From 83501ff0a5032dfbd63ab1ca9d9d25b97ec49fb9 Mon Sep 17 00:00:00 2001 From: Tero Kristo Date: Fri, 3 Oct 2014 16:57:12 +0300 Subject: ARM: OMAP4: clock: add support for determine_rate for omap4 regm4xen DPLL Similarly to OMAP3 noncore DPLL, the implementation of this DPLL clock type is wrong. This patch adds basic functionality for determine_rate for this clock type which will be taken into use in the patches following later. Signed-off-by: Tero Kristo Signed-off-by: Paul Walmsley --- arch/arm/mach-omap2/dpll44xx.c | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) (limited to 'arch/arm/mach-omap2/dpll44xx.c') diff --git a/arch/arm/mach-omap2/dpll44xx.c b/arch/arm/mach-omap2/dpll44xx.c index 4613f1e86988..535822fcf4bb 100644 --- a/arch/arm/mach-omap2/dpll44xx.c +++ b/arch/arm/mach-omap2/dpll44xx.c @@ -207,3 +207,44 @@ out: return dd->last_rounded_rate; } + +/** + * omap4_dpll_regm4xen_determine_rate - determine rate for a DPLL + * @hw: pointer to the clock to determine rate for + * @rate: target rate for the DPLL + * @best_parent_rate: pointer for returning best parent rate + * @best_parent_clk: pointer for returning best parent clock + * + * Determines which DPLL mode to use for reaching a desired rate. + * Checks whether the DPLL shall be in bypass or locked mode, and if + * locked, calculates the M,N values for the DPLL via round-rate. + * Returns a positive clock rate with success, negative error value + * in failure. + */ +long omap4_dpll_regm4xen_determine_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *best_parent_rate, + struct clk **best_parent_clk) +{ + struct clk_hw_omap *clk = to_clk_hw_omap(hw); + struct dpll_data *dd; + + if (!hw || !rate) + return -EINVAL; + + dd = clk->dpll_data; + if (!dd) + return -EINVAL; + + if (__clk_get_rate(dd->clk_bypass) == rate && + (dd->modes & (1 << DPLL_LOW_POWER_BYPASS))) { + *best_parent_clk = dd->clk_bypass; + } else { + rate = omap4_dpll_regm4xen_round_rate(hw, rate, + best_parent_rate); + *best_parent_clk = dd->clk_ref; + } + + *best_parent_rate = rate; + + return rate; +} -- cgit v1.2.3