[PATCH] mtd: rawnand: gpmi: add debugfs entry for BCH geometry

[han.xu@oss.nxp.com]

From: Han Xu <han.xu@nxp.com>

Export the BCH geometry parameters via debugfs to aid debugging and
provide the necessary information for legacy kobs-ng tool. The debugfs
directory "gpmi-nand" is created under the root debugfs tree, exposing:

bch_geometry  - blob containing the struct bch_geometry fields
raw_mode      - flag indicating raw mode status

The implementation is guarded with #ifdef CONFIG_DEBUG_FS to avoid
build failures when debugfs is disabled.

Signed-off-by: Han Xu <han.xu@nxp.com>
---
 drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
index c1f766cb225aa..3ceb8df7f8f93 100644
--- a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
+++ b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
@@ -7,6 +7,7 @@
  */
 #include <linux/cleanup.h>
 #include <linux/clk.h>
+#include <linux/debugfs.h>
 #include <linux/delay.h>
 #include <linux/slab.h>
 #include <linux/sched/task_stack.h>
@@ -732,6 +733,26 @@ static int common_nfc_set_geometry(struct gpmi_nand_data *this)
 	return err;
 }
 
+#ifdef CONFIG_DEBUG_FS
+static struct debugfs_blob_wrapper dbg_bch_geo;
+static void bch_create_debugfs(struct gpmi_nand_data *this)
+{
+	struct bch_geometry *bch_geo = &this->bch_geometry;
+	struct dentry *dbg_root;
+
+	dbg_root = debugfs_create_dir("gpmi-nand", NULL);
+	dbg_bch_geo.data = (void *)bch_geo;
+	dbg_bch_geo.size = sizeof(struct bch_geometry);
+	debugfs_create_blob("bch_geometry", 0444, dbg_root, &dbg_bch_geo);
+	/* create raw mode flag */
+	debugfs_create_file_full("raw_mode", 0444, dbg_root, NULL, NULL, NULL);
+}
+#else
+static void bch_create_debugfs(struct gpmi_nand_data *this)
+{
+}
+#endif /* CONFIG_DEBUG_FS */
+
 /* Configures the geometry for BCH.  */
 static int bch_set_geometry(struct gpmi_nand_data *this)
 {
@@ -2282,6 +2303,9 @@ static int gpmi_init_last(struct gpmi_nand_data *this)
 	if (ret)
 		return ret;
 
+	/* save BCH geometry to debugfs if CONFIG_DEBUG_FS is enabled */
+	bch_create_debugfs(this);
+
 	/* Init the nand_ecc_ctrl{} */
 	ecc->read_page	= gpmi_ecc_read_page;
 	ecc->write_page	= gpmi_ecc_write_page;

---
base-commit: f97bdc8ec1dc7b33781a702eeba55326c206be56
change-id: 20260727-nand_debugfs-74d6d6ba52df

Best regards,
--  
Han Xu <han.xu@nxp.com>