diff options
Diffstat (limited to 'drivers/staging/greybus/module.c')
| -rw-r--r-- | drivers/staging/greybus/module.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/drivers/staging/greybus/module.c b/drivers/staging/greybus/module.c index 5077253037c8..ea5895475181 100644 --- a/drivers/staging/greybus/module.c +++ b/drivers/staging/greybus/module.c @@ -138,13 +138,32 @@ static void gb_module_register_interface(struct gb_interface *intf) struct gb_module *module = intf->module; u8 intf_id = intf->interface_id; int ret; + int retries = 3; mutex_lock(&intf->mutex); - ret = gb_interface_activate(intf); + while (retries--) { + ret = gb_interface_activate(intf); + if (ret != -EAGAIN) + break; + } if (ret) { dev_err(&module->dev, "failed to activate interface %u: %d\n", intf_id, ret); + + /* + * -EAGAIN indicates that the Greybus operation + * interface_activate determined the remote interface to be + * UniPro-only. At present, we assume a UniPro-only module + * to be a Greybus module that failed to send its mailbox + * poke. There is some reason to believe that this is + * because of a bug in the ES3 bootrom. If we exhause our + * retries trying to activate such an interface, convert + * the error code back into a "no device" error. + */ + if (ret == -EAGAIN) + ret = -ENODEV; + gb_interface_add(intf); goto err_unlock; } |