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From:   Amit Kucheria <amit.kucheria@linaro.org>
Date:   Mon, 23 Nov 2020 01:35:22 +0530
Message-ID: <CAHLCerMArOceCFQ1XFbsZCAnUdKVX3TVnAb502w+kxmO97bdJg@mail.gmail.com>
Subject: Re: [RFC PATCH v6 2/8] drivers: thermal: tsens: Add VER_0 tsens version
To:     Ansuel Smith <ansuelsmth@gmail.com>
Cc:     Andy Gross <agross@kernel.org>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        Zhang Rui <rui.zhang@intel.com>,
        Daniel Lezcano <daniel.lezcano@linaro.org>,
        Rob Herring <robh+dt@kernel.org>,
        linux-arm-msm <linux-arm-msm@vger.kernel.org>,
        Linux PM list <linux-pm@vger.kernel.org>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>, LKML <linux-kernel@vger.kernel.org>
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Precedence: bulk

Hi Ansuel,

See comments inline.

On Fri, Aug 14, 2020 at 7:12 PM Ansuel Smith <ansuelsmth@gmail.com> wrote:
>
> VER_0 is used to describe device based on tsens version before v0.1.
> These device are devices based on msm8960 for example apq8064 or
> ipq806x.
>
> Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
> ---
>  drivers/thermal/qcom/tsens.c | 122 +++++++++++++++++++++++++++++++----
>  drivers/thermal/qcom/tsens.h |   7 +-
>  2 files changed, 114 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/thermal/qcom/tsens.c b/drivers/thermal/qcom/tsens.c
> index 9fe9a2b26705..965c4799918a 100644
> --- a/drivers/thermal/qcom/tsens.c
> +++ b/drivers/thermal/qcom/tsens.c
> @@ -516,6 +516,15 @@ static irqreturn_t tsens_irq_thread(int irq, void *data)
>                         dev_dbg(priv->dev, "[%u] %s: no violation:  %d\n",
>                                 hw_id, __func__, temp);
>                 }
> +
> +               if (tsens_version(priv) < VER_0_1) {
> +                       /* Constraint: There is only 1 interrupt control register for all
> +                        * 11 temperature sensor. So monitoring more than 1 sensor based
> +                        * on interrupts will yield inconsistent result. To overcome this
> +                        * issue we will monitor only sensor 0 which is the master sensor.
> +                        */
> +                       break;
> +               }
>         }
>
>         return IRQ_HANDLED;
> @@ -531,6 +540,13 @@ static int tsens_set_trips(void *_sensor, int low, int high)
>         int high_val, low_val, cl_high, cl_low;
>         u32 hw_id = s->hw_id;
>
> +       if (tsens_version(priv) < VER_0_1) {
> +               /* Pre v0.1 IP had a single register for each type of interrupt
> +                * and thresholds
> +                */
> +               hw_id = 0;
> +       }
> +
>         dev_dbg(dev, "[%u] %s: proposed thresholds: (%d:%d)\n",
>                 hw_id, __func__, low, high);
>
> @@ -584,18 +600,21 @@ int get_temp_tsens_valid(const struct tsens_sensor *s, int *temp)
>         u32 valid;
>         int ret;
>
> -       ret = regmap_field_read(priv->rf[valid_idx], &valid);
> -       if (ret)
> -               return ret;
> -       while (!valid) {
> -               /* Valid bit is 0 for 6 AHB clock cycles.
> -                * At 19.2MHz, 1 AHB clock is ~60ns.
> -                * We should enter this loop very, very rarely.
> -                */
> -               ndelay(400);
> +       /* VER_0 doesn't have VALID bit */
> +       if (tsens_version(priv) >= VER_0_1) {
>                 ret = regmap_field_read(priv->rf[valid_idx], &valid);
>                 if (ret)
>                         return ret;
> +               while (!valid) {
> +                       /* Valid bit is 0 for 6 AHB clock cycles.
> +                        * At 19.2MHz, 1 AHB clock is ~60ns.
> +                        * We should enter this loop very, very rarely.
> +                        */
> +                       ndelay(400);
> +                       ret = regmap_field_read(priv->rf[valid_idx], &valid);
> +                       if (ret)
> +                               return ret;
> +               }

Let's revisit this after fixing patch 1.


>         }
>
>         /* Valid bit is set, OK to read the temperature */
> @@ -763,6 +782,10 @@ int __init init_common(struct tsens_priv *priv)
>                 goto err_put_device;
>         }
>
> +       /* VER_0 have only tm_map */
> +       if (!priv->srot_map)
> +               priv->srot_map = priv->tm_map;
> +
>         if (tsens_version(priv) > VER_0_1) {
>                 for (i = VER_MAJOR; i <= VER_STEP; i++) {
>                         priv->rf[i] = devm_regmap_field_alloc(dev, priv->srot_map,
> @@ -781,6 +804,10 @@ int __init init_common(struct tsens_priv *priv)
>                 ret = PTR_ERR(priv->rf[TSENS_EN]);
>                 goto err_put_device;
>         }
> +       /* in VER_0 TSENS need to be explicitly enabled */
> +       if (tsens_version(priv) == VER_0)
> +               regmap_field_write(priv->rf[TSENS_EN], 1);
> +
>         ret = regmap_field_read(priv->rf[TSENS_EN], &enabled);
>         if (ret)
>                 goto err_put_device;
> @@ -803,6 +830,61 @@ int __init init_common(struct tsens_priv *priv)
>                 goto err_put_device;
>         }
>
> +       priv->rf[TSENS_EN] = devm_regmap_field_alloc(dev, priv->tm_map,
> +                                                    priv->fields[TSENS_EN]);
> +       if (IS_ERR(priv->rf[TSENS_EN])) {
> +               ret = PTR_ERR(priv->rf[TSENS_EN]);
> +               goto err_put_device;
> +       }
> +
> +       priv->rf[TSENS_SW_RST] = devm_regmap_field_alloc(
> +               dev, priv->tm_map, priv->fields[TSENS_EN]);
> +       if (IS_ERR(priv->rf[TSENS_EN])) {
> +               ret = PTR_ERR(priv->rf[TSENS_EN]);
> +               goto err_put_device;
> +       }
> +
> +       priv->rf[LOW_INT_CLEAR_0] = devm_regmap_field_alloc(
> +               dev, priv->tm_map, priv->fields[LOW_INT_CLEAR_0]);
> +       if (IS_ERR(priv->rf[LOW_INT_CLEAR_0])) {
> +               ret = PTR_ERR(priv->rf[LOW_INT_CLEAR_0]);
> +               goto err_put_device;
> +       }
> +
> +       priv->rf[UP_INT_CLEAR_0] = devm_regmap_field_alloc(
> +               dev, priv->tm_map, priv->fields[UP_INT_CLEAR_0]);
> +       if (IS_ERR(priv->rf[UP_INT_CLEAR_0])) {
> +               ret = PTR_ERR(priv->rf[UP_INT_CLEAR_0]);
> +               goto err_put_device;
> +       }
> +
> +       /* VER_0 require to set MIN and MAX THRESH */
> +       if (tsens_version(priv) < VER_0_1) {
> +               priv->rf[MIN_THRESH_0] = devm_regmap_field_alloc(
> +                       dev, priv->tm_map, priv->fields[MIN_THRESH_0]);
> +               if (IS_ERR(priv->rf[MIN_THRESH_0])) {
> +                       ret = PTR_ERR(priv->rf[MIN_THRESH_0]);
> +                       goto err_put_device;
> +               }
> +
> +               priv->rf[MAX_THRESH_0] = devm_regmap_field_alloc(
> +                       dev, priv->tm_map, priv->fields[MAX_THRESH_0]);
> +               if (IS_ERR(priv->rf[MAX_THRESH_0])) {
> +                       ret = PTR_ERR(priv->rf[MAX_THRESH_0]);
> +                       goto err_put_device;
> +               }
> +
> +               regmap_field_write(priv->rf[MIN_THRESH_0], 0);
> +               regmap_field_write(priv->rf[MAX_THRESH_0], 120000);
> +       }
> +
> +       priv->rf[TRDY] =
> +               devm_regmap_field_alloc(dev, priv->tm_map, priv->fields[TRDY]);
> +       if (IS_ERR(priv->rf[TRDY])) {
> +               ret = PTR_ERR(priv->rf[TRDY]);
> +               goto err_put_device;
> +       }
> +
>         /* This loop might need changes if enum regfield_ids is reordered */
>         for (j = LAST_TEMP_0; j <= UP_THRESH_15; j += 16) {
>                 for (i = 0; i < priv->feat->max_sensors; i++) {
> @@ -856,7 +938,11 @@ int __init init_common(struct tsens_priv *priv)
>         }
>
>         spin_lock_init(&priv->ul_lock);
> -       tsens_enable_irq(priv);
> +
> +       /* VER_0 interrupt doesn't need to be enabled */
> +       if (tsens_version(priv) >= VER_0_1)
> +               tsens_enable_irq(priv);
> +
>         tsens_debug_init(op);
>
>  err_put_device:
> @@ -952,10 +1038,18 @@ static int tsens_register_irq(struct tsens_priv *priv, char *irqname,
>                 if (irq == -ENXIO)
>                         ret = 0;
>         } else {
> -               ret = devm_request_threaded_irq(&pdev->dev, irq,
> -                                               NULL, thread_fn,
> -                                               IRQF_ONESHOT,
> -                                               dev_name(&pdev->dev), priv);
> +               /* VER_0 interrupt is TRIGGER_RISING, VER_0_1 and up is ONESHOT */
> +               if (tsens_version(priv) > VER_0)
> +                       ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
> +                                                       thread_fn, IRQF_ONESHOT,
> +                                                       dev_name(&pdev->dev),
> +                                                       priv);
> +               else
> +                       ret = devm_request_threaded_irq(&pdev->dev, irq,
> +                                                       thread_fn, NULL,
> +                                                       IRQF_TRIGGER_RISING,
> +                                                       dev_name(&pdev->dev),
> +                                                       priv);


Just set a flag variable to ONESHOT OR TRIGGER_RISING and use that in the call.

>                 if (ret)
>                         dev_err(&pdev->dev, "%s: failed to get irq\n",
>                                 __func__);
> diff --git a/drivers/thermal/qcom/tsens.h b/drivers/thermal/qcom/tsens.h
> index 59d01162c66a..f1120791737c 100644
> --- a/drivers/thermal/qcom/tsens.h
> +++ b/drivers/thermal/qcom/tsens.h
> @@ -25,7 +25,8 @@ struct tsens_priv;
>
>  /* IP version numbers in ascending order */
>  enum tsens_ver {
> -       VER_0_1 = 0,
> +       VER_0 = 0,
> +       VER_0_1,
>         VER_1_X,
>         VER_2_X,
>  };
> @@ -441,6 +442,10 @@ enum regfield_ids {
>         CRIT_THRESH_14,
>         CRIT_THRESH_15,
>
> +       /* VER_0 MIN MAX THRESH */
> +       MIN_THRESH_0,
> +       MAX_THRESH_0,
> +

Consider reusing LOW_THRESH_0 and UP_THRESH_0 for these?

>         /* WATCHDOG */
>         WDOG_BARK_STATUS,
>         WDOG_BARK_CLEAR,
> --
> 2.27.0
>