Commit b98467fe authored Oct 29, 2020 by Peter Ujfalusi Committed by Daniel Lezcano Nov 12, 2020

thermal: ti-soc-thermal: Disable the CPU PM notifier for OMAP4430



It has been observed that on OMAP4430 (ES2.0, ES2.1 and ES2.3) the enabled
notifier causes errors on the DTEMP readout values:

ti-soc-thermal 4a002260.bandgap: in range ADC val: 52
ti-soc-thermal 4a002260.bandgap: in range ADC val: 64
ti-soc-thermal 4a002260.bandgap: in range ADC val: 64
ti-soc-thermal 4a002260.bandgap: out of range ADC val: 0
thermal thermal_zone0: failed to read out thermal zone (-5)
ti-soc-thermal 4a002260.bandgap: out of range ADC val: 0
thermal thermal_zone0: failed to read out thermal zone (-5)
ti-soc-thermal 4a002260.bandgap: out of range ADC val: 4
thermal thermal_zone0: failed to read out thermal zone (-5)
ti-soc-thermal 4a002260.bandgap: in range ADC val: 100

raw 100 translates to 133 Celsius on omap4-sdp, triggering shutdown due to
critical temperature.

When the notifier is disable for OMAP4430 the DTEMP values are stable:
ti-soc-thermal 4a002260.bandgap: in range ADC val: 56
ti-soc-thermal 4a002260.bandgap: in range ADC val: 56
ti-soc-thermal 4a002260.bandgap: in range ADC val: 57
ti-soc-thermal 4a002260.bandgap: in range ADC val: 57
ti-soc-thermal 4a002260.bandgap: in range ADC val: 56

Fixes: 5093402e ("thermal: ti-soc-thermal: Enable addition power management")
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Acked-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20201029100335.27665-1-peter.ujfalusi@ti.com

parent f8394f23

drivers/thermal/ti-soc-thermal/ti-bandgap.c

+16 −2

Original line number	Diff line number	Diff line
		@@ -20,6 +20,7 @@
		#include <linux/err.h>
		#include <linux/types.h>
		#include <linux/spinlock.h>
		#include <linux/sys_soc.h>
		#include <linux/reboot.h>
		#include <linux/of_device.h>
		#include <linux/of_platform.h>
		@@ -864,6 +865,17 @@ static struct ti_bandgap ti_bandgap_build(struct platform_device pdev)
		return bgp;
		}

		/*
		* List of SoCs on which the CPU PM notifier can cause erros on the DTEMP
		* readout.
		* Enabled notifier on these machines results in erroneous, random values which
		* could trigger unexpected thermal shutdown.
		*/
		static const struct soc_device_attribute soc_no_cpu_notifier[] = {
		{ .machine = "OMAP4430" },
		{ /* sentinel */ },
		};

		/* Device driver call backs */

		static
		@@ -1020,6 +1032,7 @@ int ti_bandgap_probe(struct platform_device *pdev)

		#ifdef CONFIG_PM_SLEEP
		bgp->nb.notifier_call = bandgap_omap_cpu_notifier;
		if (!soc_device_match(soc_no_cpu_notifier))
		cpu_pm_register_notifier(&bgp->nb);
		#endif

		@@ -1056,6 +1069,7 @@ int ti_bandgap_remove(struct platform_device *pdev)
		struct ti_bandgap *bgp = platform_get_drvdata(pdev);
		int i;

		if (!soc_device_match(soc_no_cpu_notifier))
		cpu_pm_unregister_notifier(&bgp->nb);

		/* Remove sensor interfaces */

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