linux/drivers/clk/ti/clockdomain.c

155 lines
4.4 KiB
C

/*
* OMAP clockdomain support
*
* Copyright (C) 2013 Texas Instruments, Inc.
*
* Tero Kristo <t-kristo@ti.com>
*
* 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.
*
* This program is distributed "as is" WITHOUT ANY WARRANTY of any
* kind, whether express or implied; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/clk/ti.h>
#include "clock.h"
#undef pr_fmt
#define pr_fmt(fmt) "%s: " fmt, __func__
/**
* omap2_clkops_enable_clkdm - increment usecount on clkdm of @hw
* @hw: struct clk_hw * of the clock being enabled
*
* Increment the usecount of the clockdomain of the clock pointed to
* by @hw; if the usecount is 1, the clockdomain will be "enabled."
* Only needed for clocks that don't use omap2_dflt_clk_enable() as
* their enable function pointer. Passes along the return value of
* clkdm_clk_enable(), -EINVAL if @hw is not associated with a
* clockdomain, or 0 if clock framework-based clockdomain control is
* not implemented.
*/
int omap2_clkops_enable_clkdm(struct clk_hw *hw)
{
struct clk_hw_omap *clk;
int ret = 0;
clk = to_clk_hw_omap(hw);
if (unlikely(!clk->clkdm)) {
pr_err("%s: %s: no clkdm set ?!\n", __func__,
clk_hw_get_name(hw));
return -EINVAL;
}
if (unlikely(clk->enable_reg))
pr_err("%s: %s: should use dflt_clk_enable ?!\n", __func__,
clk_hw_get_name(hw));
if (ti_clk_get_features()->flags & TI_CLK_DISABLE_CLKDM_CONTROL) {
pr_err("%s: %s: clkfw-based clockdomain control disabled ?!\n",
__func__, clk_hw_get_name(hw));
return 0;
}
ret = ti_clk_ll_ops->clkdm_clk_enable(clk->clkdm, hw->clk);
WARN(ret, "%s: could not enable %s's clockdomain %s: %d\n",
__func__, clk_hw_get_name(hw), clk->clkdm_name, ret);
return ret;
}
/**
* omap2_clkops_disable_clkdm - decrement usecount on clkdm of @hw
* @hw: struct clk_hw * of the clock being disabled
*
* Decrement the usecount of the clockdomain of the clock pointed to
* by @hw; if the usecount is 0, the clockdomain will be "disabled."
* Only needed for clocks that don't use omap2_dflt_clk_disable() as their
* disable function pointer. No return value.
*/
void omap2_clkops_disable_clkdm(struct clk_hw *hw)
{
struct clk_hw_omap *clk;
clk = to_clk_hw_omap(hw);
if (unlikely(!clk->clkdm)) {
pr_err("%s: %s: no clkdm set ?!\n", __func__,
clk_hw_get_name(hw));
return;
}
if (unlikely(clk->enable_reg))
pr_err("%s: %s: should use dflt_clk_disable ?!\n", __func__,
clk_hw_get_name(hw));
if (ti_clk_get_features()->flags & TI_CLK_DISABLE_CLKDM_CONTROL) {
pr_err("%s: %s: clkfw-based clockdomain control disabled ?!\n",
__func__, clk_hw_get_name(hw));
return;
}
ti_clk_ll_ops->clkdm_clk_disable(clk->clkdm, hw->clk);
}
static void __init of_ti_clockdomain_setup(struct device_node *node)
{
struct clk *clk;
struct clk_hw *clk_hw;
const char *clkdm_name = node->name;
int i;
unsigned int num_clks;
num_clks = of_clk_get_parent_count(node);
for (i = 0; i < num_clks; i++) {
clk = of_clk_get(node, i);
if (IS_ERR(clk)) {
pr_err("%s: Failed get %s' clock nr %d (%ld)\n",
__func__, node->full_name, i, PTR_ERR(clk));
continue;
}
clk_hw = __clk_get_hw(clk);
if (clk_hw_get_flags(clk_hw) & CLK_IS_BASIC) {
pr_warn("can't setup clkdm for basic clk %s\n",
__clk_get_name(clk));
continue;
}
to_clk_hw_omap(clk_hw)->clkdm_name = clkdm_name;
omap2_init_clk_clkdm(clk_hw);
}
}
static const struct of_device_id ti_clkdm_match_table[] __initconst = {
{ .compatible = "ti,clockdomain" },
{ }
};
/**
* ti_dt_clockdomains_setup - setup device tree clockdomains
*
* Initializes clockdomain nodes for a SoC. This parses through all the
* nodes with compatible = "ti,clockdomain", and add the clockdomain
* info for all the clocks listed under these. This function shall be
* called after rest of the DT clock init has completed and all
* clock nodes have been registered.
*/
void __init ti_dt_clockdomains_setup(void)
{
struct device_node *np;
for_each_matching_node(np, ti_clkdm_match_table) {
of_ti_clockdomain_setup(np);
}
}