// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2012-2015, The Linux Foundation. All rights reserved.
* Copyright (C) 2017 Linaro Ltd.
*/
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/soc/qcom/qmi.h>
#define QMI_ENCDEC_ENCODE_TLV(type, length, p_dst) do { \
*p_dst++ = type; \
*p_dst++ = ((u8)((length) & 0xFF)); \
*p_dst++ = ((u8)(((length) >> 8) & 0xFF)); \
} while (0)
#define QMI_ENCDEC_DECODE_TLV(p_type, p_length, p_src) do { \
*p_type = (u8)*p_src++; \
*p_length = (u8)*p_src++; \
*p_length |= ((u8)*p_src) << 8; \
} while (0)
#define QMI_ENCDEC_ENCODE_N_BYTES(p_dst, p_src, size) \
do { \
memcpy(p_dst, p_src, size); \
p_dst = (u8 *)p_dst + size; \
p_src = (u8 *)p_src + size; \
} while (0)
#define QMI_ENCDEC_DECODE_N_BYTES(p_dst, p_src, size) \
do { \
memcpy(p_dst, p_src, size); \
p_dst = (u8 *)p_dst + size; \
p_src = (u8 *)p_src + size; \
} while (0)
#define UPDATE_ENCODE_VARIABLES(temp_si, buf_dst, \
encoded_bytes, tlv_len, encode_tlv, rc) \
do { \
buf_dst = (u8 *)buf_dst + rc; \
encoded_bytes += rc; \
tlv_len += rc; \
temp_si = temp_si + 1; \
encode_tlv = 1; \
} while (0)
#define UPDATE_DECODE_VARIABLES(buf_src, decoded_bytes, rc) \
do { \
buf_src = (u8 *)buf_src + rc; \
decoded_bytes += rc; \
} while (0)
#define TLV_LEN_SIZE sizeof(u16)
#define TLV_TYPE_SIZE sizeof(u8)
#define OPTIONAL_TLV_TYPE_START 0x10
static int qmi_encode(struct qmi_elem_info *ei_array, void *out_buf,
const void *in_c_struct, u32 out_buf_len,
int enc_level);
static int qmi_decode(struct qmi_elem_info *ei_array, void *out_c_struct,
const void *in_buf, u32 in_buf_len, int dec_level);
/**
* skip_to_next_elem() - Skip to next element in the structure to be encoded
* @ei_array: Struct info describing the element to be skipped.
* @level: Depth level of encoding/decoding to identify nested structures.
*
* This function is used while encoding optional elements. If the flag
* corresponding to an optional element is not set, then encoding the
* optional element can be skipped. This function can be used to perform
* that operation.
*
* Return: struct info of the next element that can be encoded.
*/
static struct qmi_elem_info *skip_to_next_elem(struct qmi_elem_info *ei_array,
int level)
{
struct qmi_elem_info *temp_ei = ei_array;
u8 tlv_type;
if (level > 1) {
temp_ei = temp_ei + 1;
} else {
do {
tlv_type = temp_ei->tlv_type;
temp_ei = temp_ei + 1;
} while (tlv_type == temp_ei->tlv_type);
}
return temp_ei;
}
/**
* qmi_calc_min_msg_len() - Calculate the minimum length of a QMI message
* @ei_array: Struct info array describing the structure.
* @level: Level to identify the depth of the nested structures.
*
* Return: Expected minimum length of the QMI message or 0 on error.
*/
static int qmi_calc_min_msg_len(struct qmi_elem_info *ei_array,
int level)
{
int min_msg_len = 0;
struct qmi_elem_info *temp_ei = ei_array;
if (!ei_array)
return min_msg_len;
while (temp_ei->data_type != QMI_EOTI) {
/* Optional elements do not count in minimum length */
if (temp_ei->data_type == QMI_OPT_FLAG) {
temp_ei = skip_to_next_elem(temp_ei, level);
continue;
}
if (temp_ei->data_type == QMI_DATA_LEN) {
min_msg_len += (temp_ei->elem_size == sizeof(u8) ?
sizeof(u8) : sizeof(u16));
temp_ei++;
continue;
} else if (temp_ei->data_type == QMI_STRUCT) {
min_msg_len += qmi_calc_min_msg_len(temp_ei->ei_array,
(level + 1));
temp_ei++;
} else if (temp_ei->data_type == QMI_STRING) {
if (level > 1)
min_msg_len += temp_ei->elem_len <= U8_MAX ?
sizeof(u8) : sizeof(u16);
min_msg_len += temp_ei->elem_len * temp_ei->elem_size;
temp_ei++;
} else {
min_msg_len += (temp_ei->elem_len * temp_ei->elem_size);
temp_ei++;
}
/*
* Type & Length info. not prepended for elements in the
* nested structure.
*/
if (level == 1)
min_msg_len += (TLV_TYPE_SIZE + TLV_LEN_SIZE);
}
return min_msg_len;
}
/**
* qmi_encode_basic_elem() - Encodes elements of basic/primary data type
* @buf_dst: Buffer to store the encoded information.
* @buf_src: Buffer containing the elements to be encoded.
* @elem_len: Number of elements, in the buf_src, to be encoded.
* @elem_size: Size of a single instance of the element to be encoded.
*
* This function encodes the "elem_len" number of data elements, each of
* size "elem_size" bytes from the source buffer "buf_src" and stores the
* encoded information in the destination buffer "buf_dst". The elements are
* of primary data type which include u8 - u64 or similar. This
* function returns the number of bytes of encoded information.
*
* Return: The number of bytes of encoded information.
*/
static int qmi_encode_basic_elem(void *buf_dst, const void *buf_src,
u32 elem_len, u32 elem_size)
{
u32 i, rc = 0;
for (i = 0; i < elem_len; i++) {
QMI_ENCDEC_ENCODE_N_BYTES(buf_dst, buf_src, elem_size);
rc += elem_size;
}
return rc;
}
/**
* qmi_encode_struct_elem() - Encodes elements of struct data type
* @ei_array: Struct info array descibing the struct element.
* @buf_dst: Buffer to store the encoded information.
* @buf_src: Buffer containing the elements to be encoded.
* @elem_len: Number of elements, in the buf_src, to be encoded.
* @out_buf_len: Available space in the encode buffer.
* @enc_level: Depth of the nested structure from the main structure.
*
* This function encodes the "elem_len" number of struct elements, each of
* size "ei_array->elem_size" bytes from the source buffer "buf_src" and
* stores the encoded information in the destination buffer "buf_dst". The
* elements are of struct data type which includes any C structure. This
* function returns the number of bytes of encoded information.
*
* Return: The number of bytes of encoded information on success or negative
* errno on error.
*/
static int qmi_encode_struct_elem(struct qmi_elem_info *ei_array,
void *buf_dst, const void *buf_src,
u32 elem_len, u32 out_buf_len,
int enc_level)
{
int i, rc, encoded_bytes = 0;
struct qmi_elem_info *temp_ei = ei_array;
for (i = 0; i < elem_len; i++) {
rc = qmi_encode(temp_ei->ei_array, buf_dst, buf_src,
out_buf_len - encoded_bytes, enc_level);
if (rc < 0) {
pr_err("%s: STRUCT Encode failure\n", __func__);
return rc;
}
buf_dst = buf_dst + rc;
buf_src = buf_src + temp_ei->elem_size;
encoded_bytes += rc;
}
return encoded_bytes;
}
/**
* qmi_encode_string_elem() - Encodes elements of string data type
* @ei_array: Struct info array descibing the string element.
* @buf_dst: Buffer to store the encoded information.
* @buf_src: Buffer containing the elements to be encoded.
* @out_buf_len: Available space in the encode buffer.
* @enc_level: Depth of the string element from the main structure.
*
* This function encodes a string element of maximum length "ei_array->elem_len"
* bytes from the source buffer "buf_src" and stores the encoded information in
* the destination buffer "buf_dst". This function returns the number of bytes
* of encoded information.
*
* Return: The number of bytes of encoded information on success or negative
* errno on error.
*/
static int qmi_encode_string_elem(struct qmi_elem_info *ei_array,
void *buf_dst, const void *buf_src,
u32 out_buf_len, int enc_level)
{
int rc;
int encoded_bytes = 0;
struct qmi_elem_info *temp_ei = ei_array;
u32 string_len = 0;
u32 string_len_sz = 0;
string_len = strlen(buf_src);
string_len_sz = temp_ei->elem_len <= U8_MAX ?
sizeof(u8) : sizeof(u16);
if (string_len > temp_ei->elem_len) {
pr_err("%s: String to be encoded is longer - %d > %d\n",
__func__, string_len, temp_ei->elem_len);
return -EINVAL;
}
if (enc_level == 1) {
if (string_len + TLV_LEN_SIZE + TLV_TYPE_SIZE >
out_buf_len) {
pr_err("%s: Output len %d > Out Buf len %d\n",
__func__, string_len, out_buf_len);
return -ETOOSMALL;
}
} else {
if (string_len + string_len_sz > out_buf_len) {
pr_err("%s: Output len %d > Out Buf len %d\n",
__func__, string_len, out_buf_len);
return -ETOOSMALL;
}
rc = qmi_encode_basic_elem(buf_dst, &string_len,
1, string_len_sz);
encoded_bytes += rc;
}
rc = qmi_encode_basic_elem(buf_dst + encoded_bytes, buf_src,
string_len, temp_ei->elem_size);
encoded_bytes += rc;
return encoded_bytes;
}
/**
* qmi_encode() - Core Encode Function
* @ei_array: Struct info array describing the structure to be encoded.
* @out_buf: Buffer to hold the encoded QMI message.
* @in_c_struct: Pointer to the C structure to be encoded.
* @out_buf_len: Available space in the encode buffer.
* @enc_level: Encode level to indicate the depth of the nested structure,
* within the main structure, being encoded.
*
* Return: The number of bytes of encoded information on success or negative
* errno on error.
*/
static int qmi_encode(struct qmi_elem_info *ei_array, void *out_buf,
const void *in_c_struct, u32 out_buf_len,
int enc_level)
{
struct qmi_elem_info *temp_ei = ei_array;
u8 opt_flag_value = 0;
u32 data_len_value = 0, data_len_sz;
u8 *buf_dst = (u8 *)out_buf;
u8 *tlv_pointer;
u32 tlv_len;
u8 tlv_type;
u32 encoded_bytes = 0;
const void *buf_src;
int encode_tlv = 0;
int rc;
if (!ei_array)
return 0;
tlv_pointer = buf_dst;
tlv_len = 0;
if (enc_level == 1)
buf_dst = buf_dst + (TLV_LEN_SIZE + TLV_TYPE_SIZE);
while (temp_ei->data_type != QMI_EOTI) {
buf_src = in_c_struct + temp_ei->offset;
tlv_type = temp_ei->tlv_type;
if (temp_ei->array_type == NO_ARRAY) {
data_len_value = 1;
} else if (temp_ei->array_type == STATIC_ARRAY) {
data_len_value = temp_ei->elem_len;
} else if (data_len_value <= 0 ||
temp_ei->elem_len < data_len_value) {
pr_err("%s: Invalid data length\n", __func__);
return -EINVAL;
}
switch (temp_ei->data_type) {
case QMI_OPT_FLAG:
rc = qmi_encode_basic_elem(&opt_flag_value, buf_src,
1, sizeof(u8));
if (opt_flag_value)
temp_ei = temp_ei + 1;
else
temp_ei = skip_to_next_elem(temp_ei, enc_level);
break;
case QMI_DATA_LEN:
memcpy(&data_len_value, buf_src, temp_ei->elem_size);
data_len_sz = temp_ei->elem_size == sizeof(u8) ?
sizeof(u8) : sizeof(u16);
/* Check to avoid out of range buffer access */
if ((data_len_sz + encoded_bytes + TLV_LEN_SIZE +
TLV_TYPE_SIZE) > out_buf_len) {
pr_err("%s: Too Small Buffer @DATA_LEN\n",
__func__);
return -ETOOSMALL;
}
rc = qmi_encode_basic_elem(buf_dst, &data_len_value,
1, data_len_sz);
UPDATE_ENCODE_VARIABLES(temp_ei, buf_dst,
encoded_bytes, tlv_len,
encode_tlv, rc);
if (!data_len_value)
temp_ei = skip_to_next_elem(temp_ei, enc_level);
else
encode_tlv = 0;
break;
case QMI_UNSIGNED_1_BYTE:
case QMI_UNSIGNED_2_BYTE:
case QMI_UNSIGNED_4_BYTE:
case QMI_UNSIGNED_8_BYTE:
case QMI_SIGNED_2_BYTE_ENUM:
case QMI_SIGNED_4_BYTE_ENUM:
/* Check to avoid out of range buffer access */
if (((data_len_value * temp_ei->elem_size) +
encoded_bytes + TLV_LEN_SIZE + TLV_TYPE_SIZE) >
out_buf_len) {
pr_err("%s: Too Small Buffer @data_type:%d\n",
__func__, temp_ei->data_type);
return -ETOOSMALL;
}
rc = qmi_encode_basic_elem(buf_dst, buf_src,
data_len_value,
temp_ei->elem_size);
UPDATE_ENCODE_VARIABLES(temp_ei, buf_dst,
encoded_bytes, tlv_len,
encode_tlv, rc);
break;
case QMI_STRUCT:
rc = qmi_encode_struct_elem(temp_ei, buf_dst, buf_src,
data_len_value,
out_buf_len - encoded_bytes,
enc_level + 1);
if (rc < 0)
return rc;
UPDATE_ENCODE_VARIABLES(temp_ei, buf_dst,
encoded_bytes, tlv_len,
encode_tlv, rc);
break;
case QMI_STRING:
rc = qmi_encode_string_elem(temp_ei, buf_dst, buf_src,
out_buf_len - encoded_bytes,
enc_level);
if (rc < 0)
return rc;
UPDATE_ENCODE_VARIABLES(temp_ei, buf_dst,
encoded_bytes, tlv_len,
encode_tlv, rc);
break;
default:
pr_err("%s: Unrecognized data type\n", __func__);
return -EINVAL;
}
if (encode_tlv && enc_level == 1) {
QMI_ENCDEC_ENCODE_TLV(tlv_type, tlv_len, tlv_pointer);
encoded_bytes += (TLV_TYPE_SIZE + TLV_LEN_SIZE);
tlv_pointer = buf_dst;
tlv_len = 0;
buf_dst = buf_dst + TLV_LEN_SIZE + TLV_TYPE_SIZE;
encode_tlv = 0;
}
}
return encoded_bytes;
}
/**
* qmi_decode_basic_elem() - Decodes elements of basic/primary data type
* @buf_dst: Buffer to store the decoded element.
* @buf_src: Buffer containing the elements in QMI wire format.
* @elem_len: Number of elements to be decoded.
* @elem_size: Size of a single instance of the element to be decoded.
*
* This function decodes the "elem_len" number of elements in QMI wire format,
* each of size "elem_size" bytes from the source buffer "buf_src" and stores
* the decoded elements in the destination buffer "buf_dst". The elements are
* of primary data type which include u8 - u64 or similar. This
* function returns the number of bytes of decoded information.
*
* Return: The total size of the decoded data elements, in bytes.
*/
static int qmi_decode_basic_elem(void *buf_dst, const void *buf_src,
u32 elem_len, u32 elem_size)
{
u32 i, rc = 0;
for (i = 0; i < elem_len; i++) {
QMI_ENCDEC_DECODE_N_BYTES(buf_dst, buf_src, elem_size);
rc += elem_size;
}
return rc;
}
/**
* qmi_decode_struct_elem() - Decodes elements of struct data type
* @ei_array: Struct info array descibing the struct element.
* @buf_dst: Buffer to store the decoded element.
* @buf_src: Buffer containing the elements in QMI wire format.
* @elem_len: Number of elements to be decoded.
* @tlv_len: Total size of the encoded inforation corresponding to
* this struct element.
* @dec_level: Depth of the nested structure from the main structure.
*
* This function decodes the "elem_len" number of elements in QMI wire format,
* each of size "(tlv_len/elem_len)" bytes from the source buffer "buf_src"
* and stores the decoded elements in the destination buffer "buf_dst". The
* elements are of struct data type which includes any C structure. This
* function returns the number of bytes of decoded information.
*
* Return: The total size of the decoded data elements on success, negative
* errno on error.
*/
static int qmi_decode_struct_elem(struct qmi_elem_info *ei_array,
void *buf_dst, const void *buf_src,
u32 elem_len, u32 tlv_len,
int dec_level)
{
int i, rc, decoded_bytes = 0;
struct qmi_elem_info *temp_ei = ei_array;
for (i = 0; i < elem_len && decoded_bytes < tlv_len; i++) {
rc = qmi_decode(temp_ei->ei_array, buf_dst, buf_src,
tlv_len - decoded_bytes, dec_level);
if (rc < 0)
return rc;
buf_src = buf_src + rc;
buf_dst = buf_dst + temp_ei->elem_size;
decoded_bytes += rc;
}
if ((dec_level <= 2 && decoded_bytes != tlv_len) ||
(dec_level > 2 && (i < elem_len || decoded_bytes > tlv_len))) {
pr_err("%s: Fault in decoding: dl(%d), db(%d), tl(%d), i(%d), el(%d)\n",
__func__, dec_level, decoded_bytes, tlv_len,
i, elem_len);
return -EFAULT;
}
return decoded_bytes;
}
/**
* qmi_decode_string_elem() - Decodes elements of string data type
* @ei_array: Struct info array descibing the string element.
* @buf_dst: Buffer to store the decoded element.
* @buf_src: Buffer containing the elements in QMI wire format.
* @tlv_len: Total size of the encoded inforation corresponding to
* this string element.
* @dec_level: Depth of the string element from the main structure.
*
* This function decodes the string element of maximum length
* "ei_array->elem_len" from the source buffer "buf_src" and puts it into
* the destination buffer "buf_dst". This function returns number of bytes
* decoded from the input buffer.
*
* Return: The total size of the decoded data elements on success, negative
* errno on error.
*/
static int qmi_decode_string_elem(struct qmi_elem_info *ei_array,
void *buf_dst, const void *buf_src,
u32 tlv_len, int dec_level)
{
int rc;
int decoded_bytes = 0;
u32 string_len = 0;
u32 string_len_sz = 0;
struct qmi_elem_info *temp_ei = ei_array;
if (dec_level == 1) {
string_len = tlv_len;
} else {
string_len_sz = temp_ei->elem_len <= U8_MAX ?
sizeof(u8) : sizeof(u16);
rc = qmi_decode_basic_elem(&string_len, buf_src,
1, string_len_sz);
decoded_bytes += rc;
}
if (string_len > temp_ei->elem_len) {
pr_err("%s: String len %d > Max Len %d\n",
__func__, string_len, temp_ei->elem_len);
return -ETOOSMALL;
} else if (string_len > tlv_len) {
pr_err("%s: String len %d > Input Buffer Len %d\n",
__func__, string_len, tlv_len);
return -EFAULT;
}
rc = qmi_decode_basic_elem(buf_dst, buf_src + decoded_bytes,
string_len, temp_ei->elem_size);
*((char *)buf_dst + string_len) = '\0';
decoded_bytes += rc;
return decoded_bytes;
}
/**
* find_ei() - Find element info corresponding to TLV Type
* @ei_array: Struct info array of the message being decoded.
* @type: TLV Type of the element being searched.
*
* Every element that got encoded in the QMI message will have a type
* information associated with it. While decoding the QMI message,
* this function is used to find the struct info regarding the element
* that corresponds to the type being decoded.
*
* Return: Pointer to struct info, if found
*/
static struct qmi_elem_info *find_ei(struct qmi_elem_info *ei_array,
u32 type)
{
struct qmi_elem_info *temp_ei = ei_array;
while (temp_ei->data_type != QMI_EOTI) {
if (temp_ei->tlv_type == (u8)type)
return temp_ei;
temp_ei = temp_ei + 1;
}
return NULL;
}
/**
* qmi_decode() - Core Decode Function
* @ei_array: Struct info array describing the structure to be decoded.
* @out_c_struct: Buffer to hold the decoded C struct
* @in_buf: Buffer containing the QMI message to be decoded
* @in_buf_len: Length of the QMI message to be decoded
* @dec_level: Decode level to indicate the depth of the nested structure,
* within the main structure, being decoded
*
* Return: The number of bytes of decoded information on success, negative
* errno on error.
*/
static int qmi_decode(struct qmi_elem_info *ei_array, void *out_c_struct,
const void *in_buf, u32 in_buf_len,
int dec_level)
{
struct qmi_elem_info *temp_ei = ei_array;
u8 opt_flag_value = 1;
u32 data_len_value = 0, data_len_sz = 0;
u8 *buf_dst = out_c_struct;
const u8 *tlv_pointer;
u32 tlv_len = 0;
u32 tlv_type;
u32 decoded_bytes = 0;
const void *buf_src = in_buf;
int rc;
while (decoded_bytes < in_buf_len) {
if (dec_level >= 2 && temp_ei->data_type == QMI_EOTI)
return decoded_bytes;
if (dec_level == 1) {
tlv_pointer = buf_src;
QMI_ENCDEC_DECODE_TLV(&tlv_type,
&tlv_len, tlv_pointer);
buf_src += (TLV_TYPE_SIZE + TLV_LEN_SIZE);
decoded_bytes += (TLV_TYPE_SIZE + TLV_LEN_SIZE);
temp_ei = find_ei(ei_array, tlv_type);
if (!temp_ei && tlv_type < OPTIONAL_TLV_TYPE_START) {
pr_err("%s: Inval element info\n", __func__);
return -EINVAL;
} else if (!temp_ei) {
UPDATE_DECODE_VARIABLES(buf_src,
decoded_bytes, tlv_len);
continue;
}
} else {
/*
* No length information for elements in nested
* structures. So use remaining decodable buffer space.
*/
tlv_len = in_buf_len - decoded_bytes;
}
buf_dst = out_c_struct + temp_ei->offset;
if (temp_ei->data_type == QMI_OPT_FLAG) {
memcpy(buf_dst, &opt_flag_value, sizeof(u8));
temp_ei = temp_ei + 1;
buf_dst = out_c_struct + temp_ei->offset;
}
if (temp_ei->data_type == QMI_DATA_LEN) {
data_len_sz = temp_ei->elem_size == sizeof(u8) ?
sizeof(u8) : sizeof(u16);
rc = qmi_decode_basic_elem(&data_len_value, buf_src,
1, data_len_sz);
memcpy(buf_dst, &data_len_value, sizeof(u32));
temp_ei = temp_ei + 1;
buf_dst = out_c_struct + temp_ei->offset;
tlv_len -= data_len_sz;
UPDATE_DECODE_VARIABLES(buf_src, decoded_bytes, rc);
}
if (temp_ei->array_type == NO_ARRAY) {
data_len_value = 1;
} else if (temp_ei->array_type == STATIC_ARRAY) {
data_len_value = temp_ei->elem_len;
} else if (data_len_value > temp_ei->elem_len) {
pr_err("%s: Data len %d > max spec %d\n",
__func__, data_len_value, temp_ei->elem_len);
return -ETOOSMALL;
}
switch (temp_ei->data_type) {
case QMI_UNSIGNED_1_BYTE:
case QMI_UNSIGNED_2_BYTE:
case QMI_UNSIGNED_4_BYTE:
case QMI_UNSIGNED_8_BYTE:
case QMI_SIGNED_2_BYTE_ENUM:
case QMI_SIGNED_4_BYTE_ENUM:
rc = qmi_decode_basic_elem(buf_dst, buf_src,
data_len_value,
temp_ei->elem_size);
UPDATE_DECODE_VARIABLES(buf_src, decoded_bytes, rc);
break;
case QMI_STRUCT:
rc = qmi_decode_struct_elem(temp_ei, buf_dst, buf_src,
data_len_value, tlv_len,
dec_level + 1);
if (rc < 0)
return rc;
UPDATE_DECODE_VARIABLES(buf_src, decoded_bytes, rc);
break;
case QMI_STRING:
rc = qmi_decode_string_elem(temp_ei, buf_dst, buf_src,
tlv_len, dec_level);
if (rc < 0)
return rc;
UPDATE_DECODE_VARIABLES(buf_src, decoded_bytes, rc);
break;
default:
pr_err("%s: Unrecognized data type\n", __func__);
return -EINVAL;
}
temp_ei = temp_ei + 1;
}
return decoded_bytes;
}
/**
* qmi_encode_message() - Encode C structure as QMI encoded message
* @type: Type of QMI message
* @msg_id: Message ID of the message
* @len: Passed as max length of the message, updated to actual size
* @txn_id: Transaction ID
* @ei: QMI message descriptor
* @c_struct: Reference to structure to encode
*
* Return: Buffer with encoded message, or negative ERR_PTR() on error
*/
void *qmi_encode_message(int type, unsigned int msg_id, size_t *len,
unsigned int txn_id, struct qmi_elem_info *ei,
const void *c_struct)
{
struct qmi_header *hdr;
ssize_t msglen = 0;
void *msg;
int ret;
/* Check the possibility of a zero length QMI message */
if (!c_struct) {
ret = qmi_calc_min_msg_len(ei, 1);
if (ret) {
pr_err("%s: Calc. len %d != 0, but NULL c_struct\n",
__func__, ret);
return ERR_PTR(-EINVAL);
}
}
msg = kzalloc(sizeof(*hdr) + *len, GFP_KERNEL);
if (!msg)
return ERR_PTR(-ENOMEM);
/* Encode message, if we have a message */
if (c_struct) {
msglen = qmi_encode(ei, msg + sizeof(*hdr), c_struct, *len, 1);
if (msglen < 0) {
kfree(msg);
return ERR_PTR(msglen);
}
}
hdr = msg;
hdr->type = type;
hdr->txn_id = txn_id;
hdr->msg_id = msg_id;
hdr->msg_len = msglen;
*len = sizeof(*hdr) + msglen;
return msg;
}
EXPORT_SYMBOL(qmi_encode_message);
/**
* qmi_decode_message() - Decode QMI encoded message to C structure
* @buf: Buffer with encoded message
* @len: Amount of data in @buf
* @ei: QMI message descriptor
* @c_struct: Reference to structure to decode into
*
* Return: The number of bytes of decoded information on success, negative
* errno on error.
*/
int qmi_decode_message(const void *buf, size_t len,
struct qmi_elem_info *ei, void *c_struct)
{
if (!ei)
return -EINVAL;
if (!c_struct || !buf || !len)
return -EINVAL;
return qmi_decode(ei, c_struct, buf + sizeof(struct qmi_header),
len - sizeof(struct qmi_header), 1);
}
EXPORT_SYMBOL(qmi_decode_message);
/* Common header in all QMI responses */
struct qmi_elem_info qmi_response_type_v01_ei[] = {
{
.data_type = QMI_SIGNED_2_BYTE_ENUM,
.elem_len = 1,
.elem_size = sizeof(u16),
.array_type = NO_ARRAY,
.tlv_type = QMI_COMMON_TLV_TYPE,
.offset = offsetof(struct qmi_response_type_v01, result),
.ei_array = NULL,
},
{
.data_type = QMI_SIGNED_2_BYTE_ENUM,
.elem_len = 1,
.elem_size = sizeof(u16),
.array_type = NO_ARRAY,
.tlv_type = QMI_COMMON_TLV_TYPE,
.offset = offsetof(struct qmi_response_type_v01, error),
.ei_array = NULL,
},
{
.data_type = QMI_EOTI,
.elem_len = 0,
.elem_size = 0,
.array_type = NO_ARRAY,
.tlv_type = QMI_COMMON_TLV_TYPE,
.offset = 0,
.ei_array = NULL,
},
};
EXPORT_SYMBOL(qmi_response_type_v01_ei);
MODULE_DESCRIPTION("QMI encoder/decoder helper");
MODULE_LICENSE("GPL v2");
