| Message ID | 20200723074314.3304-4-horia.geanta@nxp.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | input: i.MX snvs powerkey updates | expand |
Hi, On 20-07-23 10:43, Horia Geantă wrote: > From: André Draszik <git@andred.net> > > The snvs_pwrkey shares the SNVS LPSR status register with the snvs_rtc. > > This driver here should only return IRQ_HANDLED if the status register > indicates that the event we're handling in the irq handler was genuinely > intended for this driver. Otheriwse the interrupt subsystem will > assume the interrupt was handled successfully even though it wasn't > at all. After checking the RM and the imx6qdl.dtsi I'm not very sure that this is right since the snvs-powerkey has a seperate irq-line. So we can be sure that this irq is for us. If this is the case we don't need to check the SNVS_LPSR_REG instead we only need to clear it. Regards, Marco
Hi Marco, On Wed, Jul 29, 2020 at 09:55:13AM +0200, Marco Felsch wrote: > Hi, > > On 20-07-23 10:43, Horia Geantă wrote: > > From: André Draszik <git@andred.net> > > > > The snvs_pwrkey shares the SNVS LPSR status register with the snvs_rtc. > > > > This driver here should only return IRQ_HANDLED if the status register > > indicates that the event we're handling in the irq handler was genuinely > > intended for this driver. Otheriwse the interrupt subsystem will > > assume the interrupt was handled successfully even though it wasn't > > at all. > > After checking the RM and the imx6qdl.dtsi I'm not very sure that this > is right since the snvs-powerkey has a seperate irq-line. So we can be > sure that this irq is for us. If this is the case we don't need to check > the SNVS_LPSR_REG instead we only need to clear it. Wouldn't we want to know if for some reason we get spurious interrupts? Thanks.
Hi Dmitry, On 20-07-29 23:06, Dmitry Torokhov wrote: > Hi Marco, > > On Wed, Jul 29, 2020 at 09:55:13AM +0200, Marco Felsch wrote: > > Hi, > > > > On 20-07-23 10:43, Horia Geantă wrote: > > > From: André Draszik <git@andred.net> > > > > > > The snvs_pwrkey shares the SNVS LPSR status register with the snvs_rtc. > > > > > > This driver here should only return IRQ_HANDLED if the status register > > > indicates that the event we're handling in the irq handler was genuinely > > > intended for this driver. Otheriwse the interrupt subsystem will > > > assume the interrupt was handled successfully even though it wasn't > > > at all. > > > > After checking the RM and the imx6qdl.dtsi I'm not very sure that this > > is right since the snvs-powerkey has a seperate irq-line. So we can be > > sure that this irq is for us. If this is the case we don't need to check > > the SNVS_LPSR_REG instead we only need to clear it. > > Wouldn't we want to know if for some reason we get spurious interrupts? We could check the bit at the very begin of the IRQ and return early but according the RM this should never happen. Anyway you're right HW is never bug free. Regards, Marco > Thanks. > > -- > Dmitry
diff --git a/drivers/input/keyboard/snvs_pwrkey.c b/drivers/input/keyboard/snvs_pwrkey.c index 382d2ae82c9b..980867886b34 100644 --- a/drivers/input/keyboard/snvs_pwrkey.c +++ b/drivers/input/keyboard/snvs_pwrkey.c @@ -82,7 +82,9 @@ static irqreturn_t imx_snvs_pwrkey_interrupt(int irq, void *dev_id) clk_enable(pdata->clk); regmap_read(pdata->snvs, SNVS_LPSR_REG, &lp_status); - if (lp_status & SNVS_LPSR_SPO) { + lp_status &= SNVS_LPSR_SPO; + + if (lp_status) { if (pdata->minor_rev == 0) { /* * The first generation i.MX[6|7] SoCs only send an @@ -98,14 +100,14 @@ static irqreturn_t imx_snvs_pwrkey_interrupt(int irq, void *dev_id) mod_timer(&pdata->check_timer, jiffies + msecs_to_jiffies(DEBOUNCE_TIME)); } - } - /* clear SPO status */ - regmap_write(pdata->snvs, SNVS_LPSR_REG, SNVS_LPSR_SPO); + /* clear SPO status */ + regmap_write(pdata->snvs, SNVS_LPSR_REG, SNVS_LPSR_SPO); + } clk_disable(pdata->clk); - return IRQ_HANDLED; + return lp_status ? IRQ_HANDLED : IRQ_NONE; } static void imx_snvs_pwrkey_act(void *pdata)