Hi,
Not much to add, apart from the spinlock issue already spotted by Andrew.
On 27/08/2017 at 02:33:27 +0200, Andreas Färber wrote:
> +struct rtd119x_rtc {
> + void __iomem *base;
> + struct clk *clk;
> + struct rtc_device *rtcdev;
> + unsigned base_year;
checkpatch complains this should be made unsigned int
> + spinlock_t lock;
> +};
> +
> +static inline int rtd119x_rtc_year_days(int year)
> +{
> + return rtc_year_days(1, 12, year);
I'm not sure it is worth wrapping rtc_year_days
> +static int rtd119x_rtc_read_time(struct device *dev, struct rtc_time *tm)
> +{
> + struct rtd119x_rtc *data = dev_get_drvdata(dev);
> + unsigned long flags;
> + s32 day;
> + u32 sec;
> + unsigned year;
unsigned int
> + int tries = 0;
> +
> + spin_lock_irqsave(&data->lock, flags);
> +
> + while (true) {
> + tm->tm_sec = (readl_relaxed(data->base + RTD_RTCSEC) & RTD_RTCSEC_RTCSEC_MASK) >> 1;
> + tm->tm_min = readl_relaxed(data->base + RTD_RTCMIN) & RTD_RTCMIN_RTCMIN_MASK;
> + tm->tm_hour = readl_relaxed(data->base + RTD_RTCHR) & RTD_RTCHR_RTCHR_MASK;
> + day = readl_relaxed(data->base + RTD_RTCDATE1) & RTD_RTCDATE1_RTCDATE1_MASK;
> + day |= (readl_relaxed(data->base + RTD_RTCDATE2) & RTD_RTCDATE2_RTCDATE2_MASK) << 8;
> + sec = (readl_relaxed(data->base + RTD_RTCSEC) & RTD_RTCSEC_RTCSEC_MASK) >> 1;
> + tries++;
> +
> + if (sec == tm->tm_sec)
> + break;
> +
> + if (tries >= 3) {
> + spin_unlock_irqrestore(&data->lock, flags);
> + return -EINVAL;
> + }
> + }
> + if (tries > 1)
> + dev_dbg(dev, "%s: needed %i tries\n", __func__, tries);
> +
> + spin_unlock_irqrestore(&data->lock, flags);
> +
> + year = data->base_year;
> + while (day >= rtd119x_rtc_year_days(year)) {
> + day -= rtd119x_rtc_year_days(year);
> + year++;
> + }
> + tm->tm_year = year - 1900;
> + tm->tm_yday = day;
> +
> + tm->tm_mon = 0;
> + while (day >= rtc_month_days(tm->tm_mon, year)) {
> + day -= rtc_month_days(tm->tm_mon, year);
> + tm->tm_mon++;
> + }
> + tm->tm_mday = day + 1;
> +
> + return rtc_valid_tm(tm);
As you spotted, you can return 0 here.
> +}
> +
> +static int rtd119x_rtc_set_time(struct device *dev, struct rtc_time *tm)
> +{
> + struct rtd119x_rtc *data = dev_get_drvdata(dev);
> + unsigned long flags;
> + unsigned day;
ditto
--
Alexandre Belloni, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
