[PATCH 3/3] EDAC: i5400: disable error reporting at teardown and refactor helper

[Tushar Tibude <tushar.tibude1000@gmail.com>]

If error reporting is enabled during initialization but initialization
fails immediately after, or during normal driver teardown, error reporting
is left enabled in the mask register even after exit.

Replace i5400_enable_error_reporting() with i5400_set_error_reporting()
to combine enabling/disabling. Disable reporting at initialization
failure and driver exit, before call to i5400_put_devices() for cleanup.

This ensures clean hardware handling by disabling any unused error
reporting bits before exiting.

Signed-off-by: Tushar Tibude <tushar.tibude1000@gmail.com>
---
 drivers/edac/i5400_edac.c | 33 ++++++++++++++++++++++++---------
 1 file changed, 24 insertions(+), 9 deletions(-)

diff --git a/drivers/edac/i5400_edac.c b/drivers/edac/i5400_edac.c
index fb49a1d1d..ae4f92989 100644
--- a/drivers/edac/i5400_edac.c
+++ b/drivers/edac/i5400_edac.c
@@ -353,6 +353,9 @@ struct i5400_pvt {
 	/* Actual values for this controller */
 	int maxch;				/* Max channels */
 	int maxdimmperch;			/* Max DIMMs per channel */
+
+	/* Hardware error reporting status */
+	bool enabled_error_reporting;
 };
 
 /* I5400 MCH error information retrieved from Hardware */
@@ -1223,10 +1226,10 @@ static int i5400_init_dimms(struct mem_ctl_info *mci)
 }
 
 /*
- *	i5400_enable_error_reporting
- *			Turn on the memory reporting features of the hardware
+ *	i5400_set_error_reporting
+ *			Turn on/off the memory reporting features of the hardware
  */
-static void i5400_enable_error_reporting(struct mem_ctl_info *mci)
+static void i5400_set_error_reporting(struct mem_ctl_info *mci, bool enable)
 {
 	struct i5400_pvt *pvt;
 	u32 fbd_error_mask;
@@ -1237,8 +1240,11 @@ static void i5400_enable_error_reporting(struct mem_ctl_info *mci)
 	pci_read_config_dword(pvt->branchmap_werrors, EMASK_FBD,
 			&fbd_error_mask);
 
-	/* Enable with a '0' */
-	fbd_error_mask &= ~(ENABLE_EMASK_ALL);
+	/* Enable with 0, disable with 1 */
+	if (enable)
+		fbd_error_mask &= ~(ENABLE_EMASK_ALL);
+	else
+		fbd_error_mask |= ENABLE_EMASK_ALL;
 
 	pci_write_config_dword(pvt->branchmap_werrors, EMASK_FBD,
 			fbd_error_mask);
@@ -1319,17 +1325,19 @@ static int i5400_probe1(struct pci_dev *pdev, int dev_idx)
 	if (i5400_init_dimms(mci)) {
 		edac_dbg(0, "MC: Setting mci->edac_cap to EDAC_FLAG_NONE because i5400_init_dimms() returned nonzero value\n");
 		mci->edac_cap = EDAC_FLAG_NONE;	/* no dimms found */
+		pvt->enabled_error_reporting = false;
 	} else {
 		edac_dbg(1, "MC: Enable error reporting now\n");
-		i5400_enable_error_reporting(mci);
+		i5400_set_error_reporting(mci, true);
+		pvt->enabled_error_reporting = true;
 	}
 
 	/* add this new MC control structure to EDAC's list of MCs */
 	if (edac_mc_add_mc(mci)) {
 		edac_dbg(0, "MC: failed edac_mc_add_mc()\n");
-		/* FIXME: perhaps some code should go here that disables error
-		 * reporting if we just enabled it
-		 */
+		/* Disable error reporting if we just enabled it */
+		if (pvt->enabled_error_reporting)
+			i5400_set_error_reporting(mci, false);
 		goto fail1;
 	}
 
@@ -1387,6 +1395,7 @@ static int i5400_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
 static void i5400_remove_one(struct pci_dev *pdev)
 {
 	struct mem_ctl_info *mci;
+	struct i5400_pvt *pvt;
 
 	edac_dbg(0, "\n");
 
@@ -1397,6 +1406,12 @@ static void i5400_remove_one(struct pci_dev *pdev)
 	if (!mci)
 		return;
 
+	pvt = mci->pvt_info;
+
+	/* Disable error reporting on teardown */
+	if (pvt->enabled_error_reporting)
+		i5400_set_error_reporting(mci, false);
+
 	/* retrieve references to resources, and free those resources */
 	i5400_put_devices(mci);
 
-- 
2.43.0