Commit graph

21 commits

Author SHA1 Message Date
Simon Glass
4dc5259ac7 dm: gpio: Allow the uclass to work without printf()
For SPL we don't really need sprintf() and with tiny-printf this is not
available. Allow this to be dropped in SPL when using tiny-printf.

Signed-off-by: Simon Glass <sjg@chromium.org>
2016-01-20 19:06:22 -07:00
Simon Glass
eca4866586 dm: gpio: Check a GPIO is valid before using it
Since a gpio_desc is allowed to be invalid we should return an error
indicating that the operation cannot be completed. This can happen if the
GPIO is optional - e.g. some devices may have a reset line and some may
not.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-08-05 21:06:14 -06:00
Simon Glass
efa677fb48 dm: gpio: Add dm_gpio_request() to manually request a GPIO
This function can be used for testing to manually request a GPIO for use,
without resorting to the legacy GPIO API.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-07-21 17:39:23 -06:00
Simon Glass
32ec159844 dm: gpio: Add dm_gpio_lookup_name() to look up a GPIO name
Provide a driver-model function to look up a GPIO name. Make the standard
function use it.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-07-21 17:39:23 -06:00
Bhuvanchandra DV
ae89bb0d36 dm: gpio: uclass: Add flag to control sequence numbering
Like SPI and I2C few GPIO controllers also have
multiple chip instances. This patch adds the
flag 'DM_UC_FLAG_SEQ_ALIAS' in gpio_uclass driver
to control device sequence numbering. By defalut
the dev->r_seq for gpio_uclass will alwalys
returns -1, which leads the gpio driver probe
failure when using the driver with device trees.

Signed-off-by: Bhuvanchandra DV <bhuvanchandra.dv@toradex.com>
2015-06-08 08:41:54 +02:00
Simon Glass
962f5caf60 dm: gpio: Add error handling and a function to claim vector GPIOs
gpio_get_values_as_int() should return an error if something goes wrong.
Also provide gpio_claim_vector(), a function to request the GPIOs and set
them to input mode. Otherwise callers have to do this themselves.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>
2015-05-13 09:24:06 -07:00
Simon Glass
56a71f891b dm: gpio: Add an implementation for gpio_get_number()
This has a prototype but no implementation. It returns the global GPIO number
given a gpio_desc. It is useful for debugging in some cases.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Marek Vasut <marex@denx.de>
2015-04-18 11:11:19 -06:00
Przemyslaw Marczak
2984e7a102 dm: gpio: request list: return the count if requests max_count reached
The function gpio_request_list_by_name_nodev() returned -ENOSPC error,
when the loop count was greater than requested count. This was wrong,
because function should return the requested gpio count, when meets
the call request without errors. Now, the loop ends on requested
max_count.

Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com>
Acked-by: Simon Glass <sjg@chromium.org>
2015-04-18 11:11:17 -06:00
Simon Glass
e564f054af dm: core: Add dev_get_uclass_priv() to access uclass private data
Add a convenience function to access the private data that a uclass stores
for each of its devices. Convert over most existing uses for consistency
and to provide an example for others.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-04-16 19:27:42 -06:00
Simon Glass
3669e0e759 dm: gpio: Add better functions to request GPIOs
At present U-Boot sort-of supports the standard way of reading GPIOs from
device tree nodes, but the support is incomplete, a bit clunky and only
works for GPIO bindings where #gpio-cells is 2.

Add new functions to request GPIOs, taking full account of the device
tree binding. These permit requesting a GPIO with a simple call like:

   gpio_request_by_name(dev, "cd-gpios", 0, &desc, GPIOD_IS_IN);

This will request the GPIO, looking at the device's node which might be
this, for example:

   cd-gpios = <&gpio TEGRA_GPIO(B, 3) GPIO_ACTIVE_LOW>;

The GPIO will be set to input mode in this case and polarity will be
honoured by the GPIO calls.

It is also possible to request and free a list of GPIOs.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-01-29 17:09:51 -07:00
Simon Glass
0dac4d51f5 dm: gpio: Add a driver GPIO translation method
Only the GPIO driver knows about the full GPIO device tree binding used by
a device. Add a method to allow the driver to provide this information to the
uclass, including the GPIO offset within the device and flags such as the
polarity.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-01-29 17:09:50 -07:00
Simon Glass
ae7123f876 dm: gpio: Add a native driver model API
So far driver model's GPIO uclass just implements the existing GPIO API.
This has some limitations:

- it requires manual device tree munging to support GPIOs in device tree
    (fdtdec_get_gpio() and friends)
- it does not understand polarity
- it is somewhat slower since we must scan for the GPIO device each time
- Global GPIO numbering can change if other GPIO drivers are probed
- it requires extra steps to set the GPIO direction and value

The new functions have a dm_ prefix where necessary to avoid name conflicts
but we can remove that when it is no-longer needed. The new struct gpio_desc
holds all required information about the GPIO. For now this is intended to
be stored by the client requesting the GPIO, but in future it might be
brought into the uclass in some way.

With these changes the old GPIO API still works, and uses the driver model
API underneath.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-01-29 17:09:50 -07:00
Simon Glass
e5901c94e3 dm: gpio: Add a function to read an ID from a list of GPIOs
For board IDs a common approach is to set aside several GPIOs for use in
determining the board ID. This can provide information about board features
and the revision.

Add a function that turns a list of GPIOs into an integer by assigning
each GPIO to a single bit.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-11-21 07:24:11 +01:00
Simon Glass
d44f597b12 dm: gpio: Add gpio_requestf() helper for printf() strings
Add a helper which permits a printf()-style format string for the requester
string.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-10-23 19:29:52 -06:00
Simon Glass
0757535a7e dm: Move the function for getting GPIO status into the uclass
This function can be more easily tested if it is in the uclass.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-10-23 19:29:52 -06:00
Simon Glass
6449a506d6 dm: gpio: Add gpio_get_function() and friends
Add helpers to the uclass to allow finding out the pin function.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-10-23 19:29:52 -06:00
Simon Glass
b892d127ff dm: gpio: Implement GPIO reservation in the uclass
We have several GPIO drivers now and all are doing similar things to record
which GPIOs are reserved.

Move this logic into the uclass to make the drivers similar.

We retain the request()/free() methods since currently one driver does use
these for setting up the pin.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-10-23 19:29:51 -06:00
Simon Glass
fe1ef50338 dm: gpio: Support numbered GPIOs
At present banks must be named and it is not possible to refer to GPIOs by
number in driver model. Some boards use numbering - e.g. OMAP. It is fairly
easy to support by detecting the absense of a bank name (which starts with
a letter).

Add support for numbered GPIOs in addition to the existing bank support.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@ti.com>
2014-10-23 19:29:07 -06:00
Simon Glass
939cda5bf0 dm: Use case-insensitive comparison for GPIO banks
We want 'N0' and 'n0' to mean the same thing, so ensure that case is not
considered when naming GPIO banks.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-06-20 11:55:39 -06:00
Heiko Schocher
54c5d08a09 dm: rename device struct to udevice
using UBI and DM together leads in compiler error, as
both define a "struct device", so rename "struct device"
in include/dm/device.h to "struct udevice", as we use
linux code (MTD/UBI/UBIFS some USB code,...) and cannot
change the linux "struct device"

Signed-off-by: Heiko Schocher <hs@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Cc: Marek Vasut <marex@denx.de>
2014-05-27 10:21:32 -04:00
Simon Glass
96495d90fe dm: Add GPIO support and tests
Add driver model support for GPIOs. Since existing GPIO drivers do not use
driver model, this feature must be enabled by CONFIG_DM_GPIO. After all
GPO drivers are converted over we can perhaps remove this config.

Tests are provided for the sandbox implementation, and are a sufficient
sanity check for basic operation.

The GPIO uclass understands the concept of named banks of GPIOs, with each
GPIO device providing a single bank. Within each bank the GPIOs are numbered
using an offset from 0 to n-1. For example a bank named 'b' with 20
offsets will provide GPIOs named b0 to b19.

Anonymous GPIO banks are also supported, and are just numbered without any
prefix.

Each time a GPIO driver is added to the uclass, the GPIOs are renumbered
accordinging, so there is always a global GPIO numbering order.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Pavel Herrmann <morpheus.ibis@gmail.com>
Signed-off-by: Viktor Křivák <viktor.krivak@gmail.com>
Signed-off-by: Tomas Hlavacek <tmshlvck@gmail.com>
2014-03-04 12:15:30 -05:00