target/linux/mediatek/patches-6.6/830-v6.4-33-thermal-drivers-mediatek-lvts_thermal-Don-t-leave-th.patch

   1 From bd1ccf9408e6155564530af5e09b53ae497fe332 Mon Sep 17 00:00:00 2001
   2 From: =?UTF-8?q?N=C3=ADcolas=20F=2E=20R=2E=20A=2E=20Prado?=
   3  <nfraprado@collabora.com>
   4 Date: Thu, 6 Jul 2023 11:37:36 -0400
   5 Subject: [PATCH 29/42] thermal/drivers/mediatek/lvts_thermal: Don't leave
   6  threshold zeroed
   7 MIME-Version: 1.0
   8 Content-Type: text/plain; charset=UTF-8
   9 Content-Transfer-Encoding: 8bit
  10
  11 The thermal framework might leave the low threshold unset if there
  12 aren't any lower trip points. This leaves the register zeroed, which
  13 translates to a very high temperature for the low threshold. The
  14 interrupt for this threshold is then immediately triggered, and the
  15 state machine gets stuck, preventing any other temperature monitoring
  16 interrupts to ever trigger.
  17
  18 (The same happens by not setting the Cold or Hot to Normal thresholds
  19 when using those)
  20
  21 Set the unused threshold to a valid low value. This value was chosen so
  22 that for any valid golden temperature read from the efuse, when the
  23 value is converted to raw and back again to milliCelsius, the result
  24 doesn't underflow.
  25
  26 Fixes: f5f633b18234 ("thermal/drivers/mediatek: Add the Low Voltage Thermal Sensor driver")
  27 Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
  28 Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
  29 Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
  30 Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
  31 Link: https://lore.kernel.org/r/20230706153823.201943-6-nfraprado@collabora.com
  32 ---
  33  drivers/thermal/mediatek/lvts_thermal.c | 12 ++++++------
  34  1 file changed, 6 insertions(+), 6 deletions(-)
  35
  36 --- a/drivers/thermal/mediatek/lvts_thermal.c
  37 +++ b/drivers/thermal/mediatek/lvts_thermal.c
  38 @@ -83,6 +83,8 @@
  39
  40  #define LVTS_HW_SHUTDOWN_MT8195                105000
  41
  42 +#define LVTS_MINIMUM_THRESHOLD         20000
  43 +
  44  static int golden_temp = LVTS_GOLDEN_TEMP_DEFAULT;
  45  static int coeff_b = LVTS_COEFF_B;
  46
  47 @@ -294,7 +296,7 @@ static int lvts_set_trips(struct thermal
  48  {
  49         struct lvts_sensor *lvts_sensor = thermal_zone_device_priv(tz);
  50         void __iomem *base = lvts_sensor->base;
  51 -       u32 raw_low = lvts_temp_to_raw(low);
  52 +       u32 raw_low = lvts_temp_to_raw(low != -INT_MAX ? low : LVTS_MINIMUM_THRESHOLD);
  53         u32 raw_high = lvts_temp_to_raw(high);
  54
  55         /*
  56 @@ -306,11 +308,9 @@ static int lvts_set_trips(struct thermal
  57          *
  58          * 14-0 : Raw temperature for threshold
  59          */
  60 -       if (low != -INT_MAX) {
  61 -               pr_debug("%s: Setting low limit temperature interrupt: %d\n",
  62 -                        thermal_zone_device_type(tz), low);
  63 -               writel(raw_low, LVTS_OFFSETL(base));
  64 -       }
  65 +       pr_debug("%s: Setting low limit temperature interrupt: %d\n",
  66 +                thermal_zone_device_type(tz), low);
  67 +       writel(raw_low, LVTS_OFFSETL(base));
  68
  69         /*
  70          * High offset temperature threshold