[PATCH 4/4] i2c: pasemi: Log bus reset causes

[Sven Peter via B4 Relay <devnull+sven.svenpeter.dev@kernel.org>]

From: Hector Martin <marcan@marcan.st>

This ensures we get all information we need to debug issues when users
forward us their logs.

Signed-off-by: Hector Martin <marcan@marcan.st>
Signed-off-by: Sven Peter <sven@svenpeter.dev>
---
 drivers/i2c/busses/i2c-pasemi-core.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/i2c/busses/i2c-pasemi-core.c b/drivers/i2c/busses/i2c-pasemi-core.c
index 8f0ba975172f..ae0181a76470 100644
--- a/drivers/i2c/busses/i2c-pasemi-core.c
+++ b/drivers/i2c/busses/i2c-pasemi-core.c
@@ -21,6 +21,7 @@
 /* Register offsets */
 #define REG_MTXFIFO	0x00
 #define REG_MRXFIFO	0x04
+#define REG_XFSTA	0x0c
 #define REG_SMSTA	0x14
 #define REG_IMASK	0x18
 #define REG_CTL		0x1c
@@ -84,7 +85,7 @@ static void pasemi_reset(struct pasemi_smbus *smbus)
 
 static int pasemi_smb_clear(struct pasemi_smbus *smbus)
 {
-	unsigned int status;
+	unsigned int status, xfstatus;
 	int timeout = TRANSFER_TIMEOUT_MS;
 
 	status = reg_read(smbus, REG_SMSTA);
@@ -95,15 +96,21 @@ static int pasemi_smb_clear(struct pasemi_smbus *smbus)
 		status = reg_read(smbus, REG_SMSTA);
 	}
 
+	xfstatus = reg_read(smbus, REG_XFSTA);
+
 	if (timeout < 0) {
-		dev_warn(smbus->dev, "Bus is still stuck (status 0x%08x)\n", status);
+		dev_warn(smbus->dev, "Bus is still stuck (status 0x%08x xfstatus 0x%08x)\n",
+			 status, xfstatus);
 		return -EIO;
 	}
 
 	/* If any badness happened or there is data in the FIFOs, reset the FIFOs */
 	if ((status & (SMSTA_MRNE | SMSTA_JMD | SMSTA_MTO | SMSTA_TOM | SMSTA_MTN | SMSTA_MTA)) ||
-		!(status & SMSTA_MTE))
+		!(status & SMSTA_MTE)) {
+		dev_warn(smbus->dev, "Issuing reset due to status 0x%08x (xfstatus 0x%08x)\n",
+			 status, xfstatus);
 		pasemi_reset(smbus);
+	}
 
 	/* Clear the flags */
 	reg_write(smbus, REG_SMSTA, status);

-- 
2.34.1