clk: mvebu: fix spelling mistake "gatable" -> "gateable"

There are a few spelling mistakes in comments and a pr_err
error message. Fix these.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: mvebu: use SPDX-License-Identifier

Convert the remaining files to SPDX license description.

Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: mvebu: Use kcalloc() in two functions

* Multiplications for the size determination of memory allocations
indicated that array data structures should be processed.
Thus use the corresponding function "kcalloc".

This issue was detected by using the Coccinelle software.

* Replace the specification of data types by pointer dereferences
to make the corresponding size determination a bit safer according to
the Linux coding style convention.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: mvebu: Remove CLK_IS_ROOT

This flag is a no-op now. Remove usage of the flag.

Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: move the common clock's to_clk_*(_hw) macros to clk-provider.h

to_clk_*(_hw) macros have been repeatedly defined in many places.
This patch moves all the to_clk_*(_hw) definitions in the common
clock framework to public header clk-provider.h, and drop the local
definitions.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: Remove unneeded semicolons

There are cleary typo errors so can be removed.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: mvebu: Remove clk.h include

Clock provider drivers generally shouldn't include clk.h because
it's the consumer API. Only include the header if necessary. The
clkdev.h include isn't used here either, so drop it and add in
slab.h to keep things compiling.

Cc: Boris Brezillon <boris.brezillon@free-electrons.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Gregory CLEMENT <gregory.clement@free-electrons.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: mvebu: extend common code to allow an optional refclk

The Armada 39x, contrary to its predecessor, has a configurable
reference clock frequency, of either 25 Mhz, or 40 Mhz. For the
previous SoCs, it was fixed to 25 Mhz and described directly as such
in the Device Tree.

For Armada 39x, we need to read certain registers to know whether the
frequency is 25 or 40 Mhz. Therefore, this commit extends the common
mvebu clock code to allow the SoC-specific code to say it wants to
register a reference clock, by giving a non-NULL ->get_refclk_freq()
function pointer in its coreclk_soc_desc structure.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>

clk: mvebu: add suspend/resume for gatable clocks

This commit adds suspend/resume support for the gatable clock driver
used on Marvell EBU platforms. When getting out of suspend, the
Marvell EBU platforms go through the bootloader, which re-enables all
gatable clocks. However, upon resume, the clock framework will not
disable again all gatable clocks that are not used.

Therefore, if the clock driver does not save/restore the state of the
gatable clocks, all gatable clocks that are not claimed by any device
driver will remain enabled after a resume. This is why this driver
saves and restores the state of those clocks.

Since clocks aren't real devices, we don't have the normal ->suspend()
and ->resume() of the device model, and have to use the ->suspend()
and ->resume() hooks of the syscore_ops mechanism. This mechanism has
the unfortunate idea of not providing a way of passing private data,
which requires us to change the driver to make the assumption that
there is only once instance of the gatable clock control structure.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: linux-kernel@vger.kernel.org
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Link: https://lkml.kernel.org/r/1416585613-2113-9-git-send-email-thomas.petazzoni@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

clk: mvebu: fix sscg node lookup

Commit 15917b16022427c53755abff4dc7051f3076dd7a ("clk: mvebu: Fix clk
frequency value if SSCG is enabled") introduced some logic in the
common mvebu clock code to adjust the clock frequency according to the
configuration of the SSCG.

In order to do this, it looks up for a DT node called "sscg" and maps
it before accessing the SSCG configuration register.

However, the lookup is currently done using:

sscg_np = of_find_node_by_name(np, "sscg");

where "np" is a pointer to the DT node of the clock for which we are
calculating the adjusted frequency. This means that if the "sscg" node
is *after* the clock node in the Device Tree, it works fine (and
that's the case for Armada 370).

However, if it turns out that the "sscg" node is *before* the clock
node in the Device Tree, it won't work because the sscg node will not
be found.

What we really want here is a search of the entire Device Tree, not
only starting from the clock node, so instead of passing "np" as first
argument of of_find_node_by_name(), we simply need to pass
NULL. Passing a non-NULL argument is typically used in a loop, so that
the search for the next matching node starts right after the node that
was matched.

This makes the "np" argument to the kirkwood_fix_sscg_deviation()
function unnecessary, which leads to further cleanups.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Fixes: 15917b1602242 ("clk: mvebu: Fix clk frequency value if SSCG is enabled")
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Link: https://lkml.kernel.org/r/1410880503-2322-1-git-send-email-thomas.petazzoni@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

clk: mvebu: Fix clk frequency value if SSCG is enabled

When the SSCG (Spread Spectrum Clock Generator) is enabled, it shifts
the frequency of the clock. The percentage is no more than 1% but when
the clock is used for a timer it leads to a clock drift.

This patch allows to correct the affected clock when the SSCG is
enabled. The check is done in an new optional function related to each
SoC: is_sscg_enabled(). The fix is done with the other new optional
function related to each SoC: fix_sscg_deviation. If one these
functions are not present then no correction is done on the clock
frequency.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Tested-by: Leigh Brown <leigh@solinno.co.uk>
Link: https://lkml.kernel.org/r/1409645719-20003-2-git-send-email-gregory.clement@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

clk: mvebu: share locks between gate clocks

Refactor mvebu_clk_gating_setup() to use a common spinlock instead of a
unique lock for every instance of a struct clk_gating_ctrl object. This
will be used later for a separate mux clock type that shares a register
with gate clock types and needs to use the same lock to protect access
to the register.

Cc: Andrew Lunn <andrew@lunn.ch>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

clk: mvebu: add missing iounmap

Add missing iounmap to setup error path.

Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

clk: mvebu: add common clock functions for core clk and clk gating

Based on the current common functions for core clocks and clock
gating control, new common functions are joined in a single file.
Given the opportunity, names of functions and structs are unified,
and also a Kconfig entry is added.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>