On Thu, Jul 12, 2018 at 10:37:38AM +0530, Keerthy wrote: > Prepare rtc driver for rtc-only with DDR in self-refresh mode. > omap_rtc_power_off now should cater to two features: > > 1) RTC plus DDR in self-refresh is power a saving mode where in the > entire system including the different voltage rails from PMIC are > shutdown except the ones feeding on to RTC and DDR. DDR is kept in > self-refresh hence the contents are preserved. RTC ALARM2 is connected > to PMIC_EN line once we the ALARM2 is triggered we enter the mode with > DDR in self-refresh and RTC Ticking. After a predetermined time an RTC > ALARM1 triggers waking up the system[1]. The control goes to bootloader. > The bootloader then checks RTC scratchpad registers to confirm it was an > rtc_only wakeup and follows a different path, configure bare minimal > clocks for ddr and then jumps to the resume address in another RTC > scratchpad registers and transfers the control to Kernel. Kernel then > restores the saved context. omap_rtc_power_off_program does the ALARM2 > programming part. > > [1] http://www.ti.com/lit/ug/spruhl7h/spruhl7h.pdf Page 2884 > > 2) Power-off: This is usual poweroff mode. omap_rtc_power_off calls the > above omap_rtc_power_off_program function and in addition to that > programs the OMAP_RTC_PMIC_REG for any external wake ups for PMIC like > the pushbutton and shuts off the PMIC. > > Hence the split in omap_rtc_power_off. > > Signed-off-by: Keerthy <j-keerthy@xxxxxx> > --- > drivers/rtc/rtc-omap.c | 53 ++++++++++++++++++++++++++++++++++++-------------- > 1 file changed, 38 insertions(+), 15 deletions(-) > > diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c > index 88da927..cb19ece 100644 > --- a/drivers/rtc/rtc-omap.c > +++ b/drivers/rtc/rtc-omap.c > @@ -415,21 +415,12 @@ static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) > > static struct omap_rtc *omap_rtc_power_off_rtc; > > -/* > - * omap_rtc_poweroff: RTC-controlled power off > - * > - * The RTC can be used to control an external PMIC via the pmic_power_en pin, > - * which can be configured to transition to OFF on ALARM2 events. > - * > - * Notes: > - * The two-second alarm offset is the shortest offset possible as the alarm > - * registers must be set before the next timer update and the offset > - * calculation is too heavy for everything to be done within a single access > - * period (~15 us). > - * > - * Called with local interrupts disabled. > +/** > + * omap_rtc_power_off_program: Set the pmic power off sequence. The RTC > + * generates pmic_pwr_enable control, which can be used to control an external > + * PMIC. Since this is kerneldoc, you need an empty line after "sequence." above. You should also add a comment that this function depends on local interrupts being disabled when called (for the wait_not_busy handling); and make sure you follow that in subsequent patches. > */ > -static void omap_rtc_power_off(void) > +static int omap_rtc_power_off_program(struct device *dev) dev is never used in this function. > { > struct omap_rtc *rtc = omap_rtc_power_off_rtc; > struct rtc_time tm; > @@ -456,7 +447,7 @@ static void omap_rtc_power_off(void) > if (tm2bcd(&tm) < 0) { > dev_err(&rtc->rtc->dev, "power off failed\n"); > rtc->type->lock(rtc); > - return; > + return -EINVAL; > } > > rtc_wait_not_busy(rtc); > @@ -481,6 +472,38 @@ static void omap_rtc_power_off(void) > goto again; > rtc->type->lock(rtc); > > + return 0; > +} > + > +/* > + * omap_rtc_poweroff: RTC-controlled power off > + * > + * The RTC can be used to control an external PMIC via the pmic_power_en pin, > + * which can be configured to transition to OFF on ALARM2 events. > + * > + * Notes: > + * The one-second alarm offset is the shortest offset possible as the alarm > + * registers must be set before the next timer update and the offset > + * calculation is too heavy for everything to be done within a single access > + * period (~15 us). This note really doesn't make much sense anymore, and should have been updated as part of the previous patch. > + * > + * Called with local interrupts disabled. > + */ > +static void omap_rtc_power_off(void) > +{ > + struct rtc_device *rtc = omap_rtc_power_off_rtc->rtc; Use struct omap_rtc here as before. > + u32 val; > + > + omap_rtc_power_off_program(rtc->dev.parent); > + > + /* Set PMIC power enable and EXT_WAKEUP in case PB power on is used */ > + omap_rtc_power_off_rtc->type->unlock(omap_rtc_power_off_rtc); > + val = rtc_readl(omap_rtc_power_off_rtc, OMAP_RTC_PMIC_REG); > + val |= OMAP_RTC_PMIC_POWER_EN_EN | OMAP_RTC_PMIC_EXT_WKUP_POL(0) | > + OMAP_RTC_PMIC_EXT_WKUP_EN(0); > + rtc_writel(omap_rtc_power_off_rtc, OMAP_RTC_PMIC_REG, val); > + omap_rtc_power_off_rtc->type->lock(omap_rtc_power_off_rtc); What is all this, and why is it here? Surely fiddling with this register after you've set the alarm to trigger isn't the right thing to do. > + > /* > * Wait for alarm to trigger (within two seconds) and external PMIC to > * power off the system. Add a 500 ms margin for external latencies Johan -- 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
