driver-api/serial/driver.rst

2 Low Level Serial API
10 The reference implementation is contained within amba-pl011.c.
14 Low Level Serial Hardware Driver
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17 The low level serial hardware driver is responsible for supplying port
19 by uart_ops) to the core serial driver.  The low level driver is also
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40 It is the responsibility of the low level hardware driver to perform the
41 necessary locking using port->lock.  There are some exceptions (which
44 There are two locks.  A per-port spinlock, and an overall semaphore.
46 From the core driver perspective, the port->lock locks the following
49 	port->mctrl
50 	port->icount
51 	port->state->xmit.head (circ_buf->head)
52 	port->state->xmit.tail (circ_buf->tail)
54 The low level driver is free to use this lock to provide any additional
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66 .. kernel-doc:: include/linux/serial_core.h
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72 .. kernel-doc:: drivers/tty/serial/serial_core.c
81 .. kernel-doc:: include/linux/serial_core.h
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88 allow low level drivers to register their own individual uart_port's with
99 ----------------------------
103 .. kernel-doc:: drivers/tty/serial/serial_mctrl_gpio.c