On 19/02/20 1:20 pm, Randy Dunlap wrote:
On 2/18/20 11:43 PM, Keerthy wrote:
The bandgap provides current and voltage reference for its internal
circuits and other analog IP blocks. The analog-to-digital
converter (ADC) produces an output value that is proportional
to the silicon temperature.
Currently reading temperatures and trend computing is supported
as there are no active/passive cooling agent supported.
Signed-off-by: Keerthy <j-keerthy@xxxxxx>
---
drivers/thermal/Kconfig | 12 ++
drivers/thermal/Makefile | 1 +
drivers/thermal/k3_bandgap.c | 342 +++++++++++++++++++++++++++++++++++
3 files changed, 355 insertions(+)
create mode 100644 drivers/thermal/k3_bandgap.c
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index 5a05db5438d6..fa598eddc7ac 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -251,6 +251,18 @@ config IMX_THERMAL
cpufreq is used as the cooling device to throttle CPUs when the
passive trip is crossed.
+config K3_THERMAL
+ bool "Texas Instruments K3 thermal support"
Hi,
Why is this bool and not tristate?
Definitely can work as tristate. I will fix it next version.
+ depends on THERMAL
+ depends on ARCH_K3 || COMPILE_TEST
+ help
+ If you say yes here you get thermal support for the Texas Instruments
+ K3 SoC family. The current chip supported is:
+ - AM654
+
+ This includes temperature reading functionality and also trend
+ computation.
+
config MAX77620_THERMAL
tristate "Temperature sensor driver for Maxim MAX77620 PMIC"
depends on MFD_MAX77620
diff --git a/drivers/thermal/k3_bandgap.c b/drivers/thermal/k3_bandgap.c
new file mode 100644
index 000000000000..35d904eb9857
--- /dev/null
+++ b/drivers/thermal/k3_bandgap.c
@@ -0,0 +1,342 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * TI Bandgap temperature sensor driver for K3 SoC Family
+ *
+ * Copyright (C) 2020 Texas Instruments Incorporated - http://www.ti.com/
+ */
+static int k3_bgp_read_temp(struct k3_thermal_data *devdata,
+ int *temp)
+{
+ struct k3_bandgap *bgp;
+ unsigned int dtemp, s0, s1, s2;
+
+ bgp = devdata->bgp;
+ /**
"/**" is used to indicate kernel-doc notation in the Linux kernel source files,
but this comment is not kernel-doc notation, so please just use "/*".
Okay
+ * Errata is applicable for am654 pg 1.0 silicon. There
+ * is a variation of the order for 8-10 degree centigrade.
+ * Work around that by getting the average of two closest
+ * readings out of three readings everytime we want to
+ * report temperatures.
+ *
+ * Errata workaround.
+ */
thanks.
Thanks for the review.
- Keerthy
