• H Hartley Sweeten's avatar
    pwm: Add sysfs interface · 76abbdde
    H Hartley Sweeten authored
    Add a simple sysfs interface to the generic PWM framework.
    
      /sys/class/pwm/
      `-- pwmchipN/           for each PWM chip
          |-- export          (w/o) ask the kernel to export a PWM channel
          |-- npwm            (r/o) number of PWM channels in this PWM chip
          |-- pwmX/           for each exported PWM channel
          |   |-- duty_cycle  (r/w) duty cycle (in nanoseconds)
          |   |-- enable      (r/w) enable/disable PWM
          |   |-- period      (r/w) period (in nanoseconds)
          |   `-- polarity    (r/w) polarity of PWM (normal/inversed)
          `-- unexport        (w/o) return a PWM channel to the kernel
    
    Based on work by Lars Poeschel.
    Signed-off-by: default avatarH Hartley Sweeten <hsweeten@visionengravers.com>
    Cc: Thierry Reding <thierry.reding@gmail.com>
    Cc: Lars Poeschel <poeschel@lemonage.de>
    Cc: Ryan Mallon <rmallon@gmail.com>
    Cc: Rob Landley <rob@landley.net>
    Signed-off-by: default avatarThierry Reding <thierry.reding@gmail.com>
    76abbdde
sysfs.c 7.8 KB