firmware: microchip: auto-update: fix poll_complete() to not report spurious timeout...

fw_upload's poll_complete() is really intended for use with
asynchronous write() implementations - or at least those where the
write() loop may terminate without the kernel yet being aware of whether
or not the firmware upload has succeeded. For auto-update, write() is
only ever called once and will only return when uploading has completed,
be that by passing or failing. The core fw_upload code only calls
poll_complete() after the final call to write() has returned.

However, the poll_complete() implementation in the auto-update driver
was written to expect poll_complete() to be called from another context,
and it waits for a completion signalled from write(). Since
poll_complete() is actually called from the same context, after the
write() loop has terminated, wait_for_completion() never sees the
completion get signalled and always times out, causing programming to
always report a failing.

Since write() is full synchronous, and its return value will indicate
whether or not programming passed or failed, poll_complete() serves no
purpose and can be cut down to simply return FW_UPLOAD_ERR_NONE.

Cc: stable@vger.kernel.org
Fixes: ec5b0f1193ad4 ("firmware: microchip: add PolarFire SoC Auto Update support")
Reported-by: Jamie Gibbons <jamie.gibbons@microchip.com>
Tested-by: Jamie Gibbons <jamie.gibbons@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>

diff --git a/drivers/firmware/microchip/mpfs-auto-update.c b/drivers/firmware/microchip/mpfs-auto-update.c
index 9ca5ee5..0f7ec88 100644 (file)
--- a/drivers/firmware/microchip/mpfs-auto-update.c
+++ b/drivers/firmware/microchip/mpfs-auto-update.c
@@ -76,14 +76,11 @@
 #define AUTO_UPDATE_INFO_SIZE          SZ_1M
 #define AUTO_UPDATE_BITSTREAM_BASE     (AUTO_UPDATE_DIRECTORY_SIZE + AUTO_UPDATE_INFO_SIZE)
 
-#define AUTO_UPDATE_TIMEOUT_MS         60000
-
 struct mpfs_auto_update_priv {
        struct mpfs_sys_controller *sys_controller;
        struct device *dev;
        struct mtd_info *flash;
        struct fw_upload *fw_uploader;
-       struct completion programming_complete;
        size_t size_per_bitstream;
        bool cancel_request;
 };
@@ -156,19 +153,6 @@ static void mpfs_auto_update_cancel(struct fw_upload *fw_uploader)
 
 static enum fw_upload_err mpfs_auto_update_poll_complete(struct fw_upload *fw_uploader)
 {
-       struct mpfs_auto_update_priv *priv = fw_uploader->dd_handle;
-       int ret;
-
-       /*
-        * There is no meaningful way to get the status of the programming while
-        * it is in progress, so attempting anything other than waiting for it
-        * to complete would be misplaced.
-        */
-       ret = wait_for_completion_timeout(&priv->programming_complete,
-                                         msecs_to_jiffies(AUTO_UPDATE_TIMEOUT_MS));
-       if (!ret)
-               return FW_UPLOAD_ERR_TIMEOUT;
-
        return FW_UPLOAD_ERR_NONE;
 }
 
@@ -349,33 +333,23 @@ static enum fw_upload_err mpfs_auto_update_write(struct fw_upload *fw_uploader,
                                                 u32 offset, u32 size, u32 *written)
 {
        struct mpfs_auto_update_priv *priv = fw_uploader->dd_handle;
-       enum fw_upload_err err = FW_UPLOAD_ERR_NONE;
        int ret;
 
-       reinit_completion(&priv->programming_complete);
-
        ret = mpfs_auto_update_write_bitstream(fw_uploader, data, offset, size, written);
-       if (ret) {
-               err = FW_UPLOAD_ERR_RW_ERROR;
-               goto out;
-       }
+       if (ret)
+               return FW_UPLOAD_ERR_RW_ERROR;
 
-       if (priv->cancel_request) {
-               err = FW_UPLOAD_ERR_CANCELED;
-               goto out;
-       }
+       if (priv->cancel_request)
+               return FW_UPLOAD_ERR_CANCELED;
 
        if (mpfs_auto_update_is_bitstream_info(data, size))
-               goto out;
+               return FW_UPLOAD_ERR_NONE;
 
        ret = mpfs_auto_update_verify_image(fw_uploader);
        if (ret)
-               err = FW_UPLOAD_ERR_FW_INVALID;
+               return FW_UPLOAD_ERR_FW_INVALID;
 
-out:
-       complete(&priv->programming_complete);
-
-       return err;
+       return FW_UPLOAD_ERR_NONE;
 }
 
 static const struct fw_upload_ops mpfs_auto_update_ops = {
@@ -461,8 +435,6 @@ static int mpfs_auto_update_probe(struct platform_device *pdev)
                return dev_err_probe(dev, ret,
                                     "The current bitstream does not support auto-update\n");
 
-       init_completion(&priv->programming_complete);
-
        fw_uploader = firmware_upload_register(THIS_MODULE, dev, "mpfs-auto-update",
                                               &mpfs_auto_update_ops, priv);
        if (IS_ERR(fw_uploader))