Regulators are optional for devices using OPPs and the OPP core
shouldn't be printing any errors for such missing regulators.

It was fine before the commit 0c717d0f, but that failed to update
this part of the code to remove an 'always true' check and an extra
unwanted print message.

Fix that now.

Fixes: 0c717d0f (PM / OPP: Initialize regulator pointer to an error value)
Reported-by: NMarc Gonzalez <marc_gonzalez@sigmadesigns.com>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Stephen pointed out recently, that few structures always confuse him as
they aren't named properly. And this patch tries to address that:

Names are updated as:
- device_opp or dev_opp -> opp_table
- dev_opp_list -> opp_tables
- dev_opp_list_lock -> opp_table_lock
- device_list_opp -> opp_device (it was never a list, but a structure)
- list_dev -> opp_dev
- And similar changes in comments and function names as well.

This also fixes checkpatch warnings that were generated with this patch.

No functional changes.
Suggested-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Some comments were just copy/pasted from other sections and don't match
to the routines they were added for. Fix them.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

We are currently required to do two checks for regulator pointer:
IS_ERR() and IS_NULL().

And multiple instances are reported, about both of these not being used
consistently and so resulting in crashes.

Fix that by initializing regulator pointer with an error value and
checking it only against an error.

This makes code more consistent and more efficient.

Fixes: 7d34d56e (PM / OPP: Disable OPPs that aren't supported by the regulator)
Reported-and-tested-by: NJon Hunter <jonathanh@nvidia.com>
Reported-and-tested-by: NTony Lindgren <tony@atomide.com>
Reported-and-tested-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
[ rjw: Initialize to -ENXIO ]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

We kept u_volt_min/max initialized to 0, when only the target voltage is
present in DT, instead of the target/min/max triplet.

This didn't go well with the regulator framework, as on few calls the
min voltage was set to target and max was set to 0 and so resulted in a
kernel crash like below:

kernel BUG at ../drivers/regulator/core.c:216!

[<c0684af4>] (regulator_check_voltage) from [<c06857ac>] (regulator_set_voltage_unlocked+0x58/0x230)
[<c06857ac>] (regulator_set_voltage_unlocked) from [<c06859ac>] (regulator_set_voltage+0x28/0x54)
[<c06859ac>] (regulator_set_voltage) from [<c0775b28>] (_set_opp_voltage+0x30/0x98)
[<c0775b28>] (_set_opp_voltage) from [<c0776630>] (dev_pm_opp_set_rate+0xf0/0x28c)
[<c0776630>] (dev_pm_opp_set_rate) from [<c096f784>] (__cpufreq_driver_target+0x184/0x2b4)
[<c096f784>] (__cpufreq_driver_target) from [<c0973760>] (dbs_check_cpu+0x1b0/0x1f4)
[<c0973760>] (dbs_check_cpu) from [<c0973f30>] (cpufreq_governor_dbs+0x324/0x5c4)
[<c0973f30>] (cpufreq_governor_dbs) from [<c0970958>] (__cpufreq_governor+0xe4/0x1ec)
[<c0970958>] (__cpufreq_governor) from [<c09711e0>] (cpufreq_init_policy+0x64/0x8c)
[<c09711e0>] (cpufreq_init_policy) from [<c09718cc>] (cpufreq_online+0x2fc/0x708)
[<c09718cc>] (cpufreq_online) from [<c0765ff0>] (subsys_interface_register+0x94/0xd8)
[<c0765ff0>] (subsys_interface_register) from [<c0970530>] (cpufreq_register_driver+0x14c/0x19c)
[<c0970530>] (cpufreq_register_driver) from [<c09746dc>] (dt_cpufreq_probe+0x70/0xec)
[<c09746dc>] (dt_cpufreq_probe) from [<c076907c>] (platform_drv_probe+0x4c/0xb0)
[<c076907c>] (platform_drv_probe) from [<c07678e0>] (driver_probe_device+0x214/0x2c0)
[<c07678e0>] (driver_probe_device) from [<c0767a18>] (__driver_attach+0x8c/0x90)
[<c0767a18>] (__driver_attach) from [<c0765c2c>] (bus_for_each_dev+0x68/0x9c)
[<c0765c2c>] (bus_for_each_dev) from [<c0766d78>] (bus_add_driver+0x1a0/0x218)
[<c0766d78>] (bus_add_driver) from [<c076810c>] (driver_register+0x78/0xf8)
[<c076810c>] (driver_register) from [<c0301d74>] (do_one_initcall+0x90/0x1d8)
[<c0301d74>] (do_one_initcall) from [<c1100e14>] (kernel_init_freeable+0x15c/0x1fc)
[<c1100e14>] (kernel_init_freeable) from [<c0b27a0c>] (kernel_init+0x8/0xf0)
[<c0b27a0c>] (kernel_init) from [<c0307d78>] (ret_from_fork+0x14/0x3c)
Code: e1550004 baffffeb e3a00000 e8bd8070 (e7f001f2)

Fix that by initializing u_volt_min/max to the target voltage in such cases.
Reported-and-tested-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Fixes: 27465902 (PM / OPP: Add support to parse "operating-points-v2" bindings)
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Commit 7d34d56e (PM / OPP: Disable OPPs that aren't supported by
the regulator) causes a crash to happen on Tegra124 Jetson TK1 when
using the DFLL clock source for the CPU.  The DFLL manages the voltage
itself and so there is no regulator specified for the OPPs and so we
get a crash when we try to dereference the regulator pointer.  Fix
this by checking to see if the regulator IS_ERR_OR_NULL before
dereferencing it.

Fixes: 7d34d56e (PM / OPP: Disable OPPs that aren't supported by the regulator)
Signed-off-by: NJon Hunter <jonathanh@nvidia.com>
Reported-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
[ rjw: Changelog ]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This adds a routine, dev_pm_opp_set_rate(), responsible for configuring
power-supply and clock source for an OPP.

The OPP is found by matching against the target_freq passed to the
routine. This shall replace similar code present in most of the OPP
users and help simplify them a lot.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

OPP core has got almost everything now to manage device's OPP
transitions, the only thing left is device's clk. Get that as well.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

V2 bindings have better support for clock-latency and voltage-tolerance
and doesn't need special care. To use callbacks, like
dev_pm_opp_get_max_{transition|volt}_latency(), irrespective of the
bindings, the core needs to know clock-latency/voltage-tolerance for the
earlier bindings.

This patch reads clock-latency/voltage-tolerance from the device node,
irrespective of the bindings (to keep it simple) and use them only for
V1 bindings.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

In few use cases (like: cpufreq), it is desired to get the maximum
latency for changing OPPs. Add support for that.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

In few use cases (like: cpufreq), it is desired to get the maximum
voltage latency for changing OPPs. Add support for that.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Disable any OPPs where the connected regulator isn't able to provide the
specified voltage.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This allows the OPP core to request/free the regulator resource,
attached to a device OPP. The regulator device is fetched using the name
provided by the driver, while calling: dev_pm_opp_set_regulator().

This will work for both OPP-v1 and v2 bindings.

This is a preliminary step for moving the OPP switching logic into the
OPP core.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

sprintf() can access memory outside of the range of the character array,
and is risky in some situations. The driver specified prop_name string
can be longer than NAME_MAX here (only an attacker will do that though)
and so blindly copying it into the character array of size NAME_MAX
isn't safe. Instead we must use snprintf() here.
Reported-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Commit 01fb4d3c ("PM / OPP: Parse 'opp-<prop>-<name>'
bindings") broke support for parsing standard opp-microvolt and
opp-microamp properties.  Fix it by setting 'name' string to
proper value for !prop cases.

Fixes: 01fb4d3c ("PM / OPP: Parse 'opp-<prop>-<name> 'bindings")
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

OPP bindings (for few properties) allow a platform to choose a
value/range among a set of available options. The options are present as
opp-<prop>-<name>, where the platform needs to supply the <name> string.

The OPP properties which allow such an option are: opp-microvolt and
opp-microamp.

Add support to the OPP-core to parse these bindings, by introducing
dev_pm_opp_{set|put}_prop_name() APIs.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Tested-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

OPP bindings allow a platform to enable OPPs based on the version of the
hardware they are used for.

Add support to the OPP-core to parse these bindings, by introducing
dev_pm_opp_{set|put}_supported_hw() APIs.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Tested-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This patch adds debugfs support to OPP layer to export OPPs and their
properties for all the devices.

This creates a top level directory: /sys/kernel/debug/opp and then
device specific directories (based on device names) inside it. For
example: 'cpu0', 'cpu1', etc..

If multiple devices share the OPP table, then the real directory is
created only for the first device. For all others, links are created to
the real directory.

Inside the device specific directory, a separate directory is created
for each OPP. And within that files per opp property.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

_find_device_opp() should be called with rcu-read lock or
dev_opp_list_lock held. Add the opp_rcu_lockdep_assert() check to make
sure caller have taken appropriate locks.

Fix comment over the routine as well.
Suggested-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Writers need to update OPP device and their list with dev_opp_list_lock
mutex held, which was missed at few places. Fix it.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Cc: 4.3 <stable@vger.kernel.org> # 4.3
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

dev_opp_list_lock is used everywhere to protect device and OPP lists,
but dev_pm_opp_set_sharing_cpus() is missed somehow. And instead we used
rcu-lock, which wouldn't help here as we are adding a new list_dev.

This also fixes a problem where we have called kzalloc(..., GFP_KERNEL)
from within rcu-lock, which isn't allowed as kzalloc can sleep when
called with GFP_KERNEL.

With CONFIG_DEBUG_ATOMIC_SLEEP set, we get following lockdep-splat:

include/linux/rcupdate.h:578 Illegal context switch in RCU read-side critical section!

other info that might help us debug this:

rcu_scheduler_active = 1, debug_locks = 0
5 locks held by swapper/0/1:
 #0:  (&dev->mutex){......}, at: [<c02f68f4>] __driver_attach+0x48/0x98
 #1:  (&dev->mutex){......}, at: [<c02f6904>] __driver_attach+0x58/0x98
 #2:  (cpu_hotplug.lock){++++++}, at: [<c00249d0>] get_online_cpus+0x40/0xb0
 #3:  (subsys mutex#5){+.+.+.}, at: [<c02f4f8c>] subsys_interface_register+0x44/0xdc
 #4:  (rcu_read_lock){......}, at: [<c0305c80>] dev_pm_opp_set_sharing_cpus+0x0/0x1e4

stack backtrace:
CPU: 1 PID: 1 Comm: swapper/0 Tainted: G        W       4.3.0-rc7-00047-g81f5932958a8 #59
Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
[<c0016874>] (unwind_backtrace) from [<c001355c>] (show_stack+0x10/0x14)
[<c001355c>] (show_stack) from [<c022553c>] (dump_stack+0x94/0xbc)
[<c022553c>] (dump_stack) from [<c004904c>] (___might_sleep+0x24c/0x298)
[<c004904c>] (___might_sleep) from [<c00f07e4>] (kmem_cache_alloc+0xe8/0x164)
[<c00f07e4>] (kmem_cache_alloc) from [<c0305354>] (_add_list_dev+0x30/0x58)
[<c0305354>] (_add_list_dev) from [<c0305d50>] (dev_pm_opp_set_sharing_cpus+0xd0/0x1e4)
[<c0305d50>] (dev_pm_opp_set_sharing_cpus) from [<c040eda4>] (cpufreq_init+0x4cc/0x62c)
[<c040eda4>] (cpufreq_init) from [<c040a964>] (cpufreq_online+0xbc/0x73c)
[<c040a964>] (cpufreq_online) from [<c02f4fe0>] (subsys_interface_register+0x98/0xdc)
[<c02f4fe0>] (subsys_interface_register) from [<c040a640>] (cpufreq_register_driver+0x110/0x17c)
[<c040a640>] (cpufreq_register_driver) from [<c040ef64>] (dt_cpufreq_probe+0x60/0x8c)
[<c040ef64>] (dt_cpufreq_probe) from [<c02f8084>] (platform_drv_probe+0x44/0xa4)
[<c02f8084>] (platform_drv_probe) from [<c02f67c0>] (driver_probe_device+0x208/0x2f4)
[<c02f67c0>] (driver_probe_device) from [<c02f6940>] (__driver_attach+0x94/0x98)
[<c02f6940>] (__driver_attach) from [<c02f4c1c>] (bus_for_each_dev+0x68/0x9c)
Reported-by: NMichael Turquette <mturquette@baylibre.com>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Cc: 4.3 <stable@vger.kernel.org> # 4.3
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Move all DT parsing for the power supplies to a single function, rather
than keeping them at separate places. This will help manage things
properly.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Clearly distinguish routines based on what version of bindings they
parse. We have already postfixed routines properly with _v2 for new
bindings. Postfix the older ones now with _v1.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

To identify OPP core's print messages easily, prefix them with
KBUILD_MODNAME.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Move cpu device specific code out of generic opp library, and add it to
cpu.c.

Along with that, create a core-internal opp.h header, which will be used
to share structures and function prototypes within opp core.
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

OPP code is expanding and is already present in multiple directories
(cpufreq and power). Lets move it to its own directory, to manage it
better.

This also moves/renames the cpufreq_opp file to cpu.c, as it will
contain helpers for cpu device. Its not just about cpufreq, other
frameworks can use OPPs as well.
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

That's the naming convention followed in most of opp core, but few
routines didn't follow this, fix them.
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NShawn Guo <shawnguo@kernel.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

free-table routines are opposite of init-table ones, and must be named
to make that clear. Opposite of 'init' is 'exit', but those doesn't suit
really well.

Replace 'init' with 'add' and 'free' with 'remove'.
Reported-by: NPavel Machek <pavel@ucw.cz>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NShawn Guo <shawnguo@kernel.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

We already have a better API to get the opp descriptor block's node from
cpu-node. Lets reuse that instead of creating our own routines for the
same stuff. That cleans the code a lot.

This also kills a check we had earlier (as we are using the generic API
now). Earlier we used to check if the operating-points-v2 property
contained multiple phandles instead of a single phandle.

Killing this check isn't an issue because, we only parse the first entry
with of_parse_phandle(). So, if a user passes multiple phandles, its
really his problem :)
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

There is no point returning suspend_opp, if it is disabled by the core.
As we can't use it at all. Fix it.

Fixes: 4eafbd15 ("PM / OPP: add dev_pm_opp_get_suspend_opp() helper")
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Add dev_pm_opp_get_suspend_opp() helper to obtain suspend opp.
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

IS_ERR(_OR_NULL) already contain an 'unlikely' compiler flag and there
is no need to do that again from its callers. Drop it.
Acked-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Dan Carpenter reported (generated with static checker):

drivers/base/power/opp.c:949 _opp_add_static_v2()
warn: passing casted pointer '&new_opp->clock_latency_ns' to
'of_property_read_u32()' 64 vs 32.

This code will break on 64 bit, big endian machines.

Fix this by reading the value in a u32 type variable first and then
assigning it to the unsigned long variable.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Suggested-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

_of_init_opp_table_v2() isn't freeing up resources on some errors and
the error values returned are also not correct always.

This fixes following problems:
- Return -ENOENT, if no entries are found in the table.
- Use IS_ERR() to properly check return value of _find_device_opp().
- Return error value with PTR_ERR() in above case.
- Free table if _find_device_opp() fails.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Add dev_pm_opp_is_turbo() helper to verify if an opp is to be used only
for turbo mode or not.
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

With "operating-points-v2" its possible to tell which devices share
OPPs. We already have infrastructure to decode that information.

This patch adds following APIs:
 - of_get_cpus_sharing_opps: Returns cpumask of CPUs sharing OPPs (only
   valid with v2 bindings).
 - of_cpumask_init_opp_table: Initializes OPPs for all CPUs present in
   cpumask.
 - of_cpumask_free_opp_table: Frees OPPs for all CPUs present in cpumask.

 - set_cpus_sharing_opps: Sets which CPUs share OPPs (only valid with old
   OPP bindings, as this information isn't present in DT).
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Reviewed-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

With "operating-points-v2" bindings, it's possible to specify the OPP to
which the device must be switched, before suspending.

This patch adds support for getting that information.
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Reviewed-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

An opp can be shared by multiple devices, for example its very common
for CPUs to share the OPPs, i.e. when they share clock/voltage rails.

This patch adds support of shared OPPs to the OPP library.

Instead of a single device, dev_opp will now contain a list of devices
that use it. It also senses if the device (we are trying to initialize
OPPs for) shares OPPs with a device added earlier and in that case we
update the list of devices managed by OPPs instead of duplicating OPPs
again.

The same infrastructure will be used for the old OPP bindings, with
later patches.
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Reviewed-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

With "operating-points-v2" bindings, clock-latency is defined per OPP.
Users of this value expect a single value which defines the latency to
switch to any clock rate. Find maximum clock-latency-ns from the OPP
table to service requests from such users.
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Reviewed-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This adds support in OPP library to parse and create list of OPPs from
operating-points-v2 bindings. It takes care of most of the properties of
new bindings (except shared-opp, which will be handled separately).

For backward compatibility, we keep supporting earlier bindings. We try
to search for the new bindings first, in case they aren't present we
look for the old deprecated ones.

There are few things marked as TODO:
- Support for multiple OPP tables
- Support for multiple regulators

They should be fixed separately.
Reviewed-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>