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Date:   Fri, 1 Dec 2023 09:41:16 +0100
From:   Herve Codina <herve.codina@bootlin.com>
To:     "Arnd Bergmann" <arnd@arndb.de>
Cc:     "Qiang Zhao" <qiang.zhao@nxp.com>, "Leo Li" <leoyang.li@nxp.com>,
        "Jakub Kicinski" <kuba@kernel.org>,
        "Shengjiu Wang" <shengjiu.wang@gmail.com>,
        "Xiubo Li" <Xiubo.Lee@gmail.com>,
        "Fabio Estevam" <festevam@gmail.com>,
        "Nicolin Chen" <nicoleotsuka@gmail.com>,
        "Liam Girdwood" <lgirdwood@gmail.com>,
        "Mark Brown" <broonie@kernel.org>,
        "Jaroslav Kysela" <perex@perex.cz>,
        "Takashi Iwai" <tiwai@suse.com>,
        "Christophe Leroy" <christophe.leroy@csgroup.eu>,
        linuxppc-dev@lists.ozlabs.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        alsa-devel@alsa-project.org,
        "Thomas Petazzoni" <thomas.petazzoni@bootlin.com>
Subject: Re: [PATCH 15/17] soc: fsl: cpm1: qmc: Handle timeslot entries at
 channel start() and stop()
Message-ID: <20231201094116.65956f60@bootlin.com>
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        <46d0248d-c322-4856-8e9e-6468ac1b7a02@app.fastmail.com>
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Hi Arnd,

On Wed, 29 Nov 2023 15:03:02 +0100
"Arnd Bergmann" <arnd@arndb.de> wrote:

> On Tue, Nov 28, 2023, at 15:08, Herve Codina wrote:
> > @@ -272,6 +274,8 @@ int qmc_chan_get_info(struct qmc_chan *chan, struct 
> > qmc_chan_info *info)
> >  	if (ret)
> >  		return ret;
> > 
> > +	spin_lock_irqsave(&chan->ts_lock, flags);
> > +
> >  	info->mode = chan->mode;
> >  	info->rx_fs_rate = tsa_info.rx_fs_rate;
> >  	info->rx_bit_rate = tsa_info.rx_bit_rate;
> > @@ -280,6 +284,8 @@ int qmc_chan_get_info(struct qmc_chan *chan, struct 
> > qmc_chan_info *info)
> >  	info->tx_bit_rate = tsa_info.tx_bit_rate;
> >  	info->nb_rx_ts = hweight64(chan->rx_ts_mask);
> > 
> > +	spin_unlock_irqrestore(&chan->ts_lock, flags);
> > +
> >  	return 0;
> >  }  
> 
> I would normally use spin_lock_irq() instead of spin_lock_irqsave()
> in functions that are only called outside of atomic context.

I would prefer to keep spin_lock_irqsave() here.
This function is part of the API and so, its quite difficult to ensure
that all calls (current and future) will be done outside of an atomic
context.

> 
> > +static int qmc_chan_start_rx(struct qmc_chan *chan);
> > +
> >  int qmc_chan_stop(struct qmc_chan *chan, int direction)
> >  {  
> ... 
> > -static void qmc_chan_start_rx(struct qmc_chan *chan)
> > +static int qmc_setup_chan_trnsync(struct qmc *qmc, struct qmc_chan *chan);
> > +
> > +static int qmc_chan_start_rx(struct qmc_chan *chan)
> >  {  
> 
> Can you reorder the static functions in a way that avoids the
> forward declarations?

Yes, sure.
I will do that in the next iteration.

Thanks for the review,

Best regards,
Hervé