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author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-05-26 12:42:29 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-05-26 12:42:29 -0700 |
commit | 27953437059c64d14086196eb96f43c78caa9db3 (patch) | |
tree | 0cfd5fb21262a6db3de0c64462847b4c0c43e9df /drivers/clk/clk-fixed-factor.c | |
parent | 2c757fd5d1a92086f225a75a8fac7cab242d11b0 (diff) | |
parent | 3c0dec5f58b3c7b3627715126d1bf9b030a076f0 (diff) | |
download | linux-27953437059c64d14086196eb96f43c78caa9db3.tar.gz linux-27953437059c64d14086196eb96f43c78caa9db3.tar.bz2 linux-27953437059c64d14086196eb96f43c78caa9db3.zip |
Merge tag 'clock' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull arm-soc clock driver changes from Olof Johansson:
"The new clock subsystem was merged in linux-3.4 without any users,
this now moves the first three platforms over to it: imx, mxs and
spear.
The series also contains the changes for the clock subsystem itself,
since Mike preferred to have it together with the platforms that
require these changes, in order to avoid interdependencies and
conflicts."
Fix up trivial conflicts in arch/arm/mach-kirkwood/common.c (code
removed in one branch, added OF support in another) and
drivers/dma/imx-sdma.c (independent changes next to each other).
* tag 'clock' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (97 commits)
clk: Fix CLK_SET_RATE_GATE flag validation in clk_set_rate().
clk: Provide dummy clk_unregister()
SPEAr: Update defconfigs
SPEAr: Add SMI NOR partition info in dts files
SPEAr: Switch to common clock framework
SPEAr: Call clk_prepare() before calling clk_enable
SPEAr: clk: Add General Purpose Timer Synthesizer clock
SPEAr: clk: Add Fractional Synthesizer clock
SPEAr: clk: Add Auxiliary Synthesizer clock
SPEAr: clk: Add VCO-PLL Synthesizer clock
SPEAr: Add DT bindings for SPEAr's timer
ARM i.MX: remove now unused clock files
ARM: i.MX6: implement clocks using common clock framework
ARM i.MX35: implement clocks using common clock framework
ARM i.MX5: implement clocks using common clock framework
ARM: Kirkwood: Replace clock gating
ARM: Orion: Audio: Add clk/clkdev support
ARM: Orion: PCIE: Add support for clk
ARM: Orion: XOR: Add support for clk
ARM: Orion: CESA: Add support for clk
...
Diffstat (limited to 'drivers/clk/clk-fixed-factor.c')
-rw-r--r-- | drivers/clk/clk-fixed-factor.c | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/drivers/clk/clk-fixed-factor.c b/drivers/clk/clk-fixed-factor.c new file mode 100644 index 000000000000..c8c003e217ad --- /dev/null +++ b/drivers/clk/clk-fixed-factor.c @@ -0,0 +1,95 @@ +/* + * Copyright (C) 2011 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Standard functionality for the common clock API. + */ +#include <linux/module.h> +#include <linux/clk-provider.h> +#include <linux/slab.h> +#include <linux/err.h> + +/* + * DOC: basic fixed multiplier and divider clock that cannot gate + * + * Traits of this clock: + * prepare - clk_prepare only ensures that parents are prepared + * enable - clk_enable only ensures that parents are enabled + * rate - rate is fixed. clk->rate = parent->rate / div * mult + * parent - fixed parent. No clk_set_parent support + */ + +#define to_clk_fixed_factor(_hw) container_of(_hw, struct clk_fixed_factor, hw) + +static unsigned long clk_factor_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_fixed_factor *fix = to_clk_fixed_factor(hw); + + return parent_rate * fix->mult / fix->div; +} + +static long clk_factor_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + struct clk_fixed_factor *fix = to_clk_fixed_factor(hw); + + if (__clk_get_flags(hw->clk) & CLK_SET_RATE_PARENT) { + unsigned long best_parent; + + best_parent = (rate / fix->mult) * fix->div; + *prate = __clk_round_rate(__clk_get_parent(hw->clk), + best_parent); + } + + return (*prate / fix->div) * fix->mult; +} + +static int clk_factor_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + return 0; +} + +struct clk_ops clk_fixed_factor_ops = { + .round_rate = clk_factor_round_rate, + .set_rate = clk_factor_set_rate, + .recalc_rate = clk_factor_recalc_rate, +}; +EXPORT_SYMBOL_GPL(clk_fixed_factor_ops); + +struct clk *clk_register_fixed_factor(struct device *dev, const char *name, + const char *parent_name, unsigned long flags, + unsigned int mult, unsigned int div) +{ + struct clk_fixed_factor *fix; + struct clk_init_data init; + struct clk *clk; + + fix = kmalloc(sizeof(*fix), GFP_KERNEL); + if (!fix) { + pr_err("%s: could not allocate fixed factor clk\n", __func__); + return ERR_PTR(-ENOMEM); + } + + /* struct clk_fixed_factor assignments */ + fix->mult = mult; + fix->div = div; + fix->hw.init = &init; + + init.name = name; + init.ops = &clk_fixed_factor_ops; + init.flags = flags; + init.parent_names = &parent_name; + init.num_parents = 1; + + clk = clk_register(dev, &fix->hw); + + if (IS_ERR(clk)) + kfree(fix); + + return clk; +} |