Re: [PATCH v7 3/5] RTC: RK808: add RTC driver for RK808

From: Chris Zhong
Date: Tue Sep 02 2014 - 22:01:59 EST

On 09/02/2014 11:58 AM, Doug Anderson wrote:
+static int rk808_rtc_probe(struct platform_device *pdev)
>+ struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent);
>+ struct rk808_rtc *rk808_rtc;
>+ struct rtc_time tm;
>+ int ret;
>+ rk808_rtc = devm_kzalloc(&pdev->dev, sizeof(*rk808_rtc), GFP_KERNEL);
>+ if (rk808_rtc == NULL)
>+ return -ENOMEM;
>+ platform_set_drvdata(pdev, rk808_rtc);
>+ rk808_rtc->rk808 = rk808;
>+ /* start rtc running by default, and use shadowed timer. */
>+ ret = regmap_update_bits(rk808->regmap, RK808_RTC_CTRL_REG,
I think this should still be setting to 0, not to
BIT_RTC_CTRL_REG_RTC_READSEL_M. Otherwise the first read of the time
will return that time that was frozen at probe time, right? AKA: if
probe happens at 11:00:00 and then we read the time at 11:00:05 we'll
still read 11:00:00 the first time.

Sorry, I did not describe correctly, in the previous mail.
Actually, RK808 has a "GET_TIME" switch bit. When "GET_TIME" bit rising thansiton to 1,
the current time will save in a shadowed register.
If "READSEL" = 1, read rtc time register, return the frozen time.
If we need the real time, clr this "READSEL" bit.

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