On Friday 05 May 2017 04:08 AM, Alexandre Belloni wrote: > Hi, > > On 03/05/2017 at 11:39:34 +0530, Keerthy wrote: >> On Tuesday 18 April 2017 10:50 AM, Keerthy wrote: >>> From: Russ Dill <Russ.Dill@xxxxxx> >>> >>> Many RTCs provide scratch registers that are maintained so long as the RTC >>> has power. Provide a generic method to access these registers. >>> >> >> A gentle ping on this >> > > Yeah, I apologize for the delay (I know you already sent this 6-8 months > ago). > I'm not satisfied with the interface (and its name). I gave a lot of > thought into it and I'm currently reworking part of the subsystem to > create a similar feature. I'm planning to have it in 4.13. Okay then i will wait for that. Thanks for the response. > >>> Signed-off-by: Russ Dill <Russ.Dill@xxxxxx> >>> Signed-off-by: Keerthy <j-keerthy@xxxxxx> >>> --- >>> drivers/rtc/interface.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++++ >>> drivers/rtc/rtc-omap.c | 35 ++++++++++++++++++++++++++++++++++ >>> include/linux/rtc.h | 7 +++++++ >>> 3 files changed, 92 insertions(+) >>> >>> diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c >>> index fc0fa75..facde06 100644 >>> --- a/drivers/rtc/interface.c >>> +++ b/drivers/rtc/interface.c >>> @@ -1016,3 +1016,53 @@ int rtc_set_offset(struct rtc_device *rtc, long offset) >>> mutex_unlock(&rtc->ops_lock); >>> return ret; >>> } >>> + >>> +/* rtc_read_scratch - Read from RTC scratch register >>> + * @ rtc: rtc device to be used >>> + * @ index: index of scratch register >>> + * @ value: returned value read >>> + * >>> + * Kernel interface read from an RTC scratch register >>> + */ >>> +int rtc_read_scratch(struct rtc_device *rtc, unsigned int index, u32 *value) >>> +{ >>> + int err; >>> + >>> + mutex_lock(&rtc->ops_lock); >>> + if (!rtc->ops) >>> + err = -ENODEV; >>> + else if (index >= rtc->ops->scratch_size || !rtc->ops->read_scratch) >>> + err = -EINVAL; >>> + else >>> + err = rtc->ops->read_scratch(rtc->dev.parent, index, value); >>> + mutex_unlock(&rtc->ops_lock); >>> + return err; >>> +} >>> +EXPORT_SYMBOL_GPL(rtc_read_scratch); >>> + >>> +/* rtc_write_scratch - Write to RTC scratch register >>> + * @ rtc: rtc device to be used >>> + * @ index: index of scratch register >>> + * @ value: value to write >>> + * >>> + * Kernel interface write to an RTC scratch register >>> + */ >>> +int rtc_write_scratch(struct rtc_device *rtc, unsigned int index, u32 value) >>> +{ >>> + int err; >>> + >>> + mutex_lock(&rtc->ops_lock); >>> + >>> + if (!rtc->ops) >>> + err = -ENODEV; >>> + else if (index >= rtc->ops->scratch_size || >>> + !rtc->ops->write_scratch) >>> + err = -EINVAL; >>> + else >>> + err = rtc->ops->write_scratch(rtc->dev.parent, index, value); >>> + >>> + mutex_unlock(&rtc->ops_lock); >>> + >>> + return err; >>> +} >>> +EXPORT_SYMBOL_GPL(rtc_write_scratch); >>> diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c >>> index 13f7cd1..c90d93e 100644 >>> --- a/drivers/rtc/rtc-omap.c >>> +++ b/drivers/rtc/rtc-omap.c >>> @@ -70,6 +70,10 @@ >>> #define OMAP_RTC_COMP_MSB_REG 0x50 >>> #define OMAP_RTC_OSC_REG 0x54 >>> >>> +#define OMAP_RTC_SCRATCH0_REG 0x60 >>> +#define OMAP_RTC_SCRATCH1_REG 0x64 >>> +#define OMAP_RTC_SCRATCH2_REG 0x68 >>> + >>> #define OMAP_RTC_KICK0_REG 0x6c >>> #define OMAP_RTC_KICK1_REG 0x70 >>> >>> @@ -414,6 +418,34 @@ static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) >>> >>> static struct omap_rtc *omap_rtc_power_off_rtc; >>> >>> +static const u32 omap_rtc_scratch_regs[] = { >>> + OMAP_RTC_SCRATCH0_REG, >>> + OMAP_RTC_SCRATCH1_REG, >>> + OMAP_RTC_SCRATCH2_REG, >>> +}; >>> + >>> +static int omap_rtc_read_scratch(struct device *dev, unsigned int index, >>> + u32 *value) >>> +{ >>> + *value = readl(omap_rtc_power_off_rtc->base + >>> + omap_rtc_scratch_regs[index]); >>> + >>> + return 0; >>> +} >>> + >>> +static int omap_rtc_write_scratch(struct device *dev, unsigned int index, >>> + u32 value) >>> +{ >>> + struct omap_rtc *rtc = dev_get_drvdata(dev); >>> + >>> + rtc->type->unlock(rtc); >>> + writel(value, omap_rtc_power_off_rtc->base + >>> + omap_rtc_scratch_regs[index]); >>> + rtc->type->lock(rtc); >>> + >>> + return 0; >>> +} >>> + >>> /* >>> * omap_rtc_poweroff: RTC-controlled power off >>> * >>> @@ -484,6 +516,9 @@ static void omap_rtc_power_off(void) >>> .read_alarm = omap_rtc_read_alarm, >>> .set_alarm = omap_rtc_set_alarm, >>> .alarm_irq_enable = omap_rtc_alarm_irq_enable, >>> + .read_scratch = omap_rtc_read_scratch, >>> + .write_scratch = omap_rtc_write_scratch, >>> + .scratch_size = ARRAY_SIZE(omap_rtc_scratch_regs), >>> }; >>> >>> static const struct omap_rtc_device_type omap_rtc_default_type = { >>> diff --git a/include/linux/rtc.h b/include/linux/rtc.h >>> index b693ada..da5e003 100644 >>> --- a/include/linux/rtc.h >>> +++ b/include/linux/rtc.h >>> @@ -91,6 +91,10 @@ struct rtc_class_ops { >>> int (*alarm_irq_enable)(struct device *, unsigned int enabled); >>> int (*read_offset)(struct device *, long *offset); >>> int (*set_offset)(struct device *, long offset); >>> + int (*read_scratch)(struct device *, unsigned int, u32*); >>> + int (*write_scratch)(struct device *, unsigned int, u32); >>> + >>> + unsigned int scratch_size; >>> }; >>> >>> #define RTC_DEVICE_NAME_SIZE 20 >>> @@ -214,6 +218,9 @@ int rtc_timer_start(struct rtc_device *rtc, struct rtc_timer *timer, >>> int rtc_set_offset(struct rtc_device *rtc, long offset); >>> void rtc_timer_do_work(struct work_struct *work); >>> >>> +int rtc_read_scratch(struct rtc_device *rtc, unsigned int index, u32 *value); >>> +int rtc_write_scratch(struct rtc_device *rtc, unsigned int index, u32 value); >>> + >>> static inline bool is_leap_year(unsigned int year) >>> { >>> return (!(year % 4) && (year % 100)) || !(year % 400); >>> > -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html