From mboxrd@z Thu Jan 1 00:00:00 1970 From: philipp.zabel@gmail.com (Philipp Zabel) Date: Fri, 23 Mar 2012 08:41:29 +0100 Subject: [PATCH 1/8] clk: add a fixed factor clock In-Reply-To: <1332164166-6055-2-git-send-email-s.hauer@pengutronix.de> References: <1332164166-6055-1-git-send-email-s.hauer@pengutronix.de> <1332164166-6055-2-git-send-email-s.hauer@pengutronix.de> Message-ID: <1332488489.2876.8.camel@flow> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Am Montag, den 19.03.2012, 14:35 +0100 schrieb Sascha Hauer: > Having fixed factors/dividers in hardware is a common pattern, so > add a clock doing this. Currently no rate propagation is supported. Also, could I convince you to move struct clk_fixed_factor into clk-provider.h and provide a DEFINE_CLK_FIXED_FACTOR macro to align with the other basic clocks? --- drivers/clk/clk-fixed-factor.c | 15 +++++++++------ include/linux/clk-private.h | 28 ++++++++++++++++++++++++++++ include/linux/clk-provider.h | 19 +++++++++++++++++++ 3 files changed, 56 insertions(+), 6 deletions(-) diff --git a/drivers/clk/clk-fixed-factor.c b/drivers/clk/clk-fixed-factor.c index d99b842..8ca427a 100644 --- a/drivers/clk/clk-fixed-factor.c +++ b/drivers/clk/clk-fixed-factor.c @@ -12,12 +12,15 @@ #include #include -struct clk_fixed_factor { - struct clk_hw hw; - unsigned int mult; - unsigned int div; - char *parent[1]; -}; +/* + * 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) diff --git a/include/linux/clk-private.h b/include/linux/clk-private.h index 5e4312b..9501eab 100644 --- a/include/linux/clk-private.h +++ b/include/linux/clk-private.h @@ -170,6 +170,34 @@ extern struct clk_ops clk_mux_ops; .flags = _flags, \ }; +extern struct clk_ops clk_fixed_factor_ops; + +#define DEFINE_CLK_FIXED_FACTOR(_name, _parent_name, \ + _parent_ptr, _flags, \ + _mult, _div) \ + static struct clk _name; \ + static struct clk *_name##_parents[] = { \ + _parent_ptr, \ + }; \ + static struct clk_fixed_factor _name##_hw = { \ + .hw = { \ + .clk = &_name, \ + }, \ + .mult = _mult, \ + .div = _div, \ + .parent[0] = _parent_name, \ + }; \ + static struct clk _name = { \ + .name = #_name, \ + .ops = &clk_fixed_factor_ops, \ + .hw = &_name##_hw.hw, \ + .parent_names = _name##_hw.parent, \ + .num_parents = \ + ARRAY_SIZE(_name##_hw.parent), \ + .parents = _name##_parents, \ + .flags = _flags, \ + }; + /** * __clk_init - initialize the data structures in a struct clk * @dev: device initializing this clk, placeholder for now diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h index 21ca2f8..b58f846 100644 --- a/include/linux/clk-provider.h +++ b/include/linux/clk-provider.h @@ -257,6 +257,25 @@ struct clk *clk_register_mux(struct device *dev, const char *name, void __iomem *reg, u8 shift, u8 width, u8 clk_mux_flags, spinlock_t *lock); +/** + * struct clk_fixed_factor - fixed multiplier and divider clock + * + * @hw: handle between common and hardware-specific interfaces + * @mult: multiplier + * @div: divider + * + * Clock with a fixed multiplier and divider. The output frequency is the + * parent clock rate divided by div and multiplied by mult. + * Implements .recalc_rate, .set_rate and .round_rate + */ + +struct clk_fixed_factor { + struct clk_hw hw; + unsigned int mult; + unsigned int div; + char *parent[1]; +}; + 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); -- 1.7.9.1