/* * Copyright (C) 2011 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * Standard functionality for the common clock API. */ #include <linux/module.h> #include <linux/clk-provider.h> #include <linux/slab.h> #include <linux/err.h> /* * 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) static unsigned long clk_factor_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { struct clk_fixed_factor *fix = to_clk_fixed_factor(hw); return parent_rate * fix->mult / fix->div; } static long clk_factor_round_rate(struct clk_hw *hw, unsigned long rate, unsigned long *prate) { struct clk_fixed_factor *fix = to_clk_fixed_factor(hw); if (__clk_get_flags(hw->clk) & CLK_SET_RATE_PARENT) { unsigned long best_parent; best_parent = (rate / fix->mult) * fix->div; *prate = __clk_round_rate(__clk_get_parent(hw->clk), best_parent); } return (*prate / fix->div) * fix->mult; } static int clk_factor_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate) { return 0; } struct clk_ops clk_fixed_factor_ops = { .round_rate = clk_factor_round_rate, .set_rate = clk_factor_set_rate, .recalc_rate = clk_factor_recalc_rate, }; EXPORT_SYMBOL_GPL(clk_fixed_factor_ops); 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) { struct clk_fixed_factor *fix; struct clk_init_data init; struct clk *clk; fix = kmalloc(sizeof(*fix), GFP_KERNEL); if (!fix) { pr_err("%s: could not allocate fixed factor clk\n", __func__); return ERR_PTR(-ENOMEM); } /* struct clk_fixed_factor assignments */ fix->mult = mult; fix->div = div; fix->hw.init = &init; init.name = name; init.ops = &clk_fixed_factor_ops; init.flags = flags | CLK_IS_BASIC; init.parent_names = &parent_name; init.num_parents = 1; clk = clk_register(dev, &fix->hw); if (IS_ERR(clk)) kfree(fix); return clk; }