linux/drivers/clk/tegra/clk-pll-out.c

124 lines
3.1 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/kernel.h>
#include <linux/io.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/clk-provider.h>
#include <linux/clk.h>
#include "clk.h"
#define pll_out_enb(p) (BIT(p->enb_bit_idx))
#define pll_out_rst(p) (BIT(p->rst_bit_idx))
static int clk_pll_out_is_enabled(struct clk_hw *hw)
{
struct tegra_clk_pll_out *pll_out = to_clk_pll_out(hw);
u32 val = readl_relaxed(pll_out->reg);
int state;
state = (val & pll_out_enb(pll_out)) ? 1 : 0;
if (!(val & (pll_out_rst(pll_out))))
state = 0;
return state;
}
static int clk_pll_out_enable(struct clk_hw *hw)
{
struct tegra_clk_pll_out *pll_out = to_clk_pll_out(hw);
unsigned long flags = 0;
u32 val;
if (pll_out->lock)
spin_lock_irqsave(pll_out->lock, flags);
val = readl_relaxed(pll_out->reg);
val |= (pll_out_enb(pll_out) | pll_out_rst(pll_out));
writel_relaxed(val, pll_out->reg);
udelay(2);
if (pll_out->lock)
spin_unlock_irqrestore(pll_out->lock, flags);
return 0;
}
static void clk_pll_out_disable(struct clk_hw *hw)
{
struct tegra_clk_pll_out *pll_out = to_clk_pll_out(hw);
unsigned long flags = 0;
u32 val;
if (pll_out->lock)
spin_lock_irqsave(pll_out->lock, flags);
val = readl_relaxed(pll_out->reg);
val &= ~(pll_out_enb(pll_out) | pll_out_rst(pll_out));
writel_relaxed(val, pll_out->reg);
udelay(2);
if (pll_out->lock)
spin_unlock_irqrestore(pll_out->lock, flags);
}
const struct clk_ops tegra_clk_pll_out_ops = {
.is_enabled = clk_pll_out_is_enabled,
.enable = clk_pll_out_enable,
.disable = clk_pll_out_disable,
};
struct clk *tegra_clk_register_pll_out(const char *name,
const char *parent_name, void __iomem *reg, u8 enb_bit_idx,
u8 rst_bit_idx, unsigned long flags, u8 pll_out_flags,
spinlock_t *lock)
{
struct tegra_clk_pll_out *pll_out;
struct clk *clk;
struct clk_init_data init;
pll_out = kzalloc(sizeof(*pll_out), GFP_KERNEL);
if (!pll_out)
return ERR_PTR(-ENOMEM);
init.name = name;
init.ops = &tegra_clk_pll_out_ops;
init.parent_names = (parent_name ? &parent_name : NULL);
init.num_parents = (parent_name ? 1 : 0);
init.flags = flags;
pll_out->reg = reg;
pll_out->enb_bit_idx = enb_bit_idx;
pll_out->rst_bit_idx = rst_bit_idx;
pll_out->flags = pll_out_flags;
pll_out->lock = lock;
/* Data in .init is copied by clk_register(), so stack variable OK */
pll_out->hw.init = &init;
clk = clk_register(NULL, &pll_out->hw);
if (IS_ERR(clk))
kfree(pll_out);
return clk;
}