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linux-sg2042/include/linux/sys_soc.h

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drivers/base: add bus for System-on-Chip devices Traditionally, any System-on-Chip based platform creates a flat list of platform_devices directly under /sys/devices/platform. In order to give these some better structure, this introduces a new bus type for soc_devices that are registered with the new soc_device_register() function. All devices that are on the same chip should then be registered as child devices of the soc device. The soc bus also exports a few standardised device attributes which allow user space to query the specific type of soc. Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-07 03:22:22 +08:00
/*
* Copyright (C) ST-Ericsson SA 2011
* Author: Lee Jones <lee.jones@linaro.org> for ST-Ericsson.
* License terms: GNU General Public License (GPL), version 2
*/
#ifndef __SOC_BUS_H
#define __SOC_BUS_H
#include <linux/device.h>
struct soc_device_attribute {
const char *machine;
const char *family;
const char *revision;
const char *soc_id;
base: soc: Introduce soc_device_match() interface We keep running into cases where device drivers want to know the exact version of the a SoC they are currently running on. In the past, this has usually been done through a vendor specific API that can be called by a driver, or by directly accessing some kind of version register that is not part of the device itself but that belongs to a global register area of the chip. Common reasons for doing this include: - A machine is not using devicetree or similar for passing data about on-chip devices, but just announces their presence using boot-time platform devices, and the machine code itself does not care about the revision. - There is existing firmware or boot loaders with existing DT binaries with generic compatible strings that do not identify the particular revision of each device, but the driver knows which SoC revisions include which part. - A prerelease version of a chip has some quirks and we are using the same version of the bootloader and the DT blob on both the prerelease and the final version. An update of the DT binding seems inappropriate because that would involve maintaining multiple copies of the dts and/or bootloader. This patch introduces the soc_device_match() interface that is meant to work like of_match_node() but instead of identifying the version of a device, it identifies the SoC itself using a vendor-agnostic interface. Unlike of_match_node(), we do not do an exact string compare but instead use glob_match() to allow wildcards in strings. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-21 14:57:19 +08:00
const void *data;
drivers/base: add bus for System-on-Chip devices Traditionally, any System-on-Chip based platform creates a flat list of platform_devices directly under /sys/devices/platform. In order to give these some better structure, this introduces a new bus type for soc_devices that are registered with the new soc_device_register() function. All devices that are on the same chip should then be registered as child devices of the soc device. The soc bus also exports a few standardised device attributes which allow user space to query the specific type of soc. Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-07 03:22:22 +08:00
};
/**
* soc_device_register - register SoC as a device
* @soc_plat_dev_attr: Attributes passed from platform to be attributed to a SoC
*/
struct soc_device *soc_device_register(
struct soc_device_attribute *soc_plat_dev_attr);
/**
* soc_device_unregister - unregister SoC device
* @dev: SoC device to be unregistered
*/
void soc_device_unregister(struct soc_device *soc_dev);
/**
* soc_device_to_device - helper function to fetch struct device
* @soc: Previously registered SoC device container
*/
struct device *soc_device_to_device(struct soc_device *soc);
base: soc: Provide a dummy implementation of soc_device_match() Provide a dummy implementation of soc_device_match(), to allow compiling drivers that may be used on SoCs both with and without CONFIG_SOC_BUS, and for compile testing. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
2016-10-26 21:13:15 +08:00
#ifdef CONFIG_SOC_BUS
base: soc: Introduce soc_device_match() interface We keep running into cases where device drivers want to know the exact version of the a SoC they are currently running on. In the past, this has usually been done through a vendor specific API that can be called by a driver, or by directly accessing some kind of version register that is not part of the device itself but that belongs to a global register area of the chip. Common reasons for doing this include: - A machine is not using devicetree or similar for passing data about on-chip devices, but just announces their presence using boot-time platform devices, and the machine code itself does not care about the revision. - There is existing firmware or boot loaders with existing DT binaries with generic compatible strings that do not identify the particular revision of each device, but the driver knows which SoC revisions include which part. - A prerelease version of a chip has some quirks and we are using the same version of the bootloader and the DT blob on both the prerelease and the final version. An update of the DT binding seems inappropriate because that would involve maintaining multiple copies of the dts and/or bootloader. This patch introduces the soc_device_match() interface that is meant to work like of_match_node() but instead of identifying the version of a device, it identifies the SoC itself using a vendor-agnostic interface. Unlike of_match_node(), we do not do an exact string compare but instead use glob_match() to allow wildcards in strings. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-21 14:57:19 +08:00
const struct soc_device_attribute *soc_device_match(
const struct soc_device_attribute *matches);
base: soc: Provide a dummy implementation of soc_device_match() Provide a dummy implementation of soc_device_match(), to allow compiling drivers that may be used on SoCs both with and without CONFIG_SOC_BUS, and for compile testing. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
2016-10-26 21:13:15 +08:00
#else
static inline const struct soc_device_attribute *soc_device_match(
const struct soc_device_attribute *matches) { return NULL; }
#endif
drivers/base: add bus for System-on-Chip devices Traditionally, any System-on-Chip based platform creates a flat list of platform_devices directly under /sys/devices/platform. In order to give these some better structure, this introduces a new bus type for soc_devices that are registered with the new soc_device_register() function. All devices that are on the same chip should then be registered as child devices of the soc device. The soc bus also exports a few standardised device attributes which allow user space to query the specific type of soc. Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-07 03:22:22 +08:00
#endif /* __SOC_BUS_H */