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USB: serial: cp210x: Removing unncessary usb_reset_device on startup

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This `usb_reset_device` command has been around since the driver was
originally reverse engineered. It doesn't cause much issue on single
interface CP210x devices, but on the CP2105 and CP2108 with 2 and 4
interfaces respectively it will cause instability on enumeration and
delays enumeration noticably. There should be no reason to reset a device
at startup, per the CP210x AN571 spec.

Signed-off-by: Preston Fick <preston.fick@silabs.com>
Cc: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Preston Fick 2014-07-16 14:31:30 -05:00 committed by Greg Kroah-Hartman
parent ce21bfe603
commit 934ef5aca9
1 changed files with 0 additions and 3 deletions
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3
drivers/usb/serial/cp210x.c
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@ -856,9 +856,6 @@ static int cp210x_startup(struct usb_serial *serial)
struct usb_host_interface *cur_altsetting;
struct cp210x_serial_private *spriv;
/* cp210x buffers behave strangely unless device is reset */
usb_reset_device(serial->dev);
spriv = kzalloc(sizeof(*spriv), GFP_KERNEL);
if (!spriv)
return -ENOMEM;