linux-stable/drivers/phy/samsung/phy-samsung-usb2.c
Marek Szyprowski 6aeec986f1 phy: samsung: disable bind/unbind platform driver feature
Samsung PHY drivers control the power to the SoC core components needed by
their client devices (USB HCDs, SATA, camera ISP bridge, DP encoder) to
properly operate. Disabling PHYs in runtime usually causes the client
device to crash with external abort exception or similar issue due to lack
of API to notify clients about PHY removal. This patch removes the
possiblity to unbind Samsung Exynos PHY drivers in runtime.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2019-08-23 09:40:59 +05:30

261 lines
6.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Samsung SoC USB 1.1/2.0 PHY driver
*
* Copyright (C) 2013 Samsung Electronics Co., Ltd.
* Author: Kamil Debski <k.debski@samsung.com>
*/
#include <linux/clk.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include "phy-samsung-usb2.h"
static int samsung_usb2_phy_power_on(struct phy *phy)
{
struct samsung_usb2_phy_instance *inst = phy_get_drvdata(phy);
struct samsung_usb2_phy_driver *drv = inst->drv;
int ret;
dev_dbg(drv->dev, "Request to power_on \"%s\" usb phy\n",
inst->cfg->label);
if (drv->vbus) {
ret = regulator_enable(drv->vbus);
if (ret)
goto err_regulator;
}
ret = clk_prepare_enable(drv->clk);
if (ret)
goto err_main_clk;
ret = clk_prepare_enable(drv->ref_clk);
if (ret)
goto err_instance_clk;
if (inst->cfg->power_on) {
spin_lock(&drv->lock);
ret = inst->cfg->power_on(inst);
spin_unlock(&drv->lock);
if (ret)
goto err_power_on;
}
return 0;
err_power_on:
clk_disable_unprepare(drv->ref_clk);
err_instance_clk:
clk_disable_unprepare(drv->clk);
err_main_clk:
if (drv->vbus)
regulator_disable(drv->vbus);
err_regulator:
return ret;
}
static int samsung_usb2_phy_power_off(struct phy *phy)
{
struct samsung_usb2_phy_instance *inst = phy_get_drvdata(phy);
struct samsung_usb2_phy_driver *drv = inst->drv;
int ret = 0;
dev_dbg(drv->dev, "Request to power_off \"%s\" usb phy\n",
inst->cfg->label);
if (inst->cfg->power_off) {
spin_lock(&drv->lock);
ret = inst->cfg->power_off(inst);
spin_unlock(&drv->lock);
if (ret)
return ret;
}
clk_disable_unprepare(drv->ref_clk);
clk_disable_unprepare(drv->clk);
if (drv->vbus)
ret = regulator_disable(drv->vbus);
return ret;
}
static const struct phy_ops samsung_usb2_phy_ops = {
.power_on = samsung_usb2_phy_power_on,
.power_off = samsung_usb2_phy_power_off,
.owner = THIS_MODULE,
};
static struct phy *samsung_usb2_phy_xlate(struct device *dev,
struct of_phandle_args *args)
{
struct samsung_usb2_phy_driver *drv;
drv = dev_get_drvdata(dev);
if (!drv)
return ERR_PTR(-EINVAL);
if (WARN_ON(args->args[0] >= drv->cfg->num_phys))
return ERR_PTR(-ENODEV);
return drv->instances[args->args[0]].phy;
}
static const struct of_device_id samsung_usb2_phy_of_match[] = {
#ifdef CONFIG_PHY_EXYNOS4X12_USB2
{
.compatible = "samsung,exynos3250-usb2-phy",
.data = &exynos3250_usb2_phy_config,
},
#endif
#ifdef CONFIG_PHY_EXYNOS4210_USB2
{
.compatible = "samsung,exynos4210-usb2-phy",
.data = &exynos4210_usb2_phy_config,
},
#endif
#ifdef CONFIG_PHY_EXYNOS4X12_USB2
{
.compatible = "samsung,exynos4x12-usb2-phy",
.data = &exynos4x12_usb2_phy_config,
},
#endif
#ifdef CONFIG_PHY_EXYNOS5250_USB2
{
.compatible = "samsung,exynos5250-usb2-phy",
.data = &exynos5250_usb2_phy_config,
},
#endif
#ifdef CONFIG_PHY_S5PV210_USB2
{
.compatible = "samsung,s5pv210-usb2-phy",
.data = &s5pv210_usb2_phy_config,
},
#endif
{ },
};
MODULE_DEVICE_TABLE(of, samsung_usb2_phy_of_match);
static int samsung_usb2_phy_probe(struct platform_device *pdev)
{
const struct samsung_usb2_phy_config *cfg;
struct device *dev = &pdev->dev;
struct phy_provider *phy_provider;
struct resource *mem;
struct samsung_usb2_phy_driver *drv;
int i, ret;
if (!pdev->dev.of_node) {
dev_err(dev, "This driver is required to be instantiated from device tree\n");
return -EINVAL;
}
cfg = of_device_get_match_data(dev);
if (!cfg)
return -EINVAL;
drv = devm_kzalloc(dev, struct_size(drv, instances, cfg->num_phys),
GFP_KERNEL);
if (!drv)
return -ENOMEM;
dev_set_drvdata(dev, drv);
spin_lock_init(&drv->lock);
drv->cfg = cfg;
drv->dev = dev;
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
drv->reg_phy = devm_ioremap_resource(dev, mem);
if (IS_ERR(drv->reg_phy)) {
dev_err(dev, "Failed to map register memory (phy)\n");
return PTR_ERR(drv->reg_phy);
}
drv->reg_pmu = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
"samsung,pmureg-phandle");
if (IS_ERR(drv->reg_pmu)) {
dev_err(dev, "Failed to map PMU registers (via syscon)\n");
return PTR_ERR(drv->reg_pmu);
}
if (drv->cfg->has_mode_switch) {
drv->reg_sys = syscon_regmap_lookup_by_phandle(
pdev->dev.of_node, "samsung,sysreg-phandle");
if (IS_ERR(drv->reg_sys)) {
dev_err(dev, "Failed to map system registers (via syscon)\n");
return PTR_ERR(drv->reg_sys);
}
}
drv->clk = devm_clk_get(dev, "phy");
if (IS_ERR(drv->clk)) {
dev_err(dev, "Failed to get clock of phy controller\n");
return PTR_ERR(drv->clk);
}
drv->ref_clk = devm_clk_get(dev, "ref");
if (IS_ERR(drv->ref_clk)) {
dev_err(dev, "Failed to get reference clock for the phy controller\n");
return PTR_ERR(drv->ref_clk);
}
drv->ref_rate = clk_get_rate(drv->ref_clk);
if (drv->cfg->rate_to_clk) {
ret = drv->cfg->rate_to_clk(drv->ref_rate, &drv->ref_reg_val);
if (ret)
return ret;
}
drv->vbus = devm_regulator_get(dev, "vbus");
if (IS_ERR(drv->vbus)) {
ret = PTR_ERR(drv->vbus);
if (ret == -EPROBE_DEFER)
return ret;
drv->vbus = NULL;
}
for (i = 0; i < drv->cfg->num_phys; i++) {
char *label = drv->cfg->phys[i].label;
struct samsung_usb2_phy_instance *p = &drv->instances[i];
dev_dbg(dev, "Creating phy \"%s\"\n", label);
p->phy = devm_phy_create(dev, NULL, &samsung_usb2_phy_ops);
if (IS_ERR(p->phy)) {
dev_err(drv->dev, "Failed to create usb2_phy \"%s\"\n",
label);
return PTR_ERR(p->phy);
}
p->cfg = &drv->cfg->phys[i];
p->drv = drv;
phy_set_bus_width(p->phy, 8);
phy_set_drvdata(p->phy, p);
}
phy_provider = devm_of_phy_provider_register(dev,
samsung_usb2_phy_xlate);
if (IS_ERR(phy_provider)) {
dev_err(drv->dev, "Failed to register phy provider\n");
return PTR_ERR(phy_provider);
}
return 0;
}
static struct platform_driver samsung_usb2_phy_driver = {
.probe = samsung_usb2_phy_probe,
.driver = {
.of_match_table = samsung_usb2_phy_of_match,
.name = "samsung-usb2-phy",
.suppress_bind_attrs = true,
}
};
module_platform_driver(samsung_usb2_phy_driver);
MODULE_DESCRIPTION("Samsung S5P/EXYNOS SoC USB PHY driver");
MODULE_AUTHOR("Kamil Debski <k.debski@samsung.com>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:samsung-usb2-phy");