On Wed, Apr 03, 2013 at 10:05:49AM +0800, Lv Zheng wrote: > ACPI 5.0 specification introduces mechanisms of enumerating the peripherals > connected on the serial buses. It will look like: > Device (BTH0) > { > Name (_HID, "IBMF001") // _HID: Hardware ID > Name (_CID, "PNPF001") // _CID: Compatible ID > Method (_CRS, 0, NotSerialized) // _CRS: Current Resource Settings > { > Name (UBUF, ResourceTemplate () > { > UartSerialBus (0x0001C200, DataBitsEight, StopBitsOne, > 0xC0, LittleEndian, ParityTypeNone, FlowControlHardware, > 0x0020, 0x0020, "\\_SB.PCI0.UA00", > 0x00, ResourceConsumer, , > ) > } > Return (UBUF) > } > } > This patch follows the specification, implementing such UART enumeration > machanism by exporting current peripheral HID/CIDs for the UART devices. > A userspace udev rule may look like: > SUBSYSTEM=tty, ATTR{peripheral_type}=="*:IBMF001:*", > RUN+="/bin/userprog --devpath=%p" > Thanks for the internal composers: > Mika Westerberg <mika.westerberg@xxxxxxxxx> > Huang Ying <ying.huang@xxxxxxxxx> > Zhang Rui <rui.zhang@xxxxxxxxx> > Thanks for the internal reviewers: > Alan Cox <alan@xxxxxxxxxxxxxxx> > Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> > Heikki Krogerus <heikki.krogerus@xxxxxxxxx> > Andriy Shevchenko <andriy.shevchenko@xxxxxxxxx> > Fengguang Wu <fengguang.wu@xxxxxxxxx> Why are these names not on the list below? > Signed-off-by: Lv Zheng <lv.zheng@xxxxxxxxx> > Signed-off-by: Zhang Rui <rui.zhang@xxxxxxxxx> > Acked-by: Huang Ying <ying.huang@xxxxxxxxx> > Reviewed-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> > --- > drivers/acpi/Kconfig | 6 ++ > drivers/acpi/Makefile | 1 + > drivers/acpi/acpi_uart.c | 135 ++++++++++++++++++++++++++++++++++++++ > drivers/acpi/internal.h | 2 + > drivers/acpi/scan.c | 8 +-- > drivers/tty/serial/serial_core.c | 15 +++++ > include/linux/tty.h | 11 ++++ > 7 files changed, 174 insertions(+), 4 deletions(-) > create mode 100644 drivers/acpi/acpi_uart.c > > diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig > index 92ed969..42233f6 100644 > --- a/drivers/acpi/Kconfig > +++ b/drivers/acpi/Kconfig > @@ -186,6 +186,12 @@ config ACPI_I2C > help > ACPI I2C enumeration support. > > +config ACPI_UART > + def_tristate TTY > + depends on TTY > + help > + ACPI UART enumeration support. Please provide more information here. As this is primarily an ACPI patch, I need an ack from a ACPI maintainer before I can take this. > + > config ACPI_PROCESSOR > tristate "Processor" > select THERMAL > diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile > index 474fcfe..4db5470 100644 > --- a/drivers/acpi/Makefile > +++ b/drivers/acpi/Makefile > @@ -72,6 +72,7 @@ obj-$(CONFIG_ACPI_EC_DEBUGFS) += ec_sys.o > obj-$(CONFIG_ACPI_CUSTOM_METHOD)+= custom_method.o > obj-$(CONFIG_ACPI_BGRT) += bgrt.o > obj-$(CONFIG_ACPI_I2C) += acpi_i2c.o > +obj-$(CONFIG_ACPI_UART) += acpi_uart.o > > # processor has its own "processor." module_param namespace > processor-y := processor_driver.o processor_throttling.o > diff --git a/drivers/acpi/acpi_uart.c b/drivers/acpi/acpi_uart.c > new file mode 100644 > index 0000000..dd5ac2e > --- /dev/null > +++ b/drivers/acpi/acpi_uart.c > @@ -0,0 +1,135 @@ > +/* > + * acpi_uart.c - ACPI UART enumeration support > + * > + * Copyright (c) 2013, Intel Corporation > + * Author: Lv Zheng <lv.zheng@xxxxxxxxx> > + * > + * This program is free software; you can redistribute it and/or modify it > + * under the terms of the GNU General Public License as published by the > + * Free Software Foundation; version 2 of the License. > + */ > + > +#include <linux/init.h> > +#include <linux/tty.h> > +#include <linux/module.h> > +#include <linux/acpi.h> > + > +#include "internal.h" > + > +struct acpi_uart_buf { > + char *buf; > + size_t size; > + int *len; > +}; > + > +struct acpi_uart_enum { > + void *context; > + acpi_status status; > + > + struct acpi_device *adev; > +}; > + > +static acpi_status > +acpi_uart_enum_pnpids(struct acpi_device *adev, > + struct acpi_resource_uart_serialbus *sb, > + void *context); > + > +static int acpi_uart_enum_resources(struct acpi_resource *ares, > + void *context) > +{ > + struct acpi_uart_enum *ctx = context; > + struct acpi_resource_uart_serialbus *sb; > + > + if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) > + return 1; > + sb = &ares->data.uart_serial_bus; > + if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_UART) > + return 1; > + > + ctx->status = acpi_uart_enum_pnpids(ctx->adev, sb, ctx->context); > + return 1; > +} > + > +static acpi_status acpi_uart_enum_devices(acpi_handle handle, u32 level, > + void *context, > + void **return_value) > +{ > + struct acpi_uart_enum *ctx = context; > + struct acpi_device *adev; > + struct list_head resource_list; > + > + if (acpi_bus_get_device(handle, &adev)) > + return AE_OK; > + if (acpi_bus_get_status(adev) || !adev->status.present) > + return AE_OK; > + > + /* Enumerate resources. */ > + ctx->adev = adev; > + ctx->status = AE_OK; > + INIT_LIST_HEAD(&resource_list); > + acpi_dev_get_resources(adev, &resource_list, > + acpi_uart_enum_resources, ctx); > + acpi_dev_free_resource_list(&resource_list); > + > + return ctx->status; > +} > + > +static int acpi_uart_walk_port(struct device *parent, > + void *context) > +{ > + acpi_handle handle; > + acpi_status status; > + struct acpi_uart_enum ctx; > + > + handle = parent ? ACPI_HANDLE(parent) : NULL; > + if (!handle) > + return -ENODEV; > + > + ctx.context = context; > + > + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1, > + acpi_uart_enum_devices, NULL, > + &ctx, NULL); > + if (ACPI_FAILURE(status)) > + return -EINVAL; > + > + return 0; > +} > + > +static acpi_status > +acpi_uart_enum_pnpids(struct acpi_device *adev, > + struct acpi_resource_uart_serialbus *sb, > + void *context) > +{ > + int len; > + struct acpi_uart_buf *ctx = context; > + > + len = acpi_device_create_modalias(adev, ctx->buf, ctx->size); > + *ctx->len = len; > + > + return len < 0 ? AE_CTRL_DEPTH : AE_OK; > +} > + > +/** > + * acpi_uart_get_peripheral_type - get peripheral HID/CIDs > + * @dev: the tty class device > + * @buf: the string buffer containing HID/CIDs > + * @size: the size of the string buffer > + * > + * Obtain UART peripheral HID/CIDs. Return buffer size on success, > + * -errno on failure. > + */ > +int acpi_uart_get_peripheral_type(struct device *dev, > + char *buf, size_t size) > +{ > + int ret; > + int len = 0; > + struct acpi_uart_buf ctx = { buf, size, &len }; > + > + ret = acpi_uart_walk_port(dev->parent, &ctx); > + if (ret < 0) > + return ret; > + > + return len; > +} > +EXPORT_SYMBOL_GPL(acpi_uart_get_peripheral_type); > diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h > index 3c94a73..30d7440 100644 > --- a/drivers/acpi/internal.h > +++ b/drivers/acpi/internal.h > @@ -61,6 +61,8 @@ void acpi_init_device_object(struct acpi_device *device, acpi_handle handle, > int type, unsigned long long sta); > void acpi_device_add_finalize(struct acpi_device *device); > void acpi_free_ids(struct acpi_device *device); > +int acpi_device_create_modalias(struct acpi_device *acpi_dev, > + char *modalias, int size); > > /* -------------------------------------------------------------------------- > Power Resource > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c > index 5e7e991..0d7d49f 100644 > --- a/drivers/acpi/scan.c > +++ b/drivers/acpi/scan.c > @@ -68,8 +68,8 @@ int acpi_scan_add_handler(struct acpi_scan_handler *handler) > * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get: > * char *modalias: "acpi:IBM0001:ACPI0001" > */ > -static int create_modalias(struct acpi_device *acpi_dev, char *modalias, > - int size) > +int acpi_device_create_modalias(struct acpi_device *acpi_dev, > + char *modalias, int size) > { > int len; > int count; > @@ -99,7 +99,7 @@ acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, cha > int len; > > /* Device has no HID and no CID or string is >1024 */ > - len = create_modalias(acpi_dev, buf, 1024); > + len = acpi_device_create_modalias(acpi_dev, buf, 1024); > if (len <= 0) > return 0; > buf[len++] = '\n'; > @@ -567,7 +567,7 @@ static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env) > > if (add_uevent_var(env, "MODALIAS=")) > return -ENOMEM; > - len = create_modalias(acpi_dev, &env->buf[env->buflen - 1], > + len = acpi_device_create_modalias(acpi_dev, &env->buf[env->buflen - 1], > sizeof(env->buf) - env->buflen); > if (len >= (sizeof(env->buf) - env->buflen)) > return -ENOMEM; > diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c > index a400002..17e104e 100644 > --- a/drivers/tty/serial/serial_core.c > +++ b/drivers/tty/serial/serial_core.c > @@ -2515,6 +2515,19 @@ static ssize_t uart_get_attr_iomem_reg_shift(struct device *dev, > return snprintf(buf, PAGE_SIZE, "%d\n", tmp.iomem_reg_shift); > } > > +static ssize_t uart_get_attr_peripheral_type(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + int len; > + > + len = acpi_uart_get_peripheral_type(dev, buf, 1024); > + if (len > 0) { > + buf[len++] = '\n'; > + return len; > + } > + return snprintf(buf, PAGE_SIZE, "uart\n"); What is the "uart" part for? Isn't that kind of obvious? > +} You are creating a new sysfs file, you must create a new Documentation/ABI entry as well. > + > static DEVICE_ATTR(type, S_IRUSR | S_IRGRP, uart_get_attr_type, NULL); > static DEVICE_ATTR(line, S_IRUSR | S_IRGRP, uart_get_attr_line, NULL); > static DEVICE_ATTR(port, S_IRUSR | S_IRGRP, uart_get_attr_port, NULL); > @@ -2528,6 +2541,7 @@ static DEVICE_ATTR(custom_divisor, S_IRUSR | S_IRGRP, uart_get_attr_custom_divis > static DEVICE_ATTR(io_type, S_IRUSR | S_IRGRP, uart_get_attr_io_type, NULL); > static DEVICE_ATTR(iomem_base, S_IRUSR | S_IRGRP, uart_get_attr_iomem_base, NULL); > static DEVICE_ATTR(iomem_reg_shift, S_IRUSR | S_IRGRP, uart_get_attr_iomem_reg_shift, NULL); > +static DEVICE_ATTR(peripheral_type, S_IRUSR | S_IRGRP, uart_get_attr_peripheral_type, NULL); > > static struct attribute *tty_dev_attrs[] = { > &dev_attr_type.attr, > @@ -2543,6 +2557,7 @@ static struct attribute *tty_dev_attrs[] = { > &dev_attr_io_type.attr, > &dev_attr_iomem_base.attr, > &dev_attr_iomem_reg_shift.attr, > + &dev_attr_peripheral_type.attr, > NULL, > }; > > diff --git a/include/linux/tty.h b/include/linux/tty.h > index 367a9df..723fdd01 100644 > --- a/include/linux/tty.h > +++ b/include/linux/tty.h > @@ -692,4 +692,15 @@ do { \ > } while (0) > > > +#ifdef CONFIG_ACPI_UART > +int acpi_uart_get_peripheral_type(struct device *dev, > + char *buf, size_t size); > +#else > +static inline int acpi_uart_get_peripheral_type(struct device *dev, > + char *buf, size_t size) > +{ > + return -ENODEV; > +} > +#endif I see you never tested this code without the configuration option enabled :( {sigh} greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html