From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1752216Ab3KRNWo (ORCPT <rfc822;w@1wt.eu>);
	Mon, 18 Nov 2013 08:22:44 -0500
Received: from devils.ext.ti.com ([198.47.26.153]:53914 "EHLO
	devils.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1751185Ab3KRNWh (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Mon, 18 Nov 2013 08:22:37 -0500
Message-ID: <528A1444.8020802@ti.com>
Date: Mon, 18 Nov 2013 15:21:08 +0200
From: "ivan.khoronzhuk" <ivan.khoronzhuk@ti.com>
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.1.0
MIME-Version: 1.0
To: Guenter Roeck <linux@roeck-us.net>,
        Santosh Shilimkar <santosh.shilimkar@ti.com>, <wim@iguana.be>,
        <nsekhar@ti.com>, <linux-watchdog@vger.kernel.org>,
        <devicetree@vger.kernel.org>
CC: <grant.likely@linaro.org>, <rob.herring@calxeda.com>, <pawel.moll@arm.com>,
        <mark.rutland@arm.com>, <swarren@wwwdotorg.org>,
        <galak@kernel.crashing.org>, <ijc+devicetree@hellion.org.uk>,
        <linux-kernel@vger.kernel.org>, <linux-arm-kernel@lists.infradead.org>
Subject: Re: Fwd: [PATCH 3/8] watchdog: davinci: add GET_TIMELEFT option support
References: <1383680783-12114-4-git-send-email-ivan.khoronzhuk@ti.com> <527A28AF.9040308@ti.com> <5288284A.4020803@roeck-us.net>
In-Reply-To: <5288284A.4020803@roeck-us.net>
Content-Type: text/plain; charset="ISO-8859-1"; format=flowed
Content-Transfer-Encoding: 7bit
X-Originating-IP: [10.167.145.122]
X-EXCLAIMER-MD-CONFIG: f9c360f5-3d1e-4c3c-8703-f45bf52eff6b
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On 11/17/2013 04:22 AM, Guenter Roeck wrote:
> On 11/06/2013 03:31 AM, ivan.khoronzhuk wrote:
>> Currently, the davinci watchdog can be read while counting,
>> so we can add ability to report the remaining time before
>> the system will reboot.
>>
>> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@ti.com>
>> ---
>>   drivers/watchdog/davinci_wdt.c |   28 ++++++++++++++++++++++++++++
>>   1 file changed, 28 insertions(+)
>>
>> diff --git a/drivers/watchdog/davinci_wdt.c
>> b/drivers/watchdog/davinci_wdt.c
>> index 1fc2093..6cbf2e1 100644
>> --- a/drivers/watchdog/davinci_wdt.c
>> +++ b/drivers/watchdog/davinci_wdt.c
>> @@ -117,6 +117,33 @@ static int davinci_wdt_ping(struct
>> watchdog_device *wdd)
>>       return 0;
>>   }
>>
>> +static unsigned int davinci_wdt_get_timeleft(struct watchdog_device
>> *wdd)
>> +{
>> +    u64 timer_counter;
>> +    unsigned long freq;
>> +    u32 val;
>> +    struct davinci_wdt_device *davinci_wdt = watchdog_get_drvdata(wdd);
>> +
>> +    /* if timeout is occured then return 0 */
>
> is -> has ?
>

Yes

>> +    val = ioread32(davinci_wdt->base + WDTCR);
>> +    if (val & WDFLAG)
>> +        return 0;
>> +
>> +    freq = clk_get_rate(davinci_wdt->clk);
>> +
>> +    if (!freq) {
>> +        dev_err(wdd->dev, "clock freq is not set\n");
>> +        return 0;
>> +    }
>> +
> This error check doesn't make sense to me; elsewhere the clock rate is
> not validated.
> I would suggest to just return 0 here.
>

Agree

>> +    timer_counter = ioread32(davinci_wdt->base + TIM12);
>> +    timer_counter |= ((u64)ioread32(davinci_wdt->base + TIM34) << 32);
>> +
>> +    do_div(timer_counter, freq);
>> +
>> +    return wdd->timeout - timer_counter;
>> +}
>> +
>>   static const struct watchdog_info davinci_wdt_info = {
>>       .options = WDIOF_KEEPALIVEPING,
>>       .identity = "DaVinci Watchdog",
>> @@ -127,6 +154,7 @@ static const struct watchdog_ops davinci_wdt_ops = {
>>       .start        = davinci_wdt_start,
>>       .stop        = davinci_wdt_ping,
>>       .ping        = davinci_wdt_ping,
>> +    .get_timeleft    = davinci_wdt_get_timeleft,
>>   };
>>
>>   static int davinci_wdt_probe(struct platform_device *pdev)
>>
>


-- 
Regards,
Ivan Khoronzhuk