linux_dsm_epyc7002/drivers/phy/qualcomm/phy-qcom-usb-hs.c
Stephan Gerhold 64f86b9978 phy: qcom-usb-hs: Fix extcon double register after power cycle
Commit f0b5c2c963 ("phy: qcom-usb-hs: Replace the extcon API")
switched from extcon_register_notifier() to the resource-managed
API, i.e. devm_extcon_register_notifier().

This is problematic in this case, because the extcon notifier
is dynamically registered/unregistered whenever the PHY is powered
on/off. The resource-managed API does not unregister the notifier
until the driver is removed, so as soon as the PHY is power cycled,
attempting to register the notifier again results in:

	double register detected
	WARNING: CPU: 1 PID: 182 at kernel/notifier.c:26 notifier_chain_register+0x74/0xa0
	Call trace:
	 ...
	 extcon_register_notifier+0x74/0xb8
	 devm_extcon_register_notifier+0x54/0xb8
	 qcom_usb_hs_phy_power_on+0x1fc/0x208
	 ...

... and USB stops working after plugging the cable out and in
another time.

The easiest way to fix this is to make a partial revert of
commit f0b5c2c963 ("phy: qcom-usb-hs: Replace the extcon API")
and avoid using the resource-managed API in this case.

Fixes: f0b5c2c963 ("phy: qcom-usb-hs: Replace the extcon API")
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2019-10-31 16:54:01 +05:30

290 lines
6.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/**
* Copyright (C) 2016 Linaro Ltd
*/
#include <linux/module.h>
#include <linux/ulpi/driver.h>
#include <linux/ulpi/regs.h>
#include <linux/clk.h>
#include <linux/regulator/consumer.h>
#include <linux/of_device.h>
#include <linux/phy/phy.h>
#include <linux/reset.h>
#include <linux/extcon.h>
#include <linux/notifier.h>
#define ULPI_PWR_CLK_MNG_REG 0x88
# define ULPI_PWR_OTG_COMP_DISABLE BIT(0)
#define ULPI_MISC_A 0x96
# define ULPI_MISC_A_VBUSVLDEXTSEL BIT(1)
# define ULPI_MISC_A_VBUSVLDEXT BIT(0)
struct ulpi_seq {
u8 addr;
u8 val;
};
struct qcom_usb_hs_phy {
struct ulpi *ulpi;
struct phy *phy;
struct clk *ref_clk;
struct clk *sleep_clk;
struct regulator *v1p8;
struct regulator *v3p3;
struct reset_control *reset;
struct ulpi_seq *init_seq;
struct extcon_dev *vbus_edev;
struct notifier_block vbus_notify;
};
static int qcom_usb_hs_phy_set_mode(struct phy *phy,
enum phy_mode mode, int submode)
{
struct qcom_usb_hs_phy *uphy = phy_get_drvdata(phy);
u8 addr;
int ret;
if (!uphy->vbus_edev) {
u8 val = 0;
switch (mode) {
case PHY_MODE_USB_OTG:
case PHY_MODE_USB_HOST:
val |= ULPI_INT_IDGRD;
/* fall through */
case PHY_MODE_USB_DEVICE:
val |= ULPI_INT_SESS_VALID;
default:
break;
}
ret = ulpi_write(uphy->ulpi, ULPI_USB_INT_EN_RISE, val);
if (ret)
return ret;
ret = ulpi_write(uphy->ulpi, ULPI_USB_INT_EN_FALL, val);
} else {
switch (mode) {
case PHY_MODE_USB_OTG:
case PHY_MODE_USB_DEVICE:
addr = ULPI_SET(ULPI_MISC_A);
break;
case PHY_MODE_USB_HOST:
addr = ULPI_CLR(ULPI_MISC_A);
break;
default:
return -EINVAL;
}
ret = ulpi_write(uphy->ulpi, ULPI_SET(ULPI_PWR_CLK_MNG_REG),
ULPI_PWR_OTG_COMP_DISABLE);
if (ret)
return ret;
ret = ulpi_write(uphy->ulpi, addr, ULPI_MISC_A_VBUSVLDEXTSEL);
}
return ret;
}
static int
qcom_usb_hs_phy_vbus_notifier(struct notifier_block *nb, unsigned long event,
void *ptr)
{
struct qcom_usb_hs_phy *uphy;
u8 addr;
uphy = container_of(nb, struct qcom_usb_hs_phy, vbus_notify);
if (event)
addr = ULPI_SET(ULPI_MISC_A);
else
addr = ULPI_CLR(ULPI_MISC_A);
return ulpi_write(uphy->ulpi, addr, ULPI_MISC_A_VBUSVLDEXT);
}
static int qcom_usb_hs_phy_power_on(struct phy *phy)
{
struct qcom_usb_hs_phy *uphy = phy_get_drvdata(phy);
struct ulpi *ulpi = uphy->ulpi;
const struct ulpi_seq *seq;
int ret, state;
ret = clk_prepare_enable(uphy->ref_clk);
if (ret)
return ret;
ret = clk_prepare_enable(uphy->sleep_clk);
if (ret)
goto err_sleep;
ret = regulator_set_load(uphy->v1p8, 50000);
if (ret < 0)
goto err_1p8;
ret = regulator_enable(uphy->v1p8);
if (ret)
goto err_1p8;
ret = regulator_set_voltage_triplet(uphy->v3p3, 3050000, 3300000,
3300000);
if (ret)
goto err_3p3;
ret = regulator_set_load(uphy->v3p3, 50000);
if (ret < 0)
goto err_3p3;
ret = regulator_enable(uphy->v3p3);
if (ret)
goto err_3p3;
for (seq = uphy->init_seq; seq->addr; seq++) {
ret = ulpi_write(ulpi, ULPI_EXT_VENDOR_SPECIFIC + seq->addr,
seq->val);
if (ret)
goto err_ulpi;
}
if (uphy->reset) {
ret = reset_control_reset(uphy->reset);
if (ret)
goto err_ulpi;
}
if (uphy->vbus_edev) {
state = extcon_get_state(uphy->vbus_edev, EXTCON_USB);
/* setup initial state */
qcom_usb_hs_phy_vbus_notifier(&uphy->vbus_notify, state,
uphy->vbus_edev);
ret = extcon_register_notifier(uphy->vbus_edev, EXTCON_USB,
&uphy->vbus_notify);
if (ret)
goto err_ulpi;
}
return 0;
err_ulpi:
regulator_disable(uphy->v3p3);
err_3p3:
regulator_disable(uphy->v1p8);
err_1p8:
clk_disable_unprepare(uphy->sleep_clk);
err_sleep:
clk_disable_unprepare(uphy->ref_clk);
return ret;
}
static int qcom_usb_hs_phy_power_off(struct phy *phy)
{
struct qcom_usb_hs_phy *uphy = phy_get_drvdata(phy);
if (uphy->vbus_edev)
extcon_unregister_notifier(uphy->vbus_edev, EXTCON_USB,
&uphy->vbus_notify);
regulator_disable(uphy->v3p3);
regulator_disable(uphy->v1p8);
clk_disable_unprepare(uphy->sleep_clk);
clk_disable_unprepare(uphy->ref_clk);
return 0;
}
static const struct phy_ops qcom_usb_hs_phy_ops = {
.power_on = qcom_usb_hs_phy_power_on,
.power_off = qcom_usb_hs_phy_power_off,
.set_mode = qcom_usb_hs_phy_set_mode,
.owner = THIS_MODULE,
};
static int qcom_usb_hs_phy_probe(struct ulpi *ulpi)
{
struct qcom_usb_hs_phy *uphy;
struct phy_provider *p;
struct clk *clk;
struct regulator *reg;
struct reset_control *reset;
int size;
int ret;
uphy = devm_kzalloc(&ulpi->dev, sizeof(*uphy), GFP_KERNEL);
if (!uphy)
return -ENOMEM;
ulpi_set_drvdata(ulpi, uphy);
uphy->ulpi = ulpi;
size = of_property_count_u8_elems(ulpi->dev.of_node, "qcom,init-seq");
if (size < 0)
size = 0;
uphy->init_seq = devm_kmalloc_array(&ulpi->dev, (size / 2) + 1,
sizeof(*uphy->init_seq), GFP_KERNEL);
if (!uphy->init_seq)
return -ENOMEM;
ret = of_property_read_u8_array(ulpi->dev.of_node, "qcom,init-seq",
(u8 *)uphy->init_seq, size);
if (ret && size)
return ret;
/* NUL terminate */
uphy->init_seq[size / 2].addr = uphy->init_seq[size / 2].val = 0;
uphy->ref_clk = clk = devm_clk_get(&ulpi->dev, "ref");
if (IS_ERR(clk))
return PTR_ERR(clk);
uphy->sleep_clk = clk = devm_clk_get(&ulpi->dev, "sleep");
if (IS_ERR(clk))
return PTR_ERR(clk);
uphy->v1p8 = reg = devm_regulator_get(&ulpi->dev, "v1p8");
if (IS_ERR(reg))
return PTR_ERR(reg);
uphy->v3p3 = reg = devm_regulator_get(&ulpi->dev, "v3p3");
if (IS_ERR(reg))
return PTR_ERR(reg);
uphy->reset = reset = devm_reset_control_get(&ulpi->dev, "por");
if (IS_ERR(reset)) {
if (PTR_ERR(reset) == -EPROBE_DEFER)
return PTR_ERR(reset);
uphy->reset = NULL;
}
uphy->phy = devm_phy_create(&ulpi->dev, ulpi->dev.of_node,
&qcom_usb_hs_phy_ops);
if (IS_ERR(uphy->phy))
return PTR_ERR(uphy->phy);
uphy->vbus_edev = extcon_get_edev_by_phandle(&ulpi->dev, 0);
if (IS_ERR(uphy->vbus_edev)) {
if (PTR_ERR(uphy->vbus_edev) != -ENODEV)
return PTR_ERR(uphy->vbus_edev);
uphy->vbus_edev = NULL;
}
uphy->vbus_notify.notifier_call = qcom_usb_hs_phy_vbus_notifier;
phy_set_drvdata(uphy->phy, uphy);
p = devm_of_phy_provider_register(&ulpi->dev, of_phy_simple_xlate);
return PTR_ERR_OR_ZERO(p);
}
static const struct of_device_id qcom_usb_hs_phy_match[] = {
{ .compatible = "qcom,usb-hs-phy", },
{ }
};
MODULE_DEVICE_TABLE(of, qcom_usb_hs_phy_match);
static struct ulpi_driver qcom_usb_hs_phy_driver = {
.probe = qcom_usb_hs_phy_probe,
.driver = {
.name = "qcom_usb_hs_phy",
.of_match_table = qcom_usb_hs_phy_match,
},
};
module_ulpi_driver(qcom_usb_hs_phy_driver);
MODULE_DESCRIPTION("Qualcomm USB HS phy");
MODULE_LICENSE("GPL v2");