tpm: pay attention to IRQ info from PNP

If we discover the TIS TPM device via PNP, use the PNP IRQ information rather
than probing for an IRQ.  If PNP shows no IRQ, run the TPM in polling mode.

Tested-by: <valdis.kletnieks@vt.edu>
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Kylene Hall <kjhall@us.ibm.com>
Cc: <tpm@selhorst.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/char/tpm/tpm_tis.c

@@ -435,17 +435,12 @@ module_param(interrupts, bool, 0444);
 MODULE_PARM_DESC(interrupts, "Enable interrupts");
 
 static int tpm_tis_init(struct device *dev, resource_size_t start,
-			resource_size_t len)
+			resource_size_t len, unsigned int irq)
 {
 	u32 vendor, intfcaps, intmask;
 	int rc, i;
 	struct tpm_chip *chip;
 
-	if (!start)
-		start = TIS_MEM_BASE;
-	if (!len)
-		len = TIS_MEM_LEN;
-
 	if (!(chip = tpm_register_hardware(dev, &tpm_tis)))
 		return -ENODEV;
 
@@ -512,7 +507,9 @@ static int tpm_tis_init(struct device *dev, resource_size_t start,
 	iowrite32(intmask,
 		  chip->vendor.iobase +
 		  TPM_INT_ENABLE(chip->vendor.locality));
-	if (interrupts) {
+	if (interrupts)
+		chip->vendor.irq = irq;
+	if (interrupts && !chip->vendor.irq) {
 		chip->vendor.irq =
 		    ioread8(chip->vendor.iobase +
 			    TPM_INT_VECTOR(chip->vendor.locality));
@@ -597,10 +594,17 @@ static int __devinit tpm_tis_pnp_init(struct pnp_dev *pnp_dev,
 				      const struct pnp_device_id *pnp_id)
 {
 	resource_size_t start, len;
+	unsigned int irq = 0;
+
 	start = pnp_mem_start(pnp_dev, 0);
 	len = pnp_mem_len(pnp_dev, 0);
 
-	return tpm_tis_init(&pnp_dev->dev, start, len);
+	if (pnp_irq_valid(pnp_dev, 0))
+		irq = pnp_irq(pnp_dev, 0);
+	else
+		interrupts = 0;
+
+	return tpm_tis_init(&pnp_dev->dev, start, len, irq);
 }
 
 static int tpm_tis_pnp_suspend(struct pnp_dev *dev, pm_message_t msg)
@@ -660,7 +664,7 @@ static int __init init_tis(void)
 			return rc;
 		if (IS_ERR(pdev=platform_device_register_simple("tpm_tis", -1, NULL, 0)))
 			return PTR_ERR(pdev);
-		if((rc=tpm_tis_init(&pdev->dev, 0, 0)) != 0) {
+		if((rc=tpm_tis_init(&pdev->dev, TIS_MEM_BASE, TIS_MEM_LEN, 0)) != 0) {
 			platform_device_unregister(pdev);
 			driver_unregister(&tis_drv);
 		}