1 /*
2  * Support for configuration of IO Delay module found on Texas Instruments SoCs
3  * such as DRA7
4  *
5  * Copyright (C) 2015-2017 Texas Instruments Incorporated - https://www.ti.com/
6  *
7  * This file is licensed under the terms of the GNU General Public
8  * License version 2. This program is licensed "as is" without any
9  * warranty of any kind, whether express or implied.
10  */
11 
12 #include <linux/err.h>
13 #include <linux/init.h>
14 #include <linux/io.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/of_device.h>
18 #include <linux/pinctrl/pinconf.h>
19 #include <linux/pinctrl/pinconf-generic.h>
20 #include <linux/pinctrl/pinctrl.h>
21 #include <linux/regmap.h>
22 #include <linux/slab.h>
23 
24 #include "../core.h"
25 #include "../devicetree.h"
26 
27 #define DRIVER_NAME	"ti-iodelay"
28 
29 /**
30  * struct ti_iodelay_reg_data - Describes the registers for the iodelay instance
31  * @signature_mask: CONFIG_REG mask for the signature bits (see TRM)
32  * @signature_value: CONFIG_REG signature value to be written (see TRM)
33  * @lock_mask: CONFIG_REG mask for the lock bits (see TRM)
34  * @lock_val: CONFIG_REG lock value for the lock bits (see TRM)
35  * @unlock_val:CONFIG_REG unlock value for the lock bits (see TRM)
36  * @binary_data_coarse_mask: CONFIG_REG coarse mask (see TRM)
37  * @binary_data_fine_mask: CONFIG_REG fine mask (see TRM)
38  * @reg_refclk_offset: Refclk register offset
39  * @refclk_period_mask: Refclk mask
40  * @reg_coarse_offset: Coarse register configuration offset
41  * @coarse_delay_count_mask: Coarse delay count mask
42  * @coarse_ref_count_mask: Coarse ref count mask
43  * @reg_fine_offset: Fine register configuration offset
44  * @fine_delay_count_mask: Fine delay count mask
45  * @fine_ref_count_mask: Fine ref count mask
46  * @reg_global_lock_offset: Global iodelay module lock register offset
47  * @global_lock_mask: Lock mask
48  * @global_unlock_val: Unlock value
49  * @global_lock_val: Lock value
50  * @reg_start_offset: Offset to iodelay registers after the CONFIG_REG_0 to 8
51  * @reg_nr_per_pin: Number of iodelay registers for each pin
52  * @regmap_config: Regmap configuration for the IODelay region
53  */
54 struct ti_iodelay_reg_data {
55 	u32 signature_mask;
56 	u32 signature_value;
57 	u32 lock_mask;
58 	u32 lock_val;
59 	u32 unlock_val;
60 	u32 binary_data_coarse_mask;
61 	u32 binary_data_fine_mask;
62 
63 	u32 reg_refclk_offset;
64 	u32 refclk_period_mask;
65 
66 	u32 reg_coarse_offset;
67 	u32 coarse_delay_count_mask;
68 	u32 coarse_ref_count_mask;
69 
70 	u32 reg_fine_offset;
71 	u32 fine_delay_count_mask;
72 	u32 fine_ref_count_mask;
73 
74 	u32 reg_global_lock_offset;
75 	u32 global_lock_mask;
76 	u32 global_unlock_val;
77 	u32 global_lock_val;
78 
79 	u32 reg_start_offset;
80 	u32 reg_nr_per_pin;
81 
82 	struct regmap_config *regmap_config;
83 };
84 
85 /**
86  * struct ti_iodelay_reg_values - Computed io_reg configuration values (see TRM)
87  * @coarse_ref_count: Coarse reference count
88  * @coarse_delay_count: Coarse delay count
89  * @fine_ref_count: Fine reference count
90  * @fine_delay_count: Fine Delay count
91  * @ref_clk_period: Reference Clock period
92  * @cdpe: Coarse delay parameter
93  * @fdpe: Fine delay parameter
94  */
95 struct ti_iodelay_reg_values {
96 	u16 coarse_ref_count;
97 	u16 coarse_delay_count;
98 
99 	u16 fine_ref_count;
100 	u16 fine_delay_count;
101 
102 	u16 ref_clk_period;
103 
104 	u32 cdpe;
105 	u32 fdpe;
106 };
107 
108 /**
109  * struct ti_iodelay_cfg - Description of each configuration parameters
110  * @offset: Configuration register offset
111  * @a_delay: Agnostic Delay (in ps)
112  * @g_delay: Gnostic Delay (in ps)
113  */
114 struct ti_iodelay_cfg {
115 	u16 offset;
116 	u16 a_delay;
117 	u16 g_delay;
118 };
119 
120 /**
121  * struct ti_iodelay_pingroup - Structure that describes one group
122  * @cfg: configuration array for the pin (from dt)
123  * @ncfg: number of configuration values allocated
124  * @config: pinconf "Config" - currently a dummy value
125  */
126 struct ti_iodelay_pingroup {
127 	struct ti_iodelay_cfg *cfg;
128 	int ncfg;
129 	unsigned long config;
130 };
131 
132 /**
133  * struct ti_iodelay_device - Represents information for a iodelay instance
134  * @dev: Device pointer
135  * @phys_base: Physical address base of the iodelay device
136  * @reg_base: Virtual address base of the iodelay device
137  * @regmap: Regmap for this iodelay instance
138  * @pctl: Pinctrl device
139  * @desc: pinctrl descriptor for pctl
140  * @pa: pinctrl pin wise description
141  * @reg_data: Register definition data for the IODelay instance
142  * @reg_init_conf_values: Initial configuration values.
143  */
144 struct ti_iodelay_device {
145 	struct device *dev;
146 	unsigned long phys_base;
147 	void __iomem *reg_base;
148 	struct regmap *regmap;
149 
150 	struct pinctrl_dev *pctl;
151 	struct pinctrl_desc desc;
152 	struct pinctrl_pin_desc *pa;
153 
154 	const struct ti_iodelay_reg_data *reg_data;
155 	struct ti_iodelay_reg_values reg_init_conf_values;
156 };
157 
158 /**
159  * ti_iodelay_extract() - extract bits for a field
160  * @val: Register value
161  * @mask: Mask
162  *
163  * Return: extracted value which is appropriately shifted
164  */
165 static inline u32 ti_iodelay_extract(u32 val, u32 mask)
166 {
167 	return (val & mask) >> __ffs(mask);
168 }
169 
170 /**
171  * ti_iodelay_compute_dpe() - Compute equation for delay parameter
172  * @period: Period to use
173  * @ref: Reference Count
174  * @delay: Delay count
175  * @delay_m: Delay multiplier
176  *
177  * Return: Computed delay parameter
178  */
179 static inline u32 ti_iodelay_compute_dpe(u16 period, u16 ref, u16 delay,
180 					 u16 delay_m)
181 {
182 	u64 m, d;
183 
184 	/* Handle overflow conditions */
185 	m = 10 * (u64)period * (u64)ref;
186 	d = 2 * (u64)delay * (u64)delay_m;
187 
188 	/* Truncate result back to 32 bits */
189 	return div64_u64(m, d);
190 }
191 
192 /**
193  * ti_iodelay_pinconf_set() - Configure the pin configuration
194  * @iod: iodelay device
195  * @cfg: Configuration
196  *
197  * Update the configuration register as per TRM and lockup once done.
198  * *IMPORTANT NOTE* SoC TRM does recommend doing iodelay programmation only
199  * while in Isolation. But, then, isolation also implies that every pin
200  * on the SoC (including DDR) will be isolated out. The only benefit being
201  * a glitchless configuration, However, the intent of this driver is purely
202  * to support a "glitchy" configuration where applicable.
203  *
204  * Return: 0 in case of success, else appropriate error value
205  */
206 static int ti_iodelay_pinconf_set(struct ti_iodelay_device *iod,
207 				  struct ti_iodelay_cfg *cfg)
208 {
209 	const struct ti_iodelay_reg_data *reg = iod->reg_data;
210 	struct ti_iodelay_reg_values *ival = &iod->reg_init_conf_values;
211 	struct device *dev = iod->dev;
212 	u32 g_delay_coarse, g_delay_fine;
213 	u32 a_delay_coarse, a_delay_fine;
214 	u32 c_elements, f_elements;
215 	u32 total_delay;
216 	u32 reg_mask, reg_val, tmp_val;
217 	int r;
218 
219 	/* NOTE: Truncation is expected in all division below */
220 	g_delay_coarse = cfg->g_delay / 920;
221 	g_delay_fine = ((cfg->g_delay % 920) * 10) / 60;
222 
223 	a_delay_coarse = cfg->a_delay / ival->cdpe;
224 	a_delay_fine = ((cfg->a_delay % ival->cdpe) * 10) / ival->fdpe;
225 
226 	c_elements = g_delay_coarse + a_delay_coarse;
227 	f_elements = (g_delay_fine + a_delay_fine) / 10;
228 
229 	if (f_elements > 22) {
230 		total_delay = c_elements * ival->cdpe + f_elements * ival->fdpe;
231 		c_elements = total_delay / ival->cdpe;
232 		f_elements = (total_delay % ival->cdpe) / ival->fdpe;
233 	}
234 
235 	reg_mask = reg->signature_mask;
236 	reg_val = reg->signature_value << __ffs(reg->signature_mask);
237 
238 	reg_mask |= reg->binary_data_coarse_mask;
239 	tmp_val = c_elements << __ffs(reg->binary_data_coarse_mask);
240 	if (tmp_val & ~reg->binary_data_coarse_mask) {
241 		dev_err(dev, "Masking overflow of coarse elements %08x\n",
242 			tmp_val);
243 		tmp_val &= reg->binary_data_coarse_mask;
244 	}
245 	reg_val |= tmp_val;
246 
247 	reg_mask |= reg->binary_data_fine_mask;
248 	tmp_val = f_elements << __ffs(reg->binary_data_fine_mask);
249 	if (tmp_val & ~reg->binary_data_fine_mask) {
250 		dev_err(dev, "Masking overflow of fine elements %08x\n",
251 			tmp_val);
252 		tmp_val &= reg->binary_data_fine_mask;
253 	}
254 	reg_val |= tmp_val;
255 
256 	/*
257 	 * NOTE: we leave the iodelay values unlocked - this is to work around
258 	 * situations such as those found with mmc mode change.
259 	 * However, this leaves open any unwarranted changes to padconf register
260 	 * impacting iodelay configuration. Use with care!
261 	 */
262 	reg_mask |= reg->lock_mask;
263 	reg_val |= reg->unlock_val << __ffs(reg->lock_mask);
264 	r = regmap_update_bits(iod->regmap, cfg->offset, reg_mask, reg_val);
265 
266 	dev_dbg(dev, "Set reg 0x%x Delay(a: %d g: %d), Elements(C=%d F=%d)0x%x\n",
267 		cfg->offset, cfg->a_delay, cfg->g_delay, c_elements,
268 		f_elements, reg_val);
269 
270 	return r;
271 }
272 
273 /**
274  * ti_iodelay_pinconf_init_dev() - Initialize IODelay device
275  * @iod: iodelay device
276  *
277  * Unlocks the iodelay region, computes the common parameters
278  *
279  * Return: 0 in case of success, else appropriate error value
280  */
281 static int ti_iodelay_pinconf_init_dev(struct ti_iodelay_device *iod)
282 {
283 	const struct ti_iodelay_reg_data *reg = iod->reg_data;
284 	struct device *dev = iod->dev;
285 	struct ti_iodelay_reg_values *ival = &iod->reg_init_conf_values;
286 	u32 val;
287 	int r;
288 
289 	/* unlock the iodelay region */
290 	r = regmap_update_bits(iod->regmap, reg->reg_global_lock_offset,
291 			       reg->global_lock_mask, reg->global_unlock_val);
292 	if (r)
293 		return r;
294 
295 	/* Read up Recalibration sequence done by bootloader */
296 	r = regmap_read(iod->regmap, reg->reg_refclk_offset, &val);
297 	if (r)
298 		return r;
299 	ival->ref_clk_period = ti_iodelay_extract(val, reg->refclk_period_mask);
300 	dev_dbg(dev, "refclk_period=0x%04x\n", ival->ref_clk_period);
301 
302 	r = regmap_read(iod->regmap, reg->reg_coarse_offset, &val);
303 	if (r)
304 		return r;
305 	ival->coarse_ref_count =
306 	    ti_iodelay_extract(val, reg->coarse_ref_count_mask);
307 	ival->coarse_delay_count =
308 	    ti_iodelay_extract(val, reg->coarse_delay_count_mask);
309 	if (!ival->coarse_delay_count) {
310 		dev_err(dev, "Invalid Coarse delay count (0) (reg=0x%08x)\n",
311 			val);
312 		return -EINVAL;
313 	}
314 	ival->cdpe = ti_iodelay_compute_dpe(ival->ref_clk_period,
315 					    ival->coarse_ref_count,
316 					    ival->coarse_delay_count, 88);
317 	if (!ival->cdpe) {
318 		dev_err(dev, "Invalid cdpe computed params = %d %d %d\n",
319 			ival->ref_clk_period, ival->coarse_ref_count,
320 			ival->coarse_delay_count);
321 		return -EINVAL;
322 	}
323 	dev_dbg(iod->dev, "coarse: ref=0x%04x delay=0x%04x cdpe=0x%08x\n",
324 		ival->coarse_ref_count, ival->coarse_delay_count, ival->cdpe);
325 
326 	r = regmap_read(iod->regmap, reg->reg_fine_offset, &val);
327 	if (r)
328 		return r;
329 	ival->fine_ref_count =
330 	    ti_iodelay_extract(val, reg->fine_ref_count_mask);
331 	ival->fine_delay_count =
332 	    ti_iodelay_extract(val, reg->fine_delay_count_mask);
333 	if (!ival->fine_delay_count) {
334 		dev_err(dev, "Invalid Fine delay count (0) (reg=0x%08x)\n",
335 			val);
336 		return -EINVAL;
337 	}
338 	ival->fdpe = ti_iodelay_compute_dpe(ival->ref_clk_period,
339 					    ival->fine_ref_count,
340 					    ival->fine_delay_count, 264);
341 	if (!ival->fdpe) {
342 		dev_err(dev, "Invalid fdpe(0) computed params = %d %d %d\n",
343 			ival->ref_clk_period, ival->fine_ref_count,
344 			ival->fine_delay_count);
345 		return -EINVAL;
346 	}
347 	dev_dbg(iod->dev, "fine: ref=0x%04x delay=0x%04x fdpe=0x%08x\n",
348 		ival->fine_ref_count, ival->fine_delay_count, ival->fdpe);
349 
350 	return 0;
351 }
352 
353 /**
354  * ti_iodelay_pinconf_deinit_dev() - deinit the iodelay device
355  * @iod:	IODelay device
356  *
357  * Deinitialize the IODelay device (basically just lock the region back up.
358  */
359 static void ti_iodelay_pinconf_deinit_dev(struct ti_iodelay_device *iod)
360 {
361 	const struct ti_iodelay_reg_data *reg = iod->reg_data;
362 
363 	/* lock the iodelay region back again */
364 	regmap_update_bits(iod->regmap, reg->reg_global_lock_offset,
365 			   reg->global_lock_mask, reg->global_lock_val);
366 }
367 
368 /**
369  * ti_iodelay_get_pingroup() - Find the group mapped by a group selector
370  * @iod: iodelay device
371  * @selector: Group Selector
372  *
373  * Return: Corresponding group representing group selector
374  */
375 static struct ti_iodelay_pingroup *
376 ti_iodelay_get_pingroup(struct ti_iodelay_device *iod, unsigned int selector)
377 {
378 	struct group_desc *g;
379 
380 	g = pinctrl_generic_get_group(iod->pctl, selector);
381 	if (!g) {
382 		dev_err(iod->dev, "%s could not find pingroup %i\n", __func__,
383 			selector);
384 
385 		return NULL;
386 	}
387 
388 	return g->data;
389 }
390 
391 /**
392  * ti_iodelay_offset_to_pin() - get a pin index based on the register offset
393  * @iod: iodelay driver instance
394  * @offset: register offset from the base
395  */
396 static int ti_iodelay_offset_to_pin(struct ti_iodelay_device *iod,
397 				    unsigned int offset)
398 {
399 	const struct ti_iodelay_reg_data *r = iod->reg_data;
400 	unsigned int index;
401 
402 	if (offset > r->regmap_config->max_register) {
403 		dev_err(iod->dev, "mux offset out of range: 0x%x (0x%x)\n",
404 			offset, r->regmap_config->max_register);
405 		return -EINVAL;
406 	}
407 
408 	index = (offset - r->reg_start_offset) / r->regmap_config->reg_stride;
409 	index /= r->reg_nr_per_pin;
410 
411 	return index;
412 }
413 
414 /**
415  * ti_iodelay_node_iterator() - Iterate iodelay node
416  * @pctldev: Pin controller driver
417  * @np: Device node
418  * @pinctrl_spec: Parsed arguments from device tree
419  * @pins: Array of pins in the pin group
420  * @pin_index: Pin index in the pin array
421  * @data: Pin controller driver specific data
422  *
423  */
424 static int ti_iodelay_node_iterator(struct pinctrl_dev *pctldev,
425 				    struct device_node *np,
426 				    const struct of_phandle_args *pinctrl_spec,
427 				    int *pins, int pin_index, void *data)
428 {
429 	struct ti_iodelay_device *iod;
430 	struct ti_iodelay_cfg *cfg = data;
431 	const struct ti_iodelay_reg_data *r;
432 	struct pinctrl_pin_desc *pd;
433 	int pin;
434 
435 	iod = pinctrl_dev_get_drvdata(pctldev);
436 	if (!iod)
437 		return -EINVAL;
438 
439 	r = iod->reg_data;
440 
441 	if (pinctrl_spec->args_count < r->reg_nr_per_pin) {
442 		dev_err(iod->dev, "invalid args_count for spec: %i\n",
443 			pinctrl_spec->args_count);
444 
445 		return -EINVAL;
446 	}
447 
448 	/* Index plus two value cells */
449 	cfg[pin_index].offset = pinctrl_spec->args[0];
450 	cfg[pin_index].a_delay = pinctrl_spec->args[1] & 0xffff;
451 	cfg[pin_index].g_delay = pinctrl_spec->args[2] & 0xffff;
452 
453 	pin = ti_iodelay_offset_to_pin(iod, cfg[pin_index].offset);
454 	if (pin < 0) {
455 		dev_err(iod->dev, "could not add functions for %pOFn %ux\n",
456 			np, cfg[pin_index].offset);
457 		return -ENODEV;
458 	}
459 	pins[pin_index] = pin;
460 
461 	pd = &iod->pa[pin];
462 	pd->drv_data = &cfg[pin_index];
463 
464 	dev_dbg(iod->dev, "%pOFn offset=%x a_delay = %d g_delay = %d\n",
465 		np, cfg[pin_index].offset, cfg[pin_index].a_delay,
466 		cfg[pin_index].g_delay);
467 
468 	return 0;
469 }
470 
471 /**
472  * ti_iodelay_dt_node_to_map() - Map a device tree node to appropriate group
473  * @pctldev: pinctrl device representing IODelay device
474  * @np: Node Pointer (device tree)
475  * @map: Pinctrl Map returned back to pinctrl framework
476  * @num_maps: Number of maps (1)
477  *
478  * Maps the device tree description into a group of configuration parameters
479  * for iodelay block entry.
480  *
481  * Return: 0 in case of success, else appropriate error value
482  */
483 static int ti_iodelay_dt_node_to_map(struct pinctrl_dev *pctldev,
484 				     struct device_node *np,
485 				     struct pinctrl_map **map,
486 				     unsigned int *num_maps)
487 {
488 	struct ti_iodelay_device *iod;
489 	struct ti_iodelay_cfg *cfg;
490 	struct ti_iodelay_pingroup *g;
491 	const char *name = "pinctrl-pin-array";
492 	int rows, *pins, error = -EINVAL, i;
493 
494 	iod = pinctrl_dev_get_drvdata(pctldev);
495 	if (!iod)
496 		return -EINVAL;
497 
498 	rows = pinctrl_count_index_with_args(np, name);
499 	if (rows < 0)
500 		return rows;
501 
502 	*map = devm_kzalloc(iod->dev, sizeof(**map), GFP_KERNEL);
503 	if (!*map)
504 		return -ENOMEM;
505 	*num_maps = 0;
506 
507 	g = devm_kzalloc(iod->dev, sizeof(*g), GFP_KERNEL);
508 	if (!g) {
509 		error = -ENOMEM;
510 		goto free_map;
511 	}
512 
513 	pins = devm_kcalloc(iod->dev, rows, sizeof(*pins), GFP_KERNEL);
514 	if (!pins) {
515 		error = -ENOMEM;
516 		goto free_group;
517 	}
518 
519 	cfg = devm_kcalloc(iod->dev, rows, sizeof(*cfg), GFP_KERNEL);
520 	if (!cfg) {
521 		error = -ENOMEM;
522 		goto free_pins;
523 	}
524 
525 	for (i = 0; i < rows; i++) {
526 		struct of_phandle_args pinctrl_spec;
527 
528 		error = pinctrl_parse_index_with_args(np, name, i,
529 						      &pinctrl_spec);
530 		if (error)
531 			goto free_data;
532 
533 		error = ti_iodelay_node_iterator(pctldev, np, &pinctrl_spec,
534 						 pins, i, cfg);
535 		if (error)
536 			goto free_data;
537 	}
538 
539 	g->cfg = cfg;
540 	g->ncfg = i;
541 	g->config = PIN_CONFIG_END;
542 
543 	error = pinctrl_generic_add_group(iod->pctl, np->name, pins, i, g);
544 	if (error < 0)
545 		goto free_data;
546 
547 	(*map)->type = PIN_MAP_TYPE_CONFIGS_GROUP;
548 	(*map)->data.configs.group_or_pin = np->name;
549 	(*map)->data.configs.configs = &g->config;
550 	(*map)->data.configs.num_configs = 1;
551 	*num_maps = 1;
552 
553 	return 0;
554 
555 free_data:
556 	devm_kfree(iod->dev, cfg);
557 free_pins:
558 	devm_kfree(iod->dev, pins);
559 free_group:
560 	devm_kfree(iod->dev, g);
561 free_map:
562 	devm_kfree(iod->dev, *map);
563 
564 	return error;
565 }
566 
567 /**
568  * ti_iodelay_pinconf_group_get() - Get the group configuration
569  * @pctldev: pinctrl device representing IODelay device
570  * @selector: Group selector
571  * @config: Configuration returned
572  *
573  * Return: The configuration if the group is valid, else returns -EINVAL
574  */
575 static int ti_iodelay_pinconf_group_get(struct pinctrl_dev *pctldev,
576 					unsigned int selector,
577 					unsigned long *config)
578 {
579 	struct ti_iodelay_device *iod;
580 	struct ti_iodelay_pingroup *group;
581 
582 	iod = pinctrl_dev_get_drvdata(pctldev);
583 	group = ti_iodelay_get_pingroup(iod, selector);
584 
585 	if (!group)
586 		return -EINVAL;
587 
588 	*config = group->config;
589 	return 0;
590 }
591 
592 /**
593  * ti_iodelay_pinconf_group_set() - Configure the groups of pins
594  * @pctldev: pinctrl device representing IODelay device
595  * @selector: Group selector
596  * @configs: Configurations
597  * @num_configs: Number of configurations
598  *
599  * Return: 0 if all went fine, else appropriate error value.
600  */
601 static int ti_iodelay_pinconf_group_set(struct pinctrl_dev *pctldev,
602 					unsigned int selector,
603 					unsigned long *configs,
604 					unsigned int num_configs)
605 {
606 	struct ti_iodelay_device *iod;
607 	struct device *dev;
608 	struct ti_iodelay_pingroup *group;
609 	int i;
610 
611 	iod = pinctrl_dev_get_drvdata(pctldev);
612 	dev = iod->dev;
613 	group = ti_iodelay_get_pingroup(iod, selector);
614 
615 	if (num_configs != 1) {
616 		dev_err(dev, "Unsupported number of configurations %d\n",
617 			num_configs);
618 		return -EINVAL;
619 	}
620 
621 	if (*configs != PIN_CONFIG_END) {
622 		dev_err(dev, "Unsupported configuration\n");
623 		return -EINVAL;
624 	}
625 
626 	for (i = 0; i < group->ncfg; i++) {
627 		if (ti_iodelay_pinconf_set(iod, &group->cfg[i]))
628 			return -ENOTSUPP;
629 	}
630 
631 	return 0;
632 }
633 
634 #ifdef CONFIG_DEBUG_FS
635 /**
636  * ti_iodelay_pin_to_offset() - get pin register offset based on the pin index
637  * @iod: iodelay driver instance
638  * @selector: Pin index
639  */
640 static unsigned int ti_iodelay_pin_to_offset(struct ti_iodelay_device *iod,
641 					     unsigned int selector)
642 {
643 	const struct ti_iodelay_reg_data *r = iod->reg_data;
644 	unsigned int offset;
645 
646 	offset = selector * r->regmap_config->reg_stride;
647 	offset *= r->reg_nr_per_pin;
648 	offset += r->reg_start_offset;
649 
650 	return offset;
651 }
652 
653 static void ti_iodelay_pin_dbg_show(struct pinctrl_dev *pctldev,
654 				    struct seq_file *s,
655 				    unsigned int pin)
656 {
657 	struct ti_iodelay_device *iod;
658 	struct pinctrl_pin_desc *pd;
659 	struct ti_iodelay_cfg *cfg;
660 	const struct ti_iodelay_reg_data *r;
661 	unsigned long offset;
662 	u32 in, oen, out;
663 
664 	iod = pinctrl_dev_get_drvdata(pctldev);
665 	r = iod->reg_data;
666 
667 	offset = ti_iodelay_pin_to_offset(iod, pin);
668 	pd = &iod->pa[pin];
669 	cfg = pd->drv_data;
670 
671 	regmap_read(iod->regmap, offset, &in);
672 	regmap_read(iod->regmap, offset + r->regmap_config->reg_stride, &oen);
673 	regmap_read(iod->regmap, offset + r->regmap_config->reg_stride * 2,
674 		    &out);
675 
676 	seq_printf(s, "%lx a: %i g: %i (%08x %08x %08x) %s ",
677 		   iod->phys_base + offset,
678 		   cfg ? cfg->a_delay : -1,
679 		   cfg ? cfg->g_delay : -1,
680 		   in, oen, out, DRIVER_NAME);
681 }
682 
683 /**
684  * ti_iodelay_pinconf_group_dbg_show() - show the group information
685  * @pctldev: Show the group information
686  * @s: Sequence file
687  * @selector: Group selector
688  *
689  * Provide the configuration information of the selected group
690  */
691 static void ti_iodelay_pinconf_group_dbg_show(struct pinctrl_dev *pctldev,
692 					      struct seq_file *s,
693 					      unsigned int selector)
694 {
695 	struct ti_iodelay_device *iod;
696 	struct ti_iodelay_pingroup *group;
697 	int i;
698 
699 	iod = pinctrl_dev_get_drvdata(pctldev);
700 	group = ti_iodelay_get_pingroup(iod, selector);
701 	if (!group)
702 		return;
703 
704 	for (i = 0; i < group->ncfg; i++) {
705 		struct ti_iodelay_cfg *cfg;
706 		u32 reg = 0;
707 
708 		cfg = &group->cfg[i];
709 		regmap_read(iod->regmap, cfg->offset, &reg);
710 		seq_printf(s, "\n\t0x%08x = 0x%08x (%3d, %3d)",
711 			cfg->offset, reg, cfg->a_delay, cfg->g_delay);
712 	}
713 }
714 #endif
715 
716 static const struct pinctrl_ops ti_iodelay_pinctrl_ops = {
717 	.get_groups_count = pinctrl_generic_get_group_count,
718 	.get_group_name = pinctrl_generic_get_group_name,
719 	.get_group_pins = pinctrl_generic_get_group_pins,
720 #ifdef CONFIG_DEBUG_FS
721 	.pin_dbg_show = ti_iodelay_pin_dbg_show,
722 #endif
723 	.dt_node_to_map = ti_iodelay_dt_node_to_map,
724 };
725 
726 static const struct pinconf_ops ti_iodelay_pinctrl_pinconf_ops = {
727 	.pin_config_group_get = ti_iodelay_pinconf_group_get,
728 	.pin_config_group_set = ti_iodelay_pinconf_group_set,
729 #ifdef CONFIG_DEBUG_FS
730 	.pin_config_group_dbg_show = ti_iodelay_pinconf_group_dbg_show,
731 #endif
732 };
733 
734 /**
735  * ti_iodelay_alloc_pins() - Allocate structures needed for pins for iodelay
736  * @dev: Device pointer
737  * @iod: iodelay device
738  * @base_phy: Base Physical Address
739  *
740  * Return: 0 if all went fine, else appropriate error value.
741  */
742 static int ti_iodelay_alloc_pins(struct device *dev,
743 				 struct ti_iodelay_device *iod, u32 base_phy)
744 {
745 	const struct ti_iodelay_reg_data *r = iod->reg_data;
746 	struct pinctrl_pin_desc *pin;
747 	u32 phy_reg;
748 	int nr_pins, i;
749 
750 	nr_pins = ti_iodelay_offset_to_pin(iod, r->regmap_config->max_register);
751 	dev_dbg(dev, "Allocating %i pins\n", nr_pins);
752 
753 	iod->pa = devm_kcalloc(dev, nr_pins, sizeof(*iod->pa), GFP_KERNEL);
754 	if (!iod->pa)
755 		return -ENOMEM;
756 
757 	iod->desc.pins = iod->pa;
758 	iod->desc.npins = nr_pins;
759 
760 	phy_reg = r->reg_start_offset + base_phy;
761 
762 	for (i = 0; i < nr_pins; i++, phy_reg += 4) {
763 		pin = &iod->pa[i];
764 		pin->number = i;
765 	}
766 
767 	return 0;
768 }
769 
770 static struct regmap_config dra7_iodelay_regmap_config = {
771 	.reg_bits = 32,
772 	.reg_stride = 4,
773 	.val_bits = 32,
774 	.max_register = 0xd1c,
775 };
776 
777 static struct ti_iodelay_reg_data dra7_iodelay_data = {
778 	.signature_mask = 0x0003f000,
779 	.signature_value = 0x29,
780 	.lock_mask = 0x00000400,
781 	.lock_val = 1,
782 	.unlock_val = 0,
783 	.binary_data_coarse_mask = 0x000003e0,
784 	.binary_data_fine_mask = 0x0000001f,
785 
786 	.reg_refclk_offset = 0x14,
787 	.refclk_period_mask = 0xffff,
788 
789 	.reg_coarse_offset = 0x18,
790 	.coarse_delay_count_mask = 0xffff0000,
791 	.coarse_ref_count_mask = 0x0000ffff,
792 
793 	.reg_fine_offset = 0x1C,
794 	.fine_delay_count_mask = 0xffff0000,
795 	.fine_ref_count_mask = 0x0000ffff,
796 
797 	.reg_global_lock_offset = 0x2c,
798 	.global_lock_mask = 0x0000ffff,
799 	.global_unlock_val = 0x0000aaaa,
800 	.global_lock_val = 0x0000aaab,
801 
802 	.reg_start_offset = 0x30,
803 	.reg_nr_per_pin = 3,
804 	.regmap_config = &dra7_iodelay_regmap_config,
805 };
806 
807 static const struct of_device_id ti_iodelay_of_match[] = {
808 	{.compatible = "ti,dra7-iodelay", .data = &dra7_iodelay_data},
809 	{ /* Hopefully no more.. */ },
810 };
811 MODULE_DEVICE_TABLE(of, ti_iodelay_of_match);
812 
813 /**
814  * ti_iodelay_probe() - Standard probe
815  * @pdev: platform device
816  *
817  * Return: 0 if all went fine, else appropriate error value.
818  */
819 static int ti_iodelay_probe(struct platform_device *pdev)
820 {
821 	struct device *dev = &pdev->dev;
822 	struct device_node *np = of_node_get(dev->of_node);
823 	const struct of_device_id *match;
824 	struct resource *res;
825 	struct ti_iodelay_device *iod;
826 	int ret = 0;
827 
828 	if (!np) {
829 		ret = -EINVAL;
830 		dev_err(dev, "No OF node\n");
831 		goto exit_out;
832 	}
833 
834 	match = of_match_device(ti_iodelay_of_match, dev);
835 	if (!match) {
836 		ret = -EINVAL;
837 		dev_err(dev, "No DATA match\n");
838 		goto exit_out;
839 	}
840 
841 	iod = devm_kzalloc(dev, sizeof(*iod), GFP_KERNEL);
842 	if (!iod) {
843 		ret = -ENOMEM;
844 		goto exit_out;
845 	}
846 	iod->dev = dev;
847 	iod->reg_data = match->data;
848 
849 	/* So far We can assume there is only 1 bank of registers */
850 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
851 	if (!res) {
852 		dev_err(dev, "Missing MEM resource\n");
853 		ret = -ENODEV;
854 		goto exit_out;
855 	}
856 
857 	iod->phys_base = res->start;
858 	iod->reg_base = devm_ioremap_resource(dev, res);
859 	if (IS_ERR(iod->reg_base)) {
860 		ret = PTR_ERR(iod->reg_base);
861 		goto exit_out;
862 	}
863 
864 	iod->regmap = devm_regmap_init_mmio(dev, iod->reg_base,
865 					    iod->reg_data->regmap_config);
866 	if (IS_ERR(iod->regmap)) {
867 		dev_err(dev, "Regmap MMIO init failed.\n");
868 		ret = PTR_ERR(iod->regmap);
869 		goto exit_out;
870 	}
871 
872 	ret = ti_iodelay_pinconf_init_dev(iod);
873 	if (ret)
874 		goto exit_out;
875 
876 	ret = ti_iodelay_alloc_pins(dev, iod, res->start);
877 	if (ret)
878 		goto exit_out;
879 
880 	iod->desc.pctlops = &ti_iodelay_pinctrl_ops;
881 	/* no pinmux ops - we are pinconf */
882 	iod->desc.confops = &ti_iodelay_pinctrl_pinconf_ops;
883 	iod->desc.name = dev_name(dev);
884 	iod->desc.owner = THIS_MODULE;
885 
886 	ret = pinctrl_register_and_init(&iod->desc, dev, iod, &iod->pctl);
887 	if (ret) {
888 		dev_err(dev, "Failed to register pinctrl\n");
889 		goto exit_out;
890 	}
891 
892 	platform_set_drvdata(pdev, iod);
893 
894 	return pinctrl_enable(iod->pctl);
895 
896 exit_out:
897 	of_node_put(np);
898 	return ret;
899 }
900 
901 /**
902  * ti_iodelay_remove() - standard remove
903  * @pdev: platform device
904  *
905  * Return: 0 if all went fine, else appropriate error value.
906  */
907 static int ti_iodelay_remove(struct platform_device *pdev)
908 {
909 	struct ti_iodelay_device *iod = platform_get_drvdata(pdev);
910 
911 	if (!iod)
912 		return 0;
913 
914 	if (iod->pctl)
915 		pinctrl_unregister(iod->pctl);
916 
917 	ti_iodelay_pinconf_deinit_dev(iod);
918 
919 	/* Expect other allocations to be freed by devm */
920 
921 	return 0;
922 }
923 
924 static struct platform_driver ti_iodelay_driver = {
925 	.probe = ti_iodelay_probe,
926 	.remove = ti_iodelay_remove,
927 	.driver = {
928 		   .name = DRIVER_NAME,
929 		   .of_match_table = ti_iodelay_of_match,
930 	},
931 };
932 module_platform_driver(ti_iodelay_driver);
933 
934 MODULE_AUTHOR("Texas Instruments, Inc.");
935 MODULE_DESCRIPTION("Pinconf driver for TI's IO Delay module");
936 MODULE_LICENSE("GPL v2");
937