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extcon: Add LC824206XA microUSB switch driver

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Add a new driver for the ON Semiconductor LC824206XA microUSB switch and
accessory detector chip.

ON Semiconductor has an "Advance Information" datasheet available
(ENA2222-D.PDF), but no full datasheet. So there is no documentation
available for the registers.

This driver is based on the register info from the extcon-fsa9285.c driver,
from the Lollipop Android sources for the Lenovo Yoga Tablet 2 (Pro)
830 / 1050 / 1380 models. Note despite the name this is actually a driver
for the LC824206XA not the FSA9285.

This has only been tested on a Lenovo Yoga Tablet 2 Pro 1380 and
using the driver on other setups may require additional work.

So far this driver is only used on x86/ACPI (non devicetree) devs.
Therefor there is no devicetree bindings documentation for this driver's
"onnn,enable-miclr-for-dcp" property since this is not used in actual
devicetree files and the dt bindings maintainers have requested properties
with no actual dt users to _not_ be added to the dt bindings.

Link: https://lore.kernel.org/lkml/20240512204019.58121-1-hdegoede@redhat.com/
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
This commit is contained in:
Hans de Goede 2024-05-12 22:40:19 +02:00 committed by Chanwoo Choi
parent 47ac09b91b
commit 9e1897cb95
3 changed files with 512 additions and 0 deletions
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11
drivers/extcon/Kconfig
View File

@ -75,6 +75,17 @@ config EXTCON_INTEL_MRFLD
Say Y here to enable extcon support for charger detection / control
on the Intel Merrifield Basin Cove PMIC.
config EXTCON_LC824206XA
tristate "LC824206XA extcon Support"
depends on I2C
depends on POWER_SUPPLY
help
Say Y here to enable support for the ON Semiconductor LC824206XA
microUSB switch and accessory detector chip. The LC824206XA is a USB
port accessory detector and switch. The LC824206XA is fully controlled
using I2C and enables USB data, stereo and mono audio, video,
microphone and UART data to use a common connector port.
config EXTCON_MAX14577
tristate "Maxim MAX14577/77836 EXTCON Support"
depends on MFD_MAX14577

1
drivers/extcon/Makefile
View File

@ -12,6 +12,7 @@ obj-$(CONFIG_EXTCON_GPIO) += extcon-gpio.o
obj-$(CONFIG_EXTCON_INTEL_INT3496) += extcon-intel-int3496.o
obj-$(CONFIG_EXTCON_INTEL_CHT_WC) += extcon-intel-cht-wc.o
obj-$(CONFIG_EXTCON_INTEL_MRFLD) += extcon-intel-mrfld.o
obj-$(CONFIG_EXTCON_LC824206XA) += extcon-lc824206xa.o
obj-$(CONFIG_EXTCON_MAX14577) += extcon-max14577.o
obj-$(CONFIG_EXTCON_MAX3355) += extcon-max3355.o
obj-$(CONFIG_EXTCON_MAX77693) += extcon-max77693.o

500
drivers/extcon/extcon-lc824206xa.c Normal file
View File

@ -0,0 +1,500 @@
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* ON Semiconductor LC824206XA Micro USB Switch driver
*
* Copyright (c) 2024 Hans de Goede <hansg@kernel.org>
*
* ON Semiconductor has an "Advance Information" datasheet available
* (ENA2222-D.PDF), but no full datasheet. So there is no documentation
* available for the registers.
*
* This driver is based on the register info from the extcon-fsa9285.c driver,
* from the Lollipop Android sources for the Lenovo Yoga Tablet 2 (Pro)
* 830 / 1050 / 1380 models. Note despite the name this is actually a driver
* for the LC824206XA not the FSA9285. The Android sources can be downloaded
* from Lenovo's support page for these tablets, filename:
* yoga_tab_2_osc_android_to_lollipop_201505.rar.
*/
#include <linux/bits.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/extcon-provider.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/power_supply.h>
#include <linux/property.h>
#include <linux/regulator/consumer.h>
#include <linux/workqueue.h>
/*
* Register defines as mentioned above there is no datasheet with register
* info, so this may not be 100% accurate.
*/
#define REG00 0x00
#define REG00_INIT_VALUE 0x01
#define REG_STATUS 0x01
#define STATUS_OVP BIT(0)
#define STATUS_DATA_SHORT BIT(1)
#define STATUS_VBUS_PRESENT BIT(2)
#define STATUS_USB_ID GENMASK(7, 3)
#define STATUS_USB_ID_GND 0x80
#define STATUS_USB_ID_ACA 0xf0
#define STATUS_USB_ID_FLOAT 0xf8
/*
* This controls the DP/DM muxes + other switches,
* meaning of individual bits is unknown.
*/
#define REG_SWITCH_CONTROL 0x02
#define SWITCH_STEREO_MIC 0xc8
#define SWITCH_USB_HOST 0xec
#define SWITCH_DISCONNECTED 0xf8
#define SWITCH_USB_DEVICE 0xfc
/* 5 bits? ADC 0x10 GND, 0x1a-0x1f ACA, 0x1f float */
#define REG_ID_PIN_ADC_VALUE 0x03
/* Masks for all 3 interrupt registers */
#define INTR_ID_PIN_CHANGE BIT(0)
#define INTR_VBUS_CHANGE BIT(1)
/* Both of these get set after a continuous mode ADC conversion */
#define INTR_ID_PIN_ADC_INT1 BIT(2)
#define INTR_ID_PIN_ADC_INT2 BIT(3)
/* Charger type available in reg 0x09 */
#define INTR_CHARGER_DET_DONE BIT(4)
#define INTR_OVP BIT(5)
/* There are 7 interrupt sources, bit 6 use is unknown (OCP?) */
#define INTR_ALL GENMASK(6, 0)
/* Unmask interrupts this driver cares about */
#define INTR_MASK \
(INTR_ALL & ~(INTR_ID_PIN_CHANGE | INTR_VBUS_CHANGE | INTR_CHARGER_DET_DONE))
/* Active (event happened and not cleared yet) interrupts */
#define REG_INTR_STATUS 0x04
/*
* Writing a 1 to a bit here clears it in INTR_STATUS. These bits do NOT
* auto-reset to 0, so these must be set to 0 manually after clearing.
*/
#define REG_INTR_CLEAR 0x05
/* Interrupts which bit is set to 1 here will not raise the HW IRQ */
#define REG_INTR_MASK 0x06
/* ID pin ADC control, meaning of individual bits is unknown */
#define REG_ID_PIN_ADC_CTRL 0x07
#define ID_PIN_ADC_AUTO 0x40
#define ID_PIN_ADC_CONTINUOUS 0x44
#define REG_CHARGER_DET 0x08
#define CHARGER_DET_ON BIT(0)
#define CHARGER_DET_CDP_ON BIT(1)
#define CHARGER_DET_CDP_VAL BIT(2)
#define REG_CHARGER_TYPE 0x09
#define CHARGER_TYPE_UNKNOWN 0x00
#define CHARGER_TYPE_DCP 0x01
#define CHARGER_TYPE_SDP_OR_CDP 0x04
#define CHARGER_TYPE_QC 0x06
#define REG10 0x10
#define REG10_INIT_VALUE 0x00
struct lc824206xa_data {
struct work_struct work;
struct i2c_client *client;
struct extcon_dev *edev;
struct power_supply *psy;
struct regulator *vbus_boost;
unsigned int usb_type;
unsigned int cable;
unsigned int previous_cable;
u8 switch_control;
u8 previous_switch_control;
bool vbus_ok;
bool vbus_boost_enabled;
bool fastcharge_over_miclr;
};
static const unsigned int lc824206xa_cables[] = {
EXTCON_USB_HOST,
EXTCON_CHG_USB_SDP,
EXTCON_CHG_USB_CDP,
EXTCON_CHG_USB_DCP,
EXTCON_CHG_USB_ACA,
EXTCON_CHG_USB_FAST,
EXTCON_NONE,
};
/* read/write reg helpers to add error logging to smbus byte functions */
static int lc824206xa_read_reg(struct lc824206xa_data *data, u8 reg)
{
int ret;
ret = i2c_smbus_read_byte_data(data->client, reg);
if (ret < 0)
dev_err(&data->client->dev, "Error %d reading reg 0x%02x\n", ret, reg);
return ret;
}
static int lc824206xa_write_reg(struct lc824206xa_data *data, u8 reg, u8 val)
{
int ret;
ret = i2c_smbus_write_byte_data(data->client, reg, val);
if (ret < 0)
dev_err(&data->client->dev, "Error %d writing reg 0x%02x\n", ret, reg);
return ret;
}
static int lc824206xa_get_id(struct lc824206xa_data *data)
{
int ret;
ret = lc824206xa_write_reg(data, REG_ID_PIN_ADC_CTRL, ID_PIN_ADC_CONTINUOUS);
if (ret)
return ret;
ret = lc824206xa_read_reg(data, REG_ID_PIN_ADC_VALUE);
lc824206xa_write_reg(data, REG_ID_PIN_ADC_CTRL, ID_PIN_ADC_AUTO);
return ret;
}
static void lc824206xa_set_vbus_boost(struct lc824206xa_data *data, bool enable)
{
int ret;
if (data->vbus_boost_enabled == enable)
return;
if (enable)
ret = regulator_enable(data->vbus_boost);
else
ret = regulator_disable(data->vbus_boost);
if (ret == 0)
data->vbus_boost_enabled = enable;
else
dev_err(&data->client->dev, "Error updating Vbus boost regulator: %d\n", ret);
}
static void lc824206xa_charger_detect(struct lc824206xa_data *data)
{
int charger_type, ret;
charger_type = lc824206xa_read_reg(data, REG_CHARGER_TYPE);
if (charger_type < 0)
return;
dev_dbg(&data->client->dev, "charger type 0x%02x\n", charger_type);
switch (charger_type) {
case CHARGER_TYPE_UNKNOWN:
data->usb_type = POWER_SUPPLY_USB_TYPE_UNKNOWN;
/* Treat as SDP */
data->cable = EXTCON_CHG_USB_SDP;
data->switch_control = SWITCH_USB_DEVICE;
break;
case CHARGER_TYPE_SDP_OR_CDP:
data->usb_type = POWER_SUPPLY_USB_TYPE_SDP;
data->cable = EXTCON_CHG_USB_SDP;
data->switch_control = SWITCH_USB_DEVICE;
ret = lc824206xa_write_reg(data, REG_CHARGER_DET,
CHARGER_DET_CDP_ON | CHARGER_DET_ON);
if (ret < 0)
break;
msleep(100);
ret = lc824206xa_read_reg(data, REG_CHARGER_DET);
if (ret >= 0 && (ret & CHARGER_DET_CDP_VAL)) {
data->usb_type = POWER_SUPPLY_USB_TYPE_CDP;
data->cable = EXTCON_CHG_USB_CDP;
}
lc824206xa_write_reg(data, REG_CHARGER_DET, CHARGER_DET_ON);
break;
case CHARGER_TYPE_DCP:
data->usb_type = POWER_SUPPLY_USB_TYPE_DCP;
data->cable = EXTCON_CHG_USB_DCP;
if (data->fastcharge_over_miclr)
data->switch_control = SWITCH_STEREO_MIC;
else
data->switch_control = SWITCH_DISCONNECTED;
break;
case CHARGER_TYPE_QC:
data->usb_type = POWER_SUPPLY_USB_TYPE_DCP;
data->cable = EXTCON_CHG_USB_DCP;
data->switch_control = SWITCH_DISCONNECTED;
break;
default:
dev_warn(&data->client->dev, "Unknown charger type: 0x%02x\n", charger_type);
break;
}
}
static void lc824206xa_work(struct work_struct *work)
{
struct lc824206xa_data *data = container_of(work, struct lc824206xa_data, work);
bool vbus_boost_enable = false;
int status, id;
status = lc824206xa_read_reg(data, REG_STATUS);
if (status < 0)
return;
dev_dbg(&data->client->dev, "status 0x%02x\n", status);
data->vbus_ok = (status & (STATUS_VBUS_PRESENT | STATUS_OVP)) == STATUS_VBUS_PRESENT;
/* Read id pin ADC if necessary */
switch (status & STATUS_USB_ID) {
case STATUS_USB_ID_GND:
case STATUS_USB_ID_FLOAT:
break;
default:
/* Happens when the connector is inserted slowly, log at dbg level */
dev_dbg(&data->client->dev, "Unknown status 0x%02x\n", status);
fallthrough;
case STATUS_USB_ID_ACA:
id = lc824206xa_get_id(data);
dev_dbg(&data->client->dev, "RID 0x%02x\n", id);
switch (id) {
case 0x10:
status = STATUS_USB_ID_GND;
break;
case 0x18 ... 0x1e:
status = STATUS_USB_ID_ACA;
break;
case 0x1f:
status = STATUS_USB_ID_FLOAT;
break;
default:
dev_warn(&data->client->dev, "Unknown RID 0x%02x\n", id);
return;
}
}
/* Check for out of spec OTG charging hubs, treat as ACA */
if ((status & STATUS_USB_ID) == STATUS_USB_ID_GND &&
data->vbus_ok && !data->vbus_boost_enabled) {
dev_info(&data->client->dev, "Out of spec USB host adapter with Vbus present, not enabling 5V output\n");
status = STATUS_USB_ID_ACA;
}
switch (status & STATUS_USB_ID) {
case STATUS_USB_ID_ACA:
data->usb_type = POWER_SUPPLY_USB_TYPE_ACA;
data->cable = EXTCON_CHG_USB_ACA;
data->switch_control = SWITCH_USB_HOST;
break;
case STATUS_USB_ID_GND:
data->usb_type = POWER_SUPPLY_USB_TYPE_UNKNOWN;
data->cable = EXTCON_USB_HOST;
data->switch_control = SWITCH_USB_HOST;
vbus_boost_enable = true;
break;
case STATUS_USB_ID_FLOAT:
/* When fast charging with Vbus > 5V, OVP will be set */
if (data->fastcharge_over_miclr &&
data->switch_control == SWITCH_STEREO_MIC &&
(status & STATUS_OVP)) {
data->cable = EXTCON_CHG_USB_FAST;
break;
}
if (data->vbus_ok) {
lc824206xa_charger_detect(data);
} else {
data->usb_type = POWER_SUPPLY_USB_TYPE_UNKNOWN;
data->cable = EXTCON_NONE;
data->switch_control = SWITCH_DISCONNECTED;
}
break;
}
lc824206xa_set_vbus_boost(data, vbus_boost_enable);
if (data->switch_control != data->previous_switch_control) {
lc824206xa_write_reg(data, REG_SWITCH_CONTROL, data->switch_control);
data->previous_switch_control = data->switch_control;
}
if (data->cable != data->previous_cable) {
extcon_set_state_sync(data->edev, data->previous_cable, false);
extcon_set_state_sync(data->edev, data->cable, true);
data->previous_cable = data->cable;
}
power_supply_changed(data->psy);
}
static irqreturn_t lc824206xa_irq(int irq, void *_data)
{
struct lc824206xa_data *data = _data;
int intr_status;
intr_status = lc824206xa_read_reg(data, REG_INTR_STATUS);
if (intr_status < 0)
intr_status = INTR_ALL; /* Should never happen, clear all */
dev_dbg(&data->client->dev, "interrupt 0x%02x\n", intr_status);
lc824206xa_write_reg(data, REG_INTR_CLEAR, intr_status);
lc824206xa_write_reg(data, REG_INTR_CLEAR, 0);
schedule_work(&data->work);
return IRQ_HANDLED;
}
/*
* Newer charger (power_supply) drivers expect the max input current to be
* provided by a parent power_supply device for the charger chip.
*/
static int lc824206xa_psy_get_prop(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val)
{
struct lc824206xa_data *data = power_supply_get_drvdata(psy);
switch (psp) {
case POWER_SUPPLY_PROP_ONLINE:
val->intval = data->vbus_ok && !data->vbus_boost_enabled;
break;
case POWER_SUPPLY_PROP_USB_TYPE:
val->intval = data->usb_type;
break;
case POWER_SUPPLY_PROP_CURRENT_MAX:
switch (data->usb_type) {
case POWER_SUPPLY_USB_TYPE_DCP:
case POWER_SUPPLY_USB_TYPE_ACA:
val->intval = 2000000;
break;
case POWER_SUPPLY_USB_TYPE_CDP:
val->intval = 1500000;
break;
default:
val->intval = 500000;
}
break;
default:
return -EINVAL;
}
return 0;
}
static const enum power_supply_usb_type lc824206xa_psy_usb_types[] = {
POWER_SUPPLY_USB_TYPE_SDP,
POWER_SUPPLY_USB_TYPE_CDP,
POWER_SUPPLY_USB_TYPE_DCP,
POWER_SUPPLY_USB_TYPE_ACA,
POWER_SUPPLY_USB_TYPE_UNKNOWN,
};
static const enum power_supply_property lc824206xa_psy_props[] = {
POWER_SUPPLY_PROP_ONLINE,
POWER_SUPPLY_PROP_USB_TYPE,
POWER_SUPPLY_PROP_CURRENT_MAX,
};
static const struct power_supply_desc lc824206xa_psy_desc = {
.name = "lc824206xa-charger-detect",
.type = POWER_SUPPLY_TYPE_USB,
.usb_types = lc824206xa_psy_usb_types,
.num_usb_types = ARRAY_SIZE(lc824206xa_psy_usb_types),
.properties = lc824206xa_psy_props,
.num_properties = ARRAY_SIZE(lc824206xa_psy_props),
.get_property = lc824206xa_psy_get_prop,
};
static int lc824206xa_probe(struct i2c_client *client)
{
struct power_supply_config psy_cfg = { };
struct device *dev = &client->dev;
struct lc824206xa_data *data;
int ret;
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->client = client;
INIT_WORK(&data->work, lc824206xa_work);
data->cable = EXTCON_NONE;
data->previous_cable = EXTCON_NONE;
data->usb_type = POWER_SUPPLY_USB_TYPE_UNKNOWN;
/* Some designs use a custom fast-charge protocol over the mic L/R inputs */
data->fastcharge_over_miclr =
device_property_read_bool(dev, "onnn,enable-miclr-for-dcp");
data->vbus_boost = devm_regulator_get(dev, "vbus");
if (IS_ERR(data->vbus_boost))
return dev_err_probe(dev, PTR_ERR(data->vbus_boost),
"getting regulator\n");
/* Init */
ret = lc824206xa_write_reg(data, REG00, REG00_INIT_VALUE);
ret |= lc824206xa_write_reg(data, REG10, REG10_INIT_VALUE);
msleep(100);
ret |= lc824206xa_write_reg(data, REG_INTR_CLEAR, INTR_ALL);
ret |= lc824206xa_write_reg(data, REG_INTR_CLEAR, 0);
ret |= lc824206xa_write_reg(data, REG_INTR_MASK, INTR_MASK);
ret |= lc824206xa_write_reg(data, REG_ID_PIN_ADC_CTRL, ID_PIN_ADC_AUTO);
ret |= lc824206xa_write_reg(data, REG_CHARGER_DET, CHARGER_DET_ON);
if (ret)
return -EIO;
/* Initialize extcon device */
data->edev = devm_extcon_dev_allocate(dev, lc824206xa_cables);
if (IS_ERR(data->edev))
return PTR_ERR(data->edev);
ret = devm_extcon_dev_register(dev, data->edev);
if (ret)
return dev_err_probe(dev, ret, "registering extcon device\n");
psy_cfg.drv_data = data;
data->psy = devm_power_supply_register(dev, &lc824206xa_psy_desc, &psy_cfg);
if (IS_ERR(data->psy))
return dev_err_probe(dev, PTR_ERR(data->psy), "registering power supply\n");
ret = devm_request_threaded_irq(dev, client->irq, NULL, lc824206xa_irq,
IRQF_TRIGGER_LOW | IRQF_ONESHOT,
KBUILD_MODNAME, data);
if (ret)
return dev_err_probe(dev, ret, "requesting IRQ\n");
/* Sync initial state */
schedule_work(&data->work);
return 0;
}
static const struct i2c_device_id lc824206xa_i2c_ids[] = {
{ "lc824206xa" },
{ }
};
MODULE_DEVICE_TABLE(i2c, lc824206xa_i2c_ids);
static struct i2c_driver lc824206xa_driver = {
.driver = {
.name = KBUILD_MODNAME,
},
.probe = lc824206xa_probe,
.id_table = lc824206xa_i2c_ids,
};
module_i2c_driver(lc824206xa_driver);
MODULE_AUTHOR("Hans de Goede <hansg@kernel.org>");
MODULE_DESCRIPTION("LC824206XA Micro USB Switch driver");
MODULE_LICENSE("GPL");