[radeon-alex:drm-next-4.21-wip 10/27] drivers/gpu/drm/amd/amdgpu/vcn_v1_0.c:1174 vcn_v1_0_stop_dpg_mode() error: uninitialized symbol 'ret_code'.

[Dan Carpenter]

tree:   git://people.freedesktop.org/~agd5f/linux.git drm-next-4.21-wip
head:   6af94a9d0e185f48bef5cc1372f3ada89d003858
commit: 15296db70619984157e60666da5da8994a66870e [10/27] drm/amdgpu/vcn:Add ring W/R PTR check for VCN DPG mode stop

smatch warnings:
drivers/gpu/drm/amd/amdgpu/vcn_v1_0.c:1174 vcn_v1_0_stop_dpg_mode() error: uninitialized symbol 'ret_code'.

git remote add radeon-alex git://people.freedesktop.org/~agd5f/linux.git
git remote update radeon-alex
git checkout 15296db70619984157e60666da5da8994a66870e
vim +/ret_code +1174 drivers/gpu/drm/amd/amdgpu/vcn_v1_0.c

88b5af70 Leo Liu   2016-12-28  1164  
63e9bb1d James Zhu 2018-09-21  1165  static int vcn_v1_0_stop_dpg_mode(struct amdgpu_device *adev)
63e9bb1d James Zhu 2018-09-21  1166  {
63e9bb1d James Zhu 2018-09-21  1167  	int ret_code;
63e9bb1d James Zhu 2018-09-21  1168  
b17c5249 James Zhu 2018-10-02  1169  	/* Wait for power status to be UVD_POWER_STATUS__UVD_POWER_STATUS_TILES_OFF */
b17c5249 James Zhu 2018-10-02  1170  	SOC15_WAIT_ON_RREG(UVD, 0, mmUVD_POWER_STATUS,
b17c5249 James Zhu 2018-10-02  1171  			UVD_POWER_STATUS__UVD_POWER_STATUS_TILES_OFF,
63e9bb1d James Zhu 2018-09-21  1172  			UVD_POWER_STATUS__UVD_POWER_STATUS_MASK, ret_code);
                                                                                                 ^^^^^^^^
ret_code is only set on timeout.

63e9bb1d James Zhu 2018-09-21  1173  
15296db7 James Zhu 2018-10-03 @1174  	if (ret_code) {
                                            ^^^^^^^^
uninitialized on the success path.

15296db7 James Zhu 2018-10-03  1175  		int tmp = RREG32_SOC15(UVD, 0, mmUVD_RBC_RB_WPTR) & 0x7FFFFFFF;
15296db7 James Zhu 2018-10-03  1176  		/* wait for read ptr to be equal to write ptr */
15296db7 James Zhu 2018-10-03  1177  		SOC15_WAIT_ON_RREG(UVD, 0, mmUVD_RBC_RB_RPTR, tmp, 0xFFFFFFFF, ret_code);
15296db7 James Zhu 2018-10-03  1178  
15296db7 James Zhu 2018-10-03  1179  		SOC15_WAIT_ON_RREG(UVD, 0, mmUVD_POWER_STATUS,
15296db7 James Zhu 2018-10-03  1180  			UVD_POWER_STATUS__UVD_POWER_STATUS_TILES_OFF,
15296db7 James Zhu 2018-10-03  1181  			UVD_POWER_STATUS__UVD_POWER_STATUS_MASK, ret_code);
15296db7 James Zhu 2018-10-03  1182  	}
15296db7 James Zhu 2018-10-03  1183  
63e9bb1d James Zhu 2018-09-21  1184  	/* disable dynamic power gating mode */
63e9bb1d James Zhu 2018-09-21  1185  	WREG32_P(SOC15_REG_OFFSET(UVD, 0, mmUVD_POWER_STATUS), 0,
63e9bb1d James Zhu 2018-09-21  1186  			~UVD_POWER_STATUS__UVD_PG_MODE_MASK);
63e9bb1d James Zhu 2018-09-21  1187  
63e9bb1d James Zhu 2018-09-21  1188  	return 0;
63e9bb1d James Zhu 2018-09-21  1189  }
63e9bb1d James Zhu 2018-09-21  1190  

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