This patch adds clk_round_rate_parent(), a means for internal clock code to determine what a clock's rate would be if its parent changed. This is needed by the pre-change clock notifier, which passes the current clock rate and the desired clock rate to its callbacks.
An implementation is provided for the OMAP2/3 architecture (omap2_clk_round_rate_parent).. Signed-off-by: Paul Walmsley <[email protected]> --- arch/arm/mach-omap2/clock.c | 30 ++++++++++++++++++++++++++++++ arch/arm/mach-omap2/clock.h | 1 + arch/arm/mach-omap2/clock24xx.c | 1 + arch/arm/mach-omap2/clock34xx.c | 1 + arch/arm/plat-omap/include/mach/clock.h | 2 ++ 5 files changed, 35 insertions(+), 0 deletions(-) diff --git a/arch/arm/mach-omap2/clock.c b/arch/arm/mach-omap2/clock.c index 41662fd..65391ba 100644 --- a/arch/arm/mach-omap2/clock.c +++ b/arch/arm/mach-omap2/clock.c @@ -871,6 +871,36 @@ struct clk *omap2_clk_get_parent(struct clk *clk) return clk->parent; } +/** + * omap2_clk_round_rate_parent - return the rate for @clk if parent were changed + * @clk: struct clk that may change parents + * @new_parent: the struct clk that @clk may be reparented under + * + * Given a struct clk @clk and a new parent struct clk @new_parent, + * determine what @clk's rate would be after the reparent operation. + * Returns the new clock rate or -EINVAL upon error. + */ +long omap2_clk_round_rate_parent(struct clk *clk, struct clk *new_parent) +{ + u32 field_val, parent_div; + long rate; + + if (!clk->clksel || !new_parent) + return -EINVAL; + + parent_div = _omap2_clksel_get_src_field(new_parent, clk, &field_val); + if (!parent_div) + return -EINVAL; + + /* CLKSEL clocks follow their parents' rates, divided by a divisor */ + rate = new_parent->rate; + if (parent_div > 0) + rate /= parent_div; + + return rate; +} + + /* DPLL rate rounding code */ /** diff --git a/arch/arm/mach-omap2/clock.h b/arch/arm/mach-omap2/clock.h index f4d489f..af350ed 100644 --- a/arch/arm/mach-omap2/clock.h +++ b/arch/arm/mach-omap2/clock.h @@ -41,6 +41,7 @@ int omap2_clk_register(struct clk *clk); int omap2_clk_enable(struct clk *clk); void omap2_clk_disable(struct clk *clk); long omap2_clk_round_rate(struct clk *clk, unsigned long rate); +long omap2_clk_round_rate_parent(struct clk *clk, struct clk *new_parent); int omap2_clk_set_rate(struct clk *clk, unsigned long rate); int omap2_clk_set_parent(struct clk *clk, struct clk *new_parent); int omap2_dpll_set_rate_tolerance(struct clk *clk, unsigned int tolerance); diff --git a/arch/arm/mach-omap2/clock24xx.c b/arch/arm/mach-omap2/clock24xx.c index 53864c0..3f75524 100644 --- a/arch/arm/mach-omap2/clock24xx.c +++ b/arch/arm/mach-omap2/clock24xx.c @@ -448,6 +448,7 @@ static struct clk_functions omap2_clk_functions = { .clk_enable = omap2_clk_enable, .clk_disable = omap2_clk_disable, .clk_round_rate = omap2_clk_round_rate, + .clk_round_rate_parent = omap2_clk_round_rate_parent, .clk_set_rate = omap2_clk_set_rate, .clk_set_parent = omap2_clk_set_parent, .clk_get_parent = omap2_clk_get_parent, diff --git a/arch/arm/mach-omap2/clock34xx.c b/arch/arm/mach-omap2/clock34xx.c index f7ac5c1..12ff39f 100644 --- a/arch/arm/mach-omap2/clock34xx.c +++ b/arch/arm/mach-omap2/clock34xx.c @@ -635,6 +635,7 @@ static struct clk_functions omap2_clk_functions = { .clk_enable = omap2_clk_enable, .clk_disable = omap2_clk_disable, .clk_round_rate = omap2_clk_round_rate, + .clk_round_rate_parent = omap2_clk_round_rate_parent, .clk_set_rate = omap2_clk_set_rate, .clk_set_parent = omap2_clk_set_parent, .clk_get_parent = omap2_clk_get_parent, diff --git a/arch/arm/plat-omap/include/mach/clock.h b/arch/arm/plat-omap/include/mach/clock.h index db57b71..89a2662 100644 --- a/arch/arm/plat-omap/include/mach/clock.h +++ b/arch/arm/plat-omap/include/mach/clock.h @@ -121,6 +121,8 @@ struct clk_functions { int (*clk_enable)(struct clk *clk); void (*clk_disable)(struct clk *clk); long (*clk_round_rate)(struct clk *clk, unsigned long rate); + long (*clk_round_rate_parent)(struct clk *clk, + struct clk *parent); int (*clk_set_rate)(struct clk *clk, unsigned long rate); int (*clk_set_parent)(struct clk *clk, struct clk *parent); struct clk * (*clk_get_parent)(struct clk *clk); -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
