summaryrefslogtreecommitdiffstats
path: root/Documentation/userspace-api/dcdbas.rst
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
commitcf9610f9116d55c5a66ef9f1faecacabd93a9322 (patch)
tree757a3d280760c654767631cab5ad8af2d86d1848 /Documentation/userspace-api/dcdbas.rst
downloadlinux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.tar.gz
linux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.zip
Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
Pull pin control updates from Linus Walleij: "Core changes: - Use the non-blocking mux_state_try_select() in the generic MUX pin control back-end - Free pin maps on pinctrl_generic_to_map() failure in the core helpers New hardware pin control: - Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC (this is for the low power audio, LPASS = Low Power Audio SubSystem portions) - Upboard support on top of the Intel pin controller - Apple T6030 and T6031 support (just compatible strings) - Samsung Exynos 8855 SoC - Mediatek MT6858 SoC - Rockchip RK3308B and RV1106 SoCs - Airoha EN7523 and AN7563 SoCs Improvements: - Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable - Qualcomm improvements on top of the Qualcomm PDC (power domain controller) irqchip improvements from tglx:s tree - Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups - The NPCM8xx driver has been put into shape fixing many pin and group definitions - Some non-urgent Tegra 264 pin assignments are fixed up - Some non-urgent fixups to Airoha AN7581 and AN7583 registers and pin assignments, missing features etc" * tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits) dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema pinctrl: meson: sync some modify from A4 pinctrl: meson: a4: Add input enable pin configuration pinctrl: realtek: rtd1625: remove unused group name spdif_sel pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13 dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema Revert "Merge branch 'ib-rsk7204' into devel" pinctrl: rockchip: Add RV1106 pinctrl support dt-bindings: pinctrl: rockchip: Add RV1106 compatible pinctrl: rockchip: Decode drive strength in the get function pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable pinctrl: airoha: add support of an7563 SoC dt-bindings: pinctrl: airoha: add support of an7563 pin controller pinctrl: airoha: try to find chip scu node by phandle first pinctrl: airoha: add support of en7523 SoC dt-bindings: pinctrl: airoha: add support of en7523 pin controller pinctrl: airoha: an7583: add support for olt pinmux pinctrl: airoha: an7583: add support for pon_alt pinmux pinctrl: airoha: an7583: add support for npu_uart pinmux dt-bindings: pinctrl: airoha: an7583: add missed features ...
Diffstat (limited to 'Documentation/userspace-api/dcdbas.rst')
-rw-r--r--Documentation/userspace-api/dcdbas.rst99
1 files changed, 99 insertions, 0 deletions
diff --git a/Documentation/userspace-api/dcdbas.rst b/Documentation/userspace-api/dcdbas.rst
new file mode 100644
index 000000000..309cc57a7
--- /dev/null
+++ b/Documentation/userspace-api/dcdbas.rst
@@ -0,0 +1,99 @@
+===================================
+Dell Systems Management Base Driver
+===================================
+
+Overview
+========
+
+The Dell Systems Management Base Driver provides a sysfs interface for
+systems management software such as Dell OpenManage to perform system
+management interrupts and host control actions (system power cycle or
+power off after OS shutdown) on certain Dell systems.
+
+Dell OpenManage requires this driver on the following Dell PowerEdge systems:
+300, 1300, 1400, 400SC, 500SC, 1500SC, 1550, 600SC, 1600SC, 650, 1655MC,
+700, and 750. Other Dell software such as the open source libsmbios project
+is expected to make use of this driver, and it may include the use of this
+driver on other Dell systems.
+
+The Dell libsmbios project aims towards providing access to as much BIOS
+information as possible. See http://linux.dell.com/libsmbios/main/ for
+more information about the libsmbios project.
+
+
+System Management Interrupt
+===========================
+
+On some Dell systems, systems management software must access certain
+management information via a system management interrupt (SMI). The SMI data
+buffer must reside in 32-bit address space, and the physical address of the
+buffer is required for the SMI. The driver maintains the memory required for
+the SMI and provides a way for the application to generate the SMI.
+The driver creates the following sysfs entries for systems management
+software to perform these system management interrupts::
+
+ /sys/devices/platform/dcdbas/smi_data
+ /sys/devices/platform/dcdbas/smi_data_buf_phys_addr
+ /sys/devices/platform/dcdbas/smi_data_buf_size
+ /sys/devices/platform/dcdbas/smi_request
+
+Systems management software must perform the following steps to execute
+a SMI using this driver:
+
+1) Lock smi_data.
+2) Write system management command to smi_data.
+3) Write "1" to smi_request to generate a calling interface SMI or
+ "2" to generate a raw SMI.
+4) Read system management command response from smi_data.
+5) Unlock smi_data.
+
+
+Host Control Action
+===================
+
+Dell OpenManage supports a host control feature that allows the administrator
+to perform a power cycle or power off of the system after the OS has finished
+shutting down. On some Dell systems, this host control feature requires that
+a driver perform a SMI after the OS has finished shutting down.
+
+The driver creates the following sysfs entries for systems management software
+to schedule the driver to perform a power cycle or power off host control
+action after the system has finished shutting down:
+
+/sys/devices/platform/dcdbas/host_control_action
+/sys/devices/platform/dcdbas/host_control_smi_type
+/sys/devices/platform/dcdbas/host_control_on_shutdown
+
+Dell OpenManage performs the following steps to execute a power cycle or
+power off host control action using this driver:
+
+1) Write host control action to be performed to host_control_action.
+2) Write type of SMI that driver needs to perform to host_control_smi_type.
+3) Write "1" to host_control_on_shutdown to enable host control action.
+4) Initiate OS shutdown.
+ (Driver will perform host control SMI when it is notified that the OS
+ has finished shutting down.)
+
+
+Host Control SMI Type
+=====================
+
+The following table shows the value to write to host_control_smi_type to
+perform a power cycle or power off host control action:
+
+=================== =====================
+PowerEdge System Host Control SMI Type
+=================== =====================
+ 300 HC_SMITYPE_TYPE1
+ 1300 HC_SMITYPE_TYPE1
+ 1400 HC_SMITYPE_TYPE2
+ 500SC HC_SMITYPE_TYPE2
+ 1500SC HC_SMITYPE_TYPE2
+ 1550 HC_SMITYPE_TYPE2
+ 600SC HC_SMITYPE_TYPE2
+ 1600SC HC_SMITYPE_TYPE2
+ 650 HC_SMITYPE_TYPE2
+ 1655MC HC_SMITYPE_TYPE2
+ 700 HC_SMITYPE_TYPE3
+ 750 HC_SMITYPE_TYPE3
+=================== =====================