From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Subject: Re: [PATCH 04/11] input: rohm_bu21023: switch to i2c_lock_segment
Date: Tue, 19 Jun 2018 11:40:00 -0700
Message-ID: <20180619184000.GJ71788@dtor-ws>
References: <20180615101506.8012-1-peda@axentia.se>
 <20180615101506.8012-5-peda@axentia.se>
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To: Peter Rosin <peda@axentia.se>
Cc: linux-kernel@vger.kernel.org, Peter Huewe <peterhuewe@gmx.de>, Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>, Jason Gunthorpe <jgg@ziepe.ca>, Arnd Bergmann <arnd@arndb.de>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Brian Norris <computersforpeace@gmail.com>, Gregory Fong <gregory.0xf0@gmail.com>, Florian Fainelli <f.fainelli@gmail.com>, bcm-kernel-feedback-list@broadcom.com, Sekhar Nori <nsekhar@ti.com>, Kevin Hilman <khilman@kernel.org>, Haavard Skinnemoen <hskinnemoen@gmail.com>, Kukjin Kim <kgene@kernel.org>, Krzysztof Kozlowski <krzk@kernel.org>, Orson Zhai <orsonzhai@gmail.com>, Baolin Wang <baolin.wang@linaro.org>, Chunyan Zhang <zhang.lyra@gmail.com>, Laxman Dewangan <ldewangan@nvidia.com>, Thierry Reding <thierry.reding@gmail.com>
List-Id: linux-i2c@vger.kernel.org

On Fri, Jun 15, 2018 at 12:14:59PM +0200, Peter Rosin wrote:
> Locking the root adapter for __i2c_transfer will deadlock if the
> device sits behind a mux-locked I2C mux. Switch to the finer-grained
> i2c_lock_segment. If the device does not sit behind a mux-locked mux,
> the two locking variants are equivalent.
> 
> Signed-off-by: Peter Rosin <peda@axentia.se>

Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

I'm OK with it going through Wolfram's tree; I do not think I'd need an
immutable branch for this even...

> ---
>  drivers/input/touchscreen/rohm_bu21023.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/input/touchscreen/rohm_bu21023.c b/drivers/input/touchscreen/rohm_bu21023.c
> index bda0500c9b57..22d79db07234 100644
> --- a/drivers/input/touchscreen/rohm_bu21023.c
> +++ b/drivers/input/touchscreen/rohm_bu21023.c
> @@ -304,7 +304,7 @@ static int rohm_i2c_burst_read(struct i2c_client *client, u8 start, void *buf,
>  	msg[1].len = len;
>  	msg[1].buf = buf;
>  
> -	i2c_lock_adapter(adap);
> +	i2c_lock_segment(adap);
>  
>  	for (i = 0; i < 2; i++) {
>  		if (__i2c_transfer(adap, &msg[i], 1) < 0) {
> @@ -313,7 +313,7 @@ static int rohm_i2c_burst_read(struct i2c_client *client, u8 start, void *buf,
>  		}
>  	}
>  
> -	i2c_unlock_adapter(adap);
> +	i2c_unlock_segment(adap);
>  
>  	return ret;
>  }
> -- 
> 2.11.0
> 

Thanks.

-- 
Dmitry