summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorAnsuel Smith <ansuelsmth@gmail.com>2021-10-07 19:28:59 +0200
committerDaniel Lezcano <daniel.lezcano@linaro.org>2021-10-16 20:24:43 +0200
commitd012f9189fda0f3a1b303780ba0bbc7298d0d349 (patch)
tree00fd50b0cff5cb15ff64552d31e276ff5243b0ff
parentthermal/drivers/qcom/lmh: make QCOM_LMH depends on QCOM_SCM (diff)
downloadlinux-d012f9189fda0f3a1b303780ba0bbc7298d0d349.tar.xz
linux-d012f9189fda0f3a1b303780ba0bbc7298d0d349.zip
thermal/drivers/tsens: Add timeout to get_temp_tsens_valid
The function can loop and lock the system if for whatever reason the bit for the target sensor is NEVER valid. This is the case if a sensor is disabled by the factory and the valid bit is never reported as actually valid. Add a timeout check and exit if a timeout occurs. As this is a very rare condition, handle the timeout only if the first read fails. While at it also rework the function to improve readability and convert to poll_timeout generic macro. Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Link: https://lore.kernel.org/r/20211007172859.583-1-ansuelsmth@gmail.com Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
-rw-r--r--drivers/thermal/qcom/tsens.c29
1 files changed, 14 insertions, 15 deletions
diff --git a/drivers/thermal/qcom/tsens.c b/drivers/thermal/qcom/tsens.c
index b1162e566a70..99a8d9f3e03c 100644
--- a/drivers/thermal/qcom/tsens.c
+++ b/drivers/thermal/qcom/tsens.c
@@ -603,22 +603,21 @@ int get_temp_tsens_valid(const struct tsens_sensor *s, int *temp)
int ret;
/* 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;
- }
- }
+ if (tsens_version(priv) == VER_0)
+ goto get_temp;
+
+ /* 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.
+ * Wait 1 us since it's the min of poll_timeout macro.
+ * Old value was 400 ns.
+ */
+ ret = regmap_field_read_poll_timeout(priv->rf[valid_idx], valid,
+ valid, 1, 20 * USEC_PER_MSEC);
+ if (ret)
+ return ret;
+get_temp:
/* Valid bit is set, OK to read the temperature */
*temp = tsens_hw_to_mC(s, temp_idx);