thermal: imx_thermal: fix busywait if IMX6 temp <0C

The temperature calculation must be typecasted to keep the compiler
from sign extending a negative value prior to division.

This fixes an issue where if the CPU temperature is <0C it will get stuck
in the busywait loop until the CPU heats up to 0C.

Cc: Ye Li <b37916@freescale.com>
Cc: Jason Liu <r64343@freescale.com>
Signed-off-by: Tim Harvey <tharvey@gateworks.com>

diff --git a/drivers/thermal/imx_thermal.c b/drivers/thermal/imx_thermal.c
index 42ca8d0b6b3de9ac51d7f33689c91a283857e844..3c6c9679f97a89b30a30caf8b8bafb9238a41213 100644 (file)
--- a/drivers/thermal/imx_thermal.c
+++ b/drivers/thermal/imx_thermal.c
@@ -115,7 +115,7 @@ static int read_cpu_temperature(struct udevice *dev)
        writel(TEMPSENSE0_FINISHED, &anatop->tempsense0_clr);
 
        /* milli_Tmeas = c2 - Nmeas * c1 */
-       temperature = (c2 - n_meas * c1)/1000;
+       temperature = (long)(c2 - n_meas * c1)/1000;
 
        /* power down anatop thermal sensor */
        writel(TEMPSENSE0_POWER_DOWN, &anatop->tempsense0_set);