Message-ID: <1476293049.11323.453.camel@linux.intel.com>
Subject: Re: [PATCH] mfd: intel-lpss: Do not put device in reset state on
 suspend
From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: Azhar Shaikh <azhar.shaikh@intel.com>, lee.jones@linaro.org
Cc: heikki.krogerus@linux.intel.com, mika.westerberg@linux.intel.com,
        linux-kernel@vger.kernel.org
Date: Wed, 12 Oct 2016 20:24:09 +0300
In-Reply-To: <20161012171220.6429-1-azhar.shaikh@intel.com>
References: <20161012171220.6429-1-azhar.shaikh@intel.com>
Organization: Intel Finland Oy
Content-Type: text/plain; charset="UTF-8"
Mime-Version: 1.0
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1322
Lines: 38

On Wed, 2016-10-12 at 10:12 -0700, Azhar Shaikh wrote:
> Commit 41a3da2b8e163 ("mfd: intel-lpss: Save register context on
> suspend") saved the register context while going to suspend and
> also put the device in reset state.
> 
> Due to the resetting of device, system cannot enter S3/S0ix
> states when no_console_suspend flag is enabled. The system
> and serial console both hang. The resetting of device is not
> needed while going to suspend. Hence remove this code.
> 
> Fixes: 41a3da2b8e163 ("mfd: intel-lpss: Save register context on
> suspend")
> Signed-off-by: Azhar Shaikh <azhar.shaikh@intel.com>

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

> ---
>  drivers/mfd/intel-lpss.c | 3 ---
>  1 file changed, 3 deletions(-)
> 
> diff --git a/drivers/mfd/intel-lpss.c b/drivers/mfd/intel-lpss.c
> index 41b1138..70c646b 100644
> --- a/drivers/mfd/intel-lpss.c
> +++ b/drivers/mfd/intel-lpss.c
> @@ -502,9 +502,6 @@ int intel_lpss_suspend(struct device *dev)
>  	for (i = 0; i < LPSS_PRIV_REG_COUNT; i++)
>  		lpss->priv_ctx[i] = readl(lpss->priv + i * 4);
>  
> -	/* Put the device into reset state */
> -	writel(0, lpss->priv + LPSS_PRIV_RESETS);
> -
>  	return 0;
>  }
>  EXPORT_SYMBOL_GPL(intel_lpss_suspend);

-- 
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy