xref: /openbmc/linux/arch/mips/ar7/gpio.c (revision 8e9356c6)
1 /*
2  * Copyright (C) 2007 Felix Fietkau <nbd@openwrt.org>
3  * Copyright (C) 2007 Eugene Konev <ejka@openwrt.org>
4  * Copyright (C) 2009-2010 Florian Fainelli <florian@openwrt.org>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
19  */
20 
21 #include <linux/module.h>
22 #include <linux/gpio.h>
23 
24 #include <asm/mach-ar7/gpio.h>
25 
26 struct ar7_gpio_chip {
27 	void __iomem		*regs;
28 	struct gpio_chip	chip;
29 };
30 
31 static int ar7_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
32 {
33 	struct ar7_gpio_chip *gpch =
34 				container_of(chip, struct ar7_gpio_chip, chip);
35 	void __iomem *gpio_in = gpch->regs + AR7_GPIO_INPUT;
36 
37 	return readl(gpio_in) & (1 << gpio);
38 }
39 
40 static int titan_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
41 {
42 	struct ar7_gpio_chip *gpch =
43 				container_of(chip, struct ar7_gpio_chip, chip);
44 	void __iomem *gpio_in0 = gpch->regs + TITAN_GPIO_INPUT_0;
45 	void __iomem *gpio_in1 = gpch->regs + TITAN_GPIO_INPUT_1;
46 
47 	return readl(gpio >> 5 ? gpio_in1 : gpio_in0) & (1 << (gpio & 0x1f));
48 }
49 
50 static void ar7_gpio_set_value(struct gpio_chip *chip,
51 				unsigned gpio, int value)
52 {
53 	struct ar7_gpio_chip *gpch =
54 				container_of(chip, struct ar7_gpio_chip, chip);
55 	void __iomem *gpio_out = gpch->regs + AR7_GPIO_OUTPUT;
56 	unsigned tmp;
57 
58 	tmp = readl(gpio_out) & ~(1 << gpio);
59 	if (value)
60 		tmp |= 1 << gpio;
61 	writel(tmp, gpio_out);
62 }
63 
64 static void titan_gpio_set_value(struct gpio_chip *chip,
65 				unsigned gpio, int value)
66 {
67 	struct ar7_gpio_chip *gpch =
68 				container_of(chip, struct ar7_gpio_chip, chip);
69 	void __iomem *gpio_out0 = gpch->regs + TITAN_GPIO_OUTPUT_0;
70 	void __iomem *gpio_out1 = gpch->regs + TITAN_GPIO_OUTPUT_1;
71 	unsigned tmp;
72 
73 	tmp = readl(gpio >> 5 ? gpio_out1 : gpio_out0) & ~(1 << (gpio & 0x1f));
74 	if (value)
75 		tmp |= 1 << (gpio & 0x1f);
76 	writel(tmp, gpio >> 5 ? gpio_out1 : gpio_out0);
77 }
78 
79 static int ar7_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
80 {
81 	struct ar7_gpio_chip *gpch =
82 				container_of(chip, struct ar7_gpio_chip, chip);
83 	void __iomem *gpio_dir = gpch->regs + AR7_GPIO_DIR;
84 
85 	writel(readl(gpio_dir) | (1 << gpio), gpio_dir);
86 
87 	return 0;
88 }
89 
90 static int titan_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
91 {
92 	struct ar7_gpio_chip *gpch =
93 				container_of(chip, struct ar7_gpio_chip, chip);
94 	void __iomem *gpio_dir0 = gpch->regs + TITAN_GPIO_DIR_0;
95 	void __iomem *gpio_dir1 = gpch->regs + TITAN_GPIO_DIR_1;
96 
97 	if (gpio >= TITAN_GPIO_MAX)
98 		return -EINVAL;
99 
100 	writel(readl(gpio >> 5 ? gpio_dir1 : gpio_dir0) | (1 << (gpio & 0x1f)),
101 			gpio >> 5 ? gpio_dir1 : gpio_dir0);
102 	return 0;
103 }
104 
105 static int ar7_gpio_direction_output(struct gpio_chip *chip,
106 					unsigned gpio, int value)
107 {
108 	struct ar7_gpio_chip *gpch =
109 				container_of(chip, struct ar7_gpio_chip, chip);
110 	void __iomem *gpio_dir = gpch->regs + AR7_GPIO_DIR;
111 
112 	ar7_gpio_set_value(chip, gpio, value);
113 	writel(readl(gpio_dir) & ~(1 << gpio), gpio_dir);
114 
115 	return 0;
116 }
117 
118 static int titan_gpio_direction_output(struct gpio_chip *chip,
119 					unsigned gpio, int value)
120 {
121 	struct ar7_gpio_chip *gpch =
122 				container_of(chip, struct ar7_gpio_chip, chip);
123 	void __iomem *gpio_dir0 = gpch->regs + TITAN_GPIO_DIR_0;
124 	void __iomem *gpio_dir1 = gpch->regs + TITAN_GPIO_DIR_1;
125 
126 	if (gpio >= TITAN_GPIO_MAX)
127 		return -EINVAL;
128 
129 	titan_gpio_set_value(chip, gpio, value);
130 	writel(readl(gpio >> 5 ? gpio_dir1 : gpio_dir0) & ~(1 <<
131 		(gpio & 0x1f)), gpio >> 5 ? gpio_dir1 : gpio_dir0);
132 
133 	return 0;
134 }
135 
136 static struct ar7_gpio_chip ar7_gpio_chip = {
137 	.chip = {
138 		.label			= "ar7-gpio",
139 		.direction_input	= ar7_gpio_direction_input,
140 		.direction_output	= ar7_gpio_direction_output,
141 		.set			= ar7_gpio_set_value,
142 		.get			= ar7_gpio_get_value,
143 		.base			= 0,
144 		.ngpio			= AR7_GPIO_MAX,
145 	}
146 };
147 
148 static struct ar7_gpio_chip titan_gpio_chip = {
149 	.chip = {
150 		.label			= "titan-gpio",
151 		.direction_input	= titan_gpio_direction_input,
152 		.direction_output	= titan_gpio_direction_output,
153 		.set			= titan_gpio_set_value,
154 		.get			= titan_gpio_get_value,
155 		.base			= 0,
156 		.ngpio			= TITAN_GPIO_MAX,
157 	}
158 };
159 
160 static inline int ar7_gpio_enable_ar7(unsigned gpio)
161 {
162 	void __iomem *gpio_en = ar7_gpio_chip.regs + AR7_GPIO_ENABLE;
163 
164 	writel(readl(gpio_en) | (1 << gpio), gpio_en);
165 
166 	return 0;
167 }
168 
169 static inline int ar7_gpio_enable_titan(unsigned gpio)
170 {
171 	void __iomem *gpio_en0 = titan_gpio_chip.regs  + TITAN_GPIO_ENBL_0;
172 	void __iomem *gpio_en1 = titan_gpio_chip.regs  + TITAN_GPIO_ENBL_1;
173 
174 	writel(readl(gpio >> 5 ? gpio_en1 : gpio_en0) | (1 << (gpio & 0x1f)),
175 		gpio >> 5 ? gpio_en1 : gpio_en0);
176 
177 	return 0;
178 }
179 
180 int ar7_gpio_enable(unsigned gpio)
181 {
182 	return ar7_is_titan() ? ar7_gpio_enable_titan(gpio) :
183 				ar7_gpio_enable_ar7(gpio);
184 }
185 EXPORT_SYMBOL(ar7_gpio_enable);
186 
187 static inline int ar7_gpio_disable_ar7(unsigned gpio)
188 {
189 	void __iomem *gpio_en = ar7_gpio_chip.regs + AR7_GPIO_ENABLE;
190 
191 	writel(readl(gpio_en) & ~(1 << gpio), gpio_en);
192 
193 	return 0;
194 }
195 
196 static inline int ar7_gpio_disable_titan(unsigned gpio)
197 {
198 	void __iomem *gpio_en0 = titan_gpio_chip.regs + TITAN_GPIO_ENBL_0;
199 	void __iomem *gpio_en1 = titan_gpio_chip.regs + TITAN_GPIO_ENBL_1;
200 
201 	writel(readl(gpio >> 5 ? gpio_en1 : gpio_en0) & ~(1 << (gpio & 0x1f)),
202 			gpio >> 5 ? gpio_en1 : gpio_en0);
203 
204 	return 0;
205 }
206 
207 int ar7_gpio_disable(unsigned gpio)
208 {
209 	return ar7_is_titan() ? ar7_gpio_disable_titan(gpio) :
210 				ar7_gpio_disable_ar7(gpio);
211 }
212 EXPORT_SYMBOL(ar7_gpio_disable);
213 
214 struct titan_gpio_cfg {
215 	u32 reg;
216 	u32 shift;
217 	u32 func;
218 };
219 
220 static const struct titan_gpio_cfg titan_gpio_table[] = {
221 	/* reg, start bit, mux value */
222 	{4, 24, 1},
223 	{4, 26, 1},
224 	{4, 28, 1},
225 	{4, 30, 1},
226 	{5, 6, 1},
227 	{5, 8, 1},
228 	{5, 10, 1},
229 	{5, 12, 1},
230 	{7, 14, 3},
231 	{7, 16, 3},
232 	{7, 18, 3},
233 	{7, 20, 3},
234 	{7, 22, 3},
235 	{7, 26, 3},
236 	{7, 28, 3},
237 	{7, 30, 3},
238 	{8, 0, 3},
239 	{8, 2, 3},
240 	{8, 4, 3},
241 	{8, 10, 3},
242 	{8, 14, 3},
243 	{8, 16, 3},
244 	{8, 18, 3},
245 	{8, 20, 3},
246 	{9, 8, 3},
247 	{9, 10, 3},
248 	{9, 12, 3},
249 	{9, 14, 3},
250 	{9, 18, 3},
251 	{9, 20, 3},
252 	{9, 24, 3},
253 	{9, 26, 3},
254 	{9, 28, 3},
255 	{9, 30, 3},
256 	{10, 0, 3},
257 	{10, 2, 3},
258 	{10, 8, 3},
259 	{10, 10, 3},
260 	{10, 12, 3},
261 	{10, 14, 3},
262 	{13, 12, 3},
263 	{13, 14, 3},
264 	{13, 16, 3},
265 	{13, 18, 3},
266 	{13, 24, 3},
267 	{13, 26, 3},
268 	{13, 28, 3},
269 	{13, 30, 3},
270 	{14, 2, 3},
271 	{14, 6, 3},
272 	{14, 8, 3},
273 	{14, 12, 3}
274 };
275 
276 static int titan_gpio_pinsel(unsigned gpio)
277 {
278 	struct titan_gpio_cfg gpio_cfg;
279 	u32 mux_status, pin_sel_reg, tmp;
280 	void __iomem *pin_sel = (void __iomem *)KSEG1ADDR(AR7_REGS_PINSEL);
281 
282 	if (gpio >= ARRAY_SIZE(titan_gpio_table))
283 		return -EINVAL;
284 
285 	gpio_cfg = titan_gpio_table[gpio];
286 	pin_sel_reg = gpio_cfg.reg - 1;
287 
288 	mux_status = (readl(pin_sel + pin_sel_reg) >> gpio_cfg.shift) & 0x3;
289 
290 	/* Check the mux status */
291 	if (!((mux_status == 0) || (mux_status == gpio_cfg.func)))
292 		return 0;
293 
294 	/* Set the pin sel value */
295 	tmp = readl(pin_sel + pin_sel_reg);
296 	tmp |= ((gpio_cfg.func & 0x3) << gpio_cfg.shift);
297 	writel(tmp, pin_sel + pin_sel_reg);
298 
299 	return 0;
300 }
301 
302 /* Perform minimal Titan GPIO configuration */
303 static void titan_gpio_init(void)
304 {
305 	unsigned i;
306 
307 	for (i = 44; i < 48; i++) {
308 		titan_gpio_pinsel(i);
309 		ar7_gpio_enable_titan(i);
310 		titan_gpio_direction_input(&titan_gpio_chip.chip, i);
311 	}
312 }
313 
314 int __init ar7_gpio_init(void)
315 {
316 	int ret;
317 	struct ar7_gpio_chip *gpch;
318 	unsigned size;
319 
320 	if (!ar7_is_titan()) {
321 		gpch = &ar7_gpio_chip;
322 		size = 0x10;
323 	} else {
324 		gpch = &titan_gpio_chip;
325 		size = 0x1f;
326 	}
327 
328 	gpch->regs = ioremap_nocache(AR7_REGS_GPIO, size);
329 	if (!gpch->regs) {
330 		printk(KERN_ERR "%s: failed to ioremap regs\n",
331 					gpch->chip.label);
332 		return -ENOMEM;
333 	}
334 
335 	ret = gpiochip_add(&gpch->chip);
336 	if (ret) {
337 		printk(KERN_ERR "%s: failed to add gpiochip\n",
338 					gpch->chip.label);
339 		return ret;
340 	}
341 	printk(KERN_INFO "%s: registered %d GPIOs\n",
342 				gpch->chip.label, gpch->chip.ngpio);
343 
344 	if (ar7_is_titan())
345 		titan_gpio_init();
346 
347 	return ret;
348 }
349