3 files changed, 52 insertions, 17 deletions

diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c
index 18beb0ad7bf..a076129de7e 100644
--- a/drivers/i2c/busses/i2c-mpc.c
+++ b/drivers/i2c/busses/i2c-mpc.c
@@ -99,7 +99,7 @@ static int i2c_wait(struct mpc_i2c *i2c, unsigned timeout, int writing)
 	u32 x;
 	int result = 0;
 
-	if (i2c->irq == 0)
+	if (i2c->irq == NO_IRQ)
 	{
 		while (!(readb(i2c->base + MPC_I2C_SR) & CSR_MIF)) {
 			schedule();
@@ -329,10 +329,9 @@ static int fsl_i2c_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	i2c->irq = platform_get_irq(pdev, 0);
-	if (i2c->irq < 0) {
-		result = -ENXIO;
-		goto fail_get_irq;
-	}
+	if (i2c->irq < 0)
+		i2c->irq = NO_IRQ; /* Use polling */
+
 	i2c->flags = pdata->device_flags;
 	init_waitqueue_head(&i2c->queue);
 
@@ -344,7 +343,7 @@ static int fsl_i2c_probe(struct platform_device *pdev)
 		goto fail_map;
 	}
 
-	if (i2c->irq != 0)
+	if (i2c->irq != NO_IRQ)
 		if ((result = request_irq(i2c->irq, mpc_i2c_isr,
 					  IRQF_SHARED, "i2c-mpc", i2c)) < 0) {
 			printk(KERN_ERR
@@ -367,12 +366,11 @@ static int fsl_i2c_probe(struct platform_device *pdev)
 	return result;
 
       fail_add:
-	if (i2c->irq != 0)
+	if (i2c->irq != NO_IRQ)
 		free_irq(i2c->irq, i2c);
       fail_irq:
 	iounmap(i2c->base);
       fail_map:
-      fail_get_irq:
 	kfree(i2c);
 	return result;
 };
@@ -384,7 +382,7 @@ static int fsl_i2c_remove(struct platform_device *pdev)
 	i2c_del_adapter(&i2c->adap);
 	platform_set_drvdata(pdev, NULL);
 
-	if (i2c->irq != 0)
+	if (i2c->irq != NO_IRQ)
 		free_irq(i2c->irq, i2c);
 
 	iounmap(i2c->base);
diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c
index fdc9ad805e3..ac916596858 100644
--- a/drivers/i2c/busses/i2c-piix4.c
+++ b/drivers/i2c/busses/i2c-piix4.c
@@ -104,10 +104,31 @@ MODULE_PARM_DESC(force_addr,
 static int piix4_transaction(void);
 
 static unsigned short piix4_smba;
+static int srvrworks_csb5_delay;
 static struct pci_driver piix4_driver;
 static struct i2c_adapter piix4_adapter;
 
-static struct dmi_system_id __devinitdata piix4_dmi_table[] = {
+static struct dmi_system_id __devinitdata piix4_dmi_blacklist[] = {
+	{
+		.ident = "Sapphire AM2RD790",
+		.matches = {
+			DMI_MATCH(DMI_BOARD_VENDOR, "SAPPHIRE Inc."),
+			DMI_MATCH(DMI_BOARD_NAME, "PC-AM2RD790"),
+		},
+	},
+	{
+		.ident = "DFI Lanparty UT 790FX",
+		.matches = {
+			DMI_MATCH(DMI_BOARD_VENDOR, "DFI Inc."),
+			DMI_MATCH(DMI_BOARD_NAME, "LP UT 790FX"),
+		},
+	},
+	{ }
+};
+
+/* The IBM entry is in a separate table because we only check it
+   on Intel-based systems */
+static struct dmi_system_id __devinitdata piix4_dmi_ibm[] = {
 	{
 		.ident = "IBM",
 		.matches = { DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
@@ -122,8 +143,20 @@ static int __devinit piix4_setup(struct pci_dev *PIIX4_dev,
 
 	dev_info(&PIIX4_dev->dev, "Found %s device\n", pci_name(PIIX4_dev));
 
+	if ((PIIX4_dev->vendor == PCI_VENDOR_ID_SERVERWORKS) &&
+	    (PIIX4_dev->device == PCI_DEVICE_ID_SERVERWORKS_CSB5))
+		srvrworks_csb5_delay = 1;
+
+	/* On some motherboards, it was reported that accessing the SMBus
+	   caused severe hardware problems */
+	if (dmi_check_system(piix4_dmi_blacklist)) {
+		dev_err(&PIIX4_dev->dev,
+			"Accessing the SMBus on this system is unsafe!\n");
+		return -EPERM;
+	}
+
 	/* Don't access SMBus on IBM systems which get corrupted eeproms */
-	if (dmi_check_system(piix4_dmi_table) &&
+	if (dmi_check_system(piix4_dmi_ibm) &&
 			PIIX4_dev->vendor == PCI_VENDOR_ID_INTEL) {
 		dev_err(&PIIX4_dev->dev, "IBM system detected; this module "
 			"may corrupt your serial eeprom! Refusing to load "
@@ -230,10 +263,14 @@ static int piix4_transaction(void)
 	outb_p(inb(SMBHSTCNT) | 0x040, SMBHSTCNT);
 
 	/* We will always wait for a fraction of a second! (See PIIX4 docs errata) */
-	do {
+	if (srvrworks_csb5_delay) /* Extra delay for SERVERWORKS_CSB5 */
+		msleep(2);
+	else
+		msleep(1);
+
+	while ((timeout++ < MAX_TIMEOUT) &&
+	       ((temp = inb_p(SMBHSTSTS)) & 0x01))
 		msleep(1);
-		temp = inb_p(SMBHSTSTS);
-	} while ((temp & 0x01) && (timeout++ < MAX_TIMEOUT));
 
 	/* If the SMBus is still busy, we give up */
 	if (timeout >= MAX_TIMEOUT) {
diff --git a/drivers/i2c/busses/i2c-sibyte.c b/drivers/i2c/busses/i2c-sibyte.c
index 8fbbdb4c2f3..114634da6c6 100644
--- a/drivers/i2c/busses/i2c-sibyte.c
+++ b/drivers/i2c/busses/i2c-sibyte.c
@@ -132,14 +132,14 @@ static const struct i2c_algorithm i2c_sibyte_algo = {
 /*
  * registering functions to load algorithms at runtime
  */
-int __init i2c_sibyte_add_bus(struct i2c_adapter *i2c_adap, int speed)
+static int __init i2c_sibyte_add_bus(struct i2c_adapter *i2c_adap, int speed)
 {
 	struct i2c_algo_sibyte_data *adap = i2c_adap->algo_data;
 
-	/* register new adapter to i2c module... */
+	/* Register new adapter to i2c module... */
 	i2c_adap->algo = &i2c_sibyte_algo;
 
-	/* Set the frequency to 100 kHz */
+	/* Set the requested frequency. */
 	csr_out32(speed, SMB_CSR(adap,R_SMB_FREQ));
 	csr_out32(0, SMB_CSR(adap,R_SMB_CONTROL));