https://github.com/torvalds/linux
Tip revision: 0ecfebd2b52404ae0c54a878c872bb93363ada36 authored by Linus Torvalds on 07 July 2019, 22:41:56 UTC
Linux 5.2
Linux 5.2
Tip revision: 0ecfebd
i2s_pll_clock.c
/*
* Synopsys AXS10X SDP I2S PLL clock driver
*
* Copyright (C) 2016 Synopsys
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/clk-provider.h>
#include <linux/err.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/of_address.h>
#include <linux/slab.h>
#include <linux/of.h>
/* PLL registers addresses */
#define PLL_IDIV_REG 0x0
#define PLL_FBDIV_REG 0x4
#define PLL_ODIV0_REG 0x8
#define PLL_ODIV1_REG 0xC
struct i2s_pll_cfg {
unsigned int rate;
unsigned int idiv;
unsigned int fbdiv;
unsigned int odiv0;
unsigned int odiv1;
};
static const struct i2s_pll_cfg i2s_pll_cfg_27m[] = {
/* 27 Mhz */
{ 1024000, 0x104, 0x451, 0x10E38, 0x2000 },
{ 1411200, 0x104, 0x596, 0x10D35, 0x2000 },
{ 1536000, 0x208, 0xA28, 0x10B2C, 0x2000 },
{ 2048000, 0x82, 0x451, 0x10E38, 0x2000 },
{ 2822400, 0x82, 0x596, 0x10D35, 0x2000 },
{ 3072000, 0x104, 0xA28, 0x10B2C, 0x2000 },
{ 2116800, 0x82, 0x3CF, 0x10C30, 0x2000 },
{ 2304000, 0x104, 0x79E, 0x10B2C, 0x2000 },
{ 0, 0, 0, 0, 0 },
};
static const struct i2s_pll_cfg i2s_pll_cfg_28m[] = {
/* 28.224 Mhz */
{ 1024000, 0x82, 0x105, 0x107DF, 0x2000 },
{ 1411200, 0x28A, 0x1, 0x10001, 0x2000 },
{ 1536000, 0xA28, 0x187, 0x10042, 0x2000 },
{ 2048000, 0x41, 0x105, 0x107DF, 0x2000 },
{ 2822400, 0x145, 0x1, 0x10001, 0x2000 },
{ 3072000, 0x514, 0x187, 0x10042, 0x2000 },
{ 2116800, 0x514, 0x42, 0x10001, 0x2000 },
{ 2304000, 0x619, 0x82, 0x10001, 0x2000 },
{ 0, 0, 0, 0, 0 },
};
struct i2s_pll_clk {
void __iomem *base;
struct clk_hw hw;
struct device *dev;
};
static inline void i2s_pll_write(struct i2s_pll_clk *clk, unsigned int reg,
unsigned int val)
{
writel_relaxed(val, clk->base + reg);
}
static inline unsigned int i2s_pll_read(struct i2s_pll_clk *clk,
unsigned int reg)
{
return readl_relaxed(clk->base + reg);
}
static inline struct i2s_pll_clk *to_i2s_pll_clk(struct clk_hw *hw)
{
return container_of(hw, struct i2s_pll_clk, hw);
}
static inline unsigned int i2s_pll_get_value(unsigned int val)
{
return (val & 0x3F) + ((val >> 6) & 0x3F);
}
static const struct i2s_pll_cfg *i2s_pll_get_cfg(unsigned long prate)
{
switch (prate) {
case 27000000:
return i2s_pll_cfg_27m;
case 28224000:
return i2s_pll_cfg_28m;
default:
return NULL;
}
}
static unsigned long i2s_pll_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct i2s_pll_clk *clk = to_i2s_pll_clk(hw);
unsigned int idiv, fbdiv, odiv;
idiv = i2s_pll_get_value(i2s_pll_read(clk, PLL_IDIV_REG));
fbdiv = i2s_pll_get_value(i2s_pll_read(clk, PLL_FBDIV_REG));
odiv = i2s_pll_get_value(i2s_pll_read(clk, PLL_ODIV0_REG));
return ((parent_rate / idiv) * fbdiv) / odiv;
}
static long i2s_pll_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *prate)
{
struct i2s_pll_clk *clk = to_i2s_pll_clk(hw);
const struct i2s_pll_cfg *pll_cfg = i2s_pll_get_cfg(*prate);
int i;
if (!pll_cfg) {
dev_err(clk->dev, "invalid parent rate=%ld\n", *prate);
return -EINVAL;
}
for (i = 0; pll_cfg[i].rate != 0; i++)
if (pll_cfg[i].rate == rate)
return rate;
return -EINVAL;
}
static int i2s_pll_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct i2s_pll_clk *clk = to_i2s_pll_clk(hw);
const struct i2s_pll_cfg *pll_cfg = i2s_pll_get_cfg(parent_rate);
int i;
if (!pll_cfg) {
dev_err(clk->dev, "invalid parent rate=%ld\n", parent_rate);
return -EINVAL;
}
for (i = 0; pll_cfg[i].rate != 0; i++) {
if (pll_cfg[i].rate == rate) {
i2s_pll_write(clk, PLL_IDIV_REG, pll_cfg[i].idiv);
i2s_pll_write(clk, PLL_FBDIV_REG, pll_cfg[i].fbdiv);
i2s_pll_write(clk, PLL_ODIV0_REG, pll_cfg[i].odiv0);
i2s_pll_write(clk, PLL_ODIV1_REG, pll_cfg[i].odiv1);
return 0;
}
}
dev_err(clk->dev, "invalid rate=%ld, parent_rate=%ld\n", rate,
parent_rate);
return -EINVAL;
}
static const struct clk_ops i2s_pll_ops = {
.recalc_rate = i2s_pll_recalc_rate,
.round_rate = i2s_pll_round_rate,
.set_rate = i2s_pll_set_rate,
};
static int i2s_pll_clk_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *node = dev->of_node;
const char *clk_name;
const char *parent_name;
struct clk *clk;
struct i2s_pll_clk *pll_clk;
struct clk_init_data init;
struct resource *mem;
pll_clk = devm_kzalloc(dev, sizeof(*pll_clk), GFP_KERNEL);
if (!pll_clk)
return -ENOMEM;
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
pll_clk->base = devm_ioremap_resource(dev, mem);
if (IS_ERR(pll_clk->base))
return PTR_ERR(pll_clk->base);
memset(&init, 0, sizeof(init));
clk_name = node->name;
init.name = clk_name;
init.ops = &i2s_pll_ops;
parent_name = of_clk_get_parent_name(node, 0);
init.parent_names = &parent_name;
init.num_parents = 1;
pll_clk->hw.init = &init;
pll_clk->dev = dev;
clk = devm_clk_register(dev, &pll_clk->hw);
if (IS_ERR(clk)) {
dev_err(dev, "failed to register %s clock (%ld)\n",
clk_name, PTR_ERR(clk));
return PTR_ERR(clk);
}
return of_clk_add_provider(node, of_clk_src_simple_get, clk);
}
static int i2s_pll_clk_remove(struct platform_device *pdev)
{
of_clk_del_provider(pdev->dev.of_node);
return 0;
}
static const struct of_device_id i2s_pll_clk_id[] = {
{ .compatible = "snps,axs10x-i2s-pll-clock", },
{ },
};
MODULE_DEVICE_TABLE(of, i2s_pll_clk_id);
static struct platform_driver i2s_pll_clk_driver = {
.driver = {
.name = "axs10x-i2s-pll-clock",
.of_match_table = i2s_pll_clk_id,
},
.probe = i2s_pll_clk_probe,
.remove = i2s_pll_clk_remove,
};
module_platform_driver(i2s_pll_clk_driver);
MODULE_AUTHOR("Jose Abreu <joabreu@synopsys.com>");
MODULE_DESCRIPTION("Synopsys AXS10X SDP I2S PLL Clock Driver");
MODULE_LICENSE("GPL v2");