Commit graph

152 commits

Author SHA1 Message Date
Simon Glass
5fd6badbd2 dm: Add a power sequencing uclass
Some devices need special sequences to be used when starting up. Add a
uclass for this. Drivers can be added to provide specific features as
needed.

Signed-off-by: Simon Glass <sjg@chromium.org>
2016-01-21 20:42:34 -07:00
Simon Glass
52db39a22b dm: pinctrl: Add a function to parse PIN_CONFIG flags
Add a function which produces a flags word from a few common PIN_CONFIG
settings. This is useful for simple pinctrl drivers that don't need to worry
about drive strength, etc.

Signed-off-by: Simon Glass <sjg@chromium.org>
2016-01-21 20:42:34 -07:00
Simon Glass
3c97c4fb52 dm: video: test: Add tests for the video uclass
Add tests that check that the video console is working correcty. Also check
that text output produces the expected result. Test coverage includes
character output, wrapping and scrolling.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Anatolij Gustschin <agust@denx.de>
2016-01-20 19:10:16 -07:00
Simon Glass
83510766c9 dm: video: Add a uclass for the text console
The existing LCD/video interface suffers from conflating the bitmap display
with text output on that display. As a result the implementation is more
complex than it needs to me.

We can support multiple text console drivers. Create a separate uclass to
support this, with its own API.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Anatolij Gustschin <agust@denx.de>
2016-01-20 19:10:15 -07:00
Simon Glass
1acafc73bf dm: video: Add a video uclass
U-Boot has separate code for LCDs and 'video' devices. Both now use a
very similar API thanks to earlier work by Nikita Kiryanov. With the driver-
model conversion we should unify these into a single uclass.

Unfortunately there are different features supported by each. This
implementation provides for a common set of features which should serve
most purposes. The intent is to support:

- bitmap devices with 8, 16 and 32 bits per pixel
- text console wih white on black or vice versa
- rotated text console
- bitmap display (BMP format)

More can be added as additional boards are ported over to use driver model
for video.

The name 'video' is chosen for the uclass since it is more generic than LCD.
Another option would be 'display' but that would introduce a third concept
to U-Boot which seems like the wrong approach.

The existing LCD and video init functions are not needed now, so this uclass
makes no attempt to implement them.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Anatolij Gustschin <agust@denx.de>
2016-01-20 19:10:15 -07:00
Vladimir Zapolskiy
f21069ed82 serial: lpc32xx hsuart: port driver to driver model
The change ports NXP LPC32xx 14-clock UART device driver to driver
model.

Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2016-01-13 21:05:22 -05:00
Mugunthan V N
69b41388ba dm: core: Add a new api to get indexed device address
Add new api to get device address based on index.

Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>
Acked-by: Jagan Teki <jteki@openedev.com>
[Rebased on master]
Signed-off-by: Jagan Teki <jteki@openedev.com>
2016-01-13 18:54:22 +05:30
Stefan Roese
66eaea6cd1 dm: core: Add option to configure an offset for the address translation
Some platforms need to ability to configure an offset to the standard
addresses extracted from the device-tree. This patch allows this by
adding a function to DM to configure this offset (if needed).

Signed-off-by: Stefan Roese <sr@denx.de>
Acked-by: Simon Glass <sjg@chromium.org>
Cc: Simon Glass <sjg@chromium.org>
Fixed space before tab:
Signed-off-by: Simon Glass <sjg@chromium.org>
2016-01-12 10:19:09 -07:00
Kamil Lulko
665624149a stm32: Convert serial driver to DM
Signed-off-by: Kamil Lulko <kamil.lulko@gmail.com>
Cc: Simon Glass <sjg@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
2015-12-12 15:56:08 -05:00
Simon Glass
79725ca4f6 Revert "dm: Export device_remove_children / device_unbind_children"
This reverts commit bb52b367f6.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-11-19 20:27:51 -07:00
Simon Glass
7aeac5bc8c dm: core: Add safe device iteration macros
Add iteration macros which support unbinding a device within the loop.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-11-19 20:27:51 -07:00
Simon Glass
34ab37eef5 dm: usb: Add support for USB keyboards with driver model
Switch USB keyboards over to use driver model instead of scanning with the
horrible usb_get_dev_index() function. This involves creating a new uclass
for keyboards, although so far there is no API.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-11-19 20:13:39 -07:00
Thomas Chou
d85879938d dm: implement a MTD uclass
Implement a Memory Technology Device (MTD) uclass. It should
include most flash drivers in the future. Though no uclass ops
are defined yet, the MTD ops could be used.

The NAND flash driver is based on MTD. The CFI flash and SPI
flash support MTD, too. It should make sense to convert them
to MTD uclass.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
2015-11-12 08:26:58 +08:00
Przemyslaw Marczak
5decbf5300 dm: adc: add simple ADC uclass implementation
This commit adds:
- new uclass id: UCLASS_ADC
- new uclass driver: drivers/adc/adc-uclass.c

The new uclass's API allows for ADC operation on:
* single-channel with channel selection by a number
* multti-channel with channel selection by bit mask

ADC uclass's functions:
* single-channel:
  - adc_start_channel()        - start channel conversion
  - adc_channel_data()         - get conversion data
  - adc_channel_single_shot()  - start/get conversion data
* multi-channel:
  - adc_start_channels()       - start selected channels conversion
  - adc_channels_data()        - get conversion data
  - adc_channels_single_shot() - start/get conversion data for channels
                                 selected by bit mask
* general:
  - adc_stop()      - stop the conversion
  - adc_vdd_value() - positive reference Voltage value with polarity [uV]
  - adc_vss_value() - negative reference Voltage value with polarity [uV]
  - adc_data_mask() - conversion data bit mask

The device tree can provide below constraints/properties:
- vdd-polarity-negative: if true: Vdd = vdd-microvolts * (-1)
- vss-polarity-negative: if true: Vss = vss-microvolts * (-1)
- vdd-supply:            phandle to Vdd regulator's node
- vss-supply:            phandle to Vss regulator's node
And optional, checked only if the above corresponding, doesn't exist:
  - vdd-microvolts:      positive reference Voltage [uV]
  - vss-microvolts:      negative reference Voltage [uV]

Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com>
Cc: Simon Glass <sjg@chromium.org>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
2015-11-02 10:38:00 +09:00
Tom Rini
2431492aef Merge git://git.denx.de/u-boot-dm 2015-10-27 19:08:19 -04:00
Simon Glass
8d1f3a9daf dm: core: Tidy up comments in device.h
Correct a few nits found in a recent review. Expand the comments in
dev_get_driver_data() to make it clearer.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-10-23 09:42:28 -06:00
Simon Glass
99b81a4d86 dm: core: Remove a comment about dropping per_child_auto_alloc_size
This has proven useful and we no-longer intend to remove it. Drop the
comment.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-10-23 09:42:28 -06:00
Simon Glass
93c7fe4a0c dm: core: Tidy up devres comments
Adjust the devres comments to be consistent with the rest of the file, and
add one for the struct udevice member. Also rename the 'p' parameter to
'ptr' to avoid single-character names.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-10-23 09:42:28 -06:00
Simon Glass
fb04c9d7b8 dm: core: Fix device flag whitespace
Line up the flag values in the code for easier readability.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-10-23 09:42:28 -06:00
Simon Glass
9a79f6e6d5 dm: core: Adjust device.h header file order
Move a few functions around so that the ordering is consistent.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-10-23 09:42:28 -06:00
Simon Glass
bcbe3d1579 dm: Rename dev_get_parentdata() to dev_get_parent_priv()
The current name is inconsistent with other driver model data access
functions. Rename it and fix up all users.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Joe Hershberger <joe.hershberger@ni.com>
2015-10-23 09:42:28 -06:00
Thomas Chou
4395e06eb9 dm: implement a Miscellaneous uclass
Implement a Miscellaneous uclass with generic read or
write operations. This class is used only for those
do not fit other more general classes.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Acked-by: Simon Glass <sjg@chromium.org>
2015-10-23 07:37:03 +08:00
Thomas Chou
c8a7ba9e6a dm: implement a Timer uclass
Implement a Timer uclass to work with lib/time.c.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Acked-by: Simon Glass <sjg@chromium.org>
2015-10-23 07:37:03 +08:00
Nishanth Menon
ddf56bc7e3 drivers: Introduce a simplified remoteproc framework
Many System on Chip(SoC) solutions are complex with multiple processors
on the same die dedicated to either general purpose of specialized
functions. Many examples do exist in today's SoCs from various vendors.
Typical examples are micro controllers such as an ARM M3/M0 doing a
offload of specific function such as event integration or power
management or controlling camera etc.

Traditionally, the responsibility of loading up such a processor with a
firmware and communication has been with a High Level Operating
System(HLOS) such as Linux. However, there exists classes of products
where Linux would need to expect services from such a processor or the
delay of Linux and operating system being able to load up such a
firmware is unacceptable.

To address these needs, we need some minimal capability to load such a
system and ensure it is started prior to an Operating System(Linux or
any other) is started up.

NOTE: This is NOT meant to be a solve-all solution, instead, it tries to
address certain class of SoCs and products that need such a solution.

A very simple model is introduced here as part of the initial support
that supports microcontrollers with internal memory (no MMU, no
execution from external memory, or specific image format needs). This
basic framework can then (hopefully) be extensible to other complex SoC
processor support as need be.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Nishanth Menon <nm@ti.com>
Acked-by: Simon Glass <sjg@chromium.org>
2015-10-22 14:18:38 -04:00
Bin Meng
1e0f226362 dm: pci: Add an inline API to test if a device is on a PCI bus
Introduce device_is_on_pci_bus() which can be utilized by driver
to test if a device is on a PCI bus.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
2015-09-16 19:53:52 -06:00
Simon Glass
c5acf4a2b3 pinctrl: Add the concept of peripheral IDs
My original pinctrl patch operating using a peripheral ID enum. This was
shared between pinmux and clock and provides an easy way to specify a device
that needs to be controlled, even it is does not (yet) have a driver within
driver model.

Masahiro's new simple pinctrl gets around this by providing a
set_state_simple() pinctrl method. By passing a device to that call the
peripheral ID becomes unnecessary. If the driver needs it, it can calculate
it itself and use it internally.

However this does not solve the problem for peripheral clocks. The 'pure'
solution would be to pass a driver to the clock uclass also. But this
requires that all devices should have a driver, and a struct udevide. Also
a key optimisation of the clock uclass is allowing a peripheral clock to
be set even when there is no device for that clock.

There may be a better way to achive the same goal, but for now it seems
expedient to add in peripheral ID to the pinctrl uclass. Two methods are
added - one to get the peripheral ID and one to select it. The existing
set_state_simple() is effectively the union of these.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-09-02 21:28:22 -06:00
Masahiro Yamada
d90a5a30de pinctrl: add pin control uclass support
This creates a new framework for handling of pin control devices,
i.e. devices that control different aspects of package pins.

This uclass handles pinmuxing and pin configuration; pinmuxing
controls switching among silicon blocks that share certain physical
pins, pin configuration handles electronic properties such as pin-
biasing, load capacitance etc.

This framework can support the same device tree bindings, but if you
do not need full interface support, you can disable some features to
reduce memory foot print.  Typically around 1.5KB is necessary to
include full-featured uclass support on ARM board (CONFIG_PINCTRL +
CONFIG_PINCTRL_FULL + CONFIG_PINCTRL_GENERIC + CONFIG_PINCTRL_PINMUX),
for example.

We are often limited on code size for SPL.  Besides, we still have
many boards that do not support device tree configuration.  The full
pinctrl, which requires OF_CONTROL, does not make sense for those
boards.  So, this framework also has a Do-It-Yourself (let's say
simple pinctrl) interface.  With CONFIG_PINCTRL_FULL disabled, the
uclass itself provides no systematic mechanism for identifying the
peripheral device, applying pinctrl settings, etc.  They must be
done in each low-level driver.  In return, you can save much memory
footprint and it might be useful especially for SPL.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>
2015-08-31 07:57:29 -06:00
Masahiro Yamada
e6cabe4a6d dm: core: allow device_bind() to not return a device pointer
This is useful when we want to bind a device, but do not need the
pointer to the device.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>
2015-08-31 07:57:29 -06:00
Simon Glass
f255d31f90 dm: tpm: Add a uclass for Trusted Platform Modules
Add a new uclass for TPMs which uses almost the same TIS (TPM Interface
Specification) as is currently implemented. Since init() is handled by the
normal driver model probe() method, we don't need to implement that. Also
rename the transfer method to xfer() which is a less clumbsy name.

Once all drivers and users are converted to driver model we can remove the
old code.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Christophe Ricard<christophe-h.ricard@st.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
2015-08-31 07:57:28 -06:00
Masahiro Yamada
71f1e3f19d dm: simplify uclass_foreach_dev() implementation
This can be simply written with list_for_each_entry(), maybe
this macro was not necessary in the first place.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>
2015-08-31 07:56:44 -06:00
Masahiro Yamada
6d99cfaee8 serial: uniphier: drop platform data support
This driver is enabled only for UniPhier SoCs and ARCH_UNIPHIER now
selects OF_CONTROL and SPL_OF_CONTROL.

This driver no longer needs to support platform data configuration.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2015-08-31 00:28:46 +09:00
Masahiro Yamada
0f9258228e of: clean up OF_CONTROL ifdef conditionals
We have flipped CONFIG_SPL_DISABLE_OF_CONTROL.  We have cleansing
devices, $(SPL_) and CONFIG_IS_ENABLED(), so we are ready to clear
away the ugly logic in include/fdtdec.h:

 #ifdef CONFIG_OF_CONTROL
 # if defined(CONFIG_SPL_BUILD) && !defined(SPL_OF_CONTROL)
 #  define OF_CONTROL 0
 # else
 #  define OF_CONTROL 1
 # endif
 #else
 # define OF_CONTROL 0
 #endif

Now CONFIG_IS_ENABLED(OF_CONTROL) is the substitute.  It refers to
CONFIG_OF_CONTROL for U-boot proper and CONFIG_SPL_OF_CONTROL for
SPL.

Also, we no longer have to cancel CONFIG_OF_CONTROL in
include/config_uncmd_spl.h and scripts/Makefile.spl.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
2015-08-18 13:46:05 -04:00
Masahiro Yamada
0a5804b53a dm: drop CONFIG_DM_DEVICE_REMOVE from uncmd list
We do not want to compile the DM remove code for SPL.  Currently,
we undef it in include/config_uncmd_spl.h (for C files) and in
scripts/Makefile.uncmd_spl (for Makefiles).  This is really ugly.

This commit demonstrates how we can deprecate those two files.

Use $(SPL_) for the entry in the Makfile and CONFIG_IS_ENABLED()
in C files.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2015-08-18 13:46:04 -04:00
Simon Glass
74356d7fb1 dm: core: Fix a typo in the uclass_get_device_by_name() comment
This function comment has a typo. Fix it.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2015-08-06 07:44:30 -06:00
Simon Glass
f5c67ea036 dm: core: Add a way to set a device name
Some devices are bound entirely by probing and do not have the benefit of
a device tree to give them a name. This is very common with PCI and USB. In
most cases this is fine, but we should add an official way to set a device
name. This should be called in the device's bind() method.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2015-08-06 07:44:29 -06:00
Masahiro Yamada
40b6f2d020 devres: add debug command to dump device resources
This new command can dump all device resources associated to
each device.  The fields in every line shows:
  - The address of the resource
  - The size of the resource
  - The name of the release function
  - The stage in which the resource has been acquired (BIND/PROBE)

Currently, there is no driver using devres, but if such drivers are
implemented, the output of this command should look like this:

=> dm devres
- root_driver
- soc
- extbus
- serial@54006800
    bfb541e8 (8 byte) devm_kmalloc_release  BIND
    bfb54440 (4 byte) devm_kmalloc_release  PROBE
    bfb54460 (4 byte) devm_kmalloc_release  PROBE
- serial@54006900
    bfb54270 (8 byte) devm_kmalloc_release  BIND
- gpio@55000000
- i2c@58780000
    bfb5bce8 (12 byte) devm_kmalloc_release  PROBE
    bfb5bd10 (4 byte) devm_kmalloc_release  PROBE
- eeprom
    bfb54418 (12 byte) devm_kmalloc_release  BIND

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>
2015-08-06 07:44:29 -06:00
Masahiro Yamada
e2282d7076 devres: make Devres optional with CONFIG_DEVRES
Currently, Devres requires additional 16 byte for each allocation,
which is not so insignificant in some cases.

Add CONFIG_DEVRES to make this framework optional.
If the option is disabled, devres functions fall back to
non-managed variants.  For example, devres_alloc() to kzalloc(),
devm_kmalloc() to kmalloc(), etc.

Because devres_head is also surrounded by an ifdef conditional,
there is no memory overhead when CONFIG_DEVRES is disabled.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Suggested-by: Simon Glass <sjg@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
2015-08-06 07:44:29 -06:00
Masahiro Yamada
2b07f6859a devres: add devm_kmalloc() and friends (managed memory allocators)
devm_kmalloc() is identical to kmalloc() except that the memory
allocated with it is managed and will be automatically released
when the device is removed/unbound.

Likewise for the other variants.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>
2015-08-06 07:44:29 -06:00
Masahiro Yamada
608f26c51b devres: introduce Devres (Managed Device Resource) framework
In U-Boot's driver model, memory is basically allocated and freed
in the core framework.  So, low level drivers generally only have
to specify the size of needed memory with .priv_auto_alloc_size,
.platdata_auto_alloc_size, etc.  Nevertheless, some drivers still
need to allocate/free memory on their own in case they cannot
statically know the necessary memory size.  So, I believe it is
reasonable enough to port Devres into U-boot.

Devres, which originates in Linux, manages device resources for each
device and automatically releases them on driver detach.  With devres,
device resources are guaranteed to be freed whether initialization
fails half-way or the device gets detached.

The basic idea is totally the same to that of Linux, but I tweaked
it a bit so that it fits in U-Boot's driver model.

In U-Boot, drivers are activated in two steps: binding and probing.
Binding puts a driver and a device together.  It is just data
manipulation on the system memory, so nothing has happened on the
hardware device at this moment.  When the device is really used, it
is probed.  Probing initializes the real hardware device to make it
really ready for use.

So, the resources acquired during the probing process must be freed
when the device is removed.  Likewise, what has been allocated in
binding should be released when the device is unbound.  The struct
devres has a member "probe" to remember when the resource was
allocated.

CONFIG_DEBUG_DEVRES is also supported for easier debugging.
If enabled, debug messages are printed each time a resource is
allocated/freed.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>
2015-08-06 07:44:29 -06:00
Masahiro Yamada
aed1a4dd88 dm: add DM_FLAG_BOUND flag
Currently, we only have DM_FLAG_ACTIVATED to indicate the device
status, but we still cannot know in which stage is in progress,
binding or probing.

This commit introduces a new flag, DM_FLAG_BOUND, which is set when
the device is really bound, and cleared when it is unbound.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>
2015-08-06 07:44:29 -06:00
Simon Glass
f33017716e dm: Support address translation for simple-bus
The 'ranges' property can be used to specify a translation from the system
address to the bus address. Add support for this using the dev_get_addr()
function, which devices should use to find their address.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-08-06 07:44:28 -06:00
Simon Glass
801ab9e93c dm: video: Add support for video bridges
A video bridge typically converts video from one format to another, e.g.
DisplayPort to LVDS. Add driver model support for these with a simple
interface to control activation and backlight. The uclass supports GPIO
control of power and reset lines.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-08-05 21:06:13 -06:00
Simon Glass
3d1957f0ea dm: i2c: Add support for multiplexed I2C buses
Add a new I2C_MUX uclass. Devices in this class can multiplex between
several I2C buses, selecting them one at a time for use by the system.
The multiplexing mechanism is left to the driver to decide - it may be
controlled by GPIOs, for example.

The uclass supports only two methods: select() and deselect().

The current mux state is expected to be stored in the mux itself since
it is the only thing that knows how to make things work. The mux can
record the current state and then avoid switching unless it is necessary.
So select() can be skipped if the mux is already in the correct state.
Also deselect() can be made a nop if required.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-08-05 21:06:10 -06:00
Simon Glass
d82ba4c0b4 dm: core: Support finding a device by phandle
It is common for one node to reference another via a phandle. Add support
for obtaining an attached device by this method. As an example, a node may
have a 'power-supply' property which references a regulator, allowing the
driver to turn on its power.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-08-05 20:57:51 -06:00
Simon Glass
3f416f336e dm: Add a return value comment to device_get_child()
At present this function does not specify its return value. Fix it.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2015-08-05 08:42:42 -06:00
Hans de Goede
bb52b367f6 dm: Export device_remove_children / device_unbind_children
These functions are useful to remove all children from an usb bus before
rescanning the bus. Give them a better name and export them.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Simon Glass <sjg@chromium.org>
2015-07-21 17:39:35 -06:00
Simon Glass
97f3ee34b6 dm: Add platform data advice and admonishment
We should guide people more strongly towards device tree to avoid the
proliferation of platform data structures. Add documentation to the driver
model README, and also the platform data header file.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-07-21 17:39:30 -06:00
Simon Glass
f26c8a8e77 dm: Add a clock uclass
Clocks are an important feature of platforms and have become increasing
complex with time. Most modern SoCs have multiple PLLs and dozens of clock
dividers which distribute clocks to on-chip peripherals.

Some SoC implementations have a clock API which is private to that SoC family,
e.g. Tegra and Exynos. This is useful but it would be better to have a
common API that can be understood and used throughout U-Boot.

Add a simple clock API as a starting point. It supports querying and setting
the rate of a clock. Each clock is a device. To reduce memory and processing
overhead the concept of peripheral clocks is provided. These do not need to
be explicit devices - it is possible to write a driver that can adjust the
I2C clock (for example) without an explicit I2C clock device. This can
dramatically reduce the number of devices (and associated overhead) in a
complex SoC.

Clocks are referenced by a number, and it is expected that SoCs will define
that numbering themselves via an enum.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-07-21 17:39:29 -06:00
Simon Glass
f9917454d5 dm: Add a system reset uclass
It is common for system reset to be available at multiple levels in modern
hardware. For example, an SoC may provide a reset option, and a board may
provide its own reset for reasons of security or thoroughness. It is useful
to be able to model this hardware without hard-coding the behaviour in the
SoC or board. Also there is a distinction sometimes between resetting just
the CPU (leaving GPIO state alone) and resetting all the PMICs, just cutting
power.

To achieve this, add a simple system reset uclass. It allows multiple devices
to provide reset functionality and provides a way to walk through them,
requesting a particular reset type until is it provided.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-07-21 17:39:29 -06:00
Simon Glass
6c51df6859 dm: Add support for RAM drivers
Add support for a driver which sets up DRAM and can return information about
the amount of RAM available. This is a first step towards moving RAM init
to driver model.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-07-21 17:39:27 -06:00