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authorLinus Torvalds <torvalds@linux-foundation.org>2013-04-29 20:18:34 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2013-04-29 20:18:34 +0200
commit4f567cbc957a7cffd1a428a000d93bd903f42349 (patch)
treee648bfed3732a23031a32811b20975827dad62d2 /Documentation
parentMerge tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/... (diff)
parentTools: hv: Fix a checkpatch warning (diff)
downloadlinux-4f567cbc957a7cffd1a428a000d93bd903f42349.tar.xz
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Merge tag 'char-misc-3.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver update from Greg Kroah-Hartman: "Here's the big char / misc driver update for 3.10-rc1 A number of various driver updates, the majority being new functionality in the MEI driver subsystem (it's now a subsystem, it started out just a single driver), extcon updates, memory updates, hyper-v updates, and a bunch of other small stuff that doesn't fit in any other tree. All of these have been in linux-next for a while" * tag 'char-misc-3.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (148 commits) Tools: hv: Fix a checkpatch warning tools: hv: skip iso9660 mounts in hv_vss_daemon tools: hv: use FIFREEZE/FITHAW in hv_vss_daemon tools: hv: use getmntent in hv_vss_daemon Tools: hv: Fix a checkpatch warning tools: hv: fix checks for origin of netlink message in hv_vss_daemon Tools: hv: fix warnings in hv_vss_daemon misc: mark spear13xx-pcie-gadget as broken mei: fix krealloc() misuse in in mei_cl_irq_read_msg() mei: reduce flow control only for completed messages mei: reseting -> resetting mei: fix reading large reposnes mei: revamp mei_irq_read_client_message function mei: revamp mei_amthif_irq_read_message mei: revamp hbm state machine Revert "drivers/scsi: use module_pcmcia_driver() in pcmcia drivers" Revert "scsi: pcmcia: nsp_cs: remove module init/exit function prototypes" scsi: pcmcia: nsp_cs: remove module init/exit function prototypes mei: wd: fix line over 80 characters misc: tsl2550: Use dev_pm_ops ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/ABI/testing/sysfs-bus-mei7
-rw-r--r--Documentation/devicetree/bindings/arm/msm/ssbi.txt18
-rw-r--r--Documentation/misc-devices/mei/mei-client-bus.txt138
3 files changed, 163 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-mei b/Documentation/ABI/testing/sysfs-bus-mei
new file mode 100644
index 000000000000..2066f0bbd453
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-mei
@@ -0,0 +1,7 @@
+What: /sys/bus/mei/devices/.../modalias
+Date: March 2013
+KernelVersion: 3.10
+Contact: Samuel Ortiz <sameo@linux.intel.com>
+ linux-mei@linux.intel.com
+Description: Stores the same MODALIAS value emitted by uevent
+ Format: mei:<mei device name>
diff --git a/Documentation/devicetree/bindings/arm/msm/ssbi.txt b/Documentation/devicetree/bindings/arm/msm/ssbi.txt
new file mode 100644
index 000000000000..54fd5ced3401
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/msm/ssbi.txt
@@ -0,0 +1,18 @@
+* Qualcomm SSBI
+
+Some Qualcomm MSM devices contain a point-to-point serial bus used to
+communicate with a limited range of devices (mostly power management
+chips).
+
+These require the following properties:
+
+- compatible: "qcom,ssbi"
+
+- qcom,controller-type
+ indicates the SSBI bus variant the controller should use to talk
+ with the slave device. This should be one of "ssbi", "ssbi2", or
+ "pmic-arbiter". The type chosen is determined by the attached
+ slave.
+
+The slave device should be the single child node of the ssbi device
+with a compatible field.
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 000000000000..f83910a8ce76
--- /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);
+ }
+}