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Subject: Re: [PATCH] dmaengine: ti: omap-dma: Configure LCH_TYPE for OMAP1
To:     Russell King - ARM Linux <linux@armlinux.org.uk>,
        Aaro Koskinen <aaro.koskinen@iki.fi>
CC:     <vkoul@kernel.org>, <dan.j.williams@intel.com>,
        <dmaengine@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <tony@atomide.com>, <linux-omap@vger.kernel.org>
References: <20181119104040.12885-1-peter.ujfalusi@ti.com>
 <20181119184649.GE16897@darkstar.musicnaut.iki.fi>
 <6af8c6e7-bf5c-5555-161b-5d3fb7ecae43@ti.com>
 <20181120210406.GB24888@darkstar.musicnaut.iki.fi>
 <20181122102948.GN6920@n2100.armlinux.org.uk>
From:   Peter Ujfalusi <peter.ujfalusi@ti.com>
Message-ID: <6dbb56e9-f76b-5343-1c40-87f326fe06a7@ti.com>
Date:   Fri, 23 Nov 2018 13:49:26 +0200
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On 22/11/2018 12.29, Russell King - ARM Linux wrote:
> On Tue, Nov 20, 2018 at 11:04:06PM +0200, Aaro Koskinen wrote:
>> I had switched to PIO mode in 2015 since the WARNs about legacy DMA
>> API were too annoying and flooding the console. And now that I tried
>> using DMA again with g_ether, it doesn't work anymore. The device get's
>> recognized on host side, but no traffic goes through. Switching back to
>> PIO makes it to work again.
> 
> A solution to that would be to do what the warning message says, and
> update the driver to the DMAengine API.

Yep, omap_udc is the last user of legacy omap_dma API. It is a slow
progress as I do the conversion in my free time, onenand/omap2 and tusb
was converted not too long ago, let's see how the omap_udc is going to go.

> The reason it didn't get updated when the DMAengine conversion happened
> is because I don't have hardware for it, so had no way to test, and no
> one seemed to know that anyone was using it.  Eventually, the WARN_ON()
> was added to try and root out any users and generate interest in
> updating the drivers.  Obviously that didn't happen, because people
> just worked around the warning rather than saying anything.
> 
> I'm afraid we're long past the time that I'd be willing to update the
> omap_udc driver now as I've dropped most of my knowledge on that as
> it's been four years, and Peter has been looking after OMAP DMAengine
> issues since.
> 
> Sorry.
> 

- Péter

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