linux-stable/include/linux/scmi_protocol.h
Sudeep Holla 933c504424 firmware: arm_scmi: add scmi protocol bus to enumerate protocol devices
The SCMI specification encompasses various protocols. However, not every
protocol has to be present on a given platform/implementation as not
every protocol is relevant for it.

Furthermore, the platform chooses which protocols it exposes to a given
agent. The only protocol that must be implemented is the base protocol.
The base protocol is used by an agent to discover which protocols are
available to it.

In order to enumerate the discovered implemented protocols, this patch
adds support for a separate scmi protocol bus. It also adds mechanism to
register support for different protocols.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2018-02-28 16:37:57 +00:00

117 lines
3.3 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* SCMI Message Protocol driver header
*
* Copyright (C) 2018 ARM Ltd.
*/
#include <linux/device.h>
#include <linux/types.h>
#define SCMI_MAX_STR_SIZE 16
/**
* struct scmi_revision_info - version information structure
*
* @major_ver: Major ABI version. Change here implies risk of backward
* compatibility break.
* @minor_ver: Minor ABI version. Change here implies new feature addition,
* or compatible change in ABI.
* @num_protocols: Number of protocols that are implemented, excluding the
* base protocol.
* @num_agents: Number of agents in the system.
* @impl_ver: A vendor-specific implementation version.
* @vendor_id: A vendor identifier(Null terminated ASCII string)
* @sub_vendor_id: A sub-vendor identifier(Null terminated ASCII string)
*/
struct scmi_revision_info {
u16 major_ver;
u16 minor_ver;
u8 num_protocols;
u8 num_agents;
u32 impl_ver;
char vendor_id[SCMI_MAX_STR_SIZE];
char sub_vendor_id[SCMI_MAX_STR_SIZE];
};
/**
* struct scmi_handle - Handle returned to ARM SCMI clients for usage.
*
* @dev: pointer to the SCMI device
* @version: pointer to the structure containing SCMI version information
*/
struct scmi_handle {
struct device *dev;
struct scmi_revision_info *version;
};
enum scmi_std_protocol {
SCMI_PROTOCOL_BASE = 0x10,
SCMI_PROTOCOL_POWER = 0x11,
SCMI_PROTOCOL_SYSTEM = 0x12,
SCMI_PROTOCOL_PERF = 0x13,
SCMI_PROTOCOL_CLOCK = 0x14,
SCMI_PROTOCOL_SENSOR = 0x15,
};
struct scmi_device {
u32 id;
u8 protocol_id;
struct device dev;
struct scmi_handle *handle;
};
#define to_scmi_dev(d) container_of(d, struct scmi_device, dev)
struct scmi_device *
scmi_device_create(struct device_node *np, struct device *parent, int protocol);
void scmi_device_destroy(struct scmi_device *scmi_dev);
struct scmi_device_id {
u8 protocol_id;
};
struct scmi_driver {
const char *name;
int (*probe)(struct scmi_device *sdev);
void (*remove)(struct scmi_device *sdev);
const struct scmi_device_id *id_table;
struct device_driver driver;
};
#define to_scmi_driver(d) container_of(d, struct scmi_driver, driver)
#ifdef CONFIG_ARM_SCMI_PROTOCOL
int scmi_driver_register(struct scmi_driver *driver,
struct module *owner, const char *mod_name);
void scmi_driver_unregister(struct scmi_driver *driver);
#else
static inline int
scmi_driver_register(struct scmi_driver *driver, struct module *owner,
const char *mod_name)
{
return -EINVAL;
}
static inline void scmi_driver_unregister(struct scmi_driver *driver) {}
#endif /* CONFIG_ARM_SCMI_PROTOCOL */
#define scmi_register(driver) \
scmi_driver_register(driver, THIS_MODULE, KBUILD_MODNAME)
#define scmi_unregister(driver) \
scmi_driver_unregister(driver)
/**
* module_scmi_driver() - Helper macro for registering a scmi driver
* @__scmi_driver: scmi_driver structure
*
* Helper macro for scmi drivers to set up proper module init / exit
* functions. Replaces module_init() and module_exit() and keeps people from
* printing pointless things to the kernel log when their driver is loaded.
*/
#define module_scmi_driver(__scmi_driver) \
module_driver(__scmi_driver, scmi_register, scmi_unregister)
typedef int (*scmi_prot_init_fn_t)(struct scmi_handle *);
int scmi_protocol_register(int protocol_id, scmi_prot_init_fn_t fn);
void scmi_protocol_unregister(int protocol_id);