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authorJulien Panis <jpanis@baylibre.com>2023-05-11 11:51:25 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2023-06-15 13:41:53 +0200
commitdce548889650c188a1078064d038fb72f3fd1c11 (patch)
tree7159bb4c5efd3a1a0ad8d0157e507dde17905ff9
parenta0df3ef087f8aaebbdf205b1b2e126ec9ef6b113 (diff)
Documentation: Add TI TPS6594 PFSM
This patch adds documentation for the TPS6594 PFSM driver. The PFSM controls the operational states of the TPS6594 PMIC. Depending on the operational mode, some power domain networks remain energized while others can be off. Signed-off-by: Julien Panis <jpanis@baylibre.com> Message-ID: <20230511095126.105104-6-jpanis@baylibre.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--Documentation/misc-devices/index.rst1
-rw-r--r--Documentation/misc-devices/tps6594-pfsm.rst87
-rw-r--r--Documentation/userspace-api/ioctl/ioctl-number.rst1
3 files changed, 89 insertions, 0 deletions
diff --git a/Documentation/misc-devices/index.rst b/Documentation/misc-devices/index.rst
index 756be15a49a4..ecc40fbbcfb8 100644
--- a/Documentation/misc-devices/index.rst
+++ b/Documentation/misc-devices/index.rst
@@ -28,5 +28,6 @@ fit into other categories.
oxsemi-tornado
pci-endpoint-test
spear-pcie-gadget
+ tps6594-pfsm
uacce
xilinx_sdfec
diff --git a/Documentation/misc-devices/tps6594-pfsm.rst b/Documentation/misc-devices/tps6594-pfsm.rst
new file mode 100644
index 000000000000..4ada37ccdcba
--- /dev/null
+++ b/Documentation/misc-devices/tps6594-pfsm.rst
@@ -0,0 +1,87 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+=====================================
+Texas Instruments TPS6594 PFSM driver
+=====================================
+
+Author: Julien Panis (jpanis@baylibre.com)
+
+Overview
+========
+
+Strictly speaking, PFSM (Pre-configurable Finite State Machine) is not
+hardware. It is a piece of code.
+
+The TPS6594 PMIC (Power Management IC) integrates a state machine which
+manages operational modes. Depending on the current operational mode,
+some voltage domains remain energized while others can be off.
+
+The PFSM driver can be used to trigger transitions between configured
+states. It also provides R/W access to the device registers.
+
+Supported chips
+---------------
+
+- tps6594-q1
+- tps6593-q1
+- lp8764-q1
+
+Driver location
+===============
+
+drivers/misc/tps6594-pfsm.c
+
+Driver type definitions
+=======================
+
+include/uapi/linux/tps6594_pfsm.h
+
+Driver IOCTLs
+=============
+
+:c:macro::`PMIC_GOTO_STANDBY`
+All device resources are powered down. The processor is off, and
+no voltage domains are energized.
+
+:c:macro::`PMIC_GOTO_LP_STANDBY`
+The digital and analog functions of the PMIC, which are not
+required to be always-on, are turned off (low-power).
+
+:c:macro::`PMIC_UPDATE_PGM`
+Triggers a firmware update.
+
+:c:macro::`PMIC_SET_ACTIVE_STATE`
+One of the operational modes.
+The PMICs are fully functional and supply power to all PDN loads.
+All voltage domains are energized in both MCU and Main processor
+sections.
+
+:c:macro::`PMIC_SET_MCU_ONLY_STATE`
+One of the operational modes.
+Only the power resources assigned to the MCU Safety Island are on.
+
+:c:macro::`PMIC_SET_RETENTION_STATE`
+One of the operational modes.
+Depending on the triggers set, some DDR/GPIO voltage domains can
+remain energized, while all other domains are off to minimize
+total system power.
+
+Driver usage
+============
+
+See available PFSMs::
+
+ # ls /dev/pfsm*
+
+Dump the registers of pages 0 and 1::
+
+ # hexdump -C /dev/pfsm-0-0x48
+
+See PFSM events::
+
+ # cat /proc/interrupts
+
+Userspace code example
+----------------------
+
+samples/pfsm/pfsm-wakeup.c
diff --git a/Documentation/userspace-api/ioctl/ioctl-number.rst b/Documentation/userspace-api/ioctl/ioctl-number.rst
index 4f7b23faebb9..4ea5b837399a 100644
--- a/Documentation/userspace-api/ioctl/ioctl-number.rst
+++ b/Documentation/userspace-api/ioctl/ioctl-number.rst
@@ -180,6 +180,7 @@ Code Seq# Include File Comments
'P' 00-0F drivers/usb/class/usblp.c conflict!
'P' 01-09 drivers/misc/pci_endpoint_test.c conflict!
'P' 00-0F xen/privcmd.h conflict!
+'P' 00-05 linux/tps6594_pfsm.h conflict!
'Q' all linux/soundcard.h
'R' 00-1F linux/random.h conflict!
'R' 01 linux/rfkill.h conflict!