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linux/drivers/clk/clk-cs2000-cp.c
Nikita Yushchenko eade4ccdb0 clk: cs2000: set pm_ops in hibernate-compatible way 
Use SET_LATE_SYSTEM_SLEEP_PM_OPS() macro instead of direct assignment to
.resume_early field.

This fixes initialization of CS2000 in restore from hibernation in case
of kernel used to load image did not initialize CS2000 while kernel
being restored had CS2000 initialized.

Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2018-04-06 11:22:44 -07:00

571 lines
12 KiB
C
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/*
* CS2000 -- CIRRUS LOGIC Fractional-N Clock Synthesizer & Clock Multiplier
*
* Copyright (C) 2015 Renesas Electronics Corporation
* Kuninori Morimoto <kuninori.morimoto.gx@renesas.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.
*/
#include <linux/clk-provider.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/i2c.h>
#include <linux/of_device.h>
#include <linux/module.h>
#define CH_MAX 4
#define RATIO_REG_SIZE 4
#define DEVICE_ID 0x1
#define DEVICE_CTRL 0x2
#define DEVICE_CFG1 0x3
#define DEVICE_CFG2 0x4
#define GLOBAL_CFG 0x5
#define Ratio_Add(x, nth) (6 + (x * 4) + (nth))
#define Ratio_Val(x, nth) ((x >> (24 - (8 * nth))) & 0xFF)
#define Val_Ratio(x, nth) ((x & 0xFF) << (24 - (8 * nth)))
#define FUNC_CFG1 0x16
#define FUNC_CFG2 0x17
/* DEVICE_ID */
#define REVISION_MASK (0x7)
#define REVISION_B2_B3 (0x4)
#define REVISION_C1 (0x6)
/* DEVICE_CTRL */
#define PLL_UNLOCK (1 << 7)
#define AUXOUTDIS (1 << 1)
#define CLKOUTDIS (1 << 0)
/* DEVICE_CFG1 */
#define RSEL(x) (((x) & 0x3) << 3)
#define RSEL_MASK RSEL(0x3)
#define ENDEV1 (0x1)
/* DEVICE_CFG2 */
#define AUTORMOD (1 << 3)
#define LOCKCLK(x) (((x) & 0x3) << 1)
#define LOCKCLK_MASK LOCKCLK(0x3)
#define FRACNSRC_MASK (1 << 0)
#define FRACNSRC_STATIC (0 << 0)
#define FRACNSRC_DYNAMIC (1 << 1)
/* GLOBAL_CFG */
#define ENDEV2 (0x1)
/* FUNC_CFG1 */
#define CLKSKIPEN (1 << 7)
#define REFCLKDIV(x) (((x) & 0x3) << 3)
#define REFCLKDIV_MASK REFCLKDIV(0x3)
/* FUNC_CFG2 */
#define LFRATIO_MASK (1 << 3)
#define LFRATIO_20_12 (0 << 3)
#define LFRATIO_12_20 (1 << 3)
#define CH_SIZE_ERR(ch) ((ch < 0) || (ch >= CH_MAX))
#define hw_to_priv(_hw) container_of(_hw, struct cs2000_priv, hw)
#define priv_to_client(priv) (priv->client)
#define priv_to_dev(priv) (&(priv_to_client(priv)->dev))
#define CLK_IN 0
#define REF_CLK 1
#define CLK_MAX 2
struct cs2000_priv {
struct clk_hw hw;
struct i2c_client *client;
struct clk *clk_in;
struct clk *ref_clk;
/* suspend/resume */
unsigned long saved_rate;
unsigned long saved_parent_rate;
};
static const struct of_device_id cs2000_of_match[] = {
{ .compatible = "cirrus,cs2000-cp", },
{},
};
MODULE_DEVICE_TABLE(of, cs2000_of_match);
static const struct i2c_device_id cs2000_id[] = {
{ "cs2000-cp", },
{}
};
MODULE_DEVICE_TABLE(i2c, cs2000_id);
#define cs2000_read(priv, addr) \
i2c_smbus_read_byte_data(priv_to_client(priv), addr)
#define cs2000_write(priv, addr, val) \
i2c_smbus_write_byte_data(priv_to_client(priv), addr, val)
static int cs2000_bset(struct cs2000_priv *priv, u8 addr, u8 mask, u8 val)
{
s32 data;
data = cs2000_read(priv, addr);
if (data < 0)
return data;
data &= ~mask;
data |= (val & mask);
return cs2000_write(priv, addr, data);
}
static int cs2000_enable_dev_config(struct cs2000_priv *priv, bool enable)
{
int ret;
ret = cs2000_bset(priv, DEVICE_CFG1, ENDEV1,
enable ? ENDEV1 : 0);
if (ret < 0)
return ret;
ret = cs2000_bset(priv, GLOBAL_CFG, ENDEV2,
enable ? ENDEV2 : 0);
if (ret < 0)
return ret;
ret = cs2000_bset(priv, FUNC_CFG1, CLKSKIPEN,
enable ? CLKSKIPEN : 0);
if (ret < 0)
return ret;
/* FIXME: for Static ratio mode */
ret = cs2000_bset(priv, FUNC_CFG2, LFRATIO_MASK,
LFRATIO_12_20);
if (ret < 0)
return ret;
return 0;
}
static int cs2000_clk_in_bound_rate(struct cs2000_priv *priv,
u32 rate_in)
{
u32 val;
if (rate_in >= 32000000 && rate_in < 56000000)
val = 0x0;
else if (rate_in >= 16000000 && rate_in < 28000000)
val = 0x1;
else if (rate_in >= 8000000 && rate_in < 14000000)
val = 0x2;
else
return -EINVAL;
return cs2000_bset(priv, FUNC_CFG1,
REFCLKDIV_MASK,
REFCLKDIV(val));
}
static int cs2000_wait_pll_lock(struct cs2000_priv *priv)
{
struct device *dev = priv_to_dev(priv);
s32 val;
unsigned int i;
for (i = 0; i < 256; i++) {
val = cs2000_read(priv, DEVICE_CTRL);
if (val < 0)
return val;
if (!(val & PLL_UNLOCK))
return 0;
udelay(1);
}
dev_err(dev, "pll lock failed\n");
return -ETIMEDOUT;
}
static int cs2000_clk_out_enable(struct cs2000_priv *priv, bool enable)
{
/* enable both AUX_OUT, CLK_OUT */
return cs2000_bset(priv, DEVICE_CTRL,
(AUXOUTDIS | CLKOUTDIS),
enable ? 0 :
(AUXOUTDIS | CLKOUTDIS));
}
static u32 cs2000_rate_to_ratio(u32 rate_in, u32 rate_out)
{
u64 ratio;
/*
* ratio = rate_out / rate_in * 2^20
*
* To avoid over flow, rate_out is u64.
* The result should be u32.
*/
ratio = (u64)rate_out << 20;
do_div(ratio, rate_in);
return ratio;
}
static unsigned long cs2000_ratio_to_rate(u32 ratio, u32 rate_in)
{
u64 rate_out;
/*
* ratio = rate_out / rate_in * 2^20
*
* To avoid over flow, rate_out is u64.
* The result should be u32 or unsigned long.
*/
rate_out = (u64)ratio * rate_in;
return rate_out >> 20;
}
static int cs2000_ratio_set(struct cs2000_priv *priv,
int ch, u32 rate_in, u32 rate_out)
{
u32 val;
unsigned int i;
int ret;
if (CH_SIZE_ERR(ch))
return -EINVAL;
val = cs2000_rate_to_ratio(rate_in, rate_out);
for (i = 0; i < RATIO_REG_SIZE; i++) {
ret = cs2000_write(priv,
Ratio_Add(ch, i),
Ratio_Val(val, i));
if (ret < 0)
return ret;
}
return 0;
}
static u32 cs2000_ratio_get(struct cs2000_priv *priv, int ch)
{
s32 tmp;
u32 val;
unsigned int i;
val = 0;
for (i = 0; i < RATIO_REG_SIZE; i++) {
tmp = cs2000_read(priv, Ratio_Add(ch, i));
if (tmp < 0)
return 0;
val |= Val_Ratio(tmp, i);
}
return val;
}
static int cs2000_ratio_select(struct cs2000_priv *priv, int ch)
{
int ret;
if (CH_SIZE_ERR(ch))
return -EINVAL;
/*
* FIXME
*
* this driver supports static ratio mode only at this point.
*/
ret = cs2000_bset(priv, DEVICE_CFG1, RSEL_MASK, RSEL(ch));
if (ret < 0)
return ret;
ret = cs2000_bset(priv, DEVICE_CFG2,
(AUTORMOD | LOCKCLK_MASK | FRACNSRC_MASK),
(LOCKCLK(ch) | FRACNSRC_STATIC));
if (ret < 0)
return ret;
return 0;
}
static unsigned long cs2000_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct cs2000_priv *priv = hw_to_priv(hw);
int ch = 0; /* it uses ch0 only at this point */
u32 ratio;
ratio = cs2000_ratio_get(priv, ch);
return cs2000_ratio_to_rate(ratio, parent_rate);
}
static long cs2000_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *parent_rate)
{
u32 ratio;
ratio = cs2000_rate_to_ratio(*parent_rate, rate);
return cs2000_ratio_to_rate(ratio, *parent_rate);
}
static int __cs2000_set_rate(struct cs2000_priv *priv, int ch,
unsigned long rate, unsigned long parent_rate)
{
int ret;
ret = cs2000_clk_in_bound_rate(priv, parent_rate);
if (ret < 0)
return ret;
ret = cs2000_ratio_set(priv, ch, parent_rate, rate);
if (ret < 0)
return ret;
ret = cs2000_ratio_select(priv, ch);
if (ret < 0)
return ret;
priv->saved_rate = rate;
priv->saved_parent_rate = parent_rate;
return 0;
}
static int cs2000_set_rate(struct clk_hw *hw,
unsigned long rate, unsigned long parent_rate)
{
struct cs2000_priv *priv = hw_to_priv(hw);
int ch = 0; /* it uses ch0 only at this point */
return __cs2000_set_rate(priv, ch, rate, parent_rate);
}
static int cs2000_set_saved_rate(struct cs2000_priv *priv)
{
int ch = 0; /* it uses ch0 only at this point */
return __cs2000_set_rate(priv, ch,
priv->saved_rate,
priv->saved_parent_rate);
}
static int cs2000_enable(struct clk_hw *hw)
{
struct cs2000_priv *priv = hw_to_priv(hw);
int ret;
ret = cs2000_enable_dev_config(priv, true);
if (ret < 0)
return ret;
ret = cs2000_clk_out_enable(priv, true);
if (ret < 0)
return ret;
ret = cs2000_wait_pll_lock(priv);
if (ret < 0)
return ret;
return ret;
}
static void cs2000_disable(struct clk_hw *hw)
{
struct cs2000_priv *priv = hw_to_priv(hw);
cs2000_enable_dev_config(priv, false);
cs2000_clk_out_enable(priv, false);
}
static u8 cs2000_get_parent(struct clk_hw *hw)
{
/* always return REF_CLK */
return REF_CLK;
}
static const struct clk_ops cs2000_ops = {
.get_parent = cs2000_get_parent,
.recalc_rate = cs2000_recalc_rate,
.round_rate = cs2000_round_rate,
.set_rate = cs2000_set_rate,
.prepare = cs2000_enable,
.unprepare = cs2000_disable,
};
static int cs2000_clk_get(struct cs2000_priv *priv)
{
struct device *dev = priv_to_dev(priv);
struct clk *clk_in, *ref_clk;
clk_in = devm_clk_get(dev, "clk_in");
/* not yet provided */
if (IS_ERR(clk_in))
return -EPROBE_DEFER;
ref_clk = devm_clk_get(dev, "ref_clk");
/* not yet provided */
if (IS_ERR(ref_clk))
return -EPROBE_DEFER;
priv->clk_in = clk_in;
priv->ref_clk = ref_clk;
return 0;
}
static int cs2000_clk_register(struct cs2000_priv *priv)
{
struct device *dev = priv_to_dev(priv);
struct device_node *np = dev->of_node;
struct clk_init_data init;
const char *name = np->name;
static const char *parent_names[CLK_MAX];
int ch = 0; /* it uses ch0 only at this point */
int rate;
int ret;
of_property_read_string(np, "clock-output-names", &name);
/*
* set default rate as 1/1.
* otherwise .set_rate which setup ratio
* is never called if user requests 1/1 rate
*/
rate = clk_get_rate(priv->ref_clk);
ret = __cs2000_set_rate(priv, ch, rate, rate);
if (ret < 0)
return ret;
parent_names[CLK_IN] = __clk_get_name(priv->clk_in);
parent_names[REF_CLK] = __clk_get_name(priv->ref_clk);
init.name = name;
init.ops = &cs2000_ops;
init.flags = CLK_SET_RATE_GATE;
init.parent_names = parent_names;
init.num_parents = ARRAY_SIZE(parent_names);
priv->hw.init = &init;
ret = clk_hw_register(dev, &priv->hw);
if (ret)
return ret;
ret = of_clk_add_hw_provider(np, of_clk_hw_simple_get, &priv->hw);
if (ret < 0) {
clk_hw_unregister(&priv->hw);
return ret;
}
return 0;
}
static int cs2000_version_print(struct cs2000_priv *priv)
{
struct device *dev = priv_to_dev(priv);
s32 val;
const char *revision;
val = cs2000_read(priv, DEVICE_ID);
if (val < 0)
return val;
/* CS2000 should be 0x0 */
if (val >> 3)
return -EIO;
switch (val & REVISION_MASK) {
case REVISION_B2_B3:
revision = "B2 / B3";
break;
case REVISION_C1:
revision = "C1";
break;
default:
return -EIO;
}
dev_info(dev, "revision - %s\n", revision);
return 0;
}
static int cs2000_remove(struct i2c_client *client)
{
struct cs2000_priv *priv = i2c_get_clientdata(client);
struct device *dev = priv_to_dev(priv);
struct device_node *np = dev->of_node;
of_clk_del_provider(np);
clk_hw_unregister(&priv->hw);
return 0;
}
static int cs2000_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct cs2000_priv *priv;
struct device *dev = &client->dev;
int ret;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->client = client;
i2c_set_clientdata(client, priv);
ret = cs2000_clk_get(priv);
if (ret < 0)
return ret;
ret = cs2000_clk_register(priv);
if (ret < 0)
return ret;
ret = cs2000_version_print(priv);
if (ret < 0)
goto probe_err;
return 0;
probe_err:
cs2000_remove(client);
return ret;
}
static int cs2000_resume(struct device *dev)
{
struct cs2000_priv *priv = dev_get_drvdata(dev);
return cs2000_set_saved_rate(priv);
}
static const struct dev_pm_ops cs2000_pm_ops = {
SET_LATE_SYSTEM_SLEEP_PM_OPS(NULL, cs2000_resume)
};
static struct i2c_driver cs2000_driver = {
.driver = {
.name = "cs2000-cp",
.pm = &cs2000_pm_ops,
.of_match_table = cs2000_of_match,
},
.probe = cs2000_probe,
.remove = cs2000_remove,
.id_table = cs2000_id,
};
module_i2c_driver(cs2000_driver);
MODULE_DESCRIPTION("CS2000-CP driver");
MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
MODULE_LICENSE("GPL v2");
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