4.9-stable review patch. If anyone has any objections, please let me know.
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From: Matt Ranostay matt.ranostay@konsulko.com
[ Upstream commit ce054546cc2c26891cefa2f284d90d93b52205de ]
ADC channel 0 photodiode detects both infrared + visible light, but ADC channel 1 just detects infrared. However, the latter is a bit more sensitive in that range so complete darkness or low light causes a error condition in which the chan0 - chan1 is negative that results in a -EAGAIN.
This patch changes the resulting lux1_input sysfs attribute message from "Resource temporarily unavailable" to a user-grokable lux value of 0.
Cc: Arnd Bergmann arnd@arndb.de Cc: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Matt Ranostay matt.ranostay@konsulko.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/misc/tsl2550.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/misc/tsl2550.c +++ b/drivers/misc/tsl2550.c @@ -177,7 +177,7 @@ static int tsl2550_calculate_lux(u8 ch0, } else lux = 0; else - return -EAGAIN; + return 0;
/* LUX range check */ return lux > TSL2550_MAX_LUX ? TSL2550_MAX_LUX : lux;