diff options
Diffstat (limited to 'drivers/serial/serial-uclass.c')
| -rw-r--r-- | drivers/serial/serial-uclass.c | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/drivers/serial/serial-uclass.c b/drivers/serial/serial-uclass.c new file mode 100644 index 0000000000..d04104e747 --- /dev/null +++ b/drivers/serial/serial-uclass.c @@ -0,0 +1,213 @@ +/* + * Copyright (c) 2014 The Chromium OS Authors. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <dm.h> +#include <errno.h> +#include <fdtdec.h> +#include <os.h> +#include <serial.h> +#include <stdio_dev.h> +#include <dm/lists.h> +#include <dm/device-internal.h> + +DECLARE_GLOBAL_DATA_PTR; + +/* The currently-selected console serial device */ +struct udevice *cur_dev __attribute__ ((section(".data"))); + +#ifndef CONFIG_SYS_MALLOC_F_LEN +#error "Serial is required before relocation - define CONFIG_SYS_MALLOC_F_LEN to make this work" +#endif + +static void serial_find_console_or_panic(void) +{ + int node; + + /* Check for a chosen console */ + node = fdtdec_get_chosen_node(gd->fdt_blob, "stdout-path"); + if (node < 0) + node = fdtdec_get_alias_node(gd->fdt_blob, "console"); + if (!uclass_get_device_by_of_offset(UCLASS_SERIAL, node, &cur_dev)) + return; + + /* + * If the console is not marked to be bound before relocation, bind + * it anyway. + */ + if (node > 0 && + !lists_bind_fdt(gd->dm_root, gd->fdt_blob, node, &cur_dev)) { + if (!device_probe(cur_dev)) + return; + cur_dev = NULL; + } + + /* + * Failing that, get the device with sequence number 0, or in extremis + * just the first serial device we can find. But we insist on having + * a console (even if it is silent). + */ + if (uclass_get_device_by_seq(UCLASS_SERIAL, 0, &cur_dev) && + (uclass_first_device(UCLASS_SERIAL, &cur_dev) || !cur_dev)) + panic("No serial driver found"); +} + +/* Called prior to relocation */ +int serial_init(void) +{ + serial_find_console_or_panic(); + gd->flags |= GD_FLG_SERIAL_READY; + + return 0; +} + +/* Called after relocation */ +void serial_initialize(void) +{ + serial_find_console_or_panic(); +} + +void serial_putc(char ch) +{ + struct dm_serial_ops *ops = serial_get_ops(cur_dev); + int err; + + do { + err = ops->putc(cur_dev, ch); + } while (err == -EAGAIN); + if (ch == '\n') + serial_putc('\r'); +} + +void serial_setbrg(void) +{ + struct dm_serial_ops *ops = serial_get_ops(cur_dev); + + if (ops->setbrg) + ops->setbrg(cur_dev, gd->baudrate); +} + +void serial_puts(const char *str) +{ + while (*str) + serial_putc(*str++); +} + +int serial_tstc(void) +{ + struct dm_serial_ops *ops = serial_get_ops(cur_dev); + + if (ops->pending) + return ops->pending(cur_dev, true); + + return 1; +} + +int serial_getc(void) +{ + struct dm_serial_ops *ops = serial_get_ops(cur_dev); + int err; + + do { + err = ops->getc(cur_dev); + } while (err == -EAGAIN); + + return err >= 0 ? err : 0; +} + +void serial_stdio_init(void) +{ +} + +void serial_stub_putc(struct stdio_dev *sdev, const char ch) +{ + struct udevice *dev = sdev->priv; + struct dm_serial_ops *ops = serial_get_ops(dev); + + ops->putc(dev, ch); +} + +void serial_stub_puts(struct stdio_dev *sdev, const char *str) +{ + while (*str) + serial_stub_putc(sdev, *str++); +} + +int serial_stub_getc(struct stdio_dev *sdev) +{ + struct udevice *dev = sdev->priv; + struct dm_serial_ops *ops = serial_get_ops(dev); + + int err; + + do { + err = ops->getc(dev); + } while (err == -EAGAIN); + + return err >= 0 ? err : 0; +} + +int serial_stub_tstc(struct stdio_dev *sdev) +{ + struct udevice *dev = sdev->priv; + struct dm_serial_ops *ops = serial_get_ops(dev); + + if (ops->pending) + return ops->pending(dev, true); + + return 1; +} + +static int serial_post_probe(struct udevice *dev) +{ + struct stdio_dev sdev; + struct dm_serial_ops *ops = serial_get_ops(dev); + struct serial_dev_priv *upriv = dev->uclass_priv; + int ret; + + /* Set the baud rate */ + if (ops->setbrg) { + ret = ops->setbrg(dev, gd->baudrate); + if (ret) + return ret; + } + + 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; + sdev.priv = dev; + sdev.putc = serial_stub_putc; + sdev.puts = serial_stub_puts; + sdev.getc = serial_stub_getc; + sdev.tstc = serial_stub_tstc; + stdio_register_dev(&sdev, &upriv->sdev); + + return 0; +} + +static int serial_pre_remove(struct udevice *dev) +{ +#ifdef CONFIG_SYS_STDIO_DEREGISTER + struct serial_dev_priv *upriv = dev->uclass_priv; + + if (stdio_deregister_dev(upriv->sdev)) + return -EPERM; +#endif + + return 0; +} + +UCLASS_DRIVER(serial) = { + .id = UCLASS_SERIAL, + .name = "serial", + .post_probe = serial_post_probe, + .pre_remove = serial_pre_remove, + .per_device_auto_alloc_size = sizeof(struct serial_dev_priv), +}; |