Date:   Thu, 23 Dec 2021 17:50:02 +0200
From:   Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To:     Jan Dabros <jsd@semihalf.com>
Cc:     linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org,
        jarkko.nikula@linux.intel.com, mika.westerberg@linux.intel.com,
        wsa@kernel.org, rrangel@chromium.org, mw@semihalf.com,
        jaz@semihalf.com, upstream@semihalf.com
Subject: Re: [RFC 1/2] i2c: designware: Add missing locks
Message-ID: <YcSaqmlI7l4H1lsN@smile.fi.intel.com>
References: <20211222094558.2098791-1-jsd@semihalf.com>
 <20211222094558.2098791-2-jsd@semihalf.com>
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In-Reply-To: <20211222094558.2098791-2-jsd@semihalf.com>
Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo
Precedence: bulk

On Wed, Dec 22, 2021 at 10:45:57AM +0100, Jan Dabros wrote:
> All accesses to controller's registers should be protected on
> probe, disable and xfer paths. This is needed for i2c bus controllers
> that are shared with but not controlled by kernel.

...

> +	ret = i2c_dw_acquire_lock(dev);
> +	if (ret)
> +		return ret;
> +
>  	ret = regmap_read(dev->map, DW_IC_COMP_PARAM_1, &param);
>  	if (ret)
>  		return ret;
> +	i2c_dw_release_lock(dev);

Not sure this part is fully correct. Please, fix the leakage.

...

> +	ret = i2c_dw_acquire_lock(dev);
> +	if (ret)
> +		return;
>  
>  	/* Disable controller */
>  	__i2c_dw_disable(dev);
> @@ -614,6 +624,8 @@ void i2c_dw_disable(struct dw_i2c_dev *dev)
>  	/* Disable all interrupts */
>  	regmap_write(dev->map, DW_IC_INTR_MASK, 0);
>  	regmap_read(dev->map, DW_IC_CLR_INTR, &dummy);

> +	i2c_dw_release_lock(dev);

Not enough context here, bu I believe there is the same issue(s).

-- 
With Best Regards,
Andy Shevchenko