Hi Przemyslaw, On 20 April 2015 at 12:07, Przemyslaw Marczak <p.marc...@samsung.com> wrote: > Since this framework is still under the construction, the main > documentation is kept in the header files. > > Signed-off-by: Przemyslaw Marczak <p.marc...@samsung.com> > --- > Changes v2, V3: > - update documentation with the framework api changes > - remove doc file name 'dm' prefix > > Changes V4: > - move the description to the headers and leave only general info > > --- > doc/driver-model/pmic-framework.txt | 142 > ++++++++++++++++++++++++++++++++++++ > 1 file changed, 142 insertions(+) > create mode 100644 doc/driver-model/pmic-framework.txt
Acked-by: Simon Glass <s...@chromium.org> > > diff --git a/doc/driver-model/pmic-framework.txt > b/doc/driver-model/pmic-framework.txt > new file mode 100644 > index 0000000..cc82236 > --- /dev/null > +++ b/doc/driver-model/pmic-framework.txt > @@ -0,0 +1,142 @@ > +# > +# (C) Copyright 2014-2015 Samsung Electronics > +# Przemyslaw Marczak <p.marc...@samsung.com> > +# > +# SPDX-License-Identifier: GPL-2.0+ > +# > + > +PMIC framework based on Driver Model > +==================================== > +TOC: > +1. Introduction > +2. How does it work > +3. Pmic uclass > +4. Regulator uclass > + > +1. Introduction > +=============== > +This is an introduction to driver-model multi uclass PMIC IC's support. > +At present it's based on two uclass types: > +- UCLASS_PMIC - basic uclass type for PMIC I/O, which provides common > + read/write interface. > +- UCLASS_REGULATOR - additional uclass type for specific PMIC features, > + which are Voltage/Current regulators. > + > +New files: > +UCLASS_PMIC: > +- drivers/power/pmic/pmic-uclass.c > +- include/power/pmic.h > +UCLASS_REGULATOR: > +- drivers/power/regulator/regulator-uclass.c > +- include/power/regulator.h > + > +Commands: > +- common/cmd_pmic.c > +- common/cmd_regulator.c > + > +2. How doees it work > +==================== > +The Power Management Integrated Circuits (PMIC) are used in embedded systems > +to provide stable, precise and specific voltage power source with > over-voltage > +and thermal protection circuits. > + > +The single PMIC can provide various functions by single or multiple > interfaces, > +like in the example below. > + > +-- SoC > + | > + | ______________________________________ > + | BUS 0 | Multi interface PMIC IC |--> LDO out 1 > + | e.g.I2C0 | |--> LDO out N > + |-----------|---- PMIC device 0 (READ/WRITE ops) | > + | or SPI0 | |_ REGULATOR device (ldo/... ops) |--> BUCK out 1 > + | | |_ CHARGER device (charger ops) |--> BUCK out M > + | | |_ MUIC device (microUSB con ops) | > + | BUS 1 | |_ ... |---> BATTERY > + | e.g.I2C1 | | > + |-----------|---- PMIC device 1 (READ/WRITE ops) |---> USB in 1 > + . or SPI1 | |_ RTC device (rtc ops) |---> USB in 2 > + . |______________________________________|---> USB out > + . > + > +Since U-Boot provides driver model features for I2C and SPI bus drivers, > +the PMIC devices should also support this. By the pmic and regulator API's, > +PMIC drivers can simply provide a common functions, for multi-interface and > +and multi-instance device support. > + > +Basic design assumptions: > + > +- Common I/O API - UCLASS_PMIC > +For the multi-function PMIC devices, this can be used as parent I/O device > +for each IC's interface. Then, each children uses the same dev for > read/write. > + > +- Common regulator API - UCLASS_REGULATOR > +For driving the regulator attributes, auto setting function or command line > +interface, based on kernel-style regulator device tree constraints. > + > +For simple implementations, regulator drivers are not required, so the code > can > +use pmic read/write directly. > + > +3. Pmic uclass > +============== > +The basic informations: > +* Uclass: 'UCLASS_PMIC' > +* Header: 'include/power/pmic.h' > +* Core: 'drivers/power/pmic/pmic-uclass.c' > + config: 'CONFIG_DM_PMIC' > +* Command: 'common/cmd_pmic.c' > + config: 'CONFIG_CMD_PMIC' > +* Example: 'drivers/power/pmic/max77686.c' > + > +This is still under the construction. So for the API description, please > refer > +to the header file. > + > +As an example of the pmic driver, please refer to the MAX77686 driver. > + > +Please pay attention for the driver's '.bind' method. Exactly the function > call: I think 'driver's bind() method' is better than a quoted '.bind'. > +'pmic_bind_childs()', which is used to bind the regulators by using the > array of > +regulator's node, compatible prefixes. > + > +The 'pmic; command also supports the new API. So the pmic command can be > enabled > +by adding CONFIG_CMD_PMIC. > +The new pmic command allows to: > +- list pmic devices > +- choose the current device (like the mmc command) > +- read or write the pmic register > +- dump all pmic registers > + > +This command can use only UCLASS_PMIC devices, since this uclass is designed > +for pmic I/O operations only. > + > +For more informations, please refer to the file: 'common/cmd_pmic.c'. information > + > +4. Regulator uclass > +=================== > +The basic informations: information > +* Uclass: 'UCLASS_REGULATOR' > +* Header: 'include/power/regulator.h' > +* Core: 'drivers/power/regulator/regulator-uclass.c' > + config: 'CONFIG_DM_REGULATOR' > + binding: 'doc/device-tree-bindings/regulator/regulator.txt' > +* Command: 'common/cmd_regulator.c' > + config: 'CONFIG_CMD_REGULATOR' > +* Example: 'drivers/power/regulator/max77686.c' > + 'drivers/power/pmic/max77686.c' (required I/O driver for the > above) > +* Example: 'drivers/power/regulator/fixed.c' > + config" 'CONFIG_DM_REGULATOR_FIXED' > + > +This is still under the construction. So for the API description, please > refer > +to the header file. What is still under construction? > + > +For the example regulator driver, please refer to the MAX77686 regulator > driver, > +but this driver can't operate without pmic's example driver, which provides > an > +I/O interface for MAX77686 regulator. > + > +The second example is a fixed Voltage/Current regulator for a common use. > + > +The 'regulator' command also supports the new API. The command allow: allows, or maybe s/allow/allows you to/ > +- list regulator devices > +- choose the current device (like the mmc command) > +- do all regulator-specific operations > + > +For more informations, please refer to the file: 'common/cmd_regulator.c' > -- > 1.9.1 > Regards, Simon _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
