWL4030_GPBR1_MADC_HFCLK_EN;
		ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, regval,
				       TWL4030_REG_GPBR1);
		if (ret) {
			dev_err(&pdev->dev, "unable to write reg GPBR1 0x%X\n",
					TWL4030_REG_GPBR1);
			goto err_i2c;
		}
	}

	platform_set_drvdata(pdev, madc);
	mutex_init(&madc->lock);
	ret = request_threaded_irq(platform_get_irq(pdev, 0), NULL,
				   twl4030_madc_threaded_irq_handler,
				   IRQF_TRIGGER_RISING, "twl4030_madc", madc);
	if (ret) {
		dev_dbg(&pdev->dev, "could not request irq\n");
		goto err_irq;
	}
	twl4030_madc = madc;
	return 0;
err_irq:
	platform_set_drvdata(pdev, NULL);
err_i2c:
	twl4030_madc_set_current_generator(madc, 0, 0);
err_current_generator:
	twl4030_madc_set_power(madc, 0);
err_power:
	kfree(madc);

	return ret;
}

static int __devexit twl4030_madc_remove(struct platform_device *pdev)
{
	struct twl4030_madc_data *madc = platform_get_drvdata(pdev);

	free_irq(platform_get_irq(pdev, 0), madc);
	platform_set_drvdata(pdev, NULL);
	twl4030_madc_set_current_generator(madc, 0, 0);
	twl4030_madc_set_power(madc, 0);
	kfree(madc);

	return 0;
}

static struct platform_driver twl4030_madc_driver = {
	.probe = twl4030_madc_probe,
	.remove = __exit_p(twl4030_madc_remove),
	.driver = {
		   .name = "twl4030_madc",
		   .owner = THIS_MODULE,
		   },
};

module_platform_driver(twl4030_madc_driver);

MODULE_DESCRIPTION("TWL4030 ADC driver");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("J Keerthy");
MODULE_ALIAS("platform:twl4030_madc");