A regmap field is an abstraction available in Linux. It provides to access
bitfields in a regmap without having to worry about shifts and masks.

Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>

Some devices need to calculate the regmap base address at runtime. This
makes it impossible to use device tree to get the regmap base. Instead,
allow devices to specify it in the regmap config. This will create a
regmap with a single range that corresponds to the start and size given
by the driver.

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

Right now, the base of a regmap can only be obtained from the device
tree. This makes it impossible for devices which calculate the base at
runtime to use a regmap. An example of such a device is the Cadence
Sierra PHY.

Allow creating a regmap with one range whose start and size can be
specified by the driver based on calculations at runtime.

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

Drivers can configure it to adjust the final read/write location.

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

Right now, regmap_read() and regmap_write() read/write a 32-bit value
only. To write other lengths, regmap_raw_read() and regmap_raw_write()
need to be used.

This means that any driver ported from Linux that relies on
regmap_{read,write}() to know the size already has to be updated at each
callsite. This makes the port harder to maintain.

So, allow specifying the read/write width to make it easier to port the
drivers, since now the only change needed is when initializing the
regmap.

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

Some fields will be introduced in the regmap structure that should be
set to 0 by default. So, once we allocate a regmap, make sure it is
zeroed out to avoid unexpected defaults for those values.

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

Most of new linux drivers are using managed-API to allocate resources. To
ease porting drivers from linux to U-Boot, introduce devm_regmap_init() as
a managed API to get a regmap from the device tree.

Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>

In regmap_raw_{read,write}_range(), offsets are checked to make sure
they aren't out of range. But this check happens _after_ the address is
mapped from physical memory. Input should be sanity-checked before using
it. Mapping the address before validating it leaves the door open to
passing an invalid address to map_physmem(). So check for out of range
offsets _before_ mapping them.

This fixes a segmentation fault in sandbox when -1 is used as an offset
to regmap_{read,write}().

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>

Move this header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>

Free allocated memory in case of an error in regmap_init_mem() and
regmap_init_mem_index().

Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>