diff options
Diffstat (limited to 'Documentation/misc-devices')
| -rw-r--r-- | Documentation/misc-devices/eeprom | 2 | ||||
| -rw-r--r-- | Documentation/misc-devices/lis3lv02d | 3 | ||||
| -rw-r--r-- | Documentation/misc-devices/mei/mei-amt-version.c | 6 | ||||
| -rw-r--r-- | Documentation/misc-devices/mei/mei-client-bus.txt | 138 | ||||
| -rw-r--r-- | Documentation/misc-devices/mei/mei.txt | 16 |
5 files changed, 151 insertions, 14 deletions
diff --git a/Documentation/misc-devices/eeprom b/Documentation/misc-devices/eeprom index f7e8104b576..ba692011f22 100644 --- a/Documentation/misc-devices/eeprom +++ b/Documentation/misc-devices/eeprom @@ -38,7 +38,7 @@ Supported chips: Authors: Frodo Looijaard <frodol@dds.nl>, Philip Edelbrock <phil@netroedge.com>, - Jean Delvare <khali@linux-fr.org>, + Jean Delvare <jdelvare@suse.de>, Greg Kroah-Hartman <greg@kroah.com>, IBM Corp. diff --git a/Documentation/misc-devices/lis3lv02d b/Documentation/misc-devices/lis3lv02d index f1a4ec840f8..af815b9ba41 100644 --- a/Documentation/misc-devices/lis3lv02d +++ b/Documentation/misc-devices/lis3lv02d @@ -4,7 +4,8 @@ Kernel driver lis3lv02d Supported chips: * STMicroelectronics LIS3LV02DL, LIS3LV02DQ (12 bits precision) - * STMicroelectronics LIS302DL, LIS3L02DQ, LIS331DL (8 bits) + * STMicroelectronics LIS302DL, LIS3L02DQ, LIS331DL (8 bits) and + LIS331DLH (16 bits) Authors: Yan Burman <burman.yan@gmail.com> diff --git a/Documentation/misc-devices/mei/mei-amt-version.c b/Documentation/misc-devices/mei/mei-amt-version.c index 01804f21631..57d0d871dcf 100644 --- a/Documentation/misc-devices/mei/mei-amt-version.c +++ b/Documentation/misc-devices/mei/mei-amt-version.c @@ -115,8 +115,6 @@ static bool mei_init(struct mei *me, const uuid_le *guid, struct mei_client *cl; struct mei_connect_client_data data; - mei_deinit(me); - me->verbose = verbose; me->fd = open("/dev/mei", O_RDWR); @@ -214,7 +212,7 @@ out: } /*************************************************************************** - * Intel Advanced Management Technolgy ME Client + * Intel Advanced Management Technology ME Client ***************************************************************************/ #define AMT_MAJOR_VERSION 1 @@ -256,7 +254,7 @@ struct amt_code_versions { } __attribute__((packed)); /*************************************************************************** - * Intel Advanced Management Technolgy Host Interface + * Intel Advanced Management Technology Host Interface ***************************************************************************/ struct amt_host_if_msg_header { diff --git a/Documentation/misc-devices/mei/mei-client-bus.txt b/Documentation/misc-devices/mei/mei-client-bus.txt new file mode 100644 index 00000000000..f83910a8ce7 --- /dev/null +++ b/Documentation/misc-devices/mei/mei-client-bus.txt @@ -0,0 +1,138 @@ +Intel(R) Management Engine (ME) Client bus API +=============================================== + + +Rationale +========= +MEI misc character device is useful for dedicated applications to send and receive +data to the many FW appliance found in Intel's ME from the user space. +However for some of the ME functionalities it make sense to leverage existing software +stack and expose them through existing kernel subsystems. + +In order to plug seamlessly into the kernel device driver model we add kernel virtual +bus abstraction on top of the MEI driver. This allows implementing linux kernel drivers +for the various MEI features as a stand alone entities found in their respective subsystem. +Existing device drivers can even potentially be re-used by adding an MEI CL bus layer to +the existing code. + + +MEI CL bus API +=========== +A driver implementation for an MEI Client is very similar to existing bus +based device drivers. The driver registers itself as an MEI CL bus driver through +the mei_cl_driver structure: + +struct mei_cl_driver { + struct device_driver driver; + const char *name; + + const struct mei_cl_device_id *id_table; + + int (*probe)(struct mei_cl_device *dev, const struct mei_cl_id *id); + int (*remove)(struct mei_cl_device *dev); +}; + +struct mei_cl_id { + char name[MEI_NAME_SIZE]; + kernel_ulong_t driver_info; +}; + +The mei_cl_id structure allows the driver to bind itself against a device name. + +To actually register a driver on the ME Client bus one must call the mei_cl_add_driver() +API. This is typically called at module init time. + +Once registered on the ME Client bus, a driver will typically try to do some I/O on +this bus and this should be done through the mei_cl_send() and mei_cl_recv() +routines. The latter is synchronous (blocks and sleeps until data shows up). +In order for drivers to be notified of pending events waiting for them (e.g. +an Rx event) they can register an event handler through the +mei_cl_register_event_cb() routine. Currently only the MEI_EVENT_RX event +will trigger an event handler call and the driver implementation is supposed +to call mei_recv() from the event handler in order to fetch the pending +received buffers. + + +Example +======= +As a theoretical example let's pretend the ME comes with a "contact" NFC IP. +The driver init and exit routines for this device would look like: + +#define CONTACT_DRIVER_NAME "contact" + +static struct mei_cl_device_id contact_mei_cl_tbl[] = { + { CONTACT_DRIVER_NAME, }, + + /* required last entry */ + { } +}; +MODULE_DEVICE_TABLE(mei_cl, contact_mei_cl_tbl); + +static struct mei_cl_driver contact_driver = { + .id_table = contact_mei_tbl, + .name = CONTACT_DRIVER_NAME, + + .probe = contact_probe, + .remove = contact_remove, +}; + +static int contact_init(void) +{ + int r; + + r = mei_cl_driver_register(&contact_driver); + if (r) { + pr_err(CONTACT_DRIVER_NAME ": driver registration failed\n"); + return r; + } + + return 0; +} + +static void __exit contact_exit(void) +{ + mei_cl_driver_unregister(&contact_driver); +} + +module_init(contact_init); +module_exit(contact_exit); + +And the driver's simplified probe routine would look like that: + +int contact_probe(struct mei_cl_device *dev, struct mei_cl_device_id *id) +{ + struct contact_driver *contact; + + [...] + mei_cl_enable_device(dev); + + mei_cl_register_event_cb(dev, contact_event_cb, contact); + + return 0; + } + +In the probe routine the driver first enable the MEI device and then registers +an ME bus event handler which is as close as it can get to registering a +threaded IRQ handler. +The handler implementation will typically call some I/O routine depending on +the pending events: + +#define MAX_NFC_PAYLOAD 128 + +static void contact_event_cb(struct mei_cl_device *dev, u32 events, + void *context) +{ + struct contact_driver *contact = context; + + if (events & BIT(MEI_EVENT_RX)) { + u8 payload[MAX_NFC_PAYLOAD]; + int payload_size; + + payload_size = mei_recv(dev, payload, MAX_NFC_PAYLOAD); + if (payload_size <= 0) + return; + + /* Hook to the NFC subsystem */ + nfc_hci_recv_frame(contact->hdev, payload, payload_size); + } +} diff --git a/Documentation/misc-devices/mei/mei.txt b/Documentation/misc-devices/mei/mei.txt index 2785697da59..15bba1aeba9 100644 --- a/Documentation/misc-devices/mei/mei.txt +++ b/Documentation/misc-devices/mei/mei.txt @@ -50,25 +50,25 @@ Intel MEI Driver The driver exposes a misc device called /dev/mei. An application maintains communication with an Intel ME feature while -/dev/mei is open. The binding to a specific features is performed by calling +/dev/mei is open. The binding to a specific feature is performed by calling MEI_CONNECT_CLIENT_IOCTL, which passes the desired UUID. The number of instances of an Intel ME feature that can be opened at the same time depends on the Intel ME feature, but most of the features allow only a single instance. The Intel AMT Host Interface (Intel AMTHI) feature supports multiple -simultaneous user applications. Therefore, the Intel MEI driver handles -this internally by maintaining request queues for the applications. +simultaneous user connected applications. The Intel MEI driver +handles this internally by maintaining request queues for the applications. -The driver is oblivious to data that is passed between firmware feature +The driver is transparent to data that are passed between firmware feature and host application. Because some of the Intel ME features can change the system configuration, the driver by default allows only a privileged user to access it. -A code snippet for an application communicating with -Intel AMTHI client: +A code snippet for an application communicating with Intel AMTHI client: + struct mei_connect_client_data data; fd = open(MEI_DEVICE); @@ -120,7 +120,7 @@ The Intel MEI Driver supports the following IOCTL command: Notes: max_msg_length (MTU) in client properties describes the maximum data that can be sent or received. (e.g. if MTU=2K, can send - requests up to bytes 2k and received responses upto 2k bytes). + requests up to bytes 2k and received responses up to 2k bytes). Intel ME Applications: ============== @@ -185,7 +185,7 @@ The Intel AMT Watchdog is composed of two parts: 2) Intel MEI driver - connects to the watchdog feature, configures the watchdog and sends the heartbeats. -The Intel MEI driver uses the kernel watchdog to configure the Intel AMT +The Intel MEI driver uses the kernel watchdog API to configure the Intel AMT Watchdog and to send heartbeats to it. The default timeout of the watchdog is 120 seconds. |