xref: /linux/drivers/gpio/gpio-crystalcove.c (revision a2cce7a9f1b8cc3d4edce106fb971529f1d4d9ce) 
1 /*
2  * gpio-crystalcove.c - Intel Crystal Cove GPIO Driver
3  *
4  * Copyright (C) 2012, 2014 Intel Corporation. All rights reserved.
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License version
8  * 2 as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * Author: Yang, Bin <bin.yang@intel.com>
16  */
17 
18 #include <linux/interrupt.h>
19 #include <linux/module.h>
20 #include <linux/platform_device.h>
21 #include <linux/gpio.h>
22 #include <linux/seq_file.h>
23 #include <linux/bitops.h>
24 #include <linux/regmap.h>
25 #include <linux/mfd/intel_soc_pmic.h>
26 
27 #define CRYSTALCOVE_GPIO_NUM	16
28 #define CRYSTALCOVE_VGPIO_NUM	95
29 
30 #define UPDATE_IRQ_TYPE		BIT(0)
31 #define UPDATE_IRQ_MASK		BIT(1)
32 
33 #define GPIO0IRQ		0x0b
34 #define GPIO1IRQ		0x0c
35 #define MGPIO0IRQS0		0x19
36 #define MGPIO1IRQS0		0x1a
37 #define MGPIO0IRQSX		0x1b
38 #define MGPIO1IRQSX		0x1c
39 #define GPIO0P0CTLO		0x2b
40 #define GPIO0P0CTLI		0x33
41 #define GPIO1P0CTLO		0x3b
42 #define GPIO1P0CTLI		0x43
43 #define GPIOPANELCTL		0x52
44 
45 #define CTLI_INTCNT_DIS		(0)
46 #define CTLI_INTCNT_NE		(1 << 1)
47 #define CTLI_INTCNT_PE		(2 << 1)
48 #define CTLI_INTCNT_BE		(3 << 1)
49 
50 #define CTLO_DIR_IN		(0)
51 #define CTLO_DIR_OUT		(1 << 5)
52 
53 #define CTLO_DRV_CMOS		(0)
54 #define CTLO_DRV_OD		(1 << 4)
55 
56 #define CTLO_DRV_REN		(1 << 3)
57 
58 #define CTLO_RVAL_2KDW		(0)
59 #define CTLO_RVAL_2KUP		(1 << 1)
60 #define CTLO_RVAL_50KDW		(2 << 1)
61 #define CTLO_RVAL_50KUP		(3 << 1)
62 
63 #define CTLO_INPUT_SET	(CTLO_DRV_CMOS | CTLO_DRV_REN | CTLO_RVAL_2KUP)
64 #define CTLO_OUTPUT_SET	(CTLO_DIR_OUT | CTLO_INPUT_SET)
65 
66 enum ctrl_register {
67 	CTRL_IN,
68 	CTRL_OUT,
69 };
70 
71 /**
72  * struct crystalcove_gpio - Crystal Cove GPIO controller
73  * @buslock: for bus lock/sync and unlock.
74  * @chip: the abstract gpio_chip structure.
75  * @regmap: the regmap from the parent device.
76  * @update: pending IRQ setting update, to be written to the chip upon unlock.
77  * @intcnt_value: the Interrupt Detect value to be written.
78  * @set_irq_mask: true if the IRQ mask needs to be set, false to clear.
79  */
80 struct crystalcove_gpio {
81 	struct mutex buslock; /* irq_bus_lock */
82 	struct gpio_chip chip;
83 	struct regmap *regmap;
84 	int update;
85 	int intcnt_value;
86 	bool set_irq_mask;
87 };
88 
89 static inline struct crystalcove_gpio *to_cg(struct gpio_chip *gc)
90 {
91 	return container_of(gc, struct crystalcove_gpio, chip);
92 }
93 
94 static inline int to_reg(int gpio, enum ctrl_register reg_type)
95 {
96 	int reg;
97 
98 	if (gpio == 94)
99 		return GPIOPANELCTL;
100 
101 	if (reg_type == CTRL_IN) {
102 		if (gpio < 8)
103 			reg = GPIO0P0CTLI;
104 		else
105 			reg = GPIO1P0CTLI;
106 	} else {
107 		if (gpio < 8)
108 			reg = GPIO0P0CTLO;
109 		else
110 			reg = GPIO1P0CTLO;
111 	}
112 
113 	return reg + gpio % 8;
114 }
115 
116 static void crystalcove_update_irq_mask(struct crystalcove_gpio *cg,
117 					int gpio)
118 {
119 	u8 mirqs0 = gpio < 8 ? MGPIO0IRQS0 : MGPIO1IRQS0;
120 	int mask = BIT(gpio % 8);
121 
122 	if (cg->set_irq_mask)
123 		regmap_update_bits(cg->regmap, mirqs0, mask, mask);
124 	else
125 		regmap_update_bits(cg->regmap, mirqs0, mask, 0);
126 }
127 
128 static void crystalcove_update_irq_ctrl(struct crystalcove_gpio *cg, int gpio)
129 {
130 	int reg = to_reg(gpio, CTRL_IN);
131 
132 	regmap_update_bits(cg->regmap, reg, CTLI_INTCNT_BE, cg->intcnt_value);
133 }
134 
135 static int crystalcove_gpio_dir_in(struct gpio_chip *chip, unsigned gpio)
136 {
137 	struct crystalcove_gpio *cg = to_cg(chip);
138 
139 	if (gpio > CRYSTALCOVE_VGPIO_NUM)
140 		return 0;
141 
142 	return regmap_write(cg->regmap, to_reg(gpio, CTRL_OUT),
143 			    CTLO_INPUT_SET);
144 }
145 
146 static int crystalcove_gpio_dir_out(struct gpio_chip *chip, unsigned gpio,
147 				    int value)
148 {
149 	struct crystalcove_gpio *cg = to_cg(chip);
150 
151 	if (gpio > CRYSTALCOVE_VGPIO_NUM)
152 		return 0;
153 
154 	return regmap_write(cg->regmap, to_reg(gpio, CTRL_OUT),
155 			    CTLO_OUTPUT_SET | value);
156 }
157 
158 static int crystalcove_gpio_get(struct gpio_chip *chip, unsigned gpio)
159 {
160 	struct crystalcove_gpio *cg = to_cg(chip);
161 	int ret;
162 	unsigned int val;
163 
164 	if (gpio > CRYSTALCOVE_VGPIO_NUM)
165 		return 0;
166 
167 	ret = regmap_read(cg->regmap, to_reg(gpio, CTRL_IN), &val);
168 	if (ret)
169 		return ret;
170 
171 	return val & 0x1;
172 }
173 
174 static void crystalcove_gpio_set(struct gpio_chip *chip,
175 				 unsigned gpio, int value)
176 {
177 	struct crystalcove_gpio *cg = to_cg(chip);
178 
179 	if (gpio > CRYSTALCOVE_VGPIO_NUM)
180 		return;
181 
182 	if (value)
183 		regmap_update_bits(cg->regmap, to_reg(gpio, CTRL_OUT), 1, 1);
184 	else
185 		regmap_update_bits(cg->regmap, to_reg(gpio, CTRL_OUT), 1, 0);
186 }
187 
188 static int crystalcove_irq_type(struct irq_data *data, unsigned type)
189 {
190 	struct crystalcove_gpio *cg = to_cg(irq_data_get_irq_chip_data(data));
191 
192 	switch (type) {
193 	case IRQ_TYPE_NONE:
194 		cg->intcnt_value = CTLI_INTCNT_DIS;
195 		break;
196 	case IRQ_TYPE_EDGE_BOTH:
197 		cg->intcnt_value = CTLI_INTCNT_BE;
198 		break;
199 	case IRQ_TYPE_EDGE_RISING:
200 		cg->intcnt_value = CTLI_INTCNT_PE;
201 		break;
202 	case IRQ_TYPE_EDGE_FALLING:
203 		cg->intcnt_value = CTLI_INTCNT_NE;
204 		break;
205 	default:
206 		return -EINVAL;
207 	}
208 
209 	cg->update |= UPDATE_IRQ_TYPE;
210 
211 	return 0;
212 }
213 
214 static void crystalcove_bus_lock(struct irq_data *data)
215 {
216 	struct crystalcove_gpio *cg = to_cg(irq_data_get_irq_chip_data(data));
217 
218 	mutex_lock(&cg->buslock);
219 }
220 
221 static void crystalcove_bus_sync_unlock(struct irq_data *data)
222 {
223 	struct crystalcove_gpio *cg = to_cg(irq_data_get_irq_chip_data(data));
224 	int gpio = data->hwirq;
225 
226 	if (cg->update & UPDATE_IRQ_TYPE)
227 		crystalcove_update_irq_ctrl(cg, gpio);
228 	if (cg->update & UPDATE_IRQ_MASK)
229 		crystalcove_update_irq_mask(cg, gpio);
230 	cg->update = 0;
231 
232 	mutex_unlock(&cg->buslock);
233 }
234 
235 static void crystalcove_irq_unmask(struct irq_data *data)
236 {
237 	struct crystalcove_gpio *cg = to_cg(irq_data_get_irq_chip_data(data));
238 
239 	cg->set_irq_mask = false;
240 	cg->update |= UPDATE_IRQ_MASK;
241 }
242 
243 static void crystalcove_irq_mask(struct irq_data *data)
244 {
245 	struct crystalcove_gpio *cg = to_cg(irq_data_get_irq_chip_data(data));
246 
247 	cg->set_irq_mask = true;
248 	cg->update |= UPDATE_IRQ_MASK;
249 }
250 
251 static struct irq_chip crystalcove_irqchip = {
252 	.name			= "Crystal Cove",
253 	.irq_mask		= crystalcove_irq_mask,
254 	.irq_unmask		= crystalcove_irq_unmask,
255 	.irq_set_type		= crystalcove_irq_type,
256 	.irq_bus_lock		= crystalcove_bus_lock,
257 	.irq_bus_sync_unlock	= crystalcove_bus_sync_unlock,
258 	.flags			= IRQCHIP_SKIP_SET_WAKE,
259 };
260 
261 static irqreturn_t crystalcove_gpio_irq_handler(int irq, void *data)
262 {
263 	struct crystalcove_gpio *cg = data;
264 	unsigned int p0, p1;
265 	int pending;
266 	int gpio;
267 	unsigned int virq;
268 
269 	if (regmap_read(cg->regmap, GPIO0IRQ, &p0) ||
270 	    regmap_read(cg->regmap, GPIO1IRQ, &p1))
271 		return IRQ_NONE;
272 
273 	regmap_write(cg->regmap, GPIO0IRQ, p0);
274 	regmap_write(cg->regmap, GPIO1IRQ, p1);
275 
276 	pending = p0 | p1 << 8;
277 
278 	for (gpio = 0; gpio < CRYSTALCOVE_GPIO_NUM; gpio++) {
279 		if (pending & BIT(gpio)) {
280 			virq = irq_find_mapping(cg->chip.irqdomain, gpio);
281 			handle_nested_irq(virq);
282 		}
283 	}
284 
285 	return IRQ_HANDLED;
286 }
287 
288 static void crystalcove_gpio_dbg_show(struct seq_file *s,
289 				      struct gpio_chip *chip)
290 {
291 	struct crystalcove_gpio *cg = to_cg(chip);
292 	int gpio, offset;
293 	unsigned int ctlo, ctli, mirqs0, mirqsx, irq;
294 
295 	for (gpio = 0; gpio < CRYSTALCOVE_GPIO_NUM; gpio++) {
296 		regmap_read(cg->regmap, to_reg(gpio, CTRL_OUT), &ctlo);
297 		regmap_read(cg->regmap, to_reg(gpio, CTRL_IN), &ctli);
298 		regmap_read(cg->regmap, gpio < 8 ? MGPIO0IRQS0 : MGPIO1IRQS0,
299 			    &mirqs0);
300 		regmap_read(cg->regmap, gpio < 8 ? MGPIO0IRQSX : MGPIO1IRQSX,
301 			    &mirqsx);
302 		regmap_read(cg->regmap, gpio < 8 ? GPIO0IRQ : GPIO1IRQ,
303 			    &irq);
304 
305 		offset = gpio % 8;
306 		seq_printf(s, " gpio-%-2d %s %s %s %s ctlo=%2x,%s %s %s\n",
307 			   gpio, ctlo & CTLO_DIR_OUT ? "out" : "in ",
308 			   ctli & 0x1 ? "hi" : "lo",
309 			   ctli & CTLI_INTCNT_NE ? "fall" : "    ",
310 			   ctli & CTLI_INTCNT_PE ? "rise" : "    ",
311 			   ctlo,
312 			   mirqs0 & BIT(offset) ? "s0 mask  " : "s0 unmask",
313 			   mirqsx & BIT(offset) ? "sx mask  " : "sx unmask",
314 			   irq & BIT(offset) ? "pending" : "       ");
315 	}
316 }
317 
318 static int crystalcove_gpio_probe(struct platform_device *pdev)
319 {
320 	int irq = platform_get_irq(pdev, 0);
321 	struct crystalcove_gpio *cg;
322 	int retval;
323 	struct device *dev = pdev->dev.parent;
324 	struct intel_soc_pmic *pmic = dev_get_drvdata(dev);
325 
326 	if (irq < 0)
327 		return irq;
328 
329 	cg = devm_kzalloc(&pdev->dev, sizeof(*cg), GFP_KERNEL);
330 	if (!cg)
331 		return -ENOMEM;
332 
333 	platform_set_drvdata(pdev, cg);
334 
335 	mutex_init(&cg->buslock);
336 	cg->chip.label = KBUILD_MODNAME;
337 	cg->chip.direction_input = crystalcove_gpio_dir_in;
338 	cg->chip.direction_output = crystalcove_gpio_dir_out;
339 	cg->chip.get = crystalcove_gpio_get;
340 	cg->chip.set = crystalcove_gpio_set;
341 	cg->chip.base = -1;
342 	cg->chip.ngpio = CRYSTALCOVE_VGPIO_NUM;
343 	cg->chip.can_sleep = true;
344 	cg->chip.dev = dev;
345 	cg->chip.dbg_show = crystalcove_gpio_dbg_show;
346 	cg->regmap = pmic->regmap;
347 
348 	retval = gpiochip_add(&cg->chip);
349 	if (retval) {
350 		dev_warn(&pdev->dev, "add gpio chip error: %d\n", retval);
351 		return retval;
352 	}
353 
354 	gpiochip_irqchip_add(&cg->chip, &crystalcove_irqchip, 0,
355 			     handle_simple_irq, IRQ_TYPE_NONE);
356 
357 	retval = request_threaded_irq(irq, NULL, crystalcove_gpio_irq_handler,
358 				      IRQF_ONESHOT, KBUILD_MODNAME, cg);
359 
360 	if (retval) {
361 		dev_warn(&pdev->dev, "request irq failed: %d\n", retval);
362 		goto out_remove_gpio;
363 	}
364 
365 	return 0;
366 
367 out_remove_gpio:
368 	gpiochip_remove(&cg->chip);
369 	return retval;
370 }
371 
372 static int crystalcove_gpio_remove(struct platform_device *pdev)
373 {
374 	struct crystalcove_gpio *cg = platform_get_drvdata(pdev);
375 	int irq = platform_get_irq(pdev, 0);
376 
377 	gpiochip_remove(&cg->chip);
378 	if (irq >= 0)
379 		free_irq(irq, cg);
380 	return 0;
381 }
382 
383 static struct platform_driver crystalcove_gpio_driver = {
384 	.probe = crystalcove_gpio_probe,
385 	.remove = crystalcove_gpio_remove,
386 	.driver = {
387 		.name = "crystal_cove_gpio",
388 	},
389 };
390 
391 module_platform_driver(crystalcove_gpio_driver);
392 
393 MODULE_AUTHOR("Yang, Bin <bin.yang@intel.com>");
394 MODULE_DESCRIPTION("Intel Crystal Cove GPIO Driver");
395 MODULE_LICENSE("GPL v2");
396