alistair23-linux/drivers/clk/at91/clk-smd.c
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

138 lines
3.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
*/
#include <linux/clk-provider.h>
#include <linux/clkdev.h>
#include <linux/clk/at91_pmc.h>
#include <linux/of.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
#include "pmc.h"
#define SMD_DIV_SHIFT 8
#define SMD_MAX_DIV 0xf
struct at91sam9x5_clk_smd {
struct clk_hw hw;
struct regmap *regmap;
};
#define to_at91sam9x5_clk_smd(hw) \
container_of(hw, struct at91sam9x5_clk_smd, hw)
static unsigned long at91sam9x5_clk_smd_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct at91sam9x5_clk_smd *smd = to_at91sam9x5_clk_smd(hw);
unsigned int smdr;
u8 smddiv;
regmap_read(smd->regmap, AT91_PMC_SMD, &smdr);
smddiv = (smdr & AT91_PMC_SMD_DIV) >> SMD_DIV_SHIFT;
return parent_rate / (smddiv + 1);
}
static long at91sam9x5_clk_smd_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *parent_rate)
{
unsigned long div;
unsigned long bestrate;
unsigned long tmp;
if (rate >= *parent_rate)
return *parent_rate;
div = *parent_rate / rate;
if (div > SMD_MAX_DIV)
return *parent_rate / (SMD_MAX_DIV + 1);
bestrate = *parent_rate / div;
tmp = *parent_rate / (div + 1);
if (bestrate - rate > rate - tmp)
bestrate = tmp;
return bestrate;
}
static int at91sam9x5_clk_smd_set_parent(struct clk_hw *hw, u8 index)
{
struct at91sam9x5_clk_smd *smd = to_at91sam9x5_clk_smd(hw);
if (index > 1)
return -EINVAL;
regmap_update_bits(smd->regmap, AT91_PMC_SMD, AT91_PMC_SMDS,
index ? AT91_PMC_SMDS : 0);
return 0;
}
static u8 at91sam9x5_clk_smd_get_parent(struct clk_hw *hw)
{
struct at91sam9x5_clk_smd *smd = to_at91sam9x5_clk_smd(hw);
unsigned int smdr;
regmap_read(smd->regmap, AT91_PMC_SMD, &smdr);
return smdr & AT91_PMC_SMDS;
}
static int at91sam9x5_clk_smd_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct at91sam9x5_clk_smd *smd = to_at91sam9x5_clk_smd(hw);
unsigned long div = parent_rate / rate;
if (parent_rate % rate || div < 1 || div > (SMD_MAX_DIV + 1))
return -EINVAL;
regmap_update_bits(smd->regmap, AT91_PMC_SMD, AT91_PMC_SMD_DIV,
(div - 1) << SMD_DIV_SHIFT);
return 0;
}
static const struct clk_ops at91sam9x5_smd_ops = {
.recalc_rate = at91sam9x5_clk_smd_recalc_rate,
.round_rate = at91sam9x5_clk_smd_round_rate,
.get_parent = at91sam9x5_clk_smd_get_parent,
.set_parent = at91sam9x5_clk_smd_set_parent,
.set_rate = at91sam9x5_clk_smd_set_rate,
};
struct clk_hw * __init
at91sam9x5_clk_register_smd(struct regmap *regmap, const char *name,
const char **parent_names, u8 num_parents)
{
struct at91sam9x5_clk_smd *smd;
struct clk_hw *hw;
struct clk_init_data init;
int ret;
smd = kzalloc(sizeof(*smd), GFP_KERNEL);
if (!smd)
return ERR_PTR(-ENOMEM);
init.name = name;
init.ops = &at91sam9x5_smd_ops;
init.parent_names = parent_names;
init.num_parents = num_parents;
init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE;
smd->hw.init = &init;
smd->regmap = regmap;
hw = &smd->hw;
ret = clk_hw_register(NULL, &smd->hw);
if (ret) {
kfree(smd);
hw = ERR_PTR(ret);
}
return hw;
}