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