Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751653AbdG0POj (ORCPT ); Thu, 27 Jul 2017 11:14:39 -0400 Received: from mail-wr0-f173.google.com ([209.85.128.173]:36484 "EHLO mail-wr0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751582AbdG0POh (ORCPT ); Thu, 27 Jul 2017 11:14:37 -0400 Subject: Re: [PATCH v2 1/2] platform: Add Amlogic Meson AO CEC Controller driver From: Neil Armstrong To: Hans Verkuil , mchehab@kernel.org, hans.verkuil@cisco.com Cc: linux-media@vger.kernel.org, linux-amlogic@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <1499673696-21372-1-git-send-email-narmstrong@baylibre.com> <1499673696-21372-2-git-send-email-narmstrong@baylibre.com> <6f93edd0-098e-6cbc-9eea-99dd68ab3420@xs4all.nl> <9acecab0-7dda-9aa1-fa07-886d40f6c7df@baylibre.com> Organization: Baylibre Message-ID: Date: Thu, 27 Jul 2017 17:14:32 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: <9acecab0-7dda-9aa1-fa07-886d40f6c7df@baylibre.com> Content-Type: text/plain; charset=windows-1252 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3388 Lines: 94 On 07/27/2017 04:43 PM, Neil Armstrong wrote: > On 07/25/2017 03:45 PM, Hans Verkuil wrote: >> On 07/25/17 14:34, Neil Armstrong wrote: >>> Hi Hans, >> >>>>> +static int meson_ao_cec_probe(struct platform_device *pdev) >>>>> +{ >>>>> + struct meson_ao_cec_device *ao_cec; >>>>> + struct platform_device *hdmi_dev; >>>>> + struct device_node *np; >>>>> + struct resource *res; >>>>> + int ret, irq; >>>>> + >>>>> + np = of_parse_phandle(pdev->dev.of_node, "hdmi-phandle", 0); >>>>> + if (!np) { >>>>> + dev_err(&pdev->dev, "Failed to find hdmi node\n"); >>>>> + return -ENODEV; >>>>> + } >>>>> + >>>>> + hdmi_dev = of_find_device_by_node(np); >>>>> + if (hdmi_dev == NULL) >>>>> + return -EPROBE_DEFER; >>>>> + >>>>> + ao_cec = devm_kzalloc(&pdev->dev, sizeof(*ao_cec), GFP_KERNEL); >>>>> + if (!ao_cec) >>>>> + return -ENOMEM; >>>>> + >>>>> + spin_lock_init(&ao_cec->cec_reg_lock); >>>>> + >>>>> + ao_cec->notify = cec_notifier_get(&hdmi_dev->dev); >>>>> + if (!ao_cec->notify) >>>>> + return -ENOMEM; >>>>> + >>>>> + ao_cec->adap = cec_allocate_adapter(&meson_ao_cec_ops, ao_cec, >>>>> + "meson_ao_cec", >>>>> + CEC_CAP_LOG_ADDRS | >>>>> + CEC_CAP_TRANSMIT | >>>>> + CEC_CAP_RC | >>>>> + CEC_CAP_PASSTHROUGH, >>>>> + 1); /* Use 1 for now */ >>>> >>>> I recommend that you add support for 2 logical addresses. More isn't allowed >>>> by the CEC 2.0 spec anyway (no such restriction for CEC 1.4, but more than >>>> two really isn't needed). >>> >>> I know, but in the "communication" register with the suspend/poweroff firmware >>> that handles the wake up, only a single logical address is supported... >>> >>> What should I do in this case ? Which logical adress should I pass to the firmware when implementing ir ? >> >> Ah, OK. Interesting. >> >> From cec-adap.c: >> >> if (log_addrs->num_log_addrs == 2) { >> if (!(type_mask & ((1 << CEC_LOG_ADDR_TYPE_AUDIOSYSTEM) | >> (1 << CEC_LOG_ADDR_TYPE_TV)))) { >> dprintk(1, "two LAs is only allowed for audiosystem and TV\n"); >> return -EINVAL; >> } >> if (!(type_mask & ((1 << CEC_LOG_ADDR_TYPE_PLAYBACK) | >> (1 << CEC_LOG_ADDR_TYPE_RECORD)))) { >> dprintk(1, "an audiosystem/TV can only be combined with record or playback\n"); >> return -EINVAL; >> } >> } >> >> So you would store the TV or AUDIOSYSTEM logical address in the firmware, since those >> describe the system best. >> >> I.e. it is a TV/Audiosystem with recording/playback capabilities. >> >> The problem is that for CEC 1.4 no such restriction is imposed (the test above is >> specific to CEC 2.0). But I think it makes sense to just check if TV/Audiosystem >> is selected and pick that as the LA to store in the firmware, and otherwise just >> pick the first LA (log_addr[0]). > > > Ok I'll add support for dual LA, and I'll do this LA selection when I'll add firmware support. Sorry, but having more than 1 LA makes the CEC controller very unstable, I'll need more info from amlogic to activate multiple LAs. Neil > > Thanks, > Neil > > >> Regards, >> >> Hans >> >