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author | Sascha Hauer <s.hauer@pengutronix.de> | 2012-09-20 22:03:42 +0200 |
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committer | Sascha Hauer <s.hauer@pengutronix.de> | 2012-10-04 15:19:55 +0200 |
commit | f2e2e596a221c146082821aa4d9ae249fe9d561a (patch) | |
tree | 2f267a4ad613fcc06bd6a02235c364a4dc2c15e3 /drivers/clk/clk-fixed-factor.c | |
parent | 89b710e5094fb5721b18c6501a7c813df9f40b14 (diff) | |
download | barebox-f2e2e596a221c146082821aa4d9ae249fe9d561a.tar.gz barebox-f2e2e596a221c146082821aa4d9ae249fe9d561a.tar.xz |
clk: initial common clk support
This adds barebox common clk support loosely based on the Kernel common
clk support. differences are:
- barebox does not need prepare/unprepare
- no parent rate propagation for set_rate
- struct clk is not really encapsulated from the drivers
Along with the clk support we have support for some basic clk building
blocks:
- clk-fixed
- clk-fixed-factor
- clk-mux
- clk-divider
clk-fixed and clk-fixed-factor are completely generic, clk-mux and clk-divider
are currently the way i.MX muxes/dividers are implemented.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Diffstat (limited to 'drivers/clk/clk-fixed-factor.c')
-rw-r--r-- | drivers/clk/clk-fixed-factor.c | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/drivers/clk/clk-fixed-factor.c b/drivers/clk/clk-fixed-factor.c new file mode 100644 index 0000000000..52e7c16c49 --- /dev/null +++ b/drivers/clk/clk-fixed-factor.c @@ -0,0 +1,63 @@ +/* + * clk-fixed-factor.c - generic barebox clock support. Based on Linux clk support + * + * Copyright (c) 2012 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ +#include <common.h> +#include <io.h> +#include <malloc.h> +#include <linux/clk.h> +#include <linux/err.h> + +struct clk_fixed_factor { + struct clk clk; + int mult; + int div; + const char *parent; +}; + +static unsigned long clk_fixed_factor_recalc_rate(struct clk *clk, + unsigned long parent_rate) +{ + struct clk_fixed_factor *f = container_of(clk, struct clk_fixed_factor, clk); + + return (parent_rate / f->div) * f->mult; +} + +struct clk_ops clk_fixed_factor_ops = { + .recalc_rate = clk_fixed_factor_recalc_rate, +}; + +struct clk *clk_fixed_factor(const char *name, + const char *parent, unsigned int mult, unsigned int div) +{ + struct clk_fixed_factor *f = xzalloc(sizeof(*f)); + int ret; + + f->mult = mult; + f->div = div; + f->parent = parent; + f->clk.ops = &clk_fixed_factor_ops; + f->clk.name = name; + f->clk.parent_names = &f->parent; + f->clk.num_parents = 1; + + ret = clk_register(&f->clk); + if (ret) { + free(f); + return ERR_PTR(ret); + } + + return &f->clk; +} |