linux/drivers/clk/tegra/clk-audio-sync.c

88 lines
2.3 KiB
C

/*
* Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/clk-provider.h>
#include <linux/slab.h>
#include <linux/err.h>
#include "clk.h"
static unsigned long clk_sync_source_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct tegra_clk_sync_source *sync = to_clk_sync_source(hw);
return sync->rate;
}
static long clk_sync_source_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *prate)
{
struct tegra_clk_sync_source *sync = to_clk_sync_source(hw);
if (rate > sync->max_rate)
return -EINVAL;
else
return rate;
}
static int clk_sync_source_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct tegra_clk_sync_source *sync = to_clk_sync_source(hw);
sync->rate = rate;
return 0;
}
const struct clk_ops tegra_clk_sync_source_ops = {
.round_rate = clk_sync_source_round_rate,
.set_rate = clk_sync_source_set_rate,
.recalc_rate = clk_sync_source_recalc_rate,
};
struct clk *tegra_clk_register_sync_source(const char *name,
unsigned long rate, unsigned long max_rate)
{
struct tegra_clk_sync_source *sync;
struct clk_init_data init;
struct clk *clk;
sync = kzalloc(sizeof(*sync), GFP_KERNEL);
if (!sync) {
pr_err("%s: could not allocate sync source clk\n", __func__);
return ERR_PTR(-ENOMEM);
}
sync->rate = rate;
sync->max_rate = max_rate;
init.ops = &tegra_clk_sync_source_ops;
init.name = name;
init.flags = CLK_IS_ROOT;
init.parent_names = NULL;
init.num_parents = 0;
/* Data in .init is copied by clk_register(), so stack variable OK */
sync->hw.init = &init;
clk = clk_register(NULL, &sync->hw);
if (IS_ERR(clk))
kfree(sync);
return clk;
}