[PATCH] dfu: Add option to skip empty pages when flashing UBI images to NAND

[Guillermo Rodríguez]

Add a new option to enable the DROP_FFS flag when flashing UBI images to
NAND in order to drop trailing all-0xff pages.

This is similar to the existing FASTBOOT_FLASH_NAND_TRIMFFS option.

Signed-off-by: Guillermo Rodriguez <guille.rodriguez at gmail.com>
Cc: Lukasz Majewski <lukma at denx.de>
---
 drivers/dfu/Kconfig    | 7 +++++++
 drivers/dfu/dfu_nand.c | 7 ++++++-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/dfu/Kconfig b/drivers/dfu/Kconfig
index 75fe0a12c6..5573f5e9cc 100644
--- a/drivers/dfu/Kconfig
+++ b/drivers/dfu/Kconfig
@@ -36,6 +36,13 @@ config DFU_NAND
 	  This option enables using DFU to read and write to NAND based
 	  storage.
 
+config DFU_NAND_TRIMFFS
+	bool "Skip empty pages when flashing UBI images to NAND"
+	depends on DFU_NAND
+	help
+	  When flashing UBI images to NAND, enable the DROP_FFS flag to drop
+	  trailing all-0xff pages.
+
 config DFU_RAM
 	bool "RAM back end for DFU"
 	help
diff --git a/drivers/dfu/dfu_nand.c b/drivers/dfu/dfu_nand.c
index b812a3dfb1..58b94348c9 100644
--- a/drivers/dfu/dfu_nand.c
+++ b/drivers/dfu/dfu_nand.c
@@ -50,6 +50,7 @@ static int nand_block_op(enum dfu_op op, struct dfu_entity *dfu,
 					 lim, buf);
 	} else {
 		nand_erase_options_t opts;
+		int write_flags = WITH_WR_VERIFY;
 
 		memset(&opts, 0, sizeof(opts));
 		opts.offset = start;
@@ -62,8 +63,12 @@ static int nand_block_op(enum dfu_op op, struct dfu_entity *dfu,
 		if (ret)
 			return ret;
 		/* then write */
+#ifdef CONFIG_DFU_NAND_TRIMFFS
+		if (dfu->data.nand.ubi)
+			write_flags |= WITH_DROP_FFS;
+#endif
 		ret = nand_write_skip_bad(mtd, start, &count, &actual,
-					  lim, buf, WITH_WR_VERIFY);
+					  lim, buf, write_flags);
 	}
 
 	if (ret != 0) {
-- 
2.21.0