[PATCH] dfu: mmc: Add support for exposing whole mmc device

[Marek Vasut]

Add support for exposing the whole mmc device by setting the 'size'
parameter to 0. This can be useful in case it is not clear what the
total device size is up front. Update the documentation accordingly.

Signed-off-by: Marek Vasut <marex at denx.de>
---
Cc: Lukasz Majewski <lukma at denx.de>
Cc: Mattijs Korpershoek <mkorpershoek at baylibre.com>
Cc: Tom Rini <trini at konsulko.com>
---
 doc/usage/dfu.rst     |  5 +++++
 drivers/dfu/dfu_mmc.c | 10 ++++++++++
 2 files changed, 15 insertions(+)

diff --git a/doc/usage/dfu.rst b/doc/usage/dfu.rst
index 68cacbbef66..8845a71df36 100644
--- a/doc/usage/dfu.rst
+++ b/doc/usage/dfu.rst
@@ -121,6 +121,11 @@ mmc
 
     with
 
+    offset
+        is the offset in the device (hexadecimal without "0x")
+    size
+        is the size of the access area (hexadecimal without "0x")
+        or 0 which means whole device
     partid
         being the GPT or DOS partition index,
     num
diff --git a/drivers/dfu/dfu_mmc.c b/drivers/dfu/dfu_mmc.c
index cdb3c18b01d..12c54e90ef7 100644
--- a/drivers/dfu/dfu_mmc.c
+++ b/drivers/dfu/dfu_mmc.c
@@ -386,6 +386,16 @@ int dfu_fill_entity_mmc(struct dfu_entity *dfu, char *devstr, char **argv, int a
 		dfu->data.mmc.lba_size		= third_arg;
 		dfu->data.mmc.lba_blk_size	= mmc->read_bl_len;
 
+		/*
+		 * In case the size is zero (i.e. mmc raw 0x10 0),
+		 * assume the user intends to use whole device.
+		 */
+		if (third_arg == 0) {
+			struct blk_desc *blk_dev = mmc_get_blk_desc(mmc);
+
+			dfu->data.mmc.lba_size = blk_dev->lba;
+		}
+
 		/*
 		 * Check for an extra entry at dfu_alt_info env variable
 		 * specifying the mmc HW defined partition number
-- 
2.42.0