From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sowjanya Komatineni Subject: Re: [PATCH v7 15/21] ASoC: tegra: Add fallback implementation for audio mclk Date: Fri, 10 Jan 2020 14:13:42 -0800 Message-ID: <575aa30e-1b5a-2a2d-5893-3f6832f416f1@nvidia.com> References: <1578457515-3477-1-git-send-email-skomatineni@nvidia.com> <1578457515-3477-16-git-send-email-skomatineni@nvidia.com> <745b8c7b-4fe3-c9ea-284e-b89546e8ad87@nvidia.com> <705edf9b-d1bc-8090-017e-fa4ad445f9fb@nvidia.com> <135f0c0b-86d1-9b1a-af02-c14c4b5308c4@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <135f0c0b-86d1-9b1a-af02-c14c4b5308c4@gmail.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Dmitry Osipenko , Sameer Pujar , thierry.reding@gmail.com, jonathanh@nvidia.com, broonie@kernel.org, lgirdwood@gmail.com, perex@perex.cz, tiwai@suse.com, mperttunen@nvidia.com, gregkh@linuxfoundation.org, sboyd@kernel.org, robh+dt@kernel.org, mark.rutland@arm.com Cc: pdeschrijver@nvidia.com, pgaikwad@nvidia.com, josephl@nvidia.com, daniel.lezcano@linaro.org, mmaddireddy@nvidia.com, markz@nvidia.com, devicetree@vger.kernel.org, linux-clk@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-tegra@vger.kernel.org On 1/10/20 2:05 PM, Dmitry Osipenko wrote: > External email: Use caution opening links or attachments > > > 10.01.2020 20:04, Sowjanya Komatineni =D0=BF=D0=B8=D1=88=D0=B5=D1=82: >> On 1/9/20 10:52 AM, Sowjanya Komatineni wrote: >>> >>> On 1/7/20 10:28 PM, Sameer Pujar wrote: >>>> On 1/8/2020 11:18 AM, Sowjanya Komatineni wrote: >>>>> On 1/7/20 9:34 PM, Sameer Pujar wrote: >>>>>> On 1/8/2020 9:55 AM, Sowjanya Komatineni wrote: >>>>>>> mclk is from clk_out_1 which is part of Tegra PMC block and pmc >>>>>>> clocks >>>>>>> are moved to Tegra PMC driver with pmc as clock provider and using >>>>>>> pmc >>>>>>> clock ids. >>>>>>> >>>>>>> New device tree uses clk_out_1 from pmc clock provider. >>>>>>> >>>>>>> So, this patch adds implementation for mclk fallback to extern1 whe= n >>>>>>> retrieving mclk returns -ENOENT to be backward compatible of new >>>>>>> device >>>>>>> tree with older kernels. >>>>>>> >>>>>>> Tested-by: Dmitry Osipenko >>>>>>> Reviewed-by: Dmitry Osipenko >>>>>>> Signed-off-by: Sowjanya Komatineni >>>>>>> --- >>>>>>> sound/soc/tegra/tegra_asoc_utils.c | 11 ++++++++++- >>>>>>> 1 file changed, 10 insertions(+), 1 deletion(-) >>>>>>> >>>>>>> diff --git a/sound/soc/tegra/tegra_asoc_utils.c >>>>>>> b/sound/soc/tegra/tegra_asoc_utils.c >>>>>>> index 9cfebef74870..9a5f81039491 100644 >>>>>>> --- a/sound/soc/tegra/tegra_asoc_utils.c >>>>>>> +++ b/sound/soc/tegra/tegra_asoc_utils.c >>>>>>> @@ -183,7 +183,16 @@ int tegra_asoc_utils_init(struct >>>>>>> tegra_asoc_utils_data *data, >>>>>>> data->clk_cdev1 =3D devm_clk_get(dev, "mclk"); >>>>>>> if (IS_ERR(data->clk_cdev1)) { >>>>>>> dev_err(data->dev, "Can't retrieve clk cdev1\n"); >>>>>> This error print can be moved inside below if, when this actually >>>>>> meant to be an error condition. >>>>>> >>>>> Want to show error even if mclk retrieval returns ENOENT to clearly >>>>> indicate mclk does not exist along with message of falling back to >>>>> extern1. >>>> Yes, but falling back essentially means 'mclk' is not available and >>>> fallback print is not an error. >>>> Not a major issue though, you can consider updating. Otherwise LGTM. >>>> >>> Will update >>>>>>> - return PTR_ERR(data->clk_cdev1); >>>>>>> + if (PTR_ERR(data->clk_cdev1) !=3D -ENOENT) >>>>>>> + return PTR_ERR(data->clk_cdev1); >>>>>>> + /* Fall back to extern1 */ >>>>>>> + data->clk_cdev1 =3D devm_clk_get(dev, "extern1"); >>>>>>> + if (IS_ERR(data->clk_cdev1)) { >>>>>>> + dev_err(data->dev, "Can't retrieve clk extern1\n"); >>>>>>> + return PTR_ERR(data->clk_cdev1); >>>>>>> + } >>>>>>> + >>>>>>> + dev_err(data->dev, "Falling back to extern1\n"); >>>>>> This can be a info print? >>> Will use dev_info >>>>>>> } >>>>>>> /* >>> Dmitry/Rob, there was discussion in v3 regarding backporting mclk >>> fallback. >>> >>> Dmitry wanted Rob to confirm on this >>> >>> I think openSUSE Leap could be one of those distros that use LTS kernel >>> with newer device-trees, but that's not 100%. Maybe Rob could help >>> clarifying that. >>> >>> Dmitry/Rob, Can you please confirm if mclk fallback patch need >>> backport to have new device tree work with old kernels? >>> >> Dmitry, >> >> Can you please confirm if we need to backport this mclk fallback patch? >> > Seems only T210 was making use of the CaR's TEGRA*_CLK_CLK_OUT_*, thus > the backporting isn't needed. Thanks Dmitry > > Also, please use 'git rebase --exec make ...' to make sure that all > patches are compiling without problems. The removal of the legacy clock > IDs should be done after the device-trees changes, otherwise it looks > like DTBs compilation will fail. It's possible that the order of the > patches could be changed if Thierry will chose to split this series into > several pull requests, nevertheless all patches should compile and work > in the original order. OK, Will move patches of device tree updates to use new DT ID prior to=20 removal of old ID.