On Thu, Jan 21, 2021 at 3:52 PM Hailong Fan <[email protected]> wrote:
>
> When flipping the polarity will be generated interrupt under certain
> circumstances, but GPIO external signal has not changed.
> Then, mask the interrupt before polarity setting, and clear the
> unexpected interrupt after trigger type setting completed.
>
> Signed-off-by: Hailong Fan <[email protected]>
> ---
> Resend since some server reject.
> ---
> drivers/pinctrl/mediatek/mtk-eint.c | 13 +++++++++++--
> 1 file changed, 11 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/pinctrl/mediatek/mtk-eint.c b/drivers/pinctrl/mediatek/mtk-eint.c
> index 22736f60c16c..3acda6bb401e 100644
> --- a/drivers/pinctrl/mediatek/mtk-eint.c
> +++ b/drivers/pinctrl/mediatek/mtk-eint.c
> @@ -157,6 +157,7 @@ static void mtk_eint_ack(struct irq_data *d)
> static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
> {
> struct mtk_eint *eint = irq_data_get_irq_chip_data(d);
> + unsigned int unmask;
bool?
> u32 mask = BIT(d->hwirq & 0x1f);
> void __iomem *reg;
>
> @@ -173,6 +174,13 @@ static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
> else
> eint->dual_edge[d->hwirq] = 0;
>
> + if (!mtk_eint_get_mask(eint, d->hwirq)) {
> + mtk_eint_mask(d);
> + unmask = 1;
> + } else {
> + unmask = 0;
> + }
> +
> if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_EDGE_FALLING)) {
> reg = mtk_eint_get_offset(eint, d->hwirq, eint->regs->pol_clr);
> writel(mask, reg);
> @@ -189,8 +197,9 @@ static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
> writel(mask, reg);
> }
>
> - if (eint->dual_edge[d->hwirq])
> - mtk_eint_flip_edge(eint, d->hwirq);
Why are you dropping this? Aren't we at risk to miss the first edge
after mtk_eint_set_type is called?
> + mtk_eint_ack(d);
> + if (unmask == 1)
Just `if (unmask)`
> + mtk_eint_unmask(d);
>
> return 0;
> }
> --
> 2.18.0
On Thu, 2021-01-21 at 16:55 +0800, Nicolas Boichat wrote:
> On Thu, Jan 21, 2021 at 3:52 PM Hailong Fan <[email protected]> wrote:
> >
> > When flipping the polarity will be generated interrupt under certain
> > circumstances, but GPIO external signal has not changed.
> > Then, mask the interrupt before polarity setting, and clear the
> > unexpected interrupt after trigger type setting completed.
> >
> > Signed-off-by: Hailong Fan <[email protected]>
> > ---
> > Resend since some server reject.
> > ---
> > drivers/pinctrl/mediatek/mtk-eint.c | 13 +++++++++++--
> > 1 file changed, 11 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/pinctrl/mediatek/mtk-eint.c b/drivers/pinctrl/mediatek/mtk-eint.c
> > index 22736f60c16c..3acda6bb401e 100644
> > --- a/drivers/pinctrl/mediatek/mtk-eint.c
> > +++ b/drivers/pinctrl/mediatek/mtk-eint.c
> > @@ -157,6 +157,7 @@ static void mtk_eint_ack(struct irq_data *d)
> > static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
> > {
> > struct mtk_eint *eint = irq_data_get_irq_chip_data(d);
> > + unsigned int unmask;
>
> bool?
Yes,thanks.
>
> > u32 mask = BIT(d->hwirq & 0x1f);
> > void __iomem *reg;
> >
> > @@ -173,6 +174,13 @@ static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
> > else
> > eint->dual_edge[d->hwirq] = 0;
> >
> > + if (!mtk_eint_get_mask(eint, d->hwirq)) {
> > + mtk_eint_mask(d);
> > + unmask = 1;
> > + } else {
> > + unmask = 0;
> > + }
> > +
> > if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_EDGE_FALLING)) {
> > reg = mtk_eint_get_offset(eint, d->hwirq, eint->regs->pol_clr);
> > writel(mask, reg);
> > @@ -189,8 +197,9 @@ static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
> > writel(mask, reg);
> > }
> >
> > - if (eint->dual_edge[d->hwirq])
> > - mtk_eint_flip_edge(eint, d->hwirq);
>
> Why are you dropping this? Aren't we at risk to miss the first edge
> after mtk_eint_set_type is called?
mtk_eint_unmask() will do it.
If unmask != 1, user need to call mtk_eint_unmask() to enable the
interrupt before use it, thanks.
> > + mtk_eint_ack(d);
> > + if (unmask == 1)
>
> Just `if (unmask)`
Yes,thanks.
> > + mtk_eint_unmask(d);
> >
> > return 0;
> > }
> > --
> > 2.18.0
On Thu, Jan 21, 2021 at 8:09 PM mtk15103 <[email protected]> wrote:
>
> On Thu, 2021-01-21 at 16:55 +0800, Nicolas Boichat wrote:
> > On Thu, Jan 21, 2021 at 3:52 PM Hailong Fan <[email protected]> wrote:
> > >
> > > When flipping the polarity will be generated interrupt under certain
> > > circumstances, but GPIO external signal has not changed.
> > > Then, mask the interrupt before polarity setting, and clear the
> > > unexpected interrupt after trigger type setting completed.
> > >
> > > Signed-off-by: Hailong Fan <[email protected]>
> > > ---
> > > Resend since some server reject.
> > > ---
> > > drivers/pinctrl/mediatek/mtk-eint.c | 13 +++++++++++--
> > > 1 file changed, 11 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/pinctrl/mediatek/mtk-eint.c b/drivers/pinctrl/mediatek/mtk-eint.c
> > > index 22736f60c16c..3acda6bb401e 100644
> > > --- a/drivers/pinctrl/mediatek/mtk-eint.c
> > > +++ b/drivers/pinctrl/mediatek/mtk-eint.c
> > > @@ -157,6 +157,7 @@ static void mtk_eint_ack(struct irq_data *d)
> > > static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
> > > {
> > > struct mtk_eint *eint = irq_data_get_irq_chip_data(d);
> > > + unsigned int unmask;
> >
> > bool?
> Yes,thanks.
> >
> > > u32 mask = BIT(d->hwirq & 0x1f);
> > > void __iomem *reg;
> > >
> > > @@ -173,6 +174,13 @@ static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
> > > else
> > > eint->dual_edge[d->hwirq] = 0;
> > >
> > > + if (!mtk_eint_get_mask(eint, d->hwirq)) {
> > > + mtk_eint_mask(d);
> > > + unmask = 1;
> > > + } else {
> > > + unmask = 0;
> > > + }
> > > +
> > > if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_EDGE_FALLING)) {
> > > reg = mtk_eint_get_offset(eint, d->hwirq, eint->regs->pol_clr);
> > > writel(mask, reg);
> > > @@ -189,8 +197,9 @@ static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
> > > writel(mask, reg);
> > > }
> > >
> > > - if (eint->dual_edge[d->hwirq])
> > > - mtk_eint_flip_edge(eint, d->hwirq);
> >
> > Why are you dropping this? Aren't we at risk to miss the first edge
> > after mtk_eint_set_type is called?
> mtk_eint_unmask() will do it.
> If unmask != 1, user need to call mtk_eint_unmask() to enable the
> interrupt before use it, thanks.
Makes sense, I just have one more worry:
https://elixir.bootlin.com/linux/latest/source/drivers/pinctrl/mediatek/mtk-eint.c#L122
mtk_eint_unmask unmasks the interrupt _before_ the edge is flipped,
could this cause a spurious interrupt? On any unmask operation -- not
just on mtk_eint_set_type (so this is technically another problem,
that should be fixed as a separate patch)
> > > + mtk_eint_ack(d);
> > > + if (unmask == 1)
> >
> > Just `if (unmask)`
> Yes,thanks.
> > > + mtk_eint_unmask(d);
> > >
> > > return 0;
> > > }
> > > --
> > > 2.18.0
>
On Thu, 2021-01-21 at 20:13 +0800, Nicolas Boichat wrote:
> On Thu, Jan 21, 2021 at 8:09 PM mtk15103 <[email protected]> wrote:
> >
> > On Thu, 2021-01-21 at 16:55 +0800, Nicolas Boichat wrote:
> > > On Thu, Jan 21, 2021 at 3:52 PM Hailong Fan <[email protected]> wrote:
> > > >
> > > > When flipping the polarity will be generated interrupt under certain
> > > > circumstances, but GPIO external signal has not changed.
> > > > Then, mask the interrupt before polarity setting, and clear the
> > > > unexpected interrupt after trigger type setting completed.
> > > >
> > > > Signed-off-by: Hailong Fan <[email protected]>
> > > > ---
> > > > Resend since some server reject.
> > > > ---
> > > > drivers/pinctrl/mediatek/mtk-eint.c | 13 +++++++++++--
> > > > 1 file changed, 11 insertions(+), 2 deletions(-)
> > > >
> > > > diff --git a/drivers/pinctrl/mediatek/mtk-eint.c b/drivers/pinctrl/mediatek/mtk-eint.c
> > > > index 22736f60c16c..3acda6bb401e 100644
> > > > --- a/drivers/pinctrl/mediatek/mtk-eint.c
> > > > +++ b/drivers/pinctrl/mediatek/mtk-eint.c
> > > > @@ -157,6 +157,7 @@ static void mtk_eint_ack(struct irq_data *d)
> > > > static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
> > > > {
> > > > struct mtk_eint *eint = irq_data_get_irq_chip_data(d);
> > > > + unsigned int unmask;
> > >
> > > bool?
> > Yes,thanks.
> > >
> > > > u32 mask = BIT(d->hwirq & 0x1f);
> > > > void __iomem *reg;
> > > >
> > > > @@ -173,6 +174,13 @@ static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
> > > > else
> > > > eint->dual_edge[d->hwirq] = 0;
> > > >
> > > > + if (!mtk_eint_get_mask(eint, d->hwirq)) {
> > > > + mtk_eint_mask(d);
> > > > + unmask = 1;
> > > > + } else {
> > > > + unmask = 0;
> > > > + }
> > > > +
> > > > if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_EDGE_FALLING)) {
> > > > reg = mtk_eint_get_offset(eint, d->hwirq, eint->regs->pol_clr);
> > > > writel(mask, reg);
> > > > @@ -189,8 +197,9 @@ static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
> > > > writel(mask, reg);
> > > > }
> > > >
> > > > - if (eint->dual_edge[d->hwirq])
> > > > - mtk_eint_flip_edge(eint, d->hwirq);
> > >
> > > Why are you dropping this? Aren't we at risk to miss the first edge
> > > after mtk_eint_set_type is called?
> > mtk_eint_unmask() will do it.
> > If unmask != 1, user need to call mtk_eint_unmask() to enable the
> > interrupt before use it, thanks.
>
> Makes sense, I just have one more worry:
> https://elixir.bootlin.com/linux/latest/source/drivers/pinctrl/mediatek/mtk-eint.c#L122
>
> mtk_eint_unmask unmasks the interrupt _before_ the edge is flipped,
> could this cause a spurious interrupt? On any unmask operation -- not
> just on mtk_eint_set_type (so this is technically another problem,
> that should be fixed as a separate patch)
This situation will not happen.
Spurious interrupt occur condition: edge irq polarity value is same with
input signal.
e.g.
Default value: GPIO input is high, trigger type is falling_edge.
User want modify trigger type is rising_edge under some certain
circumstances, it will generate spurious interrupt but external signal
maintain high.
So we need ack interrupt after trigger_type setting is completed.
mtk_eint_flip_edge is for dual_edge, the polarity setting based on
current gpio input signal:
if (input == high)
polarity = low; /* falling_edge */
else
polarity = high; /* rising_edge */
Then it's not cause a spurious interrupt.
> > > > + mtk_eint_ack(d);
> > > > + if (unmask == 1)
> > >
> > > Just `if (unmask)`
> > Yes,thanks.
> > > > + mtk_eint_unmask(d);
> > > >
> > > > return 0;
> > > > }
> > > > --
> > > > 2.18.0
> >
On Fri, Jan 22, 2021 at 10:44 AM mtk15103 <[email protected]> wrote:
>
> On Thu, 2021-01-21 at 20:13 +0800, Nicolas Boichat wrote:
> > On Thu, Jan 21, 2021 at 8:09 PM mtk15103 <[email protected]> wrote:
> > >
> > > On Thu, 2021-01-21 at 16:55 +0800, Nicolas Boichat wrote:
> > > > On Thu, Jan 21, 2021 at 3:52 PM Hailong Fan <[email protected]> wrote:
> > > > >
> > > > > When flipping the polarity will be generated interrupt under certain
> > > > > circumstances, but GPIO external signal has not changed.
> > > > > Then, mask the interrupt before polarity setting, and clear the
> > > > > unexpected interrupt after trigger type setting completed.
> > > > >
> > > > > Signed-off-by: Hailong Fan <[email protected]>
> > > > > ---
> > > > > Resend since some server reject.
> > > > > ---
> > > > > drivers/pinctrl/mediatek/mtk-eint.c | 13 +++++++++++--
> > > > > 1 file changed, 11 insertions(+), 2 deletions(-)
> > > > >
> > > > > diff --git a/drivers/pinctrl/mediatek/mtk-eint.c b/drivers/pinctrl/mediatek/mtk-eint.c
> > > > > index 22736f60c16c..3acda6bb401e 100644
> > > > > --- a/drivers/pinctrl/mediatek/mtk-eint.c
> > > > > +++ b/drivers/pinctrl/mediatek/mtk-eint.c
> > > > > @@ -157,6 +157,7 @@ static void mtk_eint_ack(struct irq_data *d)
> > > > > static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
> > > > > {
> > > > > struct mtk_eint *eint = irq_data_get_irq_chip_data(d);
> > > > > + unsigned int unmask;
> > > >
> > > > bool?
> > > Yes,thanks.
> > > >
> > > > > u32 mask = BIT(d->hwirq & 0x1f);
> > > > > void __iomem *reg;
> > > > >
> > > > > @@ -173,6 +174,13 @@ static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
> > > > > else
> > > > > eint->dual_edge[d->hwirq] = 0;
> > > > >
> > > > > + if (!mtk_eint_get_mask(eint, d->hwirq)) {
> > > > > + mtk_eint_mask(d);
> > > > > + unmask = 1;
> > > > > + } else {
> > > > > + unmask = 0;
> > > > > + }
> > > > > +
> > > > > if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_EDGE_FALLING)) {
> > > > > reg = mtk_eint_get_offset(eint, d->hwirq, eint->regs->pol_clr);
> > > > > writel(mask, reg);
> > > > > @@ -189,8 +197,9 @@ static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
> > > > > writel(mask, reg);
> > > > > }
> > > > >
> > > > > - if (eint->dual_edge[d->hwirq])
> > > > > - mtk_eint_flip_edge(eint, d->hwirq);
> > > >
> > > > Why are you dropping this? Aren't we at risk to miss the first edge
> > > > after mtk_eint_set_type is called?
> > > mtk_eint_unmask() will do it.
> > > If unmask != 1, user need to call mtk_eint_unmask() to enable the
> > > interrupt before use it, thanks.
> >
> > Makes sense, I just have one more worry:
> > https://elixir.bootlin.com/linux/latest/source/drivers/pinctrl/mediatek/mtk-eint.c#L122
> >
> > mtk_eint_unmask unmasks the interrupt _before_ the edge is flipped,
> > could this cause a spurious interrupt? On any unmask operation -- not
> > just on mtk_eint_set_type (so this is technically another problem,
> > that should be fixed as a separate patch)
>
> This situation will not happen.
>
> Spurious interrupt occur condition: edge irq polarity value is same with
> input signal.
> e.g.
> Default value: GPIO input is high, trigger type is falling_edge.
> User want modify trigger type is rising_edge under some certain
> circumstances, it will generate spurious interrupt but external signal
> maintain high.
> So we need ack interrupt after trigger_type setting is completed.
>
> mtk_eint_flip_edge is for dual_edge, the polarity setting based on
> current gpio input signal:
> if (input == high)
> polarity = low; /* falling_edge */
> else
> polarity = high; /* rising_edge */
> Then it's not cause a spurious interrupt.
Okay let me try to make sure I follow:
- Say interrupt is currently IRQ_TYPE_EDGE_FALLING (and GPIO is high and stable)
- mtk_eint_set_type(d, IRQ_TYPE_EDGE_BOTH)
- mtk_eint_mask(d)
- (no mask changed, just eint->dual_edge)
- mtk_eint_ack(d) (not actually needed in this example)
- mtk_eint_unmask(d)
- HW reg unmask (can't generate an interrupt as anything that would
have happened is acked already -- even with different previous/new
types than my example)
- flip_edge (will swap polarity as needed but can't generate
interrupt as it won't set the polarity to be the same as the current
GPIO state)
Okay, I think I'm convinced.
Please fix the nits and then you can add
Reviewed-by: Nicolas Boichat <[email protected]>
> > > > > + mtk_eint_ack(d);
> > > > > + if (unmask == 1)
> > > >
> > > > Just `if (unmask)`
> > > Yes,thanks.
> > > > > + mtk_eint_unmask(d);
> > > > >
> > > > > return 0;
> > > > > }
> > > > > --
> > > > > 2.18.0
> > >
>
On Fri, 2021-01-22 at 18:54 +0800, Nicolas Boichat wrote:
> On Fri, Jan 22, 2021 at 10:44 AM mtk15103 <[email protected]> wrote:
> >
> > On Thu, 2021-01-21 at 20:13 +0800, Nicolas Boichat wrote:
> > > On Thu, Jan 21, 2021 at 8:09 PM mtk15103 <[email protected]> wrote:
> > > >
> > > > On Thu, 2021-01-21 at 16:55 +0800, Nicolas Boichat wrote:
> > > > > On Thu, Jan 21, 2021 at 3:52 PM Hailong Fan <[email protected]> wrote:
> > > > > >
> > > > > > When flipping the polarity will be generated interrupt under certain
> > > > > > circumstances, but GPIO external signal has not changed.
> > > > > > Then, mask the interrupt before polarity setting, and clear the
> > > > > > unexpected interrupt after trigger type setting completed.
> > > > > >
> > > > > > Signed-off-by: Hailong Fan <[email protected]>
> > > > > > ---
> > > > > > Resend since some server reject.
> > > > > > ---
> > > > > > drivers/pinctrl/mediatek/mtk-eint.c | 13 +++++++++++--
> > > > > > 1 file changed, 11 insertions(+), 2 deletions(-)
> > > > > >
> > > > > > diff --git a/drivers/pinctrl/mediatek/mtk-eint.c b/drivers/pinctrl/mediatek/mtk-eint.c
> > > > > > index 22736f60c16c..3acda6bb401e 100644
> > > > > > --- a/drivers/pinctrl/mediatek/mtk-eint.c
> > > > > > +++ b/drivers/pinctrl/mediatek/mtk-eint.c
> > > > > > @@ -157,6 +157,7 @@ static void mtk_eint_ack(struct irq_data *d)
> > > > > > static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
> > > > > > {
> > > > > > struct mtk_eint *eint = irq_data_get_irq_chip_data(d);
> > > > > > + unsigned int unmask;
> > > > >
> > > > > bool?
> > > > Yes,thanks.
> > > > >
> > > > > > u32 mask = BIT(d->hwirq & 0x1f);
> > > > > > void __iomem *reg;
> > > > > >
> > > > > > @@ -173,6 +174,13 @@ static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
> > > > > > else
> > > > > > eint->dual_edge[d->hwirq] = 0;
> > > > > >
> > > > > > + if (!mtk_eint_get_mask(eint, d->hwirq)) {
> > > > > > + mtk_eint_mask(d);
> > > > > > + unmask = 1;
> > > > > > + } else {
> > > > > > + unmask = 0;
> > > > > > + }
> > > > > > +
> > > > > > if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_EDGE_FALLING)) {
> > > > > > reg = mtk_eint_get_offset(eint, d->hwirq, eint->regs->pol_clr);
> > > > > > writel(mask, reg);
> > > > > > @@ -189,8 +197,9 @@ static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
> > > > > > writel(mask, reg);
> > > > > > }
> > > > > >
> > > > > > - if (eint->dual_edge[d->hwirq])
> > > > > > - mtk_eint_flip_edge(eint, d->hwirq);
> > > > >
> > > > > Why are you dropping this? Aren't we at risk to miss the first edge
> > > > > after mtk_eint_set_type is called?
> > > > mtk_eint_unmask() will do it.
> > > > If unmask != 1, user need to call mtk_eint_unmask() to enable the
> > > > interrupt before use it, thanks.
> > >
> > > Makes sense, I just have one more worry:
> > > https://elixir.bootlin.com/linux/latest/source/drivers/pinctrl/mediatek/mtk-eint.c#L122
> > >
> > > mtk_eint_unmask unmasks the interrupt _before_ the edge is flipped,
> > > could this cause a spurious interrupt? On any unmask operation -- not
> > > just on mtk_eint_set_type (so this is technically another problem,
> > > that should be fixed as a separate patch)
> >
> > This situation will not happen.
> >
> > Spurious interrupt occur condition: edge irq polarity value is same with
> > input signal.
> > e.g.
> > Default value: GPIO input is high, trigger type is falling_edge.
> > User want modify trigger type is rising_edge under some certain
> > circumstances, it will generate spurious interrupt but external signal
> > maintain high.
> > So we need ack interrupt after trigger_type setting is completed.
> >
> > mtk_eint_flip_edge is for dual_edge, the polarity setting based on
> > current gpio input signal:
> > if (input == high)
> > polarity = low; /* falling_edge */
> > else
> > polarity = high; /* rising_edge */
> > Then it's not cause a spurious interrupt.
>
> Okay let me try to make sure I follow:
>
> - Say interrupt is currently IRQ_TYPE_EDGE_FALLING (and GPIO is high and stable)
> - mtk_eint_set_type(d, IRQ_TYPE_EDGE_BOTH)
> - mtk_eint_mask(d)
> - (no mask changed, just eint->dual_edge)
> - mtk_eint_ack(d) (not actually needed in this example)
> - mtk_eint_unmask(d)
> - HW reg unmask (can't generate an interrupt as anything that would
> have happened is acked already -- even with different previous/new
> types than my example)
> - flip_edge (will swap polarity as needed but can't generate
> interrupt as it won't set the polarity to be the same as the current
> GPIO state)
>
> Okay, I think I'm convinced.
>
> Please fix the nits and then you can add
Thanks a lot for your comments.
V2 patch has been sent to you, please help review it, thx.
>
> Reviewed-by: Nicolas Boichat <[email protected]>
>
> > > > > > + mtk_eint_ack(d);
> > > > > > + if (unmask == 1)
> > > > >
> > > > > Just `if (unmask)`
> > > > Yes,thanks.
> > > > > > + mtk_eint_unmask(d);
> > > > > >
> > > > > > return 0;
> > > > > > }
> > > > > > --
> > > > > > 2.18.0
> > > >
> >