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v6.9.4
  1/*
  2 * Copyright 2019 Advanced Micro Devices, Inc.
  3 *
  4 * Permission is hereby granted, free of charge, to any person obtaining a
  5 * copy of this software and associated documentation files (the "Software"),
  6 * to deal in the Software without restriction, including without limitation
  7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  8 * and/or sell copies of the Software, and to permit persons to whom the
  9 * Software is furnished to do so, subject to the following conditions:
 10 *
 11 * The above copyright notice and this permission notice shall be included in
 12 * all copies or substantial portions of the Software.
 13 *
 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 20 * OTHER DEALINGS IN THE SOFTWARE.
 21 *
 22 */
 23#include <linux/pci.h>
 24
 25#include "amdgpu.h"
 26#include "amdgpu_i2c.h"
 27#include "smu_v11_0_i2c.h"
 28#include "atom.h"
 29#include "amdgpu_fru_eeprom.h"
 30#include "amdgpu_eeprom.h"
 31
 32#define FRU_EEPROM_MADDR_6      0x60000
 33#define FRU_EEPROM_MADDR_8      0x80000
 
 34
 35static bool is_fru_eeprom_supported(struct amdgpu_device *adev, u32 *fru_addr)
 36{
 37	/* Only server cards have the FRU EEPROM
 38	 * TODO: See if we can figure this out dynamically instead of
 39	 * having to parse VBIOS versions.
 40	 */
 41	struct atom_context *atom_ctx = adev->mode_info.atom_context;
 42
 43	/* The i2c access is blocked on VF
 44	 * TODO: Need other way to get the info
 45	 * Also, FRU not valid for APU devices.
 46	 */
 47	if (amdgpu_sriov_vf(adev) || (adev->flags & AMD_IS_APU))
 48		return false;
 49
 50	/* The default I2C EEPROM address of the FRU.
 51	 */
 52	if (fru_addr)
 53		*fru_addr = FRU_EEPROM_MADDR_8;
 54
 55	/* VBIOS is of the format ###-DXXXYYYY-##. For SKU identification,
 56	 * we can use just the "DXXX" portion. If there were more models, we
 57	 * could convert the 3 characters to a hex integer and use a switch
 58	 * for ease/speed/readability. For now, 2 string comparisons are
 59	 * reasonable and not too expensive
 60	 */
 61	switch (amdgpu_ip_version(adev, MP1_HWIP, 0)) {
 62	case IP_VERSION(11, 0, 2):
 63		switch (adev->asic_type) {
 64		case CHIP_VEGA20:
 65			/* D161 and D163 are the VG20 server SKUs */
 66			if (strnstr(atom_ctx->vbios_pn, "D161",
 67				    sizeof(atom_ctx->vbios_pn)) ||
 68			    strnstr(atom_ctx->vbios_pn, "D163",
 69				    sizeof(atom_ctx->vbios_pn))) {
 70				if (fru_addr)
 71					*fru_addr = FRU_EEPROM_MADDR_6;
 72				return true;
 73			} else {
 74				return false;
 75			}
 76		case CHIP_ARCTURUS:
 77		default:
 78			return false;
 79		}
 80	case IP_VERSION(11, 0, 7):
 81		if (strnstr(atom_ctx->vbios_pn, "D603",
 82			    sizeof(atom_ctx->vbios_pn))) {
 83			if (strnstr(atom_ctx->vbios_pn, "D603GLXE",
 84				    sizeof(atom_ctx->vbios_pn))) {
 85				return false;
 86			}
 87
 88			if (fru_addr)
 89				*fru_addr = FRU_EEPROM_MADDR_6;
 90			return true;
 91
 92		} else {
 93			return false;
 94		}
 95	case IP_VERSION(13, 0, 2):
 96		/* All Aldebaran SKUs have an FRU */
 97		if (!strnstr(atom_ctx->vbios_pn, "D673",
 98			     sizeof(atom_ctx->vbios_pn)))
 99			if (fru_addr)
100				*fru_addr = FRU_EEPROM_MADDR_6;
101		return true;
102	case IP_VERSION(13, 0, 6):
103			if (fru_addr)
104				*fru_addr = FRU_EEPROM_MADDR_8;
105			return true;
106	default:
107		return false;
108	}
109}
110
111int amdgpu_fru_get_product_info(struct amdgpu_device *adev)
 
112{
113	struct amdgpu_fru_info *fru_info;
114	unsigned char buf[8], *pia;
115	u32 addr, fru_addr;
116	int size, len;
117	u8 csum;
118
119	if (!is_fru_eeprom_supported(adev, &fru_addr))
120		return 0;
 
 
121
122	if (!adev->fru_info) {
123		adev->fru_info = kzalloc(sizeof(*adev->fru_info), GFP_KERNEL);
124		if (!adev->fru_info)
125			return -ENOMEM;
126	}
127
128	fru_info = adev->fru_info;
129	/* For Arcturus-and-later, default value of serial_number is unique_id
130	 * so convert it to a 16-digit HEX string for convenience and
131	 * backwards-compatibility.
132	 */
133	sprintf(fru_info->serial, "%llx", adev->unique_id);
 
 
134
135	/* If algo exists, it means that the i2c_adapter's initialized */
136	if (!adev->pm.fru_eeprom_i2c_bus || !adev->pm.fru_eeprom_i2c_bus->algo) {
137		DRM_WARN("Cannot access FRU, EEPROM accessor not initialized");
138		return -ENODEV;
139	}
140
141	/* Read the IPMI Common header */
142	len = amdgpu_eeprom_read(adev->pm.fru_eeprom_i2c_bus, fru_addr, buf,
143				 sizeof(buf));
144	if (len != 8) {
145		DRM_ERROR("Couldn't read the IPMI Common Header: %d", len);
146		return len < 0 ? len : -EIO;
147	}
148
149	if (buf[0] != 1) {
150		DRM_ERROR("Bad IPMI Common Header version: 0x%02x", buf[0]);
151		return -EIO;
152	}
153
154	for (csum = 0; len > 0; len--)
155		csum += buf[len - 1];
156	if (csum) {
157		DRM_ERROR("Bad IPMI Common Header checksum: 0x%02x", csum);
158		return -EIO;
159	}
160
161	/* Get the offset to the Product Info Area (PIA). */
162	addr = buf[4] * 8;
163	if (!addr)
164		return 0;
165
166	/* Get the absolute address to the PIA. */
167	addr += fru_addr;
168
169	/* Read the header of the PIA. */
170	len = amdgpu_eeprom_read(adev->pm.fru_eeprom_i2c_bus, addr, buf, 3);
171	if (len != 3) {
172		DRM_ERROR("Couldn't read the Product Info Area header: %d", len);
173		return len < 0 ? len : -EIO;
174	}
175
176	if (buf[0] != 1) {
177		DRM_ERROR("Bad IPMI Product Info Area version: 0x%02x", buf[0]);
178		return -EIO;
179	}
180
181	size = buf[1] * 8;
182	pia = kzalloc(size, GFP_KERNEL);
183	if (!pia)
184		return -ENOMEM;
 
 
185
186	/* Read the whole PIA. */
187	len = amdgpu_eeprom_read(adev->pm.fru_eeprom_i2c_bus, addr, pia, size);
188	if (len != size) {
189		kfree(pia);
190		DRM_ERROR("Couldn't read the Product Info Area: %d", len);
191		return len < 0 ? len : -EIO;
 
 
 
 
192	}
193
194	for (csum = 0; size > 0; size--)
195		csum += pia[size - 1];
196	if (csum) {
197		DRM_ERROR("Bad Product Info Area checksum: 0x%02x", csum);
198		kfree(pia);
199		return -EIO;
 
 
200	}
201
202	/* Now extract useful information from the PIA.
203	 *
204	 * Read Manufacturer Name field whose length is [3].
205	 */
206	addr = 3;
207	if (addr + 1 >= len)
208		goto Out;
209	memcpy(fru_info->manufacturer_name, pia + addr + 1,
210	       min_t(size_t, sizeof(fru_info->manufacturer_name),
211		     pia[addr] & 0x3F));
212	fru_info->manufacturer_name[sizeof(fru_info->manufacturer_name) - 1] =
213		'\0';
214
215	/* Read Product Name field. */
216	addr += 1 + (pia[addr] & 0x3F);
217	if (addr + 1 >= len)
218		goto Out;
219	memcpy(fru_info->product_name, pia + addr + 1,
220	       min_t(size_t, sizeof(fru_info->product_name), pia[addr] & 0x3F));
221	fru_info->product_name[sizeof(fru_info->product_name) - 1] = '\0';
222
223	/* Go to the Product Part/Model Number field. */
224	addr += 1 + (pia[addr] & 0x3F);
225	if (addr + 1 >= len)
226		goto Out;
227	memcpy(fru_info->product_number, pia + addr + 1,
228	       min_t(size_t, sizeof(fru_info->product_number),
229		     pia[addr] & 0x3F));
230	fru_info->product_number[sizeof(fru_info->product_number) - 1] = '\0';
231
232	/* Go to the Product Version field. */
233	addr += 1 + (pia[addr] & 0x3F);
234
235	/* Go to the Product Serial Number field. */
236	addr += 1 + (pia[addr] & 0x3F);
237	if (addr + 1 >= len)
238		goto Out;
239	memcpy(fru_info->serial, pia + addr + 1,
240	       min_t(size_t, sizeof(fru_info->serial), pia[addr] & 0x3F));
241	fru_info->serial[sizeof(fru_info->serial) - 1] = '\0';
242
243	/* Asset Tag field */
244	addr += 1 + (pia[addr] & 0x3F);
245
246	/* FRU File Id field. This could be 'null'. */
247	addr += 1 + (pia[addr] & 0x3F);
248	if ((addr + 1 >= len) || !(pia[addr] & 0x3F))
249		goto Out;
250	memcpy(fru_info->fru_id, pia + addr + 1,
251	       min_t(size_t, sizeof(fru_info->fru_id), pia[addr] & 0x3F));
252	fru_info->fru_id[sizeof(fru_info->fru_id) - 1] = '\0';
253
254Out:
255	kfree(pia);
256	return 0;
257}
258
259/**
260 * DOC: product_name
261 *
262 * The amdgpu driver provides a sysfs API for reporting the product name
263 * for the device
264 * The file product_name is used for this and returns the product name
265 * as returned from the FRU.
266 * NOTE: This is only available for certain server cards
267 */
268
269static ssize_t amdgpu_fru_product_name_show(struct device *dev,
270					    struct device_attribute *attr,
271					    char *buf)
272{
273	struct drm_device *ddev = dev_get_drvdata(dev);
274	struct amdgpu_device *adev = drm_to_adev(ddev);
275
276	return sysfs_emit(buf, "%s\n", adev->fru_info->product_name);
277}
278
279static DEVICE_ATTR(product_name, 0444, amdgpu_fru_product_name_show, NULL);
280
281/**
282 * DOC: product_number
283 *
284 * The amdgpu driver provides a sysfs API for reporting the part number
285 * for the device
286 * The file product_number is used for this and returns the part number
287 * as returned from the FRU.
288 * NOTE: This is only available for certain server cards
289 */
290
291static ssize_t amdgpu_fru_product_number_show(struct device *dev,
292					      struct device_attribute *attr,
293					      char *buf)
294{
295	struct drm_device *ddev = dev_get_drvdata(dev);
296	struct amdgpu_device *adev = drm_to_adev(ddev);
297
298	return sysfs_emit(buf, "%s\n", adev->fru_info->product_number);
299}
300
301static DEVICE_ATTR(product_number, 0444, amdgpu_fru_product_number_show, NULL);
302
303/**
304 * DOC: serial_number
305 *
306 * The amdgpu driver provides a sysfs API for reporting the serial number
307 * for the device
308 * The file serial_number is used for this and returns the serial number
309 * as returned from the FRU.
310 * NOTE: This is only available for certain server cards
311 */
312
313static ssize_t amdgpu_fru_serial_number_show(struct device *dev,
314					     struct device_attribute *attr,
315					     char *buf)
316{
317	struct drm_device *ddev = dev_get_drvdata(dev);
318	struct amdgpu_device *adev = drm_to_adev(ddev);
319
320	return sysfs_emit(buf, "%s\n", adev->fru_info->serial);
321}
322
323static DEVICE_ATTR(serial_number, 0444, amdgpu_fru_serial_number_show, NULL);
324
325/**
326 * DOC: fru_id
327 *
328 * The amdgpu driver provides a sysfs API for reporting FRU File Id
329 * for the device.
330 * The file fru_id is used for this and returns the File Id value
331 * as returned from the FRU.
332 * NOTE: This is only available for certain server cards
333 */
334
335static ssize_t amdgpu_fru_id_show(struct device *dev,
336				  struct device_attribute *attr, char *buf)
337{
338	struct drm_device *ddev = dev_get_drvdata(dev);
339	struct amdgpu_device *adev = drm_to_adev(ddev);
340
341	return sysfs_emit(buf, "%s\n", adev->fru_info->fru_id);
342}
343
344static DEVICE_ATTR(fru_id, 0444, amdgpu_fru_id_show, NULL);
 
 
 
 
 
345
346/**
347 * DOC: manufacturer
348 *
349 * The amdgpu driver provides a sysfs API for reporting manufacturer name from
350 * FRU information.
351 * The file manufacturer returns the value as returned from the FRU.
352 * NOTE: This is only available for certain server cards
353 */
354
355static ssize_t amdgpu_fru_manufacturer_name_show(struct device *dev,
356						 struct device_attribute *attr,
357						 char *buf)
358{
359	struct drm_device *ddev = dev_get_drvdata(dev);
360	struct amdgpu_device *adev = drm_to_adev(ddev);
361
362	return sysfs_emit(buf, "%s\n", adev->fru_info->manufacturer_name);
363}
364
365static DEVICE_ATTR(manufacturer, 0444, amdgpu_fru_manufacturer_name_show, NULL);
 
 
 
366
367static const struct attribute *amdgpu_fru_attributes[] = {
368	&dev_attr_product_name.attr,
369	&dev_attr_product_number.attr,
370	&dev_attr_serial_number.attr,
371	&dev_attr_fru_id.attr,
372	&dev_attr_manufacturer.attr,
373	NULL
374};
375
376int amdgpu_fru_sysfs_init(struct amdgpu_device *adev)
377{
378	if (!is_fru_eeprom_supported(adev, NULL) || !adev->fru_info)
379		return 0;
380
381	return sysfs_create_files(&adev->dev->kobj, amdgpu_fru_attributes);
382}
383
384void amdgpu_fru_sysfs_fini(struct amdgpu_device *adev)
385{
386	if (!is_fru_eeprom_supported(adev, NULL) || !adev->fru_info)
387		return;
 
 
 
 
 
 
388
389	sysfs_remove_files(&adev->dev->kobj, amdgpu_fru_attributes);
390}
v5.14.15
  1/*
  2 * Copyright 2019 Advanced Micro Devices, Inc.
  3 *
  4 * Permission is hereby granted, free of charge, to any person obtaining a
  5 * copy of this software and associated documentation files (the "Software"),
  6 * to deal in the Software without restriction, including without limitation
  7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  8 * and/or sell copies of the Software, and to permit persons to whom the
  9 * Software is furnished to do so, subject to the following conditions:
 10 *
 11 * The above copyright notice and this permission notice shall be included in
 12 * all copies or substantial portions of the Software.
 13 *
 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 20 * OTHER DEALINGS IN THE SOFTWARE.
 21 *
 22 */
 23#include <linux/pci.h>
 24
 25#include "amdgpu.h"
 26#include "amdgpu_i2c.h"
 27#include "smu_v11_0_i2c.h"
 28#include "atom.h"
 29#include "amdgpu_fru_eeprom.h"
 
 30
 31#define I2C_PRODUCT_INFO_ADDR		0xAC
 32#define I2C_PRODUCT_INFO_ADDR_SIZE	0x2
 33#define I2C_PRODUCT_INFO_OFFSET		0xC0
 34
 35static bool is_fru_eeprom_supported(struct amdgpu_device *adev)
 36{
 37	/* Only server cards have the FRU EEPROM
 38	 * TODO: See if we can figure this out dynamically instead of
 39	 * having to parse VBIOS versions.
 40	 */
 41	struct atom_context *atom_ctx = adev->mode_info.atom_context;
 42
 43	/* VBIOS is of the format ###-DXXXYY-##. For SKU identification,
 
 
 
 
 
 
 
 
 
 
 
 
 44	 * we can use just the "DXXX" portion. If there were more models, we
 45	 * could convert the 3 characters to a hex integer and use a switch
 46	 * for ease/speed/readability. For now, 2 string comparisons are
 47	 * reasonable and not too expensive
 48	 */
 49	switch (adev->asic_type) {
 50	case CHIP_VEGA20:
 51		/* D161 and D163 are the VG20 server SKUs */
 52		if (strnstr(atom_ctx->vbios_version, "D161",
 53			    sizeof(atom_ctx->vbios_version)) ||
 54		    strnstr(atom_ctx->vbios_version, "D163",
 55			    sizeof(atom_ctx->vbios_version)))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 56			return true;
 57		else
 
 58			return false;
 
 
 
 
 
 
 
 
 
 
 
 
 59	default:
 60		return false;
 61	}
 62}
 63
 64static int amdgpu_fru_read_eeprom(struct amdgpu_device *adev, uint32_t addrptr,
 65			   unsigned char *buff)
 66{
 67	int ret, size;
 68	struct i2c_msg msg = {
 69			.addr   = I2C_PRODUCT_INFO_ADDR,
 70			.flags  = I2C_M_RD,
 71			.buf    = buff,
 72	};
 73	buff[0] = 0;
 74	buff[1] = addrptr;
 75	msg.len = I2C_PRODUCT_INFO_ADDR_SIZE + 1;
 76	ret = i2c_transfer(&adev->pm.smu_i2c, &msg, 1);
 77
 78	if (ret < 1) {
 79		DRM_WARN("FRU: Failed to get size field");
 80		return ret;
 
 81	}
 82
 83	/* The size returned by the i2c requires subtraction of 0xC0 since the
 84	 * size apparently always reports as 0xC0+actual size.
 
 
 85	 */
 86	size = buff[2] - I2C_PRODUCT_INFO_OFFSET;
 87	/* Add 1 since address field was 1 byte */
 88	buff[1] = addrptr + 1;
 89
 90	msg.len = I2C_PRODUCT_INFO_ADDR_SIZE + size;
 91	ret = i2c_transfer(&adev->pm.smu_i2c, &msg, 1);
 
 
 
 92
 93	if (ret < 1) {
 94		DRM_WARN("FRU: Failed to get data field");
 95		return ret;
 
 
 
 96	}
 97
 98	return size;
 99}
 
 
100
101int amdgpu_fru_get_product_info(struct amdgpu_device *adev)
102{
103	unsigned char buff[34];
104	int addrptr, size;
105	int len;
 
106
107	if (!is_fru_eeprom_supported(adev))
 
 
108		return 0;
109
110	/* If algo exists, it means that the i2c_adapter's initialized */
111	if (!adev->pm.smu_i2c.algo) {
112		DRM_WARN("Cannot access FRU, EEPROM accessor not initialized");
113		return -ENODEV;
 
 
 
 
 
 
 
 
 
114	}
115
116	/* There's a lot of repetition here. This is due to the FRU having
117	 * variable-length fields. To get the information, we have to find the
118	 * size of each field, and then keep reading along and reading along
119	 * until we get all of the data that we want. We use addrptr to track
120	 * the address as we go
121	 */
122
123	/* The first fields are all of size 1-byte, from 0-7 are offsets that
124	 * contain information that isn't useful to us.
125	 * Bytes 8-a are all 1-byte and refer to the size of the entire struct,
126	 * and the language field, so just start from 0xb, manufacturer size
127	 */
128	addrptr = 0xb;
129	size = amdgpu_fru_read_eeprom(adev, addrptr, buff);
130	if (size < 1) {
131		DRM_ERROR("Failed to read FRU Manufacturer, ret:%d", size);
132		return -EINVAL;
133	}
134
135	/* Increment the addrptr by the size of the field, and 1 due to the
136	 * size field being 1 byte. This pattern continues below.
137	 */
138	addrptr += size + 1;
139	size = amdgpu_fru_read_eeprom(adev, addrptr, buff);
140	if (size < 1) {
141		DRM_ERROR("Failed to read FRU product name, ret:%d", size);
142		return -EINVAL;
143	}
144
145	len = size;
146	/* Product name should only be 32 characters. Any more,
147	 * and something could be wrong. Cap it at 32 to be safe
148	 */
149	if (len >= sizeof(adev->product_name)) {
150		DRM_WARN("FRU Product Number is larger than 32 characters. This is likely a mistake");
151		len = sizeof(adev->product_name) - 1;
152	}
153	/* Start at 2 due to buff using fields 0 and 1 for the address */
154	memcpy(adev->product_name, &buff[2], len);
155	adev->product_name[len] = '\0';
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
156
157	addrptr += size + 1;
158	size = amdgpu_fru_read_eeprom(adev, addrptr, buff);
159	if (size < 1) {
160		DRM_ERROR("Failed to read FRU product number, ret:%d", size);
161		return -EINVAL;
162	}
163
164	len = size;
165	/* Product number should only be 16 characters. Any more,
166	 * and something could be wrong. Cap it at 16 to be safe
167	 */
168	if (len >= sizeof(adev->product_number)) {
169		DRM_WARN("FRU Product Number is larger than 16 characters. This is likely a mistake");
170		len = sizeof(adev->product_number) - 1;
171	}
172	memcpy(adev->product_number, &buff[2], len);
173	adev->product_number[len] = '\0';
 
 
 
 
 
174
175	addrptr += size + 1;
176	size = amdgpu_fru_read_eeprom(adev, addrptr, buff);
177
178	if (size < 1) {
179		DRM_ERROR("Failed to read FRU product version, ret:%d", size);
180		return -EINVAL;
181	}
182
183	addrptr += size + 1;
184	size = amdgpu_fru_read_eeprom(adev, addrptr, buff);
 
 
 
 
 
 
185
186	if (size < 1) {
187		DRM_ERROR("Failed to read FRU serial number, ret:%d", size);
188		return -EINVAL;
189	}
 
 
 
190
191	len = size;
192	/* Serial number should only be 16 characters. Any more,
193	 * and something could be wrong. Cap it at 16 to be safe
194	 */
195	if (len >= sizeof(adev->serial)) {
196		DRM_WARN("FRU Serial Number is larger than 16 characters. This is likely a mistake");
197		len = sizeof(adev->serial) - 1;
198	}
199	memcpy(adev->serial, &buff[2], len);
200	adev->serial[len] = '\0';
201
202	return 0;
203}