| Parallel Port Devices |
| ===================== |
| |
| .. kernel-doc:: include/linux/parport.h |
| :internal: |
| |
| .. kernel-doc:: drivers/parport/ieee1284.c |
| :export: |
| |
| .. kernel-doc:: drivers/parport/share.c |
| :export: |
| |
| .. kernel-doc:: drivers/parport/daisy.c |
| :internal: |
| |
| 16x50 UART Driver |
| ================= |
| |
| .. kernel-doc:: drivers/tty/serial/8250/8250_core.c |
| :export: |
| |
| See serial/driver.rst for related APIs. |
| |
| Pulse-Width Modulation (PWM) |
| ============================ |
| |
| Pulse-width modulation is a modulation technique primarily used to |
| control power supplied to electrical devices. |
| |
| The PWM framework provides an abstraction for providers and consumers of |
| PWM signals. A controller that provides one or more PWM signals is |
| registered as :c:type:`struct pwm_chip <pwm_chip>`. Providers |
| are expected to embed this structure in a driver-specific structure. |
| This structure contains fields that describe a particular chip. |
| |
| A chip exposes one or more PWM signal sources, each of which exposed as |
| a :c:type:`struct pwm_device <pwm_device>`. Operations can be |
| performed on PWM devices to control the period, duty cycle, polarity and |
| active state of the signal. |
| |
| Note that PWM devices are exclusive resources: they can always only be |
| used by one consumer at a time. |
| |
| .. kernel-doc:: include/linux/pwm.h |
| :internal: |
| |
| .. kernel-doc:: drivers/pwm/core.c |
| :export: |
