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/mutex.h>
18 #include <linux/of.h>
19 #include <linux/pinctrl/consumer.h>
20 #include <linux/pinctrl/pinmux.h>
21 #include <linux/platform_device.h>
22 
23 #include "../core.h"
24 #include "../pinmux.h"
25 
26 #define DRIVER_NAME		"pinctrl-rza2"
27 
28 #define RZA2_PINS_PER_PORT	8
29 #define RZA2_PIN_ID_TO_PORT(id)	((id) / RZA2_PINS_PER_PORT)
30 #define RZA2_PIN_ID_TO_PIN(id)	((id) % RZA2_PINS_PER_PORT)
31 
32 /*
33  * Use 16 lower bits [15:0] for pin identifier
34  * Use 16 higher bits [31:16] for pin mux function
35  */
36 #define MUX_PIN_ID_MASK		GENMASK(15, 0)
37 #define MUX_FUNC_MASK		GENMASK(31, 16)
38 #define MUX_FUNC_OFFS		16
39 #define MUX_FUNC(pinconf)	((pinconf & MUX_FUNC_MASK) >> MUX_FUNC_OFFS)
40 
41 static const char port_names[] = "0123456789ABCDEFGHJKLM";
42 
43 struct rza2_pinctrl_priv {
44 	struct device *dev;
45 	void __iomem *base;
46 
47 	struct pinctrl_pin_desc *pins;
48 	struct pinctrl_desc desc;
49 	struct pinctrl_dev *pctl;
50 	struct pinctrl_gpio_range gpio_range;
51 	int npins;
52 	struct mutex mutex; /* serialize adding groups and functions */
53 };
54 
55 #define RZA2_PDR(port)		(0x0000 + (port) * 2)	/* Direction 16-bit */
56 #define RZA2_PODR(port)		(0x0040 + (port))	/* Output Data 8-bit */
57 #define RZA2_PIDR(port)		(0x0060 + (port))	/* Input Data 8-bit */
58 #define RZA2_PMR(port)		(0x0080 + (port))	/* Mode 8-bit */
59 #define RZA2_DSCR(port)		(0x0140 + (port) * 2)	/* Drive 16-bit */
60 #define RZA2_PFS(port, pin)	(0x0200 + ((port) * 8) + (pin))	/* Fnct 8-bit */
61 
62 #define RZA2_PWPR		0x02ff	/* Write Protect 8-bit */
63 #define RZA2_PFENET		0x0820	/* Ethernet Pins 8-bit */
64 #define RZA2_PPOC		0x0900	/* Dedicated Pins 32-bit */
65 #define RZA2_PHMOMO		0x0980	/* Peripheral Pins 32-bit */
66 #define RZA2_PCKIO		0x09d0	/* CKIO Drive 8-bit */
67 
68 #define RZA2_PDR_INPUT		0x02
69 #define RZA2_PDR_OUTPUT		0x03
70 #define RZA2_PDR_MASK		0x03
71 
72 #define PWPR_B0WI		BIT(7)	/* Bit Write Disable */
73 #define PWPR_PFSWE		BIT(6)	/* PFS Register Write Enable */
74 #define PFS_ISEL		BIT(6)	/* Interrupt Select */
75 
rza2_set_pin_function(void __iomem * pfc_base,u8 port,u8 pin,u8 func)76 static void rza2_set_pin_function(void __iomem *pfc_base, u8 port, u8 pin,
77 				  u8 func)
78 {
79 	u16 mask16;
80 	u16 reg16;
81 	u8 reg8;
82 
83 	/* Set pin to 'Non-use (Hi-z input protection)'  */
84 	reg16 = readw(pfc_base + RZA2_PDR(port));
85 	mask16 = RZA2_PDR_MASK << (pin * 2);
86 	reg16 &= ~mask16;
87 	writew(reg16, pfc_base + RZA2_PDR(port));
88 
89 	/* Temporarily switch to GPIO */
90 	reg8 = readb(pfc_base + RZA2_PMR(port));
91 	reg8 &= ~BIT(pin);
92 	writeb(reg8, pfc_base + RZA2_PMR(port));
93 
94 	/* PFS Register Write Protect : OFF */
95 	writeb(0x00, pfc_base + RZA2_PWPR);		/* B0WI=0, PFSWE=0 */
96 	writeb(PWPR_PFSWE, pfc_base + RZA2_PWPR);	/* B0WI=0, PFSWE=1 */
97 
98 	/* Set Pin function (interrupt disabled, ISEL=0) */
99 	writeb(func, pfc_base + RZA2_PFS(port, pin));
100 
101 	/* PFS Register Write Protect : ON */
102 	writeb(0x00, pfc_base + RZA2_PWPR);	/* B0WI=0, PFSWE=0 */
103 	writeb(0x80, pfc_base + RZA2_PWPR);	/* B0WI=1, PFSWE=0 */
104 
105 	/* Port Mode  : Peripheral module pin functions */
106 	reg8 = readb(pfc_base + RZA2_PMR(port));
107 	reg8 |= BIT(pin);
108 	writeb(reg8, pfc_base + RZA2_PMR(port));
109 }
110 
rza2_pin_to_gpio(void __iomem * pfc_base,unsigned int offset,u8 dir)111 static void rza2_pin_to_gpio(void __iomem *pfc_base, unsigned int offset,
112 			     u8 dir)
113 {
114 	u8 port = RZA2_PIN_ID_TO_PORT(offset);
115 	u8 pin = RZA2_PIN_ID_TO_PIN(offset);
116 	u16 mask16;
117 	u16 reg16;
118 
119 	reg16 = readw(pfc_base + RZA2_PDR(port));
120 	mask16 = RZA2_PDR_MASK << (pin * 2);
121 	reg16 &= ~mask16;
122 
123 	if (dir)
124 		reg16 |= RZA2_PDR_INPUT << (pin * 2);	/* pin as input */
125 	else
126 		reg16 |= RZA2_PDR_OUTPUT << (pin * 2);	/* pin as output */
127 
128 	writew(reg16, pfc_base + RZA2_PDR(port));
129 }
130 
rza2_chip_get_direction(struct gpio_chip * chip,unsigned int offset)131 static int rza2_chip_get_direction(struct gpio_chip *chip, unsigned int offset)
132 {
133 	struct rza2_pinctrl_priv *priv = gpiochip_get_data(chip);
134 	u8 port = RZA2_PIN_ID_TO_PORT(offset);
135 	u8 pin = RZA2_PIN_ID_TO_PIN(offset);
136 	u16 reg16;
137 
138 	reg16 = readw(priv->base + RZA2_PDR(port));
139 	reg16 = (reg16 >> (pin * 2)) & RZA2_PDR_MASK;
140 
141 	if (reg16 == RZA2_PDR_OUTPUT)
142 		return GPIO_LINE_DIRECTION_OUT;
143 
144 	if (reg16 == RZA2_PDR_INPUT)
145 		return GPIO_LINE_DIRECTION_IN;
146 
147 	/*
148 	 * This GPIO controller has a default Hi-Z state that is not input or
149 	 * output, so force the pin to input now.
150 	 */
151 	rza2_pin_to_gpio(priv->base, offset, 1);
152 
153 	return GPIO_LINE_DIRECTION_IN;
154 }
155 
rza2_chip_direction_input(struct gpio_chip * chip,unsigned int offset)156 static int rza2_chip_direction_input(struct gpio_chip *chip,
157 				     unsigned int offset)
158 {
159 	struct rza2_pinctrl_priv *priv = gpiochip_get_data(chip);
160 
161 	rza2_pin_to_gpio(priv->base, offset, 1);
162 
163 	return 0;
164 }
165 
rza2_chip_get(struct gpio_chip * chip,unsigned int offset)166 static int rza2_chip_get(struct gpio_chip *chip, unsigned int offset)
167 {
168 	struct rza2_pinctrl_priv *priv = gpiochip_get_data(chip);
169 	u8 port = RZA2_PIN_ID_TO_PORT(offset);
170 	u8 pin = RZA2_PIN_ID_TO_PIN(offset);
171 
172 	return !!(readb(priv->base + RZA2_PIDR(port)) & BIT(pin));
173 }
174 
rza2_chip_set(struct gpio_chip * chip,unsigned int offset,int value)175 static void rza2_chip_set(struct gpio_chip *chip, unsigned int offset,
176 			  int value)
177 {
178 	struct rza2_pinctrl_priv *priv = gpiochip_get_data(chip);
179 	u8 port = RZA2_PIN_ID_TO_PORT(offset);
180 	u8 pin = RZA2_PIN_ID_TO_PIN(offset);
181 	u8 new_value;
182 
183 	new_value = readb(priv->base + RZA2_PODR(port));
184 
185 	if (value)
186 		new_value |= BIT(pin);
187 	else
188 		new_value &= ~BIT(pin);
189 
190 	writeb(new_value, priv->base + RZA2_PODR(port));
191 }
192 
rza2_chip_direction_output(struct gpio_chip * chip,unsigned int offset,int val)193 static int rza2_chip_direction_output(struct gpio_chip *chip,
194 				      unsigned int offset, int val)
195 {
196 	struct rza2_pinctrl_priv *priv = gpiochip_get_data(chip);
197 
198 	rza2_chip_set(chip, offset, val);
199 	rza2_pin_to_gpio(priv->base, offset, 0);
200 
201 	return 0;
202 }
203 
204 static const char * const rza2_gpio_names[] = {
205 	"P0_0", "P0_1", "P0_2", "P0_3", "P0_4", "P0_5", "P0_6", "P0_7",
206 	"P1_0", "P1_1", "P1_2", "P1_3", "P1_4", "P1_5", "P1_6", "P1_7",
207 	"P2_0", "P2_1", "P2_2", "P2_3", "P2_4", "P2_5", "P2_6", "P2_7",
208 	"P3_0", "P3_1", "P3_2", "P3_3", "P3_4", "P3_5", "P3_6", "P3_7",
209 	"P4_0", "P4_1", "P4_2", "P4_3", "P4_4", "P4_5", "P4_6", "P4_7",
210 	"P5_0", "P5_1", "P5_2", "P5_3", "P5_4", "P5_5", "P5_6", "P5_7",
211 	"P6_0", "P6_1", "P6_2", "P6_3", "P6_4", "P6_5", "P6_6", "P6_7",
212 	"P7_0", "P7_1", "P7_2", "P7_3", "P7_4", "P7_5", "P7_6", "P7_7",
213 	"P8_0", "P8_1", "P8_2", "P8_3", "P8_4", "P8_5", "P8_6", "P8_7",
214 	"P9_0", "P9_1", "P9_2", "P9_3", "P9_4", "P9_5", "P9_6", "P9_7",
215 	"PA_0", "PA_1", "PA_2", "PA_3", "PA_4", "PA_5", "PA_6", "PA_7",
216 	"PB_0", "PB_1", "PB_2", "PB_3", "PB_4", "PB_5", "PB_6", "PB_7",
217 	"PC_0", "PC_1", "PC_2", "PC_3", "PC_4", "PC_5", "PC_6", "PC_7",
218 	"PD_0", "PD_1", "PD_2", "PD_3", "PD_4", "PD_5", "PD_6", "PD_7",
219 	"PE_0", "PE_1", "PE_2", "PE_3", "PE_4", "PE_5", "PE_6", "PE_7",
220 	"PF_0", "PF_1", "PF_2", "PF_3", "PF_4", "PF_5", "PF_6", "PF_7",
221 	"PG_0", "PG_1", "PG_2", "PG_3", "PG_4", "PG_5", "PG_6", "PG_7",
222 	"PH_0", "PH_1", "PH_2", "PH_3", "PH_4", "PH_5", "PH_6", "PH_7",
223 	/* port I does not exist */
224 	"PJ_0", "PJ_1", "PJ_2", "PJ_3", "PJ_4", "PJ_5", "PJ_6", "PJ_7",
225 	"PK_0", "PK_1", "PK_2", "PK_3", "PK_4", "PK_5", "PK_6", "PK_7",
226 	"PL_0", "PL_1", "PL_2", "PL_3", "PL_4", "PL_5", "PL_6", "PL_7",
227 	"PM_0", "PM_1", "PM_2", "PM_3", "PM_4", "PM_5", "PM_6", "PM_7",
228 };
229 
230 static struct gpio_chip chip = {
231 	.names = rza2_gpio_names,
232 	.base = -1,
233 	.request = pinctrl_gpio_request,
234 	.free = pinctrl_gpio_free,
235 	.get_direction = rza2_chip_get_direction,
236 	.direction_input = rza2_chip_direction_input,
237 	.direction_output = rza2_chip_direction_output,
238 	.get = rza2_chip_get,
239 	.set = rza2_chip_set,
240 };
241 
rza2_gpio_register(struct rza2_pinctrl_priv * priv)242 static int rza2_gpio_register(struct rza2_pinctrl_priv *priv)
243 {
244 	struct device_node *np = priv->dev->of_node;
245 	struct of_phandle_args of_args;
246 	int ret;
247 
248 	chip.label = devm_kasprintf(priv->dev, GFP_KERNEL, "%pOFn", np);
249 	chip.parent = priv->dev;
250 	chip.ngpio = priv->npins;
251 
252 	ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3, 0,
253 					       &of_args);
254 	if (ret) {
255 		dev_err(priv->dev, "Unable to parse gpio-ranges\n");
256 		return ret;
257 	}
258 
259 	of_node_put(of_args.np);
260 
261 	if ((of_args.args[0] != 0) ||
262 	    (of_args.args[1] != 0) ||
263 	    (of_args.args[2] != priv->npins)) {
264 		dev_err(priv->dev, "gpio-ranges does not match selected SOC\n");
265 		return -EINVAL;
266 	}
267 	priv->gpio_range.id = 0;
268 	priv->gpio_range.pin_base = priv->gpio_range.base = 0;
269 	priv->gpio_range.npins = priv->npins;
270 	priv->gpio_range.name = chip.label;
271 	priv->gpio_range.gc = &chip;
272 
273 	/* Register our gpio chip with gpiolib */
274 	ret = devm_gpiochip_add_data(priv->dev, &chip, priv);
275 	if (ret)
276 		return ret;
277 
278 	/* Register pin range with pinctrl core */
279 	pinctrl_add_gpio_range(priv->pctl, &priv->gpio_range);
280 
281 	dev_dbg(priv->dev, "Registered gpio controller\n");
282 
283 	return 0;
284 }
285 
rza2_pinctrl_register(struct rza2_pinctrl_priv * priv)286 static int rza2_pinctrl_register(struct rza2_pinctrl_priv *priv)
287 {
288 	struct pinctrl_pin_desc *pins;
289 	unsigned int i;
290 	int ret;
291 
292 	pins = devm_kcalloc(priv->dev, priv->npins, sizeof(*pins), GFP_KERNEL);
293 	if (!pins)
294 		return -ENOMEM;
295 
296 	priv->pins = pins;
297 	priv->desc.pins = pins;
298 	priv->desc.npins = priv->npins;
299 
300 	for (i = 0; i < priv->npins; i++) {
301 		pins[i].number = i;
302 		pins[i].name = rza2_gpio_names[i];
303 	}
304 
305 	ret = devm_pinctrl_register_and_init(priv->dev, &priv->desc, priv,
306 					     &priv->pctl);
307 	if (ret) {
308 		dev_err(priv->dev, "pinctrl registration failed\n");
309 		return ret;
310 	}
311 
312 	ret = pinctrl_enable(priv->pctl);
313 	if (ret) {
314 		dev_err(priv->dev, "pinctrl enable failed\n");
315 		return ret;
316 	}
317 
318 	ret = rza2_gpio_register(priv);
319 	if (ret) {
320 		dev_err(priv->dev, "GPIO registration failed\n");
321 		return ret;
322 	}
323 
324 	return 0;
325 }
326 
327 /*
328  * For each DT node, create a single pin mapping. That pin mapping will only
329  * contain a single group of pins, and that group of pins will only have a
330  * single function that can be selected.
331  */
rza2_dt_node_to_map(struct pinctrl_dev * pctldev,struct device_node * np,struct pinctrl_map ** map,unsigned int * num_maps)332 static int rza2_dt_node_to_map(struct pinctrl_dev *pctldev,
333 			       struct device_node *np,
334 			       struct pinctrl_map **map,
335 			       unsigned int *num_maps)
336 {
337 	struct rza2_pinctrl_priv *priv = pinctrl_dev_get_drvdata(pctldev);
338 	unsigned int *pins, *psel_val;
339 	int i, ret, npins, gsel, fsel;
340 	struct property *of_pins;
341 	const char **pin_fn;
342 
343 	/* Find out how many pins to map */
344 	of_pins = of_find_property(np, "pinmux", NULL);
345 	if (!of_pins) {
346 		dev_info(priv->dev, "Missing pinmux property\n");
347 		return -ENOENT;
348 	}
349 	npins = of_pins->length / sizeof(u32);
350 
351 	pins = devm_kcalloc(priv->dev, npins, sizeof(*pins), GFP_KERNEL);
352 	psel_val = devm_kcalloc(priv->dev, npins, sizeof(*psel_val),
353 				GFP_KERNEL);
354 	pin_fn = devm_kzalloc(priv->dev, sizeof(*pin_fn), GFP_KERNEL);
355 	if (!pins || !psel_val || !pin_fn)
356 		return -ENOMEM;
357 
358 	/* Collect pin locations and mux settings from DT properties */
359 	for (i = 0; i < npins; ++i) {
360 		u32 value;
361 
362 		ret = of_property_read_u32_index(np, "pinmux", i, &value);
363 		if (ret)
364 			return ret;
365 		pins[i] = value & MUX_PIN_ID_MASK;
366 		psel_val[i] = MUX_FUNC(value);
367 	}
368 
369 	mutex_lock(&priv->mutex);
370 
371 	/* Register a single pin group listing all the pins we read from DT */
372 	gsel = pinctrl_generic_add_group(pctldev, np->name, pins, npins, NULL);
373 	if (gsel < 0) {
374 		ret = gsel;
375 		goto unlock;
376 	}
377 
378 	/*
379 	 * Register a single group function where the 'data' is an array PSEL
380 	 * register values read from DT.
381 	 */
382 	pin_fn[0] = np->name;
383 	fsel = pinmux_generic_add_function(pctldev, np->name, pin_fn, 1,
384 					   psel_val);
385 	if (fsel < 0) {
386 		ret = fsel;
387 		goto remove_group;
388 	}
389 
390 	dev_dbg(priv->dev, "Parsed %pOF with %d pins\n", np, npins);
391 
392 	/* Create map where to retrieve function and mux settings from */
393 	*num_maps = 0;
394 	*map = kzalloc(sizeof(**map), GFP_KERNEL);
395 	if (!*map) {
396 		ret = -ENOMEM;
397 		goto remove_function;
398 	}
399 
400 	(*map)->type = PIN_MAP_TYPE_MUX_GROUP;
401 	(*map)->data.mux.group = np->name;
402 	(*map)->data.mux.function = np->name;
403 	*num_maps = 1;
404 
405 	mutex_unlock(&priv->mutex);
406 
407 	return 0;
408 
409 remove_function:
410 	pinmux_generic_remove_function(pctldev, fsel);
411 
412 remove_group:
413 	pinctrl_generic_remove_group(pctldev, gsel);
414 
415 unlock:
416 	mutex_unlock(&priv->mutex);
417 
418 	dev_err(priv->dev, "Unable to parse DT node %s\n", np->name);
419 
420 	return ret;
421 }
422 
rza2_dt_free_map(struct pinctrl_dev * pctldev,struct pinctrl_map * map,unsigned int num_maps)423 static void rza2_dt_free_map(struct pinctrl_dev *pctldev,
424 			     struct pinctrl_map *map, unsigned int num_maps)
425 {
426 	kfree(map);
427 }
428 
429 static const struct pinctrl_ops rza2_pinctrl_ops = {
430 	.get_groups_count	= pinctrl_generic_get_group_count,
431 	.get_group_name		= pinctrl_generic_get_group_name,
432 	.get_group_pins		= pinctrl_generic_get_group_pins,
433 	.dt_node_to_map		= rza2_dt_node_to_map,
434 	.dt_free_map		= rza2_dt_free_map,
435 };
436 
rza2_set_mux(struct pinctrl_dev * pctldev,unsigned int selector,unsigned int group)437 static int rza2_set_mux(struct pinctrl_dev *pctldev, unsigned int selector,
438 			unsigned int group)
439 {
440 	struct rza2_pinctrl_priv *priv = pinctrl_dev_get_drvdata(pctldev);
441 	struct function_desc *func;
442 	unsigned int i, *psel_val;
443 	struct group_desc *grp;
444 
445 	grp = pinctrl_generic_get_group(pctldev, group);
446 	if (!grp)
447 		return -EINVAL;
448 
449 	func = pinmux_generic_get_function(pctldev, selector);
450 	if (!func)
451 		return -EINVAL;
452 
453 	psel_val = func->data;
454 
455 	for (i = 0; i < grp->grp.npins; ++i) {
456 		dev_dbg(priv->dev, "Setting P%c_%d to PSEL=%d\n",
457 			port_names[RZA2_PIN_ID_TO_PORT(grp->grp.pins[i])],
458 			RZA2_PIN_ID_TO_PIN(grp->grp.pins[i]),
459 			psel_val[i]);
460 		rza2_set_pin_function(
461 			priv->base,
462 			RZA2_PIN_ID_TO_PORT(grp->grp.pins[i]),
463 			RZA2_PIN_ID_TO_PIN(grp->grp.pins[i]),
464 			psel_val[i]);
465 	}
466 
467 	return 0;
468 }
469 
470 static const struct pinmux_ops rza2_pinmux_ops = {
471 	.get_functions_count	= pinmux_generic_get_function_count,
472 	.get_function_name	= pinmux_generic_get_function_name,
473 	.get_function_groups	= pinmux_generic_get_function_groups,
474 	.set_mux		= rza2_set_mux,
475 	.strict			= true,
476 };
477 
rza2_pinctrl_probe(struct platform_device * pdev)478 static int rza2_pinctrl_probe(struct platform_device *pdev)
479 {
480 	struct rza2_pinctrl_priv *priv;
481 	int ret;
482 
483 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
484 	if (!priv)
485 		return -ENOMEM;
486 
487 	priv->dev = &pdev->dev;
488 
489 	priv->base = devm_platform_ioremap_resource(pdev, 0);
490 	if (IS_ERR(priv->base))
491 		return PTR_ERR(priv->base);
492 
493 	mutex_init(&priv->mutex);
494 
495 	platform_set_drvdata(pdev, priv);
496 
497 	priv->npins = (int)(uintptr_t)of_device_get_match_data(&pdev->dev) *
498 		      RZA2_PINS_PER_PORT;
499 
500 	priv->desc.name		= DRIVER_NAME;
501 	priv->desc.pctlops	= &rza2_pinctrl_ops;
502 	priv->desc.pmxops	= &rza2_pinmux_ops;
503 	priv->desc.owner	= THIS_MODULE;
504 
505 	ret = rza2_pinctrl_register(priv);
506 	if (ret)
507 		return ret;
508 
509 	dev_info(&pdev->dev, "Registered ports P0 - P%c\n",
510 		 port_names[priv->desc.npins / RZA2_PINS_PER_PORT - 1]);
511 
512 	return 0;
513 }
514 
515 static const struct of_device_id rza2_pinctrl_of_match[] = {
516 	{ .compatible = "renesas,r7s9210-pinctrl", .data = (void *)22, },
517 	{ /* sentinel */ }
518 };
519 
520 static struct platform_driver rza2_pinctrl_driver = {
521 	.driver = {
522 		.name = DRIVER_NAME,
523 		.of_match_table = rza2_pinctrl_of_match,
524 	},
525 	.probe = rza2_pinctrl_probe,
526 };
527 
rza2_pinctrl_init(void)528 static int __init rza2_pinctrl_init(void)
529 {
530 	return platform_driver_register(&rza2_pinctrl_driver);
531 }
532 core_initcall(rza2_pinctrl_init);
533 
534 MODULE_AUTHOR("Chris Brandt <[email protected]>");
535 MODULE_DESCRIPTION("Pin and gpio controller driver for RZ/A2 SoC");
536