From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mailrelay005.isp.belgacom.be (mailrelay005.isp.belgacom.be [195.238.6.171]) by ozlabs.org (Postfix) with ESMTP id 3E8A7DE33B for ; Tue, 15 Apr 2008 23:32:29 +1000 (EST) Received: from smtp.belgium.cse-semaphore.com (localhost [127.0.0.1]) by smtp.belgium.cse-semaphore.com (Postfix) with ESMTP id BA78DBC28 for ; Tue, 15 Apr 2008 15:32:27 +0200 (CEST) Received: from pclaurent.belgium.cse-semaphore.com (pclaurent.belgium.cse-semaphore.com [192.168.1.47]) by smtp.belgium.cse-semaphore.com (Postfix) with ESMTP id A03BB997E for ; Tue, 15 Apr 2008 15:32:27 +0200 (CEST) From: Laurent Pinchart To: linuxppc-dev@ozlabs.org Subject: [RFC] Using two baud rate generators with the cpm_uart driver Date: Tue, 15 Apr 2008 15:32:26 +0200 MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart6107132.MQacW3snp2"; protocol="application/pgp-signature"; micalg=pgp-sha1 Message-Id: <200804151532.27057.laurentp@cse-semaphore.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , --nextPart6107132.MQacW3snp2 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Hi everybody, thanks to a bad hardware design decision, I'm faced with a software issue w= ith=20 the cpm_uart driver. My hardware uses either SCC4 or SMC2 (production-time option) as an RS485 p= ort=20 with an external transceiver. The transceiver's data direction is controlle= d=20 by external logic that monitors the SCC4/SMC2 TxD signal. The external logic needs an input clock at the baud rate frequency on the=20 MPC8248 BRG5 output pin (although I could modify it to accept an input cloc= k=20 at 16x the baud rate frequency). This means the cpm_uart driver has to setu= p=20 two baud rate generators instead of one. The ppc architecture was easy to hack as it used a fs_uart_platform_info=20 structure in which I added a set_brg function pointer provided by platform= =20 code. This isn't possible with the powerpc architecture anymore. Is there a clean way to fix this issue ? Kicking the hardware designer won'= t=20 help :-) Best regards, =2D-=20 Laurent Pinchart CSE Semaphore Belgium Chaussee de Bruxelles, 732A B-1410 Waterloo Belgium T +32 (2) 387 42 59 =46 +32 (2) 387 42 75 --nextPart6107132.MQacW3snp2 Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (GNU/Linux) iD8DBQBIBK5r8y9gWxC9vpcRAjteAKDHcQ6YUmHYaD0aZzUJDRKiEUjEjACeJ+0E YaJUbYVgxXvpk2eVOQ2h2xo= =RZnU -----END PGP SIGNATURE----- --nextPart6107132.MQacW3snp2--