From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755907AbcK2Cdv (ORCPT + 2 others); Mon, 28 Nov 2016 21:33:51 -0500 Received: from mail-pg0-f66.google.com ([74.125.83.66]:33177 "EHLO mail-pg0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751347AbcK2Cdn (ORCPT ); Mon, 28 Nov 2016 21:33:43 -0500 Subject: Re: [PATCH V12 1/1] usb:serial: Add Fintek F81532/534 driver To: Johan Hovold References: <1479101879-26128-1-git-send-email-hpeter+linux_kernel@gmail.com> <20161124150425.GA30963@localhost> Cc: gregkh@linuxfoundation.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, tom_tsai@fintek.com.tw, peter_hong@fintek.com.tw, "Ji-Ze Hong (Peter Hong)" From: "Ji-Ze Hong (Peter Hong)" Message-ID: Date: Tue, 29 Nov 2016 10:33:16 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.5.0 MIME-Version: 1.0 In-Reply-To: <20161124150425.GA30963@localhost> Content-Type: text/plain; charset=big5; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: Hi Johan, Johan Hovold ©ó 2016/11/24 ¤U¤È 11:04 ¼g¹D: > On Mon, Nov 14, 2016 at 01:37:59PM +0800, Ji-Ze Hong (Peter Hong) wrote: >> This driver is for Fintek F81532/F81534 USB to Serial Ports IC. >> + } >> + >> + if (size_bulk_out != F81534_WRITE_BUFFER_SIZE || >> + size_bulk_in != F81534_MAX_RECEIVE_BLOCK_SIZE) { >> + dev_err(dev, "%s: endpoints packet size not matched\n", >> + __func__); > > Similarly: "unsupported endpoint max packet size\n". > > But just to be clear: You do want to bail out if connected at full > speed? You could also ask usb-serial core to allocate large enough > buffers (e.g. by setting the bulk_out_size driver field) and the host > controller will handle partitioning. Yes, this product cannot run on USB full-speed currently due to the bulk-out endpoint design. It need use 512 bytes packet size to transmit 4 ports TX data, but USB Full-speed only provide 64 byte. The F81534 will treat the all bulk-out data as port 0 although the host will spilt 512byte to 8 x 64bytes packets. -- With Best Regards, Peter Hong