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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * PowerNV LED Driver
4 *
5 * Copyright IBM Corp. 2015
6 *
7 * Author: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
8 * Author: Anshuman Khandual <khandual@linux.vnet.ibm.com>
9 */
10
11#include <linux/leds.h>
12#include <linux/module.h>
13#include <linux/of.h>
14#include <linux/platform_device.h>
15#include <linux/slab.h>
16#include <linux/types.h>
17
18#include <asm/opal.h>
19
20/* Map LED type to description. */
21struct led_type_map {
22 const int type;
23 const char *desc;
24};
25static const struct led_type_map led_type_map[] = {
26 {OPAL_SLOT_LED_TYPE_ID, "identify"},
27 {OPAL_SLOT_LED_TYPE_FAULT, "fault"},
28 {OPAL_SLOT_LED_TYPE_ATTN, "attention"},
29 {-1, NULL},
30};
31
32struct powernv_led_common {
33 /*
34 * By default unload path resets all the LEDs. But on PowerNV
35 * platform we want to retain LED state across reboot as these
36 * are controlled by firmware. Also service processor can modify
37 * the LEDs independent of OS. Hence avoid resetting LEDs in
38 * unload path.
39 */
40 bool led_disabled;
41
42 /* Max supported LED type */
43 __be64 max_led_type;
44
45 /* glabal lock */
46 struct mutex lock;
47};
48
49/* PowerNV LED data */
50struct powernv_led_data {
51 struct led_classdev cdev;
52 char *loc_code; /* LED location code */
53 int led_type; /* OPAL_SLOT_LED_TYPE_* */
54
55 struct powernv_led_common *common;
56};
57
58
59/* Returns OPAL_SLOT_LED_TYPE_* for given led type string */
60static int powernv_get_led_type(const char *led_type_desc)
61{
62 int i;
63
64 for (i = 0; i < ARRAY_SIZE(led_type_map); i++)
65 if (!strcmp(led_type_map[i].desc, led_type_desc))
66 return led_type_map[i].type;
67
68 return -1;
69}
70
71/*
72 * This commits the state change of the requested LED through an OPAL call.
73 * This function is called from work queue task context when ever it gets
74 * scheduled. This function can sleep at opal_async_wait_response call.
75 */
76static int powernv_led_set(struct powernv_led_data *powernv_led,
77 enum led_brightness value)
78{
79 int rc, token;
80 u64 led_mask, led_value = 0;
81 __be64 max_type;
82 struct opal_msg msg;
83 struct device *dev = powernv_led->cdev.dev;
84 struct powernv_led_common *powernv_led_common = powernv_led->common;
85
86 /* Prepare for the OPAL call */
87 max_type = powernv_led_common->max_led_type;
88 led_mask = OPAL_SLOT_LED_STATE_ON << powernv_led->led_type;
89 if (value)
90 led_value = led_mask;
91
92 /* OPAL async call */
93 token = opal_async_get_token_interruptible();
94 if (token < 0) {
95 if (token != -ERESTARTSYS)
96 dev_err(dev, "%s: Couldn't get OPAL async token\n",
97 __func__);
98 return token;
99 }
100
101 rc = opal_leds_set_ind(token, powernv_led->loc_code,
102 led_mask, led_value, &max_type);
103 if (rc != OPAL_ASYNC_COMPLETION) {
104 dev_err(dev, "%s: OPAL set LED call failed for %s [rc=%d]\n",
105 __func__, powernv_led->loc_code, rc);
106 goto out_token;
107 }
108
109 rc = opal_async_wait_response(token, &msg);
110 if (rc) {
111 dev_err(dev,
112 "%s: Failed to wait for the async response [rc=%d]\n",
113 __func__, rc);
114 goto out_token;
115 }
116
117 rc = opal_get_async_rc(msg);
118 if (rc != OPAL_SUCCESS)
119 dev_err(dev, "%s : OAPL async call returned failed [rc=%d]\n",
120 __func__, rc);
121
122out_token:
123 opal_async_release_token(token);
124 return rc;
125}
126
127/*
128 * This function fetches the LED state for a given LED type for
129 * mentioned LED classdev structure.
130 */
131static enum led_brightness powernv_led_get(struct powernv_led_data *powernv_led)
132{
133 int rc;
134 __be64 mask, value, max_type;
135 u64 led_mask, led_value;
136 struct device *dev = powernv_led->cdev.dev;
137 struct powernv_led_common *powernv_led_common = powernv_led->common;
138
139 /* Fetch all LED status */
140 mask = cpu_to_be64(0);
141 value = cpu_to_be64(0);
142 max_type = powernv_led_common->max_led_type;
143
144 rc = opal_leds_get_ind(powernv_led->loc_code,
145 &mask, &value, &max_type);
146 if (rc != OPAL_SUCCESS && rc != OPAL_PARTIAL) {
147 dev_err(dev, "%s: OPAL get led call failed [rc=%d]\n",
148 __func__, rc);
149 return LED_OFF;
150 }
151
152 led_mask = be64_to_cpu(mask);
153 led_value = be64_to_cpu(value);
154
155 /* LED status available */
156 if (!((led_mask >> powernv_led->led_type) & OPAL_SLOT_LED_STATE_ON)) {
157 dev_err(dev, "%s: LED status not available for %s\n",
158 __func__, powernv_led->cdev.name);
159 return LED_OFF;
160 }
161
162 /* LED status value */
163 if ((led_value >> powernv_led->led_type) & OPAL_SLOT_LED_STATE_ON)
164 return LED_FULL;
165
166 return LED_OFF;
167}
168
169/*
170 * LED classdev 'brightness_get' function. This schedules work
171 * to update LED state.
172 */
173static int powernv_brightness_set(struct led_classdev *led_cdev,
174 enum led_brightness value)
175{
176 struct powernv_led_data *powernv_led =
177 container_of(led_cdev, struct powernv_led_data, cdev);
178 struct powernv_led_common *powernv_led_common = powernv_led->common;
179 int rc;
180
181 /* Do not modify LED in unload path */
182 if (powernv_led_common->led_disabled)
183 return 0;
184
185 mutex_lock(&powernv_led_common->lock);
186 rc = powernv_led_set(powernv_led, value);
187 mutex_unlock(&powernv_led_common->lock);
188
189 return rc;
190}
191
192/* LED classdev 'brightness_get' function */
193static enum led_brightness powernv_brightness_get(struct led_classdev *led_cdev)
194{
195 struct powernv_led_data *powernv_led =
196 container_of(led_cdev, struct powernv_led_data, cdev);
197
198 return powernv_led_get(powernv_led);
199}
200
201/*
202 * This function registers classdev structure for any given type of LED on
203 * a given child LED device node.
204 */
205static int powernv_led_create(struct device *dev,
206 struct powernv_led_data *powernv_led,
207 const char *led_type_desc)
208{
209 int rc;
210
211 /* Make sure LED type is supported */
212 powernv_led->led_type = powernv_get_led_type(led_type_desc);
213 if (powernv_led->led_type == -1) {
214 dev_warn(dev, "%s: No support for led type : %s\n",
215 __func__, led_type_desc);
216 return -EINVAL;
217 }
218
219 /* Create the name for classdev */
220 powernv_led->cdev.name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s",
221 powernv_led->loc_code,
222 led_type_desc);
223 if (!powernv_led->cdev.name)
224 return -ENOMEM;
225
226 powernv_led->cdev.brightness_set_blocking = powernv_brightness_set;
227 powernv_led->cdev.brightness_get = powernv_brightness_get;
228 powernv_led->cdev.brightness = LED_OFF;
229 powernv_led->cdev.max_brightness = LED_FULL;
230
231 /* Register the classdev */
232 rc = devm_led_classdev_register(dev, &powernv_led->cdev);
233 if (rc) {
234 dev_err(dev, "%s: Classdev registration failed for %s\n",
235 __func__, powernv_led->cdev.name);
236 }
237
238 return rc;
239}
240
241/* Go through LED device tree node and register LED classdev structure */
242static int powernv_led_classdev(struct platform_device *pdev,
243 struct device_node *led_node,
244 struct powernv_led_common *powernv_led_common)
245{
246 const char *cur = NULL;
247 int rc = -1;
248 struct property *p;
249 struct device_node *np;
250 struct powernv_led_data *powernv_led;
251 struct device *dev = &pdev->dev;
252
253 for_each_available_child_of_node(led_node, np) {
254 p = of_find_property(np, "led-types", NULL);
255
256 while ((cur = of_prop_next_string(p, cur)) != NULL) {
257 powernv_led = devm_kzalloc(dev, sizeof(*powernv_led),
258 GFP_KERNEL);
259 if (!powernv_led) {
260 of_node_put(np);
261 return -ENOMEM;
262 }
263
264 powernv_led->common = powernv_led_common;
265 powernv_led->loc_code = (char *)np->name;
266
267 rc = powernv_led_create(dev, powernv_led, cur);
268 if (rc) {
269 of_node_put(np);
270 return rc;
271 }
272 } /* while end */
273 }
274
275 return rc;
276}
277
278/* Platform driver probe */
279static int powernv_led_probe(struct platform_device *pdev)
280{
281 struct device_node *led_node;
282 struct powernv_led_common *powernv_led_common;
283 struct device *dev = &pdev->dev;
284 int rc;
285
286 led_node = of_find_node_by_path("/ibm,opal/leds");
287 if (!led_node) {
288 dev_err(dev, "%s: LED parent device node not found\n",
289 __func__);
290 return -EINVAL;
291 }
292
293 powernv_led_common = devm_kzalloc(dev, sizeof(*powernv_led_common),
294 GFP_KERNEL);
295 if (!powernv_led_common) {
296 rc = -ENOMEM;
297 goto out;
298 }
299
300 mutex_init(&powernv_led_common->lock);
301 powernv_led_common->max_led_type = cpu_to_be64(OPAL_SLOT_LED_TYPE_MAX);
302
303 platform_set_drvdata(pdev, powernv_led_common);
304
305 rc = powernv_led_classdev(pdev, led_node, powernv_led_common);
306out:
307 of_node_put(led_node);
308 return rc;
309}
310
311/* Platform driver remove */
312static void powernv_led_remove(struct platform_device *pdev)
313{
314 struct powernv_led_common *powernv_led_common;
315
316 /* Disable LED operation */
317 powernv_led_common = platform_get_drvdata(pdev);
318 powernv_led_common->led_disabled = true;
319
320 /* Destroy lock */
321 mutex_destroy(&powernv_led_common->lock);
322
323 dev_info(&pdev->dev, "PowerNV led module unregistered\n");
324}
325
326/* Platform driver property match */
327static const struct of_device_id powernv_led_match[] = {
328 {
329 .compatible = "ibm,opal-v3-led",
330 },
331 {},
332};
333MODULE_DEVICE_TABLE(of, powernv_led_match);
334
335static struct platform_driver powernv_led_driver = {
336 .probe = powernv_led_probe,
337 .remove_new = powernv_led_remove,
338 .driver = {
339 .name = "powernv-led-driver",
340 .of_match_table = powernv_led_match,
341 },
342};
343
344module_platform_driver(powernv_led_driver);
345
346MODULE_LICENSE("GPL v2");
347MODULE_DESCRIPTION("PowerNV LED driver");
348MODULE_AUTHOR("Vasant Hegde <hegdevasant@linux.vnet.ibm.com>");
1/*
2 * PowerNV LED Driver
3 *
4 * Copyright IBM Corp. 2015
5 *
6 * Author: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
7 * Author: Anshuman Khandual <khandual@linux.vnet.ibm.com>
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
13 */
14
15#include <linux/leds.h>
16#include <linux/module.h>
17#include <linux/of.h>
18#include <linux/platform_device.h>
19#include <linux/slab.h>
20#include <linux/types.h>
21
22#include <asm/opal.h>
23
24/* Map LED type to description. */
25struct led_type_map {
26 const int type;
27 const char *desc;
28};
29static const struct led_type_map led_type_map[] = {
30 {OPAL_SLOT_LED_TYPE_ID, "identify"},
31 {OPAL_SLOT_LED_TYPE_FAULT, "fault"},
32 {OPAL_SLOT_LED_TYPE_ATTN, "attention"},
33 {-1, NULL},
34};
35
36struct powernv_led_common {
37 /*
38 * By default unload path resets all the LEDs. But on PowerNV
39 * platform we want to retain LED state across reboot as these
40 * are controlled by firmware. Also service processor can modify
41 * the LEDs independent of OS. Hence avoid resetting LEDs in
42 * unload path.
43 */
44 bool led_disabled;
45
46 /* Max supported LED type */
47 __be64 max_led_type;
48
49 /* glabal lock */
50 struct mutex lock;
51};
52
53/* PowerNV LED data */
54struct powernv_led_data {
55 struct led_classdev cdev;
56 char *loc_code; /* LED location code */
57 int led_type; /* OPAL_SLOT_LED_TYPE_* */
58
59 struct powernv_led_common *common;
60};
61
62
63/* Returns OPAL_SLOT_LED_TYPE_* for given led type string */
64static int powernv_get_led_type(const char *led_type_desc)
65{
66 int i;
67
68 for (i = 0; i < ARRAY_SIZE(led_type_map); i++)
69 if (!strcmp(led_type_map[i].desc, led_type_desc))
70 return led_type_map[i].type;
71
72 return -1;
73}
74
75/*
76 * This commits the state change of the requested LED through an OPAL call.
77 * This function is called from work queue task context when ever it gets
78 * scheduled. This function can sleep at opal_async_wait_response call.
79 */
80static int powernv_led_set(struct powernv_led_data *powernv_led,
81 enum led_brightness value)
82{
83 int rc, token;
84 u64 led_mask, led_value = 0;
85 __be64 max_type;
86 struct opal_msg msg;
87 struct device *dev = powernv_led->cdev.dev;
88 struct powernv_led_common *powernv_led_common = powernv_led->common;
89
90 /* Prepare for the OPAL call */
91 max_type = powernv_led_common->max_led_type;
92 led_mask = OPAL_SLOT_LED_STATE_ON << powernv_led->led_type;
93 if (value)
94 led_value = led_mask;
95
96 /* OPAL async call */
97 token = opal_async_get_token_interruptible();
98 if (token < 0) {
99 if (token != -ERESTARTSYS)
100 dev_err(dev, "%s: Couldn't get OPAL async token\n",
101 __func__);
102 return token;
103 }
104
105 rc = opal_leds_set_ind(token, powernv_led->loc_code,
106 led_mask, led_value, &max_type);
107 if (rc != OPAL_ASYNC_COMPLETION) {
108 dev_err(dev, "%s: OPAL set LED call failed for %s [rc=%d]\n",
109 __func__, powernv_led->loc_code, rc);
110 goto out_token;
111 }
112
113 rc = opal_async_wait_response(token, &msg);
114 if (rc) {
115 dev_err(dev,
116 "%s: Failed to wait for the async response [rc=%d]\n",
117 __func__, rc);
118 goto out_token;
119 }
120
121 rc = opal_get_async_rc(msg);
122 if (rc != OPAL_SUCCESS)
123 dev_err(dev, "%s : OAPL async call returned failed [rc=%d]\n",
124 __func__, rc);
125
126out_token:
127 opal_async_release_token(token);
128 return rc;
129}
130
131/*
132 * This function fetches the LED state for a given LED type for
133 * mentioned LED classdev structure.
134 */
135static enum led_brightness powernv_led_get(struct powernv_led_data *powernv_led)
136{
137 int rc;
138 __be64 mask, value, max_type;
139 u64 led_mask, led_value;
140 struct device *dev = powernv_led->cdev.dev;
141 struct powernv_led_common *powernv_led_common = powernv_led->common;
142
143 /* Fetch all LED status */
144 mask = cpu_to_be64(0);
145 value = cpu_to_be64(0);
146 max_type = powernv_led_common->max_led_type;
147
148 rc = opal_leds_get_ind(powernv_led->loc_code,
149 &mask, &value, &max_type);
150 if (rc != OPAL_SUCCESS && rc != OPAL_PARTIAL) {
151 dev_err(dev, "%s: OPAL get led call failed [rc=%d]\n",
152 __func__, rc);
153 return LED_OFF;
154 }
155
156 led_mask = be64_to_cpu(mask);
157 led_value = be64_to_cpu(value);
158
159 /* LED status available */
160 if (!((led_mask >> powernv_led->led_type) & OPAL_SLOT_LED_STATE_ON)) {
161 dev_err(dev, "%s: LED status not available for %s\n",
162 __func__, powernv_led->cdev.name);
163 return LED_OFF;
164 }
165
166 /* LED status value */
167 if ((led_value >> powernv_led->led_type) & OPAL_SLOT_LED_STATE_ON)
168 return LED_FULL;
169
170 return LED_OFF;
171}
172
173/*
174 * LED classdev 'brightness_get' function. This schedules work
175 * to update LED state.
176 */
177static int powernv_brightness_set(struct led_classdev *led_cdev,
178 enum led_brightness value)
179{
180 struct powernv_led_data *powernv_led =
181 container_of(led_cdev, struct powernv_led_data, cdev);
182 struct powernv_led_common *powernv_led_common = powernv_led->common;
183 int rc;
184
185 /* Do not modify LED in unload path */
186 if (powernv_led_common->led_disabled)
187 return 0;
188
189 mutex_lock(&powernv_led_common->lock);
190 rc = powernv_led_set(powernv_led, value);
191 mutex_unlock(&powernv_led_common->lock);
192
193 return rc;
194}
195
196/* LED classdev 'brightness_get' function */
197static enum led_brightness powernv_brightness_get(struct led_classdev *led_cdev)
198{
199 struct powernv_led_data *powernv_led =
200 container_of(led_cdev, struct powernv_led_data, cdev);
201
202 return powernv_led_get(powernv_led);
203}
204
205/*
206 * This function registers classdev structure for any given type of LED on
207 * a given child LED device node.
208 */
209static int powernv_led_create(struct device *dev,
210 struct powernv_led_data *powernv_led,
211 const char *led_type_desc)
212{
213 int rc;
214
215 /* Make sure LED type is supported */
216 powernv_led->led_type = powernv_get_led_type(led_type_desc);
217 if (powernv_led->led_type == -1) {
218 dev_warn(dev, "%s: No support for led type : %s\n",
219 __func__, led_type_desc);
220 return -EINVAL;
221 }
222
223 /* Create the name for classdev */
224 powernv_led->cdev.name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s",
225 powernv_led->loc_code,
226 led_type_desc);
227 if (!powernv_led->cdev.name) {
228 dev_err(dev,
229 "%s: Memory allocation failed for classdev name\n",
230 __func__);
231 return -ENOMEM;
232 }
233
234 powernv_led->cdev.brightness_set_blocking = powernv_brightness_set;
235 powernv_led->cdev.brightness_get = powernv_brightness_get;
236 powernv_led->cdev.brightness = LED_OFF;
237 powernv_led->cdev.max_brightness = LED_FULL;
238
239 /* Register the classdev */
240 rc = devm_led_classdev_register(dev, &powernv_led->cdev);
241 if (rc) {
242 dev_err(dev, "%s: Classdev registration failed for %s\n",
243 __func__, powernv_led->cdev.name);
244 }
245
246 return rc;
247}
248
249/* Go through LED device tree node and register LED classdev structure */
250static int powernv_led_classdev(struct platform_device *pdev,
251 struct device_node *led_node,
252 struct powernv_led_common *powernv_led_common)
253{
254 const char *cur = NULL;
255 int rc = -1;
256 struct property *p;
257 struct device_node *np;
258 struct powernv_led_data *powernv_led;
259 struct device *dev = &pdev->dev;
260
261 for_each_child_of_node(led_node, np) {
262 p = of_find_property(np, "led-types", NULL);
263
264 while ((cur = of_prop_next_string(p, cur)) != NULL) {
265 powernv_led = devm_kzalloc(dev, sizeof(*powernv_led),
266 GFP_KERNEL);
267 if (!powernv_led) {
268 of_node_put(np);
269 return -ENOMEM;
270 }
271
272 powernv_led->common = powernv_led_common;
273 powernv_led->loc_code = (char *)np->name;
274
275 rc = powernv_led_create(dev, powernv_led, cur);
276 if (rc) {
277 of_node_put(np);
278 return rc;
279 }
280 } /* while end */
281 }
282
283 return rc;
284}
285
286/* Platform driver probe */
287static int powernv_led_probe(struct platform_device *pdev)
288{
289 struct device_node *led_node;
290 struct powernv_led_common *powernv_led_common;
291 struct device *dev = &pdev->dev;
292
293 led_node = of_find_node_by_path("/ibm,opal/leds");
294 if (!led_node) {
295 dev_err(dev, "%s: LED parent device node not found\n",
296 __func__);
297 return -EINVAL;
298 }
299
300 powernv_led_common = devm_kzalloc(dev, sizeof(*powernv_led_common),
301 GFP_KERNEL);
302 if (!powernv_led_common)
303 return -ENOMEM;
304
305 mutex_init(&powernv_led_common->lock);
306 powernv_led_common->max_led_type = cpu_to_be64(OPAL_SLOT_LED_TYPE_MAX);
307
308 platform_set_drvdata(pdev, powernv_led_common);
309
310 return powernv_led_classdev(pdev, led_node, powernv_led_common);
311}
312
313/* Platform driver remove */
314static int powernv_led_remove(struct platform_device *pdev)
315{
316 struct powernv_led_common *powernv_led_common;
317
318 /* Disable LED operation */
319 powernv_led_common = platform_get_drvdata(pdev);
320 powernv_led_common->led_disabled = true;
321
322 /* Destroy lock */
323 mutex_destroy(&powernv_led_common->lock);
324
325 dev_info(&pdev->dev, "PowerNV led module unregistered\n");
326 return 0;
327}
328
329/* Platform driver property match */
330static const struct of_device_id powernv_led_match[] = {
331 {
332 .compatible = "ibm,opal-v3-led",
333 },
334 {},
335};
336MODULE_DEVICE_TABLE(of, powernv_led_match);
337
338static struct platform_driver powernv_led_driver = {
339 .probe = powernv_led_probe,
340 .remove = powernv_led_remove,
341 .driver = {
342 .name = "powernv-led-driver",
343 .of_match_table = powernv_led_match,
344 },
345};
346
347module_platform_driver(powernv_led_driver);
348
349MODULE_LICENSE("GPL v2");
350MODULE_DESCRIPTION("PowerNV LED driver");
351MODULE_AUTHOR("Vasant Hegde <hegdevasant@linux.vnet.ibm.com>");