media: venus: hfi: Correct session init return error

The hfi_session_init can be called many times and it returns
EINVAL when the session was already initialized. This error code
(EINVAL) is confusing for the callers. Change hfi_session_init to
return EALREADY error code when the session has been already
initialized.
Tested-by: Fritz Koenig <frkoenig@chromium.org>
Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/platform/qcom/venus/hfi.c

@@ -221,7 +221,7 @@ int hfi_session_init(struct venus_inst *inst, u32 pixfmt)
 	mutex_unlock(&core->lock);
 
 	if (inst->state != INST_UNINIT)
-		return -EINVAL;
+		return -EALREADY;
 
 	inst->hfi_codec = to_codec_type(pixfmt);
 	reinit_completion(&inst->done);

drivers/media/platform/qcom/venus/vdec.c

@@ -761,7 +761,7 @@ static int vdec_session_init(struct venus_inst *inst)
 	int ret;
 
 	ret = hfi_session_init(inst, inst->fmt_out->pixfmt);
-	if (ret == -EINVAL)
+	if (ret == -EALREADY)
 		return 0;
 	else if (ret)
 		return ret;

drivers/media/platform/qcom/venus/venc.c

@@ -725,7 +725,7 @@ static int venc_init_session(struct venus_inst *inst)
 	int ret;
 
 	ret = hfi_session_init(inst, inst->fmt_cap->pixfmt);
-	if (ret == -EINVAL)
+	if (ret == -EALREADY)
 		return 0;
 	else if (ret)
 		return ret;