X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=drivers%2Fi2c%2Fbusses%2Fi2c-i801.c;h=eb3627f35d12002776447982d493835fe36dc064;hb=ba9ad2af7019956b990ad654c56da5bac1e8b71b;hp=08847e8b899872e2bc1bffd1d0936f63ee4f38d7;hpb=603616017c35f4d0fbdbcace72adf9bf949c4a65;p=platform%2Fkernel%2Flinux-starfive.git

diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index 08847e8..eb3627f 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -146,6 +146,7 @@
 #define SMBHSTCFG_HST_EN	1
 #define SMBHSTCFG_SMB_SMI_EN	2
 #define SMBHSTCFG_I2C_EN	4
+#define SMBHSTCFG_SPD_WD	0x10
 
 /* TCO configuration bits for TCOCTL */
 #define TCOCTL_EN		0x0100
@@ -865,9 +866,16 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr,
 		block = 1;
 		break;
 	case I2C_SMBUS_I2C_BLOCK_DATA:
-		/* NB: page 240 of ICH5 datasheet shows that the R/#W
-		 * bit should be cleared here, even when reading */
-		outb_p((addr & 0x7f) << 1, SMBHSTADD(priv));
+		/*
+		 * NB: page 240 of ICH5 datasheet shows that the R/#W
+		 * bit should be cleared here, even when reading.
+		 * However if SPD Write Disable is set (Lynx Point and later),
+		 * the read will fail if we don't set the R/#W bit.
+		 */
+		outb_p(((addr & 0x7f) << 1) |
+		       ((priv->original_hstcfg & SMBHSTCFG_SPD_WD) ?
+			(read_write & 0x01) : 0),
+		       SMBHSTADD(priv));
 		if (read_write == I2C_SMBUS_READ) {
 			/* NB: page 240 of ICH5 datasheet also shows
 			 * that DATA1 is the cmd field when reading */
@@ -1573,6 +1581,8 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
 		/* Disable SMBus interrupt feature if SMBus using SMI# */
 		priv->features &= ~FEATURE_IRQ;
 	}
+	if (temp & SMBHSTCFG_SPD_WD)
+		dev_info(&dev->dev, "SPD Write Disable is set\n");
 
 	/* Clear special mode bits */
 	if (priv->features & (FEATURE_SMBUS_PEC | FEATURE_BLOCK_BUFFER))