xref: /openbmc/linux/drivers/gpio/gpio-sch.c (revision 24b1944f)
1 /*
2  * GPIO interface for Intel Poulsbo SCH
3  *
4  *  Copyright (c) 2010 CompuLab Ltd
5  *  Author: Denis Turischev <denis@compulab.co.il>
6  *
7  *  This program is free software; you can redistribute it and/or modify
8  *  it under the terms of the GNU General Public License 2 as published
9  *  by the Free Software Foundation.
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; see the file COPYING.  If not, write to
18  *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
19  */
20 
21 #include <linux/init.h>
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/io.h>
25 #include <linux/errno.h>
26 #include <linux/acpi.h>
27 #include <linux/platform_device.h>
28 #include <linux/pci_ids.h>
29 
30 #include <linux/gpio.h>
31 
32 static DEFINE_SPINLOCK(gpio_lock);
33 
34 #define CGEN	(0x00)
35 #define CGIO	(0x04)
36 #define CGLV	(0x08)
37 
38 #define RGEN	(0x20)
39 #define RGIO	(0x24)
40 #define RGLV	(0x28)
41 
42 static unsigned short gpio_ba;
43 
44 static int sch_gpio_core_direction_in(struct gpio_chip *gc, unsigned  gpio_num)
45 {
46 	u8 curr_dirs;
47 	unsigned short offset, bit;
48 
49 	spin_lock(&gpio_lock);
50 
51 	offset = CGIO + gpio_num / 8;
52 	bit = gpio_num % 8;
53 
54 	curr_dirs = inb(gpio_ba + offset);
55 
56 	if (!(curr_dirs & (1 << bit)))
57 		outb(curr_dirs | (1 << bit), gpio_ba + offset);
58 
59 	spin_unlock(&gpio_lock);
60 	return 0;
61 }
62 
63 static int sch_gpio_core_get(struct gpio_chip *gc, unsigned gpio_num)
64 {
65 	int res;
66 	unsigned short offset, bit;
67 
68 	offset = CGLV + gpio_num / 8;
69 	bit = gpio_num % 8;
70 
71 	res = !!(inb(gpio_ba + offset) & (1 << bit));
72 	return res;
73 }
74 
75 static void sch_gpio_core_set(struct gpio_chip *gc, unsigned gpio_num, int val)
76 {
77 	u8 curr_vals;
78 	unsigned short offset, bit;
79 
80 	spin_lock(&gpio_lock);
81 
82 	offset = CGLV + gpio_num / 8;
83 	bit = gpio_num % 8;
84 
85 	curr_vals = inb(gpio_ba + offset);
86 
87 	if (val)
88 		outb(curr_vals | (1 << bit), gpio_ba + offset);
89 	else
90 		outb((curr_vals & ~(1 << bit)), gpio_ba + offset);
91 	spin_unlock(&gpio_lock);
92 }
93 
94 static int sch_gpio_core_direction_out(struct gpio_chip *gc,
95 					unsigned gpio_num, int val)
96 {
97 	u8 curr_dirs;
98 	unsigned short offset, bit;
99 
100 	sch_gpio_core_set(gc, gpio_num, val);
101 
102 	spin_lock(&gpio_lock);
103 
104 	offset = CGIO + gpio_num / 8;
105 	bit = gpio_num % 8;
106 
107 	curr_dirs = inb(gpio_ba + offset);
108 	if (curr_dirs & (1 << bit))
109 		outb(curr_dirs & ~(1 << bit), gpio_ba + offset);
110 
111 	spin_unlock(&gpio_lock);
112 	return 0;
113 }
114 
115 static struct gpio_chip sch_gpio_core = {
116 	.label			= "sch_gpio_core",
117 	.owner			= THIS_MODULE,
118 	.direction_input	= sch_gpio_core_direction_in,
119 	.get			= sch_gpio_core_get,
120 	.direction_output	= sch_gpio_core_direction_out,
121 	.set			= sch_gpio_core_set,
122 };
123 
124 static int sch_gpio_resume_direction_in(struct gpio_chip *gc,
125 					unsigned gpio_num)
126 {
127 	u8 curr_dirs;
128 	unsigned short offset, bit;
129 
130 	spin_lock(&gpio_lock);
131 
132 	offset = RGIO + gpio_num / 8;
133 	bit = gpio_num % 8;
134 
135 	curr_dirs = inb(gpio_ba + offset);
136 
137 	if (!(curr_dirs & (1 << bit)))
138 		outb(curr_dirs | (1 << bit), gpio_ba + offset);
139 
140 	spin_unlock(&gpio_lock);
141 	return 0;
142 }
143 
144 static int sch_gpio_resume_get(struct gpio_chip *gc, unsigned gpio_num)
145 {
146 	unsigned short offset, bit;
147 
148 	offset = RGLV + gpio_num / 8;
149 	bit = gpio_num % 8;
150 
151 	return !!(inb(gpio_ba + offset) & (1 << bit));
152 }
153 
154 static void sch_gpio_resume_set(struct gpio_chip *gc,
155 				unsigned gpio_num, int val)
156 {
157 	u8 curr_vals;
158 	unsigned short offset, bit;
159 
160 	spin_lock(&gpio_lock);
161 
162 	offset = RGLV + gpio_num / 8;
163 	bit = gpio_num % 8;
164 
165 	curr_vals = inb(gpio_ba + offset);
166 
167 	if (val)
168 		outb(curr_vals | (1 << bit), gpio_ba + offset);
169 	else
170 		outb((curr_vals & ~(1 << bit)), gpio_ba + offset);
171 
172 	spin_unlock(&gpio_lock);
173 }
174 
175 static int sch_gpio_resume_direction_out(struct gpio_chip *gc,
176 					unsigned gpio_num, int val)
177 {
178 	u8 curr_dirs;
179 	unsigned short offset, bit;
180 
181 	sch_gpio_resume_set(gc, gpio_num, val);
182 
183 	offset = RGIO + gpio_num / 8;
184 	bit = gpio_num % 8;
185 
186 	spin_lock(&gpio_lock);
187 
188 	curr_dirs = inb(gpio_ba + offset);
189 	if (curr_dirs & (1 << bit))
190 		outb(curr_dirs & ~(1 << bit), gpio_ba + offset);
191 
192 	spin_unlock(&gpio_lock);
193 	return 0;
194 }
195 
196 static struct gpio_chip sch_gpio_resume = {
197 	.label			= "sch_gpio_resume",
198 	.owner			= THIS_MODULE,
199 	.direction_input	= sch_gpio_resume_direction_in,
200 	.get			= sch_gpio_resume_get,
201 	.direction_output	= sch_gpio_resume_direction_out,
202 	.set			= sch_gpio_resume_set,
203 };
204 
205 static int sch_gpio_probe(struct platform_device *pdev)
206 {
207 	struct resource *res;
208 	int err, id;
209 
210 	id = pdev->id;
211 	if (!id)
212 		return -ENODEV;
213 
214 	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
215 	if (!res)
216 		return -EBUSY;
217 
218 	if (!request_region(res->start, resource_size(res), pdev->name))
219 		return -EBUSY;
220 
221 	gpio_ba = res->start;
222 
223 	switch (id) {
224 	case PCI_DEVICE_ID_INTEL_SCH_LPC:
225 		sch_gpio_core.base = 0;
226 		sch_gpio_core.ngpio = 10;
227 		sch_gpio_resume.base = 10;
228 		sch_gpio_resume.ngpio = 4;
229 		/*
230 		 * GPIO[6:0] enabled by default
231 		 * GPIO7 is configured by the CMC as SLPIOVR
232 		 * Enable GPIO[9:8] core powered gpios explicitly
233 		 */
234 		outb(0x3, gpio_ba + CGEN + 1);
235 		/*
236 		 * SUS_GPIO[2:0] enabled by default
237 		 * Enable SUS_GPIO3 resume powered gpio explicitly
238 		 */
239 		outb(0x8, gpio_ba + RGEN);
240 		break;
241 
242 	case PCI_DEVICE_ID_INTEL_ITC_LPC:
243 		sch_gpio_core.base = 0;
244 		sch_gpio_core.ngpio = 5;
245 		sch_gpio_resume.base = 5;
246 		sch_gpio_resume.ngpio = 9;
247 		break;
248 
249 	case PCI_DEVICE_ID_INTEL_CENTERTON_ILB:
250 		sch_gpio_core.base = 0;
251 		sch_gpio_core.ngpio = 21;
252 		sch_gpio_resume.base = 21;
253 		sch_gpio_resume.ngpio = 9;
254 		break;
255 
256 	default:
257 		err = -ENODEV;
258 		goto err_sch_gpio_core;
259 	}
260 
261 	sch_gpio_core.dev = &pdev->dev;
262 	sch_gpio_resume.dev = &pdev->dev;
263 
264 	err = gpiochip_add(&sch_gpio_core);
265 	if (err < 0)
266 		goto err_sch_gpio_core;
267 
268 	err = gpiochip_add(&sch_gpio_resume);
269 	if (err < 0)
270 		goto err_sch_gpio_resume;
271 
272 	return 0;
273 
274 err_sch_gpio_resume:
275 	if (gpiochip_remove(&sch_gpio_core))
276 		dev_err(&pdev->dev, "%s gpiochip_remove failed\n", __func__);
277 
278 err_sch_gpio_core:
279 	release_region(res->start, resource_size(res));
280 	gpio_ba = 0;
281 
282 	return err;
283 }
284 
285 static int sch_gpio_remove(struct platform_device *pdev)
286 {
287 	struct resource *res;
288 	if (gpio_ba) {
289 		int err;
290 
291 		err  = gpiochip_remove(&sch_gpio_core);
292 		if (err)
293 			dev_err(&pdev->dev, "%s failed, %d\n",
294 				"gpiochip_remove()", err);
295 		err = gpiochip_remove(&sch_gpio_resume);
296 		if (err)
297 			dev_err(&pdev->dev, "%s failed, %d\n",
298 				"gpiochip_remove()", err);
299 
300 		res = platform_get_resource(pdev, IORESOURCE_IO, 0);
301 
302 		release_region(res->start, resource_size(res));
303 		gpio_ba = 0;
304 
305 		return err;
306 	}
307 
308 	return 0;
309 }
310 
311 static struct platform_driver sch_gpio_driver = {
312 	.driver = {
313 		.name = "sch_gpio",
314 		.owner = THIS_MODULE,
315 	},
316 	.probe		= sch_gpio_probe,
317 	.remove		= sch_gpio_remove,
318 };
319 
320 module_platform_driver(sch_gpio_driver);
321 
322 MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>");
323 MODULE_DESCRIPTION("GPIO interface for Intel Poulsbo SCH");
324 MODULE_LICENSE("GPL");
325 MODULE_ALIAS("platform:sch_gpio");
326