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
153 enum 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 */
166 struct 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 */
182 struct 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
191 struct 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
214 struct 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
at91_adc_trigger_handler(int irq,void * p)263 static 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 */
handle_adc_eoc_trigger(int irq,struct iio_dev * idev)292 static 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
at91_ts_sample(struct iio_dev * idev)308 static 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
at91_adc_rl_interrupt(int irq,void * private)371 static 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
at91_adc_9x5_interrupt(int irq,void * private)436 static 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
at91_adc_channel_init(struct iio_dev * idev)484 static 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
at91_adc_get_trigger_value_by_name(struct iio_dev * idev,const struct at91_adc_trigger * triggers,const char * trigger_name)538 static 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
at91_adc_configure_trigger(struct iio_trigger * trig,bool state)567 static 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
617 static const struct iio_trigger_ops at91_adc_trigger_ops = {
618 .set_trigger_state = &at91_adc_configure_trigger,
619 };
620
at91_adc_allocate_trigger(struct iio_dev * idev,const struct at91_adc_trigger * trigger)621 static 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
at91_adc_trigger_init(struct iio_dev * idev)644 static 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
674 error_trigger:
675 for (i--; i >= 0; i--) {
676 iio_trigger_unregister(st->trig[i]);
677 iio_trigger_free(st->trig[i]);
678 }
679 error_ret:
680 return ret;
681 }
682
at91_adc_trigger_remove(struct iio_dev * idev)683 static 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
at91_adc_buffer_init(struct iio_dev * idev)694 static 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
at91_adc_buffer_remove(struct iio_dev * idev)700 static void at91_adc_buffer_remove(struct iio_dev *idev)
701 {
702 iio_triggered_buffer_cleanup(idev);
703 }
704
at91_adc_read_raw(struct iio_dev * idev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)705 static 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
calc_startup_ticks_9260(u32 startup_time,u32 adc_clk_khz)760 static 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
calc_startup_ticks_9x5(u32 startup_time,u32 adc_clk_khz)771 static 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
at91_adc_probe_dt_ts(struct device_node * node,struct at91_adc_state * st,struct device * dev)799 static 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
834 static const struct iio_info at91_adc_info = {
835 .read_raw = &at91_adc_read_raw,
836 };
837
838 /* Touchscreen related functions */
atmel_ts_open(struct input_dev * dev)839 static 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
atmel_ts_close(struct input_dev * dev)850 static 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
at91_ts_hw_init(struct iio_dev * idev,u32 adc_clk_khz)860 static 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
at91_ts_register(struct iio_dev * idev,struct platform_device * pdev)935 static 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
986 err:
987 input_free_device(st->ts_input);
988 return ret;
989 }
990
at91_ts_unregister(struct at91_adc_state * st)991 static void at91_ts_unregister(struct at91_adc_state *st)
992 {
993 input_unregister_device(st->ts_input);
994 }
995
at91_adc_probe(struct platform_device * pdev)996 static 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 dev_err(&idev->dev, "Missing adc-channels-used property in the DT.\n");
1018 return -EINVAL;
1019 }
1020 st->channels_mask = prop;
1021
1022 st->sleep_mode = of_property_read_bool(node, "atmel,adc-sleep-mode");
1023
1024 if (of_property_read_u32(node, "atmel,adc-startup-time", &prop)) {
1025 dev_err(&idev->dev, "Missing adc-startup-time property in the DT.\n");
1026 return -EINVAL;
1027 }
1028 st->startup_time = prop;
1029
1030 prop = 0;
1031 of_property_read_u32(node, "atmel,adc-sample-hold-time", &prop);
1032 st->sample_hold_time = prop;
1033
1034 if (of_property_read_u32(node, "atmel,adc-vref", &prop)) {
1035 dev_err(&idev->dev, "Missing adc-vref property in the DT.\n");
1036 return -EINVAL;
1037 }
1038 st->vref_mv = prop;
1039
1040 st->res = st->caps->high_res_bits;
1041 if (st->caps->low_res_bits &&
1042 !of_property_read_string(node, "atmel,adc-use-res", (const char **)&s)
1043 && !strcmp(s, "lowres"))
1044 st->res = st->caps->low_res_bits;
1045
1046 dev_info(&idev->dev, "Resolution used: %u bits\n", st->res);
1047
1048 st->registers = &st->caps->registers;
1049 st->num_channels = st->caps->num_channels;
1050
1051 /* Check if touchscreen is supported. */
1052 if (st->caps->has_ts) {
1053 ret = at91_adc_probe_dt_ts(node, st, &idev->dev);
1054 if (ret)
1055 return ret;
1056 }
1057
1058 platform_set_drvdata(pdev, idev);
1059
1060 idev->name = dev_name(&pdev->dev);
1061 idev->modes = INDIO_DIRECT_MODE;
1062 idev->info = &at91_adc_info;
1063
1064 st->irq = platform_get_irq(pdev, 0);
1065 if (st->irq < 0)
1066 return -ENODEV;
1067
1068 st->reg_base = devm_platform_ioremap_resource(pdev, 0);
1069 if (IS_ERR(st->reg_base))
1070 return PTR_ERR(st->reg_base);
1071
1072
1073 /*
1074 * Disable all IRQs before setting up the handler
1075 */
1076 at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_SWRST);
1077 at91_adc_writel(st, AT91_ADC_IDR, 0xFFFFFFFF);
1078
1079 if (st->caps->has_tsmr)
1080 ret = request_irq(st->irq, at91_adc_9x5_interrupt, 0,
1081 pdev->dev.driver->name, idev);
1082 else
1083 ret = request_irq(st->irq, at91_adc_rl_interrupt, 0,
1084 pdev->dev.driver->name, idev);
1085 if (ret) {
1086 dev_err(&pdev->dev, "Failed to allocate IRQ.\n");
1087 return ret;
1088 }
1089
1090 st->clk = devm_clk_get(&pdev->dev, "adc_clk");
1091 if (IS_ERR(st->clk)) {
1092 dev_err(&pdev->dev, "Failed to get the clock.\n");
1093 ret = PTR_ERR(st->clk);
1094 goto error_free_irq;
1095 }
1096
1097 ret = clk_prepare_enable(st->clk);
1098 if (ret) {
1099 dev_err(&pdev->dev,
1100 "Could not prepare or enable the clock.\n");
1101 goto error_free_irq;
1102 }
1103
1104 st->adc_clk = devm_clk_get(&pdev->dev, "adc_op_clk");
1105 if (IS_ERR(st->adc_clk)) {
1106 dev_err(&pdev->dev, "Failed to get the ADC clock.\n");
1107 ret = PTR_ERR(st->adc_clk);
1108 goto error_disable_clk;
1109 }
1110
1111 ret = clk_prepare_enable(st->adc_clk);
1112 if (ret) {
1113 dev_err(&pdev->dev,
1114 "Could not prepare or enable the ADC clock.\n");
1115 goto error_disable_clk;
1116 }
1117
1118 /*
1119 * Prescaler rate computation using the formula from the Atmel's
1120 * datasheet : ADC Clock = MCK / ((Prescaler + 1) * 2), ADC Clock being
1121 * specified by the electrical characteristics of the board.
1122 */
1123 mstrclk = clk_get_rate(st->clk);
1124 adc_clk = clk_get_rate(st->adc_clk);
1125 adc_clk_khz = adc_clk / 1000;
1126
1127 dev_dbg(&pdev->dev, "Master clock is set as: %d Hz, adc_clk should set as: %d Hz\n",
1128 mstrclk, adc_clk);
1129
1130 prsc = (mstrclk / (2 * adc_clk)) - 1;
1131
1132 if (!st->startup_time) {
1133 dev_err(&pdev->dev, "No startup time available.\n");
1134 ret = -EINVAL;
1135 goto error_disable_adc_clk;
1136 }
1137 ticks = (*st->caps->calc_startup_ticks)(st->startup_time, adc_clk_khz);
1138
1139 /*
1140 * a minimal Sample and Hold Time is necessary for the ADC to guarantee
1141 * the best converted final value between two channels selection
1142 * The formula thus is : Sample and Hold Time = (shtim + 1) / ADCClock
1143 */
1144 if (st->sample_hold_time > 0)
1145 shtim = round_up((st->sample_hold_time * adc_clk_khz / 1000)
1146 - 1, 1);
1147 else
1148 shtim = 0;
1149
1150 reg = AT91_ADC_PRESCAL_(prsc) & st->registers->mr_prescal_mask;
1151 reg |= AT91_ADC_STARTUP_(ticks) & st->registers->mr_startup_mask;
1152 if (st->res == st->caps->low_res_bits)
1153 reg |= AT91_ADC_LOWRES;
1154 if (st->sleep_mode)
1155 reg |= AT91_ADC_SLEEP;
1156 reg |= AT91_ADC_SHTIM_(shtim) & AT91_ADC_SHTIM;
1157 at91_adc_writel(st, AT91_ADC_MR, reg);
1158
1159 /* Setup the ADC channels available on the board */
1160 ret = at91_adc_channel_init(idev);
1161 if (ret < 0) {
1162 dev_err(&pdev->dev, "Couldn't initialize the channels.\n");
1163 goto error_disable_adc_clk;
1164 }
1165
1166 init_waitqueue_head(&st->wq_data_avail);
1167 mutex_init(&st->lock);
1168
1169 /*
1170 * Since touch screen will set trigger register as period trigger. So
1171 * when touch screen is enabled, then we have to disable hardware
1172 * trigger for classic adc.
1173 */
1174 if (!st->touchscreen_type) {
1175 ret = at91_adc_buffer_init(idev);
1176 if (ret < 0) {
1177 dev_err(&pdev->dev, "Couldn't initialize the buffer.\n");
1178 goto error_disable_adc_clk;
1179 }
1180
1181 ret = at91_adc_trigger_init(idev);
1182 if (ret < 0) {
1183 dev_err(&pdev->dev, "Couldn't setup the triggers.\n");
1184 at91_adc_buffer_remove(idev);
1185 goto error_disable_adc_clk;
1186 }
1187 } else {
1188 ret = at91_ts_register(idev, pdev);
1189 if (ret)
1190 goto error_disable_adc_clk;
1191
1192 at91_ts_hw_init(idev, adc_clk_khz);
1193 }
1194
1195 ret = iio_device_register(idev);
1196 if (ret < 0) {
1197 dev_err(&pdev->dev, "Couldn't register the device.\n");
1198 goto error_iio_device_register;
1199 }
1200
1201 return 0;
1202
1203 error_iio_device_register:
1204 if (!st->touchscreen_type) {
1205 at91_adc_trigger_remove(idev);
1206 at91_adc_buffer_remove(idev);
1207 } else {
1208 at91_ts_unregister(st);
1209 }
1210 error_disable_adc_clk:
1211 clk_disable_unprepare(st->adc_clk);
1212 error_disable_clk:
1213 clk_disable_unprepare(st->clk);
1214 error_free_irq:
1215 free_irq(st->irq, idev);
1216 return ret;
1217 }
1218
at91_adc_remove(struct platform_device * pdev)1219 static int at91_adc_remove(struct platform_device *pdev)
1220 {
1221 struct iio_dev *idev = platform_get_drvdata(pdev);
1222 struct at91_adc_state *st = iio_priv(idev);
1223
1224 iio_device_unregister(idev);
1225 if (!st->touchscreen_type) {
1226 at91_adc_trigger_remove(idev);
1227 at91_adc_buffer_remove(idev);
1228 } else {
1229 at91_ts_unregister(st);
1230 }
1231 clk_disable_unprepare(st->adc_clk);
1232 clk_disable_unprepare(st->clk);
1233 free_irq(st->irq, idev);
1234
1235 return 0;
1236 }
1237
at91_adc_suspend(struct device * dev)1238 static int at91_adc_suspend(struct device *dev)
1239 {
1240 struct iio_dev *idev = dev_get_drvdata(dev);
1241 struct at91_adc_state *st = iio_priv(idev);
1242
1243 pinctrl_pm_select_sleep_state(dev);
1244 clk_disable_unprepare(st->clk);
1245
1246 return 0;
1247 }
1248
at91_adc_resume(struct device * dev)1249 static int at91_adc_resume(struct device *dev)
1250 {
1251 struct iio_dev *idev = dev_get_drvdata(dev);
1252 struct at91_adc_state *st = iio_priv(idev);
1253
1254 clk_prepare_enable(st->clk);
1255 pinctrl_pm_select_default_state(dev);
1256
1257 return 0;
1258 }
1259
1260 static DEFINE_SIMPLE_DEV_PM_OPS(at91_adc_pm_ops, at91_adc_suspend,
1261 at91_adc_resume);
1262
1263 static const struct at91_adc_trigger at91sam9260_triggers[] = {
1264 { .name = "timer-counter-0", .value = 0x1 },
1265 { .name = "timer-counter-1", .value = 0x3 },
1266 { .name = "timer-counter-2", .value = 0x5 },
1267 { .name = "external", .value = 0xd, .is_external = true },
1268 };
1269
1270 static struct at91_adc_caps at91sam9260_caps = {
1271 .calc_startup_ticks = calc_startup_ticks_9260,
1272 .num_channels = 4,
1273 .low_res_bits = 8,
1274 .high_res_bits = 10,
1275 .registers = {
1276 .channel_base = AT91_ADC_CHR(0),
1277 .drdy_mask = AT91_ADC_DRDY,
1278 .status_register = AT91_ADC_SR,
1279 .trigger_register = AT91_ADC_TRGR_9260,
1280 .mr_prescal_mask = AT91_ADC_PRESCAL_9260,
1281 .mr_startup_mask = AT91_ADC_STARTUP_9260,
1282 },
1283 .triggers = at91sam9260_triggers,
1284 .trigger_number = ARRAY_SIZE(at91sam9260_triggers),
1285 };
1286
1287 static const struct at91_adc_trigger at91sam9x5_triggers[] = {
1288 { .name = "external-rising", .value = 0x1, .is_external = true },
1289 { .name = "external-falling", .value = 0x2, .is_external = true },
1290 { .name = "external-any", .value = 0x3, .is_external = true },
1291 { .name = "continuous", .value = 0x6 },
1292 };
1293
1294 static struct at91_adc_caps at91sam9rl_caps = {
1295 .has_ts = true,
1296 .calc_startup_ticks = calc_startup_ticks_9260, /* same as 9260 */
1297 .num_channels = 6,
1298 .low_res_bits = 8,
1299 .high_res_bits = 10,
1300 .registers = {
1301 .channel_base = AT91_ADC_CHR(0),
1302 .drdy_mask = AT91_ADC_DRDY,
1303 .status_register = AT91_ADC_SR,
1304 .trigger_register = AT91_ADC_TRGR_9G45,
1305 .mr_prescal_mask = AT91_ADC_PRESCAL_9260,
1306 .mr_startup_mask = AT91_ADC_STARTUP_9G45,
1307 },
1308 .triggers = at91sam9x5_triggers,
1309 .trigger_number = ARRAY_SIZE(at91sam9x5_triggers),
1310 };
1311
1312 static struct at91_adc_caps at91sam9g45_caps = {
1313 .has_ts = true,
1314 .calc_startup_ticks = calc_startup_ticks_9260, /* same as 9260 */
1315 .num_channels = 8,
1316 .low_res_bits = 8,
1317 .high_res_bits = 10,
1318 .registers = {
1319 .channel_base = AT91_ADC_CHR(0),
1320 .drdy_mask = AT91_ADC_DRDY,
1321 .status_register = AT91_ADC_SR,
1322 .trigger_register = AT91_ADC_TRGR_9G45,
1323 .mr_prescal_mask = AT91_ADC_PRESCAL_9G45,
1324 .mr_startup_mask = AT91_ADC_STARTUP_9G45,
1325 },
1326 .triggers = at91sam9x5_triggers,
1327 .trigger_number = ARRAY_SIZE(at91sam9x5_triggers),
1328 };
1329
1330 static struct at91_adc_caps at91sam9x5_caps = {
1331 .has_ts = true,
1332 .has_tsmr = true,
1333 .ts_filter_average = 3,
1334 .ts_pen_detect_sensitivity = 2,
1335 .calc_startup_ticks = calc_startup_ticks_9x5,
1336 .num_channels = 12,
1337 .low_res_bits = 8,
1338 .high_res_bits = 10,
1339 .registers = {
1340 .channel_base = AT91_ADC_CDR0_9X5,
1341 .drdy_mask = AT91_ADC_SR_DRDY_9X5,
1342 .status_register = AT91_ADC_SR_9X5,
1343 .trigger_register = AT91_ADC_TRGR_9X5,
1344 /* prescal mask is same as 9G45 */
1345 .mr_prescal_mask = AT91_ADC_PRESCAL_9G45,
1346 .mr_startup_mask = AT91_ADC_STARTUP_9X5,
1347 },
1348 .triggers = at91sam9x5_triggers,
1349 .trigger_number = ARRAY_SIZE(at91sam9x5_triggers),
1350 };
1351
1352 static struct at91_adc_caps sama5d3_caps = {
1353 .has_ts = true,
1354 .has_tsmr = true,
1355 .ts_filter_average = 3,
1356 .ts_pen_detect_sensitivity = 2,
1357 .calc_startup_ticks = calc_startup_ticks_9x5,
1358 .num_channels = 12,
1359 .low_res_bits = 0,
1360 .high_res_bits = 12,
1361 .registers = {
1362 .channel_base = AT91_ADC_CDR0_9X5,
1363 .drdy_mask = AT91_ADC_SR_DRDY_9X5,
1364 .status_register = AT91_ADC_SR_9X5,
1365 .trigger_register = AT91_ADC_TRGR_9X5,
1366 .mr_prescal_mask = AT91_ADC_PRESCAL_9G45,
1367 .mr_startup_mask = AT91_ADC_STARTUP_9X5,
1368 },
1369 .triggers = at91sam9x5_triggers,
1370 .trigger_number = ARRAY_SIZE(at91sam9x5_triggers),
1371 };
1372
1373 static const struct of_device_id at91_adc_dt_ids[] = {
1374 { .compatible = "atmel,at91sam9260-adc", .data = &at91sam9260_caps },
1375 { .compatible = "atmel,at91sam9rl-adc", .data = &at91sam9rl_caps },
1376 { .compatible = "atmel,at91sam9g45-adc", .data = &at91sam9g45_caps },
1377 { .compatible = "atmel,at91sam9x5-adc", .data = &at91sam9x5_caps },
1378 { .compatible = "atmel,sama5d3-adc", .data = &sama5d3_caps },
1379 {},
1380 };
1381 MODULE_DEVICE_TABLE(of, at91_adc_dt_ids);
1382
1383 static struct platform_driver at91_adc_driver = {
1384 .probe = at91_adc_probe,
1385 .remove = at91_adc_remove,
1386 .driver = {
1387 .name = DRIVER_NAME,
1388 .of_match_table = at91_adc_dt_ids,
1389 .pm = pm_sleep_ptr(&at91_adc_pm_ops),
1390 },
1391 };
1392
1393 module_platform_driver(at91_adc_driver);
1394
1395 MODULE_LICENSE("GPL");
1396 MODULE_DESCRIPTION("Atmel AT91 ADC Driver");
1397 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
1398