Return-path: Received: from smtp.ralinktech.com.tw ([211.75.121.152]:33608 "HELO smtp.ralinktech.com.tw" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751064Ab1BJFad convert rfc822-to-8bit (ORCPT ); Thu, 10 Feb 2011 00:30:33 -0500 From: RA-Jay Hung To: Ivo Van Doorn , Kalle Valo CC: "users@rt2x00.serialmonkey.com" , "linux-wireless@vger.kernel.org" , RA-Dennis Lee , RA-Eddy Tsai Subject: RE: [RFC] rt2x00: Add autowakeup timer for receiving beacons while in powersave mode Date: Thu, 10 Feb 2011 05:24:11 +0000 Message-ID: References: <201101311600.39486.IvDoorn@gmail.com> <874o8mbaec.fsf@purkki.adurom.net> In-Reply-To: Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: Hi Ivo, > Well the official Ralink driver also uses a timer to wakeup the hardware, > there are however registers which suggest support for autowake functionality. > Jay, Dennis, Eddy, can you explain a but how the autowake functionality is > implemented in the rt2800usb firmware? Current power saving and wake up procedure as below. PCI: 1. Driver sends power-save command to firmware to turn off RF/BBP and configure mac register (AUTO_WAKEUP_CFG) to set a hardware timer counter. 2. When hardware timer timeout, issue an interrupt and notify the driver. 3. Driver send wake up command to firmware to turn on RF/BBP and ready to process packets USB: 1. Driver sends power-save command to firmware to turn off RF/BBP and set a software timer to emulate the purpose of hardware timer. 2. When software timer timeout, driver sends wake up command to firmware to turn on RF/BBP and ready to process packets. Note: for future projects, hw or firmware will take more psm mechanism to reduce some latency between firmware and host to save more power. BR, Jay CONFIDENTIALITY STATEMENT : The information, attachments and any rights attaching in this e-mail are confidential and privileged; it is intended only for the individual or entity named as the recipient hereof.Any disclosure, copying, distribution, dissemination or use of the contents of this e-mail by persons other than the intended recipient is STRICTLY PROHIBITED and may violate applicable laws.If you have received this e-mail in error, please delete the original message and notify us by return email or collect call immediately. Thank you.