[RFC,PATCH 2/3] clk: Generic support for fixed-rate clocks
From: Ryan Mallon <hidden>
Date: 2011-02-10 23:23:36
Also in:
linux-sh, lkml
On 02/09/2011 07:41 PM, Jeremy Kerr wrote:
quoted hunk ↗ jump to hunk
Since most platforms will need a fixed-rate clock, add one. This will also serve as a basic example of an implementation of struct clk. Signed-off-by: Jeremy Kerr <redacted> --- drivers/clk/clk.c | 14 ++++++++++++++ include/linux/clk.h | 16 ++++++++++++++++ 2 files changed, 30 insertions(+)diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index c35478a..bbbdb0d 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c@@ -124,3 +124,17 @@ void __clk_put(struct clk *clk) if (clk->ops->put) clk->ops->put(clk); } + +/* clk_fixed support */ + +#define to_clk_fixed(clk) (container_of(clk, struct clk_fixed, clk)) + +static unsigned long clk_fixed_get_rate(struct clk *clk) +{ + return to_clk_fixed(clk)->rate; +} + +struct clk_ops clk_fixed_ops = { + .get_rate = clk_fixed_get_rate, +}; +EXPORT_SYMBOL_GPL(clk_fixed_ops);diff --git a/include/linux/clk.h b/include/linux/clk.h index fe806b7..e67fdb0 100644 --- a/include/linux/clk.h +++ b/include/linux/clk.h@@ -185,6 +185,22 @@ static inline void clk_common_init(struct clk *clk) mutex_init(&clk->prepare_lock); } +/* Simple fixed-rate clock */ +struct clk_fixed { + struct clk clk; + unsigned long rate; +}; + +extern struct clk_ops clk_fixed_ops; + +#define INIT_CLK_FIXED(name, r) { \ + .clk = INIT_CLK(name.clk, clk_fixed_ops), \ + .rate = (r) \ +}
A fixed clock may still have other operations such as enable/disable.
Maybe do something like this instead:
#define INIT_CLK_FIXED(name, ops, r) { \
.clk = INIT_CLK(name.clk, ops, rate), \
.clk.ops.get_rate = clk_fixed_get_rate, \
.rate = (r), \
}
That's untested though. I'm not sure if you can reliably assign
something twice in a struct initialiser?
~Ryan
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