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b047cbe5e5
The msm_dp_utils_pack_sdp_header() accepts an unlimited-size u32 pointer
for the header output, while it expects a two-element array. It performs
a sizeof check which is always true on 64-bit platforms (since
sizeof(u32*) is 8) and is always false on 32-bit platforms. It returns
an error code which nobody actually checks.
Fix the function interface to accept u32[2] and return void, skipping
all the checks.
Fixes: 55fb8ffc18 ("drm/msm/dp: add VSC SDP support for YUV420 over DP")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/626806/
Link: https://lore.kernel.org/r/20241202-fd-dp-audio-fixup-v2-2-d9187ea96dad@linaro.org
[quic_abhinavk@quicinc.com: minor fix in the commit message]
Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
88 lines
1.8 KiB
C
88 lines
1.8 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* Copyright (c) 2024, The Linux Foundation. All rights reserved.
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*/
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#include <linux/types.h>
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#include "dp_utils.h"
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#define DP_SDP_HEADER_SIZE 8
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u8 msm_dp_utils_get_g0_value(u8 data)
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{
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u8 c[4];
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u8 g[4];
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u8 ret_data = 0;
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u8 i;
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for (i = 0; i < 4; i++)
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c[i] = (data >> i) & 0x01;
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g[0] = c[3];
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g[1] = c[0] ^ c[3];
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g[2] = c[1];
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g[3] = c[2];
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for (i = 0; i < 4; i++)
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ret_data = ((g[i] & 0x01) << i) | ret_data;
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return ret_data;
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}
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u8 msm_dp_utils_get_g1_value(u8 data)
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{
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u8 c[4];
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u8 g[4];
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u8 ret_data = 0;
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u8 i;
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for (i = 0; i < 4; i++)
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c[i] = (data >> i) & 0x01;
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g[0] = c[0] ^ c[3];
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g[1] = c[0] ^ c[1] ^ c[3];
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g[2] = c[1] ^ c[2];
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g[3] = c[2] ^ c[3];
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for (i = 0; i < 4; i++)
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ret_data = ((g[i] & 0x01) << i) | ret_data;
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return ret_data;
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}
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u8 msm_dp_utils_calculate_parity(u32 data)
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{
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u8 x0 = 0;
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u8 x1 = 0;
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u8 ci = 0;
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u8 iData = 0;
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u8 i = 0;
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u8 parity_byte;
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u8 num_byte = (data & 0xFF00) > 0 ? 8 : 2;
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for (i = 0; i < num_byte; i++) {
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iData = (data >> i * 4) & 0xF;
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ci = iData ^ x1;
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x1 = x0 ^ msm_dp_utils_get_g1_value(ci);
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x0 = msm_dp_utils_get_g0_value(ci);
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}
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parity_byte = x1 | (x0 << 4);
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return parity_byte;
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}
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void msm_dp_utils_pack_sdp_header(struct dp_sdp_header *sdp_header, u32 header_buff[2])
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{
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header_buff[0] = FIELD_PREP(HEADER_0_MASK, sdp_header->HB0) |
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FIELD_PREP(PARITY_0_MASK, msm_dp_utils_calculate_parity(sdp_header->HB0)) |
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FIELD_PREP(HEADER_1_MASK, sdp_header->HB1) |
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FIELD_PREP(PARITY_1_MASK, msm_dp_utils_calculate_parity(sdp_header->HB1));
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header_buff[1] = FIELD_PREP(HEADER_2_MASK, sdp_header->HB2) |
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FIELD_PREP(PARITY_2_MASK, msm_dp_utils_calculate_parity(sdp_header->HB2)) |
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FIELD_PREP(HEADER_3_MASK, sdp_header->HB3) |
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FIELD_PREP(PARITY_3_MASK, msm_dp_utils_calculate_parity(sdp_header->HB3));
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}
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