// SPDX-License-Identifier: GPL-2.0
/*
* extcon driver for Basin Cove PMIC
*
* Copyright (c) 2019, Intel Corporation.
* Author: Andy Shevchenko <[email protected]>
*/
#include <linux/extcon-provider.h>
#include <linux/interrupt.h>
#include <linux/mfd/intel_soc_pmic.h>
#include <linux/mfd/intel_soc_pmic_mrfld.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include "extcon-intel.h"
#define BCOVE_USBIDCTRL 0x19
#define BCOVE_USBIDCTRL_ID BIT(0)
#define BCOVE_USBIDCTRL_ACA BIT(1)
#define BCOVE_USBIDCTRL_ALL (BCOVE_USBIDCTRL_ID | BCOVE_USBIDCTRL_ACA)
#define BCOVE_USBIDSTS 0x1a
#define BCOVE_USBIDSTS_GND BIT(0)
#define BCOVE_USBIDSTS_RARBRC_MASK GENMASK(2, 1)
#define BCOVE_USBIDSTS_RARBRC_SHIFT 1
#define BCOVE_USBIDSTS_NO_ACA 0
#define BCOVE_USBIDSTS_R_ID_A 1
#define BCOVE_USBIDSTS_R_ID_B 2
#define BCOVE_USBIDSTS_R_ID_C 3
#define BCOVE_USBIDSTS_FLOAT BIT(3)
#define BCOVE_USBIDSTS_SHORT BIT(4)
#define BCOVE_CHGRIRQ_ALL (BCOVE_CHGRIRQ_VBUSDET | BCOVE_CHGRIRQ_DCDET | \
BCOVE_CHGRIRQ_BATTDET | BCOVE_CHGRIRQ_USBIDDET)
#define BCOVE_CHGRCTRL0 0x4b
#define BCOVE_CHGRCTRL0_CHGRRESET BIT(0)
#define BCOVE_CHGRCTRL0_EMRGCHREN BIT(1)
#define BCOVE_CHGRCTRL0_EXTCHRDIS BIT(2)
#define BCOVE_CHGRCTRL0_SWCONTROL BIT(3)
#define BCOVE_CHGRCTRL0_TTLCK BIT(4)
#define BCOVE_CHGRCTRL0_BIT_5 BIT(5)
#define BCOVE_CHGRCTRL0_BIT_6 BIT(6)
#define BCOVE_CHGRCTRL0_CHR_WDT_NOKICK BIT(7)
struct mrfld_extcon_data {
struct device *dev;
struct regmap *regmap;
struct extcon_dev *edev;
unsigned int status;
unsigned int id;
};
static const unsigned int mrfld_extcon_cable[] = {
EXTCON_USB,
EXTCON_USB_HOST,
EXTCON_CHG_USB_SDP,
EXTCON_CHG_USB_CDP,
EXTCON_CHG_USB_DCP,
EXTCON_CHG_USB_ACA,
EXTCON_NONE,
};
static int mrfld_extcon_clear(struct mrfld_extcon_data *data, unsigned int reg,
unsigned int mask)
{
return regmap_update_bits(data->regmap, reg, mask, 0x00);
}
static int mrfld_extcon_set(struct mrfld_extcon_data *data, unsigned int reg,
unsigned int mask)
{
return regmap_update_bits(data->regmap, reg, mask, 0xff);
}
static int mrfld_extcon_sw_control(struct mrfld_extcon_data *data, bool enable)
{
unsigned int mask = BCOVE_CHGRCTRL0_SWCONTROL;
struct device *dev = data->dev;
int ret;
if (enable)
ret = mrfld_extcon_set(data, BCOVE_CHGRCTRL0, mask);
else
ret = mrfld_extcon_clear(data, BCOVE_CHGRCTRL0, mask);
if (ret)
dev_err(dev, "can't set SW control: %d\n", ret);
return ret;
}
static int mrfld_extcon_get_id(struct mrfld_extcon_data *data)
{
struct regmap *regmap = data->regmap;
unsigned int id;
bool ground;
int ret;
ret = regmap_read(regmap, BCOVE_USBIDSTS, &id);
if (ret)
return ret;
if (id & BCOVE_USBIDSTS_FLOAT)
return INTEL_USB_ID_FLOAT;
switch ((id & BCOVE_USBIDSTS_RARBRC_MASK) >> BCOVE_USBIDSTS_RARBRC_SHIFT) {
case BCOVE_USBIDSTS_R_ID_A:
return INTEL_USB_RID_A;
case BCOVE_USBIDSTS_R_ID_B:
return INTEL_USB_RID_B;
case BCOVE_USBIDSTS_R_ID_C:
return INTEL_USB_RID_C;
}
/*
* PMIC A0 reports USBIDSTS_GND = 1 for ID_GND,
* but PMIC B0 reports USBIDSTS_GND = 0 for ID_GND.
* Thus we must check this bit at last.
*/
ground = id & BCOVE_USBIDSTS_GND;
switch ('A' + BCOVE_MAJOR(data->id)) {
case 'A':
return ground ? INTEL_USB_ID_GND : INTEL_USB_ID_FLOAT;
case 'B':
return ground ? INTEL_USB_ID_FLOAT : INTEL_USB_ID_GND;
}
/* Unknown or unsupported type */
return INTEL_USB_ID_FLOAT;
}
static int mrfld_extcon_role_detect(struct mrfld_extcon_data *data)
{
unsigned int id;
bool usb_host;
int ret;
ret = mrfld_extcon_get_id(data);
if (ret < 0)
return ret;
id = ret;
usb_host = (id == INTEL_USB_ID_GND) || (id == INTEL_USB_RID_A);
extcon_set_state_sync(data->edev, EXTCON_USB_HOST, usb_host);
return 0;
}
static int mrfld_extcon_cable_detect(struct mrfld_extcon_data *data)
{
struct regmap *regmap = data->regmap;
unsigned int status, change;
int ret;
/*
* It seems SCU firmware clears the content of BCOVE_CHGRIRQ1
* and makes it useless for OS. Instead we compare a previously
* stored status to the current one, provided by BCOVE_SCHGRIRQ1.
*/
ret = regmap_read(regmap, BCOVE_SCHGRIRQ1, &status);
if (ret)
return ret;
change = status ^ data->status;
if (!change)
return -ENODATA;
if (change & BCOVE_CHGRIRQ_USBIDDET) {
ret = mrfld_extcon_role_detect(data);
if (ret)
return ret;
}
data->status = status;
return 0;
}
static irqreturn_t mrfld_extcon_interrupt(int irq, void *dev_id)
{
struct mrfld_extcon_data *data = dev_id;
int ret;
ret = mrfld_extcon_cable_detect(data);
mrfld_extcon_clear(data, BCOVE_MIRQLVL1, BCOVE_LVL1_CHGR);
return ret ? IRQ_NONE: IRQ_HANDLED;
}
static int mrfld_extcon_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct intel_soc_pmic *pmic = dev_get_drvdata(dev->parent);
struct regmap *regmap = pmic->regmap;
struct mrfld_extcon_data *data;
unsigned int status;
unsigned int id;
int irq, ret;
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->dev = dev;
data->regmap = regmap;
data->edev = devm_extcon_dev_allocate(dev, mrfld_extcon_cable);
if (IS_ERR(data->edev))
return PTR_ERR(data->edev);
ret = devm_extcon_dev_register(dev, data->edev);
if (ret < 0)
return dev_err_probe(dev, ret, "can't register extcon device\n");
ret = devm_request_threaded_irq(dev, irq, NULL, mrfld_extcon_interrupt,
IRQF_ONESHOT | IRQF_SHARED, pdev->name,
data);
if (ret)
return dev_err_probe(dev, ret, "can't register IRQ handler\n");
ret = regmap_read(regmap, BCOVE_ID, &id);
if (ret)
return dev_err_probe(dev, ret, "can't read PMIC ID\n");
data->id = id;
ret = mrfld_extcon_sw_control(data, true);
if (ret)
return ret;
/* Get initial state */
mrfld_extcon_role_detect(data);
/*
* Cached status value is used for cable detection, see comments
* in mrfld_extcon_cable_detect(), we need to sync cached value
* with a real state of the hardware.
*/
regmap_read(regmap, BCOVE_SCHGRIRQ1, &status);
data->status = status;
mrfld_extcon_clear(data, BCOVE_MIRQLVL1, BCOVE_LVL1_CHGR);
mrfld_extcon_clear(data, BCOVE_MCHGRIRQ1, BCOVE_CHGRIRQ_ALL);
mrfld_extcon_set(data, BCOVE_USBIDCTRL, BCOVE_USBIDCTRL_ALL);
platform_set_drvdata(pdev, data);
return 0;
}
static void mrfld_extcon_remove(struct platform_device *pdev)
{
struct mrfld_extcon_data *data = platform_get_drvdata(pdev);
mrfld_extcon_sw_control(data, false);
}
static const struct platform_device_id mrfld_extcon_id_table[] = {
{ .name = "mrfld_bcove_pwrsrc" },
{}
};
MODULE_DEVICE_TABLE(platform, mrfld_extcon_id_table);
static struct platform_driver mrfld_extcon_driver = {
.driver = {
.name = "mrfld_bcove_pwrsrc",
},
.probe = mrfld_extcon_probe,
.remove_new = mrfld_extcon_remove,
.id_table = mrfld_extcon_id_table,
};
module_platform_driver(mrfld_extcon_driver);
MODULE_AUTHOR("Andy Shevchenko <[email protected]>");
MODULE_DESCRIPTION("extcon driver for Intel Merrifield Basin Cove PMIC");
MODULE_LICENSE("GPL v2");