1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Driver for the ADC present in the Atmel AT91 evaluation boards.
4 *
5 * Copyright 2011 Free Electrons
6 */
7
8#include <linux/bitmap.h>
9#include <linux/bitops.h>
10#include <linux/clk.h>
11#include <linux/err.h>
12#include <linux/io.h>
13#include <linux/input.h>
14#include <linux/interrupt.h>
15#include <linux/jiffies.h>
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/of.h>
19#include <linux/platform_device.h>
20#include <linux/sched.h>
21#include <linux/slab.h>
22#include <linux/wait.h>
23
24#include <linux/iio/iio.h>
25#include <linux/iio/buffer.h>
26#include <linux/iio/trigger.h>
27#include <linux/iio/trigger_consumer.h>
28#include <linux/iio/triggered_buffer.h>
29#include <linux/pinctrl/consumer.h>
30
31/* Registers */
32#define AT91_ADC_CR		0x00		/* Control Register */
33#define		AT91_ADC_SWRST		(1 << 0)	/* Software Reset */
34#define		AT91_ADC_START		(1 << 1)	/* Start Conversion */
35
36#define AT91_ADC_MR		0x04		/* Mode Register */
37#define		AT91_ADC_TSAMOD		(3 << 0)	/* ADC mode */
38#define		AT91_ADC_TSAMOD_ADC_ONLY_MODE		(0 << 0)	/* ADC Mode */
39#define		AT91_ADC_TSAMOD_TS_ONLY_MODE		(1 << 0)	/* Touch Screen Only Mode */
40#define		AT91_ADC_TRGEN		(1 << 0)	/* Trigger Enable */
41#define		AT91_ADC_TRGSEL		(7 << 1)	/* Trigger Selection */
42#define			AT91_ADC_TRGSEL_TC0		(0 << 1)
43#define			AT91_ADC_TRGSEL_TC1		(1 << 1)
44#define			AT91_ADC_TRGSEL_TC2		(2 << 1)
45#define			AT91_ADC_TRGSEL_EXTERNAL	(6 << 1)
46#define		AT91_ADC_LOWRES		(1 << 4)	/* Low Resolution */
47#define		AT91_ADC_SLEEP		(1 << 5)	/* Sleep Mode */
48#define		AT91_ADC_PENDET		(1 << 6)	/* Pen contact detection enable */
49#define		AT91_ADC_PRESCAL_9260	(0x3f << 8)	/* Prescalar Rate Selection */
50#define		AT91_ADC_PRESCAL_9G45	(0xff << 8)
51#define			AT91_ADC_PRESCAL_(x)	((x) << 8)
52#define		AT91_ADC_STARTUP_9260	(0x1f << 16)	/* Startup Up Time */
53#define		AT91_ADC_STARTUP_9G45	(0x7f << 16)
54#define		AT91_ADC_STARTUP_9X5	(0xf << 16)
55#define			AT91_ADC_STARTUP_(x)	((x) << 16)
56#define		AT91_ADC_SHTIM		(0xf  << 24)	/* Sample & Hold Time */
57#define			AT91_ADC_SHTIM_(x)	((x) << 24)
58#define		AT91_ADC_PENDBC		(0x0f << 28)	/* Pen Debounce time */
59#define			AT91_ADC_PENDBC_(x)	((x) << 28)
60
61#define AT91_ADC_TSR		0x0C
62#define		AT91_ADC_TSR_SHTIM	(0xf  << 24)	/* Sample & Hold Time */
63#define			AT91_ADC_TSR_SHTIM_(x)	((x) << 24)
64
65#define AT91_ADC_CHER		0x10		/* Channel Enable Register */
66#define AT91_ADC_CHDR		0x14		/* Channel Disable Register */
67#define AT91_ADC_CHSR		0x18		/* Channel Status Register */
68#define		AT91_ADC_CH(n)		(1 << (n))	/* Channel Number */
69
70#define AT91_ADC_SR		0x1C		/* Status Register */
71#define		AT91_ADC_EOC(n)		(1 << (n))	/* End of Conversion on Channel N */
72#define		AT91_ADC_OVRE(n)	(1 << ((n) + 8))/* Overrun Error on Channel N */
73#define		AT91_ADC_DRDY		(1 << 16)	/* Data Ready */
74#define		AT91_ADC_GOVRE		(1 << 17)	/* General Overrun Error */
75#define		AT91_ADC_ENDRX		(1 << 18)	/* End of RX Buffer */
76#define		AT91_ADC_RXFUFF		(1 << 19)	/* RX Buffer Full */
77
78#define AT91_ADC_SR_9X5		0x30		/* Status Register for 9x5 */
79#define		AT91_ADC_SR_DRDY_9X5	(1 << 24)	/* Data Ready */
80
81#define AT91_ADC_LCDR		0x20		/* Last Converted Data Register */
82#define		AT91_ADC_LDATA		(0x3ff)
83
84#define AT91_ADC_IER		0x24		/* Interrupt Enable Register */
85#define AT91_ADC_IDR		0x28		/* Interrupt Disable Register */
86#define AT91_ADC_IMR		0x2C		/* Interrupt Mask Register */
87#define		AT91RL_ADC_IER_PEN	(1 << 20)
88#define		AT91RL_ADC_IER_NOPEN	(1 << 21)
89#define		AT91_ADC_IER_PEN	(1 << 29)
90#define		AT91_ADC_IER_NOPEN	(1 << 30)
91#define		AT91_ADC_IER_XRDY	(1 << 20)
92#define		AT91_ADC_IER_YRDY	(1 << 21)
93#define		AT91_ADC_IER_PRDY	(1 << 22)
94#define		AT91_ADC_ISR_PENS	(1 << 31)
95
96#define AT91_ADC_CHR(n)		(0x30 + ((n) * 4))	/* Channel Data Register N */
97#define		AT91_ADC_DATA		(0x3ff)
98
99#define AT91_ADC_CDR0_9X5	(0x50)			/* Channel Data Register 0 for 9X5 */
100
101#define AT91_ADC_ACR		0x94	/* Analog Control Register */
102#define		AT91_ADC_ACR_PENDETSENS	(0x3 << 0)	/* pull-up resistor */
103
104#define AT91_ADC_TSMR		0xB0
105#define		AT91_ADC_TSMR_TSMODE	(3 << 0)	/* Touch Screen Mode */
106#define			AT91_ADC_TSMR_TSMODE_NONE		(0 << 0)
107#define			AT91_ADC_TSMR_TSMODE_4WIRE_NO_PRESS	(1 << 0)
108#define			AT91_ADC_TSMR_TSMODE_4WIRE_PRESS	(2 << 0)
109#define			AT91_ADC_TSMR_TSMODE_5WIRE		(3 << 0)
110#define		AT91_ADC_TSMR_TSAV	(3 << 4)	/* Averages samples */
111#define			AT91_ADC_TSMR_TSAV_(x)		((x) << 4)
112#define		AT91_ADC_TSMR_SCTIM	(0x0f << 16)	/* Switch closure time */
113#define			AT91_ADC_TSMR_SCTIM_(x)		((x) << 16)
114#define		AT91_ADC_TSMR_PENDBC	(0x0f << 28)	/* Pen Debounce time */
115#define			AT91_ADC_TSMR_PENDBC_(x)	((x) << 28)
116#define		AT91_ADC_TSMR_NOTSDMA	(1 << 22)	/* No Touchscreen DMA */
117#define		AT91_ADC_TSMR_PENDET_DIS	(0 << 24)	/* Pen contact detection disable */
118#define		AT91_ADC_TSMR_PENDET_ENA	(1 << 24)	/* Pen contact detection enable */
119
120#define AT91_ADC_TSXPOSR	0xB4
121#define AT91_ADC_TSYPOSR	0xB8
122#define AT91_ADC_TSPRESSR	0xBC
123
124#define AT91_ADC_TRGR_9260	AT91_ADC_MR
125#define AT91_ADC_TRGR_9G45	0x08
126#define AT91_ADC_TRGR_9X5	0xC0
127
128/* Trigger Register bit field */
129#define		AT91_ADC_TRGR_TRGPER	(0xffff << 16)
130#define			AT91_ADC_TRGR_TRGPER_(x)	((x) << 16)
131#define		AT91_ADC_TRGR_TRGMOD	(0x7 << 0)
132#define			AT91_ADC_TRGR_NONE		(0 << 0)
133#define			AT91_ADC_TRGR_MOD_PERIOD_TRIG	(5 << 0)
134
135#define AT91_ADC_CHAN(st, ch) \
136	(st->registers->channel_base + (ch * 4))
137#define at91_adc_readl(st, reg) \
138	(readl_relaxed(st->reg_base + reg))
139#define at91_adc_writel(st, reg, val) \
140	(writel_relaxed(val, st->reg_base + reg))
141
142#define DRIVER_NAME		"at91_adc"
143#define MAX_POS_BITS		12
144
145#define TOUCH_SAMPLE_PERIOD_US		2000	/* 2ms */
146#define TOUCH_PEN_DETECT_DEBOUNCE_US	200
147
148#define MAX_RLPOS_BITS         10
149#define TOUCH_SAMPLE_PERIOD_US_RL      10000   /* 10ms, the SoC can't keep up with 2ms */
150#define TOUCH_SHTIM                    0xa
151#define TOUCH_SCTIM_US		10		/* 10us for the Touchscreen Switches Closure Time */
152
153enum atmel_adc_ts_type {
154	ATMEL_ADC_TOUCHSCREEN_NONE = 0,
155	ATMEL_ADC_TOUCHSCREEN_4WIRE = 4,
156	ATMEL_ADC_TOUCHSCREEN_5WIRE = 5,
157};
158
159/**
160 * struct at91_adc_trigger - description of triggers
161 * @name:		name of the trigger advertised to the user
162 * @value:		value to set in the ADC's trigger setup register
163 *			to enable the trigger
164 * @is_external:	Does the trigger rely on an external pin?
165 */
166struct at91_adc_trigger {
167	const char	*name;
168	u8		value;
169	bool		is_external;
170};
171
172/**
173 * struct at91_adc_reg_desc - Various informations relative to registers
174 * @channel_base:	Base offset for the channel data registers
175 * @drdy_mask:		Mask of the DRDY field in the relevant registers
176 *			(Interruptions registers mostly)
177 * @status_register:	Offset of the Interrupt Status Register
178 * @trigger_register:	Offset of the Trigger setup register
179 * @mr_prescal_mask:	Mask of the PRESCAL field in the adc MR register
180 * @mr_startup_mask:	Mask of the STARTUP field in the adc MR register
181 */
182struct at91_adc_reg_desc {
183	u8	channel_base;
184	u32	drdy_mask;
185	u8	status_register;
186	u8	trigger_register;
187	u32	mr_prescal_mask;
188	u32	mr_startup_mask;
189};
190
191struct at91_adc_caps {
192	bool	has_ts;		/* Support touch screen */
193	bool	has_tsmr;	/* only at91sam9x5, sama5d3 have TSMR reg */
194	/*
195	 * Numbers of sampling data will be averaged. Can be 0~3.
196	 * Hardware can average (2 ^ ts_filter_average) sample data.
197	 */
198	u8	ts_filter_average;
199	/* Pen Detection input pull-up resistor, can be 0~3 */
200	u8	ts_pen_detect_sensitivity;
201
202	/* startup time calculate function */
203	u32 (*calc_startup_ticks)(u32 startup_time, u32 adc_clk_khz);
204
205	u8	num_channels;
206
207	u8	low_res_bits;
208	u8	high_res_bits;
209	u32	trigger_number;
210	const struct at91_adc_trigger *triggers;
211	struct at91_adc_reg_desc registers;
212};
213
214struct at91_adc_state {
215	struct clk		*adc_clk;
216	u16			*buffer;
217	unsigned long		channels_mask;
218	struct clk		*clk;
219	bool			done;
220	int			irq;
221	u16			last_value;
222	int			chnb;
223	struct mutex		lock;
224	u8			num_channels;
225	void __iomem		*reg_base;
226	const struct at91_adc_reg_desc *registers;
227	u32			startup_time;
228	u8			sample_hold_time;
229	bool			sleep_mode;
230	struct iio_trigger	**trig;
231	bool			use_external;
232	u32			vref_mv;
233	u32			res;		/* resolution used for convertions */
234	wait_queue_head_t	wq_data_avail;
235	const struct at91_adc_caps	*caps;
236
237	/*
238	 * Following ADC channels are shared by touchscreen:
239	 *
240	 * CH0 -- Touch screen XP/UL
241	 * CH1 -- Touch screen XM/UR
242	 * CH2 -- Touch screen YP/LL
243	 * CH3 -- Touch screen YM/Sense
244	 * CH4 -- Touch screen LR(5-wire only)
245	 *
246	 * The bitfields below represents the reserved channel in the
247	 * touchscreen mode.
248	 */
249#define CHAN_MASK_TOUCHSCREEN_4WIRE	(0xf << 0)
250#define CHAN_MASK_TOUCHSCREEN_5WIRE	(0x1f << 0)
251	enum atmel_adc_ts_type	touchscreen_type;
252	struct input_dev	*ts_input;
253
254	u16			ts_sample_period_val;
255	u32			ts_pressure_threshold;
256	u16			ts_pendbc;
257
258	bool			ts_bufferedmeasure;
259	u32			ts_prev_absx;
260	u32			ts_prev_absy;
261};
262
263static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
264{
265	struct iio_poll_func *pf = p;
266	struct iio_dev *idev = pf->indio_dev;
267	struct at91_adc_state *st = iio_priv(idev);
268	struct iio_chan_spec const *chan;
269	int i, j = 0;
270
271	for (i = 0; i < idev->masklength; i++) {
272		if (!test_bit(i, idev->active_scan_mask))
273			continue;
274		chan = idev->channels + i;
275		st->buffer[j] = at91_adc_readl(st, AT91_ADC_CHAN(st, chan->channel));
276		j++;
277	}
278
279	iio_push_to_buffers_with_timestamp(idev, st->buffer, pf->timestamp);
280
281	iio_trigger_notify_done(idev->trig);
282
283	/* Needed to ACK the DRDY interruption */
284	at91_adc_readl(st, AT91_ADC_LCDR);
285
286	enable_irq(st->irq);
287
288	return IRQ_HANDLED;
289}
290
291/* Handler for classic adc channel eoc trigger */
292static void handle_adc_eoc_trigger(int irq, struct iio_dev *idev)
293{
294	struct at91_adc_state *st = iio_priv(idev);
295
296	if (iio_buffer_enabled(idev)) {
297		disable_irq_nosync(irq);
298		iio_trigger_poll(idev->trig);
299	} else {
300		st->last_value = at91_adc_readl(st, AT91_ADC_CHAN(st, st->chnb));
301		/* Needed to ACK the DRDY interruption */
302		at91_adc_readl(st, AT91_ADC_LCDR);
303		st->done = true;
304		wake_up_interruptible(&st->wq_data_avail);
305	}
306}
307
308static int at91_ts_sample(struct iio_dev *idev)
309{
310	struct at91_adc_state *st = iio_priv(idev);
311	unsigned int xscale, yscale, reg, z1, z2;
312	unsigned int x, y, pres, xpos, ypos;
313	unsigned int rxp = 1;
314	unsigned int factor = 1000;
315
316	unsigned int xyz_mask_bits = st->res;
317	unsigned int xyz_mask = (1 << xyz_mask_bits) - 1;
318
319	/* calculate position */
320	/* x position = (x / xscale) * max, max = 2^MAX_POS_BITS - 1 */
321	reg = at91_adc_readl(st, AT91_ADC_TSXPOSR);
322	xpos = reg & xyz_mask;
323	x = (xpos << MAX_POS_BITS) - xpos;
324	xscale = (reg >> 16) & xyz_mask;
325	if (xscale == 0) {
326		dev_err(&idev->dev, "Error: xscale == 0!\n");
327		return -1;
328	}
329	x /= xscale;
330
331	/* y position = (y / yscale) * max, max = 2^MAX_POS_BITS - 1 */
332	reg = at91_adc_readl(st, AT91_ADC_TSYPOSR);
333	ypos = reg & xyz_mask;
334	y = (ypos << MAX_POS_BITS) - ypos;
335	yscale = (reg >> 16) & xyz_mask;
336	if (yscale == 0) {
337		dev_err(&idev->dev, "Error: yscale == 0!\n");
338		return -1;
339	}
340	y /= yscale;
341
342	/* calculate the pressure */
343	reg = at91_adc_readl(st, AT91_ADC_TSPRESSR);
344	z1 = reg & xyz_mask;
345	z2 = (reg >> 16) & xyz_mask;
346
347	if (z1 != 0)
348		pres = rxp * (x * factor / 1024) * (z2 * factor / z1 - factor)
349			/ factor;
350	else
351		pres = st->ts_pressure_threshold;	/* no pen contacted */
352
353	dev_dbg(&idev->dev, "xpos = %d, xscale = %d, ypos = %d, yscale = %d, z1 = %d, z2 = %d, press = %d\n",
354				xpos, xscale, ypos, yscale, z1, z2, pres);
355
356	if (pres < st->ts_pressure_threshold) {
357		dev_dbg(&idev->dev, "x = %d, y = %d, pressure = %d\n",
358					x, y, pres / factor);
359		input_report_abs(st->ts_input, ABS_X, x);
360		input_report_abs(st->ts_input, ABS_Y, y);
361		input_report_abs(st->ts_input, ABS_PRESSURE, pres);
362		input_report_key(st->ts_input, BTN_TOUCH, 1);
363		input_sync(st->ts_input);
364	} else {
365		dev_dbg(&idev->dev, "pressure too low: not reporting\n");
366	}
367
368	return 0;
369}
370
371static irqreturn_t at91_adc_rl_interrupt(int irq, void *private)
372{
373	struct iio_dev *idev = private;
374	struct at91_adc_state *st = iio_priv(idev);
375	u32 status = at91_adc_readl(st, st->registers->status_register);
376	unsigned int reg;
377
378	status &= at91_adc_readl(st, AT91_ADC_IMR);
379	if (status & GENMASK(st->num_channels - 1, 0))
380		handle_adc_eoc_trigger(irq, idev);
381
382	if (status & AT91RL_ADC_IER_PEN) {
383		/* Disabling pen debounce is required to get a NOPEN irq */
384		reg = at91_adc_readl(st, AT91_ADC_MR);
385		reg &= ~AT91_ADC_PENDBC;
386		at91_adc_writel(st, AT91_ADC_MR, reg);
387
388		at91_adc_writel(st, AT91_ADC_IDR, AT91RL_ADC_IER_PEN);
389		at91_adc_writel(st, AT91_ADC_IER, AT91RL_ADC_IER_NOPEN
390				| AT91_ADC_EOC(3));
391		/* Set up period trigger for sampling */
392		at91_adc_writel(st, st->registers->trigger_register,
393			AT91_ADC_TRGR_MOD_PERIOD_TRIG |
394			AT91_ADC_TRGR_TRGPER_(st->ts_sample_period_val));
395	} else if (status & AT91RL_ADC_IER_NOPEN) {
396		reg = at91_adc_readl(st, AT91_ADC_MR);
397		reg |= AT91_ADC_PENDBC_(st->ts_pendbc) & AT91_ADC_PENDBC;
398		at91_adc_writel(st, AT91_ADC_MR, reg);
399		at91_adc_writel(st, st->registers->trigger_register,
400			AT91_ADC_TRGR_NONE);
401
402		at91_adc_writel(st, AT91_ADC_IDR, AT91RL_ADC_IER_NOPEN
403				| AT91_ADC_EOC(3));
404		at91_adc_writel(st, AT91_ADC_IER, AT91RL_ADC_IER_PEN);
405		st->ts_bufferedmeasure = false;
406		input_report_key(st->ts_input, BTN_TOUCH, 0);
407		input_sync(st->ts_input);
408	} else if (status & AT91_ADC_EOC(3) && st->ts_input) {
409		/* Conversion finished and we've a touchscreen */
410		if (st->ts_bufferedmeasure) {
411			/*
412			 * Last measurement is always discarded, since it can
413			 * be erroneous.
414			 * Always report previous measurement
415			 */
416			input_report_abs(st->ts_input, ABS_X, st->ts_prev_absx);
417			input_report_abs(st->ts_input, ABS_Y, st->ts_prev_absy);
418			input_report_key(st->ts_input, BTN_TOUCH, 1);
419			input_sync(st->ts_input);
420		} else
421			st->ts_bufferedmeasure = true;
422
423		/* Now make new measurement */
424		st->ts_prev_absx = at91_adc_readl(st, AT91_ADC_CHAN(st, 3))
425				   << MAX_RLPOS_BITS;
426		st->ts_prev_absx /= at91_adc_readl(st, AT91_ADC_CHAN(st, 2));
427
428		st->ts_prev_absy = at91_adc_readl(st, AT91_ADC_CHAN(st, 1))
429				   << MAX_RLPOS_BITS;
430		st->ts_prev_absy /= at91_adc_readl(st, AT91_ADC_CHAN(st, 0));
431	}
432
433	return IRQ_HANDLED;
434}
435
436static irqreturn_t at91_adc_9x5_interrupt(int irq, void *private)
437{
438	struct iio_dev *idev = private;
439	struct at91_adc_state *st = iio_priv(idev);
440	u32 status = at91_adc_readl(st, st->registers->status_register);
441	const uint32_t ts_data_irq_mask =
442		AT91_ADC_IER_XRDY |
443		AT91_ADC_IER_YRDY |
444		AT91_ADC_IER_PRDY;
445
446	if (status & GENMASK(st->num_channels - 1, 0))
447		handle_adc_eoc_trigger(irq, idev);
448
449	if (status & AT91_ADC_IER_PEN) {
450		at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_PEN);
451		at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_NOPEN |
452			ts_data_irq_mask);
453		/* Set up period trigger for sampling */
454		at91_adc_writel(st, st->registers->trigger_register,
455			AT91_ADC_TRGR_MOD_PERIOD_TRIG |
456			AT91_ADC_TRGR_TRGPER_(st->ts_sample_period_val));
457	} else if (status & AT91_ADC_IER_NOPEN) {
458		at91_adc_writel(st, st->registers->trigger_register, 0);
459		at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_NOPEN |
460			ts_data_irq_mask);
461		at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_PEN);
462
463		input_report_key(st->ts_input, BTN_TOUCH, 0);
464		input_sync(st->ts_input);
465	} else if ((status & ts_data_irq_mask) == ts_data_irq_mask) {
466		/* Now all touchscreen data is ready */
467
468		if (status & AT91_ADC_ISR_PENS) {
469			/* validate data by pen contact */
470			at91_ts_sample(idev);
471		} else {
472			/* triggered by event that is no pen contact, just read
473			 * them to clean the interrupt and discard all.
474			 */
475			at91_adc_readl(st, AT91_ADC_TSXPOSR);
476			at91_adc_readl(st, AT91_ADC_TSYPOSR);
477			at91_adc_readl(st, AT91_ADC_TSPRESSR);
478		}
479	}
480
481	return IRQ_HANDLED;
482}
483
484static int at91_adc_channel_init(struct iio_dev *idev)
485{
486	struct at91_adc_state *st = iio_priv(idev);
487	struct iio_chan_spec *chan_array, *timestamp;
488	int bit, idx = 0;
489	unsigned long rsvd_mask = 0;
490
491	/* If touchscreen is enable, then reserve the adc channels */
492	if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_4WIRE)
493		rsvd_mask = CHAN_MASK_TOUCHSCREEN_4WIRE;
494	else if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_5WIRE)
495		rsvd_mask = CHAN_MASK_TOUCHSCREEN_5WIRE;
496
497	/* set up the channel mask to reserve touchscreen channels */
498	st->channels_mask &= ~rsvd_mask;
499
500	idev->num_channels = bitmap_weight(&st->channels_mask,
501					   st->num_channels) + 1;
502
503	chan_array = devm_kzalloc(&idev->dev,
504				  ((idev->num_channels + 1) *
505					sizeof(struct iio_chan_spec)),
506				  GFP_KERNEL);
507
508	if (!chan_array)
509		return -ENOMEM;
510
511	for_each_set_bit(bit, &st->channels_mask, st->num_channels) {
512		struct iio_chan_spec *chan = chan_array + idx;
513
514		chan->type = IIO_VOLTAGE;
515		chan->indexed = 1;
516		chan->channel = bit;
517		chan->scan_index = idx;
518		chan->scan_type.sign = 'u';
519		chan->scan_type.realbits = st->res;
520		chan->scan_type.storagebits = 16;
521		chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE);
522		chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);
523		idx++;
524	}
525	timestamp = chan_array + idx;
526
527	timestamp->type = IIO_TIMESTAMP;
528	timestamp->channel = -1;
529	timestamp->scan_index = idx;
530	timestamp->scan_type.sign = 's';
531	timestamp->scan_type.realbits = 64;
532	timestamp->scan_type.storagebits = 64;
533
534	idev->channels = chan_array;
535	return idev->num_channels;
536}
537
538static int at91_adc_get_trigger_value_by_name(struct iio_dev *idev,
539					     const struct at91_adc_trigger *triggers,
540					     const char *trigger_name)
541{
542	struct at91_adc_state *st = iio_priv(idev);
543	int i;
544
545	for (i = 0; i < st->caps->trigger_number; i++) {
546		char *name = kasprintf(GFP_KERNEL,
547				"%s-dev%d-%s",
548				idev->name,
549				iio_device_id(idev),
550				triggers[i].name);
551		if (!name)
552			return -ENOMEM;
553
554		if (strcmp(trigger_name, name) == 0) {
555			kfree(name);
556			if (triggers[i].value == 0)
557				return -EINVAL;
558			return triggers[i].value;
559		}
560
561		kfree(name);
562	}
563
564	return -EINVAL;
565}
566
567static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
568{
569	struct iio_dev *idev = iio_trigger_get_drvdata(trig);
570	struct at91_adc_state *st = iio_priv(idev);
571	const struct at91_adc_reg_desc *reg = st->registers;
572	u32 status = at91_adc_readl(st, reg->trigger_register);
573	int value;
574	u8 bit;
575
576	value = at91_adc_get_trigger_value_by_name(idev,
577						   st->caps->triggers,
578						   idev->trig->name);
579	if (value < 0)
580		return value;
581
582	if (state) {
583		st->buffer = kmalloc(idev->scan_bytes, GFP_KERNEL);
584		if (st->buffer == NULL)
585			return -ENOMEM;
586
587		at91_adc_writel(st, reg->trigger_register,
588				status | value);
589
590		for_each_set_bit(bit, idev->active_scan_mask,
591				 st->num_channels) {
592			struct iio_chan_spec const *chan = idev->channels + bit;
593			at91_adc_writel(st, AT91_ADC_CHER,
594					AT91_ADC_CH(chan->channel));
595		}
596
597		at91_adc_writel(st, AT91_ADC_IER, reg->drdy_mask);
598
599	} else {
600		at91_adc_writel(st, AT91_ADC_IDR, reg->drdy_mask);
601
602		at91_adc_writel(st, reg->trigger_register,
603				status & ~value);
604
605		for_each_set_bit(bit, idev->active_scan_mask,
606				 st->num_channels) {
607			struct iio_chan_spec const *chan = idev->channels + bit;
608			at91_adc_writel(st, AT91_ADC_CHDR,
609					AT91_ADC_CH(chan->channel));
610		}
611		kfree(st->buffer);
612	}
613
614	return 0;
615}
616
617static const struct iio_trigger_ops at91_adc_trigger_ops = {
618	.set_trigger_state = &at91_adc_configure_trigger,
619};
620
621static struct iio_trigger *at91_adc_allocate_trigger(struct iio_dev *idev,
622						     const struct at91_adc_trigger *trigger)
623{
624	struct iio_trigger *trig;
625	int ret;
626
627	trig = iio_trigger_alloc(idev->dev.parent, "%s-dev%d-%s", idev->name,
628				 iio_device_id(idev), trigger->name);
629	if (trig == NULL)
630		return NULL;
631
632	iio_trigger_set_drvdata(trig, idev);
633	trig->ops = &at91_adc_trigger_ops;
634
635	ret = iio_trigger_register(trig);
636	if (ret) {
637		iio_trigger_free(trig);
638		return NULL;
639	}
640
641	return trig;
642}
643
644static int at91_adc_trigger_init(struct iio_dev *idev)
645{
646	struct at91_adc_state *st = iio_priv(idev);
647	int i, ret;
648
649	st->trig = devm_kcalloc(&idev->dev,
650				st->caps->trigger_number, sizeof(*st->trig),
651				GFP_KERNEL);
652
653	if (st->trig == NULL) {
654		ret = -ENOMEM;
655		goto error_ret;
656	}
657
658	for (i = 0; i < st->caps->trigger_number; i++) {
659		if (st->caps->triggers[i].is_external && !(st->use_external))
660			continue;
661
662		st->trig[i] = at91_adc_allocate_trigger(idev,
663							st->caps->triggers + i);
664		if (st->trig[i] == NULL) {
665			dev_err(&idev->dev,
666				"Could not allocate trigger %d\n", i);
667			ret = -ENOMEM;
668			goto error_trigger;
669		}
670	}
671
672	return 0;
673
674error_trigger:
675	for (i--; i >= 0; i--) {
676		iio_trigger_unregister(st->trig[i]);
677		iio_trigger_free(st->trig[i]);
678	}
679error_ret:
680	return ret;
681}
682
683static void at91_adc_trigger_remove(struct iio_dev *idev)
684{
685	struct at91_adc_state *st = iio_priv(idev);
686	int i;
687
688	for (i = 0; i < st->caps->trigger_number; i++) {
689		iio_trigger_unregister(st->trig[i]);
690		iio_trigger_free(st->trig[i]);
691	}
692}
693
694static int at91_adc_buffer_init(struct iio_dev *idev)
695{
696	return iio_triggered_buffer_setup(idev, &iio_pollfunc_store_time,
697		&at91_adc_trigger_handler, NULL);
698}
699
700static void at91_adc_buffer_remove(struct iio_dev *idev)
701{
702	iio_triggered_buffer_cleanup(idev);
703}
704
705static int at91_adc_read_raw(struct iio_dev *idev,
706			     struct iio_chan_spec const *chan,
707			     int *val, int *val2, long mask)
708{
709	struct at91_adc_state *st = iio_priv(idev);
710	int ret;
711
712	switch (mask) {
713	case IIO_CHAN_INFO_RAW:
714		mutex_lock(&st->lock);
715
716		st->chnb = chan->channel;
717		at91_adc_writel(st, AT91_ADC_CHER,
718				AT91_ADC_CH(chan->channel));
719		at91_adc_writel(st, AT91_ADC_IER, BIT(chan->channel));
720		at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_START);
721
722		ret = wait_event_interruptible_timeout(st->wq_data_avail,
723						       st->done,
724						       msecs_to_jiffies(1000));
725
726		/* Disable interrupts, regardless if adc conversion was
727		 * successful or not
728		 */
729		at91_adc_writel(st, AT91_ADC_CHDR,
730				AT91_ADC_CH(chan->channel));
731		at91_adc_writel(st, AT91_ADC_IDR, BIT(chan->channel));
732
733		if (ret > 0) {
734			/* a valid conversion took place */
735			*val = st->last_value;
736			st->last_value = 0;
737			st->done = false;
738			ret = IIO_VAL_INT;
739		} else if (ret == 0) {
740			/* conversion timeout */
741			dev_err(&idev->dev, "ADC Channel %d timeout.\n",
742				chan->channel);
743			ret = -ETIMEDOUT;
744		}
745
746		mutex_unlock(&st->lock);
747		return ret;
748
749	case IIO_CHAN_INFO_SCALE:
750		*val = st->vref_mv;
751		*val2 = chan->scan_type.realbits;
752		return IIO_VAL_FRACTIONAL_LOG2;
753	default:
754		break;
755	}
756	return -EINVAL;
757}
758
759
760static u32 calc_startup_ticks_9260(u32 startup_time, u32 adc_clk_khz)
761{
762	/*
763	 * Number of ticks needed to cover the startup time of the ADC
764	 * as defined in the electrical characteristics of the board,
765	 * divided by 8. The formula thus is :
766	 *   Startup Time = (ticks + 1) * 8 / ADC Clock
767	 */
768	return round_up((startup_time * adc_clk_khz / 1000) - 1, 8) / 8;
769}
770
771static u32 calc_startup_ticks_9x5(u32 startup_time, u32 adc_clk_khz)
772{
773	/*
774	 * For sama5d3x and at91sam9x5, the formula changes to:
775	 * Startup Time = <lookup_table_value> / ADC Clock
776	 */
777	static const int startup_lookup[] = {
778		0,   8,   16,  24,
779		64,  80,  96,  112,
780		512, 576, 640, 704,
781		768, 832, 896, 960
782		};
783	int i, size = ARRAY_SIZE(startup_lookup);
784	unsigned int ticks;
785
786	ticks = startup_time * adc_clk_khz / 1000;
787	for (i = 0; i < size; i++)
788		if (ticks < startup_lookup[i])
789			break;
790
791	ticks = i;
792	if (ticks == size)
793		/* Reach the end of lookup table */
794		ticks = size - 1;
795
796	return ticks;
797}
798
799static int at91_adc_probe_dt_ts(struct device_node *node,
800	struct at91_adc_state *st, struct device *dev)
801{
802	int ret;
803	u32 prop;
804
805	ret = of_property_read_u32(node, "atmel,adc-ts-wires", &prop);
806	if (ret) {
807		dev_info(dev, "ADC Touch screen is disabled.\n");
808		return 0;
809	}
810
811	switch (prop) {
812	case 4:
813	case 5:
814		st->touchscreen_type = prop;
815		break;
816	default:
817		dev_err(dev, "Unsupported number of touchscreen wires (%d). Should be 4 or 5.\n", prop);
818		return -EINVAL;
819	}
820
821	if (!st->caps->has_tsmr)
822		return 0;
823	prop = 0;
824	of_property_read_u32(node, "atmel,adc-ts-pressure-threshold", &prop);
825	st->ts_pressure_threshold = prop;
826	if (st->ts_pressure_threshold) {
827		return 0;
828	} else {
829		dev_err(dev, "Invalid pressure threshold for the touchscreen\n");
830		return -EINVAL;
831	}
832}
833
834static const struct iio_info at91_adc_info = {
835	.read_raw = &at91_adc_read_raw,
836};
837
838/* Touchscreen related functions */
839static int atmel_ts_open(struct input_dev *dev)
840{
841	struct at91_adc_state *st = input_get_drvdata(dev);
842
843	if (st->caps->has_tsmr)
844		at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_PEN);
845	else
846		at91_adc_writel(st, AT91_ADC_IER, AT91RL_ADC_IER_PEN);
847	return 0;
848}
849
850static void atmel_ts_close(struct input_dev *dev)
851{
852	struct at91_adc_state *st = input_get_drvdata(dev);
853
854	if (st->caps->has_tsmr)
855		at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_PEN);
856	else
857		at91_adc_writel(st, AT91_ADC_IDR, AT91RL_ADC_IER_PEN);
858}
859
860static int at91_ts_hw_init(struct iio_dev *idev, u32 adc_clk_khz)
861{
862	struct at91_adc_state *st = iio_priv(idev);
863	u32 reg = 0;
864	u32 tssctim = 0;
865	int i = 0;
866
867	/* a Pen Detect Debounce Time is necessary for the ADC Touch to avoid
868	 * pen detect noise.
869	 * The formula is : Pen Detect Debounce Time = (2 ^ pendbc) / ADCClock
870	 */
871	st->ts_pendbc = round_up(TOUCH_PEN_DETECT_DEBOUNCE_US * adc_clk_khz /
872				 1000, 1);
873
874	while (st->ts_pendbc >> ++i)
875		;	/* Empty! Find the shift offset */
876	if (abs(st->ts_pendbc - (1 << i)) < abs(st->ts_pendbc - (1 << (i - 1))))
877		st->ts_pendbc = i;
878	else
879		st->ts_pendbc = i - 1;
880
881	if (!st->caps->has_tsmr) {
882		reg = at91_adc_readl(st, AT91_ADC_MR);
883		reg |= AT91_ADC_TSAMOD_TS_ONLY_MODE | AT91_ADC_PENDET;
884
885		reg |= AT91_ADC_PENDBC_(st->ts_pendbc) & AT91_ADC_PENDBC;
886		at91_adc_writel(st, AT91_ADC_MR, reg);
887
888		reg = AT91_ADC_TSR_SHTIM_(TOUCH_SHTIM) & AT91_ADC_TSR_SHTIM;
889		at91_adc_writel(st, AT91_ADC_TSR, reg);
890
891		st->ts_sample_period_val = round_up((TOUCH_SAMPLE_PERIOD_US_RL *
892						    adc_clk_khz / 1000) - 1, 1);
893
894		return 0;
895	}
896
897	/* Touchscreen Switches Closure time needed for allowing the value to
898	 * stabilize.
899	 * Switch Closure Time = (TSSCTIM * 4) ADCClock periods
900	 */
901	tssctim = DIV_ROUND_UP(TOUCH_SCTIM_US * adc_clk_khz / 1000, 4);
902	dev_dbg(&idev->dev, "adc_clk at: %d KHz, tssctim at: %d\n",
903		adc_clk_khz, tssctim);
904
905	if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_4WIRE)
906		reg = AT91_ADC_TSMR_TSMODE_4WIRE_PRESS;
907	else
908		reg = AT91_ADC_TSMR_TSMODE_5WIRE;
909
910	reg |= AT91_ADC_TSMR_SCTIM_(tssctim) & AT91_ADC_TSMR_SCTIM;
911	reg |= AT91_ADC_TSMR_TSAV_(st->caps->ts_filter_average)
912	       & AT91_ADC_TSMR_TSAV;
913	reg |= AT91_ADC_TSMR_PENDBC_(st->ts_pendbc) & AT91_ADC_TSMR_PENDBC;
914	reg |= AT91_ADC_TSMR_NOTSDMA;
915	reg |= AT91_ADC_TSMR_PENDET_ENA;
916	reg |= 0x03 << 8;	/* TSFREQ, needs to be bigger than TSAV */
917
918	at91_adc_writel(st, AT91_ADC_TSMR, reg);
919
920	/* Change adc internal resistor value for better pen detection,
921	 * default value is 100 kOhm.
922	 * 0 = 200 kOhm, 1 = 150 kOhm, 2 = 100 kOhm, 3 = 50 kOhm
923	 * option only available on ES2 and higher
924	 */
925	at91_adc_writel(st, AT91_ADC_ACR, st->caps->ts_pen_detect_sensitivity
926			& AT91_ADC_ACR_PENDETSENS);
927
928	/* Sample Period Time = (TRGPER + 1) / ADCClock */
929	st->ts_sample_period_val = round_up((TOUCH_SAMPLE_PERIOD_US *
930			adc_clk_khz / 1000) - 1, 1);
931
932	return 0;
933}
934
935static int at91_ts_register(struct iio_dev *idev,
936		struct platform_device *pdev)
937{
938	struct at91_adc_state *st = iio_priv(idev);
939	struct input_dev *input;
940	int ret;
941
942	input = input_allocate_device();
943	if (!input) {
944		dev_err(&idev->dev, "Failed to allocate TS device!\n");
945		return -ENOMEM;
946	}
947
948	input->name = DRIVER_NAME;
949	input->id.bustype = BUS_HOST;
950	input->dev.parent = &pdev->dev;
951	input->open = atmel_ts_open;
952	input->close = atmel_ts_close;
953
954	__set_bit(EV_ABS, input->evbit);
955	__set_bit(EV_KEY, input->evbit);
956	__set_bit(BTN_TOUCH, input->keybit);
957	if (st->caps->has_tsmr) {
958		input_set_abs_params(input, ABS_X, 0, (1 << MAX_POS_BITS) - 1,
959				     0, 0);
960		input_set_abs_params(input, ABS_Y, 0, (1 << MAX_POS_BITS) - 1,
961				     0, 0);
962		input_set_abs_params(input, ABS_PRESSURE, 0, 0xffffff, 0, 0);
963	} else {
964		if (st->touchscreen_type != ATMEL_ADC_TOUCHSCREEN_4WIRE) {
965			dev_err(&pdev->dev,
966				"This touchscreen controller only support 4 wires\n");
967			ret = -EINVAL;
968			goto err;
969		}
970
971		input_set_abs_params(input, ABS_X, 0, (1 << MAX_RLPOS_BITS) - 1,
972				     0, 0);
973		input_set_abs_params(input, ABS_Y, 0, (1 << MAX_RLPOS_BITS) - 1,
974				     0, 0);
975	}
976
977	st->ts_input = input;
978	input_set_drvdata(input, st);
979
980	ret = input_register_device(input);
981	if (ret)
982		goto err;
983
984	return ret;
985
986err:
987	input_free_device(st->ts_input);
988	return ret;
989}
990
991static void at91_ts_unregister(struct at91_adc_state *st)
992{
993	input_unregister_device(st->ts_input);
994}
995
996static int at91_adc_probe(struct platform_device *pdev)
997{
998	unsigned int prsc, mstrclk, ticks, adc_clk, adc_clk_khz, shtim;
999	struct device_node *node = pdev->dev.of_node;
1000	int ret;
1001	struct iio_dev *idev;
1002	struct at91_adc_state *st;
1003	u32 reg, prop;
1004	char *s;
1005
1006	idev = devm_iio_device_alloc(&pdev->dev, sizeof(struct at91_adc_state));
1007	if (!idev)
1008		return -ENOMEM;
1009
1010	st = iio_priv(idev);
1011
1012	st->caps = of_device_get_match_data(&pdev->dev);
1013
1014	st->use_external = of_property_read_bool(node, "atmel,adc-use-external-triggers");
1015
1016	if (of_property_read_u32(node, "atmel,adc-channels-used", &prop))
1017		return dev_err_probe(&idev->dev, -EINVAL,
1018				     "Missing adc-channels-used property in the DT.\n");
1019	st->channels_mask = prop;
1020
1021	st->sleep_mode = of_property_read_bool(node, "atmel,adc-sleep-mode");
1022
1023	if (of_property_read_u32(node, "atmel,adc-startup-time", &prop))
1024		return dev_err_probe(&idev->dev, -EINVAL,
1025				     "Missing adc-startup-time property in the DT.\n");
1026	st->startup_time = prop;
1027
1028	prop = 0;
1029	of_property_read_u32(node, "atmel,adc-sample-hold-time", &prop);
1030	st->sample_hold_time = prop;
1031
1032	if (of_property_read_u32(node, "atmel,adc-vref", &prop))
1033		return dev_err_probe(&idev->dev, -EINVAL,
1034				     "Missing adc-vref property in the DT.\n");
1035	st->vref_mv = prop;
1036
1037	st->res = st->caps->high_res_bits;
1038	if (st->caps->low_res_bits &&
1039	    !of_property_read_string(node, "atmel,adc-use-res", (const char **)&s)
1040	    && !strcmp(s, "lowres"))
1041		st->res = st->caps->low_res_bits;
1042
1043	dev_info(&idev->dev, "Resolution used: %u bits\n", st->res);
1044
1045	st->registers = &st->caps->registers;
1046	st->num_channels = st->caps->num_channels;
1047
1048	/* Check if touchscreen is supported. */
1049	if (st->caps->has_ts) {
1050		ret = at91_adc_probe_dt_ts(node, st, &idev->dev);
1051		if (ret)
1052			return ret;
1053	}
1054
1055	platform_set_drvdata(pdev, idev);
1056
1057	idev->name = dev_name(&pdev->dev);
1058	idev->modes = INDIO_DIRECT_MODE;
1059	idev->info = &at91_adc_info;
1060
1061	st->irq = platform_get_irq(pdev, 0);
1062	if (st->irq < 0)
1063		return -ENODEV;
1064
1065	st->reg_base = devm_platform_ioremap_resource(pdev, 0);
1066	if (IS_ERR(st->reg_base))
1067		return PTR_ERR(st->reg_base);
1068
1069	/*
1070	 * Disable all IRQs before setting up the handler
1071	 */
1072	at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_SWRST);
1073	at91_adc_writel(st, AT91_ADC_IDR, 0xFFFFFFFF);
1074
1075	if (st->caps->has_tsmr)
1076		ret = devm_request_irq(&pdev->dev, st->irq,
1077				       at91_adc_9x5_interrupt, 0,
1078				       pdev->dev.driver->name, idev);
1079	else
1080		ret = devm_request_irq(&pdev->dev, st->irq,
1081				       at91_adc_rl_interrupt, 0,
1082				       pdev->dev.driver->name, idev);
1083	if (ret)
1084		return dev_err_probe(&pdev->dev, ret,
1085				     "Failed to allocate IRQ.\n");
1086
1087	st->clk = devm_clk_get_enabled(&pdev->dev, "adc_clk");
1088	if (IS_ERR(st->clk))
1089		return dev_err_probe(&pdev->dev, PTR_ERR(st->clk),
1090				     "Could not prepare or enable the clock.\n");
1091
1092	st->adc_clk = devm_clk_get_enabled(&pdev->dev, "adc_op_clk");
1093	if (IS_ERR(st->adc_clk))
1094		return dev_err_probe(&pdev->dev, PTR_ERR(st->adc_clk),
1095				     "Could not prepare or enable the ADC clock.\n");
1096
1097	/*
1098	 * Prescaler rate computation using the formula from the Atmel's
1099	 * datasheet : ADC Clock = MCK / ((Prescaler + 1) * 2), ADC Clock being
1100	 * specified by the electrical characteristics of the board.
1101	 */
1102	mstrclk = clk_get_rate(st->clk);
1103	adc_clk = clk_get_rate(st->adc_clk);
1104	adc_clk_khz = adc_clk / 1000;
1105
1106	dev_dbg(&pdev->dev, "Master clock is set as: %d Hz, adc_clk should set as: %d Hz\n",
1107		mstrclk, adc_clk);
1108
1109	prsc = (mstrclk / (2 * adc_clk)) - 1;
1110
1111	if (!st->startup_time)
1112		return dev_err_probe(&pdev->dev, -EINVAL,
1113				     "No startup time available.\n");
1114	ticks = (*st->caps->calc_startup_ticks)(st->startup_time, adc_clk_khz);
1115
1116	/*
1117	 * a minimal Sample and Hold Time is necessary for the ADC to guarantee
1118	 * the best converted final value between two channels selection
1119	 * The formula thus is : Sample and Hold Time = (shtim + 1) / ADCClock
1120	 */
1121	if (st->sample_hold_time > 0)
1122		shtim = round_up((st->sample_hold_time * adc_clk_khz / 1000)
1123				 - 1, 1);
1124	else
1125		shtim = 0;
1126
1127	reg = AT91_ADC_PRESCAL_(prsc) & st->registers->mr_prescal_mask;
1128	reg |= AT91_ADC_STARTUP_(ticks) & st->registers->mr_startup_mask;
1129	if (st->res == st->caps->low_res_bits)
1130		reg |= AT91_ADC_LOWRES;
1131	if (st->sleep_mode)
1132		reg |= AT91_ADC_SLEEP;
1133	reg |= AT91_ADC_SHTIM_(shtim) & AT91_ADC_SHTIM;
1134	at91_adc_writel(st, AT91_ADC_MR, reg);
1135
1136	/* Setup the ADC channels available on the board */
1137	ret = at91_adc_channel_init(idev);
1138	if (ret < 0)
1139		return dev_err_probe(&pdev->dev, ret,
1140				     "Couldn't initialize the channels.\n");
1141
1142	init_waitqueue_head(&st->wq_data_avail);
1143	mutex_init(&st->lock);
1144
1145	/*
1146	 * Since touch screen will set trigger register as period trigger. So
1147	 * when touch screen is enabled, then we have to disable hardware
1148	 * trigger for classic adc.
1149	 */
1150	if (!st->touchscreen_type) {
1151		ret = at91_adc_buffer_init(idev);
1152		if (ret < 0)
1153			return dev_err_probe(&pdev->dev, ret,
1154					     "Couldn't initialize the buffer.\n");
1155
1156		ret = at91_adc_trigger_init(idev);
1157		if (ret < 0) {
1158			dev_err(&pdev->dev, "Couldn't setup the triggers.\n");
1159			at91_adc_buffer_remove(idev);
1160			return ret;
1161		}
1162	} else {
1163		ret = at91_ts_register(idev, pdev);
1164		if (ret)
1165			return ret;
1166
1167		at91_ts_hw_init(idev, adc_clk_khz);
1168	}
1169
1170	ret = iio_device_register(idev);
1171	if (ret < 0) {
1172		dev_err(&pdev->dev, "Couldn't register the device.\n");
1173		goto error_iio_device_register;
1174	}
1175
1176	return 0;
1177
1178error_iio_device_register:
1179	if (!st->touchscreen_type) {
1180		at91_adc_trigger_remove(idev);
1181		at91_adc_buffer_remove(idev);
1182	} else {
1183		at91_ts_unregister(st);
1184	}
1185	return ret;
1186}
1187
1188static void at91_adc_remove(struct platform_device *pdev)
1189{
1190	struct iio_dev *idev = platform_get_drvdata(pdev);
1191	struct at91_adc_state *st = iio_priv(idev);
1192
1193	iio_device_unregister(idev);
1194	if (!st->touchscreen_type) {
1195		at91_adc_trigger_remove(idev);
1196		at91_adc_buffer_remove(idev);
1197	} else {
1198		at91_ts_unregister(st);
1199	}
1200}
1201
1202static int at91_adc_suspend(struct device *dev)
1203{
1204	struct iio_dev *idev = dev_get_drvdata(dev);
1205	struct at91_adc_state *st = iio_priv(idev);
1206
1207	pinctrl_pm_select_sleep_state(dev);
1208	clk_disable_unprepare(st->clk);
1209
1210	return 0;
1211}
1212
1213static int at91_adc_resume(struct device *dev)
1214{
1215	struct iio_dev *idev = dev_get_drvdata(dev);
1216	struct at91_adc_state *st = iio_priv(idev);
1217
1218	clk_prepare_enable(st->clk);
1219	pinctrl_pm_select_default_state(dev);
1220
1221	return 0;
1222}
1223
1224static DEFINE_SIMPLE_DEV_PM_OPS(at91_adc_pm_ops, at91_adc_suspend,
1225				at91_adc_resume);
1226
1227static const struct at91_adc_trigger at91sam9260_triggers[] = {
1228	{ .name = "timer-counter-0", .value = 0x1 },
1229	{ .name = "timer-counter-1", .value = 0x3 },
1230	{ .name = "timer-counter-2", .value = 0x5 },
1231	{ .name = "external", .value = 0xd, .is_external = true },
1232};
1233
1234static struct at91_adc_caps at91sam9260_caps = {
1235	.calc_startup_ticks = calc_startup_ticks_9260,
1236	.num_channels = 4,
1237	.low_res_bits = 8,
1238	.high_res_bits = 10,
1239	.registers = {
1240		.channel_base = AT91_ADC_CHR(0),
1241		.drdy_mask = AT91_ADC_DRDY,
1242		.status_register = AT91_ADC_SR,
1243		.trigger_register = AT91_ADC_TRGR_9260,
1244		.mr_prescal_mask = AT91_ADC_PRESCAL_9260,
1245		.mr_startup_mask = AT91_ADC_STARTUP_9260,
1246	},
1247	.triggers = at91sam9260_triggers,
1248	.trigger_number = ARRAY_SIZE(at91sam9260_triggers),
1249};
1250
1251static const struct at91_adc_trigger at91sam9x5_triggers[] = {
1252	{ .name = "external-rising", .value = 0x1, .is_external = true },
1253	{ .name = "external-falling", .value = 0x2, .is_external = true },
1254	{ .name = "external-any", .value = 0x3, .is_external = true },
1255	{ .name = "continuous", .value = 0x6 },
1256};
1257
1258static struct at91_adc_caps at91sam9rl_caps = {
1259	.has_ts = true,
1260	.calc_startup_ticks = calc_startup_ticks_9260,	/* same as 9260 */
1261	.num_channels = 6,
1262	.low_res_bits = 8,
1263	.high_res_bits = 10,
1264	.registers = {
1265		.channel_base = AT91_ADC_CHR(0),
1266		.drdy_mask = AT91_ADC_DRDY,
1267		.status_register = AT91_ADC_SR,
1268		.trigger_register = AT91_ADC_TRGR_9G45,
1269		.mr_prescal_mask = AT91_ADC_PRESCAL_9260,
1270		.mr_startup_mask = AT91_ADC_STARTUP_9G45,
1271	},
1272	.triggers = at91sam9x5_triggers,
1273	.trigger_number = ARRAY_SIZE(at91sam9x5_triggers),
1274};
1275
1276static struct at91_adc_caps at91sam9g45_caps = {
1277	.has_ts = true,
1278	.calc_startup_ticks = calc_startup_ticks_9260,	/* same as 9260 */
1279	.num_channels = 8,
1280	.low_res_bits = 8,
1281	.high_res_bits = 10,
1282	.registers = {
1283		.channel_base = AT91_ADC_CHR(0),
1284		.drdy_mask = AT91_ADC_DRDY,
1285		.status_register = AT91_ADC_SR,
1286		.trigger_register = AT91_ADC_TRGR_9G45,
1287		.mr_prescal_mask = AT91_ADC_PRESCAL_9G45,
1288		.mr_startup_mask = AT91_ADC_STARTUP_9G45,
1289	},
1290	.triggers = at91sam9x5_triggers,
1291	.trigger_number = ARRAY_SIZE(at91sam9x5_triggers),
1292};
1293
1294static struct at91_adc_caps at91sam9x5_caps = {
1295	.has_ts = true,
1296	.has_tsmr = true,
1297	.ts_filter_average = 3,
1298	.ts_pen_detect_sensitivity = 2,
1299	.calc_startup_ticks = calc_startup_ticks_9x5,
1300	.num_channels = 12,
1301	.low_res_bits = 8,
1302	.high_res_bits = 10,
1303	.registers = {
1304		.channel_base = AT91_ADC_CDR0_9X5,
1305		.drdy_mask = AT91_ADC_SR_DRDY_9X5,
1306		.status_register = AT91_ADC_SR_9X5,
1307		.trigger_register = AT91_ADC_TRGR_9X5,
1308		/* prescal mask is same as 9G45 */
1309		.mr_prescal_mask = AT91_ADC_PRESCAL_9G45,
1310		.mr_startup_mask = AT91_ADC_STARTUP_9X5,
1311	},
1312	.triggers = at91sam9x5_triggers,
1313	.trigger_number = ARRAY_SIZE(at91sam9x5_triggers),
1314};
1315
1316static struct at91_adc_caps sama5d3_caps = {
1317	.has_ts = true,
1318	.has_tsmr = true,
1319	.ts_filter_average = 3,
1320	.ts_pen_detect_sensitivity = 2,
1321	.calc_startup_ticks = calc_startup_ticks_9x5,
1322	.num_channels = 12,
1323	.low_res_bits = 0,
1324	.high_res_bits = 12,
1325	.registers = {
1326		.channel_base = AT91_ADC_CDR0_9X5,
1327		.drdy_mask = AT91_ADC_SR_DRDY_9X5,
1328		.status_register = AT91_ADC_SR_9X5,
1329		.trigger_register = AT91_ADC_TRGR_9X5,
1330		.mr_prescal_mask = AT91_ADC_PRESCAL_9G45,
1331		.mr_startup_mask = AT91_ADC_STARTUP_9X5,
1332	},
1333	.triggers = at91sam9x5_triggers,
1334	.trigger_number = ARRAY_SIZE(at91sam9x5_triggers),
1335};
1336
1337static const struct of_device_id at91_adc_dt_ids[] = {
1338	{ .compatible = "atmel,at91sam9260-adc", .data = &at91sam9260_caps },
1339	{ .compatible = "atmel,at91sam9rl-adc", .data = &at91sam9rl_caps },
1340	{ .compatible = "atmel,at91sam9g45-adc", .data = &at91sam9g45_caps },
1341	{ .compatible = "atmel,at91sam9x5-adc", .data = &at91sam9x5_caps },
1342	{ .compatible = "atmel,sama5d3-adc", .data = &sama5d3_caps },
1343	{},
1344};
1345MODULE_DEVICE_TABLE(of, at91_adc_dt_ids);
1346
1347static struct platform_driver at91_adc_driver = {
1348	.probe = at91_adc_probe,
1349	.remove_new = at91_adc_remove,
1350	.driver = {
1351		   .name = DRIVER_NAME,
1352		   .of_match_table = at91_adc_dt_ids,
1353		   .pm = pm_sleep_ptr(&at91_adc_pm_ops),
1354	},
1355};
1356
1357module_platform_driver(at91_adc_driver);
1358
1359MODULE_LICENSE("GPL");
1360MODULE_DESCRIPTION("Atmel AT91 ADC Driver");
1361MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
1362