From: Tony Lindgren <tony@xxxxxxxxxxx> We are missing pm_runtime_disable() in 2430 glue layer. Further, we only need to enable PM runtime and disable it on exit. With musb_core.c doing PM, the glue layer as a parent will always be active when musb_core.c is active. This fixes host enumeration issues with some devices as reported by Ladislav Michl <ladis@xxxxxxxxxxxxxx>. And holding an RPM reference while deregistering the child would lead to a crash in omap2430_runtime_suspend() which dereferences the now freed child's driver data on put as pointed out by Johan Hovold <johan@xxxxxxxxxx>: Unable to handle kernel paging request at virtual address 6b6b6f17 ... [<c05453d4>] (omap2430_runtime_suspend) from [<c0481410>] (pm_generic_runtime_suspend+0x3c/0x48) [<c0481410>] (pm_generic_runtime_suspend) from [<c0121028>] (_od_runtime_suspend+0x1c/0x30) [<c0121028>] (_od_runtime_suspend) from [<c04833b0>] (__rpm_callback+0x3c/0x70) [<c04833b0>] (__rpm_callback) from [<c0483414>] (rpm_callback+0x30/0x90) [<c0483414>] (rpm_callback) from [<c0483984>] (rpm_suspend+0x118/0x6b4) [<c0483984>] (rpm_suspend) from [<c04840f4>] (rpm_idle+0x104/0x440) [<c04840f4>] (rpm_idle) from [<c04844ac>] (__pm_runtime_idle+0x7c/0xb0) [<c04844ac>] (__pm_runtime_idle) from [<c0545458>] (omap2430_remove+0x38/0x58) [<c0545458>] (omap2430_remove) from [<c047b2bc>] (platform_drv_remove+0x34/0x4c) Note that if changes are needed to the autosuspend timeout, it should be done in musb_core.c. Reported-by: Ladislav Michl <ladis@xxxxxxxxxxxxxx> Fixes: 87326e858448 ("usb: musb: Remove extra PM runtime calls from 2430 glue layer") Tested-by: Ladislav Michl <ladis@xxxxxxxxxxxxxx> Reviewed-by: Johan Hovold <johan@xxxxxxxxxx> Tested-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx> Signed-off-by: Bin Liu <b-liu@xxxxxx> --- drivers/usb/musb/omap2430.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/drivers/usb/musb/omap2430.c b/drivers/usb/musb/omap2430.c index cc1225485509..e8be8e39ab8f 100644 --- a/drivers/usb/musb/omap2430.c +++ b/drivers/usb/musb/omap2430.c @@ -513,17 +513,18 @@ static int omap2430_probe(struct platform_device *pdev) } pm_runtime_enable(glue->dev); - pm_runtime_use_autosuspend(glue->dev); - pm_runtime_set_autosuspend_delay(glue->dev, 100); ret = platform_device_add(musb); if (ret) { dev_err(&pdev->dev, "failed to register musb device\n"); - goto err2; + goto err3; } return 0; +err3: + pm_runtime_disable(glue->dev); + err2: platform_device_put(musb); @@ -535,10 +536,7 @@ static int omap2430_remove(struct platform_device *pdev) { struct omap2430_glue *glue = platform_get_drvdata(pdev); - pm_runtime_get_sync(glue->dev); platform_device_unregister(glue->musb); - pm_runtime_put_sync(glue->dev); - pm_runtime_dont_use_autosuspend(glue->dev); pm_runtime_disable(glue->dev); return 0; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html