1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * leds-ns2.c - Driver for the Network Space v2 (and parents) dual-GPIO LED
4 *
5 * Copyright (C) 2010 LaCie
6 *
7 * Author: Simon Guinot <sguinot@lacie.com>
8 *
9 * Based on leds-gpio.c by Raphael Assenat <raph@8d.com>
10 */
11
12 #include <linux/kernel.h>
13 #include <linux/platform_device.h>
14 #include <linux/slab.h>
15 #include <linux/gpio.h>
16 #include <linux/leds.h>
17 #include <linux/module.h>
18 #include <linux/platform_data/leds-kirkwood-ns2.h>
19 #include <linux/of.h>
20 #include <linux/of_gpio.h>
21 #include "leds.h"
22
23 /*
24 * The Network Space v2 dual-GPIO LED is wired to a CPLD. Three different LED
25 * modes are available: off, on and SATA activity blinking. The LED modes are
26 * controlled through two GPIOs (command and slow): each combination of values
27 * for the command/slow GPIOs corresponds to a LED mode.
28 */
29
30 struct ns2_led_data {
31 struct led_classdev cdev;
32 unsigned int cmd;
33 unsigned int slow;
34 bool can_sleep;
35 unsigned char sata; /* True when SATA mode active. */
36 rwlock_t rw_lock; /* Lock GPIOs. */
37 int num_modes;
38 struct ns2_led_modval *modval;
39 };
40
ns2_led_get_mode(struct ns2_led_data * led_dat,enum ns2_led_modes * mode)41 static int ns2_led_get_mode(struct ns2_led_data *led_dat,
42 enum ns2_led_modes *mode)
43 {
44 int i;
45 int ret = -EINVAL;
46 int cmd_level;
47 int slow_level;
48
49 cmd_level = gpio_get_value_cansleep(led_dat->cmd);
50 slow_level = gpio_get_value_cansleep(led_dat->slow);
51
52 for (i = 0; i < led_dat->num_modes; i++) {
53 if (cmd_level == led_dat->modval[i].cmd_level &&
54 slow_level == led_dat->modval[i].slow_level) {
55 *mode = led_dat->modval[i].mode;
56 ret = 0;
57 break;
58 }
59 }
60
61 return ret;
62 }
63
ns2_led_set_mode(struct ns2_led_data * led_dat,enum ns2_led_modes mode)64 static void ns2_led_set_mode(struct ns2_led_data *led_dat,
65 enum ns2_led_modes mode)
66 {
67 int i;
68 bool found = false;
69 unsigned long flags;
70
71 for (i = 0; i < led_dat->num_modes; i++)
72 if (mode == led_dat->modval[i].mode) {
73 found = true;
74 break;
75 }
76
77 if (!found)
78 return;
79
80 write_lock_irqsave(&led_dat->rw_lock, flags);
81
82 if (!led_dat->can_sleep) {
83 gpio_set_value(led_dat->cmd,
84 led_dat->modval[i].cmd_level);
85 gpio_set_value(led_dat->slow,
86 led_dat->modval[i].slow_level);
87 goto exit_unlock;
88 }
89
90 gpio_set_value_cansleep(led_dat->cmd, led_dat->modval[i].cmd_level);
91 gpio_set_value_cansleep(led_dat->slow, led_dat->modval[i].slow_level);
92
93 exit_unlock:
94 write_unlock_irqrestore(&led_dat->rw_lock, flags);
95 }
96
ns2_led_set(struct led_classdev * led_cdev,enum led_brightness value)97 static void ns2_led_set(struct led_classdev *led_cdev,
98 enum led_brightness value)
99 {
100 struct ns2_led_data *led_dat =
101 container_of(led_cdev, struct ns2_led_data, cdev);
102 enum ns2_led_modes mode;
103
104 if (value == LED_OFF)
105 mode = NS_V2_LED_OFF;
106 else if (led_dat->sata)
107 mode = NS_V2_LED_SATA;
108 else
109 mode = NS_V2_LED_ON;
110
111 ns2_led_set_mode(led_dat, mode);
112 }
113
ns2_led_set_blocking(struct led_classdev * led_cdev,enum led_brightness value)114 static int ns2_led_set_blocking(struct led_classdev *led_cdev,
115 enum led_brightness value)
116 {
117 ns2_led_set(led_cdev, value);
118 return 0;
119 }
120
ns2_led_sata_store(struct device * dev,struct device_attribute * attr,const char * buff,size_t count)121 static ssize_t ns2_led_sata_store(struct device *dev,
122 struct device_attribute *attr,
123 const char *buff, size_t count)
124 {
125 struct led_classdev *led_cdev = dev_get_drvdata(dev);
126 struct ns2_led_data *led_dat =
127 container_of(led_cdev, struct ns2_led_data, cdev);
128 int ret;
129 unsigned long enable;
130
131 ret = kstrtoul(buff, 10, &enable);
132 if (ret < 0)
133 return ret;
134
135 enable = !!enable;
136
137 if (led_dat->sata == enable)
138 goto exit;
139
140 led_dat->sata = enable;
141
142 if (!led_get_brightness(led_cdev))
143 goto exit;
144
145 if (enable)
146 ns2_led_set_mode(led_dat, NS_V2_LED_SATA);
147 else
148 ns2_led_set_mode(led_dat, NS_V2_LED_ON);
149
150 exit:
151 return count;
152 }
153
ns2_led_sata_show(struct device * dev,struct device_attribute * attr,char * buf)154 static ssize_t ns2_led_sata_show(struct device *dev,
155 struct device_attribute *attr, char *buf)
156 {
157 struct led_classdev *led_cdev = dev_get_drvdata(dev);
158 struct ns2_led_data *led_dat =
159 container_of(led_cdev, struct ns2_led_data, cdev);
160
161 return sprintf(buf, "%d\n", led_dat->sata);
162 }
163
164 static DEVICE_ATTR(sata, 0644, ns2_led_sata_show, ns2_led_sata_store);
165
166 static struct attribute *ns2_led_attrs[] = {
167 &dev_attr_sata.attr,
168 NULL
169 };
170 ATTRIBUTE_GROUPS(ns2_led);
171
172 static int
create_ns2_led(struct platform_device * pdev,struct ns2_led_data * led_dat,const struct ns2_led * template)173 create_ns2_led(struct platform_device *pdev, struct ns2_led_data *led_dat,
174 const struct ns2_led *template)
175 {
176 int ret;
177 enum ns2_led_modes mode;
178
179 ret = devm_gpio_request_one(&pdev->dev, template->cmd,
180 gpio_get_value_cansleep(template->cmd) ?
181 GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW,
182 template->name);
183 if (ret) {
184 dev_err(&pdev->dev, "%s: failed to setup command GPIO\n",
185 template->name);
186 return ret;
187 }
188
189 ret = devm_gpio_request_one(&pdev->dev, template->slow,
190 gpio_get_value_cansleep(template->slow) ?
191 GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW,
192 template->name);
193 if (ret) {
194 dev_err(&pdev->dev, "%s: failed to setup slow GPIO\n",
195 template->name);
196 return ret;
197 }
198
199 rwlock_init(&led_dat->rw_lock);
200
201 led_dat->cdev.name = template->name;
202 led_dat->cdev.default_trigger = template->default_trigger;
203 led_dat->cdev.blink_set = NULL;
204 led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
205 led_dat->cdev.groups = ns2_led_groups;
206 led_dat->cmd = template->cmd;
207 led_dat->slow = template->slow;
208 led_dat->can_sleep = gpio_cansleep(led_dat->cmd) |
209 gpio_cansleep(led_dat->slow);
210 if (led_dat->can_sleep)
211 led_dat->cdev.brightness_set_blocking = ns2_led_set_blocking;
212 else
213 led_dat->cdev.brightness_set = ns2_led_set;
214 led_dat->modval = template->modval;
215 led_dat->num_modes = template->num_modes;
216
217 ret = ns2_led_get_mode(led_dat, &mode);
218 if (ret < 0)
219 return ret;
220
221 /* Set LED initial state. */
222 led_dat->sata = (mode == NS_V2_LED_SATA) ? 1 : 0;
223 led_dat->cdev.brightness =
224 (mode == NS_V2_LED_OFF) ? LED_OFF : LED_FULL;
225
226 ret = led_classdev_register(&pdev->dev, &led_dat->cdev);
227 if (ret < 0)
228 return ret;
229
230 return 0;
231 }
232
delete_ns2_led(struct ns2_led_data * led_dat)233 static void delete_ns2_led(struct ns2_led_data *led_dat)
234 {
235 led_classdev_unregister(&led_dat->cdev);
236 }
237
238 #ifdef CONFIG_OF_GPIO
239 /*
240 * Translate OpenFirmware node properties into platform_data.
241 */
242 static int
ns2_leds_get_of_pdata(struct device * dev,struct ns2_led_platform_data * pdata)243 ns2_leds_get_of_pdata(struct device *dev, struct ns2_led_platform_data *pdata)
244 {
245 struct device_node *np = dev->of_node;
246 struct device_node *child;
247 struct ns2_led *led, *leds;
248 int ret, num_leds = 0;
249
250 num_leds = of_get_child_count(np);
251 if (!num_leds)
252 return -ENODEV;
253
254 leds = devm_kcalloc(dev, num_leds, sizeof(struct ns2_led),
255 GFP_KERNEL);
256 if (!leds)
257 return -ENOMEM;
258
259 led = leds;
260 for_each_child_of_node(np, child) {
261 const char *string;
262 int i, num_modes;
263 struct ns2_led_modval *modval;
264
265 ret = of_get_named_gpio(child, "cmd-gpio", 0);
266 if (ret < 0)
267 goto err_node_put;
268 led->cmd = ret;
269 ret = of_get_named_gpio(child, "slow-gpio", 0);
270 if (ret < 0)
271 goto err_node_put;
272 led->slow = ret;
273 ret = of_property_read_string(child, "label", &string);
274 led->name = (ret == 0) ? string : child->name;
275 ret = of_property_read_string(child, "linux,default-trigger",
276 &string);
277 if (ret == 0)
278 led->default_trigger = string;
279
280 ret = of_property_count_u32_elems(child, "modes-map");
281 if (ret < 0 || ret % 3) {
282 dev_err(dev,
283 "Missing or malformed modes-map property\n");
284 ret = -EINVAL;
285 goto err_node_put;
286 }
287
288 num_modes = ret / 3;
289 modval = devm_kcalloc(dev,
290 num_modes,
291 sizeof(struct ns2_led_modval),
292 GFP_KERNEL);
293 if (!modval) {
294 ret = -ENOMEM;
295 goto err_node_put;
296 }
297
298 for (i = 0; i < num_modes; i++) {
299 of_property_read_u32_index(child,
300 "modes-map", 3 * i,
301 (u32 *) &modval[i].mode);
302 of_property_read_u32_index(child,
303 "modes-map", 3 * i + 1,
304 (u32 *) &modval[i].cmd_level);
305 of_property_read_u32_index(child,
306 "modes-map", 3 * i + 2,
307 (u32 *) &modval[i].slow_level);
308 }
309
310 led->num_modes = num_modes;
311 led->modval = modval;
312
313 led++;
314 }
315
316 pdata->leds = leds;
317 pdata->num_leds = num_leds;
318
319 return 0;
320
321 err_node_put:
322 of_node_put(child);
323 return ret;
324 }
325
326 static const struct of_device_id of_ns2_leds_match[] = {
327 { .compatible = "lacie,ns2-leds", },
328 {},
329 };
330 MODULE_DEVICE_TABLE(of, of_ns2_leds_match);
331 #endif /* CONFIG_OF_GPIO */
332
333 struct ns2_led_priv {
334 int num_leds;
335 struct ns2_led_data leds_data[];
336 };
337
sizeof_ns2_led_priv(int num_leds)338 static inline int sizeof_ns2_led_priv(int num_leds)
339 {
340 return sizeof(struct ns2_led_priv) +
341 (sizeof(struct ns2_led_data) * num_leds);
342 }
343
ns2_led_probe(struct platform_device * pdev)344 static int ns2_led_probe(struct platform_device *pdev)
345 {
346 struct ns2_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
347 struct ns2_led_priv *priv;
348 int i;
349 int ret;
350
351 #ifdef CONFIG_OF_GPIO
352 if (!pdata) {
353 pdata = devm_kzalloc(&pdev->dev,
354 sizeof(struct ns2_led_platform_data),
355 GFP_KERNEL);
356 if (!pdata)
357 return -ENOMEM;
358
359 ret = ns2_leds_get_of_pdata(&pdev->dev, pdata);
360 if (ret)
361 return ret;
362 }
363 #else
364 if (!pdata)
365 return -EINVAL;
366 #endif /* CONFIG_OF_GPIO */
367
368 priv = devm_kzalloc(&pdev->dev,
369 sizeof_ns2_led_priv(pdata->num_leds), GFP_KERNEL);
370 if (!priv)
371 return -ENOMEM;
372 priv->num_leds = pdata->num_leds;
373
374 for (i = 0; i < priv->num_leds; i++) {
375 ret = create_ns2_led(pdev, &priv->leds_data[i],
376 &pdata->leds[i]);
377 if (ret < 0) {
378 for (i = i - 1; i >= 0; i--)
379 delete_ns2_led(&priv->leds_data[i]);
380 return ret;
381 }
382 }
383
384 platform_set_drvdata(pdev, priv);
385
386 return 0;
387 }
388
ns2_led_remove(struct platform_device * pdev)389 static int ns2_led_remove(struct platform_device *pdev)
390 {
391 int i;
392 struct ns2_led_priv *priv;
393
394 priv = platform_get_drvdata(pdev);
395
396 for (i = 0; i < priv->num_leds; i++)
397 delete_ns2_led(&priv->leds_data[i]);
398
399 return 0;
400 }
401
402 static struct platform_driver ns2_led_driver = {
403 .probe = ns2_led_probe,
404 .remove = ns2_led_remove,
405 .driver = {
406 .name = "leds-ns2",
407 .of_match_table = of_match_ptr(of_ns2_leds_match),
408 },
409 };
410
411 module_platform_driver(ns2_led_driver);
412
413 MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>");
414 MODULE_DESCRIPTION("Network Space v2 LED driver");
415 MODULE_LICENSE("GPL");
416 MODULE_ALIAS("platform:leds-ns2");
417