Version:  2.0.40 2.2.26 2.4.37 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18

Linux/drivers/leds/leds-ns2.c

  1 /*
  2  * leds-ns2.c - Driver for the Network Space v2 (and parents) dual-GPIO LED
  3  *
  4  * Copyright (C) 2010 LaCie
  5  *
  6  * Author: Simon Guinot <sguinot@lacie.com>
  7  *
  8  * Based on leds-gpio.c by Raphael Assenat <raph@8d.com>
  9  *
 10  * This program is free software; you can redistribute it and/or modify
 11  * it under the terms of the GNU General Public License as published by
 12  * the Free Software Foundation; either version 2 of the License, or
 13  * (at your option) any later version.
 14  *
 15  * This program is distributed in the hope that it will be useful,
 16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
 17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 18  * GNU General Public License for more details.
 19  *
 20  * You should have received a copy of the GNU General Public License
 21  * along with this program; if not, write to the Free Software
 22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 23  */
 24 
 25 #include <linux/kernel.h>
 26 #include <linux/platform_device.h>
 27 #include <linux/slab.h>
 28 #include <linux/gpio.h>
 29 #include <linux/leds.h>
 30 #include <linux/module.h>
 31 #include <linux/platform_data/leds-kirkwood-ns2.h>
 32 #include <linux/of.h>
 33 #include <linux/of_gpio.h>
 34 
 35 /*
 36  * The Network Space v2 dual-GPIO LED is wired to a CPLD and can blink in
 37  * relation with the SATA activity. This capability is exposed through the
 38  * "sata" sysfs attribute.
 39  *
 40  * The following array detail the different LED registers and the combination
 41  * of their possible values:
 42  *
 43  *  cmd_led   |  slow_led  | /SATA active | LED state
 44  *            |            |              |
 45  *     1      |     0      |      x       |  off
 46  *     -      |     1      |      x       |  on
 47  *     0      |     0      |      1       |  on
 48  *     0      |     0      |      0       |  blink (rate 300ms)
 49  */
 50 
 51 enum ns2_led_modes {
 52         NS_V2_LED_OFF,
 53         NS_V2_LED_ON,
 54         NS_V2_LED_SATA,
 55 };
 56 
 57 struct ns2_led_mode_value {
 58         enum ns2_led_modes      mode;
 59         int                     cmd_level;
 60         int                     slow_level;
 61 };
 62 
 63 static struct ns2_led_mode_value ns2_led_modval[] = {
 64         { NS_V2_LED_OFF , 1, 0 },
 65         { NS_V2_LED_ON  , 0, 1 },
 66         { NS_V2_LED_ON  , 1, 1 },
 67         { NS_V2_LED_SATA, 0, 0 },
 68 };
 69 
 70 struct ns2_led_data {
 71         struct led_classdev     cdev;
 72         unsigned                cmd;
 73         unsigned                slow;
 74         unsigned char           sata; /* True when SATA mode active. */
 75         rwlock_t                rw_lock; /* Lock GPIOs. */
 76 };
 77 
 78 static int ns2_led_get_mode(struct ns2_led_data *led_dat,
 79                             enum ns2_led_modes *mode)
 80 {
 81         int i;
 82         int ret = -EINVAL;
 83         int cmd_level;
 84         int slow_level;
 85 
 86         read_lock_irq(&led_dat->rw_lock);
 87 
 88         cmd_level = gpio_get_value(led_dat->cmd);
 89         slow_level = gpio_get_value(led_dat->slow);
 90 
 91         for (i = 0; i < ARRAY_SIZE(ns2_led_modval); i++) {
 92                 if (cmd_level == ns2_led_modval[i].cmd_level &&
 93                     slow_level == ns2_led_modval[i].slow_level) {
 94                         *mode = ns2_led_modval[i].mode;
 95                         ret = 0;
 96                         break;
 97                 }
 98         }
 99 
100         read_unlock_irq(&led_dat->rw_lock);
101 
102         return ret;
103 }
104 
105 static void ns2_led_set_mode(struct ns2_led_data *led_dat,
106                              enum ns2_led_modes mode)
107 {
108         int i;
109         unsigned long flags;
110 
111         write_lock_irqsave(&led_dat->rw_lock, flags);
112 
113         for (i = 0; i < ARRAY_SIZE(ns2_led_modval); i++) {
114                 if (mode == ns2_led_modval[i].mode) {
115                         gpio_set_value(led_dat->cmd,
116                                        ns2_led_modval[i].cmd_level);
117                         gpio_set_value(led_dat->slow,
118                                        ns2_led_modval[i].slow_level);
119                 }
120         }
121 
122         write_unlock_irqrestore(&led_dat->rw_lock, flags);
123 }
124 
125 static void ns2_led_set(struct led_classdev *led_cdev,
126                         enum led_brightness value)
127 {
128         struct ns2_led_data *led_dat =
129                 container_of(led_cdev, struct ns2_led_data, cdev);
130         enum ns2_led_modes mode;
131 
132         if (value == LED_OFF)
133                 mode = NS_V2_LED_OFF;
134         else if (led_dat->sata)
135                 mode = NS_V2_LED_SATA;
136         else
137                 mode = NS_V2_LED_ON;
138 
139         ns2_led_set_mode(led_dat, mode);
140 }
141 
142 static ssize_t ns2_led_sata_store(struct device *dev,
143                                   struct device_attribute *attr,
144                                   const char *buff, size_t count)
145 {
146         struct led_classdev *led_cdev = dev_get_drvdata(dev);
147         struct ns2_led_data *led_dat =
148                 container_of(led_cdev, struct ns2_led_data, cdev);
149         int ret;
150         unsigned long enable;
151         enum ns2_led_modes mode;
152 
153         ret = kstrtoul(buff, 10, &enable);
154         if (ret < 0)
155                 return ret;
156 
157         enable = !!enable;
158 
159         if (led_dat->sata == enable)
160                 return count;
161 
162         ret = ns2_led_get_mode(led_dat, &mode);
163         if (ret < 0)
164                 return ret;
165 
166         if (enable && mode == NS_V2_LED_ON)
167                 ns2_led_set_mode(led_dat, NS_V2_LED_SATA);
168         if (!enable && mode == NS_V2_LED_SATA)
169                 ns2_led_set_mode(led_dat, NS_V2_LED_ON);
170 
171         led_dat->sata = enable;
172 
173         return count;
174 }
175 
176 static ssize_t ns2_led_sata_show(struct device *dev,
177                                  struct device_attribute *attr, char *buf)
178 {
179         struct led_classdev *led_cdev = dev_get_drvdata(dev);
180         struct ns2_led_data *led_dat =
181                 container_of(led_cdev, struct ns2_led_data, cdev);
182 
183         return sprintf(buf, "%d\n", led_dat->sata);
184 }
185 
186 static DEVICE_ATTR(sata, 0644, ns2_led_sata_show, ns2_led_sata_store);
187 
188 static struct attribute *ns2_led_attrs[] = {
189         &dev_attr_sata.attr,
190         NULL
191 };
192 ATTRIBUTE_GROUPS(ns2_led);
193 
194 static int
195 create_ns2_led(struct platform_device *pdev, struct ns2_led_data *led_dat,
196                const struct ns2_led *template)
197 {
198         int ret;
199         enum ns2_led_modes mode;
200 
201         ret = devm_gpio_request_one(&pdev->dev, template->cmd,
202                         gpio_get_value(template->cmd) ?
203                         GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW,
204                         template->name);
205         if (ret) {
206                 dev_err(&pdev->dev, "%s: failed to setup command GPIO\n",
207                         template->name);
208                 return ret;
209         }
210 
211         ret = devm_gpio_request_one(&pdev->dev, template->slow,
212                         gpio_get_value(template->slow) ?
213                         GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW,
214                         template->name);
215         if (ret) {
216                 dev_err(&pdev->dev, "%s: failed to setup slow GPIO\n",
217                         template->name);
218                 return ret;
219         }
220 
221         rwlock_init(&led_dat->rw_lock);
222 
223         led_dat->cdev.name = template->name;
224         led_dat->cdev.default_trigger = template->default_trigger;
225         led_dat->cdev.blink_set = NULL;
226         led_dat->cdev.brightness_set = ns2_led_set;
227         led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
228         led_dat->cdev.groups = ns2_led_groups;
229         led_dat->cmd = template->cmd;
230         led_dat->slow = template->slow;
231 
232         ret = ns2_led_get_mode(led_dat, &mode);
233         if (ret < 0)
234                 return ret;
235 
236         /* Set LED initial state. */
237         led_dat->sata = (mode == NS_V2_LED_SATA) ? 1 : 0;
238         led_dat->cdev.brightness =
239                 (mode == NS_V2_LED_OFF) ? LED_OFF : LED_FULL;
240 
241         ret = led_classdev_register(&pdev->dev, &led_dat->cdev);
242         if (ret < 0)
243                 return ret;
244 
245         return 0;
246 }
247 
248 static void delete_ns2_led(struct ns2_led_data *led_dat)
249 {
250         led_classdev_unregister(&led_dat->cdev);
251 }
252 
253 #ifdef CONFIG_OF_GPIO
254 /*
255  * Translate OpenFirmware node properties into platform_data.
256  */
257 static int
258 ns2_leds_get_of_pdata(struct device *dev, struct ns2_led_platform_data *pdata)
259 {
260         struct device_node *np = dev->of_node;
261         struct device_node *child;
262         struct ns2_led *leds;
263         int num_leds = 0;
264         int i = 0;
265 
266         num_leds = of_get_child_count(np);
267         if (!num_leds)
268                 return -ENODEV;
269 
270         leds = devm_kzalloc(dev, num_leds * sizeof(struct ns2_led),
271                             GFP_KERNEL);
272         if (!leds)
273                 return -ENOMEM;
274 
275         for_each_child_of_node(np, child) {
276                 const char *string;
277                 int ret;
278 
279                 ret = of_get_named_gpio(child, "cmd-gpio", 0);
280                 if (ret < 0)
281                         return ret;
282                 leds[i].cmd = ret;
283                 ret = of_get_named_gpio(child, "slow-gpio", 0);
284                 if (ret < 0)
285                         return ret;
286                 leds[i].slow = ret;
287                 ret = of_property_read_string(child, "label", &string);
288                 leds[i].name = (ret == 0) ? string : child->name;
289                 ret = of_property_read_string(child, "linux,default-trigger",
290                                               &string);
291                 if (ret == 0)
292                         leds[i].default_trigger = string;
293 
294                 i++;
295         }
296 
297         pdata->leds = leds;
298         pdata->num_leds = num_leds;
299 
300         return 0;
301 }
302 
303 static const struct of_device_id of_ns2_leds_match[] = {
304         { .compatible = "lacie,ns2-leds", },
305         {},
306 };
307 #endif /* CONFIG_OF_GPIO */
308 
309 struct ns2_led_priv {
310         int num_leds;
311         struct ns2_led_data leds_data[];
312 };
313 
314 static inline int sizeof_ns2_led_priv(int num_leds)
315 {
316         return sizeof(struct ns2_led_priv) +
317                       (sizeof(struct ns2_led_data) * num_leds);
318 }
319 
320 static int ns2_led_probe(struct platform_device *pdev)
321 {
322         struct ns2_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
323         struct ns2_led_priv *priv;
324         int i;
325         int ret;
326 
327 #ifdef CONFIG_OF_GPIO
328         if (!pdata) {
329                 pdata = devm_kzalloc(&pdev->dev,
330                                      sizeof(struct ns2_led_platform_data),
331                                      GFP_KERNEL);
332                 if (!pdata)
333                         return -ENOMEM;
334 
335                 ret = ns2_leds_get_of_pdata(&pdev->dev, pdata);
336                 if (ret)
337                         return ret;
338         }
339 #else
340         if (!pdata)
341                 return -EINVAL;
342 #endif /* CONFIG_OF_GPIO */
343 
344         priv = devm_kzalloc(&pdev->dev,
345                             sizeof_ns2_led_priv(pdata->num_leds), GFP_KERNEL);
346         if (!priv)
347                 return -ENOMEM;
348         priv->num_leds = pdata->num_leds;
349 
350         for (i = 0; i < priv->num_leds; i++) {
351                 ret = create_ns2_led(pdev, &priv->leds_data[i],
352                                      &pdata->leds[i]);
353                 if (ret < 0) {
354                         for (i = i - 1; i >= 0; i--)
355                                 delete_ns2_led(&priv->leds_data[i]);
356                         return ret;
357                 }
358         }
359 
360         platform_set_drvdata(pdev, priv);
361 
362         return 0;
363 }
364 
365 static int ns2_led_remove(struct platform_device *pdev)
366 {
367         int i;
368         struct ns2_led_priv *priv;
369 
370         priv = platform_get_drvdata(pdev);
371 
372         for (i = 0; i < priv->num_leds; i++)
373                 delete_ns2_led(&priv->leds_data[i]);
374 
375         return 0;
376 }
377 
378 static struct platform_driver ns2_led_driver = {
379         .probe          = ns2_led_probe,
380         .remove         = ns2_led_remove,
381         .driver         = {
382                 .name           = "leds-ns2",
383                 .owner          = THIS_MODULE,
384                 .of_match_table = of_match_ptr(of_ns2_leds_match),
385         },
386 };
387 
388 module_platform_driver(ns2_led_driver);
389 
390 MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>");
391 MODULE_DESCRIPTION("Network Space v2 LED driver");
392 MODULE_LICENSE("GPL");
393 MODULE_ALIAS("platform:leds-ns2");
394 

This page was automatically generated by LXR 0.3.1 (source).  •  Linux is a registered trademark of Linus Torvalds  •  Contact us