From: Lothar Waßmann <LW@KARO-electronics.de>
Date: Tue, 29 Aug 2017 10:07:00 +0000 (+0200)
Subject: mtd: nand: complain loudly when chip->bits_per_cell is not correctly initialized
X-Git-Tag: KARO-TX6-2017-10-26~10
X-Git-Url: https://git.kernelconcepts.de/?p=karo-tx-linux.git;a=commitdiff_plain;h=47d2f3cc737ba183a27901faf4048f422aa7c010;hp=f8813c6431971322ef813b39bf41d21c7f40b9c7

mtd: nand: complain loudly when chip->bits_per_cell is not correctly initialized

chip->bits_per_cell which is used to determine the NAND cell type
(SLC/MLC) should always have a value != 0.
Complain loudly if the value is 0 in nand_is_slc() to catch use before
correct initialization.
---

diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index 5216d2eb2289..14761eb01e56 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -1246,6 +1246,8 @@ int onfi_init_data_interface(struct nand_chip *chip,
  */
 static inline bool nand_is_slc(struct nand_chip *chip)
 {
+	WARN(chip->bits_per_cell == 0,
+	     "chip->bits_per_cell is used uninitialized\n");
 	return chip->bits_per_cell == 1;
 }