linux/drivers/phy/st/phy-stm32-usbphyc.c
Amelie Delaunay 52113be1c6 phy: stm32: fix usbphyc static checker and checkpatch warnings
This patch fixes the following issues:
* warning reported by checkpatch:
WARNING: line over 80 characters
#87: FILE: drivers/phy/st/phy-stm32-usbphyc.c:87:
+static void stm32_usbphyc_get_pll_params(u32 clk_rate, struct pll_params *pll_params)

* bug reported by static checker (Dan Carpenter):
drivers/phy/st/phy-stm32-usbphyc.c:371 stm32_usbphyc_probe()
error: uninitialized symbol 'i'.

* unused stm32_usbphyc structure member: bool pll_enabled.

* unnecessary extra line in stm32_usbphyc_of_xlate

Fixes: 94c358da3a "phy: stm32: add support for STM32 USB PHY Controller (USBPHYC)"
Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2018-05-20 21:51:25 +05:30

461 lines
11 KiB
C

// SPDX-Licence-Identifier: GPL-2.0
/*
* STMicroelectronics STM32 USB PHY Controller driver
*
* Copyright (C) 2018 STMicroelectronics
* Author(s): Amelie Delaunay <amelie.delaunay@st.com>.
*/
#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/phy/phy.h>
#include <linux/reset.h>
#define STM32_USBPHYC_PLL 0x0
#define STM32_USBPHYC_MISC 0x8
#define STM32_USBPHYC_VERSION 0x3F4
/* STM32_USBPHYC_PLL bit fields */
#define PLLNDIV GENMASK(6, 0)
#define PLLFRACIN GENMASK(25, 10)
#define PLLEN BIT(26)
#define PLLSTRB BIT(27)
#define PLLSTRBYP BIT(28)
#define PLLFRACCTL BIT(29)
#define PLLDITHEN0 BIT(30)
#define PLLDITHEN1 BIT(31)
/* STM32_USBPHYC_MISC bit fields */
#define SWITHOST BIT(0)
/* STM32_USBPHYC_VERSION bit fields */
#define MINREV GENMASK(3, 0)
#define MAJREV GENMASK(7, 4)
static const char * const supplies_names[] = {
"vdda1v1", /* 1V1 */
"vdda1v8", /* 1V8 */
};
#define NUM_SUPPLIES ARRAY_SIZE(supplies_names)
#define PLL_LOCK_TIME_US 100
#define PLL_PWR_DOWN_TIME_US 5
#define PLL_FVCO_MHZ 2880
#define PLL_INFF_MIN_RATE_HZ 19200000
#define PLL_INFF_MAX_RATE_HZ 38400000
#define HZ_PER_MHZ 1000000L
struct pll_params {
u8 ndiv;
u16 frac;
};
struct stm32_usbphyc_phy {
struct phy *phy;
struct stm32_usbphyc *usbphyc;
struct regulator_bulk_data supplies[NUM_SUPPLIES];
u32 index;
bool active;
};
struct stm32_usbphyc {
struct device *dev;
void __iomem *base;
struct clk *clk;
struct reset_control *rst;
struct stm32_usbphyc_phy **phys;
int nphys;
int switch_setup;
};
static inline void stm32_usbphyc_set_bits(void __iomem *reg, u32 bits)
{
writel_relaxed(readl_relaxed(reg) | bits, reg);
}
static inline void stm32_usbphyc_clr_bits(void __iomem *reg, u32 bits)
{
writel_relaxed(readl_relaxed(reg) & ~bits, reg);
}
static void stm32_usbphyc_get_pll_params(u32 clk_rate,
struct pll_params *pll_params)
{
unsigned long long fvco, ndiv, frac;
/* _
* | FVCO = INFF*2*(NDIV + FRACT/2^16) when DITHER_DISABLE[1] = 1
* | FVCO = 2880MHz
* <
* | NDIV = integer part of input bits to set the LDF
* |_FRACT = fractional part of input bits to set the LDF
* => PLLNDIV = integer part of (FVCO / (INFF*2))
* => PLLFRACIN = fractional part of(FVCO / INFF*2) * 2^16
* <=> PLLFRACIN = ((FVCO / (INFF*2)) - PLLNDIV) * 2^16
*/
fvco = (unsigned long long)PLL_FVCO_MHZ * HZ_PER_MHZ;
ndiv = fvco;
do_div(ndiv, (clk_rate * 2));
pll_params->ndiv = (u8)ndiv;
frac = fvco * (1 << 16);
do_div(frac, (clk_rate * 2));
frac = frac - (ndiv * (1 << 16));
pll_params->frac = (u16)frac;
}
static int stm32_usbphyc_pll_init(struct stm32_usbphyc *usbphyc)
{
struct pll_params pll_params;
u32 clk_rate = clk_get_rate(usbphyc->clk);
u32 ndiv, frac;
u32 usbphyc_pll;
if ((clk_rate < PLL_INFF_MIN_RATE_HZ) ||
(clk_rate > PLL_INFF_MAX_RATE_HZ)) {
dev_err(usbphyc->dev, "input clk freq (%dHz) out of range\n",
clk_rate);
return -EINVAL;
}
stm32_usbphyc_get_pll_params(clk_rate, &pll_params);
ndiv = FIELD_PREP(PLLNDIV, pll_params.ndiv);
frac = FIELD_PREP(PLLFRACIN, pll_params.frac);
usbphyc_pll = PLLDITHEN1 | PLLDITHEN0 | PLLSTRBYP | ndiv;
if (pll_params.frac)
usbphyc_pll |= PLLFRACCTL | frac;
writel_relaxed(usbphyc_pll, usbphyc->base + STM32_USBPHYC_PLL);
dev_dbg(usbphyc->dev, "input clk freq=%dHz, ndiv=%lu, frac=%lu\n",
clk_rate, FIELD_GET(PLLNDIV, usbphyc_pll),
FIELD_GET(PLLFRACIN, usbphyc_pll));
return 0;
}
static bool stm32_usbphyc_has_one_phy_active(struct stm32_usbphyc *usbphyc)
{
int i;
for (i = 0; i < usbphyc->nphys; i++)
if (usbphyc->phys[i]->active)
return true;
return false;
}
static int stm32_usbphyc_pll_enable(struct stm32_usbphyc *usbphyc)
{
void __iomem *pll_reg = usbphyc->base + STM32_USBPHYC_PLL;
bool pllen = (readl_relaxed(pll_reg) & PLLEN);
int ret;
/* Check if one phy port has already configured the pll */
if (pllen && stm32_usbphyc_has_one_phy_active(usbphyc))
return 0;
if (pllen) {
stm32_usbphyc_clr_bits(pll_reg, PLLEN);
/* Wait for minimum width of powerdown pulse (ENABLE = Low) */
udelay(PLL_PWR_DOWN_TIME_US);
}
ret = stm32_usbphyc_pll_init(usbphyc);
if (ret)
return ret;
stm32_usbphyc_set_bits(pll_reg, PLLEN);
/* Wait for maximum lock time */
udelay(PLL_LOCK_TIME_US);
if (!(readl_relaxed(pll_reg) & PLLEN)) {
dev_err(usbphyc->dev, "PLLEN not set\n");
return -EIO;
}
return 0;
}
static int stm32_usbphyc_pll_disable(struct stm32_usbphyc *usbphyc)
{
void __iomem *pll_reg = usbphyc->base + STM32_USBPHYC_PLL;
/* Check if other phy port active */
if (stm32_usbphyc_has_one_phy_active(usbphyc))
return 0;
stm32_usbphyc_clr_bits(pll_reg, PLLEN);
/* Wait for minimum width of powerdown pulse (ENABLE = Low) */
udelay(PLL_PWR_DOWN_TIME_US);
if (readl_relaxed(pll_reg) & PLLEN) {
dev_err(usbphyc->dev, "PLL not reset\n");
return -EIO;
}
return 0;
}
static int stm32_usbphyc_phy_init(struct phy *phy)
{
struct stm32_usbphyc_phy *usbphyc_phy = phy_get_drvdata(phy);
struct stm32_usbphyc *usbphyc = usbphyc_phy->usbphyc;
int ret;
ret = stm32_usbphyc_pll_enable(usbphyc);
if (ret)
return ret;
usbphyc_phy->active = true;
return 0;
}
static int stm32_usbphyc_phy_exit(struct phy *phy)
{
struct stm32_usbphyc_phy *usbphyc_phy = phy_get_drvdata(phy);
struct stm32_usbphyc *usbphyc = usbphyc_phy->usbphyc;
usbphyc_phy->active = false;
return stm32_usbphyc_pll_disable(usbphyc);
}
static int stm32_usbphyc_phy_power_on(struct phy *phy)
{
struct stm32_usbphyc_phy *usbphyc_phy = phy_get_drvdata(phy);
return regulator_bulk_enable(NUM_SUPPLIES, usbphyc_phy->supplies);
}
static int stm32_usbphyc_phy_power_off(struct phy *phy)
{
struct stm32_usbphyc_phy *usbphyc_phy = phy_get_drvdata(phy);
return regulator_bulk_disable(NUM_SUPPLIES, usbphyc_phy->supplies);
}
static const struct phy_ops stm32_usbphyc_phy_ops = {
.init = stm32_usbphyc_phy_init,
.exit = stm32_usbphyc_phy_exit,
.power_on = stm32_usbphyc_phy_power_on,
.power_off = stm32_usbphyc_phy_power_off,
.owner = THIS_MODULE,
};
static void stm32_usbphyc_switch_setup(struct stm32_usbphyc *usbphyc,
u32 utmi_switch)
{
if (!utmi_switch)
stm32_usbphyc_clr_bits(usbphyc->base + STM32_USBPHYC_MISC,
SWITHOST);
else
stm32_usbphyc_set_bits(usbphyc->base + STM32_USBPHYC_MISC,
SWITHOST);
usbphyc->switch_setup = utmi_switch;
}
static struct phy *stm32_usbphyc_of_xlate(struct device *dev,
struct of_phandle_args *args)
{
struct stm32_usbphyc *usbphyc = dev_get_drvdata(dev);
struct stm32_usbphyc_phy *usbphyc_phy = NULL;
struct device_node *phynode = args->np;
int port = 0;
for (port = 0; port < usbphyc->nphys; port++) {
if (phynode == usbphyc->phys[port]->phy->dev.of_node) {
usbphyc_phy = usbphyc->phys[port];
break;
}
}
if (!usbphyc_phy) {
dev_err(dev, "failed to find phy\n");
return ERR_PTR(-EINVAL);
}
if (((usbphyc_phy->index == 0) && (args->args_count != 0)) ||
((usbphyc_phy->index == 1) && (args->args_count != 1))) {
dev_err(dev, "invalid number of cells for phy port%d\n",
usbphyc_phy->index);
return ERR_PTR(-EINVAL);
}
/* Configure the UTMI switch for PHY port#2 */
if (usbphyc_phy->index == 1) {
if (usbphyc->switch_setup < 0) {
stm32_usbphyc_switch_setup(usbphyc, args->args[0]);
} else {
if (args->args[0] != usbphyc->switch_setup) {
dev_err(dev, "phy port1 already used\n");
return ERR_PTR(-EBUSY);
}
}
}
return usbphyc_phy->phy;
}
static int stm32_usbphyc_probe(struct platform_device *pdev)
{
struct stm32_usbphyc *usbphyc;
struct device *dev = &pdev->dev;
struct device_node *child, *np = dev->of_node;
struct resource *res;
struct phy_provider *phy_provider;
u32 version;
int ret, port = 0;
usbphyc = devm_kzalloc(dev, sizeof(*usbphyc), GFP_KERNEL);
if (!usbphyc)
return -ENOMEM;
usbphyc->dev = dev;
dev_set_drvdata(dev, usbphyc);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
usbphyc->base = devm_ioremap_resource(dev, res);
if (IS_ERR(usbphyc->base))
return PTR_ERR(usbphyc->base);
usbphyc->clk = devm_clk_get(dev, 0);
if (IS_ERR(usbphyc->clk)) {
ret = PTR_ERR(usbphyc->clk);
dev_err(dev, "clk get failed: %d\n", ret);
return ret;
}
ret = clk_prepare_enable(usbphyc->clk);
if (ret) {
dev_err(dev, "clk enable failed: %d\n", ret);
return ret;
}
usbphyc->rst = devm_reset_control_get(dev, 0);
if (!IS_ERR(usbphyc->rst)) {
reset_control_assert(usbphyc->rst);
udelay(2);
reset_control_deassert(usbphyc->rst);
}
usbphyc->switch_setup = -EINVAL;
usbphyc->nphys = of_get_child_count(np);
usbphyc->phys = devm_kcalloc(dev, usbphyc->nphys,
sizeof(*usbphyc->phys), GFP_KERNEL);
if (!usbphyc->phys) {
ret = -ENOMEM;
goto clk_disable;
}
for_each_child_of_node(np, child) {
struct stm32_usbphyc_phy *usbphyc_phy;
struct phy *phy;
u32 index;
int i;
phy = devm_phy_create(dev, child, &stm32_usbphyc_phy_ops);
if (IS_ERR(phy)) {
ret = PTR_ERR(phy);
if (ret != -EPROBE_DEFER)
dev_err(dev, "failed to create phy%d: %d\n",
port, ret);
goto put_child;
}
usbphyc_phy = devm_kzalloc(dev, sizeof(*usbphyc_phy),
GFP_KERNEL);
if (!usbphyc_phy) {
ret = -ENOMEM;
goto put_child;
}
for (i = 0; i < NUM_SUPPLIES; i++)
usbphyc_phy->supplies[i].supply = supplies_names[i];
ret = devm_regulator_bulk_get(&phy->dev, NUM_SUPPLIES,
usbphyc_phy->supplies);
if (ret) {
if (ret != -EPROBE_DEFER)
dev_err(&phy->dev,
"failed to get regulators: %d\n", ret);
goto put_child;
}
ret = of_property_read_u32(child, "reg", &index);
if (ret || index > usbphyc->nphys) {
dev_err(&phy->dev, "invalid reg property: %d\n", ret);
goto put_child;
}
usbphyc->phys[port] = usbphyc_phy;
phy_set_bus_width(phy, 8);
phy_set_drvdata(phy, usbphyc_phy);
usbphyc->phys[port]->phy = phy;
usbphyc->phys[port]->usbphyc = usbphyc;
usbphyc->phys[port]->index = index;
usbphyc->phys[port]->active = false;
port++;
}
phy_provider = devm_of_phy_provider_register(dev,
stm32_usbphyc_of_xlate);
if (IS_ERR(phy_provider)) {
ret = PTR_ERR(phy_provider);
dev_err(dev, "failed to register phy provider: %d\n", ret);
goto clk_disable;
}
version = readl_relaxed(usbphyc->base + STM32_USBPHYC_VERSION);
dev_info(dev, "registered rev:%lu.%lu\n",
FIELD_GET(MAJREV, version), FIELD_GET(MINREV, version));
return 0;
put_child:
of_node_put(child);
clk_disable:
clk_disable_unprepare(usbphyc->clk);
return ret;
}
static int stm32_usbphyc_remove(struct platform_device *pdev)
{
struct stm32_usbphyc *usbphyc = dev_get_drvdata(&pdev->dev);
clk_disable_unprepare(usbphyc->clk);
return 0;
}
static const struct of_device_id stm32_usbphyc_of_match[] = {
{ .compatible = "st,stm32mp1-usbphyc", },
{ },
};
MODULE_DEVICE_TABLE(of, stm32_usbphyc_of_match);
static struct platform_driver stm32_usbphyc_driver = {
.probe = stm32_usbphyc_probe,
.remove = stm32_usbphyc_remove,
.driver = {
.of_match_table = stm32_usbphyc_of_match,
.name = "stm32-usbphyc",
}
};
module_platform_driver(stm32_usbphyc_driver);
MODULE_DESCRIPTION("STMicroelectronics STM32 USBPHYC driver");
MODULE_AUTHOR("Amelie Delaunay <amelie.delaunay@st.com>");
MODULE_LICENSE("GPL v2");