xref: /linux/drivers/iio/adc/exynos_adc.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  exynos_adc.c - Support for ADC in EXYNOS SoCs
4  *
5  *  8 ~ 10 channel, 10/12-bit ADC
6  *
7  *  Copyright (C) 2013 Naveen Krishna Chatradhi <ch.naveen@samsung.com>
8  */
9 
10 #include <linux/compiler.h>
11 #include <linux/module.h>
12 #include <linux/platform_device.h>
13 #include <linux/interrupt.h>
14 #include <linux/delay.h>
15 #include <linux/errno.h>
16 #include <linux/kernel.h>
17 #include <linux/slab.h>
18 #include <linux/io.h>
19 #include <linux/clk.h>
20 #include <linux/completion.h>
21 #include <linux/of.h>
22 #include <linux/of_irq.h>
23 #include <linux/regulator/consumer.h>
24 #include <linux/of_platform.h>
25 #include <linux/err.h>
26 #include <linux/input.h>
27 
28 #include <linux/iio/iio.h>
29 #include <linux/iio/machine.h>
30 #include <linux/iio/driver.h>
31 #include <linux/mfd/syscon.h>
32 #include <linux/regmap.h>
33 
34 #include <linux/platform_data/touchscreen-s3c2410.h>
35 
36 /* S3C/EXYNOS4412/5250 ADC_V1 registers definitions */
37 #define ADC_V1_CON(x)		((x) + 0x00)
38 #define ADC_V1_TSC(x)		((x) + 0x04)
39 #define ADC_V1_DLY(x)		((x) + 0x08)
40 #define ADC_V1_DATX(x)		((x) + 0x0C)
41 #define ADC_V1_DATY(x)		((x) + 0x10)
42 #define ADC_V1_UPDN(x)		((x) + 0x14)
43 #define ADC_V1_INTCLR(x)	((x) + 0x18)
44 #define ADC_V1_MUX(x)		((x) + 0x1c)
45 #define ADC_V1_CLRINTPNDNUP(x)	((x) + 0x20)
46 
47 /* S3C2410 ADC registers definitions */
48 #define ADC_S3C2410_MUX(x)	((x) + 0x18)
49 
50 /* Future ADC_V2 registers definitions */
51 #define ADC_V2_CON1(x)		((x) + 0x00)
52 #define ADC_V2_CON2(x)		((x) + 0x04)
53 #define ADC_V2_STAT(x)		((x) + 0x08)
54 #define ADC_V2_INT_EN(x)	((x) + 0x10)
55 #define ADC_V2_INT_ST(x)	((x) + 0x14)
56 #define ADC_V2_VER(x)		((x) + 0x20)
57 
58 /* Bit definitions for ADC_V1 */
59 #define ADC_V1_CON_RES		(1u << 16)
60 #define ADC_V1_CON_PRSCEN	(1u << 14)
61 #define ADC_V1_CON_PRSCLV(x)	(((x) & 0xFF) << 6)
62 #define ADC_V1_CON_STANDBY	(1u << 2)
63 
64 /* Bit definitions for S3C2410 ADC */
65 #define ADC_S3C2410_CON_SELMUX(x) (((x) & 7) << 3)
66 #define ADC_S3C2410_DATX_MASK	0x3FF
67 #define ADC_S3C2416_CON_RES_SEL	(1u << 3)
68 
69 /* touch screen always uses channel 0 */
70 #define ADC_S3C2410_MUX_TS	0
71 
72 /* ADCTSC Register Bits */
73 #define ADC_S3C2443_TSC_UD_SEN		(1u << 8)
74 #define ADC_S3C2410_TSC_YM_SEN		(1u << 7)
75 #define ADC_S3C2410_TSC_YP_SEN		(1u << 6)
76 #define ADC_S3C2410_TSC_XM_SEN		(1u << 5)
77 #define ADC_S3C2410_TSC_XP_SEN		(1u << 4)
78 #define ADC_S3C2410_TSC_PULL_UP_DISABLE	(1u << 3)
79 #define ADC_S3C2410_TSC_AUTO_PST	(1u << 2)
80 #define ADC_S3C2410_TSC_XY_PST(x)	(((x) & 0x3) << 0)
81 
82 #define ADC_TSC_WAIT4INT (ADC_S3C2410_TSC_YM_SEN | \
83 			 ADC_S3C2410_TSC_YP_SEN | \
84 			 ADC_S3C2410_TSC_XP_SEN | \
85 			 ADC_S3C2410_TSC_XY_PST(3))
86 
87 #define ADC_TSC_AUTOPST	(ADC_S3C2410_TSC_YM_SEN | \
88 			 ADC_S3C2410_TSC_YP_SEN | \
89 			 ADC_S3C2410_TSC_XP_SEN | \
90 			 ADC_S3C2410_TSC_AUTO_PST | \
91 			 ADC_S3C2410_TSC_XY_PST(0))
92 
93 /* Bit definitions for ADC_V2 */
94 #define ADC_V2_CON1_SOFT_RESET	(1u << 2)
95 
96 #define ADC_V2_CON2_OSEL	(1u << 10)
97 #define ADC_V2_CON2_ESEL	(1u << 9)
98 #define ADC_V2_CON2_HIGHF	(1u << 8)
99 #define ADC_V2_CON2_C_TIME(x)	(((x) & 7) << 4)
100 #define ADC_V2_CON2_ACH_SEL(x)	(((x) & 0xF) << 0)
101 #define ADC_V2_CON2_ACH_MASK	0xF
102 
103 #define MAX_ADC_V2_CHANNELS		10
104 #define MAX_ADC_V1_CHANNELS		8
105 #define MAX_EXYNOS3250_ADC_CHANNELS	2
106 #define MAX_EXYNOS4212_ADC_CHANNELS	4
107 #define MAX_S5PV210_ADC_CHANNELS	10
108 
109 /* Bit definitions common for ADC_V1 and ADC_V2 */
110 #define ADC_CON_EN_START	(1u << 0)
111 #define ADC_CON_EN_START_MASK	(0x3 << 0)
112 #define ADC_DATX_PRESSED	(1u << 15)
113 #define ADC_DATX_MASK		0xFFF
114 #define ADC_DATY_MASK		0xFFF
115 
116 #define EXYNOS_ADC_TIMEOUT	(msecs_to_jiffies(100))
117 
118 #define EXYNOS_ADCV1_PHY_OFFSET	0x0718
119 #define EXYNOS_ADCV2_PHY_OFFSET	0x0720
120 
121 struct exynos_adc {
122 	struct exynos_adc_data	*data;
123 	struct device		*dev;
124 	struct input_dev	*input;
125 	void __iomem		*regs;
126 	struct regmap		*pmu_map;
127 	struct clk		*clk;
128 	struct clk		*sclk;
129 	unsigned int		irq;
130 	unsigned int		tsirq;
131 	unsigned int		delay;
132 	struct regulator	*vdd;
133 
134 	struct completion	completion;
135 
136 	u32			value;
137 	unsigned int            version;
138 
139 	bool			ts_enabled;
140 
141 	bool			read_ts;
142 	u32			ts_x;
143 	u32			ts_y;
144 
145 	/*
146 	 * Lock to protect from potential concurrent access to the
147 	 * completion callback during a manual conversion. For this driver
148 	 * a wait-callback is used to wait for the conversion result,
149 	 * so in the meantime no other read request (or conversion start)
150 	 * must be performed, otherwise it would interfere with the
151 	 * current conversion result.
152 	 */
153 	struct mutex		lock;
154 };
155 
156 struct exynos_adc_data {
157 	int num_channels;
158 	bool needs_sclk;
159 	bool needs_adc_phy;
160 	int phy_offset;
161 	u32 mask;
162 
163 	void (*init_hw)(struct exynos_adc *info);
164 	void (*exit_hw)(struct exynos_adc *info);
165 	void (*clear_irq)(struct exynos_adc *info);
166 	void (*start_conv)(struct exynos_adc *info, unsigned long addr);
167 };
168 
169 static void exynos_adc_unprepare_clk(struct exynos_adc *info)
170 {
171 	if (info->data->needs_sclk)
172 		clk_unprepare(info->sclk);
173 	clk_unprepare(info->clk);
174 }
175 
176 static int exynos_adc_prepare_clk(struct exynos_adc *info)
177 {
178 	int ret;
179 
180 	ret = clk_prepare(info->clk);
181 	if (ret) {
182 		dev_err(info->dev, "failed preparing adc clock: %d\n", ret);
183 		return ret;
184 	}
185 
186 	if (info->data->needs_sclk) {
187 		ret = clk_prepare(info->sclk);
188 		if (ret) {
189 			clk_unprepare(info->clk);
190 			dev_err(info->dev,
191 				"failed preparing sclk_adc clock: %d\n", ret);
192 			return ret;
193 		}
194 	}
195 
196 	return 0;
197 }
198 
199 static void exynos_adc_disable_clk(struct exynos_adc *info)
200 {
201 	if (info->data->needs_sclk)
202 		clk_disable(info->sclk);
203 	clk_disable(info->clk);
204 }
205 
206 static int exynos_adc_enable_clk(struct exynos_adc *info)
207 {
208 	int ret;
209 
210 	ret = clk_enable(info->clk);
211 	if (ret) {
212 		dev_err(info->dev, "failed enabling adc clock: %d\n", ret);
213 		return ret;
214 	}
215 
216 	if (info->data->needs_sclk) {
217 		ret = clk_enable(info->sclk);
218 		if (ret) {
219 			clk_disable(info->clk);
220 			dev_err(info->dev,
221 				"failed enabling sclk_adc clock: %d\n", ret);
222 			return ret;
223 		}
224 	}
225 
226 	return 0;
227 }
228 
229 static void exynos_adc_v1_init_hw(struct exynos_adc *info)
230 {
231 	u32 con1;
232 
233 	if (info->data->needs_adc_phy)
234 		regmap_write(info->pmu_map, info->data->phy_offset, 1);
235 
236 	/* set default prescaler values and Enable prescaler */
237 	con1 =  ADC_V1_CON_PRSCLV(49) | ADC_V1_CON_PRSCEN;
238 
239 	/* Enable 12-bit ADC resolution */
240 	con1 |= ADC_V1_CON_RES;
241 	writel(con1, ADC_V1_CON(info->regs));
242 
243 	/* set touchscreen delay */
244 	writel(info->delay, ADC_V1_DLY(info->regs));
245 }
246 
247 static void exynos_adc_v1_exit_hw(struct exynos_adc *info)
248 {
249 	u32 con;
250 
251 	if (info->data->needs_adc_phy)
252 		regmap_write(info->pmu_map, info->data->phy_offset, 0);
253 
254 	con = readl(ADC_V1_CON(info->regs));
255 	con |= ADC_V1_CON_STANDBY;
256 	writel(con, ADC_V1_CON(info->regs));
257 }
258 
259 static void exynos_adc_v1_clear_irq(struct exynos_adc *info)
260 {
261 	writel(1, ADC_V1_INTCLR(info->regs));
262 }
263 
264 static void exynos_adc_v1_start_conv(struct exynos_adc *info,
265 				     unsigned long addr)
266 {
267 	u32 con1;
268 
269 	writel(addr, ADC_V1_MUX(info->regs));
270 
271 	con1 = readl(ADC_V1_CON(info->regs));
272 	writel(con1 | ADC_CON_EN_START, ADC_V1_CON(info->regs));
273 }
274 
275 /* Exynos4212 and 4412 is like ADCv1 but with four channels only */
276 static const struct exynos_adc_data exynos4212_adc_data = {
277 	.num_channels	= MAX_EXYNOS4212_ADC_CHANNELS,
278 	.mask		= ADC_DATX_MASK,	/* 12 bit ADC resolution */
279 	.needs_adc_phy	= true,
280 	.phy_offset	= EXYNOS_ADCV1_PHY_OFFSET,
281 
282 	.init_hw	= exynos_adc_v1_init_hw,
283 	.exit_hw	= exynos_adc_v1_exit_hw,
284 	.clear_irq	= exynos_adc_v1_clear_irq,
285 	.start_conv	= exynos_adc_v1_start_conv,
286 };
287 
288 static const struct exynos_adc_data exynos_adc_v1_data = {
289 	.num_channels	= MAX_ADC_V1_CHANNELS,
290 	.mask		= ADC_DATX_MASK,	/* 12 bit ADC resolution */
291 	.needs_adc_phy	= true,
292 	.phy_offset	= EXYNOS_ADCV1_PHY_OFFSET,
293 
294 	.init_hw	= exynos_adc_v1_init_hw,
295 	.exit_hw	= exynos_adc_v1_exit_hw,
296 	.clear_irq	= exynos_adc_v1_clear_irq,
297 	.start_conv	= exynos_adc_v1_start_conv,
298 };
299 
300 static const struct exynos_adc_data exynos_adc_s5pv210_data = {
301 	.num_channels	= MAX_S5PV210_ADC_CHANNELS,
302 	.mask		= ADC_DATX_MASK,	/* 12 bit ADC resolution */
303 
304 	.init_hw	= exynos_adc_v1_init_hw,
305 	.exit_hw	= exynos_adc_v1_exit_hw,
306 	.clear_irq	= exynos_adc_v1_clear_irq,
307 	.start_conv	= exynos_adc_v1_start_conv,
308 };
309 
310 static void exynos_adc_s3c2416_start_conv(struct exynos_adc *info,
311 					  unsigned long addr)
312 {
313 	u32 con1;
314 
315 	/* Enable 12 bit ADC resolution */
316 	con1 = readl(ADC_V1_CON(info->regs));
317 	con1 |= ADC_S3C2416_CON_RES_SEL;
318 	writel(con1, ADC_V1_CON(info->regs));
319 
320 	/* Select channel for S3C2416 */
321 	writel(addr, ADC_S3C2410_MUX(info->regs));
322 
323 	con1 = readl(ADC_V1_CON(info->regs));
324 	writel(con1 | ADC_CON_EN_START, ADC_V1_CON(info->regs));
325 }
326 
327 static struct exynos_adc_data const exynos_adc_s3c2416_data = {
328 	.num_channels	= MAX_ADC_V1_CHANNELS,
329 	.mask		= ADC_DATX_MASK,	/* 12 bit ADC resolution */
330 
331 	.init_hw	= exynos_adc_v1_init_hw,
332 	.exit_hw	= exynos_adc_v1_exit_hw,
333 	.start_conv	= exynos_adc_s3c2416_start_conv,
334 };
335 
336 static void exynos_adc_s3c2443_start_conv(struct exynos_adc *info,
337 					  unsigned long addr)
338 {
339 	u32 con1;
340 
341 	/* Select channel for S3C2433 */
342 	writel(addr, ADC_S3C2410_MUX(info->regs));
343 
344 	con1 = readl(ADC_V1_CON(info->regs));
345 	writel(con1 | ADC_CON_EN_START, ADC_V1_CON(info->regs));
346 }
347 
348 static struct exynos_adc_data const exynos_adc_s3c2443_data = {
349 	.num_channels	= MAX_ADC_V1_CHANNELS,
350 	.mask		= ADC_S3C2410_DATX_MASK, /* 10 bit ADC resolution */
351 
352 	.init_hw	= exynos_adc_v1_init_hw,
353 	.exit_hw	= exynos_adc_v1_exit_hw,
354 	.start_conv	= exynos_adc_s3c2443_start_conv,
355 };
356 
357 static void exynos_adc_s3c64xx_start_conv(struct exynos_adc *info,
358 					  unsigned long addr)
359 {
360 	u32 con1;
361 
362 	con1 = readl(ADC_V1_CON(info->regs));
363 	con1 &= ~ADC_S3C2410_CON_SELMUX(0x7);
364 	con1 |= ADC_S3C2410_CON_SELMUX(addr);
365 	writel(con1 | ADC_CON_EN_START, ADC_V1_CON(info->regs));
366 }
367 
368 static struct exynos_adc_data const exynos_adc_s3c24xx_data = {
369 	.num_channels	= MAX_ADC_V1_CHANNELS,
370 	.mask		= ADC_S3C2410_DATX_MASK, /* 10 bit ADC resolution */
371 
372 	.init_hw	= exynos_adc_v1_init_hw,
373 	.exit_hw	= exynos_adc_v1_exit_hw,
374 	.start_conv	= exynos_adc_s3c64xx_start_conv,
375 };
376 
377 static struct exynos_adc_data const exynos_adc_s3c64xx_data = {
378 	.num_channels	= MAX_ADC_V1_CHANNELS,
379 	.mask		= ADC_DATX_MASK,	/* 12 bit ADC resolution */
380 
381 	.init_hw	= exynos_adc_v1_init_hw,
382 	.exit_hw	= exynos_adc_v1_exit_hw,
383 	.clear_irq	= exynos_adc_v1_clear_irq,
384 	.start_conv	= exynos_adc_s3c64xx_start_conv,
385 };
386 
387 static void exynos_adc_v2_init_hw(struct exynos_adc *info)
388 {
389 	u32 con1, con2;
390 
391 	if (info->data->needs_adc_phy)
392 		regmap_write(info->pmu_map, info->data->phy_offset, 1);
393 
394 	con1 = ADC_V2_CON1_SOFT_RESET;
395 	writel(con1, ADC_V2_CON1(info->regs));
396 
397 	con2 = ADC_V2_CON2_OSEL | ADC_V2_CON2_ESEL |
398 		ADC_V2_CON2_HIGHF | ADC_V2_CON2_C_TIME(0);
399 	writel(con2, ADC_V2_CON2(info->regs));
400 
401 	/* Enable interrupts */
402 	writel(1, ADC_V2_INT_EN(info->regs));
403 }
404 
405 static void exynos_adc_v2_exit_hw(struct exynos_adc *info)
406 {
407 	u32 con;
408 
409 	if (info->data->needs_adc_phy)
410 		regmap_write(info->pmu_map, info->data->phy_offset, 0);
411 
412 	con = readl(ADC_V2_CON1(info->regs));
413 	con &= ~ADC_CON_EN_START;
414 	writel(con, ADC_V2_CON1(info->regs));
415 }
416 
417 static void exynos_adc_v2_clear_irq(struct exynos_adc *info)
418 {
419 	writel(1, ADC_V2_INT_ST(info->regs));
420 }
421 
422 static void exynos_adc_v2_start_conv(struct exynos_adc *info,
423 				     unsigned long addr)
424 {
425 	u32 con1, con2;
426 
427 	con2 = readl(ADC_V2_CON2(info->regs));
428 	con2 &= ~ADC_V2_CON2_ACH_MASK;
429 	con2 |= ADC_V2_CON2_ACH_SEL(addr);
430 	writel(con2, ADC_V2_CON2(info->regs));
431 
432 	con1 = readl(ADC_V2_CON1(info->regs));
433 	writel(con1 | ADC_CON_EN_START, ADC_V2_CON1(info->regs));
434 }
435 
436 static const struct exynos_adc_data exynos_adc_v2_data = {
437 	.num_channels	= MAX_ADC_V2_CHANNELS,
438 	.mask		= ADC_DATX_MASK, /* 12 bit ADC resolution */
439 	.needs_adc_phy	= true,
440 	.phy_offset	= EXYNOS_ADCV2_PHY_OFFSET,
441 
442 	.init_hw	= exynos_adc_v2_init_hw,
443 	.exit_hw	= exynos_adc_v2_exit_hw,
444 	.clear_irq	= exynos_adc_v2_clear_irq,
445 	.start_conv	= exynos_adc_v2_start_conv,
446 };
447 
448 static const struct exynos_adc_data exynos3250_adc_data = {
449 	.num_channels	= MAX_EXYNOS3250_ADC_CHANNELS,
450 	.mask		= ADC_DATX_MASK, /* 12 bit ADC resolution */
451 	.needs_sclk	= true,
452 	.needs_adc_phy	= true,
453 	.phy_offset	= EXYNOS_ADCV1_PHY_OFFSET,
454 
455 	.init_hw	= exynos_adc_v2_init_hw,
456 	.exit_hw	= exynos_adc_v2_exit_hw,
457 	.clear_irq	= exynos_adc_v2_clear_irq,
458 	.start_conv	= exynos_adc_v2_start_conv,
459 };
460 
461 static void exynos_adc_exynos7_init_hw(struct exynos_adc *info)
462 {
463 	u32 con1, con2;
464 
465 	con1 = ADC_V2_CON1_SOFT_RESET;
466 	writel(con1, ADC_V2_CON1(info->regs));
467 
468 	con2 = readl(ADC_V2_CON2(info->regs));
469 	con2 &= ~ADC_V2_CON2_C_TIME(7);
470 	con2 |= ADC_V2_CON2_C_TIME(0);
471 	writel(con2, ADC_V2_CON2(info->regs));
472 
473 	/* Enable interrupts */
474 	writel(1, ADC_V2_INT_EN(info->regs));
475 }
476 
477 static const struct exynos_adc_data exynos7_adc_data = {
478 	.num_channels	= MAX_ADC_V1_CHANNELS,
479 	.mask		= ADC_DATX_MASK, /* 12 bit ADC resolution */
480 
481 	.init_hw	= exynos_adc_exynos7_init_hw,
482 	.exit_hw	= exynos_adc_v2_exit_hw,
483 	.clear_irq	= exynos_adc_v2_clear_irq,
484 	.start_conv	= exynos_adc_v2_start_conv,
485 };
486 
487 static const struct of_device_id exynos_adc_match[] = {
488 	{
489 		.compatible = "samsung,s3c2410-adc",
490 		.data = &exynos_adc_s3c24xx_data,
491 	}, {
492 		.compatible = "samsung,s3c2416-adc",
493 		.data = &exynos_adc_s3c2416_data,
494 	}, {
495 		.compatible = "samsung,s3c2440-adc",
496 		.data = &exynos_adc_s3c24xx_data,
497 	}, {
498 		.compatible = "samsung,s3c2443-adc",
499 		.data = &exynos_adc_s3c2443_data,
500 	}, {
501 		.compatible = "samsung,s3c6410-adc",
502 		.data = &exynos_adc_s3c64xx_data,
503 	}, {
504 		.compatible = "samsung,s5pv210-adc",
505 		.data = &exynos_adc_s5pv210_data,
506 	}, {
507 		.compatible = "samsung,exynos4212-adc",
508 		.data = &exynos4212_adc_data,
509 	}, {
510 		.compatible = "samsung,exynos-adc-v1",
511 		.data = &exynos_adc_v1_data,
512 	}, {
513 		.compatible = "samsung,exynos-adc-v2",
514 		.data = &exynos_adc_v2_data,
515 	}, {
516 		.compatible = "samsung,exynos3250-adc",
517 		.data = &exynos3250_adc_data,
518 	}, {
519 		.compatible = "samsung,exynos7-adc",
520 		.data = &exynos7_adc_data,
521 	},
522 	{ }
523 };
524 MODULE_DEVICE_TABLE(of, exynos_adc_match);
525 
526 static struct exynos_adc_data *exynos_adc_get_data(struct platform_device *pdev)
527 {
528 	const struct of_device_id *match;
529 
530 	match = of_match_node(exynos_adc_match, pdev->dev.of_node);
531 	return (struct exynos_adc_data *)match->data;
532 }
533 
534 static int exynos_read_raw(struct iio_dev *indio_dev,
535 				struct iio_chan_spec const *chan,
536 				int *val,
537 				int *val2,
538 				long mask)
539 {
540 	struct exynos_adc *info = iio_priv(indio_dev);
541 	unsigned long time_left;
542 	int ret;
543 
544 	if (mask == IIO_CHAN_INFO_SCALE) {
545 		ret = regulator_get_voltage(info->vdd);
546 		if (ret < 0)
547 			return ret;
548 
549 		/* Regulator voltage is in uV, but need mV */
550 		*val = ret / 1000;
551 		*val2 = info->data->mask;
552 
553 		return IIO_VAL_FRACTIONAL;
554 	} else if (mask != IIO_CHAN_INFO_RAW) {
555 		return -EINVAL;
556 	}
557 
558 	mutex_lock(&info->lock);
559 	reinit_completion(&info->completion);
560 
561 	/* Select the channel to be used and Trigger conversion */
562 	if (info->data->start_conv)
563 		info->data->start_conv(info, chan->address);
564 
565 	time_left = wait_for_completion_timeout(&info->completion,
566 						EXYNOS_ADC_TIMEOUT);
567 	if (time_left == 0) {
568 		dev_warn(&indio_dev->dev, "Conversion timed out! Resetting\n");
569 		if (info->data->init_hw)
570 			info->data->init_hw(info);
571 		ret = -ETIMEDOUT;
572 	} else {
573 		*val = info->value;
574 		*val2 = 0;
575 		ret = IIO_VAL_INT;
576 	}
577 
578 	mutex_unlock(&info->lock);
579 
580 	return ret;
581 }
582 
583 static int exynos_read_s3c64xx_ts(struct iio_dev *indio_dev, int *x, int *y)
584 {
585 	struct exynos_adc *info = iio_priv(indio_dev);
586 	unsigned long time_left;
587 	int ret;
588 
589 	mutex_lock(&info->lock);
590 	info->read_ts = true;
591 
592 	reinit_completion(&info->completion);
593 
594 	writel(ADC_S3C2410_TSC_PULL_UP_DISABLE | ADC_TSC_AUTOPST,
595 	       ADC_V1_TSC(info->regs));
596 
597 	/* Select the ts channel to be used and Trigger conversion */
598 	info->data->start_conv(info, ADC_S3C2410_MUX_TS);
599 
600 	time_left = wait_for_completion_timeout(&info->completion,
601 						EXYNOS_ADC_TIMEOUT);
602 	if (time_left == 0) {
603 		dev_warn(&indio_dev->dev, "Conversion timed out! Resetting\n");
604 		if (info->data->init_hw)
605 			info->data->init_hw(info);
606 		ret = -ETIMEDOUT;
607 	} else {
608 		*x = info->ts_x;
609 		*y = info->ts_y;
610 		ret = 0;
611 	}
612 
613 	info->read_ts = false;
614 	mutex_unlock(&info->lock);
615 
616 	return ret;
617 }
618 
619 static irqreturn_t exynos_adc_isr(int irq, void *dev_id)
620 {
621 	struct exynos_adc *info = dev_id;
622 	u32 mask = info->data->mask;
623 
624 	/* Read value */
625 	if (info->read_ts) {
626 		info->ts_x = readl(ADC_V1_DATX(info->regs));
627 		info->ts_y = readl(ADC_V1_DATY(info->regs));
628 		writel(ADC_TSC_WAIT4INT | ADC_S3C2443_TSC_UD_SEN, ADC_V1_TSC(info->regs));
629 	} else {
630 		info->value = readl(ADC_V1_DATX(info->regs)) & mask;
631 	}
632 
633 	/* clear irq */
634 	if (info->data->clear_irq)
635 		info->data->clear_irq(info);
636 
637 	complete(&info->completion);
638 
639 	return IRQ_HANDLED;
640 }
641 
642 /*
643  * Here we (ab)use a threaded interrupt handler to stay running
644  * for as long as the touchscreen remains pressed, we report
645  * a new event with the latest data and then sleep until the
646  * next timer tick. This mirrors the behavior of the old
647  * driver, with much less code.
648  */
649 static irqreturn_t exynos_ts_isr(int irq, void *dev_id)
650 {
651 	struct exynos_adc *info = dev_id;
652 	struct iio_dev *dev = dev_get_drvdata(info->dev);
653 	u32 x, y;
654 	bool pressed;
655 	int ret;
656 
657 	while (READ_ONCE(info->ts_enabled)) {
658 		ret = exynos_read_s3c64xx_ts(dev, &x, &y);
659 		if (ret == -ETIMEDOUT)
660 			break;
661 
662 		pressed = x & y & ADC_DATX_PRESSED;
663 		if (!pressed) {
664 			input_report_key(info->input, BTN_TOUCH, 0);
665 			input_sync(info->input);
666 			break;
667 		}
668 
669 		input_report_abs(info->input, ABS_X, x & ADC_DATX_MASK);
670 		input_report_abs(info->input, ABS_Y, y & ADC_DATY_MASK);
671 		input_report_key(info->input, BTN_TOUCH, 1);
672 		input_sync(info->input);
673 
674 		usleep_range(1000, 1100);
675 	}
676 
677 	writel(0, ADC_V1_CLRINTPNDNUP(info->regs));
678 
679 	return IRQ_HANDLED;
680 }
681 
682 static int exynos_adc_reg_access(struct iio_dev *indio_dev,
683 			      unsigned reg, unsigned writeval,
684 			      unsigned *readval)
685 {
686 	struct exynos_adc *info = iio_priv(indio_dev);
687 
688 	if (readval == NULL)
689 		return -EINVAL;
690 
691 	*readval = readl(info->regs + reg);
692 
693 	return 0;
694 }
695 
696 static const struct iio_info exynos_adc_iio_info = {
697 	.read_raw = &exynos_read_raw,
698 	.debugfs_reg_access = &exynos_adc_reg_access,
699 };
700 
701 #define ADC_CHANNEL(_index, _id) {			\
702 	.type = IIO_VOLTAGE,				\
703 	.indexed = 1,					\
704 	.channel = _index,				\
705 	.address = _index,				\
706 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
707 	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SCALE),	\
708 	.datasheet_name = _id,				\
709 }
710 
711 static const struct iio_chan_spec exynos_adc_iio_channels[] = {
712 	ADC_CHANNEL(0, "adc0"),
713 	ADC_CHANNEL(1, "adc1"),
714 	ADC_CHANNEL(2, "adc2"),
715 	ADC_CHANNEL(3, "adc3"),
716 	ADC_CHANNEL(4, "adc4"),
717 	ADC_CHANNEL(5, "adc5"),
718 	ADC_CHANNEL(6, "adc6"),
719 	ADC_CHANNEL(7, "adc7"),
720 	ADC_CHANNEL(8, "adc8"),
721 	ADC_CHANNEL(9, "adc9"),
722 };
723 
724 static int exynos_adc_remove_devices(struct device *dev, void *c)
725 {
726 	struct platform_device *pdev = to_platform_device(dev);
727 
728 	platform_device_unregister(pdev);
729 
730 	return 0;
731 }
732 
733 static int exynos_adc_ts_open(struct input_dev *dev)
734 {
735 	struct exynos_adc *info = input_get_drvdata(dev);
736 
737 	WRITE_ONCE(info->ts_enabled, true);
738 	enable_irq(info->tsirq);
739 
740 	return 0;
741 }
742 
743 static void exynos_adc_ts_close(struct input_dev *dev)
744 {
745 	struct exynos_adc *info = input_get_drvdata(dev);
746 
747 	WRITE_ONCE(info->ts_enabled, false);
748 	disable_irq(info->tsirq);
749 }
750 
751 static int exynos_adc_ts_init(struct exynos_adc *info)
752 {
753 	int ret;
754 
755 	if (info->tsirq <= 0)
756 		return -ENODEV;
757 
758 	info->input = input_allocate_device();
759 	if (!info->input)
760 		return -ENOMEM;
761 
762 	info->input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
763 	info->input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
764 
765 	input_set_abs_params(info->input, ABS_X, 0, 0x3FF, 0, 0);
766 	input_set_abs_params(info->input, ABS_Y, 0, 0x3FF, 0, 0);
767 
768 	info->input->name = "S3C24xx TouchScreen";
769 	info->input->id.bustype = BUS_HOST;
770 	info->input->open = exynos_adc_ts_open;
771 	info->input->close = exynos_adc_ts_close;
772 
773 	input_set_drvdata(info->input, info);
774 
775 	ret = input_register_device(info->input);
776 	if (ret) {
777 		input_free_device(info->input);
778 		return ret;
779 	}
780 
781 	ret = request_threaded_irq(info->tsirq, NULL, exynos_ts_isr,
782 				   IRQF_ONESHOT | IRQF_NO_AUTOEN,
783 				   "touchscreen", info);
784 	if (ret)
785 		input_unregister_device(info->input);
786 
787 	return ret;
788 }
789 
790 static int exynos_adc_probe(struct platform_device *pdev)
791 {
792 	struct exynos_adc *info = NULL;
793 	struct device_node *np = pdev->dev.of_node;
794 	struct s3c2410_ts_mach_info *pdata = dev_get_platdata(&pdev->dev);
795 	struct iio_dev *indio_dev = NULL;
796 	bool has_ts = false;
797 	int ret;
798 	int irq;
799 
800 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(struct exynos_adc));
801 	if (!indio_dev) {
802 		dev_err(&pdev->dev, "failed allocating iio device\n");
803 		return -ENOMEM;
804 	}
805 
806 	info = iio_priv(indio_dev);
807 
808 	info->data = exynos_adc_get_data(pdev);
809 	if (!info->data) {
810 		dev_err(&pdev->dev, "failed getting exynos_adc_data\n");
811 		return -EINVAL;
812 	}
813 
814 	info->regs = devm_platform_ioremap_resource(pdev, 0);
815 	if (IS_ERR(info->regs))
816 		return PTR_ERR(info->regs);
817 
818 
819 	if (info->data->needs_adc_phy) {
820 		info->pmu_map = syscon_regmap_lookup_by_phandle(
821 					pdev->dev.of_node,
822 					"samsung,syscon-phandle");
823 		if (IS_ERR(info->pmu_map)) {
824 			dev_err(&pdev->dev, "syscon regmap lookup failed.\n");
825 			return PTR_ERR(info->pmu_map);
826 		}
827 	}
828 
829 	/* leave out any TS related code if unreachable */
830 	if (IS_REACHABLE(CONFIG_INPUT)) {
831 		has_ts = of_property_read_bool(pdev->dev.of_node,
832 					       "has-touchscreen") || pdata;
833 	}
834 
835 	irq = platform_get_irq(pdev, 0);
836 	if (irq < 0)
837 		return irq;
838 	info->irq = irq;
839 
840 	if (has_ts) {
841 		irq = platform_get_irq(pdev, 1);
842 		if (irq == -EPROBE_DEFER)
843 			return irq;
844 
845 		info->tsirq = irq;
846 	} else {
847 		info->tsirq = -1;
848 	}
849 
850 	info->dev = &pdev->dev;
851 
852 	init_completion(&info->completion);
853 
854 	info->clk = devm_clk_get(&pdev->dev, "adc");
855 	if (IS_ERR(info->clk)) {
856 		dev_err(&pdev->dev, "failed getting clock, err = %ld\n",
857 							PTR_ERR(info->clk));
858 		return PTR_ERR(info->clk);
859 	}
860 
861 	if (info->data->needs_sclk) {
862 		info->sclk = devm_clk_get(&pdev->dev, "sclk");
863 		if (IS_ERR(info->sclk)) {
864 			dev_err(&pdev->dev,
865 				"failed getting sclk clock, err = %ld\n",
866 				PTR_ERR(info->sclk));
867 			return PTR_ERR(info->sclk);
868 		}
869 	}
870 
871 	info->vdd = devm_regulator_get(&pdev->dev, "vdd");
872 	if (IS_ERR(info->vdd))
873 		return dev_err_probe(&pdev->dev, PTR_ERR(info->vdd),
874 				     "failed getting regulator");
875 
876 	ret = regulator_enable(info->vdd);
877 	if (ret)
878 		return ret;
879 
880 	ret = exynos_adc_prepare_clk(info);
881 	if (ret)
882 		goto err_disable_reg;
883 
884 	ret = exynos_adc_enable_clk(info);
885 	if (ret)
886 		goto err_unprepare_clk;
887 
888 	platform_set_drvdata(pdev, indio_dev);
889 
890 	indio_dev->name = dev_name(&pdev->dev);
891 	indio_dev->info = &exynos_adc_iio_info;
892 	indio_dev->modes = INDIO_DIRECT_MODE;
893 	indio_dev->channels = exynos_adc_iio_channels;
894 	indio_dev->num_channels = info->data->num_channels;
895 
896 	mutex_init(&info->lock);
897 
898 	ret = request_irq(info->irq, exynos_adc_isr,
899 					0, dev_name(&pdev->dev), info);
900 	if (ret < 0) {
901 		dev_err(&pdev->dev, "failed requesting irq, irq = %d\n",
902 							info->irq);
903 		goto err_disable_clk;
904 	}
905 
906 	ret = iio_device_register(indio_dev);
907 	if (ret)
908 		goto err_irq;
909 
910 	if (info->data->init_hw)
911 		info->data->init_hw(info);
912 
913 	if (pdata)
914 		info->delay = pdata->delay;
915 	else
916 		info->delay = 10000;
917 
918 	if (has_ts)
919 		ret = exynos_adc_ts_init(info);
920 	if (ret)
921 		goto err_iio;
922 
923 	ret = of_platform_populate(np, exynos_adc_match, NULL, &indio_dev->dev);
924 	if (ret < 0) {
925 		dev_err(&pdev->dev, "failed adding child nodes\n");
926 		goto err_of_populate;
927 	}
928 
929 	return 0;
930 
931 err_of_populate:
932 	device_for_each_child(&indio_dev->dev, NULL,
933 				exynos_adc_remove_devices);
934 	if (has_ts) {
935 		input_unregister_device(info->input);
936 		free_irq(info->tsirq, info);
937 	}
938 err_iio:
939 	iio_device_unregister(indio_dev);
940 err_irq:
941 	free_irq(info->irq, info);
942 err_disable_clk:
943 	if (info->data->exit_hw)
944 		info->data->exit_hw(info);
945 	exynos_adc_disable_clk(info);
946 err_unprepare_clk:
947 	exynos_adc_unprepare_clk(info);
948 err_disable_reg:
949 	regulator_disable(info->vdd);
950 	return ret;
951 }
952 
953 static void exynos_adc_remove(struct platform_device *pdev)
954 {
955 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
956 	struct exynos_adc *info = iio_priv(indio_dev);
957 
958 	if (IS_REACHABLE(CONFIG_INPUT) && info->input) {
959 		free_irq(info->tsirq, info);
960 		input_unregister_device(info->input);
961 	}
962 	device_for_each_child(&indio_dev->dev, NULL,
963 				exynos_adc_remove_devices);
964 	iio_device_unregister(indio_dev);
965 	free_irq(info->irq, info);
966 	if (info->data->exit_hw)
967 		info->data->exit_hw(info);
968 	exynos_adc_disable_clk(info);
969 	exynos_adc_unprepare_clk(info);
970 	regulator_disable(info->vdd);
971 }
972 
973 static int exynos_adc_suspend(struct device *dev)
974 {
975 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
976 	struct exynos_adc *info = iio_priv(indio_dev);
977 
978 	if (info->data->exit_hw)
979 		info->data->exit_hw(info);
980 	exynos_adc_disable_clk(info);
981 	regulator_disable(info->vdd);
982 
983 	return 0;
984 }
985 
986 static int exynos_adc_resume(struct device *dev)
987 {
988 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
989 	struct exynos_adc *info = iio_priv(indio_dev);
990 	int ret;
991 
992 	ret = regulator_enable(info->vdd);
993 	if (ret)
994 		return ret;
995 
996 	ret = exynos_adc_enable_clk(info);
997 	if (ret)
998 		return ret;
999 
1000 	if (info->data->init_hw)
1001 		info->data->init_hw(info);
1002 
1003 	return 0;
1004 }
1005 
1006 static DEFINE_SIMPLE_DEV_PM_OPS(exynos_adc_pm_ops, exynos_adc_suspend,
1007 				exynos_adc_resume);
1008 
1009 static struct platform_driver exynos_adc_driver = {
1010 	.probe		= exynos_adc_probe,
1011 	.remove		= exynos_adc_remove,
1012 	.driver		= {
1013 		.name	= "exynos-adc",
1014 		.of_match_table = exynos_adc_match,
1015 		.pm	= pm_sleep_ptr(&exynos_adc_pm_ops),
1016 	},
1017 };
1018 
1019 module_platform_driver(exynos_adc_driver);
1020 
1021 MODULE_AUTHOR("Naveen Krishna Chatradhi <ch.naveen@samsung.com>");
1022 MODULE_DESCRIPTION("Samsung EXYNOS5 ADC driver");
1023 MODULE_LICENSE("GPL v2");
1024