• Nishanth Menon's avatar
    hwmon: (gpio-fan) Remove un-necessary speed_index lookup for thermal hook · 000e0949
    Nishanth Menon authored
    Thermal hook gpio_fan_get_cur_state is only interested in knowing
    the current speed index that was setup in the system, this is
    already available as part of fan_data->speed_index which is always
    set by set_fan_speed. Using get_fan_speed_index is useful when we
    have no idea about the fan speed configuration (for example during
    fan_ctrl_init).
    
    When thermal framework invokes
    gpio_fan_get_cur_state=>get_fan_speed_index via gpio_fan_get_cur_state
    especially in a polled configuration for thermal governor, we
    basically hog the i2c interface to the extent that other functions
    fail to get any traffic out :(.
    
    Instead, just provide the last state set in the driver - since the gpio
    fan driver is responsible for the fan state immaterial of override, the
    fan_data->speed_index should accurately reflect the state.
    
    Fixes: b5cf88e4 ("(gpio-fan): Add thermal control hooks")
    Reported-by: default avatarTony Lindgren <tony@atomide.com>
    Cc: Guenter Roeck <linux@roeck-us.net>
    Cc: Eduardo Valentin <edubezval@gmail.com>
    Signed-off-by: default avatarNishanth Menon <nm@ti.com>
    Cc: stable@vger.kernel.org
    Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
    000e0949
gpio-fan.c 16 KB