?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / drivers / iio / adc / at91_adc.c
blobabe99856c823ab6250bbfdedea447dcb337389d3
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/of_device.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/platform_data/at91_adc.h>
26
27 #include <linux/iio/iio.h>
28 #include <linux/iio/buffer.h>
29 #include <linux/iio/trigger.h>
30 #include <linux/iio/trigger_consumer.h>
31 #include <linux/iio/triggered_buffer.h>
32 #include <linux/pinctrl/consumer.h>
33
34 /* Registers */
35 #define AT91_ADC_CR 0x00 /* Control Register */
36 #define AT91_ADC_SWRST (1 << 0) /* Software Reset */
37 #define AT91_ADC_START (1 << 1) /* Start Conversion */
38
39 #define AT91_ADC_MR 0x04 /* Mode Register */
40 #define AT91_ADC_TSAMOD (3 << 0) /* ADC mode */
41 #define AT91_ADC_TSAMOD_ADC_ONLY_MODE (0 << 0) /* ADC Mode */
42 #define AT91_ADC_TSAMOD_TS_ONLY_MODE (1 << 0) /* Touch Screen Only Mode */
43 #define AT91_ADC_TRGEN (1 << 0) /* Trigger Enable */
44 #define AT91_ADC_TRGSEL (7 << 1) /* Trigger Selection */
45 #define AT91_ADC_TRGSEL_TC0 (0 << 1)
46 #define AT91_ADC_TRGSEL_TC1 (1 << 1)
47 #define AT91_ADC_TRGSEL_TC2 (2 << 1)
48 #define AT91_ADC_TRGSEL_EXTERNAL (6 << 1)
49 #define AT91_ADC_LOWRES (1 << 4) /* Low Resolution */
50 #define AT91_ADC_SLEEP (1 << 5) /* Sleep Mode */
51 #define AT91_ADC_PENDET (1 << 6) /* Pen contact detection enable */
52 #define AT91_ADC_PRESCAL_9260 (0x3f << 8) /* Prescalar Rate Selection */
53 #define AT91_ADC_PRESCAL_9G45 (0xff << 8)
54 #define AT91_ADC_PRESCAL_(x) ((x) << 8)
55 #define AT91_ADC_STARTUP_9260 (0x1f << 16) /* Startup Up Time */
56 #define AT91_ADC_STARTUP_9G45 (0x7f << 16)
57 #define AT91_ADC_STARTUP_9X5 (0xf << 16)
58 #define AT91_ADC_STARTUP_(x) ((x) << 16)
59 #define AT91_ADC_SHTIM (0xf << 24) /* Sample & Hold Time */
60 #define AT91_ADC_SHTIM_(x) ((x) << 24)
61 #define AT91_ADC_PENDBC (0x0f << 28) /* Pen Debounce time */
62 #define AT91_ADC_PENDBC_(x) ((x) << 28)
63
64 #define AT91_ADC_TSR 0x0C
65 #define AT91_ADC_TSR_SHTIM (0xf << 24) /* Sample & Hold Time */
66 #define AT91_ADC_TSR_SHTIM_(x) ((x) << 24)
67
68 #define AT91_ADC_CHER 0x10 /* Channel Enable Register */
69 #define AT91_ADC_CHDR 0x14 /* Channel Disable Register */
70 #define AT91_ADC_CHSR 0x18 /* Channel Status Register */
71 #define AT91_ADC_CH(n) (1 << (n)) /* Channel Number */
72
73 #define AT91_ADC_SR 0x1C /* Status Register */
74 #define AT91_ADC_EOC(n) (1 << (n)) /* End of Conversion on Channel N */
75 #define AT91_ADC_OVRE(n) (1 << ((n) + 8))/* Overrun Error on Channel N */
76 #define AT91_ADC_DRDY (1 << 16) /* Data Ready */
77 #define AT91_ADC_GOVRE (1 << 17) /* General Overrun Error */
78 #define AT91_ADC_ENDRX (1 << 18) /* End of RX Buffer */
79 #define AT91_ADC_RXFUFF (1 << 19) /* RX Buffer Full */
80
81 #define AT91_ADC_SR_9X5 0x30 /* Status Register for 9x5 */
82 #define AT91_ADC_SR_DRDY_9X5 (1 << 24) /* Data Ready */
83
84 #define AT91_ADC_LCDR 0x20 /* Last Converted Data Register */
85 #define AT91_ADC_LDATA (0x3ff)
86
87 #define AT91_ADC_IER 0x24 /* Interrupt Enable Register */
88 #define AT91_ADC_IDR 0x28 /* Interrupt Disable Register */
89 #define AT91_ADC_IMR 0x2C /* Interrupt Mask Register */
90 #define AT91RL_ADC_IER_PEN (1 << 20)
91 #define AT91RL_ADC_IER_NOPEN (1 << 21)
92 #define AT91_ADC_IER_PEN (1 << 29)
93 #define AT91_ADC_IER_NOPEN (1 << 30)
94 #define AT91_ADC_IER_XRDY (1 << 20)
95 #define AT91_ADC_IER_YRDY (1 << 21)
96 #define AT91_ADC_IER_PRDY (1 << 22)
97 #define AT91_ADC_ISR_PENS (1 << 31)
98
99 #define AT91_ADC_CHR(n) (0x30 + ((n) * 4)) /* Channel Data Register N */
100 #define AT91_ADC_DATA (0x3ff)
101
102 #define AT91_ADC_CDR0_9X5 (0x50) /* Channel Data Register 0 for 9X5 */
103
104 #define AT91_ADC_ACR 0x94 /* Analog Control Register */
105 #define AT91_ADC_ACR_PENDETSENS (0x3 << 0) /* pull-up resistor */
106
107 #define AT91_ADC_TSMR 0xB0
108 #define AT91_ADC_TSMR_TSMODE (3 << 0) /* Touch Screen Mode */
109 #define AT91_ADC_TSMR_TSMODE_NONE (0 << 0)
110 #define AT91_ADC_TSMR_TSMODE_4WIRE_NO_PRESS (1 << 0)
111 #define AT91_ADC_TSMR_TSMODE_4WIRE_PRESS (2 << 0)
112 #define AT91_ADC_TSMR_TSMODE_5WIRE (3 << 0)
113 #define AT91_ADC_TSMR_TSAV (3 << 4) /* Averages samples */
114 #define AT91_ADC_TSMR_TSAV_(x) ((x) << 4)
115 #define AT91_ADC_TSMR_SCTIM (0x0f << 16) /* Switch closure time */
116 #define AT91_ADC_TSMR_SCTIM_(x) ((x) << 16)
117 #define AT91_ADC_TSMR_PENDBC (0x0f << 28) /* Pen Debounce time */
118 #define AT91_ADC_TSMR_PENDBC_(x) ((x) << 28)
119 #define AT91_ADC_TSMR_NOTSDMA (1 << 22) /* No Touchscreen DMA */
120 #define AT91_ADC_TSMR_PENDET_DIS (0 << 24) /* Pen contact detection disable */
121 #define AT91_ADC_TSMR_PENDET_ENA (1 << 24) /* Pen contact detection enable */
122
123 #define AT91_ADC_TSXPOSR 0xB4
124 #define AT91_ADC_TSYPOSR 0xB8
125 #define AT91_ADC_TSPRESSR 0xBC
126
127 #define AT91_ADC_TRGR_9260 AT91_ADC_MR
128 #define AT91_ADC_TRGR_9G45 0x08
129 #define AT91_ADC_TRGR_9X5 0xC0
130
131 /* Trigger Register bit field */
132 #define AT91_ADC_TRGR_TRGPER (0xffff << 16)
133 #define AT91_ADC_TRGR_TRGPER_(x) ((x) << 16)
134 #define AT91_ADC_TRGR_TRGMOD (0x7 << 0)
135 #define AT91_ADC_TRGR_NONE (0 << 0)
136 #define AT91_ADC_TRGR_MOD_PERIOD_TRIG (5 << 0)
137
138 #define AT91_ADC_CHAN(st, ch) \
139 (st->registers->channel_base + (ch * 4))
140 #define at91_adc_readl(st, reg) \
141 (readl_relaxed(st->reg_base + reg))
142 #define at91_adc_writel(st, reg, val) \
143 (writel_relaxed(val, st->reg_base + reg))
144
145 #define DRIVER_NAME "at91_adc"
146 #define MAX_POS_BITS 12
147
148 #define TOUCH_SAMPLE_PERIOD_US 2000 /* 2ms */
149 #define TOUCH_PEN_DETECT_DEBOUNCE_US 200
150
151 #define MAX_RLPOS_BITS 10
152 #define TOUCH_SAMPLE_PERIOD_US_RL 10000 /* 10ms, the SoC can't keep up with 2ms */
153 #define TOUCH_SHTIM 0xa
154 #define TOUCH_SCTIM_US 10 /* 10us for the Touchscreen Switches Closure Time */
155
156 /**
157 * struct at91_adc_reg_desc - Various informations relative to registers
158 * @channel_base: Base offset for the channel data registers
159 * @drdy_mask: Mask of the DRDY field in the relevant registers
160 (Interruptions registers mostly)
161 * @status_register: Offset of the Interrupt Status Register
162 * @trigger_register: Offset of the Trigger setup register
163 * @mr_prescal_mask: Mask of the PRESCAL field in the adc MR register
164 * @mr_startup_mask: Mask of the STARTUP field in the adc MR register
165 */
166 struct at91_adc_reg_desc {
167 u8 channel_base;
168 u32 drdy_mask;
169 u8 status_register;
170 u8 trigger_register;
171 u32 mr_prescal_mask;
172 u32 mr_startup_mask;
173 };
174
175 struct at91_adc_caps {
176 bool has_ts; /* Support touch screen */
177 bool has_tsmr; /* only at91sam9x5, sama5d3 have TSMR reg */
178 /*
179 * Numbers of sampling data will be averaged. Can be 0~3.
180 * Hardware can average (2 ^ ts_filter_average) sample data.
181 */
182 u8 ts_filter_average;
183 /* Pen Detection input pull-up resistor, can be 0~3 */
184 u8 ts_pen_detect_sensitivity;
185
186 /* startup time calculate function */
187 u32 (*calc_startup_ticks)(u32 startup_time, u32 adc_clk_khz);
188
189 u8 num_channels;
190 struct at91_adc_reg_desc registers;
191 };
192
193 struct at91_adc_state {
194 struct clk *adc_clk;
195 u16 *buffer;
196 unsigned long channels_mask;
197 struct clk *clk;
198 bool done;
199 int irq;
200 u16 last_value;
201 int chnb;
202 struct mutex lock;
203 u8 num_channels;
204 void __iomem *reg_base;
205 struct at91_adc_reg_desc *registers;
206 u32 startup_time;
207 u8 sample_hold_time;
208 bool sleep_mode;
209 struct iio_trigger **trig;
210 struct at91_adc_trigger *trigger_list;
211 u32 trigger_number;
212 bool use_external;
213 u32 vref_mv;
214 u32 res; /* resolution used for convertions */
215 bool low_res; /* the resolution corresponds to the lowest one */
216 wait_queue_head_t wq_data_avail;
217 struct at91_adc_caps *caps;
218
219 /*
220 * Following ADC channels are shared by touchscreen:
221 *
222 * CH0 -- Touch screen XP/UL
223 * CH1 -- Touch screen XM/UR
224 * CH2 -- Touch screen YP/LL
225 * CH3 -- Touch screen YM/Sense
226 * CH4 -- Touch screen LR(5-wire only)
227 *
228 * The bitfields below represents the reserved channel in the
229 * touchscreen mode.
230 */
231 #define CHAN_MASK_TOUCHSCREEN_4WIRE (0xf << 0)
232 #define CHAN_MASK_TOUCHSCREEN_5WIRE (0x1f << 0)
233 enum atmel_adc_ts_type touchscreen_type;
234 struct input_dev *ts_input;
235
236 u16 ts_sample_period_val;
237 u32 ts_pressure_threshold;
238 u16 ts_pendbc;
239
240 bool ts_bufferedmeasure;
241 u32 ts_prev_absx;
242 u32 ts_prev_absy;
243 };
244
245 static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
246 {
247 struct iio_poll_func *pf = p;
248 struct iio_dev *idev = pf->indio_dev;
249 struct at91_adc_state *st = iio_priv(idev);
250 struct iio_chan_spec const *chan;
251 int i, j = 0;
252
253 for (i = 0; i < idev->masklength; i++) {
254 if (!test_bit(i, idev->active_scan_mask))
255 continue;
256 chan = idev->channels + i;
257 st->buffer[j] = at91_adc_readl(st, AT91_ADC_CHAN(st, chan->channel));
258 j++;
259 }
260
261 iio_push_to_buffers_with_timestamp(idev, st->buffer, pf->timestamp);
262
263 iio_trigger_notify_done(idev->trig);
264
265 /* Needed to ACK the DRDY interruption */
266 at91_adc_readl(st, AT91_ADC_LCDR);
267
268 enable_irq(st->irq);
269
270 return IRQ_HANDLED;
271 }
272
273 /* Handler for classic adc channel eoc trigger */
274 static void handle_adc_eoc_trigger(int irq, struct iio_dev *idev)
275 {
276 struct at91_adc_state *st = iio_priv(idev);
277
278 if (iio_buffer_enabled(idev)) {
279 disable_irq_nosync(irq);
280 iio_trigger_poll(idev->trig);
281 } else {
282 st->last_value = at91_adc_readl(st, AT91_ADC_CHAN(st, st->chnb));
283 /* Needed to ACK the DRDY interruption */
284 at91_adc_readl(st, AT91_ADC_LCDR);
285 st->done = true;
286 wake_up_interruptible(&st->wq_data_avail);
287 }
288 }
289
290 static int at91_ts_sample(struct at91_adc_state *st)
291 {
292 unsigned int xscale, yscale, reg, z1, z2;
293 unsigned int x, y, pres, xpos, ypos;
294 unsigned int rxp = 1;
295 unsigned int factor = 1000;
296 struct iio_dev *idev = iio_priv_to_dev(st);
297
298 unsigned int xyz_mask_bits = st->res;
299 unsigned int xyz_mask = (1 << xyz_mask_bits) - 1;
300
301 /* calculate position */
302 /* x position = (x / xscale) * max, max = 2^MAX_POS_BITS - 1 */
303 reg = at91_adc_readl(st, AT91_ADC_TSXPOSR);
304 xpos = reg & xyz_mask;
305 x = (xpos << MAX_POS_BITS) - xpos;
306 xscale = (reg >> 16) & xyz_mask;
307 if (xscale == 0) {
308 dev_err(&idev->dev, "Error: xscale == 0!\n");
309 return -1;
310 }
311 x /= xscale;
312
313 /* y position = (y / yscale) * max, max = 2^MAX_POS_BITS - 1 */
314 reg = at91_adc_readl(st, AT91_ADC_TSYPOSR);
315 ypos = reg & xyz_mask;
316 y = (ypos << MAX_POS_BITS) - ypos;
317 yscale = (reg >> 16) & xyz_mask;
318 if (yscale == 0) {
319 dev_err(&idev->dev, "Error: yscale == 0!\n");
320 return -1;
321 }
322 y /= yscale;
323
324 /* calculate the pressure */
325 reg = at91_adc_readl(st, AT91_ADC_TSPRESSR);
326 z1 = reg & xyz_mask;
327 z2 = (reg >> 16) & xyz_mask;
328
329 if (z1 != 0)
330 pres = rxp * (x * factor / 1024) * (z2 * factor / z1 - factor)
331 / factor;
332 else
333 pres = st->ts_pressure_threshold; /* no pen contacted */
334
335 dev_dbg(&idev->dev, "xpos = %d, xscale = %d, ypos = %d, yscale = %d, z1 = %d, z2 = %d, press = %d\n",
336 xpos, xscale, ypos, yscale, z1, z2, pres);
337
338 if (pres < st->ts_pressure_threshold) {
339 dev_dbg(&idev->dev, "x = %d, y = %d, pressure = %d\n",
340 x, y, pres / factor);
341 input_report_abs(st->ts_input, ABS_X, x);
342 input_report_abs(st->ts_input, ABS_Y, y);
343 input_report_abs(st->ts_input, ABS_PRESSURE, pres);
344 input_report_key(st->ts_input, BTN_TOUCH, 1);
345 input_sync(st->ts_input);
346 } else {
347 dev_dbg(&idev->dev, "pressure too low: not reporting\n");
348 }
349
350 return 0;
351 }
352
353 static irqreturn_t at91_adc_rl_interrupt(int irq, void *private)
354 {
355 struct iio_dev *idev = private;
356 struct at91_adc_state *st = iio_priv(idev);
357 u32 status = at91_adc_readl(st, st->registers->status_register);
358 unsigned int reg;
359
360 status &= at91_adc_readl(st, AT91_ADC_IMR);
361 if (status & GENMASK(st->num_channels - 1, 0))
362 handle_adc_eoc_trigger(irq, idev);
363
364 if (status & AT91RL_ADC_IER_PEN) {
365 /* Disabling pen debounce is required to get a NOPEN irq */
366 reg = at91_adc_readl(st, AT91_ADC_MR);
367 reg &= ~AT91_ADC_PENDBC;
368 at91_adc_writel(st, AT91_ADC_MR, reg);
369
370 at91_adc_writel(st, AT91_ADC_IDR, AT91RL_ADC_IER_PEN);
371 at91_adc_writel(st, AT91_ADC_IER, AT91RL_ADC_IER_NOPEN
372 | AT91_ADC_EOC(3));
373 /* Set up period trigger for sampling */
374 at91_adc_writel(st, st->registers->trigger_register,
375 AT91_ADC_TRGR_MOD_PERIOD_TRIG |
376 AT91_ADC_TRGR_TRGPER_(st->ts_sample_period_val));
377 } else if (status & AT91RL_ADC_IER_NOPEN) {
378 reg = at91_adc_readl(st, AT91_ADC_MR);
379 reg |= AT91_ADC_PENDBC_(st->ts_pendbc) & AT91_ADC_PENDBC;
380 at91_adc_writel(st, AT91_ADC_MR, reg);
381 at91_adc_writel(st, st->registers->trigger_register,
382 AT91_ADC_TRGR_NONE);
383
384 at91_adc_writel(st, AT91_ADC_IDR, AT91RL_ADC_IER_NOPEN
385 | AT91_ADC_EOC(3));
386 at91_adc_writel(st, AT91_ADC_IER, AT91RL_ADC_IER_PEN);
387 st->ts_bufferedmeasure = false;
388 input_report_key(st->ts_input, BTN_TOUCH, 0);
389 input_sync(st->ts_input);
390 } else if (status & AT91_ADC_EOC(3) && st->ts_input) {
391 /* Conversion finished and we've a touchscreen */
392 if (st->ts_bufferedmeasure) {
393 /*
394 * Last measurement is always discarded, since it can
395 * be erroneous.
396 * Always report previous measurement
397 */
398 input_report_abs(st->ts_input, ABS_X, st->ts_prev_absx);
399 input_report_abs(st->ts_input, ABS_Y, st->ts_prev_absy);
400 input_report_key(st->ts_input, BTN_TOUCH, 1);
401 input_sync(st->ts_input);
402 } else
403 st->ts_bufferedmeasure = true;
404
405 /* Now make new measurement */
406 st->ts_prev_absx = at91_adc_readl(st, AT91_ADC_CHAN(st, 3))
407 << MAX_RLPOS_BITS;
408 st->ts_prev_absx /= at91_adc_readl(st, AT91_ADC_CHAN(st, 2));
409
410 st->ts_prev_absy = at91_adc_readl(st, AT91_ADC_CHAN(st, 1))
411 << MAX_RLPOS_BITS;
412 st->ts_prev_absy /= at91_adc_readl(st, AT91_ADC_CHAN(st, 0));
413 }
414
415 return IRQ_HANDLED;
416 }
417
418 static irqreturn_t at91_adc_9x5_interrupt(int irq, void *private)
419 {
420 struct iio_dev *idev = private;
421 struct at91_adc_state *st = iio_priv(idev);
422 u32 status = at91_adc_readl(st, st->registers->status_register);
423 const uint32_t ts_data_irq_mask =
424 AT91_ADC_IER_XRDY |
425 AT91_ADC_IER_YRDY |
426 AT91_ADC_IER_PRDY;
427
428 if (status & GENMASK(st->num_channels - 1, 0))
429 handle_adc_eoc_trigger(irq, idev);
430
431 if (status & AT91_ADC_IER_PEN) {
432 at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_PEN);
433 at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_NOPEN |
434 ts_data_irq_mask);
435 /* Set up period trigger for sampling */
436 at91_adc_writel(st, st->registers->trigger_register,
437 AT91_ADC_TRGR_MOD_PERIOD_TRIG |
438 AT91_ADC_TRGR_TRGPER_(st->ts_sample_period_val));
439 } else if (status & AT91_ADC_IER_NOPEN) {
440 at91_adc_writel(st, st->registers->trigger_register, 0);
441 at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_NOPEN |
442 ts_data_irq_mask);
443 at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_PEN);
444
445 input_report_key(st->ts_input, BTN_TOUCH, 0);
446 input_sync(st->ts_input);
447 } else if ((status & ts_data_irq_mask) == ts_data_irq_mask) {
448 /* Now all touchscreen data is ready */
449
450 if (status & AT91_ADC_ISR_PENS) {
451 /* validate data by pen contact */
452 at91_ts_sample(st);
453 } else {
454 /* triggered by event that is no pen contact, just read
455 * them to clean the interrupt and discard all.
456 */
457 at91_adc_readl(st, AT91_ADC_TSXPOSR);
458 at91_adc_readl(st, AT91_ADC_TSYPOSR);
459 at91_adc_readl(st, AT91_ADC_TSPRESSR);
460 }
461 }
462
463 return IRQ_HANDLED;
464 }
465
466 static int at91_adc_channel_init(struct iio_dev *idev)
467 {
468 struct at91_adc_state *st = iio_priv(idev);
469 struct iio_chan_spec *chan_array, *timestamp;
470 int bit, idx = 0;
471 unsigned long rsvd_mask = 0;
472
473 /* If touchscreen is enable, then reserve the adc channels */
474 if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_4WIRE)
475 rsvd_mask = CHAN_MASK_TOUCHSCREEN_4WIRE;
476 else if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_5WIRE)
477 rsvd_mask = CHAN_MASK_TOUCHSCREEN_5WIRE;
478
479 /* set up the channel mask to reserve touchscreen channels */
480 st->channels_mask &= ~rsvd_mask;
481
482 idev->num_channels = bitmap_weight(&st->channels_mask,
483 st->num_channels) + 1;
484
485 chan_array = devm_kzalloc(&idev->dev,
486 ((idev->num_channels + 1) *
487 sizeof(struct iio_chan_spec)),
488 GFP_KERNEL);
489
490 if (!chan_array)
491 return -ENOMEM;
492
493 for_each_set_bit(bit, &st->channels_mask, st->num_channels) {
494 struct iio_chan_spec *chan = chan_array + idx;
495
496 chan->type = IIO_VOLTAGE;
497 chan->indexed = 1;
498 chan->channel = bit;
499 chan->scan_index = idx;
500 chan->scan_type.sign = 'u';
501 chan->scan_type.realbits = st->res;
502 chan->scan_type.storagebits = 16;
503 chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE);
504 chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);
505 idx++;
506 }
507 timestamp = chan_array + idx;
508
509 timestamp->type = IIO_TIMESTAMP;
510 timestamp->channel = -1;
511 timestamp->scan_index = idx;
512 timestamp->scan_type.sign = 's';
513 timestamp->scan_type.realbits = 64;
514 timestamp->scan_type.storagebits = 64;
515
516 idev->channels = chan_array;
517 return idev->num_channels;
518 }
519
520 static int at91_adc_get_trigger_value_by_name(struct iio_dev *idev,
521 struct at91_adc_trigger *triggers,
522 const char *trigger_name)
523 {
524 struct at91_adc_state *st = iio_priv(idev);
525 int i;
526
527 for (i = 0; i < st->trigger_number; i++) {
528 char *name = kasprintf(GFP_KERNEL,
529 "%s-dev%d-%s",
530 idev->name,
531 idev->id,
532 triggers[i].name);
533 if (!name)
534 return -ENOMEM;
535
536 if (strcmp(trigger_name, name) == 0) {
537 kfree(name);
538 if (triggers[i].value == 0)
539 return -EINVAL;
540 return triggers[i].value;
541 }
542
543 kfree(name);
544 }
545
546 return -EINVAL;
547 }
548
549 static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
550 {
551 struct iio_dev *idev = iio_trigger_get_drvdata(trig);
552 struct at91_adc_state *st = iio_priv(idev);
553 struct at91_adc_reg_desc *reg = st->registers;
554 u32 status = at91_adc_readl(st, reg->trigger_register);
555 int value;
556 u8 bit;
557
558 value = at91_adc_get_trigger_value_by_name(idev,
559 st->trigger_list,
560 idev->trig->name);
561 if (value < 0)
562 return value;
563
564 if (state) {
565 st->buffer = kmalloc(idev->scan_bytes, GFP_KERNEL);
566 if (st->buffer == NULL)
567 return -ENOMEM;
568
569 at91_adc_writel(st, reg->trigger_register,
570 status | value);
571
572 for_each_set_bit(bit, idev->active_scan_mask,
573 st->num_channels) {
574 struct iio_chan_spec const *chan = idev->channels + bit;
575 at91_adc_writel(st, AT91_ADC_CHER,
576 AT91_ADC_CH(chan->channel));
577 }
578
579 at91_adc_writel(st, AT91_ADC_IER, reg->drdy_mask);
580
581 } else {
582 at91_adc_writel(st, AT91_ADC_IDR, reg->drdy_mask);
583
584 at91_adc_writel(st, reg->trigger_register,
585 status & ~value);
586
587 for_each_set_bit(bit, idev->active_scan_mask,
588 st->num_channels) {
589 struct iio_chan_spec const *chan = idev->channels + bit;
590 at91_adc_writel(st, AT91_ADC_CHDR,
591 AT91_ADC_CH(chan->channel));
592 }
593 kfree(st->buffer);
594 }
595
596 return 0;
597 }
598
599 static const struct iio_trigger_ops at91_adc_trigger_ops = {
600 .set_trigger_state = &at91_adc_configure_trigger,
601 };
602
603 static struct iio_trigger *at91_adc_allocate_trigger(struct iio_dev *idev,
604 struct at91_adc_trigger *trigger)
605 {
606 struct iio_trigger *trig;
607 int ret;
608
609 trig = iio_trigger_alloc("%s-dev%d-%s", idev->name,
610 idev->id, trigger->name);
611 if (trig == NULL)
612 return NULL;
613
614 trig->dev.parent = idev->dev.parent;
615 iio_trigger_set_drvdata(trig, idev);
616 trig->ops = &at91_adc_trigger_ops;
617
618 ret = iio_trigger_register(trig);
619 if (ret)
620 return NULL;
621
622 return trig;
623 }
624
625 static int at91_adc_trigger_init(struct iio_dev *idev)
626 {
627 struct at91_adc_state *st = iio_priv(idev);
628 int i, ret;
629
630 st->trig = devm_kcalloc(&idev->dev,
631 st->trigger_number, sizeof(*st->trig),
632 GFP_KERNEL);
633
634 if (st->trig == NULL) {
635 ret = -ENOMEM;
636 goto error_ret;
637 }
638
639 for (i = 0; i < st->trigger_number; i++) {
640 if (st->trigger_list[i].is_external && !(st->use_external))
641 continue;
642
643 st->trig[i] = at91_adc_allocate_trigger(idev,
644 st->trigger_list + i);
645 if (st->trig[i] == NULL) {
646 dev_err(&idev->dev,
647 "Could not allocate trigger %d\n", i);
648 ret = -ENOMEM;
649 goto error_trigger;
650 }
651 }
652
653 return 0;
654
655 error_trigger:
656 for (i--; i >= 0; i--) {
657 iio_trigger_unregister(st->trig[i]);
658 iio_trigger_free(st->trig[i]);
659 }
660 error_ret:
661 return ret;
662 }
663
664 static void at91_adc_trigger_remove(struct iio_dev *idev)
665 {
666 struct at91_adc_state *st = iio_priv(idev);
667 int i;
668
669 for (i = 0; i < st->trigger_number; i++) {
670 iio_trigger_unregister(st->trig[i]);
671 iio_trigger_free(st->trig[i]);
672 }
673 }
674
675 static int at91_adc_buffer_init(struct iio_dev *idev)
676 {
677 return iio_triggered_buffer_setup(idev, &iio_pollfunc_store_time,
678 &at91_adc_trigger_handler, NULL);
679 }
680
681 static void at91_adc_buffer_remove(struct iio_dev *idev)
682 {
683 iio_triggered_buffer_cleanup(idev);
684 }
685
686 static int at91_adc_read_raw(struct iio_dev *idev,
687 struct iio_chan_spec const *chan,
688 int *val, int *val2, long mask)
689 {
690 struct at91_adc_state *st = iio_priv(idev);
691 int ret;
692
693 switch (mask) {
694 case IIO_CHAN_INFO_RAW:
695 mutex_lock(&st->lock);
696
697 st->chnb = chan->channel;
698 at91_adc_writel(st, AT91_ADC_CHER,
699 AT91_ADC_CH(chan->channel));
700 at91_adc_writel(st, AT91_ADC_IER, BIT(chan->channel));
701 at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_START);
702
703 ret = wait_event_interruptible_timeout(st->wq_data_avail,
704 st->done,
705 msecs_to_jiffies(1000));
706
707 /* Disable interrupts, regardless if adc conversion was
708 * successful or not
709 */
710 at91_adc_writel(st, AT91_ADC_CHDR,
711 AT91_ADC_CH(chan->channel));
712 at91_adc_writel(st, AT91_ADC_IDR, BIT(chan->channel));
713
714 if (ret > 0) {
715 /* a valid conversion took place */
716 *val = st->last_value;
717 st->last_value = 0;
718 st->done = false;
719 ret = IIO_VAL_INT;
720 } else if (ret == 0) {
721 /* conversion timeout */
722 dev_err(&idev->dev, "ADC Channel %d timeout.\n",
723 chan->channel);
724 ret = -ETIMEDOUT;
725 }
726
727 mutex_unlock(&st->lock);
728 return ret;
729
730 case IIO_CHAN_INFO_SCALE:
731 *val = st->vref_mv;
732 *val2 = chan->scan_type.realbits;
733 return IIO_VAL_FRACTIONAL_LOG2;
734 default:
735 break;
736 }
737 return -EINVAL;
738 }
739
740 static int at91_adc_of_get_resolution(struct at91_adc_state *st,
741 struct platform_device *pdev)
742 {
743 struct iio_dev *idev = iio_priv_to_dev(st);
744 struct device_node *np = pdev->dev.of_node;
745 int count, i, ret = 0;
746 char *res_name, *s;
747 u32 *resolutions;
748
749 count = of_property_count_strings(np, "atmel,adc-res-names");
750 if (count < 2) {
751 dev_err(&idev->dev, "You must specified at least two resolution names for "
752 "adc-res-names property in the DT\n");
753 return count;
754 }
755
756 resolutions = kmalloc_array(count, sizeof(*resolutions), GFP_KERNEL);
757 if (!resolutions)
758 return -ENOMEM;
759
760 if (of_property_read_u32_array(np, "atmel,adc-res", resolutions, count)) {
761 dev_err(&idev->dev, "Missing adc-res property in the DT.\n");
762 ret = -ENODEV;
763 goto ret;
764 }
765
766 if (of_property_read_string(np, "atmel,adc-use-res", (const char **)&res_name))
767 res_name = "highres";
768
769 for (i = 0; i < count; i++) {
770 if (of_property_read_string_index(np, "atmel,adc-res-names", i, (const char **)&s))
771 continue;
772
773 if (strcmp(res_name, s))
774 continue;
775
776 st->res = resolutions[i];
777 if (!strcmp(res_name, "lowres"))
778 st->low_res = true;
779 else
780 st->low_res = false;
781
782 dev_info(&idev->dev, "Resolution used: %u bits\n", st->res);
783 goto ret;
784 }
785
786 dev_err(&idev->dev, "There is no resolution for %s\n", res_name);
787
788 ret:
789 kfree(resolutions);
790 return ret;
791 }
792
793 static u32 calc_startup_ticks_9260(u32 startup_time, u32 adc_clk_khz)
794 {
795 /*
796 * Number of ticks needed to cover the startup time of the ADC
797 * as defined in the electrical characteristics of the board,
798 * divided by 8. The formula thus is :
799 * Startup Time = (ticks + 1) * 8 / ADC Clock
800 */
801 return round_up((startup_time * adc_clk_khz / 1000) - 1, 8) / 8;
802 }
803
804 static u32 calc_startup_ticks_9x5(u32 startup_time, u32 adc_clk_khz)
805 {
806 /*
807 * For sama5d3x and at91sam9x5, the formula changes to:
808 * Startup Time = <lookup_table_value> / ADC Clock
809 */
810 static const int startup_lookup[] = {
811 0, 8, 16, 24,
812 64, 80, 96, 112,
813 512, 576, 640, 704,
814 768, 832, 896, 960
815 };
816 int i, size = ARRAY_SIZE(startup_lookup);
817 unsigned int ticks;
818
819 ticks = startup_time * adc_clk_khz / 1000;
820 for (i = 0; i < size; i++)
821 if (ticks < startup_lookup[i])
822 break;
823
824 ticks = i;
825 if (ticks == size)
826 /* Reach the end of lookup table */
827 ticks = size - 1;
828
829 return ticks;
830 }
831
832 static const struct of_device_id at91_adc_dt_ids[];
833
834 static int at91_adc_probe_dt_ts(struct device_node *node,
835 struct at91_adc_state *st, struct device *dev)
836 {
837 int ret;
838 u32 prop;
839
840 ret = of_property_read_u32(node, "atmel,adc-ts-wires", &prop);
841 if (ret) {
842 dev_info(dev, "ADC Touch screen is disabled.\n");
843 return 0;
844 }
845
846 switch (prop) {
847 case 4:
848 case 5:
849 st->touchscreen_type = prop;
850 break;
851 default:
852 dev_err(dev, "Unsupported number of touchscreen wires (%d). Should be 4 or 5.\n", prop);
853 return -EINVAL;
854 }
855
856 if (!st->caps->has_tsmr)
857 return 0;
858 prop = 0;
859 of_property_read_u32(node, "atmel,adc-ts-pressure-threshold", &prop);
860 st->ts_pressure_threshold = prop;
861 if (st->ts_pressure_threshold) {
862 return 0;
863 } else {
864 dev_err(dev, "Invalid pressure threshold for the touchscreen\n");
865 return -EINVAL;
866 }
867 }
868
869 static int at91_adc_probe_dt(struct at91_adc_state *st,
870 struct platform_device *pdev)
871 {
872 struct iio_dev *idev = iio_priv_to_dev(st);
873 struct device_node *node = pdev->dev.of_node;
874 struct device_node *trig_node;
875 int i = 0, ret;
876 u32 prop;
877
878 if (!node)
879 return -EINVAL;
880
881 st->caps = (struct at91_adc_caps *)
882 of_match_device(at91_adc_dt_ids, &pdev->dev)->data;
883
884 st->use_external = of_property_read_bool(node, "atmel,adc-use-external-triggers");
885
886 if (of_property_read_u32(node, "atmel,adc-channels-used", &prop)) {
887 dev_err(&idev->dev, "Missing adc-channels-used property in the DT.\n");
888 ret = -EINVAL;
889 goto error_ret;
890 }
891 st->channels_mask = prop;
892
893 st->sleep_mode = of_property_read_bool(node, "atmel,adc-sleep-mode");
894
895 if (of_property_read_u32(node, "atmel,adc-startup-time", &prop)) {
896 dev_err(&idev->dev, "Missing adc-startup-time property in the DT.\n");
897 ret = -EINVAL;
898 goto error_ret;
899 }
900 st->startup_time = prop;
901
902 prop = 0;
903 of_property_read_u32(node, "atmel,adc-sample-hold-time", &prop);
904 st->sample_hold_time = prop;
905
906 if (of_property_read_u32(node, "atmel,adc-vref", &prop)) {
907 dev_err(&idev->dev, "Missing adc-vref property in the DT.\n");
908 ret = -EINVAL;
909 goto error_ret;
910 }
911 st->vref_mv = prop;
912
913 ret = at91_adc_of_get_resolution(st, pdev);
914 if (ret)
915 goto error_ret;
916
917 st->registers = &st->caps->registers;
918 st->num_channels = st->caps->num_channels;
919 st->trigger_number = of_get_child_count(node);
920 st->trigger_list = devm_kcalloc(&idev->dev,
921 st->trigger_number,
922 sizeof(struct at91_adc_trigger),
923 GFP_KERNEL);
924 if (!st->trigger_list) {
925 dev_err(&idev->dev, "Could not allocate trigger list memory.\n");
926 ret = -ENOMEM;
927 goto error_ret;
928 }
929
930 for_each_child_of_node(node, trig_node) {
931 struct at91_adc_trigger *trig = st->trigger_list + i;
932 const char *name;
933
934 if (of_property_read_string(trig_node, "trigger-name", &name)) {
935 dev_err(&idev->dev, "Missing trigger-name property in the DT.\n");
936 ret = -EINVAL;
937 goto error_ret;
938 }
939 trig->name = name;
940
941 if (of_property_read_u32(trig_node, "trigger-value", &prop)) {
942 dev_err(&idev->dev, "Missing trigger-value property in the DT.\n");
943 ret = -EINVAL;
944 goto error_ret;
945 }
946 trig->value = prop;
947 trig->is_external = of_property_read_bool(trig_node, "trigger-external");
948 i++;
949 }
950
951 /* Check if touchscreen is supported. */
952 if (st->caps->has_ts)
953 return at91_adc_probe_dt_ts(node, st, &idev->dev);
954 else
955 dev_info(&idev->dev, "not support touchscreen in the adc compatible string.\n");
956
957 return 0;
958
959 error_ret:
960 return ret;
961 }
962
963 static int at91_adc_probe_pdata(struct at91_adc_state *st,
964 struct platform_device *pdev)
965 {
966 struct at91_adc_data *pdata = pdev->dev.platform_data;
967
968 if (!pdata)
969 return -EINVAL;
970
971 st->caps = (struct at91_adc_caps *)
972 platform_get_device_id(pdev)->driver_data;
973
974 st->use_external = pdata->use_external_triggers;
975 st->vref_mv = pdata->vref;
976 st->channels_mask = pdata->channels_used;
977 st->num_channels = st->caps->num_channels;
978 st->startup_time = pdata->startup_time;
979 st->trigger_number = pdata->trigger_number;
980 st->trigger_list = pdata->trigger_list;
981 st->registers = &st->caps->registers;
982 st->touchscreen_type = pdata->touchscreen_type;
983
984 return 0;
985 }
986
987 static const struct iio_info at91_adc_info = {
988 .read_raw = &at91_adc_read_raw,
989 };
990
991 /* Touchscreen related functions */
992 static int atmel_ts_open(struct input_dev *dev)
993 {
994 struct at91_adc_state *st = input_get_drvdata(dev);
995
996 if (st->caps->has_tsmr)
997 at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_PEN);
998 else
999 at91_adc_writel(st, AT91_ADC_IER, AT91RL_ADC_IER_PEN);
1000 return 0;
1001 }
1002
1003 static void atmel_ts_close(struct input_dev *dev)
1004 {
1005 struct at91_adc_state *st = input_get_drvdata(dev);
1006
1007 if (st->caps->has_tsmr)
1008 at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_PEN);
1009 else
1010 at91_adc_writel(st, AT91_ADC_IDR, AT91RL_ADC_IER_PEN);
1011 }
1012
1013 static int at91_ts_hw_init(struct at91_adc_state *st, u32 adc_clk_khz)
1014 {
1015 struct iio_dev *idev = iio_priv_to_dev(st);
1016 u32 reg = 0;
1017 u32 tssctim = 0;
1018 int i = 0;
1019
1020 /* a Pen Detect Debounce Time is necessary for the ADC Touch to avoid
1021 * pen detect noise.
1022 * The formula is : Pen Detect Debounce Time = (2 ^ pendbc) / ADCClock
1023 */
1024 st->ts_pendbc = round_up(TOUCH_PEN_DETECT_DEBOUNCE_US * adc_clk_khz /
1025 1000, 1);
1026
1027 while (st->ts_pendbc >> ++i)
1028 ; /* Empty! Find the shift offset */
1029 if (abs(st->ts_pendbc - (1 << i)) < abs(st->ts_pendbc - (1 << (i - 1))))
1030 st->ts_pendbc = i;
1031 else
1032 st->ts_pendbc = i - 1;
1033
1034 if (!st->caps->has_tsmr) {
1035 reg = at91_adc_readl(st, AT91_ADC_MR);
1036 reg |= AT91_ADC_TSAMOD_TS_ONLY_MODE | AT91_ADC_PENDET;
1037
1038 reg |= AT91_ADC_PENDBC_(st->ts_pendbc) & AT91_ADC_PENDBC;
1039 at91_adc_writel(st, AT91_ADC_MR, reg);
1040
1041 reg = AT91_ADC_TSR_SHTIM_(TOUCH_SHTIM) & AT91_ADC_TSR_SHTIM;
1042 at91_adc_writel(st, AT91_ADC_TSR, reg);
1043
1044 st->ts_sample_period_val = round_up((TOUCH_SAMPLE_PERIOD_US_RL *
1045 adc_clk_khz / 1000) - 1, 1);
1046
1047 return 0;
1048 }
1049
1050 /* Touchscreen Switches Closure time needed for allowing the value to
1051 * stabilize.
1052 * Switch Closure Time = (TSSCTIM * 4) ADCClock periods
1053 */
1054 tssctim = DIV_ROUND_UP(TOUCH_SCTIM_US * adc_clk_khz / 1000, 4);
1055 dev_dbg(&idev->dev, "adc_clk at: %d KHz, tssctim at: %d\n",
1056 adc_clk_khz, tssctim);
1057
1058 if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_4WIRE)
1059 reg = AT91_ADC_TSMR_TSMODE_4WIRE_PRESS;
1060 else
1061 reg = AT91_ADC_TSMR_TSMODE_5WIRE;
1062
1063 reg |= AT91_ADC_TSMR_SCTIM_(tssctim) & AT91_ADC_TSMR_SCTIM;
1064 reg |= AT91_ADC_TSMR_TSAV_(st->caps->ts_filter_average)
1065 & AT91_ADC_TSMR_TSAV;
1066 reg |= AT91_ADC_TSMR_PENDBC_(st->ts_pendbc) & AT91_ADC_TSMR_PENDBC;
1067 reg |= AT91_ADC_TSMR_NOTSDMA;
1068 reg |= AT91_ADC_TSMR_PENDET_ENA;
1069 reg |= 0x03 << 8; /* TSFREQ, needs to be bigger than TSAV */
1070
1071 at91_adc_writel(st, AT91_ADC_TSMR, reg);
1072
1073 /* Change adc internal resistor value for better pen detection,
1074 * default value is 100 kOhm.
1075 * 0 = 200 kOhm, 1 = 150 kOhm, 2 = 100 kOhm, 3 = 50 kOhm
1076 * option only available on ES2 and higher
1077 */
1078 at91_adc_writel(st, AT91_ADC_ACR, st->caps->ts_pen_detect_sensitivity
1079 & AT91_ADC_ACR_PENDETSENS);
1080
1081 /* Sample Period Time = (TRGPER + 1) / ADCClock */
1082 st->ts_sample_period_val = round_up((TOUCH_SAMPLE_PERIOD_US *
1083 adc_clk_khz / 1000) - 1, 1);
1084
1085 return 0;
1086 }
1087
1088 static int at91_ts_register(struct at91_adc_state *st,
1089 struct platform_device *pdev)
1090 {
1091 struct input_dev *input;
1092 struct iio_dev *idev = iio_priv_to_dev(st);
1093 int ret;
1094
1095 input = input_allocate_device();
1096 if (!input) {
1097 dev_err(&idev->dev, "Failed to allocate TS device!\n");
1098 return -ENOMEM;
1099 }
1100
1101 input->name = DRIVER_NAME;
1102 input->id.bustype = BUS_HOST;
1103 input->dev.parent = &pdev->dev;
1104 input->open = atmel_ts_open;
1105 input->close = atmel_ts_close;
1106
1107 __set_bit(EV_ABS, input->evbit);
1108 __set_bit(EV_KEY, input->evbit);
1109 __set_bit(BTN_TOUCH, input->keybit);
1110 if (st->caps->has_tsmr) {
1111 input_set_abs_params(input, ABS_X, 0, (1 << MAX_POS_BITS) - 1,
1112 0, 0);
1113 input_set_abs_params(input, ABS_Y, 0, (1 << MAX_POS_BITS) - 1,
1114 0, 0);
1115 input_set_abs_params(input, ABS_PRESSURE, 0, 0xffffff, 0, 0);
1116 } else {
1117 if (st->touchscreen_type != ATMEL_ADC_TOUCHSCREEN_4WIRE) {
1118 dev_err(&pdev->dev,
1119 "This touchscreen controller only support 4 wires\n");
1120 ret = -EINVAL;
1121 goto err;
1122 }
1123
1124 input_set_abs_params(input, ABS_X, 0, (1 << MAX_RLPOS_BITS) - 1,
1125 0, 0);
1126 input_set_abs_params(input, ABS_Y, 0, (1 << MAX_RLPOS_BITS) - 1,
1127 0, 0);
1128 }
1129
1130 st->ts_input = input;
1131 input_set_drvdata(input, st);
1132
1133 ret = input_register_device(input);
1134 if (ret)
1135 goto err;
1136
1137 return ret;
1138
1139 err:
1140 input_free_device(st->ts_input);
1141 return ret;
1142 }
1143
1144 static void at91_ts_unregister(struct at91_adc_state *st)
1145 {
1146 input_unregister_device(st->ts_input);
1147 }
1148
1149 static int at91_adc_probe(struct platform_device *pdev)
1150 {
1151 unsigned int prsc, mstrclk, ticks, adc_clk, adc_clk_khz, shtim;
1152 int ret;
1153 struct iio_dev *idev;
1154 struct at91_adc_state *st;
1155 struct resource *res;
1156 u32 reg;
1157
1158 idev = devm_iio_device_alloc(&pdev->dev, sizeof(struct at91_adc_state));
1159 if (!idev)
1160 return -ENOMEM;
1161
1162 st = iio_priv(idev);
1163
1164 if (pdev->dev.of_node)
1165 ret = at91_adc_probe_dt(st, pdev);
1166 else
1167 ret = at91_adc_probe_pdata(st, pdev);
1168
1169 if (ret) {
1170 dev_err(&pdev->dev, "No platform data available.\n");
1171 return -EINVAL;
1172 }
1173
1174 platform_set_drvdata(pdev, idev);
1175
1176 idev->dev.parent = &pdev->dev;
1177 idev->name = dev_name(&pdev->dev);
1178 idev->modes = INDIO_DIRECT_MODE;
1179 idev->info = &at91_adc_info;
1180
1181 st->irq = platform_get_irq(pdev, 0);
1182 if (st->irq < 0)
1183 return -ENODEV;
1184
1185 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1186
1187 st->reg_base = devm_ioremap_resource(&pdev->dev, res);
1188 if (IS_ERR(st->reg_base))
1189 return PTR_ERR(st->reg_base);
1190
1191
1192 /*
1193 * Disable all IRQs before setting up the handler
1194 */
1195 at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_SWRST);
1196 at91_adc_writel(st, AT91_ADC_IDR, 0xFFFFFFFF);
1197
1198 if (st->caps->has_tsmr)
1199 ret = request_irq(st->irq, at91_adc_9x5_interrupt, 0,
1200 pdev->dev.driver->name, idev);
1201 else
1202 ret = request_irq(st->irq, at91_adc_rl_interrupt, 0,
1203 pdev->dev.driver->name, idev);
1204 if (ret) {
1205 dev_err(&pdev->dev, "Failed to allocate IRQ.\n");
1206 return ret;
1207 }
1208
1209 st->clk = devm_clk_get(&pdev->dev, "adc_clk");
1210 if (IS_ERR(st->clk)) {
1211 dev_err(&pdev->dev, "Failed to get the clock.\n");
1212 ret = PTR_ERR(st->clk);
1213 goto error_free_irq;
1214 }
1215
1216 ret = clk_prepare_enable(st->clk);
1217 if (ret) {
1218 dev_err(&pdev->dev,
1219 "Could not prepare or enable the clock.\n");
1220 goto error_free_irq;
1221 }
1222
1223 st->adc_clk = devm_clk_get(&pdev->dev, "adc_op_clk");
1224 if (IS_ERR(st->adc_clk)) {
1225 dev_err(&pdev->dev, "Failed to get the ADC clock.\n");
1226 ret = PTR_ERR(st->adc_clk);
1227 goto error_disable_clk;
1228 }
1229
1230 ret = clk_prepare_enable(st->adc_clk);
1231 if (ret) {
1232 dev_err(&pdev->dev,
1233 "Could not prepare or enable the ADC clock.\n");
1234 goto error_disable_clk;
1235 }
1236
1237 /*
1238 * Prescaler rate computation using the formula from the Atmel's
1239 * datasheet : ADC Clock = MCK / ((Prescaler + 1) * 2), ADC Clock being
1240 * specified by the electrical characteristics of the board.
1241 */
1242 mstrclk = clk_get_rate(st->clk);
1243 adc_clk = clk_get_rate(st->adc_clk);
1244 adc_clk_khz = adc_clk / 1000;
1245
1246 dev_dbg(&pdev->dev, "Master clock is set as: %d Hz, adc_clk should set as: %d Hz\n",
1247 mstrclk, adc_clk);
1248
1249 prsc = (mstrclk / (2 * adc_clk)) - 1;
1250
1251 if (!st->startup_time) {
1252 dev_err(&pdev->dev, "No startup time available.\n");
1253 ret = -EINVAL;
1254 goto error_disable_adc_clk;
1255 }
1256 ticks = (*st->caps->calc_startup_ticks)(st->startup_time, adc_clk_khz);
1257
1258 /*
1259 * a minimal Sample and Hold Time is necessary for the ADC to guarantee
1260 * the best converted final value between two channels selection
1261 * The formula thus is : Sample and Hold Time = (shtim + 1) / ADCClock
1262 */
1263 if (st->sample_hold_time > 0)
1264 shtim = round_up((st->sample_hold_time * adc_clk_khz / 1000)
1265 - 1, 1);
1266 else
1267 shtim = 0;
1268
1269 reg = AT91_ADC_PRESCAL_(prsc) & st->registers->mr_prescal_mask;
1270 reg |= AT91_ADC_STARTUP_(ticks) & st->registers->mr_startup_mask;
1271 if (st->low_res)
1272 reg |= AT91_ADC_LOWRES;
1273 if (st->sleep_mode)
1274 reg |= AT91_ADC_SLEEP;
1275 reg |= AT91_ADC_SHTIM_(shtim) & AT91_ADC_SHTIM;
1276 at91_adc_writel(st, AT91_ADC_MR, reg);
1277
1278 /* Setup the ADC channels available on the board */
1279 ret = at91_adc_channel_init(idev);
1280 if (ret < 0) {
1281 dev_err(&pdev->dev, "Couldn't initialize the channels.\n");
1282 goto error_disable_adc_clk;
1283 }
1284
1285 init_waitqueue_head(&st->wq_data_avail);
1286 mutex_init(&st->lock);
1287
1288 /*
1289 * Since touch screen will set trigger register as period trigger. So
1290 * when touch screen is enabled, then we have to disable hardware
1291 * trigger for classic adc.
1292 */
1293 if (!st->touchscreen_type) {
1294 ret = at91_adc_buffer_init(idev);
1295 if (ret < 0) {
1296 dev_err(&pdev->dev, "Couldn't initialize the buffer.\n");
1297 goto error_disable_adc_clk;
1298 }
1299
1300 ret = at91_adc_trigger_init(idev);
1301 if (ret < 0) {
1302 dev_err(&pdev->dev, "Couldn't setup the triggers.\n");
1303 at91_adc_buffer_remove(idev);
1304 goto error_disable_adc_clk;
1305 }
1306 } else {
1307 ret = at91_ts_register(st, pdev);
1308 if (ret)
1309 goto error_disable_adc_clk;
1310
1311 at91_ts_hw_init(st, adc_clk_khz);
1312 }
1313
1314 ret = iio_device_register(idev);
1315 if (ret < 0) {
1316 dev_err(&pdev->dev, "Couldn't register the device.\n");
1317 goto error_iio_device_register;
1318 }
1319
1320 return 0;
1321
1322 error_iio_device_register:
1323 if (!st->touchscreen_type) {
1324 at91_adc_trigger_remove(idev);
1325 at91_adc_buffer_remove(idev);
1326 } else {
1327 at91_ts_unregister(st);
1328 }
1329 error_disable_adc_clk:
1330 clk_disable_unprepare(st->adc_clk);
1331 error_disable_clk:
1332 clk_disable_unprepare(st->clk);
1333 error_free_irq:
1334 free_irq(st->irq, idev);
1335 return ret;
1336 }
1337
1338 static int at91_adc_remove(struct platform_device *pdev)
1339 {
1340 struct iio_dev *idev = platform_get_drvdata(pdev);
1341 struct at91_adc_state *st = iio_priv(idev);
1342
1343 iio_device_unregister(idev);
1344 if (!st->touchscreen_type) {
1345 at91_adc_trigger_remove(idev);
1346 at91_adc_buffer_remove(idev);
1347 } else {
1348 at91_ts_unregister(st);
1349 }
1350 clk_disable_unprepare(st->adc_clk);
1351 clk_disable_unprepare(st->clk);
1352 free_irq(st->irq, idev);
1353
1354 return 0;
1355 }
1356
1357 #ifdef CONFIG_PM_SLEEP
1358 static int at91_adc_suspend(struct device *dev)
1359 {
1360 struct iio_dev *idev = dev_get_drvdata(dev);
1361 struct at91_adc_state *st = iio_priv(idev);
1362
1363 pinctrl_pm_select_sleep_state(dev);
1364 clk_disable_unprepare(st->clk);
1365
1366 return 0;
1367 }
1368
1369 static int at91_adc_resume(struct device *dev)
1370 {
1371 struct iio_dev *idev = dev_get_drvdata(dev);
1372 struct at91_adc_state *st = iio_priv(idev);
1373
1374 clk_prepare_enable(st->clk);
1375 pinctrl_pm_select_default_state(dev);
1376
1377 return 0;
1378 }
1379 #endif
1380
1381 static SIMPLE_DEV_PM_OPS(at91_adc_pm_ops, at91_adc_suspend, at91_adc_resume);
1382
1383 static struct at91_adc_caps at91sam9260_caps = {
1384 .calc_startup_ticks = calc_startup_ticks_9260,
1385 .num_channels = 4,
1386 .registers = {
1387 .channel_base = AT91_ADC_CHR(0),
1388 .drdy_mask = AT91_ADC_DRDY,
1389 .status_register = AT91_ADC_SR,
1390 .trigger_register = AT91_ADC_TRGR_9260,
1391 .mr_prescal_mask = AT91_ADC_PRESCAL_9260,
1392 .mr_startup_mask = AT91_ADC_STARTUP_9260,
1393 },
1394 };
1395
1396 static struct at91_adc_caps at91sam9rl_caps = {
1397 .has_ts = true,
1398 .calc_startup_ticks = calc_startup_ticks_9260, /* same as 9260 */
1399 .num_channels = 6,
1400 .registers = {
1401 .channel_base = AT91_ADC_CHR(0),
1402 .drdy_mask = AT91_ADC_DRDY,
1403 .status_register = AT91_ADC_SR,
1404 .trigger_register = AT91_ADC_TRGR_9G45,
1405 .mr_prescal_mask = AT91_ADC_PRESCAL_9260,
1406 .mr_startup_mask = AT91_ADC_STARTUP_9G45,
1407 },
1408 };
1409
1410 static struct at91_adc_caps at91sam9g45_caps = {
1411 .has_ts = true,
1412 .calc_startup_ticks = calc_startup_ticks_9260, /* same as 9260 */
1413 .num_channels = 8,
1414 .registers = {
1415 .channel_base = AT91_ADC_CHR(0),
1416 .drdy_mask = AT91_ADC_DRDY,
1417 .status_register = AT91_ADC_SR,
1418 .trigger_register = AT91_ADC_TRGR_9G45,
1419 .mr_prescal_mask = AT91_ADC_PRESCAL_9G45,
1420 .mr_startup_mask = AT91_ADC_STARTUP_9G45,
1421 },
1422 };
1423
1424 static struct at91_adc_caps at91sam9x5_caps = {
1425 .has_ts = true,
1426 .has_tsmr = true,
1427 .ts_filter_average = 3,
1428 .ts_pen_detect_sensitivity = 2,
1429 .calc_startup_ticks = calc_startup_ticks_9x5,
1430 .num_channels = 12,
1431 .registers = {
1432 .channel_base = AT91_ADC_CDR0_9X5,
1433 .drdy_mask = AT91_ADC_SR_DRDY_9X5,
1434 .status_register = AT91_ADC_SR_9X5,
1435 .trigger_register = AT91_ADC_TRGR_9X5,
1436 /* prescal mask is same as 9G45 */
1437 .mr_prescal_mask = AT91_ADC_PRESCAL_9G45,
1438 .mr_startup_mask = AT91_ADC_STARTUP_9X5,
1439 },
1440 };
1441
1442 static const struct of_device_id at91_adc_dt_ids[] = {
1443 { .compatible = "atmel,at91sam9260-adc", .data = &at91sam9260_caps },
1444 { .compatible = "atmel,at91sam9rl-adc", .data = &at91sam9rl_caps },
1445 { .compatible = "atmel,at91sam9g45-adc", .data = &at91sam9g45_caps },
1446 { .compatible = "atmel,at91sam9x5-adc", .data = &at91sam9x5_caps },
1447 {},
1448 };
1449 MODULE_DEVICE_TABLE(of, at91_adc_dt_ids);
1450
1451 static const struct platform_device_id at91_adc_ids[] = {
1452 {
1453 .name = "at91sam9260-adc",
1454 .driver_data = (unsigned long)&at91sam9260_caps,
1455 }, {
1456 .name = "at91sam9rl-adc",
1457 .driver_data = (unsigned long)&at91sam9rl_caps,
1458 }, {
1459 .name = "at91sam9g45-adc",
1460 .driver_data = (unsigned long)&at91sam9g45_caps,
1461 }, {
1462 .name = "at91sam9x5-adc",
1463 .driver_data = (unsigned long)&at91sam9x5_caps,
1464 }, {
1465 /* terminator */
1466 }
1467 };
1468 MODULE_DEVICE_TABLE(platform, at91_adc_ids);
1469
1470 static struct platform_driver at91_adc_driver = {
1471 .probe = at91_adc_probe,
1472 .remove = at91_adc_remove,
1473 .id_table = at91_adc_ids,
1474 .driver = {
1475 .name = DRIVER_NAME,
1476 .of_match_table = of_match_ptr(at91_adc_dt_ids),
1477 .pm = &at91_adc_pm_ops,
1478 },
1479 };
1480
1481 module_platform_driver(at91_adc_driver);
1482
1483 MODULE_LICENSE("GPL");
1484 MODULE_DESCRIPTION("Atmel AT91 ADC Driver");
1485 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
Linux with added FPC-III support