PM / OPP: Introduce APIs to transition OPPs

Hi Guys,

This patchset add APIs in OPP layer to allow OPPs transitioning from within OPP layer. Currently all OPP users need to replicate the same code to switch between OPPs. While the same can be handled easily by OPP-core.

The first 7 patches update the OPP core to introduce the new APIs and the next Nine patches update cpufreq-dt for the same.

11 out of 17 are already Reviewed by Stephen, only few are left :)

I hope this is the last version of the series :)

Testing:
- Tested on exynos 5250-arndale (dual-cortex-A15)
- Tested for both Old-V1 bindings and New V2 bindings
- Tested with regulator names as: 'cpu-supply' and 'cpu0-supply'
- Tested with Unsupported supply ranges as well, to check the opp-disable logic

V2->V3:
- Very minor updates.
- find_supply_name() doesn't return an error value now, and so its callers don't check for it.
- And so we don't need to initialize name to NULL

Viresh Kumar (16):
PM / OPP: get/put regulators from OPP core
PM / OPP: Disable OPPs that aren't supported by the regulator PM / OPP: Introduce dev_pm_opp_get_max_volt_latency()
PM / OPP: Introduce dev_pm_opp_get_max_transition_latency() PM / OPP: Parse clock-latency and voltage-tolerance for v1 bindings PM / OPP: Manage device clk
PM / OPP: Add dev_pm_opp_set_rate()
cpufreq: dt: Convert few pr_debug/err() calls to dev_dbg/err()
cpufreq: dt: Rename 'need_update' to 'opp_v1'
cpufreq: dt: OPP layers handles clock-latency for V1 bindings as well
cpufreq: dt: Pass regulator name to the OPP core
cpufreq: dt: Unsupported OPPs are already disabled
cpufreq: dt: Reuse dev_pm_opp_get_max_transition_latency()
cpufreq: dt: Use dev_pm_opp_set_rate() to switch frequency
cpufreq: dt: No need to fetch voltage-tolerance
cpufreq: dt: No need to allocate resources anymore

 drivers/base/power/opp/core.c | 420 ++++++++++++++++++++++++++++++++++++++++++
 drivers/base/power/opp/opp.h  |  13 ++
 drivers/cpufreq/cpufreq-dt.c  | 300 +++++++++++-------------------
 include/linux/pm_opp.h        |  27 +++
 4 files changed, 565 insertions(+), 195 deletions(-)

2.7.1.370.gb2aa7f8