From mboxrd@z Thu Jan 1 00:00:00 1970 From: Neil Leeder Subject: Re: [PATCH v2] input: mouse: add qci touchpad driver Date: Fri, 13 Aug 2010 17:56:41 -0400 Message-ID: <4C65BF99.9030601@codeaurora.org> References: <1281631760-15589-1-git-send-email-nleeder@codeaurora.org> <4C642E6D.6000908@codeaurora.org> <4C64363A.4080406@codeaurora.org> <20100813024912.GA2661@core.coreip.homeip.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from wolverine01.qualcomm.com ([199.106.114.254]:38413 "EHLO wolverine01.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752903Ab0HMV4o (ORCPT ); Fri, 13 Aug 2010 17:56:44 -0400 In-Reply-To: <20100813024912.GA2661@core.coreip.homeip.net> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Dmitry Torokhov Cc: Stepan Moskovchenko , linux-input@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, Horace Fu , Mandeep Singh Baines , Trilok Soni On 8/12/2010 10:49 PM, Dmitry Torokhov wrote: > On Thu, Aug 12, 2010 at 01:58:18PM -0400, Neil Leeder wrote: > Actually, since this is not a new touchpad but simply a PS/2 interface > it should be implemented as a serio driver, not input device driver. > Dmitri, Thanks for supplying that serio driver. I just have a couple of questions. Even though the interface on the wpce775x EC happens to be a PS/2 interface, this is completely hidden by the firmware on that device. To the linux driver it looks like a dedicated i2c connection directly to the touchpad. You can't substitute any other device on that PS/2 interface without rewriting the firmware in the EC - it's not a generic interface. A manufacturer could even move the touchpad from the PS/2 interface to say GPIOs, re-write the firmware and the linux driver couldn't tell the difference. Does that change the rationale for using a serio driver? If the request to use a serio driver is still valid, then it seems that the workqueue from the interrupt handler sends each byte of data received over i2c in a separate serio_interrupt() call to the touchpad driver. Touchpad data comes in 3-byte packets, so the touchpad driver will have to re-assemble the packet from 3 separate interrupts. Is that the intended use? > Could you please tell me if the following works for you? Note that it > expects IRQ to be set up properly (edge vs. level trigger) by the > platform code The i2c_board_info that supplies the irq # from platform code doesn't have a way to set i2c flags, and can't set_irq_type() until after irq_request(). This may require another platform_data struct to pass the trigger level in. Thanks. -- Neil -- Sent by an employee of the Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.