571 строка
12 KiB
C
571 строка
12 KiB
C
/*
|
|
* 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 = {
|
|
.resume_early = 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");
|