648 lines
20 KiB
C
648 lines
20 KiB
C
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/* Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 and
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* only version 2 as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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*/
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#include <linux/slab.h>
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#include <linux/uaccess.h>
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/errno.h>
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#include <linux/io.h>
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#include <linux/string.h>
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#include <linux/qmi_encdec.h>
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#include "qmi_encdec_priv.h"
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#define TLV_LEN_SIZE sizeof(uint16_t)
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#define TLV_TYPE_SIZE sizeof(uint8_t)
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#ifdef CONFIG_QMI_ENCDEC_DEBUG
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#define qmi_encdec_dump(prefix_str, buf, buf_len) do { \
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const u8 *ptr = buf; \
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int i, linelen, remaining = buf_len; \
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int rowsize = 16, groupsize = 1; \
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unsigned char linebuf[256]; \
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for (i = 0; i < buf_len; i += rowsize) { \
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linelen = min(remaining, rowsize); \
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remaining -= linelen; \
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hex_dump_to_buffer(ptr + i, linelen, rowsize, groupsize, \
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linebuf, sizeof(linebuf), false); \
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pr_debug("%s: %s\n", prefix_str, linebuf); \
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} \
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} while (0)
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#define QMI_ENCODE_LOG_MSG(buf, buf_len) do { \
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qmi_encdec_dump("QMI_ENCODE_MSG", buf, buf_len); \
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} while (0)
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#define QMI_DECODE_LOG_MSG(buf, buf_len) do { \
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qmi_encdec_dump("QMI_DECODE_MSG", buf, buf_len); \
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} while (0)
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#define QMI_ENCODE_LOG_ELEM(level, elem_len, elem_size, buf) do { \
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pr_debug("QMI_ENCODE_ELEM lvl: %d, len: %d, size: %d\n", \
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level, elem_len, elem_size); \
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qmi_encdec_dump("QMI_ENCODE_ELEM", buf, (elem_len * elem_size)); \
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} while (0)
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#define QMI_DECODE_LOG_ELEM(level, elem_len, elem_size, buf) do { \
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pr_debug("QMI_DECODE_ELEM lvl: %d, len: %d, size: %d\n", \
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level, elem_len, elem_size); \
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qmi_encdec_dump("QMI_DECODE_ELEM", buf, (elem_len * elem_size)); \
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} while (0)
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#define QMI_ENCODE_LOG_TLV(tlv_type, tlv_len) do { \
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pr_debug("QMI_ENCODE_TLV type: %d, len: %d\n", tlv_type, tlv_len); \
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} while (0)
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#define QMI_DECODE_LOG_TLV(tlv_type, tlv_len) do { \
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pr_debug("QMI_DECODE_TLV type: %d, len: %d\n", tlv_type, tlv_len); \
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} while (0)
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#else
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#define QMI_ENCODE_LOG_MSG(buf, buf_len) { }
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#define QMI_DECODE_LOG_MSG(buf, buf_len) { }
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#define QMI_ENCODE_LOG_ELEM(level, elem_len, elem_size, buf) { }
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#define QMI_DECODE_LOG_ELEM(level, elem_len, elem_size, buf) { }
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#define QMI_ENCODE_LOG_TLV(tlv_type, tlv_len) { }
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#define QMI_DECODE_LOG_TLV(tlv_type, tlv_len) { }
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#endif
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static int _qmi_kernel_encode(struct elem_info *ei_array,
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void *out_buf, void *in_c_struct,
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uint32_t out_buf_len, int enc_level);
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static int _qmi_kernel_decode(struct elem_info *ei_array,
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void *out_c_struct,
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void *in_buf, uint32_t in_buf_len,
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int dec_level);
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/**
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* qmi_calc_max_msg_len() - Calculate the maximum length of a QMI message
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* @ei_array: Struct info array describing the structure.
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* @level: Level to identify the depth of the nested structures.
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*
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* @return: expected maximum length of the QMI message or 0 on failure.
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*/
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static int qmi_calc_max_msg_len(struct elem_info *ei_array,
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int level)
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{
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int max_msg_len = 0;
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struct elem_info *temp_ei;
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if (!ei_array)
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return max_msg_len;
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for (temp_ei = ei_array; temp_ei->data_type != QMI_EOTI; temp_ei++) {
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/* Flag to identify the optional element is not encoded */
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if (temp_ei->data_type == QMI_OPT_FLAG)
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continue;
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if (temp_ei->data_type == QMI_DATA_LEN) {
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max_msg_len += (temp_ei->elem_size == sizeof(uint8_t) ?
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sizeof(uint8_t) : sizeof(uint16_t));
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continue;
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} else if (temp_ei->data_type == QMI_STRUCT) {
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max_msg_len += qmi_calc_max_msg_len(temp_ei->ei_array,
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(level + 1));
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} else {
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max_msg_len += (temp_ei->elem_len * temp_ei->elem_size);
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}
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/*
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* Type & Length info. not prepended for elements in the
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* nested structure.
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*/
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if (level == 1)
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max_msg_len += (TLV_TYPE_SIZE + TLV_LEN_SIZE);
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}
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return max_msg_len;
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}
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/**
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* qmi_verify_max_msg_len() - Verify the maximum length of a QMI message
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* @desc: Pointer to structure descriptor.
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*
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* @return: true if the maximum message length embedded in structure
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* descriptor matches the calculated value, else false.
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*/
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bool qmi_verify_max_msg_len(struct msg_desc *desc)
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{
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int calc_max_msg_len;
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if (!desc)
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return false;
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calc_max_msg_len = qmi_calc_max_msg_len(desc->ei_array, 1);
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if (calc_max_msg_len != desc->max_msg_len) {
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pr_err("%s: Calc. len %d != Passed len %d\n",
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__func__, calc_max_msg_len, desc->max_msg_len);
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return false;
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}
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return true;
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}
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/**
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* qmi_kernel_encode() - Encode to QMI message wire format
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* @desc: Pointer to structure descriptor.
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* @out_buf: Buffer to hold the encoded QMI message.
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* @out_buf_len: Length of the out buffer.
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* @in_c_struct: C Structure to be encoded.
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*
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* @return: size of encoded message on success, < 0 for error.
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*/
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int qmi_kernel_encode(struct msg_desc *desc,
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void *out_buf, uint32_t out_buf_len,
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void *in_c_struct)
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{
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int enc_level = 1;
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int ret, calc_max_msg_len;
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if (!desc || !desc->ei_array)
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return -EINVAL;
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if (!out_buf || !in_c_struct)
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return -EINVAL;
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if (desc->max_msg_len < out_buf_len)
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return -ETOOSMALL;
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ret = _qmi_kernel_encode(desc->ei_array, out_buf,
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in_c_struct, out_buf_len, enc_level);
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if (ret == -ETOOSMALL) {
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calc_max_msg_len = qmi_calc_max_msg_len(desc->ei_array, 1);
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pr_err("%s: Calc. len %d != Out buf len %d\n",
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__func__, calc_max_msg_len, out_buf_len);
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}
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return ret;
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}
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EXPORT_SYMBOL(qmi_kernel_encode);
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/**
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* qmi_encode_basic_elem() - Encodes elements of basic/primary data type
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* @buf_dst: Buffer to store the encoded information.
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* @buf_src: Buffer containing the elements to be encoded.
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* @elem_len: Number of elements, in the buf_src, to be encoded.
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* @elem_size: Size of a single instance of the element to be encoded.
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*
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* @return: number of bytes of encoded information.
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*
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* This function encodes the "elem_len" number of data elements, each of
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* size "elem_size" bytes from the source buffer "buf_src" and stores the
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* encoded information in the destination buffer "buf_dst". The elements are
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* of primary data type which include uint8_t - uint64_t or similar. This
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* function returns the number of bytes of encoded information.
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*/
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static int qmi_encode_basic_elem(void *buf_dst, void *buf_src,
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uint32_t elem_len, uint32_t elem_size)
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{
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uint32_t i, rc = 0;
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for (i = 0; i < elem_len; i++) {
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QMI_ENCDEC_ENCODE_N_BYTES(buf_dst, buf_src, elem_size);
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rc += elem_size;
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}
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return rc;
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}
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/**
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* qmi_encode_struct_elem() - Encodes elements of struct data type
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* @ei_array: Struct info array descibing the struct element.
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* @buf_dst: Buffer to store the encoded information.
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* @buf_src: Buffer containing the elements to be encoded.
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* @elem_len: Number of elements, in the buf_src, to be encoded.
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* @out_buf_len: Available space in the encode buffer.
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* @enc_level: Depth of the nested structure from the main structure.
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*
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* @return: Mumber of bytes of encoded information, on success.
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* < 0 on error.
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*
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* This function encodes the "elem_len" number of struct elements, each of
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* size "ei_array->elem_size" bytes from the source buffer "buf_src" and
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* stores the encoded information in the destination buffer "buf_dst". The
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* elements are of struct data type which includes any C structure. This
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* function returns the number of bytes of encoded information.
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*/
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static int qmi_encode_struct_elem(struct elem_info *ei_array,
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void *buf_dst, void *buf_src,
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uint32_t elem_len, uint32_t out_buf_len,
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int enc_level)
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{
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int i, rc, encoded_bytes = 0;
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struct elem_info *temp_ei = ei_array;
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for (i = 0; i < elem_len; i++) {
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rc = _qmi_kernel_encode(temp_ei->ei_array, buf_dst, buf_src,
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(out_buf_len - encoded_bytes),
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enc_level);
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if (rc < 0) {
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pr_err("%s: STRUCT Encode failure\n", __func__);
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return rc;
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}
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buf_dst = buf_dst + rc;
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buf_src = buf_src + temp_ei->elem_size;
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encoded_bytes += rc;
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}
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return encoded_bytes;
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}
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/**
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* skip_to_next_elem() - Skip to next element in the structure to be encoded
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* @ei_array: Struct info describing the element to be skipped.
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*
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* @return: Struct info of the next element that can be encoded.
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*
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* This function is used while encoding optional elements. If the flag
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* corresponding to an optional element is not set, then encoding the
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* optional element can be skipped. This function can be used to perform
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* that operation.
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*/
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static struct elem_info *skip_to_next_elem(struct elem_info *ei_array)
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{
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struct elem_info *temp_ei = ei_array;
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uint8_t tlv_type;
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do {
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tlv_type = temp_ei->tlv_type;
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temp_ei = temp_ei + 1;
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} while (tlv_type == temp_ei->tlv_type);
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return temp_ei;
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}
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/**
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* _qmi_kernel_encode() - Core Encode Function
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* @ei_array: Struct info array describing the structure to be encoded.
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* @out_buf: Buffer to hold the encoded QMI message.
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* @in_c_struct: Pointer to the C structure to be encoded.
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* @out_buf_len: Available space in the encode buffer.
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* @enc_level: Encode level to indicate the depth of the nested structure,
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* within the main structure, being encoded.
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*
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* @return: Number of bytes of encoded information, on success.
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* < 0 on error.
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*/
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static int _qmi_kernel_encode(struct elem_info *ei_array,
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void *out_buf, void *in_c_struct,
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uint32_t out_buf_len, int enc_level)
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{
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struct elem_info *temp_ei = ei_array;
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uint8_t opt_flag_value = 0;
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uint32_t data_len_value = 0, data_len_sz;
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uint8_t *buf_dst = (uint8_t *)out_buf;
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uint8_t *tlv_pointer;
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uint32_t tlv_len;
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uint8_t tlv_type;
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uint32_t encoded_bytes = 0;
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void *buf_src;
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int encode_tlv = 0;
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int rc;
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tlv_pointer = buf_dst;
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tlv_len = 0;
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buf_dst = buf_dst + (TLV_LEN_SIZE + TLV_TYPE_SIZE);
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while (temp_ei->data_type != QMI_EOTI) {
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buf_src = in_c_struct + temp_ei->offset;
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tlv_type = temp_ei->tlv_type;
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if (temp_ei->is_array == NO_ARRAY) {
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data_len_value = 1;
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} else if (temp_ei->is_array == STATIC_ARRAY) {
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data_len_value = temp_ei->elem_len;
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} else if (data_len_value <= 0 ||
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temp_ei->elem_len < data_len_value) {
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pr_err("%s: Invalid data length\n", __func__);
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return -EINVAL;
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}
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switch (temp_ei->data_type) {
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case QMI_OPT_FLAG:
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rc = qmi_encode_basic_elem(&opt_flag_value, buf_src,
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1, sizeof(uint8_t));
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if (opt_flag_value)
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temp_ei = temp_ei + 1;
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else
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temp_ei = skip_to_next_elem(temp_ei);
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break;
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case QMI_DATA_LEN:
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memcpy(&data_len_value, buf_src, temp_ei->elem_size);
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data_len_sz = temp_ei->elem_size == sizeof(uint8_t) ?
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sizeof(uint8_t) : sizeof(uint16_t);
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/* Check to avoid out of range buffer access */
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if ((data_len_sz + encoded_bytes + TLV_LEN_SIZE +
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TLV_TYPE_SIZE) > out_buf_len) {
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pr_err("%s: Too Small Buffer @DATA_LEN\n",
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__func__);
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return -ETOOSMALL;
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}
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rc = qmi_encode_basic_elem(buf_dst, &data_len_value,
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1, data_len_sz);
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if (data_len_value) {
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UPDATE_ENCODE_VARIABLES(temp_ei, buf_dst,
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encoded_bytes, tlv_len, encode_tlv, rc);
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encode_tlv = 0;
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} else {
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temp_ei = skip_to_next_elem(temp_ei);
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}
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break;
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case QMI_UNSIGNED_1_BYTE:
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case QMI_UNSIGNED_2_BYTE:
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case QMI_UNSIGNED_4_BYTE:
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case QMI_UNSIGNED_8_BYTE:
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case QMI_SIGNED_2_BYTE_ENUM:
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case QMI_SIGNED_4_BYTE_ENUM:
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/* Check to avoid out of range buffer access */
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if (((data_len_value * temp_ei->elem_size) +
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encoded_bytes + TLV_LEN_SIZE + TLV_TYPE_SIZE) >
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out_buf_len) {
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pr_err("%s: Too Small Buffer @data_type:%d\n",
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__func__, temp_ei->data_type);
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return -ETOOSMALL;
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}
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rc = qmi_encode_basic_elem(buf_dst, buf_src,
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data_len_value, temp_ei->elem_size);
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QMI_ENCODE_LOG_ELEM(enc_level, data_len_value,
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temp_ei->elem_size, buf_src);
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UPDATE_ENCODE_VARIABLES(temp_ei, buf_dst,
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encoded_bytes, tlv_len, encode_tlv, rc);
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break;
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case QMI_STRUCT:
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rc = qmi_encode_struct_elem(temp_ei, buf_dst, buf_src,
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||
|
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;
|
||
|
|
||
|
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);
|
||
|
QMI_ENCODE_LOG_TLV(tlv_type, tlv_len);
|
||
|
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;
|
||
|
}
|
||
|
}
|
||
|
QMI_ENCODE_LOG_MSG(out_buf, encoded_bytes);
|
||
|
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;
|
||
|
|
||
|
QMI_DECODE_LOG_MSG(in_buf, in_buf_len);
|
||
|
while (decoded_bytes < in_buf_len) {
|
||
|
if (dec_level == 1) {
|
||
|
tlv_pointer = buf_src;
|
||
|
QMI_ENCDEC_DECODE_TLV(&tlv_type,
|
||
|
&tlv_len, tlv_pointer);
|
||
|
QMI_DECODE_LOG_TLV(tlv_type, tlv_len);
|
||
|
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);
|
||
|
QMI_DECODE_LOG_ELEM(dec_level, data_len_value,
|
||
|
temp_ei->elem_size, buf_dst);
|
||
|
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");
|