Re: [PATCH v3] usb: core: introduce per-port over-current counters

From: Greg KH
Date: Tue Mar 20 2018 - 04:34:13 EST


On Wed, Mar 14, 2018 at 10:51:09AM +0100, Richard Leitner wrote:
> From: Richard Leitner <richard.leitner@xxxxxxxxxxx>
>
> For some userspace applications information on the number of
> over-current conditions at specific USB hub ports is relevant.
>
> In our case we have a series of USB hardware (using the cp210x driver)
> which communicates using a proprietary protocol. These devices sometimes
> trigger an over-current situation on some hubs. In case of such an
> over-current situation the USB devices offer an interface for reducing
> the max used power. As these conditions are quite rare and imply
> performance reductions of the device we don't want to reduce the max
> power always.
>
> Therefore give user-space applications the possibility to react
> adequately by introducing an over_current_counter in the usb port struct
> which is exported via sysfs.
>
> Signed-off-by: Richard Leitner <richard.leitner@xxxxxxxxxxx>
> ---
> Documentation/ABI/testing/sysfs-bus-usb | 10 ++++++++++
> drivers/usb/core/hub.c | 4 +++-
> drivers/usb/core/hub.h | 1 +
> drivers/usb/core/port.c | 10 ++++++++++
> 4 files changed, 24 insertions(+), 1 deletion(-)

What changed from the previous versions? Always include that below the
--- line so we have an idea of what is going on here.

v4?

thanks,

greg k-h