[PATCH 6.12 178/242] firmware: microchip: fail auto-update probe if no flash found

Greg Kroah-Hartman
2026-04-08T18:48:22Z

From: Conor Dooley <conor.dooley@microchip.com>

commit c7596f9001e2b83293e3658e4e1addde69bb335d upstream.

There's no point letting the driver probe if there is no flash, as
trying to do a firmware upload will fail. Move the code that attempts
to get the flash from firmware upload to probe, and let it emit a
message to users stating why auto-update is not supported.
The code currently could have a problem if there's a flash in
devicetree, but the system controller driver fails to get a pointer to
it from the mtd subsystem, which will cause
mpfs_sys_controller_get_flash() to return an error. Check for errors and
null, instead of just null, in the new clause.

CC: stable@vger.kernel.org
Fixes: ec5b0f1193ad4 ("firmware: microchip: add PolarFire SoC Auto Update support")
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/firmware/microchip/mpfs-auto-update.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

--- a/drivers/firmware/microchip/mpfs-auto-update.c
+++ b/drivers/firmware/microchip/mpfs-auto-update.c
@@ -113,10 +113,6 @@ static enum fw_upload_err mpfs_auto_upda
* be added here.
*/

- priv->flash = mpfs_sys_controller_get_flash(priv->sys_controller);
- if (!priv->flash)
- return FW_UPLOAD_ERR_HW_ERROR;
-
erase_size = round_up(erase_size, (u64)priv->flash->erasesize);

/*
@@ -427,6 +423,12 @@ static int mpfs_auto_update_probe(struct
return dev_err_probe(dev, PTR_ERR(priv->sys_controller),
"Could not register as a sub device of the system controller\n");

+ priv->flash = mpfs_sys_controller_get_flash(priv->sys_controller);
+ if (IS_ERR_OR_NULL(priv->flash)) {
+ dev_dbg(dev, "No flash connected to the system controller, auto-update not supported\n");
+ return -ENODEV;
+ }
+
priv->dev = dev;
platform_set_drvdata(pdev, priv);