diff options
author | 2015-08-04 12:17:53 -0700 | |
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committer | 2015-08-04 15:44:42 -0700 | |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/clk/clk-fixed-factor.c | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/clk/clk-fixed-factor.c')
-rw-r--r-- | kernel/drivers/clk/clk-fixed-factor.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/kernel/drivers/clk/clk-fixed-factor.c b/kernel/drivers/clk/clk-fixed-factor.c new file mode 100644 index 000000000..d9e3f671c --- /dev/null +++ b/kernel/drivers/clk/clk-fixed-factor.c @@ -0,0 +1,136 @@ +/* + * 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> +#include <linux/of.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); + unsigned long long int rate; + + rate = (unsigned long long int)parent_rate * fix->mult; + do_div(rate, fix->div); + return (unsigned long)rate; +} + +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; +} +EXPORT_SYMBOL_GPL(clk_register_fixed_factor); + +#ifdef CONFIG_OF +/** + * of_fixed_factor_clk_setup() - Setup function for simple fixed factor clock + */ +void __init of_fixed_factor_clk_setup(struct device_node *node) +{ + struct clk *clk; + const char *clk_name = node->name; + const char *parent_name; + u32 div, mult; + + if (of_property_read_u32(node, "clock-div", &div)) { + pr_err("%s Fixed factor clock <%s> must have a clock-div property\n", + __func__, node->name); + return; + } + + if (of_property_read_u32(node, "clock-mult", &mult)) { + pr_err("%s Fixed factor clock <%s> must have a clock-mult property\n", + __func__, node->name); + return; + } + + of_property_read_string(node, "clock-output-names", &clk_name); + parent_name = of_clk_get_parent_name(node, 0); + + clk = clk_register_fixed_factor(NULL, clk_name, parent_name, 0, + mult, div); + if (!IS_ERR(clk)) + of_clk_add_provider(node, of_clk_src_simple_get, clk); +} +EXPORT_SYMBOL_GPL(of_fixed_factor_clk_setup); +CLK_OF_DECLARE(fixed_factor_clk, "fixed-factor-clock", + of_fixed_factor_clk_setup); +#endif |