diff --git a/drivers/platform/surface/aggregator/core.c b/drivers/platform/surface/aggregator/core.c index 9591a28bc38a9..4e2e70f4dcf51 100644 --- a/drivers/platform/surface/aggregator/core.c +++ b/drivers/platform/surface/aggregator/core.c @@ -623,8 +623,10 @@ static int ssam_serial_hub_probe(struct serdev_device *serdev) acpi_status astatus; int status; - if (gpiod_count(&serdev->dev, NULL) < 0) + if (gpiod_count(&serdev->dev, NULL) < 0) { + dev_err(&serdev->dev, "no GPIO found\n"); return -ENODEV; + } status = devm_acpi_dev_add_driver_gpios(&serdev->dev, ssam_acpi_gpios); if (status) @@ -637,21 +639,36 @@ static int ssam_serial_hub_probe(struct serdev_device *serdev) /* Initialize controller. */ status = ssam_controller_init(ctrl, serdev); - if (status) + if (status) { + dev_err_probe(&serdev->dev, status, + "failed to initialize ssam controller\n"); goto err_ctrl_init; + } ssam_controller_lock(ctrl); /* Set up serdev device. */ serdev_device_set_drvdata(serdev, ctrl); serdev_device_set_client_ops(serdev, &ssam_serdev_ops); + + /* The following step can fail when it's called too early before the + * underlying uart device is ready (in this case -ENXIO is returned). + * Instead of simply giving up and losing everything, we can defer + * the probing by returning -EPROBE_DEFER so that the kernel would be + * able to retry later. */ status = serdev_device_open(serdev); - if (status) + if (status == -ENXIO) + status = -EPROBE_DEFER; + if (status) { + dev_err_probe(&serdev->dev, status, + "failed to open serdev device\n"); goto err_devopen; + } astatus = ssam_serdev_setup_via_acpi(ssh->handle, serdev); if (ACPI_FAILURE(astatus)) { status = -ENXIO; + dev_err(&serdev->dev, "failed to setup serdev\n"); goto err_devinit; } @@ -667,16 +684,22 @@ static int ssam_serial_hub_probe(struct serdev_device *serdev) * states. */ status = ssam_log_firmware_version(ctrl); - if (status) + if (status) { + dev_err(&serdev->dev, "failed to get firmware version\n"); goto err_initrq; + } status = ssam_ctrl_notif_d0_entry(ctrl); - if (status) + if (status) { + dev_err(&serdev->dev, "failed to notify EC of entry of D0\n"); goto err_initrq; + } status = ssam_ctrl_notif_display_on(ctrl); - if (status) + if (status) { + dev_err(&serdev->dev, "failed to notify EC of display on\n"); goto err_initrq; + } status = sysfs_create_group(&serdev->dev.kobj, &ssam_sam_group); if (status) @@ -684,8 +707,10 @@ static int ssam_serial_hub_probe(struct serdev_device *serdev) /* Set up IRQ. */ status = ssam_irq_setup(ctrl); - if (status) + if (status) { + dev_err_probe(&serdev->dev, status, "failed to setup IRQ\n"); goto err_irq; + } /* Finally, set main controller reference. */ status = ssam_try_set_controller(ctrl);