From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout.perfora.net (mout.perfora.net [74.208.4.196]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 475AE1B85CA; Fri, 6 Sep 2024 18:39:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.208.4.196 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725647944; cv=none; b=g7pP+3Ko4jnPkfwCcFiJ7HnLvdOoLyGPqNwXUNd1vU+s90i/DUC3a+RQT92kTxYAeg1PcfLIb7CQ9zAdV0AW+7j+0XsEePigFXSZkTAhVA6RdrOnT+gFEAjkCY1ld/OpMGFEUgUcyBpfQZO6Rqew3xhIh5cdUVEmQgEyXwPWwOs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725647944; c=relaxed/simple; bh=yPsiablW7v2+Y/1/4kVxtqn8UUHXMty+93REfIQpSBQ=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=MM6DvaGP8S7lPGeBFO9tsSUkSd/UuAhi2RH71t7SHHzuY2qJ7KdmJT/XSp27h4Yc8eoCvkPst1dNi8efCfvPgPlBT4xFBPnPcTvsE96bBcqC8nexo1leYLcLAv7lxpoB0u3/HA9ZViBMGRvjJtTQ75e+pzjI0zWjv3LAgMzWSGg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=finest.io; spf=pass smtp.mailfrom=finest.io; dkim=pass (2048-bit key) header.d=finest.io header.i=parker@finest.io header.b=xLzbyESs; arc=none smtp.client-ip=74.208.4.196 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=finest.io Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=finest.io Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=finest.io header.i=parker@finest.io header.b="xLzbyESs" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=finest.io; s=s1-ionos; t=1725647933; x=1726252733; i=parker@finest.io; bh=XRDSTIIsV2NZmDdeOuh3im7vzjDEzcqFnqtO/PSkD5I=; h=X-UI-Sender-Class:Date:From:To:Cc:Subject:Message-ID:In-Reply-To: References:MIME-Version:Content-Type:Content-Transfer-Encoding:cc: content-transfer-encoding:content-type:date:from:message-id: mime-version:reply-to:subject:to; b=xLzbyESsukgkXcie6Q+n7AxrzZ3UgL9kAUfhFWoVj9VYaMe+MnCd4Rwhyayed2fI pCJx3QDGt4GAQlGtpYr3PejS/+jD2/tcg6vvCIF2ZW+eilu1YgqWGr7No1DegbZzm +6FX9duJP2oO1MO8LVNmtt6giGz0+79TVBwS+xFs1ZpUXt5LHQy7isUHyNTCb0RdH rqhas3p7wqsnPNmyPXGljKwRtUKwFxKs/PQS5jgOy4Sx+ARVJbSgzsxWdySbbsq7J XoAAM/qQlQibjA7mFM/BlBZjf9TtEv4Fres5hznxOrynp4nveAT16xo8XMg/zIpmK drn7vHJxW4nw6+M/ZQ== X-UI-Sender-Class: 55c96926-9e95-11ee-ae09-1f7a4046a0f6 Received: from SWDEV2.connecttech.local ([98.159.241.229]) by mrelay.perfora.net (mreueus003 [74.208.5.2]) with ESMTPSA (Nemesis) id 0MAxJS-1swZTN1Vi8-002Clm; Fri, 06 Sep 2024 20:38:53 +0200 Date: Fri, 6 Sep 2024 14:38:51 -0400 From: Parker Newman To: Andy Shevchenko Cc: Parker Newman , linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, Greg Kroah-Hartman , Jiri Slaby Subject: Re: [PATCH v2 00/13] serial: 8250_exar: Clean up the driver Message-ID: <20240906143851.21c97ef9@SWDEV2.connecttech.local> In-Reply-To: References: <20240503171917.2921250-1-andriy.shevchenko@linux.intel.com> <20240503143303.15bf82bc@SWDEV2.connecttech.local> <20240906095141.021318c8@SWDEV2.connecttech.local> <20240906103354.0bf5f3b7@SWDEV2.connecttech.local> Organization: Connect Tech Inc. X-Mailer: Claws Mail 3.17.5 (GTK+ 2.24.32; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:iQB6M/+7TyKL2ZDIrzuiacTNDI+h/vhjuz60c6EJtZ0f11tHZRx e6IHVpX0BKKu9uJOeMr2+6AbT/WiXWyz+A5aQGjzpgjLguJcLhBt7nxFOTpOXUEzc8Naq53 lB99kaG15QNNUnUDX2Y1hb3pWqOAy/JHyI9H+Hla++MtOaOk5oMEAlSrtqtMFHr+VDHjHb5 6tF/SsDQ9g5Z6xZW0nJqA== X-Spam-Flag: NO UI-OutboundReport: notjunk:1;M01:P0:crcRF3cpUJY=;EC2i0H+YJ512p8UG9eiHglZOkoi SNZYMtSpZS1oUA38Wq0GfHP8Y9+77E+1TUnZO8vOXkrEK9zvvj4ITr0TPyV+JBnNN1Necfw+r RdjwKl8aNxwTftDBaMADCa7j3vKrGalAfM+s/O82fgI9wTuBQbT13ij1V5D9ambPELw8Vnxix vRjXSnrqg+6L2X9kkPOxZgsnqrU8hCd2Hhx2YuS4yxxcbd+97Q6Vs1t7+/Y81KUqqKV7nsP+r UYEPGBEzfgOshs0RfauoZXOj55uQKG0ziYRNysN4kx2X8iCO34ZRpYE9BkeSZXXDDjZ0OBYXd KvxOV5VNs+bi8eaSNFIdlOAVGVfv/z1kEkbhU+YsnSe9Kw4XUftUUTYFod9CHmvliVSISkRi0 jKR43MejQW6g+ZzWG0KRgmdq3UCX6gfWbMbJxUYX5D28pY1rZ4lsf9TE8X8GuIu0PrcaQwV0i fQWVnU3UqOyXo4bQuDagt2LF3Ay75/1n/gf9bQBNdpf4zUkMZoe9urEnrI1UdUM4OuaJf+u4u F29ypmZX1lCHsqj1vtp2Wv/bVZw3RJthm0VTPwwgL1hBlkKyS2roYC2H1h7HKAuoIaqfV4MtY vBAB6LPjNs3rqBDfoW+qgp7H9fDih0oFY3jtAQzjp5lcQcgpNkIoEgfHbf6n1QPV3RASDCXuZ QgSZFSQ3Licp11gYB4+y2Qd1da+DrIyiys/5D6jv0iSiOrGx/AS+PzvDyermmzt+V6feEbrj+ tauLumOmUaIWA0Nw9zQj6PTe8hbePKxUQ== On Fri, 6 Sep 2024 17:42:26 +0300 Andy Shevchenko wrote: > On Fri, Sep 06, 2024 at 10:33:54AM -0400, Parker Newman wrote: > > On Fri, 6 Sep 2024 17:24:44 +0300 > > Andy Shevchenko wrote: > > > On Fri, Sep 06, 2024 at 09:51:41AM -0400, Parker Newman wrote: > > > > On Fri, 6 Sep 2024 15:46:51 +0300 > > > > Andy Shevchenko wrote: > > > > > On Fri, May 03, 2024 at 02:33:03PM -0400, Parker Newman wrote: > > ... > > > > > > Sorry for blast from the past, but I have some instersting infor= mation > > > > > for you. We now have spi-gpio and 93c46 eeprom drivers available= to be > > > > > used from others via software nodes, can you consider updating y= our code > > > > > to replace custom bitbanging along with r/w ops by the instantia= ting the > > > > > respective drivers? > > > > > > > > Hi Andy, > > > > The Exar UARTs don't actually use MPIO/GPIO for the EEPROM. > > > > They have a dedicated "EEPROM interface" which is accessed by the > > > > REGB (0x8E) register. It is a very simple bit-bang interface thoug= h, > > > > one bit per signal. > > > > > > > > I guess in theory I could either add GPIO wrapper to toggle these= bits > > > > and use the spi-gpio driver but I am not sure if that really impro= ves things? > > > > Maybe using the spi-bitbang driver directly is more appropriate? > > > > What do you think? > > > > > > Yes, spi-bitbang seems better in this case. > > > > I will try to make some time to implement this... Or if someone else f= rom the > > community wants to take this on in the mean time I am certainly happy = to test > > and help out! > > Sure, I shared this thought due to having lack of time to look myself, > but I prepared the above mentioned drivers to make them work in this cas= e. > (If you are curios, see the Git history for the last few releases with > --author=3D"Andy Shevchenko") > Looking into it a bit more I think we could just use the eeprom_93cx6 driver without any SPI layer. Just need to add simple register_read() and register_write() functions to read/write the REB register. That should be a pretty easy change to make, I can try to make that change soon unless anyone has any objections to that method? Thanks, Parker