[1/3] drivers: thermal: tsens: Add critical interrupt support
diff mbox series

Message ID 4b949a4f401a7f9d403ed0f0c16c7feb083f3524.1573499020.git.amit.kucheria@linaro.org
State New
Delegated to: Eduardo Valentin
Headers show
Series
  • thermal: tsens: Handle critical interrupts
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Commit Message

Amit Kucheria Nov. 11, 2019, 7:21 p.m. UTC
TSENS IP v2.x adds critical threshold interrupt support for each sensor
in addition to the upper/lower threshold interrupt. Add support in the
driver.

Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
---
 drivers/thermal/qcom/tsens-common.c | 129 ++++++++++++++++++++++++++--
 drivers/thermal/qcom/tsens-v2.c     |   8 +-
 drivers/thermal/qcom/tsens.c        |  21 +++++
 drivers/thermal/qcom/tsens.h        |  73 ++++++++++++++++
 4 files changed, 220 insertions(+), 11 deletions(-)

Comments

Bjorn Andersson Nov. 12, 2019, 7:38 p.m. UTC | #1
On Mon 11 Nov 11:21 PST 2019, Amit Kucheria wrote:

> TSENS IP v2.x adds critical threshold interrupt support for each sensor
> in addition to the upper/lower threshold interrupt. Add support in the
> driver.
> 
> Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
> ---
>  drivers/thermal/qcom/tsens-common.c | 129 ++++++++++++++++++++++++++--
>  drivers/thermal/qcom/tsens-v2.c     |   8 +-
>  drivers/thermal/qcom/tsens.c        |  21 +++++
>  drivers/thermal/qcom/tsens.h        |  73 ++++++++++++++++
>  4 files changed, 220 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/thermal/qcom/tsens-common.c b/drivers/thermal/qcom/tsens-common.c
> index 4359a4247ac3..2989cb952cdb 100644
> --- a/drivers/thermal/qcom/tsens-common.c
> +++ b/drivers/thermal/qcom/tsens-common.c
> @@ -23,6 +23,10 @@
>   * @low_thresh:     lower threshold temperature value
>   * @low_irq_mask:   mask register for lower threshold irqs
>   * @low_irq_clear:  clear register for lower threshold irqs
> + * @crit_viol:      critical threshold violated

"violated" as in "temperature is above crit_thresh"?

> + * @crit_thresh:    critical threshold temperature value
> + * @crit_irq_mask:  mask register for critical threshold irqs
> + * @crit_irq_clear: clear register for critical threshold irqs
>   *
[..]
> diff --git a/drivers/thermal/qcom/tsens.c b/drivers/thermal/qcom/tsens.c
> index 7d317660211e..784c4976c4f9 100644
> --- a/drivers/thermal/qcom/tsens.c
> +++ b/drivers/thermal/qcom/tsens.c
> @@ -121,6 +121,27 @@ static int tsens_register(struct tsens_priv *priv)
>  
>  	enable_irq_wake(irq);
>  
> +	if (tsens_version(priv) > VER_1_X) {
> +		irq = platform_get_irq_byname(pdev, "critical");
> +		if (irq < 0) {

Treating this as a fatal error breaks backwards compatibility with
current devicetree; and even within your patch series, tsens should fail
to probe between this patch and the application of patch 3.

Please flip this around and do:

irq = platform_get_irq_byname(pdev, "critical");
if (irq >= 0 && tsens_version(priv) > VER_1_X) {
	request_irq()...
}

> +			ret = irq;
> +			goto err_put_device;
> +		}
> +
> +		ret = devm_request_threaded_irq(&pdev->dev, irq,
> +						NULL, tsens_critical_irq_thread,
> +						IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
> +						dev_name(&pdev->dev), priv);
> +		if (ret) {
> +			dev_err(&pdev->dev, "%s: failed to get critical irq\n", __func__);
> +			goto err_put_device;
> +		}
> +
> +		enable_irq_wake(irq);
> +	}
> +
> +	return 0;
> +
>  err_put_device:
>  	put_device(&pdev->dev);
>  	return ret;

Regards,
Bjorn
Stephen Boyd Nov. 14, 2019, 10:50 p.m. UTC | #2
Quoting Amit Kucheria (2019-11-11 11:21:27)
> diff --git a/drivers/thermal/qcom/tsens-common.c b/drivers/thermal/qcom/tsens-common.c
> index 4359a4247ac3..2989cb952cdb 100644
> --- a/drivers/thermal/qcom/tsens-common.c
> +++ b/drivers/thermal/qcom/tsens-common.c
> @@ -321,6 +357,65 @@ static inline u32 masked_irq(u32 hw_id, u32 mask, enum tsens_ver ver)
>         return 0;
>  }
>  
> +/**
> + * tsens_critical_irq_thread - Threaded interrupt handler for critical interrupts
> + * @irq: irq number
> + * @data: tsens controller private data
> + *
> + * Check all sensors to find ones that violated their critical threshold limits.
> + * Clear and then re-enable the interrupt.
> + *
> + * The level-triggered interrupt might deassert if the temperature returned to
> + * within the threshold limits by the time the handler got scheduled. We
> + * consider the irq to have been handled in that case.
> + *
> + * Return: IRQ_HANDLED
> + */
> +irqreturn_t tsens_critical_irq_thread(int irq, void *data)
> +{
> +       struct tsens_priv *priv = data;
> +       struct tsens_irq_data d;
> +       bool enable = true, disable = false;

Why not just use true and false in the one place these variables are
used?

> +       unsigned long flags;
> +       int temp, ret, i;
> +
> +       for (i = 0; i < priv->num_sensors; i++) {
> +               struct tsens_sensor *s = &priv->sensor[i];

Maybe make this const?

> +               u32 hw_id = s->hw_id;
> +
> +               if (IS_ERR(priv->sensor[i].tzd))

IS_ERR(s->tzd)?

> +                       continue;
> +               if (!tsens_threshold_violated(priv, hw_id, &d))
> +                       continue;
> +               ret = get_temp_tsens_valid(s, &temp);

Can this accept a const 's'?

> +               if (ret) {
> +                       dev_err(priv->dev, "[%u] %s: error reading sensor\n", hw_id, __func__);
> +                       continue;
> +               }
> +
> +               spin_lock_irqsave(&priv->ul_lock, flags);
> +
> +               tsens_read_irq_state(priv, hw_id, s, &d);
> +
> +               if (d.crit_viol &&
> +                   !masked_irq(hw_id, d.crit_irq_mask, tsens_version(priv))) {
> +                       tsens_set_interrupt(priv, hw_id, CRITICAL, disable);
> +                       if (d.crit_thresh > temp) {
> +                               dev_dbg(priv->dev, "[%u] %s: re-arm upper\n",
> +                                       priv->sensor[i].hw_id, __func__);

hw_id instead of priv->sensor...?

> +                       } else {
> +                               dev_dbg(priv->dev, "[%u] %s: TZ update trigger (%d mC)\n",
> +                                       hw_id, __func__, temp);
> +                       }
> +                       tsens_set_interrupt(priv, hw_id, CRITICAL, enable);
> +               }
> +
> +               spin_unlock_irqrestore(&priv->crit_lock, flags);
> +       }
> +
> +       return IRQ_HANDLED;
> +}
> +
>  /**
>   * tsens_irq_thread - Threaded interrupt handler for uplow interrupts
>   * @irq: irq number
> diff --git a/drivers/thermal/qcom/tsens.c b/drivers/thermal/qcom/tsens.c
> index 7d317660211e..784c4976c4f9 100644
> --- a/drivers/thermal/qcom/tsens.c
> +++ b/drivers/thermal/qcom/tsens.c
> @@ -121,6 +121,27 @@ static int tsens_register(struct tsens_priv *priv)
>  
>         enable_irq_wake(irq);
>  
> +       if (tsens_version(priv) > VER_1_X) {
> +               irq = platform_get_irq_byname(pdev, "critical");
> +               if (irq < 0) {
> +                       ret = irq;
> +                       goto err_put_device;
> +               }
> +
> +               ret = devm_request_threaded_irq(&pdev->dev, irq,
> +                                               NULL, tsens_critical_irq_thread,
> +                                               IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
> +                                               dev_name(&pdev->dev), priv);
> +               if (ret) {
> +                       dev_err(&pdev->dev, "%s: failed to get critical irq\n", __func__);
> +                       goto err_put_device;

Do we need to disable_irq_wake() for the previous irq here?

> +               }
> +
> +               enable_irq_wake(irq);
> +       }
> +
> +       return 0;
> +
>  err_put_device:
>         put_device(&pdev->dev);
>         return ret;
Amit Kucheria Nov. 28, 2019, 6:46 p.m. UTC | #3
On Wed, Nov 13, 2019 at 1:08 AM Bjorn Andersson
<bjorn.andersson@linaro.org> wrote:
>
> On Mon 11 Nov 11:21 PST 2019, Amit Kucheria wrote:
>
> > TSENS IP v2.x adds critical threshold interrupt support for each sensor
> > in addition to the upper/lower threshold interrupt. Add support in the
> > driver.
> >
> > Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
> > ---
> >  drivers/thermal/qcom/tsens-common.c | 129 ++++++++++++++++++++++++++--
> >  drivers/thermal/qcom/tsens-v2.c     |   8 +-
> >  drivers/thermal/qcom/tsens.c        |  21 +++++
> >  drivers/thermal/qcom/tsens.h        |  73 ++++++++++++++++
> >  4 files changed, 220 insertions(+), 11 deletions(-)
> >
> > diff --git a/drivers/thermal/qcom/tsens-common.c b/drivers/thermal/qcom/tsens-common.c
> > index 4359a4247ac3..2989cb952cdb 100644
> > --- a/drivers/thermal/qcom/tsens-common.c
> > +++ b/drivers/thermal/qcom/tsens-common.c
> > @@ -23,6 +23,10 @@
> >   * @low_thresh:     lower threshold temperature value
> >   * @low_irq_mask:   mask register for lower threshold irqs
> >   * @low_irq_clear:  clear register for lower threshold irqs
> > + * @crit_viol:      critical threshold violated
>
> "violated" as in "temperature is above crit_thresh"?

Yes.

>
> > + * @crit_thresh:    critical threshold temperature value
> > + * @crit_irq_mask:  mask register for critical threshold irqs
> > + * @crit_irq_clear: clear register for critical threshold irqs
> >   *
> [..]
> > diff --git a/drivers/thermal/qcom/tsens.c b/drivers/thermal/qcom/tsens.c
> > index 7d317660211e..784c4976c4f9 100644
> > --- a/drivers/thermal/qcom/tsens.c
> > +++ b/drivers/thermal/qcom/tsens.c
> > @@ -121,6 +121,27 @@ static int tsens_register(struct tsens_priv *priv)
> >
> >       enable_irq_wake(irq);
> >
> > +     if (tsens_version(priv) > VER_1_X) {
> > +             irq = platform_get_irq_byname(pdev, "critical");
> > +             if (irq < 0) {
>
> Treating this as a fatal error breaks backwards compatibility with
> current devicetree; and even within your patch series, tsens should fail
> to probe between this patch and the application of patch 3.

Good catch.

> Please flip this around and do:
>
> irq = platform_get_irq_byname(pdev, "critical");
> if (irq >= 0 && tsens_version(priv) > VER_1_X) {
>         request_irq()...
> }

Won't this still break with current devicetree since irq < 0 until
patch 3? Or are you saying we shouldn't check for
platform_get_irq_byname() failure?

I can see two ways out:
1. We patch the dtsi before the code change.
2. We make critical interrupt failure non-fatal by just printing some
messages and still returning success.

Regards,
Amit


> > +                     ret = irq;
> > +                     goto err_put_device;
> > +             }
> > +
> > +             ret = devm_request_threaded_irq(&pdev->dev, irq,
> > +                                             NULL, tsens_critical_irq_thread,
> > +                                             IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
> > +                                             dev_name(&pdev->dev), priv);
> > +             if (ret) {
> > +                     dev_err(&pdev->dev, "%s: failed to get critical irq\n", __func__);
> > +                     goto err_put_device;
> > +             }
> > +
> > +             enable_irq_wake(irq);
> > +     }
> > +
> > +     return 0;
> > +
> >  err_put_device:
> >       put_device(&pdev->dev);
> >       return ret;
>
> Regards,
> Bjorn
Bjorn Andersson Nov. 28, 2019, 9:43 p.m. UTC | #4
On Thu 28 Nov 10:46 PST 2019, Amit Kucheria wrote:

> On Wed, Nov 13, 2019 at 1:08 AM Bjorn Andersson
> <bjorn.andersson@linaro.org> wrote:
> >
> > On Mon 11 Nov 11:21 PST 2019, Amit Kucheria wrote:
> >
> > > TSENS IP v2.x adds critical threshold interrupt support for each sensor
> > > in addition to the upper/lower threshold interrupt. Add support in the
> > > driver.
> > >
> > > Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
> > > ---
> > >  drivers/thermal/qcom/tsens-common.c | 129 ++++++++++++++++++++++++++--
> > >  drivers/thermal/qcom/tsens-v2.c     |   8 +-
> > >  drivers/thermal/qcom/tsens.c        |  21 +++++
> > >  drivers/thermal/qcom/tsens.h        |  73 ++++++++++++++++
> > >  4 files changed, 220 insertions(+), 11 deletions(-)
> > >
> > > diff --git a/drivers/thermal/qcom/tsens-common.c b/drivers/thermal/qcom/tsens-common.c
> > > index 4359a4247ac3..2989cb952cdb 100644
> > > --- a/drivers/thermal/qcom/tsens-common.c
> > > +++ b/drivers/thermal/qcom/tsens-common.c
> > > @@ -23,6 +23,10 @@
> > >   * @low_thresh:     lower threshold temperature value
> > >   * @low_irq_mask:   mask register for lower threshold irqs
> > >   * @low_irq_clear:  clear register for lower threshold irqs
> > > + * @crit_viol:      critical threshold violated
> >
> > "violated" as in "temperature is above crit_thresh"?
> 
> Yes.
> 
> >
> > > + * @crit_thresh:    critical threshold temperature value
> > > + * @crit_irq_mask:  mask register for critical threshold irqs
> > > + * @crit_irq_clear: clear register for critical threshold irqs
> > >   *
> > [..]
> > > diff --git a/drivers/thermal/qcom/tsens.c b/drivers/thermal/qcom/tsens.c
> > > index 7d317660211e..784c4976c4f9 100644
> > > --- a/drivers/thermal/qcom/tsens.c
> > > +++ b/drivers/thermal/qcom/tsens.c
> > > @@ -121,6 +121,27 @@ static int tsens_register(struct tsens_priv *priv)
> > >
> > >       enable_irq_wake(irq);
> > >
> > > +     if (tsens_version(priv) > VER_1_X) {
> > > +             irq = platform_get_irq_byname(pdev, "critical");
> > > +             if (irq < 0) {
> >
> > Treating this as a fatal error breaks backwards compatibility with
> > current devicetree; and even within your patch series, tsens should fail
> > to probe between this patch and the application of patch 3.
> 
> Good catch.
> 
> > Please flip this around and do:
> >
> > irq = platform_get_irq_byname(pdev, "critical");
> > if (irq >= 0 && tsens_version(priv) > VER_1_X) {
> >         request_irq()...
> > }
> 
> Won't this still break with current devicetree since irq < 0 until
> patch 3? Or are you saying we shouldn't check for
> platform_get_irq_byname() failure?
> 

I'm trying to say that dtsi without "critical" defined should cause the
driver to simply skip this segment, not fail to initialize.

> I can see two ways out:
> 1. We patch the dtsi before the code change.

You're expected to maintain backwards compatibility with existing dtb
files out there. The support for critical interrupt is an additional
feature, so you should be able to do this by detecting if "critical" is
defined (e.g. by checking the return value of
platform_get_irq_byname()).

> 2. We make critical interrupt failure non-fatal by just printing some
> messages and still returning success.
> 

Try to make it as specific as possible (without adding a bunch of code)
and throw in a dev_info() if no "critical" is found.

Regards,
Bjorn

> Regards,
> Amit
> 
> 
> > > +                     ret = irq;
> > > +                     goto err_put_device;
> > > +             }
> > > +
> > > +             ret = devm_request_threaded_irq(&pdev->dev, irq,
> > > +                                             NULL, tsens_critical_irq_thread,
> > > +                                             IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
> > > +                                             dev_name(&pdev->dev), priv);
> > > +             if (ret) {
> > > +                     dev_err(&pdev->dev, "%s: failed to get critical irq\n", __func__);
> > > +                     goto err_put_device;
> > > +             }
> > > +
> > > +             enable_irq_wake(irq);
> > > +     }
> > > +
> > > +     return 0;
> > > +
> > >  err_put_device:
> > >       put_device(&pdev->dev);
> > >       return ret;
> >
> > Regards,
> > Bjorn
Amit Kucheria Dec. 3, 2019, 4:57 a.m. UTC | #5
On Fri, Nov 15, 2019 at 4:20 AM Stephen Boyd <swboyd@chromium.org> wrote:
>
> Quoting Amit Kucheria (2019-11-11 11:21:27)
> > diff --git a/drivers/thermal/qcom/tsens-common.c b/drivers/thermal/qcom/tsens-common.c
> > index 4359a4247ac3..2989cb952cdb 100644
> > --- a/drivers/thermal/qcom/tsens-common.c
> > +++ b/drivers/thermal/qcom/tsens-common.c
> > @@ -321,6 +357,65 @@ static inline u32 masked_irq(u32 hw_id, u32 mask, enum tsens_ver ver)
> >         return 0;
> >  }
> >
> > +/**
> > + * tsens_critical_irq_thread - Threaded interrupt handler for critical interrupts
> > + * @irq: irq number
> > + * @data: tsens controller private data
> > + *
> > + * Check all sensors to find ones that violated their critical threshold limits.
> > + * Clear and then re-enable the interrupt.
> > + *
> > + * The level-triggered interrupt might deassert if the temperature returned to
> > + * within the threshold limits by the time the handler got scheduled. We
> > + * consider the irq to have been handled in that case.
> > + *
> > + * Return: IRQ_HANDLED
> > + */
> > +irqreturn_t tsens_critical_irq_thread(int irq, void *data)
> > +{
> > +       struct tsens_priv *priv = data;
> > +       struct tsens_irq_data d;
> > +       bool enable = true, disable = false;
>
> Why not just use true and false in the one place these variables are
> used?

Will fix.

> > +       unsigned long flags;
> > +       int temp, ret, i;
> > +
> > +       for (i = 0; i < priv->num_sensors; i++) {
> > +               struct tsens_sensor *s = &priv->sensor[i];
>
> Maybe make this const?

OK.

>
> > +               u32 hw_id = s->hw_id;
> > +
> > +               if (IS_ERR(priv->sensor[i].tzd))
>
> IS_ERR(s->tzd)?

Yup.

>
> > +                       continue;
> > +               if (!tsens_threshold_violated(priv, hw_id, &d))
> > +                       continue;
> > +               ret = get_temp_tsens_valid(s, &temp);
>
> Can this accept a const 's'?

Yes.

> > +               if (ret) {
> > +                       dev_err(priv->dev, "[%u] %s: error reading sensor\n", hw_id, __func__);
> > +                       continue;
> > +               }
> > +
> > +               spin_lock_irqsave(&priv->ul_lock, flags);
> > +
> > +               tsens_read_irq_state(priv, hw_id, s, &d);
> > +
> > +               if (d.crit_viol &&
> > +                   !masked_irq(hw_id, d.crit_irq_mask, tsens_version(priv))) {
> > +                       tsens_set_interrupt(priv, hw_id, CRITICAL, disable);
> > +                       if (d.crit_thresh > temp) {
> > +                               dev_dbg(priv->dev, "[%u] %s: re-arm upper\n",
> > +                                       priv->sensor[i].hw_id, __func__);
>
> hw_id instead of priv->sensor...?

Done. Will fixup for older code in a separate patch.

> > +                       } else {
> > +                               dev_dbg(priv->dev, "[%u] %s: TZ update trigger (%d mC)\n",
> > +                                       hw_id, __func__, temp);
> > +                       }
> > +                       tsens_set_interrupt(priv, hw_id, CRITICAL, enable);
> > +               }
> > +
> > +               spin_unlock_irqrestore(&priv->crit_lock, flags);
> > +       }
> > +
> > +       return IRQ_HANDLED;
> > +}
> > +
> >  /**
> >   * tsens_irq_thread - Threaded interrupt handler for uplow interrupts
> >   * @irq: irq number
> > diff --git a/drivers/thermal/qcom/tsens.c b/drivers/thermal/qcom/tsens.c
> > index 7d317660211e..784c4976c4f9 100644
> > --- a/drivers/thermal/qcom/tsens.c
> > +++ b/drivers/thermal/qcom/tsens.c
> > @@ -121,6 +121,27 @@ static int tsens_register(struct tsens_priv *priv)
> >
> >         enable_irq_wake(irq);
> >
> > +       if (tsens_version(priv) > VER_1_X) {
> > +               irq = platform_get_irq_byname(pdev, "critical");
> > +               if (irq < 0) {
> > +                       ret = irq;
> > +                       goto err_put_device;
> > +               }
> > +
> > +               ret = devm_request_threaded_irq(&pdev->dev, irq,
> > +                                               NULL, tsens_critical_irq_thread,
> > +                                               IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
> > +                                               dev_name(&pdev->dev), priv);
> > +               if (ret) {
> > +                       dev_err(&pdev->dev, "%s: failed to get critical irq\n", __func__);
> > +                       goto err_put_device;
>
> Do we need to disable_irq_wake() for the previous irq here?

Or we could just move the earlier enable_irq_wake() to after
successful registration of the critical interrupt to avoid the error
branch. See v2 posting.



> > +               }
> > +
> > +               enable_irq_wake(irq);
> > +       }
> > +
> > +       return 0;
> > +
> >  err_put_device:
> >         put_device(&pdev->dev);
> >         return ret;
Amit Kucheria Dec. 3, 2019, 5:02 a.m. UTC | #6
On Fri, Nov 29, 2019 at 3:13 AM Bjorn Andersson
<bjorn.andersson@linaro.org> wrote:
>
> On Thu 28 Nov 10:46 PST 2019, Amit Kucheria wrote:
>
> > On Wed, Nov 13, 2019 at 1:08 AM Bjorn Andersson
> > <bjorn.andersson@linaro.org> wrote:
> > >
> > > On Mon 11 Nov 11:21 PST 2019, Amit Kucheria wrote:
> > >
> > > > TSENS IP v2.x adds critical threshold interrupt support for each sensor
> > > > in addition to the upper/lower threshold interrupt. Add support in the
> > > > driver.
> > > >
> > > > Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
> > > > ---
> > > >  drivers/thermal/qcom/tsens-common.c | 129 ++++++++++++++++++++++++++--
> > > >  drivers/thermal/qcom/tsens-v2.c     |   8 +-
> > > >  drivers/thermal/qcom/tsens.c        |  21 +++++
> > > >  drivers/thermal/qcom/tsens.h        |  73 ++++++++++++++++
> > > >  4 files changed, 220 insertions(+), 11 deletions(-)
> > > >
> > > > diff --git a/drivers/thermal/qcom/tsens-common.c b/drivers/thermal/qcom/tsens-common.c
> > > > index 4359a4247ac3..2989cb952cdb 100644
> > > > --- a/drivers/thermal/qcom/tsens-common.c
> > > > +++ b/drivers/thermal/qcom/tsens-common.c
> > > > @@ -23,6 +23,10 @@
> > > >   * @low_thresh:     lower threshold temperature value
> > > >   * @low_irq_mask:   mask register for lower threshold irqs
> > > >   * @low_irq_clear:  clear register for lower threshold irqs
> > > > + * @crit_viol:      critical threshold violated
> > >
> > > "violated" as in "temperature is above crit_thresh"?
> >
> > Yes.
> >
> > >
> > > > + * @crit_thresh:    critical threshold temperature value
> > > > + * @crit_irq_mask:  mask register for critical threshold irqs
> > > > + * @crit_irq_clear: clear register for critical threshold irqs
> > > >   *
> > > [..]
> > > > diff --git a/drivers/thermal/qcom/tsens.c b/drivers/thermal/qcom/tsens.c
> > > > index 7d317660211e..784c4976c4f9 100644
> > > > --- a/drivers/thermal/qcom/tsens.c
> > > > +++ b/drivers/thermal/qcom/tsens.c
> > > > @@ -121,6 +121,27 @@ static int tsens_register(struct tsens_priv *priv)
> > > >
> > > >       enable_irq_wake(irq);
> > > >
> > > > +     if (tsens_version(priv) > VER_1_X) {
> > > > +             irq = platform_get_irq_byname(pdev, "critical");
> > > > +             if (irq < 0) {
> > >
> > > Treating this as a fatal error breaks backwards compatibility with
> > > current devicetree; and even within your patch series, tsens should fail
> > > to probe between this patch and the application of patch 3.
> >
> > Good catch.
> >
> > > Please flip this around and do:
> > >
> > > irq = platform_get_irq_byname(pdev, "critical");
> > > if (irq >= 0 && tsens_version(priv) > VER_1_X) {
> > >         request_irq()...
> > > }
> >
> > Won't this still break with current devicetree since irq < 0 until
> > patch 3? Or are you saying we shouldn't check for
> > platform_get_irq_byname() failure?
> >
>
> I'm trying to say that dtsi without "critical" defined should cause the
> driver to simply skip this segment, not fail to initialize.
>
> > I can see two ways out:
> > 1. We patch the dtsi before the code change.
>
> You're expected to maintain backwards compatibility with existing dtb
> files out there. The support for critical interrupt is an additional
> feature, so you should be able to do this by detecting if "critical" is
> defined (e.g. by checking the return value of
> platform_get_irq_byname()).
>
> > 2. We make critical interrupt failure non-fatal by just printing some
> > messages and still returning success.
> >
>
> Try to make it as specific as possible (without adding a bunch of code)
> and throw in a dev_info() if no "critical" is found.

I believe I have now addressed the problem in v2 explicitly overriding
the return value in case of failure in the critical interrupt irq
setup path and simply printing a warning.

In hindsight, critical interrupt support should've been added in the
same series as uplow interrupt support so avoid having to support
"intermediate" DTS file state for one kernel version.

Regards,
Amit

Patch
diff mbox series

diff --git a/drivers/thermal/qcom/tsens-common.c b/drivers/thermal/qcom/tsens-common.c
index 4359a4247ac3..2989cb952cdb 100644
--- a/drivers/thermal/qcom/tsens-common.c
+++ b/drivers/thermal/qcom/tsens-common.c
@@ -23,6 +23,10 @@ 
  * @low_thresh:     lower threshold temperature value
  * @low_irq_mask:   mask register for lower threshold irqs
  * @low_irq_clear:  clear register for lower threshold irqs
+ * @crit_viol:      critical threshold violated
+ * @crit_thresh:    critical threshold temperature value
+ * @crit_irq_mask:  mask register for critical threshold irqs
+ * @crit_irq_clear: clear register for critical threshold irqs
  *
  * Structure containing data about temperature threshold settings and
  * irq status if they were violated.
@@ -36,6 +40,10 @@  struct tsens_irq_data {
 	int low_thresh;
 	u32 low_irq_mask;
 	u32 low_irq_clear;
+	u32 crit_viol;
+	u32 crit_thresh;
+	u32 crit_irq_mask;
+	u32 crit_irq_clear;
 };
 
 char *qfprom_read(struct device *dev, const char *cname)
@@ -172,7 +180,7 @@  static int tsens_mC_to_hw(struct tsens_sensor *s, int temp)
 	return temp / 100;
 }
 
-static inline enum tsens_ver tsens_version(struct tsens_priv *priv)
+enum tsens_ver tsens_version(struct tsens_priv *priv)
 {
 	return priv->feat->ver_major;
 }
@@ -189,6 +197,9 @@  static void tsens_set_interrupt_v1(struct tsens_priv *priv, u32 hw_id,
 	case LOWER:
 		index = LOW_INT_CLEAR_0 + hw_id;
 		break;
+	case CRITICAL:
+		/* No critical interrupts before v2 */
+		break;
 	}
 	regmap_field_write(priv->rf[index], enable ? 0 : 1);
 }
@@ -214,6 +225,10 @@  static void tsens_set_interrupt_v2(struct tsens_priv *priv, u32 hw_id,
 		index_mask  = LOW_INT_MASK_0 + hw_id;
 		index_clear = LOW_INT_CLEAR_0 + hw_id;
 		break;
+	case CRITICAL:
+		index_mask  = CRIT_INT_MASK_0 + hw_id;
+		index_clear = CRIT_INT_CLEAR_0 + hw_id;
+		break;
 	}
 
 	if (enable) {
@@ -268,7 +283,14 @@  static int tsens_threshold_violated(struct tsens_priv *priv, u32 hw_id,
 	ret = regmap_field_read(priv->rf[LOWER_STATUS_0 + hw_id], &d->low_viol);
 	if (ret)
 		return ret;
-	if (d->up_viol || d->low_viol)
+
+	if (tsens_version(priv) > VER_1_X) {
+		ret = regmap_field_read(priv->rf[CRITICAL_STATUS_0 + hw_id], &d->crit_viol);
+		if (ret)
+			return ret;
+	}
+
+	if (d->up_viol || d->low_viol || d->crit_viol)
 		return 1;
 
 	return 0;
@@ -292,22 +314,36 @@  static int tsens_read_irq_state(struct tsens_priv *priv, u32 hw_id,
 		ret = regmap_field_read(priv->rf[LOW_INT_MASK_0 + hw_id], &d->low_irq_mask);
 		if (ret)
 			return ret;
+		ret = regmap_field_read(priv->rf[CRIT_INT_CLEAR_0 + hw_id], &d->crit_irq_clear);
+		if (ret)
+			return ret;
+		ret = regmap_field_read(priv->rf[CRIT_INT_MASK_0 + hw_id], &d->crit_irq_mask);
+		if (ret)
+			return ret;
+
+		d->crit_thresh = tsens_hw_to_mC(s, CRIT_THRESH_0 + hw_id);
 	} else {
 		/* No mask register on older TSENS */
 		d->up_irq_mask = 0;
 		d->low_irq_mask = 0;
+		d->crit_irq_clear = 0;
+		d->crit_irq_mask = 0;
+		d->crit_thresh = 0;
 	}
 
 	d->up_thresh  = tsens_hw_to_mC(s, UP_THRESH_0 + hw_id);
 	d->low_thresh = tsens_hw_to_mC(s, LOW_THRESH_0 + hw_id);
 
-	dev_dbg(priv->dev, "[%u] %s%s: status(%u|%u) | clr(%u|%u) | mask(%u|%u)\n",
-		hw_id, __func__, (d->up_viol || d->low_viol) ? "(V)" : "",
-		d->low_viol, d->up_viol, d->low_irq_clear, d->up_irq_clear,
-		d->low_irq_mask, d->up_irq_mask);
-	dev_dbg(priv->dev, "[%u] %s%s: thresh: (%d:%d)\n", hw_id, __func__,
-		(d->up_viol || d->low_viol) ? "(violation)" : "",
-		d->low_thresh, d->up_thresh);
+	dev_dbg(priv->dev, "[%u] %s%s: status(%u|%u|%u) |"
+		" clr(%u|%u|%u) | mask(%u|%u|%u)\n",
+		hw_id, __func__,
+		(d->up_viol || d->low_viol || d->crit_viol) ? "(V)" : "",
+		d->low_viol, d->up_viol, d->crit_viol,
+		d->low_irq_clear, d->up_irq_clear, d->crit_irq_clear,
+		d->low_irq_mask, d->up_irq_mask, d->crit_irq_mask);
+	dev_dbg(priv->dev, "[%u] %s%s: thresh: (%d:%d:%d)\n", hw_id, __func__,
+		(d->up_viol || d->low_viol || d->crit_viol) ? "(V)" : "",
+		d->low_thresh, d->up_thresh, d->crit_thresh);
 
 	return 0;
 }
@@ -321,6 +357,65 @@  static inline u32 masked_irq(u32 hw_id, u32 mask, enum tsens_ver ver)
 	return 0;
 }
 
+/**
+ * tsens_critical_irq_thread - Threaded interrupt handler for critical interrupts
+ * @irq: irq number
+ * @data: tsens controller private data
+ *
+ * Check all sensors to find ones that violated their critical threshold limits.
+ * Clear and then re-enable the interrupt.
+ *
+ * The level-triggered interrupt might deassert if the temperature returned to
+ * within the threshold limits by the time the handler got scheduled. We
+ * consider the irq to have been handled in that case.
+ *
+ * Return: IRQ_HANDLED
+ */
+irqreturn_t tsens_critical_irq_thread(int irq, void *data)
+{
+	struct tsens_priv *priv = data;
+	struct tsens_irq_data d;
+	bool enable = true, disable = false;
+	unsigned long flags;
+	int temp, ret, i;
+
+	for (i = 0; i < priv->num_sensors; i++) {
+		struct tsens_sensor *s = &priv->sensor[i];
+		u32 hw_id = s->hw_id;
+
+		if (IS_ERR(priv->sensor[i].tzd))
+			continue;
+		if (!tsens_threshold_violated(priv, hw_id, &d))
+			continue;
+		ret = get_temp_tsens_valid(s, &temp);
+		if (ret) {
+			dev_err(priv->dev, "[%u] %s: error reading sensor\n", hw_id, __func__);
+			continue;
+		}
+
+		spin_lock_irqsave(&priv->ul_lock, flags);
+
+		tsens_read_irq_state(priv, hw_id, s, &d);
+
+		if (d.crit_viol &&
+		    !masked_irq(hw_id, d.crit_irq_mask, tsens_version(priv))) {
+			tsens_set_interrupt(priv, hw_id, CRITICAL, disable);
+			if (d.crit_thresh > temp) {
+				dev_dbg(priv->dev, "[%u] %s: re-arm upper\n",
+					priv->sensor[i].hw_id, __func__);
+			} else {
+				dev_dbg(priv->dev, "[%u] %s: TZ update trigger (%d mC)\n",
+					hw_id, __func__, temp);
+			}
+			tsens_set_interrupt(priv, hw_id, CRITICAL, enable);
+		}
+
+		spin_unlock_irqrestore(&priv->crit_lock, flags);
+	}
+
+	return IRQ_HANDLED;
+}
+
 /**
  * tsens_irq_thread - Threaded interrupt handler for uplow interrupts
  * @irq: irq number
@@ -683,6 +778,22 @@  int __init init_common(struct tsens_priv *priv)
 		}
 	}
 
+	if (tsens_version(priv) > VER_1_X) {
+		/* This loop might need changes if enum regfield_ids is reordered */
+		for (j = CRITICAL_STATUS_0; j <= CRIT_THRESH_15; j += 16) {
+			for (i = 0; i < priv->feat->max_sensors; i++) {
+				int idx = j + i;
+
+				priv->rf[idx] = devm_regmap_field_alloc(dev, priv->tm_map,
+									priv->fields[idx]);
+				if (IS_ERR(priv->rf[idx])) {
+					ret = PTR_ERR(priv->rf[idx]);
+					goto err_put_device;
+				}
+			}
+		}
+	}
+
 	spin_lock_init(&priv->ul_lock);
 	tsens_enable_irq(priv);
 	tsens_debug_init(op);
diff --git a/drivers/thermal/qcom/tsens-v2.c b/drivers/thermal/qcom/tsens-v2.c
index a4d15e1abfdd..47d831df0803 100644
--- a/drivers/thermal/qcom/tsens-v2.c
+++ b/drivers/thermal/qcom/tsens-v2.c
@@ -51,8 +51,9 @@  static const struct reg_field tsens_v2_regfields[MAX_REGFIELDS] = {
 	[INT_EN]  = REG_FIELD(TM_INT_EN_OFF, 0, 2),
 
 	/* TEMPERATURE THRESHOLDS */
-	REG_FIELD_FOR_EACH_SENSOR16(LOW_THRESH, TM_Sn_UPPER_LOWER_THRESHOLD_OFF,  0,  11),
-	REG_FIELD_FOR_EACH_SENSOR16(UP_THRESH,  TM_Sn_UPPER_LOWER_THRESHOLD_OFF, 12,  23),
+	REG_FIELD_FOR_EACH_SENSOR16(LOW_THRESH,  TM_Sn_UPPER_LOWER_THRESHOLD_OFF,  0,  11),
+	REG_FIELD_FOR_EACH_SENSOR16(UP_THRESH,   TM_Sn_UPPER_LOWER_THRESHOLD_OFF, 12,  23),
+	REG_FIELD_FOR_EACH_SENSOR16(CRIT_THRESH, TM_Sn_CRITICAL_THRESHOLD_OFF,     0,  11),
 
 	/* INTERRUPTS [CLEAR/STATUS/MASK] */
 	REG_FIELD_SPLIT_BITS_0_15(LOW_INT_STATUS,  TM_UPPER_LOWER_INT_STATUS_OFF),
@@ -61,6 +62,9 @@  static const struct reg_field tsens_v2_regfields[MAX_REGFIELDS] = {
 	REG_FIELD_SPLIT_BITS_16_31(UP_INT_STATUS,  TM_UPPER_LOWER_INT_STATUS_OFF),
 	REG_FIELD_SPLIT_BITS_16_31(UP_INT_CLEAR,   TM_UPPER_LOWER_INT_CLEAR_OFF),
 	REG_FIELD_SPLIT_BITS_16_31(UP_INT_MASK,    TM_UPPER_LOWER_INT_MASK_OFF),
+	REG_FIELD_SPLIT_BITS_0_15(CRIT_INT_STATUS, TM_CRITICAL_INT_STATUS_OFF),
+	REG_FIELD_SPLIT_BITS_0_15(CRIT_INT_CLEAR,  TM_CRITICAL_INT_CLEAR_OFF),
+	REG_FIELD_SPLIT_BITS_0_15(CRIT_INT_MASK,   TM_CRITICAL_INT_MASK_OFF),
 
 	/* Sn_STATUS */
 	REG_FIELD_FOR_EACH_SENSOR16(LAST_TEMP,       TM_Sn_STATUS_OFF,  0,  11),
diff --git a/drivers/thermal/qcom/tsens.c b/drivers/thermal/qcom/tsens.c
index 7d317660211e..784c4976c4f9 100644
--- a/drivers/thermal/qcom/tsens.c
+++ b/drivers/thermal/qcom/tsens.c
@@ -121,6 +121,27 @@  static int tsens_register(struct tsens_priv *priv)
 
 	enable_irq_wake(irq);
 
+	if (tsens_version(priv) > VER_1_X) {
+		irq = platform_get_irq_byname(pdev, "critical");
+		if (irq < 0) {
+			ret = irq;
+			goto err_put_device;
+		}
+
+		ret = devm_request_threaded_irq(&pdev->dev, irq,
+						NULL, tsens_critical_irq_thread,
+						IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
+						dev_name(&pdev->dev), priv);
+		if (ret) {
+			dev_err(&pdev->dev, "%s: failed to get critical irq\n", __func__);
+			goto err_put_device;
+		}
+
+		enable_irq_wake(irq);
+	}
+
+	return 0;
+
 err_put_device:
 	put_device(&pdev->dev);
 	return ret;
diff --git a/drivers/thermal/qcom/tsens.h b/drivers/thermal/qcom/tsens.h
index 8b20f28c5c51..9b5a30533c52 100644
--- a/drivers/thermal/qcom/tsens.h
+++ b/drivers/thermal/qcom/tsens.h
@@ -23,6 +23,7 @@ 
 
 struct tsens_priv;
 
+/* IP version numbers in ascending order */
 enum tsens_ver {
 	VER_0_1 = 0,
 	VER_1_X,
@@ -32,6 +33,7 @@  enum tsens_ver {
 enum tsens_irq_type {
 	LOWER,
 	UPPER,
+	CRITICAL,
 };
 
 /**
@@ -374,6 +376,70 @@  enum regfield_ids {
 	CRITICAL_STATUS_13,
 	CRITICAL_STATUS_14,
 	CRITICAL_STATUS_15,
+	CRIT_INT_STATUS_0,	/* CRITICAL interrupt status */
+	CRIT_INT_STATUS_1,
+	CRIT_INT_STATUS_2,
+	CRIT_INT_STATUS_3,
+	CRIT_INT_STATUS_4,
+	CRIT_INT_STATUS_5,
+	CRIT_INT_STATUS_6,
+	CRIT_INT_STATUS_7,
+	CRIT_INT_STATUS_8,
+	CRIT_INT_STATUS_9,
+	CRIT_INT_STATUS_10,
+	CRIT_INT_STATUS_11,
+	CRIT_INT_STATUS_12,
+	CRIT_INT_STATUS_13,
+	CRIT_INT_STATUS_14,
+	CRIT_INT_STATUS_15,
+	CRIT_INT_CLEAR_0,	/* CRITICAL interrupt clear */
+	CRIT_INT_CLEAR_1,
+	CRIT_INT_CLEAR_2,
+	CRIT_INT_CLEAR_3,
+	CRIT_INT_CLEAR_4,
+	CRIT_INT_CLEAR_5,
+	CRIT_INT_CLEAR_6,
+	CRIT_INT_CLEAR_7,
+	CRIT_INT_CLEAR_8,
+	CRIT_INT_CLEAR_9,
+	CRIT_INT_CLEAR_10,
+	CRIT_INT_CLEAR_11,
+	CRIT_INT_CLEAR_12,
+	CRIT_INT_CLEAR_13,
+	CRIT_INT_CLEAR_14,
+	CRIT_INT_CLEAR_15,
+	CRIT_INT_MASK_0,	/* CRITICAL interrupt mask */
+	CRIT_INT_MASK_1,
+	CRIT_INT_MASK_2,
+	CRIT_INT_MASK_3,
+	CRIT_INT_MASK_4,
+	CRIT_INT_MASK_5,
+	CRIT_INT_MASK_6,
+	CRIT_INT_MASK_7,
+	CRIT_INT_MASK_8,
+	CRIT_INT_MASK_9,
+	CRIT_INT_MASK_10,
+	CRIT_INT_MASK_11,
+	CRIT_INT_MASK_12,
+	CRIT_INT_MASK_13,
+	CRIT_INT_MASK_14,
+	CRIT_INT_MASK_15,
+	CRIT_THRESH_0,		/* CRITICAL threshold values */
+	CRIT_THRESH_1,
+	CRIT_THRESH_2,
+	CRIT_THRESH_3,
+	CRIT_THRESH_4,
+	CRIT_THRESH_5,
+	CRIT_THRESH_6,
+	CRIT_THRESH_7,
+	CRIT_THRESH_8,
+	CRIT_THRESH_9,
+	CRIT_THRESH_10,
+	CRIT_THRESH_11,
+	CRIT_THRESH_12,
+	CRIT_THRESH_13,
+	CRIT_THRESH_14,
+	CRIT_THRESH_15,
 	MIN_STATUS_0,		/* MIN threshold violated */
 	MIN_STATUS_1,
 	MIN_STATUS_2,
@@ -460,6 +526,8 @@  struct tsens_context {
  * @srot_map: pointer to SROT register address space
  * @tm_offset: deal with old device trees that don't address TM and SROT
  *             address space separately
+ * @ul_lock: lock while processing upper/lower threshold interrupts
+ * @crit_lock: lock while processing critical threshold interrupts
  * @rf: array of regmap_fields used to store value of the field
  * @ctx: registers to be saved and restored during suspend/resume
  * @feat: features of the IP
@@ -479,6 +547,9 @@  struct tsens_priv {
 	/* lock for upper/lower threshold interrupts */
 	spinlock_t			ul_lock;
 
+	/* lock for critical threshold interrupts */
+	spinlock_t			crit_lock;
+
 	struct regmap_field		*rf[MAX_REGFIELDS];
 	struct tsens_context		ctx;
 	const struct tsens_features	*feat;
@@ -499,7 +570,9 @@  int get_temp_common(struct tsens_sensor *s, int *temp);
 int tsens_enable_irq(struct tsens_priv *priv);
 void tsens_disable_irq(struct tsens_priv *priv);
 int tsens_set_trips(void *_sensor, int low, int high);
+enum tsens_ver tsens_version(struct tsens_priv *priv);
 irqreturn_t tsens_irq_thread(int irq, void *data);
+irqreturn_t tsens_critical_irq_thread(int irq, void *data);
 
 /* TSENS target */
 extern const struct tsens_plat_data data_8960;