u-boot/drivers/serial/serial-uclass.c
Michal Suchanek c726fc01cf dm: treewide: Use uclass_first_device_err when accessing one device
There is a number of users that use uclass_first_device to access the
first and (assumed) only device in uclass.

Some check the return value of uclass_first_device and also that a
device was returned which is exactly what uclass_first_device_err does.

Some are not checking that a device was returned and can potentially
crash if no device exists in the uclass. Finally there is one that
returns NULL on error either way.

Convert all of these to use uclass_first_device_err instead, the return
value will be removed from uclass_first_device in a later patch.

Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
2022-10-17 21:17:12 -06:00

587 lines
12 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2014 The Chromium OS Authors.
*/
#define LOG_CATEGORY UCLASS_SERIAL
#include <common.h>
#include <dm.h>
#include <env_internal.h>
#include <errno.h>
#include <malloc.h>
#include <os.h>
#include <serial.h>
#include <stdio_dev.h>
#include <watchdog.h>
#include <asm/global_data.h>
#include <dm/lists.h>
#include <dm/device-internal.h>
#include <dm/of_access.h>
#include <linux/delay.h>
DECLARE_GLOBAL_DATA_PTR;
/*
* Table with supported baudrates (defined in config_xyz.h)
*/
static const unsigned long baudrate_table[] = CONFIG_SYS_BAUDRATE_TABLE;
#if CONFIG_IS_ENABLED(SERIAL_PRESENT)
static int serial_check_stdout(const void *blob, struct udevice **devp)
{
int node = -1;
const char *str, *p, *name;
int namelen;
/* Check for a chosen console */
str = fdtdec_get_chosen_prop(blob, "stdout-path");
if (str) {
p = strchr(str, ':');
namelen = p ? p - str : strlen(str);
node = fdt_path_offset_namelen(blob, str, namelen);
if (node < 0) {
/*
* Deal with things like
* stdout-path = "serial0:115200n8";
*
* We need to look up the alias and then follow it to
* the correct node.
*/
name = fdt_get_alias_namelen(blob, str, namelen);
if (name)
node = fdt_path_offset(blob, name);
}
}
if (node < 0)
node = fdt_path_offset(blob, "console");
if (!uclass_get_device_by_of_offset(UCLASS_SERIAL, node, devp))
return 0;
/*
* If the console is not marked to be bound before relocation, bind it
* anyway.
*/
if (node > 0 && !lists_bind_fdt(gd->dm_root, offset_to_ofnode(node),
devp, NULL, false)) {
if (device_get_uclass_id(*devp) == UCLASS_SERIAL &&
!device_probe(*devp))
return 0;
}
return -ENODEV;
}
static void serial_find_console_or_panic(void)
{
const void *blob = gd->fdt_blob;
struct udevice *dev;
#ifdef CONFIG_SERIAL_SEARCH_ALL
int ret;
#endif
if (CONFIG_IS_ENABLED(OF_PLATDATA)) {
uclass_first_device(UCLASS_SERIAL, &dev);
if (dev) {
gd->cur_serial_dev = dev;
return;
}
} else if (CONFIG_IS_ENABLED(OF_CONTROL) && blob) {
/* Live tree has support for stdout */
if (of_live_active()) {
struct device_node *np = of_get_stdout();
if (np && !uclass_get_device_by_ofnode(UCLASS_SERIAL,
np_to_ofnode(np), &dev)) {
gd->cur_serial_dev = dev;
return;
}
} else {
if (!serial_check_stdout(blob, &dev)) {
gd->cur_serial_dev = dev;
return;
}
}
}
if (!IS_ENABLED(CONFIG_SPL_BUILD) || !CONFIG_IS_ENABLED(OF_CONTROL) ||
!blob) {
/*
* Try to use CONFIG_CONS_INDEX if available (it is numbered
* from 1!).
*
* Failing that, get the device with sequence number 0, or in
* extremis just the first working serial device we can find.
* But we insist on having a console (even if it is silent).
*/
#ifdef CONFIG_CONS_INDEX
#define INDEX (CONFIG_CONS_INDEX - 1)
#else
#define INDEX 0
#endif
#ifdef CONFIG_SERIAL_SEARCH_ALL
if (!uclass_get_device_by_seq(UCLASS_SERIAL, INDEX, &dev) ||
!uclass_get_device(UCLASS_SERIAL, INDEX, &dev)) {
if (dev_get_flags(dev) & DM_FLAG_ACTIVATED) {
gd->cur_serial_dev = dev;
return;
}
}
/* Search for any working device */
for (ret = uclass_first_device_check(UCLASS_SERIAL, &dev);
dev;
ret = uclass_next_device_check(&dev)) {
if (!ret) {
/* Device did succeed probing */
gd->cur_serial_dev = dev;
return;
}
}
#else
if (!uclass_get_device_by_seq(UCLASS_SERIAL, INDEX, &dev) ||
!uclass_get_device(UCLASS_SERIAL, INDEX, &dev) ||
!uclass_first_device_err(UCLASS_SERIAL, &dev)) {
gd->cur_serial_dev = dev;
return;
}
#endif
#undef INDEX
}
#ifdef CONFIG_REQUIRE_SERIAL_CONSOLE
panic_str("No serial driver found");
#endif
}
#endif /* CONFIG_SERIAL_PRESENT */
/* Called prior to relocation */
int serial_init(void)
{
#if CONFIG_IS_ENABLED(SERIAL_PRESENT)
serial_find_console_or_panic();
gd->flags |= GD_FLG_SERIAL_READY;
serial_setbrg();
#endif
return 0;
}
/* Called after relocation */
int serial_initialize(void)
{
/* Scanning uclass to probe devices */
if (IS_ENABLED(CONFIG_SERIAL_PROBE_ALL)) {
int ret;
ret = uclass_probe_all(UCLASS_SERIAL);
if (ret)
return ret;
}
return serial_init();
}
static void _serial_putc(struct udevice *dev, char ch)
{
struct dm_serial_ops *ops = serial_get_ops(dev);
int err;
if (ch == '\n')
_serial_putc(dev, '\r');
do {
err = ops->putc(dev, ch);
} while (err == -EAGAIN);
}
static int __serial_puts(struct udevice *dev, const char *str, size_t len)
{
struct dm_serial_ops *ops = serial_get_ops(dev);
do {
ssize_t written = ops->puts(dev, str, len);
if (written < 0)
return written;
str += written;
len -= written;
} while (len);
return 0;
}
static void _serial_puts(struct udevice *dev, const char *str)
{
struct dm_serial_ops *ops = serial_get_ops(dev);
if (!CONFIG_IS_ENABLED(SERIAL_PUTS) || !ops->puts) {
while (*str)
_serial_putc(dev, *str++);
return;
}
do {
const char *newline = strchrnul(str, '\n');
size_t len = newline - str;
if (__serial_puts(dev, str, len))
return;
if (*newline && __serial_puts(dev, "\r\n", 2))
return;
str += len + !!*newline;
} while (*str);
}
#ifdef CONFIG_CONSOLE_FLUSH_SUPPORT
static void _serial_flush(struct udevice *dev)
{
struct dm_serial_ops *ops = serial_get_ops(dev);
if (!ops->pending)
return;
while (ops->pending(dev, false) > 0)
;
}
#endif
static int __serial_getc(struct udevice *dev)
{
struct dm_serial_ops *ops = serial_get_ops(dev);
int err;
do {
err = ops->getc(dev);
if (err == -EAGAIN)
schedule();
} while (err == -EAGAIN);
return err >= 0 ? err : 0;
}
static int __serial_tstc(struct udevice *dev)
{
struct dm_serial_ops *ops = serial_get_ops(dev);
if (ops->pending)
return ops->pending(dev, true);
return 1;
}
#if CONFIG_IS_ENABLED(SERIAL_RX_BUFFER)
static int _serial_tstc(struct udevice *dev)
{
struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
/* Read all available chars into the RX buffer */
while (__serial_tstc(dev)) {
upriv->buf[upriv->wr_ptr++] = __serial_getc(dev);
upriv->wr_ptr %= CONFIG_SERIAL_RX_BUFFER_SIZE;
}
return upriv->rd_ptr != upriv->wr_ptr ? 1 : 0;
}
static int _serial_getc(struct udevice *dev)
{
struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
char val;
if (upriv->rd_ptr == upriv->wr_ptr)
return __serial_getc(dev);
val = upriv->buf[upriv->rd_ptr++];
upriv->rd_ptr %= CONFIG_SERIAL_RX_BUFFER_SIZE;
return val;
}
#else /* CONFIG_IS_ENABLED(SERIAL_RX_BUFFER) */
static int _serial_getc(struct udevice *dev)
{
return __serial_getc(dev);
}
static int _serial_tstc(struct udevice *dev)
{
return __serial_tstc(dev);
}
#endif /* CONFIG_IS_ENABLED(SERIAL_RX_BUFFER) */
void serial_putc(char ch)
{
if (gd->cur_serial_dev)
_serial_putc(gd->cur_serial_dev, ch);
}
void serial_puts(const char *str)
{
if (gd->cur_serial_dev)
_serial_puts(gd->cur_serial_dev, str);
}
#ifdef CONFIG_CONSOLE_FLUSH_SUPPORT
void serial_flush(void)
{
if (!gd->cur_serial_dev)
return;
_serial_flush(gd->cur_serial_dev);
}
#endif
int serial_getc(void)
{
if (!gd->cur_serial_dev)
return 0;
return _serial_getc(gd->cur_serial_dev);
}
int serial_tstc(void)
{
if (!gd->cur_serial_dev)
return 0;
return _serial_tstc(gd->cur_serial_dev);
}
void serial_setbrg(void)
{
struct dm_serial_ops *ops;
if (!gd->cur_serial_dev)
return;
ops = serial_get_ops(gd->cur_serial_dev);
if (ops->setbrg)
ops->setbrg(gd->cur_serial_dev, gd->baudrate);
}
int serial_getconfig(struct udevice *dev, uint *config)
{
struct dm_serial_ops *ops;
ops = serial_get_ops(dev);
if (ops->getconfig)
return ops->getconfig(dev, config);
return 0;
}
int serial_setconfig(struct udevice *dev, uint config)
{
struct dm_serial_ops *ops;
ops = serial_get_ops(dev);
if (ops->setconfig)
return ops->setconfig(dev, config);
return 0;
}
int serial_getinfo(struct udevice *dev, struct serial_device_info *info)
{
struct dm_serial_ops *ops;
if (!info)
return -EINVAL;
info->baudrate = gd->baudrate;
ops = serial_get_ops(dev);
if (ops->getinfo)
return ops->getinfo(dev, info);
return -EINVAL;
}
void serial_stdio_init(void)
{
}
#if defined(CONFIG_DM_STDIO)
#if CONFIG_IS_ENABLED(SERIAL_PRESENT)
static void serial_stub_putc(struct stdio_dev *sdev, const char ch)
{
_serial_putc(sdev->priv, ch);
}
static void serial_stub_puts(struct stdio_dev *sdev, const char *str)
{
_serial_puts(sdev->priv, str);
}
#ifdef CONFIG_CONSOLE_FLUSH_SUPPORT
static void serial_stub_flush(struct stdio_dev *sdev)
{
_serial_flush(sdev->priv);
}
#endif
static int serial_stub_getc(struct stdio_dev *sdev)
{
return _serial_getc(sdev->priv);
}
static int serial_stub_tstc(struct stdio_dev *sdev)
{
return _serial_tstc(sdev->priv);
}
#endif
#endif
/**
* on_baudrate() - Update the actual baudrate when the env var changes
*
* This will check for a valid baudrate and only apply it if valid.
*/
static int on_baudrate(const char *name, const char *value, enum env_op op,
int flags)
{
int i;
int baudrate;
switch (op) {
case env_op_create:
case env_op_overwrite:
/*
* Switch to new baudrate if new baudrate is supported
*/
baudrate = dectoul(value, NULL);
/* Not actually changing */
if (gd->baudrate == baudrate)
return 0;
for (i = 0; i < ARRAY_SIZE(baudrate_table); ++i) {
if (baudrate == baudrate_table[i])
break;
}
if (i == ARRAY_SIZE(baudrate_table)) {
if ((flags & H_FORCE) == 0)
printf("## Baudrate %d bps not supported\n",
baudrate);
return 1;
}
if ((flags & H_INTERACTIVE) != 0) {
printf("## Switch baudrate to %d bps and press ENTER ...\n",
baudrate);
udelay(50000);
flush();
}
gd->baudrate = baudrate;
serial_setbrg();
udelay(50000);
if ((flags & H_INTERACTIVE) != 0)
while (1) {
if (getchar() == '\r')
break;
}
return 0;
case env_op_delete:
printf("## Baudrate may not be deleted\n");
return 1;
default:
return 0;
}
}
U_BOOT_ENV_CALLBACK(baudrate, on_baudrate);
#if CONFIG_IS_ENABLED(SERIAL_PRESENT)
static int serial_post_probe(struct udevice *dev)
{
struct dm_serial_ops *ops = serial_get_ops(dev);
#ifdef CONFIG_DM_STDIO
struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
struct stdio_dev sdev;
#endif
int ret;
#if defined(CONFIG_NEEDS_MANUAL_RELOC)
if (ops->setbrg)
ops->setbrg += gd->reloc_off;
if (ops->getc)
ops->getc += gd->reloc_off;
if (ops->putc)
ops->putc += gd->reloc_off;
if (ops->pending)
ops->pending += gd->reloc_off;
if (ops->clear)
ops->clear += gd->reloc_off;
if (ops->getconfig)
ops->getconfig += gd->reloc_off;
if (ops->setconfig)
ops->setconfig += gd->reloc_off;
#if CONFIG_POST & CONFIG_SYS_POST_UART
if (ops->loop)
ops->loop += gd->reloc_off;
#endif
if (ops->getinfo)
ops->getinfo += gd->reloc_off;
#endif
/* Set the baud rate */
if (ops->setbrg) {
ret = ops->setbrg(dev, gd->baudrate);
if (ret)
return ret;
}
#ifdef CONFIG_DM_STDIO
if (!(gd->flags & GD_FLG_RELOC))
return 0;
memset(&sdev, '\0', sizeof(sdev));
strncpy(sdev.name, dev->name, sizeof(sdev.name));
sdev.flags = DEV_FLAGS_OUTPUT | DEV_FLAGS_INPUT | DEV_FLAGS_DM;
sdev.priv = dev;
sdev.putc = serial_stub_putc;
sdev.puts = serial_stub_puts;
STDIO_DEV_ASSIGN_FLUSH(&sdev, serial_stub_flush);
sdev.getc = serial_stub_getc;
sdev.tstc = serial_stub_tstc;
#if CONFIG_IS_ENABLED(SERIAL_RX_BUFFER)
/* Allocate the RX buffer */
upriv->buf = malloc(CONFIG_SERIAL_RX_BUFFER_SIZE);
#endif
stdio_register_dev(&sdev, &upriv->sdev);
#endif
return 0;
}
static int serial_pre_remove(struct udevice *dev)
{
#if CONFIG_IS_ENABLED(SYS_STDIO_DEREGISTER)
struct serial_dev_priv *upriv = dev_get_uclass_priv(dev);
if (stdio_deregister_dev(upriv->sdev, true))
return -EPERM;
#endif
return 0;
}
UCLASS_DRIVER(serial) = {
.id = UCLASS_SERIAL,
.name = "serial",
.flags = DM_UC_FLAG_SEQ_ALIAS,
.post_probe = serial_post_probe,
.pre_remove = serial_pre_remove,
.per_device_auto = sizeof(struct serial_dev_priv),
};
#endif