b12907f279
In U-boot, serial_tstc was use to determine is there have a character in serial console that pending for read. If there is no "pending" function implemented in serial driver, the serial-uclass will return "true(1)" to indicate there have a character pending to read. Thus, read a character from nulldev serial will result in continuous getting -EAGAIN return which might lead system to hang. This commit is to fix a bug in nulldev serial which implement "pending" function in nulldev serial to always indicate there is no character in console that pending for read. Signed-off-by: Wilson Lee <wilson.lee@ni.com> Cc: Joe Hershberger <joe.hershberger@ni.com> Cc: Keng Soon Cheah <keng.soon.cheah@ni.com> Cc: Chen Yee Chew <chen.yee.chew@ni.com> Cc: Bin Meng <bmeng.cn@gmail.com>
55 lines
976 B
C
55 lines
976 B
C
/*
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* Copyright (c) 2015 National Instruments
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*
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* SPDX-License-Identifier: GPL-2.0+
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*/
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#include <common.h>
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#include <dm.h>
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#include <serial.h>
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static int nulldev_serial_setbrg(struct udevice *dev, int baudrate)
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{
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return 0;
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}
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static int nulldev_serial_getc(struct udevice *dev)
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{
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return -EAGAIN;
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}
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static int nulldev_serial_pending(struct udevice *dev, bool input)
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{
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return 0;
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}
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static int nulldev_serial_input(struct udevice *dev)
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{
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return 0;
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}
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static int nulldev_serial_putc(struct udevice *dev, const char ch)
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{
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return 0;
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}
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static const struct udevice_id nulldev_serial_ids[] = {
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{ .compatible = "nulldev-serial" },
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{ }
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};
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const struct dm_serial_ops nulldev_serial_ops = {
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.putc = nulldev_serial_putc,
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.pending = nulldev_serial_pending,
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.getc = nulldev_serial_getc,
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.setbrg = nulldev_serial_setbrg,
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};
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U_BOOT_DRIVER(serial_nulldev) = {
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.name = "serial_nulldev",
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.id = UCLASS_SERIAL,
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.of_match = nulldev_serial_ids,
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.ops = &nulldev_serial_ops,
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};
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