static int tpm_ibmvtpm_probe()

in tpm/tpm_ibmvtpm.c [598:718]

• 97 lines of code
• 21 McCabe index (conditional complexity)

static int tpm_ibmvtpm_probe(struct vio_dev *vio_dev,
				   const struct vio_device_id *id)
{
	struct ibmvtpm_dev *ibmvtpm;
	struct device *dev = &vio_dev->dev;
	struct ibmvtpm_crq_queue *crq_q;
	struct tpm_chip *chip;
	int rc = -ENOMEM, rc1;

	chip = tpmm_chip_alloc(dev, &tpm_ibmvtpm);
	if (IS_ERR(chip))
		return PTR_ERR(chip);

	ibmvtpm = kzalloc(sizeof(struct ibmvtpm_dev), GFP_KERNEL);
	if (!ibmvtpm) {
		dev_err(dev, "kzalloc for ibmvtpm failed\n");
		goto cleanup;
	}

	ibmvtpm->dev = dev;
	ibmvtpm->vdev = vio_dev;

	crq_q = &ibmvtpm->crq_queue;
	crq_q->crq_addr = (struct ibmvtpm_crq *)get_zeroed_page(GFP_KERNEL);
	if (!crq_q->crq_addr) {
		dev_err(dev, "Unable to allocate memory for crq_addr\n");
		goto cleanup;
	}

	crq_q->num_entry = CRQ_RES_BUF_SIZE / sizeof(*crq_q->crq_addr);
	init_waitqueue_head(&crq_q->wq);
	ibmvtpm->crq_dma_handle = dma_map_single(dev, crq_q->crq_addr,
						 CRQ_RES_BUF_SIZE,
						 DMA_BIDIRECTIONAL);

	if (dma_mapping_error(dev, ibmvtpm->crq_dma_handle)) {
		dev_err(dev, "dma mapping failed\n");
		goto cleanup;
	}

	rc = plpar_hcall_norets(H_REG_CRQ, vio_dev->unit_address,
				ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE);
	if (rc == H_RESOURCE)
		rc = ibmvtpm_reset_crq(ibmvtpm);

	if (rc) {
		dev_err(dev, "Unable to register CRQ rc=%d\n", rc);
		goto reg_crq_cleanup;
	}

	rc = request_irq(vio_dev->irq, ibmvtpm_interrupt, 0,
			 tpm_ibmvtpm_driver_name, ibmvtpm);
	if (rc) {
		dev_err(dev, "Error %d register irq 0x%x\n", rc, vio_dev->irq);
		goto init_irq_cleanup;
	}

	rc = vio_enable_interrupts(vio_dev);
	if (rc) {
		dev_err(dev, "Error %d enabling interrupts\n", rc);
		goto init_irq_cleanup;
	}

	init_waitqueue_head(&ibmvtpm->wq);

	crq_q->index = 0;

	dev_set_drvdata(&chip->dev, ibmvtpm);

	spin_lock_init(&ibmvtpm->rtce_lock);

	rc = ibmvtpm_crq_send_init(ibmvtpm);
	if (rc)
		goto init_irq_cleanup;

	rc = ibmvtpm_crq_get_version(ibmvtpm);
	if (rc)
		goto init_irq_cleanup;

	rc = ibmvtpm_crq_get_rtce_size(ibmvtpm);
	if (rc)
		goto init_irq_cleanup;

	if (!wait_event_timeout(ibmvtpm->crq_queue.wq,
				ibmvtpm->rtce_buf != NULL,
				HZ)) {
		dev_err(dev, "CRQ response timed out\n");
		goto init_irq_cleanup;
	}


	if (!strcmp(id->compat, "IBM,vtpm20"))
		chip->flags |= TPM_CHIP_FLAG_TPM2;

	rc = tpm_get_timeouts(chip);
	if (rc)
		goto init_irq_cleanup;

	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
		rc = tpm2_get_cc_attrs_tbl(chip);
		if (rc)
			goto init_irq_cleanup;
	}

	return tpm_chip_register(chip);
init_irq_cleanup:
	do {
		rc1 = plpar_hcall_norets(H_FREE_CRQ, vio_dev->unit_address);
	} while (rc1 == H_BUSY || H_IS_LONG_BUSY(rc1));
reg_crq_cleanup:
	dma_unmap_single(dev, ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE,
			 DMA_BIDIRECTIONAL);
cleanup:
	if (ibmvtpm) {
		if (crq_q->crq_addr)
			free_page((unsigned long)crq_q->crq_addr);
		kfree(ibmvtpm);
	}

	return rc;
}