mtd: s3c2410: make ecc mode configurable via platform data

Removing CONFIG_MTD_NAND_S3C2410_HWECC option and adding a ecc_mode
field in the drivers's platform data structure so it can be selectable
via platform data.

Also setting this field to NAND_ECC_SOFT in all boards using this
driver since none of them had CONFIG_MTD_NAND_S3C2410_HWECC enabled.
Signed-off-by: Sergio Prado <sergio.prado@e-labworks.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

arch/arm/mach-s3c24xx/common-smdk.c

@@ -171,6 +171,7 @@ static struct s3c2410_platform_nand smdk_nand_info = {
 	.twrph1		= 20,
 	.nr_sets	= ARRAY_SIZE(smdk_nand_sets),
 	.sets		= smdk_nand_sets,
+	.ecc_mode       = NAND_ECC_SOFT,
 };
 
 /* devices we initialise */

arch/arm/mach-s3c24xx/mach-anubis.c

@@ -223,6 +223,7 @@ static struct s3c2410_platform_nand __initdata anubis_nand_info = {
 	.nr_sets	= ARRAY_SIZE(anubis_nand_sets),
 	.sets		= anubis_nand_sets,
 	.select_chip	= anubis_nand_select,
+	.ecc_mode       = NAND_ECC_SOFT,
 };
 
 /* IDE channels */

arch/arm/mach-s3c24xx/mach-at2440evb.c

@@ -114,6 +114,7 @@ static struct s3c2410_platform_nand __initdata at2440evb_nand_info = {
 	.twrph1		= 40,
 	.nr_sets	= ARRAY_SIZE(at2440evb_nand_sets),
 	.sets		= at2440evb_nand_sets,
+	.ecc_mode       = NAND_ECC_SOFT,
 };
 
 /* DM9000AEP 10/100 ethernet controller */

arch/arm/mach-s3c24xx/mach-bast.c

@@ -299,6 +299,7 @@ static struct s3c2410_platform_nand __initdata bast_nand_info = {
 	.nr_sets	= ARRAY_SIZE(bast_nand_sets),
 	.sets		= bast_nand_sets,
 	.select_chip	= bast_nand_select,
+	.ecc_mode       = NAND_ECC_SOFT,
 };
 
 /* DM9000 */

arch/arm/mach-s3c24xx/mach-gta02.c

@@ -443,6 +443,7 @@ static struct s3c2410_platform_nand __initdata gta02_nand_info = {
 	.twrph1		= 15,
 	.nr_sets	= ARRAY_SIZE(gta02_nand_sets),
 	.sets		= gta02_nand_sets,
+	.ecc_mode       = NAND_ECC_SOFT,
 };
 
 

arch/arm/mach-s3c24xx/mach-jive.c

@@ -232,6 +232,7 @@ static struct s3c2410_platform_nand __initdata jive_nand_info = {
 	.twrph1		= 40,
 	.sets		= jive_nand_sets,
 	.nr_sets	= ARRAY_SIZE(jive_nand_sets),
+	.ecc_mode       = NAND_ECC_SOFT,
 };
 
 static int __init jive_mtdset(char *options)

arch/arm/mach-s3c24xx/mach-mini2440.c

@@ -287,6 +287,7 @@ static struct s3c2410_platform_nand mini2440_nand_info __initdata = {
 	.nr_sets	= ARRAY_SIZE(mini2440_nand_sets),
 	.sets		= mini2440_nand_sets,
 	.ignore_unset_ecc = 1,
+	.ecc_mode       = NAND_ECC_SOFT,
 };
 
 /* DM9000AEP 10/100 ethernet controller */

arch/arm/mach-s3c24xx/mach-osiris.c

@@ -238,6 +238,7 @@ static struct s3c2410_platform_nand __initdata osiris_nand_info = {
 	.nr_sets	= ARRAY_SIZE(osiris_nand_sets),
 	.sets		= osiris_nand_sets,
 	.select_chip	= osiris_nand_select,
+	.ecc_mode       = NAND_ECC_SOFT,
 };
 
 /* PCMCIA control and configuration */

arch/arm/mach-s3c24xx/mach-qt2410.c

@@ -284,6 +284,7 @@ static struct s3c2410_platform_nand __initdata qt2410_nand_info = {
 	.twrph1		= 20,
 	.nr_sets	= ARRAY_SIZE(qt2410_nand_sets),
 	.sets		= qt2410_nand_sets,
+	.ecc_mode       = NAND_ECC_SOFT,
 };
 
 /* UDC */

arch/arm/mach-s3c24xx/mach-rx1950.c

@@ -611,6 +611,7 @@ static struct s3c2410_platform_nand rx1950_nand_info = {
 	.twrph1 = 15,
 	.nr_sets = ARRAY_SIZE(rx1950_nand_sets),
 	.sets = rx1950_nand_sets,
+	.ecc_mode = NAND_ECC_SOFT,
 };
 
 static struct s3c2410_udc_mach_info rx1950_udc_cfg __initdata = {

arch/arm/mach-s3c24xx/mach-rx3715.c

@@ -164,6 +164,7 @@ static struct s3c2410_platform_nand __initdata rx3715_nand_info = {
 	.twrph1		= 15,
 	.nr_sets	= ARRAY_SIZE(rx3715_nand_sets),
 	.sets		= rx3715_nand_sets,
+	.ecc_mode       = NAND_ECC_SOFT,
 };
 
 static struct platform_device *rx3715_devices[] __initdata = {

arch/arm/mach-s3c24xx/mach-vstms.c

@@ -117,6 +117,7 @@ static struct s3c2410_platform_nand __initdata vstms_nand_info = {
 	.twrph1		= 20,
 	.nr_sets	= ARRAY_SIZE(vstms_nand_sets),
 	.sets		= vstms_nand_sets,
+	.ecc_mode       = NAND_ECC_SOFT,
 };
 
 static struct platform_device *vstms_devices[] __initdata = {

arch/arm/mach-s3c64xx/mach-hmt.c

@@ -204,6 +204,7 @@ static struct s3c2410_platform_nand hmt_nand_info = {
 	.twrph1		= 40,
 	.nr_sets	= ARRAY_SIZE(hmt_nand_sets),
 	.sets		= hmt_nand_sets,
+	.ecc_mode       = NAND_ECC_SOFT,
 };
 
 static struct gpio_led hmt_leds[] = {

arch/arm/mach-s3c64xx/mach-mini6410.c

@@ -142,6 +142,7 @@ static struct s3c2410_platform_nand mini6410_nand_info = {
 	.twrph1		= 40,
 	.nr_sets	= ARRAY_SIZE(mini6410_nand_sets),
 	.sets		= mini6410_nand_sets,
+	.ecc_mode       = NAND_ECC_SOFT,
 };
 
 static struct s3c_fb_pd_win mini6410_lcd_type0_fb_win = {

arch/arm/mach-s3c64xx/mach-real6410.c

@@ -194,6 +194,7 @@ static struct s3c2410_platform_nand real6410_nand_info = {
 	.twrph1		= 40,
 	.nr_sets	= ARRAY_SIZE(real6410_nand_sets),
 	.sets		= real6410_nand_sets,
+	.ecc_mode       = NAND_ECC_SOFT,
 };
 
 static struct platform_device *real6410_devices[] __initdata = {

drivers/mtd/nand/Kconfig

@@ -179,15 +179,6 @@ config MTD_NAND_S3C2410_DEBUG
 	help
 	  Enable debugging of the S3C NAND driver
 
-config MTD_NAND_S3C2410_HWECC
-	bool "Samsung S3C NAND Hardware ECC"
-	depends on MTD_NAND_S3C2410
-	help
-	  Enable the use of the controller's internal ECC generator when
-	  using NAND. Early versions of the chips have had problems with
-	  incorrect ECC generation, and if using these, the default of
-	  software ECC is preferable.
-
 config MTD_NAND_NDFC
 	tristate "NDFC NanD Flash Controller"
 	depends on 4xx

drivers/mtd/nand/s3c2410.c

@@ -497,7 +497,6 @@ static int s3c2412_nand_devready(struct mtd_info *mtd)
 
 /* ECC handling functions */
 
-#ifdef CONFIG_MTD_NAND_S3C2410_HWECC
 static int s3c2410_nand_correct_data(struct mtd_info *mtd, u_char *dat,
 				     u_char *read_ecc, u_char *calc_ecc)
 {
@@ -649,7 +648,6 @@ static int s3c2440_nand_calculate_ecc(struct mtd_info *mtd, const u_char *dat,
 
 	return 0;
 }
-#endif
 
 /* over-ride the standard functions for a little more speed. We can
  * use read/write block to move the data buffers to/from the controller
@@ -858,50 +856,7 @@ static void s3c2410_nand_init_chip(struct s3c2410_nand_info *info,
 	nmtd->info	   = info;
 	nmtd->set	   = set;
 
-#ifdef CONFIG_MTD_NAND_S3C2410_HWECC
-	chip->ecc.calculate = s3c2410_nand_calculate_ecc;
-	chip->ecc.correct   = s3c2410_nand_correct_data;
-	chip->ecc.mode	    = NAND_ECC_HW;
-	chip->ecc.strength  = 1;
-
-	switch (info->cpu_type) {
-	case TYPE_S3C2410:
-		chip->ecc.hwctl	    = s3c2410_nand_enable_hwecc;
-		chip->ecc.calculate = s3c2410_nand_calculate_ecc;
-		break;
-
-	case TYPE_S3C2412:
-		chip->ecc.hwctl     = s3c2412_nand_enable_hwecc;
-		chip->ecc.calculate = s3c2412_nand_calculate_ecc;
-		break;
-
-	case TYPE_S3C2440:
-		chip->ecc.hwctl     = s3c2440_nand_enable_hwecc;
-		chip->ecc.calculate = s3c2440_nand_calculate_ecc;
-		break;
-	}
-#else
-	chip->ecc.mode	    = NAND_ECC_SOFT;
-	chip->ecc.algo	= NAND_ECC_HAMMING;
-#endif
-
-	if (set->disable_ecc)
-		chip->ecc.mode	= NAND_ECC_NONE;
-
-	switch (chip->ecc.mode) {
-	case NAND_ECC_NONE:
-		dev_info(info->device, "NAND ECC disabled\n");
-		break;
-	case NAND_ECC_SOFT:
-		dev_info(info->device, "NAND soft ECC\n");
-		break;
-	case NAND_ECC_HW:
-		dev_info(info->device, "NAND hardware ECC\n");
-		break;
-	default:
-		dev_info(info->device, "NAND ECC UNKNOWN\n");
-		break;
-	}
+	chip->ecc.mode = info->platform->ecc_mode;
 
 	/* If you use u-boot BBT creation code, specifying this flag will
 	 * let the kernel fish out the BBT from the NAND, and also skip the
@@ -923,28 +878,74 @@ static void s3c2410_nand_init_chip(struct s3c2410_nand_info *info,
  *
  * The internal state is currently limited to the ECC state information.
 */
-static void s3c2410_nand_update_chip(struct s3c2410_nand_info *info,
-				     struct s3c2410_nand_mtd *nmtd)
+static int s3c2410_nand_update_chip(struct s3c2410_nand_info *info,
+				    struct s3c2410_nand_mtd *nmtd)
 {
 	struct nand_chip *chip = &nmtd->chip;
 
-	dev_dbg(info->device, "chip %p => page shift %d\n",
-		chip, chip->page_shift);
+	switch (chip->ecc.mode) {
 
-	if (chip->ecc.mode != NAND_ECC_HW)
-		return;
+	case NAND_ECC_NONE:
+		dev_info(info->device, "ECC disabled\n");
+		break;
+
+	case NAND_ECC_SOFT:
+		/*
+		 * This driver expects Hamming based ECC when ecc_mode is set
+		 * to NAND_ECC_SOFT. Force ecc.algo to NAND_ECC_HAMMING to
+		 * avoid adding an extra ecc_algo field to
+		 * s3c2410_platform_nand.
+		 */
+		chip->ecc.algo = NAND_ECC_HAMMING;
+		dev_info(info->device, "soft ECC\n");
+		break;
+
+	case NAND_ECC_HW:
+		chip->ecc.calculate = s3c2410_nand_calculate_ecc;
+		chip->ecc.correct   = s3c2410_nand_correct_data;
+		chip->ecc.strength  = 1;
+
+		switch (info->cpu_type) {
+		case TYPE_S3C2410:
+			chip->ecc.hwctl	    = s3c2410_nand_enable_hwecc;
+			chip->ecc.calculate = s3c2410_nand_calculate_ecc;
+			break;
+
+		case TYPE_S3C2412:
+			chip->ecc.hwctl     = s3c2412_nand_enable_hwecc;
+			chip->ecc.calculate = s3c2412_nand_calculate_ecc;
+			break;
+
+		case TYPE_S3C2440:
+			chip->ecc.hwctl     = s3c2440_nand_enable_hwecc;
+			chip->ecc.calculate = s3c2440_nand_calculate_ecc;
+			break;
+		}
+
+		dev_dbg(info->device, "chip %p => page shift %d\n",
+			chip, chip->page_shift);
 
 		/* change the behaviour depending on whether we are using
 		 * the large or small page nand device */
+		if (chip->page_shift > 10) {
+			chip->ecc.size	    = 256;
+			chip->ecc.bytes	    = 3;
+		} else {
+			chip->ecc.size	    = 512;
+			chip->ecc.bytes	    = 3;
+			mtd_set_ooblayout(nand_to_mtd(chip),
+					  &s3c2410_ooblayout_ops);
+		}
 
-	if (chip->page_shift > 10) {
-		chip->ecc.size	    = 256;
-		chip->ecc.bytes	    = 3;
-	} else {
-		chip->ecc.size	    = 512;
-		chip->ecc.bytes	    = 3;
-		mtd_set_ooblayout(nand_to_mtd(chip), &s3c2410_ooblayout_ops);
+		dev_info(info->device, "hardware ECC\n");
+		break;
+
+	default:
+		dev_err(info->device, "invalid ECC mode!\n");
+		return -EINVAL;
 	}
+
+	return 0;
 }
 
 /* s3c24xx_nand_probe
@@ -1046,7 +1047,9 @@ static int s3c24xx_nand_probe(struct platform_device *pdev)
 						 NULL);
 
 		if (nmtd->scan_res == 0) {
-			s3c2410_nand_update_chip(info, nmtd);
+			err = s3c2410_nand_update_chip(info, nmtd);
+			if (err < 0)
+				goto exit_error;
 			nand_scan_tail(mtd);
 			s3c2410_nand_add_partition(info, nmtd, sets);
 		}

include/linux/platform_data/mtd-nand-s3c2410.h

@@ -12,9 +12,10 @@
 #ifndef __MTD_NAND_S3C2410_H
 #define __MTD_NAND_S3C2410_H
 
+#include <linux/mtd/nand.h>
+
 /**
  * struct s3c2410_nand_set - define a set of one or more nand chips
- * @disable_ecc:	Entirely disable ECC - Dangerous
  * @flash_bbt: 		Openmoko u-boot can create a Bad Block Table
  *			Setting this flag will allow the kernel to
  *			look for it at boot time and also skip the NAND
@@ -31,7 +32,6 @@
  * a warning at boot time.
  */
 struct s3c2410_nand_set {
-	unsigned int		disable_ecc:1;
 	unsigned int		flash_bbt:1;
 
 	unsigned int		options;
@@ -51,6 +51,8 @@ struct s3c2410_platform_nand {
 
 	unsigned int	ignore_unset_ecc:1;
 
+	nand_ecc_modes_t	ecc_mode;
+
 	int			nr_sets;
 	struct s3c2410_nand_set *sets;