kernel/drivers/clk/clkdev.c, branch linux-5.1.y

clkdev: Hold clocks_mutex while iterating clocks list

2019-04-18T20:33:13Z

We recently introduced a change to support devm clk lookups. That change introduced a code-path that used clk_find() without holding the 'clocks_mutex'. Unfortunately, clk_find() iterates over the 'clocks' list and so we need to prevent the list from being modified at the same time. Do this by holding the mutex and checking to make sure it's held while iterating the list. Note, we don't really care if the lookup is freed after we find it with clk_find() because we're just doing a pointer comparison, but if we did care we would need to keep holding the mutex while we dereference the clk_lookup pointer. Fixes: 3eee6c7d119c ("clkdev: add managed clkdev lookup registration") Cc: Miquel Raynal Cc: Jerome Brunet Cc: Russell King Cc: Michael Turquette Cc: Jeffrey Hugo Cc: Chen-Yu Tsai Cc: Matti Vaittinen Acked-by: Matti Vaittinen Tested-by: Jeffrey Hugo Signed-off-by: Stephen Boyd

Merge branch 'clk-parent-rewrite' (early part) into clk-next

2019-03-08T18:35:01Z

* 'clk-parent-rewrite' (early part): clk: Move of_clk_*() APIs into clk.c from clkdev.c clk: Inform the core about consumer devices clk: Introduce of_clk_get_hw_from_clkspec() clk: core: clarify the check for runtime PM clk: Combine __clk_get() and __clk_create_clk()

Merge branches 'clk-optional', 'clk-devm-clkdev-register', 'clk-allwinner', 'clk-meson' and 'clk-renesas' into clk-next

2019-03-08T18:27:21Z

- Add a {devm_}clk_get_optional() API - Add devm_clk_hw_register_clkdev() API to manage clkdev lookups * clk-optional: clk: Add (devm_)clk_get_optional() functions clk: Add comment about __of_clk_get_by_name() error values * clk-devm-clkdev-register: clk: clk-st: avoid clkdev lookup leak at remove clk: clk-max77686: Clean clkdev lookup leak and use devm clkdev: add managed clkdev lookup registration * clk-allwinner: clk: sunxi-ng: sun8i-a23: Enable PLL-MIPI LDOs when ungating it * clk-meson: (22 commits) clk: meson: meson8b: fix the naming of the APB clocks dt-bindings: clock: meson8b: add APB clock definition clk: meson: Add G12A AO Clock + Reset Controller dt-bindings: clk: add G12A AO Clock and Reset Bindings clk: meson: factorise meson64 peripheral clock controller drivers clk: meson: g12a: add peripheral clock controller dt-bindings: clk: meson: add g12a periph clock controller bindings clk: meson: pll: update driver for the g12a clk: meson: rework and clean drivers dependencies clk: meson: axg-audio does not require syscon clk: meson: use CONFIG_ARCH_MESON to enter meson clk directory clk: export some clk_hw function symbols for module drivers clk: meson: ao-clkc: claim clock controller input clocks from DT clk: meson: axg: claim clock controller input clock from DT clk: meson: gxbb: claim clock controller input clock from DT clk: meson: meson8b: add the GPU clock tree clk: meson: meson8b: use a separate clock table for Meson8 clk: meson: axg-ao: add 32k generation subtree clk: meson: gxbb-ao: replace cec-32k with the dual divider clk: meson: add dual divider clock driver ... * clk-renesas: clk: renesas: r8a774a1: Fix LAST_DT_CORE_CLK clk: renesas: r8a774c0: Fix LAST_DT_CORE_CLK clk: renesas: r8a774c0: Add TMU clock clk: renesas: r8a77980: Add RPC clocks clk: renesas: rcar-gen3: Add RPC clocks clk: renesas: rcar-gen3: Add spinlock clk: renesas: rcar-gen3: Factor out cpg_reg_modify() clk: renesas: r8a774c0: Correct parent clock of DU clk: renesas: r8a774a1: Add missing CANFD clock clk: renesas: r8a774c0: Add missing CANFD clock

clk: Move of_clk_*() APIs into clk.c from clkdev.c

2019-03-01T19:17:22Z

The API between clk.c and clkdev.c is purely getting the clk_hw structure (or the struct clk if it's not CCF) and then turning that struct clk_hw pointer into a struct clk pointer via clk_hw_create_clk(). There's no need to complicate clkdev.c with these DT parsing details that are only relevant to the common clk framework. Move the DT parsing logic into the core framework and just expose the APIs to get a clk_hw pointer and convert it. Cc: Miquel Raynal Cc: Jerome Brunet Cc: Russell King Cc: Michael Turquette Cc: Jeffrey Hugo Cc: Chen-Yu Tsai Signed-off-by: Stephen Boyd

clk: Inform the core about consumer devices

2019-03-01T19:17:22Z

We'd like to have a pointer to the device that's consuming a particular clk in the clk framework so we can link the consumer to the clk provider with a PM device link. Add a device argument to clk_hw_create_clk() for this so it can be used in subsequent patches to add and remove the link. Cc: Miquel Raynal Cc: Jerome Brunet Cc: Russell King Cc: Michael Turquette Cc: Jeffrey Hugo Cc: Chen-Yu Tsai Signed-off-by: Stephen Boyd

clk: Introduce of_clk_get_hw_from_clkspec()

2019-03-01T19:17:22Z

We want to get struct clk_hw pointers from a DT clk specifier (i.e. a clocks property) so that we can find parent clks without searching for globally unique clk names. This should save time by avoiding the global string search for clks that are external to the clock controller providing the clk and let us move away from string comparisons in general. Introduce of_clk_get_hw_from_clkspec() which is largely the DT parsing part of finding clks implemented in clkdev.c and have that return a clk_hw pointer instead of converting that into a clk pointer. This lets us push up the clk pointer creation to the caller in clk_get() and avoids the need to push the dev_id and con_id throughout the DT parsing code. Cc: Miquel Raynal Cc: Jerome Brunet Cc: Russell King Cc: Michael Turquette Cc: Jeffrey Hugo Cc: Chen-Yu Tsai Signed-off-by: Stephen Boyd

clk: Combine __clk_get() and __clk_create_clk()

2019-03-01T19:16:14Z

The __clk_get() function is practically a private clk implementation detail now. No architecture defines it, and given that new code should be using the common clk framework there isn't a need for it to keep existing just to serve clkdev purposes. Let's fold it into the __clk_create_clk() function and make that a little more generic by renaming it to clk_hw_create_clk(). This will allow the framework to create a struct clk handle to a particular clk_hw pointer and link it up as a consumer wherever that's needed. Doing this also lets us get rid of the __clk_free_clk() API that had to be kept in sync with __clk_put(). Splitting that API up into the "link and unlink from consumer list" phase and "free the clk pointer" phase allows us to reuse that logic in a couple places, simplifying the code. Cc: Miquel Raynal Cc: Jerome Brunet Cc: Russell King Cc: Michael Turquette Cc: Jeffrey Hugo Cc: Chen-Yu Tsai Signed-off-by: Stephen Boyd

clkdev: add managed clkdev lookup registration

2019-02-06T18:35:02Z

Clkdev registration lacks of managed registration functions and it seems few drivers do not drop clkdev lookups at exit. Add devm_clk_hw_register_clkdev and devm_clk_release_clkdev to ease lookup releasing at exit. Signed-off-by: Matti Vaittinen Signed-off-by: Stephen Boyd

clk: Add comment about __of_clk_get_by_name() error values

2019-02-06T18:32:42Z

It's not immediately obvious from the code that failure to get a clock provider can return either -ENOENT or -EINVAL. Therefore, add a comment to highlight this. Signed-off-by: Phil Edworthy Reviewed-by: Andy Shevchenko Cc: Russell King [sboyd@kernel.org: Fix comment to be proper C with ==] Signed-off-by: Stephen Boyd

ARM: 8778/1: clkdev: don't call __of_clk_get_by_name() unnecessarily from clk_get()

2018-08-13T15:27:52Z

The way this function is implemented caused some confusion when converting the TI DaVinci platform to using the common clock framework. Current kernel supports booting DaVinci boards both in device tree as well as legacy, board-file mode. In the latter, we always end up calling clk_get_sys() as of_node is NULL and __of_clk_get_by_name() returns -ENOENT. It was not obvious at first glance how clk_get(dev, NULL) will work in board-file mode since we always call __of_clk_get_by_name(). Let's make it clearer by checking if of_node is NULL and skipping right to clk_get_sys(). Cc: Sekhar Nori Cc: Kevin Hilman Cc: David Lechner Reviewed-by: David Lechner Reviewed-by: Sekhar Nori Signed-off-by: Bartosz Golaszewski Signed-off-by: Russell King