Document sysfs files/directories/symlinks exposed by the I3C subsystem. Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxx> Reviewed-by: Arnd Bergmann <arnd@xxxxxxxx> --- Changes in v9: - Add Arnd's R-b Changes in v8: - None Changes in v7: - Bump KernelVersion to 4.20 - Add new entries under i3c-<bus-id> now that the master controller is no longer represented as a device under this directory but implicitly represented by the bus object Changes in v6: - none Changes in v5: - Fix the kernel version - Rename address into dynamic_address to match changes done in the code Changes in v4: - none Changes in v3: - none Changes in v2: - new patch --- Documentation/ABI/testing/sysfs-bus-i3c | 146 ++++++++++++++++++++++++ 1 file changed, 146 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-bus-i3c diff --git a/Documentation/ABI/testing/sysfs-bus-i3c b/Documentation/ABI/testing/sysfs-bus-i3c new file mode 100644 index 000000000000..d7c7485b0c17 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-i3c @@ -0,0 +1,146 @@ +What: /sys/bus/i3c/devices/i3c-<bus-id> +KernelVersion: 4.20 +Contact: linux-i3c@xxxxxxxxxxxxxxx +Description: + An I3C bus. This directory will contain one sub-directory per + I3C device present on the bus. + +What: /sys/bus/i3c/devices/i3c-<bus-id>/current_master +KernelVersion: 4.20 +Contact: linux-i3c@xxxxxxxxxxxxxxx +Description: + Expose the master that owns the bus (<bus-id>-<master-pid>) at + the time this file is read. Note that bus ownership can change + overtime, so there's no guarantee that when the read() call + returns, the value returned is still valid. + +What: /sys/bus/i3c/devices/i3c-<bus-id>/mode +KernelVersion: 4.20 +Contact: linux-i3c@xxxxxxxxxxxxxxx +Description: + I3C bus mode. Can be "pure", "mixed-fast" or "mixed-slow". See + the I3C specification for a detailed description of what each + of these modes implies. + +What: /sys/bus/i3c/devices/i3c-<bus-id>/i3c_scl_frequency +KernelVersion: 4.20 +Contact: linux-i3c@xxxxxxxxxxxxxxx +Description: + The frequency (expressed in Hz) of the SCL signal when + operating in I3C SDR mode. + +What: /sys/bus/i3c/devices/i3c-<bus-id>/i2c_scl_frequency +KernelVersion: 4.20 +Contact: linux-i3c@xxxxxxxxxxxxxxx +Description: + The frequency (expressed in Hz) of the SCL signal when + operating in I2C mode. + +What: /sys/bus/i3c/devices/i3c-<bus-id>/dynamic_address +KernelVersion: 4.20 +Contact: linux-i3c@xxxxxxxxxxxxxxx +Description: + Dynamic address assigned to the master controller. This + address may change if the bus is re-initialized. + +What: /sys/bus/i3c/devices/i3c-<bus-id>/bcr +KernelVersion: 4.20 +Contact: linux-i3c@xxxxxxxxxxxxxxx +Description: + BCR stands for Bus Characteristics Register and express the + device capabilities in term of speed, maximum read/write + length, etc. See the I3C specification for more details. + This entry describes the BCR of the master controller driving + the bus. + +What: /sys/bus/i3c/devices/i3c-<bus-id>/dcr +KernelVersion: 4.20 +Contact: linux-i3c@xxxxxxxxxxxxxxx +Description: + DCR stands for Device Characteristics Register and express the + device capabilities in term of exposed features. See the I3C + specification for more details. + This entry describes the DCR of the master controller driving + the bus. + +What: /sys/bus/i3c/devices/i3c-<bus-id>/pid +KernelVersion: 4.20 +Contact: linux-i3c@xxxxxxxxxxxxxxx +Description: + PID stands for Provisional ID and is used to uniquely identify + a device on a bus. This PID contains information about the + vendor, the part and an instance ID so that several devices of + the same type can be connected on the same bus. + See the I3C specification for more details. + This entry describes the PID of the master controller driving + the bus. + +What: /sys/bus/i3c/devices/i3c-<bus-id>/hdrcap +KernelVersion: 4.20 +Contact: linux-i3c@xxxxxxxxxxxxxxx +Description: + Expose the HDR (High Data Rate) capabilities of a device. + Returns a list of supported HDR mode, each element is separated + by space. Modes can be "hdr-ddr", "hdr-tsp" and "hdr-tsl". + See the I3C specification for more details about these HDR + modes. + This entry describes the HDRCAP of the master controller + driving the bus. + +What: /sys/bus/i3c/devices/i3c-<bus-id>/<bus-id>-<device-pid> +KernelVersion: 4.20 +Contact: linux-i3c@xxxxxxxxxxxxxxx +Description: + An I3C device present on I3C bus identified by <bus-id>. Note + that all devices are represented including the master driving + the bus. + +What: /sys/bus/i3c/devices/i3c-<bus-id>/<bus-id>-<device-pid>/dynamic_address +KernelVersion: 4.20 +Contact: linux-i3c@xxxxxxxxxxxxxxx +Description: + Dynamic address assigned to device <bus-id>-<device-pid>. This + address may change if the bus is re-initialized. + +What: /sys/bus/i3c/devices/i3c-<bus-id>/<bus-id>-<device-pid>/bcr +KernelVersion: 4.20 +Contact: linux-i3c@xxxxxxxxxxxxxxx +Description: + BCR stands for Bus Characteristics Register and express the + device capabilities in term of speed, maximum read/write + length, etc. See the I3C specification for more details. + +What: /sys/bus/i3c/devices/i3c-<bus-id>/<bus-id>-<device-pid>/dcr +KernelVersion: 4.20 +Contact: linux-i3c@xxxxxxxxxxxxxxx +Description: + DCR stands for Device Characteristics Register and express the + device capabilities in term of exposed features. See the I3C + specification for more details. + +What: /sys/bus/i3c/devices/i3c-<bus-id>/<bus-id>-<device-pid>/pid +KernelVersion: 4.20 +Contact: linux-i3c@xxxxxxxxxxxxxxx +Description: + PID stands for Provisional ID and is used to uniquely identify + a device on a bus. This PID contains information about the + vendor, the part and an instance ID so that several devices of + the same type can be connected on the same bus. + See the I3C specification for more details. + +What: /sys/bus/i3c/devices/i3c-<bus-id>/<bus-id>-<device-pid>/hdrcap +KernelVersion: 4.20 +Contact: linux-i3c@xxxxxxxxxxxxxxx +Description: + Expose the HDR (High Data Rate) capabilities of a device. + Returns a list of supported HDR mode, each element is separated + by space. Modes can be "hdr-ddr", "hdr-tsp" and "hdr-tsl". + See the I3C specification for more details about these HDR + modes. + +What: /sys/bus/i3c/devices/<bus-id>-<device-pid> +KernelVersion: 4.20 +Contact: linux-i3c@xxxxxxxxxxxxxxx +Description: + These directories are just symbolic links to + /sys/bus/i3c/devices/i3c-<bus-id>/<bus-id>-<device-pid>. -- 2.17.1
