xref: /linux/drivers/base/firmware_loader/sysfs_upload.c (revision 08df80a3c51674ab73ae770885a383ca553fbbbf)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 #include <linux/firmware.h>
4 #include <linux/module.h>
5 #include <linux/slab.h>
6 
7 #include "sysfs_upload.h"
8 
9 /*
10  * Support for user-space to initiate a firmware upload to a device.
11  */
12 
13 static const char * const fw_upload_prog_str[] = {
14 	[FW_UPLOAD_PROG_IDLE]	      = "idle",
15 	[FW_UPLOAD_PROG_RECEIVING]    = "receiving",
16 	[FW_UPLOAD_PROG_PREPARING]    = "preparing",
17 	[FW_UPLOAD_PROG_TRANSFERRING] = "transferring",
18 	[FW_UPLOAD_PROG_PROGRAMMING]  = "programming"
19 };
20 
21 static const char * const fw_upload_err_str[] = {
22 	[FW_UPLOAD_ERR_NONE]	     = "none",
23 	[FW_UPLOAD_ERR_HW_ERROR]     = "hw-error",
24 	[FW_UPLOAD_ERR_TIMEOUT]	     = "timeout",
25 	[FW_UPLOAD_ERR_CANCELED]     = "user-abort",
26 	[FW_UPLOAD_ERR_BUSY]	     = "device-busy",
27 	[FW_UPLOAD_ERR_INVALID_SIZE] = "invalid-file-size",
28 	[FW_UPLOAD_ERR_RW_ERROR]     = "read-write-error",
29 	[FW_UPLOAD_ERR_WEAROUT]	     = "flash-wearout",
30 	[FW_UPLOAD_ERR_FW_INVALID]   = "firmware-invalid",
31 };
32 
33 static const char *fw_upload_progress(struct device *dev,
34 				      enum fw_upload_prog prog)
35 {
36 	const char *status = "unknown-status";
37 
38 	if (prog < FW_UPLOAD_PROG_MAX)
39 		status = fw_upload_prog_str[prog];
40 	else
41 		dev_err(dev, "Invalid status during secure update: %d\n", prog);
42 
43 	return status;
44 }
45 
46 static const char *fw_upload_error(struct device *dev,
47 				   enum fw_upload_err err_code)
48 {
49 	const char *error = "unknown-error";
50 
51 	if (err_code < FW_UPLOAD_ERR_MAX)
52 		error = fw_upload_err_str[err_code];
53 	else
54 		dev_err(dev, "Invalid error code during secure update: %d\n",
55 			err_code);
56 
57 	return error;
58 }
59 
60 static ssize_t
61 status_show(struct device *dev, struct device_attribute *attr, char *buf)
62 {
63 	struct fw_upload_priv *fwlp = to_fw_sysfs(dev)->fw_upload_priv;
64 
65 	return sysfs_emit(buf, "%s\n", fw_upload_progress(dev, fwlp->progress));
66 }
67 DEVICE_ATTR_RO(status);
68 
69 static ssize_t
70 error_show(struct device *dev, struct device_attribute *attr, char *buf)
71 {
72 	struct fw_upload_priv *fwlp = to_fw_sysfs(dev)->fw_upload_priv;
73 	int ret;
74 
75 	mutex_lock(&fwlp->lock);
76 
77 	if (fwlp->progress != FW_UPLOAD_PROG_IDLE)
78 		ret = -EBUSY;
79 	else if (!fwlp->err_code)
80 		ret = 0;
81 	else
82 		ret = sysfs_emit(buf, "%s:%s\n",
83 				 fw_upload_progress(dev, fwlp->err_progress),
84 				 fw_upload_error(dev, fwlp->err_code));
85 
86 	mutex_unlock(&fwlp->lock);
87 
88 	return ret;
89 }
90 DEVICE_ATTR_RO(error);
91 
92 static ssize_t cancel_store(struct device *dev, struct device_attribute *attr,
93 			    const char *buf, size_t count)
94 {
95 	struct fw_upload_priv *fwlp = to_fw_sysfs(dev)->fw_upload_priv;
96 	int ret = count;
97 	bool cancel;
98 
99 	if (kstrtobool(buf, &cancel) || !cancel)
100 		return -EINVAL;
101 
102 	mutex_lock(&fwlp->lock);
103 	if (fwlp->progress == FW_UPLOAD_PROG_IDLE)
104 		ret = -ENODEV;
105 
106 	fwlp->ops->cancel(fwlp->fw_upload);
107 	mutex_unlock(&fwlp->lock);
108 
109 	return ret;
110 }
111 DEVICE_ATTR_WO(cancel);
112 
113 static ssize_t remaining_size_show(struct device *dev,
114 				   struct device_attribute *attr, char *buf)
115 {
116 	struct fw_upload_priv *fwlp = to_fw_sysfs(dev)->fw_upload_priv;
117 
118 	return sysfs_emit(buf, "%u\n", fwlp->remaining_size);
119 }
120 DEVICE_ATTR_RO(remaining_size);
121 
122 umode_t
123 fw_upload_is_visible(struct kobject *kobj, struct attribute *attr, int n)
124 {
125 	static struct fw_sysfs *fw_sysfs;
126 
127 	fw_sysfs = to_fw_sysfs(kobj_to_dev(kobj));
128 
129 	if (fw_sysfs->fw_upload_priv || attr == &dev_attr_loading.attr)
130 		return attr->mode;
131 
132 	return 0;
133 }
134 
135 static void fw_upload_update_progress(struct fw_upload_priv *fwlp,
136 				      enum fw_upload_prog new_progress)
137 {
138 	mutex_lock(&fwlp->lock);
139 	fwlp->progress = new_progress;
140 	mutex_unlock(&fwlp->lock);
141 }
142 
143 static void fw_upload_set_error(struct fw_upload_priv *fwlp,
144 				enum fw_upload_err err_code)
145 {
146 	mutex_lock(&fwlp->lock);
147 	fwlp->err_progress = fwlp->progress;
148 	fwlp->err_code = err_code;
149 	mutex_unlock(&fwlp->lock);
150 }
151 
152 static void fw_upload_prog_complete(struct fw_upload_priv *fwlp)
153 {
154 	mutex_lock(&fwlp->lock);
155 	fwlp->progress = FW_UPLOAD_PROG_IDLE;
156 	mutex_unlock(&fwlp->lock);
157 }
158 
159 static void fw_upload_main(struct work_struct *work)
160 {
161 	struct fw_upload_priv *fwlp;
162 	struct fw_sysfs *fw_sysfs;
163 	u32 written = 0, offset = 0;
164 	enum fw_upload_err ret;
165 	struct device *fw_dev;
166 	struct fw_upload *fwl;
167 
168 	fwlp = container_of(work, struct fw_upload_priv, work);
169 	fwl = fwlp->fw_upload;
170 	fw_sysfs = (struct fw_sysfs *)fwl->priv;
171 	fw_dev = &fw_sysfs->dev;
172 
173 	fw_upload_update_progress(fwlp, FW_UPLOAD_PROG_PREPARING);
174 	ret = fwlp->ops->prepare(fwl, fwlp->data, fwlp->remaining_size);
175 	if (ret != FW_UPLOAD_ERR_NONE) {
176 		fw_upload_set_error(fwlp, ret);
177 		goto putdev_exit;
178 	}
179 
180 	fw_upload_update_progress(fwlp, FW_UPLOAD_PROG_TRANSFERRING);
181 	while (fwlp->remaining_size) {
182 		ret = fwlp->ops->write(fwl, fwlp->data, offset,
183 					fwlp->remaining_size, &written);
184 		if (ret != FW_UPLOAD_ERR_NONE || !written) {
185 			if (ret == FW_UPLOAD_ERR_NONE) {
186 				dev_warn(fw_dev, "write-op wrote zero data\n");
187 				ret = FW_UPLOAD_ERR_RW_ERROR;
188 			}
189 			fw_upload_set_error(fwlp, ret);
190 			goto done;
191 		}
192 
193 		fwlp->remaining_size -= written;
194 		offset += written;
195 	}
196 
197 	fw_upload_update_progress(fwlp, FW_UPLOAD_PROG_PROGRAMMING);
198 	ret = fwlp->ops->poll_complete(fwl);
199 	if (ret != FW_UPLOAD_ERR_NONE)
200 		fw_upload_set_error(fwlp, ret);
201 
202 done:
203 	if (fwlp->ops->cleanup)
204 		fwlp->ops->cleanup(fwl);
205 
206 putdev_exit:
207 	put_device(fw_dev->parent);
208 
209 	/*
210 	 * Note: fwlp->remaining_size is left unmodified here to provide
211 	 * additional information on errors. It will be reinitialized when
212 	 * the next firmeware upload begins.
213 	 */
214 	mutex_lock(&fw_lock);
215 	fw_free_paged_buf(fw_sysfs->fw_priv);
216 	fw_state_init(fw_sysfs->fw_priv);
217 	mutex_unlock(&fw_lock);
218 	fwlp->data = NULL;
219 	fw_upload_prog_complete(fwlp);
220 }
221 
222 /*
223  * Start a worker thread to upload data to the parent driver.
224  * Must be called with fw_lock held.
225  */
226 int fw_upload_start(struct fw_sysfs *fw_sysfs)
227 {
228 	struct fw_priv *fw_priv = fw_sysfs->fw_priv;
229 	struct device *fw_dev = &fw_sysfs->dev;
230 	struct fw_upload_priv *fwlp;
231 
232 	if (!fw_sysfs->fw_upload_priv)
233 		return 0;
234 
235 	if (!fw_priv->size) {
236 		fw_free_paged_buf(fw_priv);
237 		fw_state_init(fw_sysfs->fw_priv);
238 		return 0;
239 	}
240 
241 	fwlp = fw_sysfs->fw_upload_priv;
242 	mutex_lock(&fwlp->lock);
243 
244 	/* Do not interfere with an on-going fw_upload */
245 	if (fwlp->progress != FW_UPLOAD_PROG_IDLE) {
246 		mutex_unlock(&fwlp->lock);
247 		return -EBUSY;
248 	}
249 
250 	get_device(fw_dev->parent); /* released in fw_upload_main */
251 
252 	fwlp->progress = FW_UPLOAD_PROG_RECEIVING;
253 	fwlp->err_code = 0;
254 	fwlp->remaining_size = fw_priv->size;
255 	fwlp->data = fw_priv->data;
256 
257 	pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
258 		 __func__, fw_priv->fw_name,
259 		 fw_priv, fw_priv->data,
260 		 (unsigned int)fw_priv->size);
261 
262 	queue_work(system_long_wq, &fwlp->work);
263 	mutex_unlock(&fwlp->lock);
264 
265 	return 0;
266 }
267 
268 void fw_upload_free(struct fw_sysfs *fw_sysfs)
269 {
270 	struct fw_upload_priv *fw_upload_priv = fw_sysfs->fw_upload_priv;
271 
272 	free_fw_priv(fw_sysfs->fw_priv);
273 	kfree(fw_upload_priv->fw_upload);
274 	kfree(fw_upload_priv);
275 }
276 
277 /**
278  * firmware_upload_register() - register for the firmware upload sysfs API
279  * @module: kernel module of this device
280  * @parent: parent device instantiating firmware upload
281  * @name: firmware name to be associated with this device
282  * @ops: pointer to structure of firmware upload ops
283  * @dd_handle: pointer to parent driver private data
284  *
285  *	@name must be unique among all users of firmware upload. The firmware
286  *	sysfs files for this device will be found at /sys/class/firmware/@name.
287  *
288  *	Return: struct fw_upload pointer or ERR_PTR()
289  *
290  **/
291 struct fw_upload *
292 firmware_upload_register(struct module *module, struct device *parent,
293 			 const char *name, const struct fw_upload_ops *ops,
294 			 void *dd_handle)
295 {
296 	u32 opt_flags = FW_OPT_NOCACHE;
297 	struct fw_upload *fw_upload;
298 	struct fw_upload_priv *fw_upload_priv;
299 	struct fw_sysfs *fw_sysfs;
300 	struct fw_priv *fw_priv;
301 	struct device *fw_dev;
302 	int ret;
303 
304 	if (!name || name[0] == '\0')
305 		return ERR_PTR(-EINVAL);
306 
307 	if (!ops || !ops->cancel || !ops->prepare ||
308 	    !ops->write || !ops->poll_complete) {
309 		dev_err(parent, "Attempt to register without all required ops\n");
310 		return ERR_PTR(-EINVAL);
311 	}
312 
313 	if (!try_module_get(module))
314 		return ERR_PTR(-EFAULT);
315 
316 	fw_upload = kzalloc(sizeof(*fw_upload), GFP_KERNEL);
317 	if (!fw_upload) {
318 		ret = -ENOMEM;
319 		goto exit_module_put;
320 	}
321 
322 	fw_upload_priv = kzalloc(sizeof(*fw_upload_priv), GFP_KERNEL);
323 	if (!fw_upload_priv) {
324 		ret = -ENOMEM;
325 		goto free_fw_upload;
326 	}
327 
328 	fw_upload_priv->fw_upload = fw_upload;
329 	fw_upload_priv->ops = ops;
330 	mutex_init(&fw_upload_priv->lock);
331 	fw_upload_priv->module = module;
332 	fw_upload_priv->name = name;
333 	fw_upload_priv->err_code = 0;
334 	fw_upload_priv->progress = FW_UPLOAD_PROG_IDLE;
335 	INIT_WORK(&fw_upload_priv->work, fw_upload_main);
336 	fw_upload->dd_handle = dd_handle;
337 
338 	fw_sysfs = fw_create_instance(NULL, name, parent, opt_flags);
339 	if (IS_ERR(fw_sysfs)) {
340 		ret = PTR_ERR(fw_sysfs);
341 		goto free_fw_upload_priv;
342 	}
343 	fw_upload->priv = fw_sysfs;
344 	fw_sysfs->fw_upload_priv = fw_upload_priv;
345 	fw_dev = &fw_sysfs->dev;
346 
347 	ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv,  NULL, 0, 0,
348 				   FW_OPT_NOCACHE);
349 	if (ret != 0) {
350 		if (ret > 0)
351 			ret = -EINVAL;
352 		goto free_fw_sysfs;
353 	}
354 	fw_priv->is_paged_buf = true;
355 	fw_sysfs->fw_priv = fw_priv;
356 
357 	ret = device_add(fw_dev);
358 	if (ret) {
359 		dev_err(fw_dev, "%s: device_register failed\n", __func__);
360 		put_device(fw_dev);
361 		goto exit_module_put;
362 	}
363 
364 	return fw_upload;
365 
366 free_fw_sysfs:
367 	kfree(fw_sysfs);
368 
369 free_fw_upload_priv:
370 	kfree(fw_upload_priv);
371 
372 free_fw_upload:
373 	kfree(fw_upload);
374 
375 exit_module_put:
376 	module_put(module);
377 
378 	return ERR_PTR(ret);
379 }
380 EXPORT_SYMBOL_GPL(firmware_upload_register);
381 
382 /**
383  * firmware_upload_unregister() - Unregister firmware upload interface
384  * @fw_upload: pointer to struct fw_upload
385  **/
386 void firmware_upload_unregister(struct fw_upload *fw_upload)
387 {
388 	struct fw_sysfs *fw_sysfs = fw_upload->priv;
389 	struct fw_upload_priv *fw_upload_priv = fw_sysfs->fw_upload_priv;
390 	struct module *module = fw_upload_priv->module;
391 
392 	mutex_lock(&fw_upload_priv->lock);
393 	if (fw_upload_priv->progress == FW_UPLOAD_PROG_IDLE) {
394 		mutex_unlock(&fw_upload_priv->lock);
395 		goto unregister;
396 	}
397 
398 	fw_upload_priv->ops->cancel(fw_upload);
399 	mutex_unlock(&fw_upload_priv->lock);
400 
401 	/* Ensure lower-level device-driver is finished */
402 	flush_work(&fw_upload_priv->work);
403 
404 unregister:
405 	device_unregister(&fw_sysfs->dev);
406 	module_put(module);
407 }
408 EXPORT_SYMBOL_GPL(firmware_upload_unregister);
409