lib: qmi: Introduce QMI Encode/Decode library
Introduce Encode/Decode Library to perform QMI message marshaling.
The QMI Encode/Decode Library encodes the kernel C data structures into
QMI wire format and decodes the messages in QMI wire format into kernel
C structures.
Change-Id: Ib443e697dafedeac8a790de9a3a8ed4a8444082f
Signed-off-by: Karthikeyan Ramasubramanian <kramasub@codeaurora.org>
diff --git a/include/linux/qmi_encdec.h b/include/linux/qmi_encdec.h
new file mode 100644
index 0000000..4c5f6d3
--- /dev/null
+++ b/include/linux/qmi_encdec.h
@@ -0,0 +1,169 @@
+/* Copyright (c) 2012, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _QMI_ENCDEC_H_
+#define _QMI_ENCDEC_H_
+
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/list.h>
+#include <linux/socket.h>
+#include <linux/gfp.h>
+
+#define QMI_REQUEST_CONTROL_FLAG 0x00
+#define QMI_RESPONSE_CONTROL_FLAG 0x02
+#define QMI_INDICATION_CONTROL_FLAG 0x04
+#define QMI_HEADER_SIZE 7
+
+/**
+ * elem_type - Enum to identify the data type of elements in a data
+ * structure.
+ */
+enum elem_type {
+ QMI_OPT_FLAG = 1,
+ QMI_DATA_LEN,
+ QMI_UNSIGNED_1_BYTE,
+ QMI_UNSIGNED_2_BYTE,
+ QMI_UNSIGNED_4_BYTE,
+ QMI_UNSIGNED_8_BYTE,
+ QMI_SIGNED_2_BYTE_ENUM,
+ QMI_SIGNED_4_BYTE_ENUM,
+ QMI_STRUCT,
+ QMI_EOTI,
+};
+
+/**
+ * array_type - Enum to identify if an element in a data structure is
+ * an array. If so, then is it a static length array or a
+ * variable length array.
+ */
+enum array_type {
+ NO_ARRAY = 0,
+ STATIC_ARRAY = 1,
+ VAR_LEN_ARRAY = 2,
+};
+
+/**
+ * elem_info - Data structure to specify information about an element
+ * in a data structure. An array of this data structure
+ * can be used to specify info about a complex data
+ * structure to be encoded/decoded.
+ *
+ * @data_type: Data type of this element.
+ * @elem_len: Array length of this element, if an array.
+ * @elem_size: Size of a single instance of this data type.
+ * @is_array: Array type of this element.
+ * @tlv_type: QMI message specific type to identify which element
+ * is present in an incoming message.
+ * @offset: To identify the address of the first instance of this
+ * element in the data structure.
+ * @ei_array: Array to provide information about the nested structure
+ * within a data structure to be encoded/decoded.
+ */
+struct elem_info {
+ enum elem_type data_type;
+ uint32_t elem_len;
+ uint32_t elem_size;
+ enum array_type is_array;
+ uint8_t tlv_type;
+ uint32_t offset;
+ struct elem_info *ei_array;
+};
+
+/**
+ * @msg_desc - Describe about the main/outer structure to be
+ * encoded/decoded.
+ *
+ * @max_msg_len: Maximum possible length of the QMI message.
+ * @ei_array: Array to provide information about a data structure.
+ */
+struct msg_desc {
+ uint16_t msg_id;
+ int max_msg_len;
+ struct elem_info *ei_array;
+};
+
+struct qmi_header {
+ unsigned char cntl_flag;
+ uint16_t txn_id;
+ uint16_t msg_id;
+ uint16_t msg_len;
+} __attribute__((__packed__));
+
+static inline void encode_qmi_header(unsigned char *buf,
+ unsigned char cntl_flag, uint16_t txn_id,
+ uint16_t msg_id, uint16_t msg_len)
+{
+ struct qmi_header *hdr = (struct qmi_header *)buf;
+
+ hdr->cntl_flag = cntl_flag;
+ hdr->txn_id = txn_id;
+ hdr->msg_id = msg_id;
+ hdr->msg_len = msg_len;
+}
+
+static inline void decode_qmi_header(unsigned char *buf,
+ unsigned char *cntl_flag, uint16_t *txn_id,
+ uint16_t *msg_id, uint16_t *msg_len)
+{
+ struct qmi_header *hdr = (struct qmi_header *)buf;
+
+ *cntl_flag = hdr->cntl_flag;
+ *txn_id = hdr->txn_id;
+ *msg_id = hdr->msg_id;
+ *msg_len = hdr->msg_len;
+}
+
+#ifdef CONFIG_QMI_ENCDEC
+/**
+ * qmi_kernel_encode() - Encode to QMI message wire format
+ * @desc: Pointer to structure descriptor.
+ * @out_buf: Buffer to hold the encoded QMI message.
+ * @out_buf_len: Length of the out buffer.
+ * @in_c_struct: C Structure to be encoded.
+ *
+ * @return: size of encoded message on success, < 0 on error.
+ */
+int qmi_kernel_encode(struct msg_desc *desc,
+ void *out_buf, uint32_t out_buf_len,
+ void *in_c_struct);
+
+/**
+ * qmi_kernel_decode() - Decode to C Structure format
+ * @desc: Pointer to structure descriptor.
+ * @out_c_struct: Buffer to hold the decoded C structure.
+ * @in_buf: Buffer containg the QMI message to be decoded.
+ * @in_buf_len: Length of the incoming QMI message.
+ *
+ * @return: 0 on success, < 0 on error.
+ */
+int qmi_kernel_decode(struct msg_desc *desc, void *out_c_struct,
+ void *in_buf, uint32_t in_buf_len);
+
+#else
+static inline int qmi_kernel_encode(struct msg_desc *desc,
+ void *out_buf, uint32_t out_buf_len,
+ void *in_c_struct)
+{
+ return -EOPNOTSUPP;
+}
+
+static inline int qmi_kernel_decode(struct msg_desc *desc,
+ void *out_c_struct,
+ void *in_buf, uint32_t in_buf_len)
+{
+ return -EOPNOTSUPP;
+}
+#endif
+
+#endif
diff --git a/lib/Kconfig b/lib/Kconfig
index 4a8aba2..f1621d5 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -378,4 +378,13 @@
Digital signature verification. Currently only RSA is supported.
Implementation is done using GnuPG MPI library
+config QMI_ENCDEC
+ bool
+ help
+ Library to encode & decode QMI messages from within
+ the kernel. The kernel drivers encode the C structure into
+ QMI message wire format and then send it over a transport.
+ The kernel drivers receive the QMI message over a transport
+ and then decode it into a C structure.
+
endmenu
diff --git a/lib/Makefile b/lib/Makefile
index acd6869..0fbcb04 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -123,6 +123,8 @@
obj-$(CONFIG_CLZ_TAB) += clz_tab.o
+obj-$(CONFIG_QMI_ENCDEC) += qmi_encdec.o
+
hostprogs-y := gen_crc32table
clean-files := crc32table.h
diff --git a/lib/qmi_encdec.c b/lib/qmi_encdec.c
new file mode 100644
index 0000000..d759885
--- /dev/null
+++ b/lib/qmi_encdec.c
@@ -0,0 +1,492 @@
+/* Copyright (c) 2012, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/string.h>
+#include <linux/qmi_encdec.h>
+
+#include "qmi_encdec_priv.h"
+
+#define TLV_LEN_SIZE sizeof(uint16_t)
+#define TLV_TYPE_SIZE sizeof(uint8_t)
+
+static int _qmi_kernel_encode(struct elem_info *ei_array,
+ void *out_buf, void *in_c_struct,
+ int enc_level);
+
+static int _qmi_kernel_decode(struct elem_info *ei_array,
+ void *out_c_struct,
+ void *in_buf, uint32_t in_buf_len,
+ int dec_level);
+
+/**
+ * qmi_kernel_encode() - Encode to QMI message wire format
+ * @desc: Pointer to structure descriptor.
+ * @out_buf: Buffer to hold the encoded QMI message.
+ * @out_buf_len: Length of the out buffer.
+ * @in_c_struct: C Structure to be encoded.
+ *
+ * @return: size of encoded message on success, < 0 for error.
+ */
+int qmi_kernel_encode(struct msg_desc *desc,
+ void *out_buf, uint32_t out_buf_len,
+ void *in_c_struct)
+{
+ int enc_level = 1;
+
+ if (!desc || !desc->ei_array)
+ return -EINVAL;
+
+ if (!out_buf || !in_c_struct)
+ return -EINVAL;
+
+ if (desc->max_msg_len < out_buf_len)
+ return -ETOOSMALL;
+
+ return _qmi_kernel_encode(desc->ei_array, out_buf,
+ in_c_struct, enc_level);
+}
+EXPORT_SYMBOL(qmi_kernel_encode);
+
+/**
+ * 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.
+ *
+ * @return: number of bytes of encoded information.
+ *
+ * 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 uint8_t - uint64_t or similar. This
+ * function returns the number of bytes of encoded information.
+ */
+static int qmi_encode_basic_elem(void *buf_dst, void *buf_src,
+ uint32_t elem_len, uint32_t elem_size)
+{
+ uint32_t 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.
+ * @enc_level: Depth of the nested structure from the main structure.
+ *
+ * @return: Mumber of bytes of encoded information, on success.
+ * < 0 on error.
+ *
+ * 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.
+ */
+static int qmi_encode_struct_elem(struct elem_info *ei_array,
+ void *buf_dst, void *buf_src,
+ uint32_t elem_len, int enc_level)
+{
+ int i, rc, encoded_bytes = 0;
+ struct elem_info *temp_ei = ei_array;
+
+ for (i = 0; i < elem_len; i++) {
+ rc = _qmi_kernel_encode(temp_ei->ei_array,
+ buf_dst, buf_src, 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;
+}
+
+/**
+ * skip_to_next_elem() - Skip to next element in the structure to be encoded
+ * @ei_array: Struct info describing the element to be skipped.
+ *
+ * @return: Struct info of the next element that can be encoded.
+ *
+ * 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.
+ */
+static struct elem_info *skip_to_next_elem(struct elem_info *ei_array)
+{
+ struct elem_info *temp_ei = ei_array;
+ uint8_t tlv_type;
+
+ do {
+ tlv_type = temp_ei->tlv_type;
+ temp_ei = temp_ei + 1;
+ } while (tlv_type == temp_ei->tlv_type);
+
+ return temp_ei;
+}
+
+/**
+ * _qmi_kernel_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.
+ * @enc_level: Encode level to indicate the depth of the nested structure,
+ * within the main structure, being encoded.
+ *
+ * @return: Number of bytes of encoded information, on success.
+ * < 0 on error.
+ */
+static int _qmi_kernel_encode(struct elem_info *ei_array,
+ void *out_buf, void *in_c_struct,
+ int enc_level)
+{
+ struct elem_info *temp_ei = ei_array;
+ uint8_t opt_flag_value = 0;
+ uint32_t data_len_value = 0, data_len_sz;
+ uint8_t *buf_dst = (uint8_t *)out_buf;
+ uint8_t *tlv_pointer;
+ uint32_t tlv_len;
+ uint8_t tlv_type;
+ uint32_t encoded_bytes = 0;
+ void *buf_src;
+ int encode_tlv = 0;
+ int rc;
+
+ tlv_pointer = buf_dst;
+ tlv_len = 0;
+ 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->is_array == NO_ARRAY) {
+ data_len_value = 1;
+ } else if (temp_ei->is_array == 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(uint8_t));
+ if (opt_flag_value)
+ temp_ei = temp_ei + 1;
+ else
+ temp_ei = skip_to_next_elem(temp_ei);
+ break;
+
+ case QMI_DATA_LEN:
+ memcpy(&data_len_value, buf_src, temp_ei->elem_size);
+ data_len_sz = temp_ei->elem_size == sizeof(uint8_t) ?
+ sizeof(uint8_t) : sizeof(uint16_t);
+ rc = qmi_encode_basic_elem(buf_dst, &data_len_value,
+ 1, data_len_sz);
+ if (data_len_value) {
+ UPDATE_ENCODE_VARIABLES(temp_ei, buf_dst,
+ encoded_bytes, tlv_len, encode_tlv, rc);
+ encode_tlv = 0;
+ } else {
+ temp_ei = skip_to_next_elem(temp_ei);
+ }
+ 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:
+ 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, (enc_level + 1));
+ 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_kernel_decode() - Decode to C Structure format
+ * @desc: Pointer to structure descriptor.
+ * @out_c_struct: Buffer to hold the decoded C structure.
+ * @in_buf: Buffer containg the QMI message to be decoded.
+ * @in_buf_len: Length of the incoming QMI message.
+ *
+ * @return: 0 on success, < 0 on error.
+ */
+int qmi_kernel_decode(struct msg_desc *desc, void *out_c_struct,
+ void *in_buf, uint32_t in_buf_len)
+{
+ int dec_level = 1;
+ int rc = 0;
+
+ if (!desc || !desc->ei_array)
+ return -EINVAL;
+
+ if (!out_c_struct || !in_buf || !in_buf_len)
+ return -EINVAL;
+
+ if (desc->max_msg_len < in_buf_len)
+ return -EINVAL;
+
+ rc = _qmi_kernel_decode(desc->ei_array, out_c_struct,
+ in_buf, in_buf_len, dec_level);
+ if (rc < 0)
+ return rc;
+ else
+ return 0;
+}
+EXPORT_SYMBOL(qmi_kernel_decode);
+
+/**
+ * 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.
+ *
+ * @return: Total size of the decoded data elements, in bytes.
+ *
+ * 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 uint8_t - uint64_t or similar. This
+ * function returns the number of bytes of decoded information.
+ */
+static int qmi_decode_basic_elem(void *buf_dst, void *buf_src,
+ uint32_t elem_len, uint32_t elem_size)
+{
+ uint32_t 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.
+ *
+ * @return: Total size of the decoded data elements, on success.
+ * < 0 on error.
+ *
+ * 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.
+ */
+static int qmi_decode_struct_elem(struct elem_info *ei_array, void *buf_dst,
+ void *buf_src, uint32_t elem_len,
+ uint32_t tlv_len, int dec_level)
+{
+ int i, rc, decoded_bytes = 0;
+ struct elem_info *temp_ei = ei_array;
+
+ for (i = 0; i < elem_len; i++) {
+ rc = _qmi_kernel_decode(temp_ei->ei_array, buf_dst, buf_src,
+ (tlv_len/elem_len), dec_level);
+ if (rc < 0)
+ return rc;
+ if (rc != (tlv_len/elem_len)) {
+ pr_err("%s: Fault in decoding\n", __func__);
+ return -EFAULT;
+ }
+ buf_src = buf_src + rc;
+ buf_dst = buf_dst + temp_ei->elem_size;
+ 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.
+ *
+ * @return: Pointer to struct info, if found
+ *
+ * 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.
+ */
+static struct elem_info *find_ei(struct elem_info *ei_array,
+ uint32_t type)
+{
+ struct elem_info *temp_ei = ei_array;
+ while (temp_ei->data_type != QMI_EOTI) {
+ if (temp_ei->tlv_type == (uint8_t)type)
+ return temp_ei;
+ temp_ei = temp_ei + 1;
+ }
+ return NULL;
+}
+
+/**
+ * _qmi_kernel_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: Number of bytes of decoded information, on success
+ * < 0 on error.
+ */
+static int _qmi_kernel_decode(struct elem_info *ei_array,
+ void *out_c_struct,
+ void *in_buf, uint32_t in_buf_len,
+ int dec_level)
+{
+ struct elem_info *temp_ei = ei_array;
+ uint8_t opt_flag_value = 1;
+ uint32_t data_len_value = 0, data_len_sz = 0;
+ uint8_t *buf_dst = out_c_struct;
+ uint8_t *tlv_pointer;
+ uint32_t tlv_len = 0;
+ uint32_t tlv_type;
+ uint32_t decoded_bytes = 0;
+ void *buf_src = in_buf;
+ int rc;
+
+ while (decoded_bytes < in_buf_len) {
+ 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) {
+ pr_err("%s: Inval element info\n", __func__);
+ return -EINVAL;
+ }
+ }
+
+ buf_dst = out_c_struct + temp_ei->offset;
+ if (temp_ei->data_type == QMI_OPT_FLAG) {
+ memcpy(buf_dst, &opt_flag_value, sizeof(uint8_t));
+ 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(uint8_t) ?
+ sizeof(uint8_t) : sizeof(uint16_t);
+ rc = qmi_decode_basic_elem(&data_len_value, buf_src,
+ 1, data_len_sz);
+ memcpy(buf_dst, &data_len_value, sizeof(uint32_t));
+ temp_ei = temp_ei + 1;
+ buf_dst = out_c_struct + temp_ei->offset;
+ UPDATE_DECODE_VARIABLES(buf_src, decoded_bytes, rc);
+ }
+
+ if (temp_ei->is_array == NO_ARRAY) {
+ data_len_value = 1;
+ } else if (temp_ei->is_array == 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;
+ default:
+ pr_err("%s: Unrecognized data type\n", __func__);
+ return -EINVAL;
+ }
+ temp_ei = temp_ei + 1;
+ }
+ return decoded_bytes;
+}
+MODULE_DESCRIPTION("QMI kernel enc/dec");
+MODULE_LICENSE("GPL v2");
diff --git a/lib/qmi_encdec_priv.h b/lib/qmi_encdec_priv.h
new file mode 100644
index 0000000..97fe45b
--- /dev/null
+++ b/lib/qmi_encdec_priv.h
@@ -0,0 +1,66 @@
+/* Copyright (c) 2012, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _QMI_ENCDEC_PRIV_H_
+#define _QMI_ENCDEC_PRIV_H_
+
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/list.h>
+#include <linux/socket.h>
+#include <linux/gfp.h>
+#include <linux/qmi_encdec.h>
+
+#define QMI_ENCDEC_ENCODE_TLV(type, length, p_dst) do { \
+ *p_dst++ = type; \
+ *p_dst++ = ((uint8_t)((length) & 0xFF)); \
+ *p_dst++ = ((uint8_t)(((length) >> 8) & 0xFF)); \
+} while (0)
+
+#define QMI_ENCDEC_DECODE_TLV(p_type, p_length, p_src) do { \
+ *p_type = (uint8_t)*p_src++; \
+ *p_length = (uint8_t)*p_src++; \
+ *p_length |= ((uint8_t)*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 = (uint8_t *)p_dst + size; \
+ p_src = (uint8_t *)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 = (uint8_t *)p_dst + size; \
+ p_src = (uint8_t *)p_src + size; \
+} while (0)
+
+#define UPDATE_ENCODE_VARIABLES(temp_si, buf_dst, \
+ encoded_bytes, tlv_len, encode_tlv, rc) \
+do { \
+ buf_dst = (uint8_t *)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 = (uint8_t *)buf_src + rc; \
+ decoded_bytes += rc; \
+} while (0)
+
+#endif