1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Combined GPIO and pin controller support for Renesas RZ/A2 (R7S9210) SoC
4  *
5  * Copyright (C) 2018 Chris Brandt
6  */
7 
8 /*
9  * This pin controller/gpio combined driver supports Renesas devices of RZ/A2
10  * family.
11  */
12 
13 #include <linux/bitops.h>
14 #include <linux/gpio/driver.h>
15 #include <linux/io.h>
16 #include <linux/module.h>
17 #include <linux/of_device.h>
18 #include <linux/pinctrl/pinmux.h>
19 
20 #include "../core.h"
21 #include "../pinmux.h"
22 
23 #define DRIVER_NAME		"pinctrl-rza2"
24 
25 #define RZA2_PINS_PER_PORT	8
26 #define RZA2_PIN_ID_TO_PORT(id)	((id) / RZA2_PINS_PER_PORT)
27 #define RZA2_PIN_ID_TO_PIN(id)	((id) % RZA2_PINS_PER_PORT)
28 
29 /*
30  * Use 16 lower bits [15:0] for pin identifier
31  * Use 16 higher bits [31:16] for pin mux function
32  */
33 #define MUX_PIN_ID_MASK		GENMASK(15, 0)
34 #define MUX_FUNC_MASK		GENMASK(31, 16)
35 #define MUX_FUNC_OFFS		16
36 #define MUX_FUNC(pinconf)	((pinconf & MUX_FUNC_MASK) >> MUX_FUNC_OFFS)
37 
38 static const char port_names[] = "0123456789ABCDEFGHJKLM";
39 
40 struct rza2_pinctrl_priv {
41 	struct device *dev;
42 	void __iomem *base;
43 
44 	struct pinctrl_pin_desc *pins;
45 	struct pinctrl_desc desc;
46 	struct pinctrl_dev *pctl;
47 	struct pinctrl_gpio_range gpio_range;
48 	int npins;
49 };
50 
51 #define RZA2_PDR(port)		(0x0000 + (port) * 2)	/* Direction 16-bit */
52 #define RZA2_PODR(port)		(0x0040 + (port))	/* Output Data 8-bit */
53 #define RZA2_PIDR(port)		(0x0060 + (port))	/* Input Data 8-bit */
54 #define RZA2_PMR(port)		(0x0080 + (port))	/* Mode 8-bit */
55 #define RZA2_DSCR(port)		(0x0140 + (port) * 2)	/* Drive 16-bit */
56 #define RZA2_PFS(port, pin)	(0x0200 + ((port) * 8) + (pin))	/* Fnct 8-bit */
57 
58 #define RZA2_PWPR		0x02ff	/* Write Protect 8-bit */
59 #define RZA2_PFENET		0x0820	/* Ethernet Pins 8-bit */
60 #define RZA2_PPOC		0x0900	/* Dedicated Pins 32-bit */
61 #define RZA2_PHMOMO		0x0980	/* Peripheral Pins 32-bit */
62 #define RZA2_PCKIO		0x09d0	/* CKIO Drive 8-bit */
63 
64 #define RZA2_PDR_INPUT		0x02
65 #define RZA2_PDR_OUTPUT		0x03
66 #define RZA2_PDR_MASK		0x03
67 
68 #define PWPR_B0WI		BIT(7)	/* Bit Write Disable */
69 #define PWPR_PFSWE		BIT(6)	/* PFS Register Write Enable */
70 #define PFS_ISEL		BIT(6)	/* Interrupt Select */
71 
72 static void rza2_set_pin_function(void __iomem *pfc_base, u8 port, u8 pin,
73 				  u8 func)
74 {
75 	u16 mask16;
76 	u16 reg16;
77 	u8 reg8;
78 
79 	/* Set pin to 'Non-use (Hi-z input protection)'  */
80 	reg16 = readw(pfc_base + RZA2_PDR(port));
81 	mask16 = RZA2_PDR_MASK << (pin * 2);
82 	reg16 &= ~mask16;
83 	writew(reg16, pfc_base + RZA2_PDR(port));
84 
85 	/* Temporarily switch to GPIO */
86 	reg8 = readb(pfc_base + RZA2_PMR(port));
87 	reg8 &= ~BIT(pin);
88 	writeb(reg8, pfc_base + RZA2_PMR(port));
89 
90 	/* PFS Register Write Protect : OFF */
91 	writeb(0x00, pfc_base + RZA2_PWPR);		/* B0WI=0, PFSWE=0 */
92 	writeb(PWPR_PFSWE, pfc_base + RZA2_PWPR);	/* B0WI=0, PFSWE=1 */
93 
94 	/* Set Pin function (interrupt disabled, ISEL=0) */
95 	writeb(func, pfc_base + RZA2_PFS(port, pin));
96 
97 	/* PFS Register Write Protect : ON */
98 	writeb(0x00, pfc_base + RZA2_PWPR);	/* B0WI=0, PFSWE=0 */
99 	writeb(0x80, pfc_base + RZA2_PWPR);	/* B0WI=1, PFSWE=0 */
100 
101 	/* Port Mode  : Peripheral module pin functions */
102 	reg8 = readb(pfc_base + RZA2_PMR(port));
103 	reg8 |= BIT(pin);
104 	writeb(reg8, pfc_base + RZA2_PMR(port));
105 }
106 
107 static void rza2_pin_to_gpio(void __iomem *pfc_base, unsigned int offset,
108 			     u8 dir)
109 {
110 	u8 port = RZA2_PIN_ID_TO_PORT(offset);
111 	u8 pin = RZA2_PIN_ID_TO_PIN(offset);
112 	u16 mask16;
113 	u16 reg16;
114 
115 	reg16 = readw(pfc_base + RZA2_PDR(port));
116 	mask16 = RZA2_PDR_MASK << (pin * 2);
117 	reg16 &= ~mask16;
118 
119 	if (dir)
120 		reg16 |= RZA2_PDR_INPUT << (pin * 2);	/* pin as input */
121 	else
122 		reg16 |= RZA2_PDR_OUTPUT << (pin * 2);	/* pin as output */
123 
124 	writew(reg16, pfc_base + RZA2_PDR(port));
125 }
126 
127 static int rza2_chip_get_direction(struct gpio_chip *chip, unsigned int offset)
128 {
129 	struct rza2_pinctrl_priv *priv = gpiochip_get_data(chip);
130 	u8 port = RZA2_PIN_ID_TO_PORT(offset);
131 	u8 pin = RZA2_PIN_ID_TO_PIN(offset);
132 	u16 reg16;
133 
134 	reg16 = readw(priv->base + RZA2_PDR(port));
135 	reg16 = (reg16 >> (pin * 2)) & RZA2_PDR_MASK;
136 
137 	if (reg16 == RZA2_PDR_OUTPUT)
138 		return GPIO_LINE_DIRECTION_OUT;
139 
140 	if (reg16 == RZA2_PDR_INPUT)
141 		return GPIO_LINE_DIRECTION_IN;
142 
143 	/*
144 	 * This GPIO controller has a default Hi-Z state that is not input or
145 	 * output, so force the pin to input now.
146 	 */
147 	rza2_pin_to_gpio(priv->base, offset, 1);
148 
149 	return GPIO_LINE_DIRECTION_IN;
150 }
151 
152 static int rza2_chip_direction_input(struct gpio_chip *chip,
153 				     unsigned int offset)
154 {
155 	struct rza2_pinctrl_priv *priv = gpiochip_get_data(chip);
156 
157 	rza2_pin_to_gpio(priv->base, offset, 1);
158 
159 	return 0;
160 }
161 
162 static int rza2_chip_get(struct gpio_chip *chip, unsigned int offset)
163 {
164 	struct rza2_pinctrl_priv *priv = gpiochip_get_data(chip);
165 	u8 port = RZA2_PIN_ID_TO_PORT(offset);
166 	u8 pin = RZA2_PIN_ID_TO_PIN(offset);
167 
168 	return !!(readb(priv->base + RZA2_PIDR(port)) & BIT(pin));
169 }
170 
171 static void rza2_chip_set(struct gpio_chip *chip, unsigned int offset,
172 			  int value)
173 {
174 	struct rza2_pinctrl_priv *priv = gpiochip_get_data(chip);
175 	u8 port = RZA2_PIN_ID_TO_PORT(offset);
176 	u8 pin = RZA2_PIN_ID_TO_PIN(offset);
177 	u8 new_value;
178 
179 	new_value = readb(priv->base + RZA2_PODR(port));
180 
181 	if (value)
182 		new_value |= BIT(pin);
183 	else
184 		new_value &= ~BIT(pin);
185 
186 	writeb(new_value, priv->base + RZA2_PODR(port));
187 }
188 
189 static int rza2_chip_direction_output(struct gpio_chip *chip,
190 				      unsigned int offset, int val)
191 {
192 	struct rza2_pinctrl_priv *priv = gpiochip_get_data(chip);
193 
194 	rza2_chip_set(chip, offset, val);
195 	rza2_pin_to_gpio(priv->base, offset, 0);
196 
197 	return 0;
198 }
199 
200 static const char * const rza2_gpio_names[] = {
201 	"P0_0", "P0_1", "P0_2", "P0_3", "P0_4", "P0_5", "P0_6", "P0_7",
202 	"P1_0", "P1_1", "P1_2", "P1_3", "P1_4", "P1_5", "P1_6", "P1_7",
203 	"P2_0", "P2_1", "P2_2", "P2_3", "P2_4", "P2_5", "P2_6", "P2_7",
204 	"P3_0", "P3_1", "P3_2", "P3_3", "P3_4", "P3_5", "P3_6", "P3_7",
205 	"P4_0", "P4_1", "P4_2", "P4_3", "P4_4", "P4_5", "P4_6", "P4_7",
206 	"P5_0", "P5_1", "P5_2", "P5_3", "P5_4", "P5_5", "P5_6", "P5_7",
207 	"P6_0", "P6_1", "P6_2", "P6_3", "P6_4", "P6_5", "P6_6", "P6_7",
208 	"P7_0", "P7_1", "P7_2", "P7_3", "P7_4", "P7_5", "P7_6", "P7_7",
209 	"P8_0", "P8_1", "P8_2", "P8_3", "P8_4", "P8_5", "P8_6", "P8_7",
210 	"P9_0", "P9_1", "P9_2", "P9_3", "P9_4", "P9_5", "P9_6", "P9_7",
211 	"PA_0", "PA_1", "PA_2", "PA_3", "PA_4", "PA_5", "PA_6", "PA_7",
212 	"PB_0", "PB_1", "PB_2", "PB_3", "PB_4", "PB_5", "PB_6", "PB_7",
213 	"PC_0", "PC_1", "PC_2", "PC_3", "PC_4", "PC_5", "PC_6", "PC_7",
214 	"PD_0", "PD_1", "PD_2", "PD_3", "PD_4", "PD_5", "PD_6", "PD_7",
215 	"PE_0", "PE_1", "PE_2", "PE_3", "PE_4", "PE_5", "PE_6", "PE_7",
216 	"PF_0", "PF_1", "PF_2", "PF_3", "PF_4", "PF_5", "PF_6", "PF_7",
217 	"PG_0", "PG_1", "PG_2", "PG_3", "PG_4", "PG_5", "PG_6", "PG_7",
218 	"PH_0", "PH_1", "PH_2", "PH_3", "PH_4", "PH_5", "PH_6", "PH_7",
219 	/* port I does not exist */
220 	"PJ_0", "PJ_1", "PJ_2", "PJ_3", "PJ_4", "PJ_5", "PJ_6", "PJ_7",
221 	"PK_0", "PK_1", "PK_2", "PK_3", "PK_4", "PK_5", "PK_6", "PK_7",
222 	"PL_0", "PL_1", "PL_2", "PL_3", "PL_4", "PL_5", "PL_6", "PL_7",
223 	"PM_0", "PM_1", "PM_2", "PM_3", "PM_4", "PM_5", "PM_6", "PM_7",
224 };
225 
226 static struct gpio_chip chip = {
227 	.names = rza2_gpio_names,
228 	.base = -1,
229 	.get_direction = rza2_chip_get_direction,
230 	.direction_input = rza2_chip_direction_input,
231 	.direction_output = rza2_chip_direction_output,
232 	.get = rza2_chip_get,
233 	.set = rza2_chip_set,
234 };
235 
236 static int rza2_gpio_register(struct rza2_pinctrl_priv *priv)
237 {
238 	struct device_node *np = priv->dev->of_node;
239 	struct of_phandle_args of_args;
240 	int ret;
241 
242 	chip.label = devm_kasprintf(priv->dev, GFP_KERNEL, "%pOFn", np);
243 	chip.parent = priv->dev;
244 	chip.ngpio = priv->npins;
245 
246 	ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3, 0,
247 					       &of_args);
248 	if (ret) {
249 		dev_err(priv->dev, "Unable to parse gpio-ranges\n");
250 		return ret;
251 	}
252 
253 	if ((of_args.args[0] != 0) ||
254 	    (of_args.args[1] != 0) ||
255 	    (of_args.args[2] != priv->npins)) {
256 		dev_err(priv->dev, "gpio-ranges does not match selected SOC\n");
257 		return -EINVAL;
258 	}
259 	priv->gpio_range.id = 0;
260 	priv->gpio_range.pin_base = priv->gpio_range.base = 0;
261 	priv->gpio_range.npins = priv->npins;
262 	priv->gpio_range.name = chip.label;
263 	priv->gpio_range.gc = &chip;
264 
265 	/* Register our gpio chip with gpiolib */
266 	ret = devm_gpiochip_add_data(priv->dev, &chip, priv);
267 	if (ret)
268 		return ret;
269 
270 	/* Register pin range with pinctrl core */
271 	pinctrl_add_gpio_range(priv->pctl, &priv->gpio_range);
272 
273 	dev_dbg(priv->dev, "Registered gpio controller\n");
274 
275 	return 0;
276 }
277 
278 static int rza2_pinctrl_register(struct rza2_pinctrl_priv *priv)
279 {
280 	struct pinctrl_pin_desc *pins;
281 	unsigned int i;
282 	int ret;
283 
284 	pins = devm_kcalloc(priv->dev, priv->npins, sizeof(*pins), GFP_KERNEL);
285 	if (!pins)
286 		return -ENOMEM;
287 
288 	priv->pins = pins;
289 	priv->desc.pins = pins;
290 	priv->desc.npins = priv->npins;
291 
292 	for (i = 0; i < priv->npins; i++) {
293 		pins[i].number = i;
294 		pins[i].name = rza2_gpio_names[i];
295 	}
296 
297 	ret = devm_pinctrl_register_and_init(priv->dev, &priv->desc, priv,
298 					     &priv->pctl);
299 	if (ret) {
300 		dev_err(priv->dev, "pinctrl registration failed\n");
301 		return ret;
302 	}
303 
304 	ret = pinctrl_enable(priv->pctl);
305 	if (ret) {
306 		dev_err(priv->dev, "pinctrl enable failed\n");
307 		return ret;
308 	}
309 
310 	ret = rza2_gpio_register(priv);
311 	if (ret) {
312 		dev_err(priv->dev, "GPIO registration failed\n");
313 		return ret;
314 	}
315 
316 	return 0;
317 }
318 
319 /*
320  * For each DT node, create a single pin mapping. That pin mapping will only
321  * contain a single group of pins, and that group of pins will only have a
322  * single function that can be selected.
323  */
324 static int rza2_dt_node_to_map(struct pinctrl_dev *pctldev,
325 			       struct device_node *np,
326 			       struct pinctrl_map **map,
327 			       unsigned int *num_maps)
328 {
329 	struct rza2_pinctrl_priv *priv = pinctrl_dev_get_drvdata(pctldev);
330 	unsigned int *pins, *psel_val;
331 	int i, ret, npins, gsel, fsel;
332 	struct property *of_pins;
333 	const char **pin_fn;
334 
335 	/* Find out how many pins to map */
336 	of_pins = of_find_property(np, "pinmux", NULL);
337 	if (!of_pins) {
338 		dev_info(priv->dev, "Missing pinmux property\n");
339 		return -ENOENT;
340 	}
341 	npins = of_pins->length / sizeof(u32);
342 
343 	pins = devm_kcalloc(priv->dev, npins, sizeof(*pins), GFP_KERNEL);
344 	psel_val = devm_kcalloc(priv->dev, npins, sizeof(*psel_val),
345 				GFP_KERNEL);
346 	pin_fn = devm_kzalloc(priv->dev, sizeof(*pin_fn), GFP_KERNEL);
347 	if (!pins || !psel_val || !pin_fn)
348 		return -ENOMEM;
349 
350 	/* Collect pin locations and mux settings from DT properties */
351 	for (i = 0; i < npins; ++i) {
352 		u32 value;
353 
354 		ret = of_property_read_u32_index(np, "pinmux", i, &value);
355 		if (ret)
356 			return ret;
357 		pins[i] = value & MUX_PIN_ID_MASK;
358 		psel_val[i] = MUX_FUNC(value);
359 	}
360 
361 	/* Register a single pin group listing all the pins we read from DT */
362 	gsel = pinctrl_generic_add_group(pctldev, np->name, pins, npins, NULL);
363 	if (gsel < 0)
364 		return gsel;
365 
366 	/*
367 	 * Register a single group function where the 'data' is an array PSEL
368 	 * register values read from DT.
369 	 */
370 	pin_fn[0] = np->name;
371 	fsel = pinmux_generic_add_function(pctldev, np->name, pin_fn, 1,
372 					   psel_val);
373 	if (fsel < 0) {
374 		ret = fsel;
375 		goto remove_group;
376 	}
377 
378 	dev_dbg(priv->dev, "Parsed %pOF with %d pins\n", np, npins);
379 
380 	/* Create map where to retrieve function and mux settings from */
381 	*num_maps = 0;
382 	*map = kzalloc(sizeof(**map), GFP_KERNEL);
383 	if (!*map) {
384 		ret = -ENOMEM;
385 		goto remove_function;
386 	}
387 
388 	(*map)->type = PIN_MAP_TYPE_MUX_GROUP;
389 	(*map)->data.mux.group = np->name;
390 	(*map)->data.mux.function = np->name;
391 	*num_maps = 1;
392 
393 	return 0;
394 
395 remove_function:
396 	pinmux_generic_remove_function(pctldev, fsel);
397 
398 remove_group:
399 	pinctrl_generic_remove_group(pctldev, gsel);
400 
401 	dev_err(priv->dev, "Unable to parse DT node %s\n", np->name);
402 
403 	return ret;
404 }
405 
406 static void rza2_dt_free_map(struct pinctrl_dev *pctldev,
407 			     struct pinctrl_map *map, unsigned int num_maps)
408 {
409 	kfree(map);
410 }
411 
412 static const struct pinctrl_ops rza2_pinctrl_ops = {
413 	.get_groups_count	= pinctrl_generic_get_group_count,
414 	.get_group_name		= pinctrl_generic_get_group_name,
415 	.get_group_pins		= pinctrl_generic_get_group_pins,
416 	.dt_node_to_map		= rza2_dt_node_to_map,
417 	.dt_free_map		= rza2_dt_free_map,
418 };
419 
420 static int rza2_set_mux(struct pinctrl_dev *pctldev, unsigned int selector,
421 			unsigned int group)
422 {
423 	struct rza2_pinctrl_priv *priv = pinctrl_dev_get_drvdata(pctldev);
424 	struct function_desc *func;
425 	unsigned int i, *psel_val;
426 	struct group_desc *grp;
427 
428 	grp = pinctrl_generic_get_group(pctldev, group);
429 	if (!grp)
430 		return -EINVAL;
431 
432 	func = pinmux_generic_get_function(pctldev, selector);
433 	if (!func)
434 		return -EINVAL;
435 
436 	psel_val = func->data;
437 
438 	for (i = 0; i < grp->num_pins; ++i) {
439 		dev_dbg(priv->dev, "Setting P%c_%d to PSEL=%d\n",
440 			port_names[RZA2_PIN_ID_TO_PORT(grp->pins[i])],
441 			RZA2_PIN_ID_TO_PIN(grp->pins[i]),
442 			psel_val[i]);
443 		rza2_set_pin_function(
444 			priv->base,
445 			RZA2_PIN_ID_TO_PORT(grp->pins[i]),
446 			RZA2_PIN_ID_TO_PIN(grp->pins[i]),
447 			psel_val[i]);
448 	}
449 
450 	return 0;
451 }
452 
453 static const struct pinmux_ops rza2_pinmux_ops = {
454 	.get_functions_count	= pinmux_generic_get_function_count,
455 	.get_function_name	= pinmux_generic_get_function_name,
456 	.get_function_groups	= pinmux_generic_get_function_groups,
457 	.set_mux		= rza2_set_mux,
458 	.strict			= true,
459 };
460 
461 static int rza2_pinctrl_probe(struct platform_device *pdev)
462 {
463 	struct rza2_pinctrl_priv *priv;
464 	int ret;
465 
466 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
467 	if (!priv)
468 		return -ENOMEM;
469 
470 	priv->dev = &pdev->dev;
471 
472 	priv->base = devm_platform_ioremap_resource(pdev, 0);
473 	if (IS_ERR(priv->base))
474 		return PTR_ERR(priv->base);
475 
476 	platform_set_drvdata(pdev, priv);
477 
478 	priv->npins = (int)(uintptr_t)of_device_get_match_data(&pdev->dev) *
479 		      RZA2_PINS_PER_PORT;
480 
481 	priv->desc.name		= DRIVER_NAME;
482 	priv->desc.pctlops	= &rza2_pinctrl_ops;
483 	priv->desc.pmxops	= &rza2_pinmux_ops;
484 	priv->desc.owner	= THIS_MODULE;
485 
486 	ret = rza2_pinctrl_register(priv);
487 	if (ret)
488 		return ret;
489 
490 	dev_info(&pdev->dev, "Registered ports P0 - P%c\n",
491 		 port_names[priv->desc.npins / RZA2_PINS_PER_PORT - 1]);
492 
493 	return 0;
494 }
495 
496 static const struct of_device_id rza2_pinctrl_of_match[] = {
497 	{ .compatible = "renesas,r7s9210-pinctrl", .data = (void *)22, },
498 	{ /* sentinel */ }
499 };
500 
501 static struct platform_driver rza2_pinctrl_driver = {
502 	.driver = {
503 		.name = DRIVER_NAME,
504 		.of_match_table = rza2_pinctrl_of_match,
505 	},
506 	.probe = rza2_pinctrl_probe,
507 };
508 
509 static int __init rza2_pinctrl_init(void)
510 {
511 	return platform_driver_register(&rza2_pinctrl_driver);
512 }
513 core_initcall(rza2_pinctrl_init);
514 
515 MODULE_AUTHOR("Chris Brandt <chris.brandt@renesas.com>");
516 MODULE_DESCRIPTION("Pin and gpio controller driver for RZ/A2 SoC");
517 MODULE_LICENSE("GPL v2");
518