aboutsummaryrefslogtreecommitdiff
path: root/drivers/leds/leds-ns2.c
blob: c7a4230233ea991e660dabf6f55ceedff9c5c381 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
/*
 * leds-ns2.c - Driver for the Network Space v2 (and parents) dual-GPIO LED
 *
 * Copyright (C) 2010 LaCie
 *
 * Author: Simon Guinot <sguinot@lacie.com>
 *
 * Based on leds-gpio.c by Raphael Assenat <raph@8d.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/gpio.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/platform_data/leds-kirkwood-ns2.h>
#include <linux/of.h>
#include <linux/of_gpio.h>

/*
 * The Network Space v2 dual-GPIO LED is wired to a CPLD and can blink in
 * relation with the SATA activity. This capability is exposed through the
 * "sata" sysfs attribute.
 *
 * The following array detail the different LED registers and the combination
 * of their possible values:
 *
 *  cmd_led   |  slow_led  | /SATA active | LED state
 *            |            |              |
 *     1      |     0      |      x       |  off
 *     -      |     1      |      x       |  on
 *     0      |     0      |      1       |  on
 *     0      |     0      |      0       |  blink (rate 300ms)
 */

enum ns2_led_modes {
	NS_V2_LED_OFF,
	NS_V2_LED_ON,
	NS_V2_LED_SATA,
};

struct ns2_led_mode_value {
	enum ns2_led_modes	mode;
	int			cmd_level;
	int			slow_level;
};

static struct ns2_led_mode_value ns2_led_modval[] = {
	{ NS_V2_LED_OFF	, 1, 0 },
	{ NS_V2_LED_ON	, 0, 1 },
	{ NS_V2_LED_ON	, 1, 1 },
	{ NS_V2_LED_SATA, 0, 0 },
};

struct ns2_led_data {
	struct led_classdev	cdev;
	unsigned		cmd;
	unsigned		slow;
	unsigned char		sata; /* True when SATA mode active. */
	rwlock_t		rw_lock; /* Lock GPIOs. */
};

static int ns2_led_get_mode(struct ns2_led_data *led_dat,
			    enum ns2_led_modes *mode)
{
	int i;
	int ret = -EINVAL;
	int cmd_level;
	int slow_level;

	read_lock_irq(&led_dat->rw_lock);

	cmd_level = gpio_get_value(led_dat->cmd);
	slow_level = gpio_get_value(led_dat->slow);

	for (i = 0; i < ARRAY_SIZE(ns2_led_modval); i++) {
		if (cmd_level == ns2_led_modval[i].cmd_level &&
		    slow_level == ns2_led_modval[i].slow_level) {
			*mode = ns2_led_modval[i].mode;
			ret = 0;
			break;
		}
	}

	read_unlock_irq(&led_dat->rw_lock);

	return ret;
}

static void ns2_led_set_mode(struct ns2_led_data *led_dat,
			     enum ns2_led_modes mode)
{
	int i;
	unsigned long flags;

	write_lock_irqsave(&led_dat->rw_lock, flags);

	for (i = 0; i < ARRAY_SIZE(ns2_led_modval); i++) {
		if (mode == ns2_led_modval[i].mode) {
			gpio_set_value(led_dat->cmd,
				       ns2_led_modval[i].cmd_level);
			gpio_set_value(led_dat->slow,
				       ns2_led_modval[i].slow_level);
		}
	}

	write_unlock_irqrestore(&led_dat->rw_lock, flags);
}

static void ns2_led_set(struct led_classdev *led_cdev,
			enum led_brightness value)
{
	struct ns2_led_data *led_dat =
		container_of(led_cdev, struct ns2_led_data, cdev);
	enum ns2_led_modes mode;

	if (value == LED_OFF)
		mode = NS_V2_LED_OFF;
	else if (led_dat->sata)
		mode = NS_V2_LED_SATA;
	else
		mode = NS_V2_LED_ON;

	ns2_led_set_mode(led_dat, mode);
}

static ssize_t ns2_led_sata_store(struct device *dev,
				  struct device_attribute *attr,
				  const char *buff, size_t count)
{
	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	struct ns2_led_data *led_dat =
		container_of(led_cdev, struct ns2_led_data, cdev);
	int ret;
	unsigned long enable;
	enum ns2_led_modes mode;

	ret = kstrtoul(buff, 10, &enable);
	if (ret < 0)
		return ret;

	enable = !!enable;

	if (led_dat->sata == enable)
		return count;

	ret = ns2_led_get_mode(led_dat, &mode);
	if (ret < 0)
		return ret;

	if (enable && mode == NS_V2_LED_ON)
		ns2_led_set_mode(led_dat, NS_V2_LED_SATA);
	if (!enable && mode == NS_V2_LED_SATA)
		ns2_led_set_mode(led_dat, NS_V2_LED_ON);

	led_dat->sata = enable;

	return count;
}

static ssize_t ns2_led_sata_show(struct device *dev,
				 struct device_attribute *attr, char *buf)
{
	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	struct ns2_led_data *led_dat =
		container_of(led_cdev, struct ns2_led_data, cdev);

	return sprintf(buf, "%d\n", led_dat->sata);
}

static DEVICE_ATTR(sata, 0644, ns2_led_sata_show, ns2_led_sata_store);

static int
create_ns2_led(struct platform_device *pdev, struct ns2_led_data *led_dat,
	       const struct ns2_led *template)
{
	int ret;
	enum ns2_led_modes mode;

	ret = devm_gpio_request_one(&pdev->dev, template->cmd,
			gpio_get_value(template->cmd) ?
			GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW,
			template->name);
	if (ret) {
		dev_err(&pdev->dev, "%s: failed to setup command GPIO\n",
			template->name);
		return ret;
	}

	ret = devm_gpio_request_one(&pdev->dev, template->slow,
			gpio_get_value(template->slow) ?
			GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW,
			template->name);
	if (ret) {
		dev_err(&pdev->dev, "%s: failed to setup slow GPIO\n",
			template->name);
		return ret;
	}

	rwlock_init(&led_dat->rw_lock);

	led_dat->cdev.name = template->name;
	led_dat->cdev.default_trigger = template->default_trigger;
	led_dat->cdev.blink_set = NULL;
	led_dat->cdev.brightness_set = ns2_led_set;
	led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
	led_dat->cmd = template->cmd;
	led_dat->slow = template->slow;

	ret = ns2_led_get_mode(led_dat, &mode);
	if (ret < 0)
		return ret;

	/* Set LED initial state. */
	led_dat->sata = (mode == NS_V2_LED_SATA) ? 1 : 0;
	led_dat->cdev.brightness =
		(mode == NS_V2_LED_OFF) ? LED_OFF : LED_FULL;

	ret = led_classdev_register(&pdev->dev, &led_dat->cdev);
	if (ret < 0)
		return ret;

	ret = device_create_file(led_dat->cdev.dev, &dev_attr_sata);
	if (ret < 0)
		goto err_free_cdev;

	return 0;

err_free_cdev:
	led_classdev_unregister(&led_dat->cdev);
	return ret;
}

static void delete_ns2_led(struct ns2_led_data *led_dat)
{
	device_remove_file(led_dat->cdev.dev, &dev_attr_sata);
	led_classdev_unregister(&led_dat->cdev);
}

#ifdef CONFIG_OF_GPIO
/*
 * Translate OpenFirmware node properties into platform_data.
 */
static int
ns2_leds_get_of_pdata(struct device *dev, struct ns2_led_platform_data *pdata)
{
	struct device_node *np = dev->of_node;
	struct device_node *child;
	struct ns2_led *leds;
	int num_leds = 0;
	int i = 0;

	num_leds = of_get_child_count(np);
	if (!num_leds)
		return -ENODEV;

	leds = devm_kzalloc(dev, num_leds * sizeof(struct ns2_led),
			    GFP_KERNEL);
	if (!leds)
		return -ENOMEM;

	for_each_child_of_node(np, child) {
		const char *string;
		int ret;

		ret = of_get_named_gpio(child, "cmd-gpio", 0);
		if (ret < 0)
			return ret;
		leds[i].cmd = ret;
		ret = of_get_named_gpio(child, "slow-gpio", 0);
		if (ret < 0)
			return ret;
		leds[i].slow = ret;
		ret = of_property_read_string(child, "label", &string);
		leds[i].name = (ret == 0) ? string : child->name;
		ret = of_property_read_string(child, "linux,default-trigger",
					      &string);
		if (ret == 0)
			leds[i].default_trigger = string;

		i++;
	}

	pdata->leds = leds;
	pdata->num_leds = num_leds;

	return 0;
}

static const struct of_device_id of_ns2_leds_match[] = {
	{ .compatible = "lacie,ns2-leds", },
	{},
};
#endif /* CONFIG_OF_GPIO */

struct ns2_led_priv {
	int num_leds;
	struct ns2_led_data leds_data[];
};

static inline int sizeof_ns2_led_priv(int num_leds)
{
	return sizeof(struct ns2_led_priv) +
		      (sizeof(struct ns2_led_data) * num_leds);
}

static int ns2_led_probe(struct platform_device *pdev)
{
	struct ns2_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
	struct ns2_led_priv *priv;
	int i;
	int ret;

#ifdef CONFIG_OF_GPIO
	if (!pdata) {
		pdata = devm_kzalloc(&pdev->dev,
				     sizeof(struct ns2_led_platform_data),
				     GFP_KERNEL);
		if (!pdata)
			return -ENOMEM;

		ret = ns2_leds_get_of_pdata(&pdev->dev, pdata);
		if (ret)
			return ret;
	}
#else
	if (!pdata)
		return -EINVAL;
#endif /* CONFIG_OF_GPIO */

	priv = devm_kzalloc(&pdev->dev,
			    sizeof_ns2_led_priv(pdata->num_leds), GFP_KERNEL);
	if (!priv)
		return -ENOMEM;
	priv->num_leds = pdata->num_leds;

	for (i = 0; i < priv->num_leds; i++) {
		ret = create_ns2_led(pdev, &priv->leds_data[i],
				     &pdata->leds[i]);
		if (ret < 0) {
			for (i = i - 1; i >= 0; i--)
				delete_ns2_led(&priv->leds_data[i]);
			return ret;
		}
	}

	platform_set_drvdata(pdev, priv);

	return 0;
}

static int ns2_led_remove(struct platform_device *pdev)
{
	int i;
	struct ns2_led_priv *priv;

	priv = platform_get_drvdata(pdev);

	for (i = 0; i < priv->num_leds; i++)
		delete_ns2_led(&priv->leds_data[i]);

	return 0;
}

static struct platform_driver ns2_led_driver = {
	.probe		= ns2_led_probe,
	.remove		= ns2_led_remove,
	.driver		= {
		.name		= "leds-ns2",
		.owner		= THIS_MODULE,
		.of_match_table	= of_match_ptr(of_ns2_leds_match),
	},
};

module_platform_driver(ns2_led_driver);

MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>");
MODULE_DESCRIPTION("Network Space v2 LED driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:leds-ns2");