/* * clk-fixed-factor.c - generic barebox clock support. Based on Linux clk support * * Copyright (c) 2012 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of * the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * */ #include <common.h> #include <io.h> #include <malloc.h> #include <linux/clk.h> #include <linux/err.h> struct clk_fixed_factor { struct clk clk; int mult; int div; const char *parent; }; static unsigned long clk_fixed_factor_recalc_rate(struct clk *clk, unsigned long parent_rate) { struct clk_fixed_factor *f = container_of(clk, struct clk_fixed_factor, clk); return (parent_rate / f->div) * f->mult; } static long clk_factor_round_rate(struct clk *clk, unsigned long rate, unsigned long *prate) { struct clk_fixed_factor *fix = container_of(clk, struct clk_fixed_factor, clk); if (clk->flags & CLK_SET_RATE_PARENT) { unsigned long best_parent; best_parent = (rate / fix->mult) * fix->div; *prate = clk_round_rate(clk_get_parent(clk), best_parent); } return (*prate / fix->div) * fix->mult; } static int clk_factor_set_rate(struct clk *clk, unsigned long rate, unsigned long parent_rate) { struct clk_fixed_factor *fix = container_of(clk, struct clk_fixed_factor, clk); if (clk->flags & CLK_SET_RATE_PARENT) { printk("%s: %ld -> parent %ld\n", __func__, rate, rate * fix->div / fix->mult); return clk_set_rate(clk_get_parent(clk), rate * fix->div / fix->mult); } return 0; } static struct clk_ops clk_fixed_factor_ops = { .set_rate = clk_factor_set_rate, .round_rate = clk_factor_round_rate, .recalc_rate = clk_fixed_factor_recalc_rate, }; struct clk *clk_fixed_factor(const char *name, const char *parent, unsigned int mult, unsigned int div, unsigned flags) { struct clk_fixed_factor *f = xzalloc(sizeof(*f)); int ret; f->mult = mult; f->div = div; f->parent = parent; f->clk.ops = &clk_fixed_factor_ops; f->clk.name = name; f->clk.flags = flags; f->clk.parent_names = &f->parent; f->clk.num_parents = 1; ret = clk_register(&f->clk); if (ret) { free(f); return ERR_PTR(ret); } return &f->clk; }