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![Bjorn Andersson](/assets/img/avatar_default.png)
Add the helper library for encoding and decoding QMI encoded messages. The implementation is taken from lib/qmi_encdec.c of the Qualcomm kernel (msm-3.18). Modifications has been made to the public API, source buffers has been made const and the debug-logging part was omitted, for now. Acked-by: Chris Lew <clew@codeaurora.org> Tested-by: Chris Lew <clew@codeaurora.org> Tested-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> Signed-off-by: Andy Gross <andy.gross@linaro.org>
816 lines
24 KiB
C
816 lines
24 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Copyright (c) 2012-2015, The Linux Foundation. All rights reserved.
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* Copyright (C) 2017 Linaro Ltd.
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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/string.h>
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#include <linux/soc/qcom/qmi.h>
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#define QMI_ENCDEC_ENCODE_TLV(type, length, p_dst) do { \
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*p_dst++ = type; \
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*p_dst++ = ((u8)((length) & 0xFF)); \
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*p_dst++ = ((u8)(((length) >> 8) & 0xFF)); \
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} while (0)
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#define QMI_ENCDEC_DECODE_TLV(p_type, p_length, p_src) do { \
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*p_type = (u8)*p_src++; \
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*p_length = (u8)*p_src++; \
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*p_length |= ((u8)*p_src) << 8; \
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} while (0)
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#define QMI_ENCDEC_ENCODE_N_BYTES(p_dst, p_src, size) \
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do { \
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memcpy(p_dst, p_src, size); \
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p_dst = (u8 *)p_dst + size; \
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p_src = (u8 *)p_src + size; \
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} while (0)
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#define QMI_ENCDEC_DECODE_N_BYTES(p_dst, p_src, size) \
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do { \
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memcpy(p_dst, p_src, size); \
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p_dst = (u8 *)p_dst + size; \
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p_src = (u8 *)p_src + size; \
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} while (0)
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#define UPDATE_ENCODE_VARIABLES(temp_si, buf_dst, \
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encoded_bytes, tlv_len, encode_tlv, rc) \
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do { \
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buf_dst = (u8 *)buf_dst + rc; \
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encoded_bytes += rc; \
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tlv_len += rc; \
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temp_si = temp_si + 1; \
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encode_tlv = 1; \
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} while (0)
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#define UPDATE_DECODE_VARIABLES(buf_src, decoded_bytes, rc) \
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do { \
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buf_src = (u8 *)buf_src + rc; \
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decoded_bytes += rc; \
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} while (0)
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#define TLV_LEN_SIZE sizeof(u16)
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#define TLV_TYPE_SIZE sizeof(u8)
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#define OPTIONAL_TLV_TYPE_START 0x10
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static int qmi_encode(struct qmi_elem_info *ei_array, void *out_buf,
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const void *in_c_struct, u32 out_buf_len,
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int enc_level);
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static int qmi_decode(struct qmi_elem_info *ei_array, void *out_c_struct,
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const void *in_buf, u32 in_buf_len, int dec_level);
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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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* @level: Depth level of encoding/decoding to identify nested structures.
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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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* Return: struct info of the next element that can be encoded.
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*/
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static struct qmi_elem_info *skip_to_next_elem(struct qmi_elem_info *ei_array,
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int level)
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{
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struct qmi_elem_info *temp_ei = ei_array;
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u8 tlv_type;
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if (level > 1) {
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temp_ei = temp_ei + 1;
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} else {
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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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}
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return temp_ei;
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}
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/**
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* qmi_calc_min_msg_len() - Calculate the minimum 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 minimum length of the QMI message or 0 on error.
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*/
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static int qmi_calc_min_msg_len(struct qmi_elem_info *ei_array,
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int level)
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{
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int min_msg_len = 0;
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struct qmi_elem_info *temp_ei = ei_array;
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if (!ei_array)
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return min_msg_len;
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while (temp_ei->data_type != QMI_EOTI) {
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/* Optional elements do not count in minimum length */
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if (temp_ei->data_type == QMI_OPT_FLAG) {
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temp_ei = skip_to_next_elem(temp_ei, level);
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continue;
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}
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if (temp_ei->data_type == QMI_DATA_LEN) {
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min_msg_len += (temp_ei->elem_size == sizeof(u8) ?
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sizeof(u8) : sizeof(u16));
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temp_ei++;
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continue;
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} else if (temp_ei->data_type == QMI_STRUCT) {
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min_msg_len += qmi_calc_min_msg_len(temp_ei->ei_array,
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(level + 1));
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temp_ei++;
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} else if (temp_ei->data_type == QMI_STRING) {
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if (level > 1)
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min_msg_len += temp_ei->elem_len <= U8_MAX ?
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sizeof(u8) : sizeof(u16);
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min_msg_len += temp_ei->elem_len * temp_ei->elem_size;
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temp_ei++;
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} else {
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min_msg_len += (temp_ei->elem_len * temp_ei->elem_size);
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temp_ei++;
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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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min_msg_len += (TLV_TYPE_SIZE + TLV_LEN_SIZE);
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}
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return min_msg_len;
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}
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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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* 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 u8 - u64 or similar. This
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* function returns the number of bytes of encoded information.
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*
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* Return: The number of bytes of encoded information.
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*/
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static int qmi_encode_basic_elem(void *buf_dst, const void *buf_src,
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u32 elem_len, u32 elem_size)
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{
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u32 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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* 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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* Return: The number of bytes of encoded information on success or negative
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* errno on error.
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*/
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static int qmi_encode_struct_elem(struct qmi_elem_info *ei_array,
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void *buf_dst, const void *buf_src,
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u32 elem_len, u32 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 qmi_elem_info *temp_ei = ei_array;
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for (i = 0; i < elem_len; i++) {
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rc = qmi_encode(temp_ei->ei_array, buf_dst, buf_src,
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out_buf_len - encoded_bytes, 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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* qmi_encode_string_elem() - Encodes elements of string data type
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* @ei_array: Struct info array descibing the string 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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* @out_buf_len: Available space in the encode buffer.
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* @enc_level: Depth of the string element from the main structure.
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*
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* This function encodes a string element of maximum length "ei_array->elem_len"
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* bytes from the source buffer "buf_src" and stores the encoded information in
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* the destination buffer "buf_dst". This function returns the number of bytes
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* of encoded information.
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*
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* Return: The number of bytes of encoded information on success or negative
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* errno on error.
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*/
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static int qmi_encode_string_elem(struct qmi_elem_info *ei_array,
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void *buf_dst, const void *buf_src,
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u32 out_buf_len, int enc_level)
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{
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int rc;
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int encoded_bytes = 0;
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struct qmi_elem_info *temp_ei = ei_array;
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u32 string_len = 0;
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u32 string_len_sz = 0;
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string_len = strlen(buf_src);
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string_len_sz = temp_ei->elem_len <= U8_MAX ?
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sizeof(u8) : sizeof(u16);
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if (string_len > temp_ei->elem_len) {
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pr_err("%s: String to be encoded is longer - %d > %d\n",
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__func__, string_len, temp_ei->elem_len);
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return -EINVAL;
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}
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if (enc_level == 1) {
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if (string_len + TLV_LEN_SIZE + TLV_TYPE_SIZE >
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out_buf_len) {
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pr_err("%s: Output len %d > Out Buf len %d\n",
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__func__, string_len, out_buf_len);
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return -ETOOSMALL;
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}
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} else {
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if (string_len + string_len_sz > out_buf_len) {
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pr_err("%s: Output len %d > Out Buf len %d\n",
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__func__, string_len, out_buf_len);
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return -ETOOSMALL;
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}
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rc = qmi_encode_basic_elem(buf_dst, &string_len,
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1, string_len_sz);
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encoded_bytes += rc;
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}
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rc = qmi_encode_basic_elem(buf_dst + encoded_bytes, buf_src,
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string_len, temp_ei->elem_size);
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encoded_bytes += rc;
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return encoded_bytes;
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}
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/**
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* qmi_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: The number of bytes of encoded information on success or negative
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* errno on error.
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*/
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static int qmi_encode(struct qmi_elem_info *ei_array, void *out_buf,
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const void *in_c_struct, u32 out_buf_len,
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int enc_level)
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{
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struct qmi_elem_info *temp_ei = ei_array;
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u8 opt_flag_value = 0;
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u32 data_len_value = 0, data_len_sz;
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u8 *buf_dst = (u8 *)out_buf;
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u8 *tlv_pointer;
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u32 tlv_len;
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u8 tlv_type;
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u32 encoded_bytes = 0;
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const void *buf_src;
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int encode_tlv = 0;
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int rc;
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if (!ei_array)
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return 0;
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tlv_pointer = buf_dst;
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tlv_len = 0;
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if (enc_level == 1)
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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->array_type == NO_ARRAY) {
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data_len_value = 1;
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} else if (temp_ei->array_type == 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(u8));
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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, enc_level);
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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(u8) ?
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sizeof(u8) : sizeof(u16);
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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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UPDATE_ENCODE_VARIABLES(temp_ei, buf_dst,
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encoded_bytes, tlv_len,
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encode_tlv, rc);
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if (!data_len_value)
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temp_ei = skip_to_next_elem(temp_ei, enc_level);
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else
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encode_tlv = 0;
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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,
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temp_ei->elem_size);
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UPDATE_ENCODE_VARIABLES(temp_ei, buf_dst,
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encoded_bytes, tlv_len,
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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,
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out_buf_len - encoded_bytes,
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enc_level + 1);
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if (rc < 0)
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return rc;
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UPDATE_ENCODE_VARIABLES(temp_ei, buf_dst,
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encoded_bytes, tlv_len,
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encode_tlv, rc);
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break;
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case QMI_STRING:
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rc = qmi_encode_string_elem(temp_ei, 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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return rc;
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UPDATE_ENCODE_VARIABLES(temp_ei, buf_dst,
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encoded_bytes, tlv_len,
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encode_tlv, rc);
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break;
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default:
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pr_err("%s: Unrecognized data type\n", __func__);
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return -EINVAL;
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}
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if (encode_tlv && enc_level == 1) {
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QMI_ENCDEC_ENCODE_TLV(tlv_type, tlv_len, tlv_pointer);
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encoded_bytes += (TLV_TYPE_SIZE + TLV_LEN_SIZE);
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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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encode_tlv = 0;
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}
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}
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return encoded_bytes;
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}
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/**
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* qmi_decode_basic_elem() - Decodes elements of basic/primary data type
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* @buf_dst: Buffer to store the decoded element.
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* @buf_src: Buffer containing the elements in QMI wire format.
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* @elem_len: Number of elements to be decoded.
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* @elem_size: Size of a single instance of the element to be decoded.
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*
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* This function decodes the "elem_len" number of elements in QMI wire format,
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* each of size "elem_size" bytes from the source buffer "buf_src" and stores
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* the decoded elements in the destination buffer "buf_dst". The elements are
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* of primary data type which include u8 - u64 or similar. This
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* function returns the number of bytes of decoded information.
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*
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* Return: The total size of the decoded data elements, in bytes.
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*/
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static int qmi_decode_basic_elem(void *buf_dst, const void *buf_src,
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u32 elem_len, u32 elem_size)
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{
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u32 i, rc = 0;
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for (i = 0; i < elem_len; i++) {
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QMI_ENCDEC_DECODE_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_decode_struct_elem() - Decodes elements of struct data type
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* @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");
|