File 0052-capemgr-Implement-disable-overrides-on-the-cmd-line.patch of Package kernel-adaptation-bbb-v3.12

From ae6307333e0ba042056936086c9dfc6d424df193 Mon Sep 17 00:00:00 2001
From: Pantelis Antoniou <panto@antoniou-consulting.com>
Date: Mon, 1 Apr 2013 18:20:35 +0300
Subject: [PATCH 52/96] capemgr: Implement disable overrides on the cmd line

Allow capes to be disabled on the kernel command line.

Signed-off-by: Pantelis Antoniou <panto@antoniou-consulting.com>
---
 drivers/misc/cape/beaglebone/capemgr.c | 133 ++++++++++++++++++++++-----------
 1 file changed, 88 insertions(+), 45 deletions(-)

diff --git a/drivers/misc/cape/beaglebone/capemgr.c b/drivers/misc/cape/beaglebone/capemgr.c
index b22bf42..f1cedec 100644
--- a/drivers/misc/cape/beaglebone/capemgr.c
+++ b/drivers/misc/cape/beaglebone/capemgr.c
@@ -47,7 +47,14 @@
 /* extra command line overrides */
 static char *extra_override = NULL;
 module_param(extra_override, charp, 0444);
-MODULE_PARM_DESC(extra_override, "Comma delimited list of PART-NUMBER[:REV] overrides");
+MODULE_PARM_DESC(extra_override,
+		"Comma delimited list of PART-NUMBER[:REV] overrides");
+
+/* disabled capes */
+static char *disable_partno = NULL;
+module_param(disable_partno, charp, 0444);
+MODULE_PARM_DESC(disable_partno,
+		"Comma delimited list of PART-NUMBER[:REV] of disabled capes");
 
 struct bone_capemgr_info;
 
@@ -547,51 +554,19 @@ slot_fail_check:
 	return 0;
 }
 
-/* check an override slot node if it's compatible */
-static int bone_is_compatible_override(struct device_node *node,
-		const char *compatible_name)
+/* return 0 if not matched,, 1 if matched */
+static int bone_match_cape(const char *match,
+		const char *part_number, const char *version)
 {
-	struct property *prop;
-	char *buf, *s, *e, *sn;
-	const char *part_number;
-	const char *version;
 	char *tmp_part_number, *tmp_version;
+	char *buf, *s, *e, *sn;
 	int found;
 
-	/* check if the slot is compatible with the board */
-	prop = of_find_property(node, "compatible", NULL);
-
-	/* no prop, it's something that's compatible with everything */
-	if (prop == NULL)
-		return 1;
-
-	/* check if it's directly compatible with the baseboard */
-	if (of_multi_prop_cmp(prop, compatible_name) == 0)
-		return 1;
-
-	/* forced override? */
-	if (of_multi_prop_cmp(prop, "force") == 0)
-		return 1;
-
-	/* final try, check if it's specified in the kernel command line */
-	if (extra_override == NULL)
-		return 0;
-
-	/* the compatible name should have kernel-command-line in it */
-	if (of_multi_prop_cmp(prop, "kernel-command-line") != 0)
-		return 0;
-
-	/* we must have at least the part-name */
-	if (of_property_read_string(node, "part-number",
-				&part_number) != 0)
+	if (match == NULL || part_number == NULL)
 		return 0;
 
-	/* read the version (if it exists) */
-	if (of_property_read_string(node, "version", &version) != 0)
-		version = NULL;
-
 	/* copy the argument to work on it */
-	buf = kstrdup(extra_override, GFP_KERNEL);
+	buf = kstrdup(match, GFP_KERNEL);
 
 	/* no memory, too bad... */
 	if (buf == NULL)
@@ -617,12 +592,6 @@ static int bone_is_compatible_override(struct device_node *node,
 		if (strcmp(tmp_part_number, part_number) != 0)
 			continue;
 
-		pr_info("override: part-number='%s' version='%s' "
-				"tmp_version='%s'\n",
-				part_number,
-				version ? version : "N/A",
-				tmp_version ? tmp_version : "N/A");
-
 		/* if there's no version, match any */
 		if (version == NULL || tmp_version == NULL ||
 			strcmp(version, tmp_version) == 0) {
@@ -636,6 +605,50 @@ static int bone_is_compatible_override(struct device_node *node,
 	return found;
 }
 
+/* check an override slot node if it's compatible */
+static int bone_is_compatible_override(struct device_node *node,
+		const char *compatible_name)
+{
+	struct property *prop;
+	const char *part_number;
+	const char *version;
+
+	/* check if the slot is compatible with the board */
+	prop = of_find_property(node, "compatible", NULL);
+
+	/* no prop, it's something that's compatible with everything */
+	if (prop == NULL)
+		return 1;
+
+	/* check if it's directly compatible with the baseboard */
+	if (of_multi_prop_cmp(prop, compatible_name) == 0)
+		return 1;
+
+	/* forced override? */
+	if (of_multi_prop_cmp(prop, "force") == 0)
+		return 1;
+
+	/* final try, check if it's specified in the kernel command line */
+	if (extra_override == NULL)
+		return 0;
+
+	/* the compatible name should have kernel-command-line in it */
+	if (of_multi_prop_cmp(prop, "kernel-command-line") != 0)
+		return 0;
+
+	/* we must have at least the part-name */
+	if (of_property_read_string(node, "part-number",
+				&part_number) != 0)
+		return 0;
+
+	/* read the version (if it exists) */
+	if (of_property_read_string(node, "version", &version) != 0)
+		version = NULL;
+
+	/* match on the extra override */
+	return bone_match_cape(extra_override, part_number, version);
+}
+
 static int bone_is_compatible_runtime_override(struct device_node *node,
 		const char *req_part_number, const char *req_version)
 {
@@ -1045,6 +1058,15 @@ found:
 						part_number, version))
 				continue;
 
+			/* if matches the disabled ones skip */
+			if (bone_match_cape(disable_partno,
+						part_number, NULL)) {
+				dev_info(&pdev->dev,
+					"Skipping disabled cape with "
+						"part# %s\n", part_number);
+				continue;
+			}
+
 			slot = bone_capemgr_add_slot(info, node,
 					part_number, version);
 			if (IS_ERR(slot)) {
@@ -1522,6 +1544,7 @@ bone_capemgr_add_slot(struct bone_capemgr_info *info, struct device_node *node,
 				slotno);
 		/* but all is fine */
 	} else {
+
 		dev_info(dev, "slot #%d: '%s'\n",
 				slotno, slot->text_id);
 
@@ -1701,6 +1724,15 @@ bone_capemgr_probe(struct platform_device *pdev)
 						&part_number) != 0)
 				continue;
 
+			/* if matches the disabled ones skip */
+			if (bone_match_cape(disable_partno,
+						part_number, NULL)) {
+				dev_info(&pdev->dev,
+					"Skipping disabled cape with "
+						"part# %s\n", part_number);
+				continue;
+			}
+
 			len = sizeof(*capemap) + strlen(part_number) + 1;
 			capemap = devm_kzalloc(&pdev->dev, len, GFP_KERNEL);
 			if (capemap == NULL) {
@@ -1741,6 +1773,7 @@ bone_capemgr_probe(struct platform_device *pdev)
 				ret = PTR_ERR(slot);
 				goto err_exit;
 			}
+			/* note that slot may be NULL (means it was disabled) */
 		}
 		of_node_put(slots_node);
 	}
@@ -1760,6 +1793,16 @@ bone_capemgr_probe(struct platform_device *pdev)
 	/* now load each (take lock to be sure */
 	mutex_lock(&info->slots_list_mutex);
 	list_for_each_entry(slot, &info->slot_list, node) {
+
+		/* if matches the disabled ones skip */
+		if (bone_match_cape(disable_partno,
+					slot->part_number, NULL)) {
+			dev_info(&pdev->dev,
+				"Skipping loading of disabled cape with "
+					"part# %s\n", slot->part_number);
+			continue;
+		}
+
 		if (!slot->probe_failed && !slot->loaded) {
 			slot->loading = 1;
 			slot->loader_thread = kthread_run(bone_capemgr_loader,
-- 
1.9.1