/*
* ISP1704 USB Charger Detection driver
*
* Copyright (C) 2010 Nokia Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/device.h>
#include <linux/sysfs.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/delay.h>
#include <linux/usb/otg.h>
#include <linux/usb/ulpi.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
/* Vendor specific Power Control register */
#define ISP1704_PWR_CTRL 0x3d
#define ISP1704_PWR_CTRL_SWCTRL (1 << 0)
#define ISP1704_PWR_CTRL_DET_COMP (1 << 1)
#define ISP1704_PWR_CTRL_BVALID_RISE (1 << 2)
#define ISP1704_PWR_CTRL_BVALID_FALL (1 << 3)
#define ISP1704_PWR_CTRL_DP_WKPU_EN (1 << 4)
#define ISP1704_PWR_CTRL_VDAT_DET (1 << 5)
#define ISP1704_PWR_CTRL_DPVSRC_EN (1 << 6)
#define ISP1704_PWR_CTRL_HWDETECT (1 << 7)
#define NXP_VENDOR_ID 0x04cc
static u16 isp170x_id[] = {
0x1704,
0x1707,
};
struct isp1704_charger {
struct device *dev;
struct power_supply psy;
struct otg_transceiver *otg;
struct notifier_block nb;
struct work_struct work;
char model[8];
unsigned present:1;
};
/*
* ISP1704 detects PS/2 adapters as charger. To make sure the detected charger
* is actually a dedicated charger, the following steps need to be taken.
*/
static inline int isp1704_charger_verify(struct isp1704_charger *isp)
{
int ret = 0;
u8 r;
/* Reset the transceiver */
r = otg_io_read(isp->otg, ULPI_FUNC_CTRL);
r |= ULPI_FUNC_CTRL_RESET;
otg_io_write(isp->otg, ULPI_FUNC_CTRL, r);
usleep_range(1000, 2000);
/* Set normal mode */
r &= ~(ULPI_FUNC_CTRL_RESET | ULPI_FUNC_CTRL_OPMODE_MASK);
otg_io_write(isp->otg, ULPI_FUNC_CTRL, r);
/* Clear the DP and DM pull-down bits */
r = ULPI_OTG_CTRL_DP_PULLDOWN | ULPI_OTG_CTRL_DM_PULLDOWN;
otg_io_write(isp->otg, ULPI_CLR(ULPI_OTG_CTRL), r);
/* Enable strong pull-up on DP (1.5K) and reset */
r = ULPI_FUNC_CTRL_TERMSELECT | ULPI_FUNC_CTRL_RESET;
otg_io_write(isp->otg, ULPI_SET(ULPI_FUNC_CTRL), r);
usleep_range(1000, 2000);
/* Read the line state */
if (!otg_io_read(isp->otg, ULPI_DEBUG)) {
/* Disable strong pull-up on DP (1.5K) */
otg_io_write(isp->otg, ULPI_CLR(ULPI_FUNC_CTRL),
ULPI_FUNC_CTRL_TERMSELECT);
return 1;
}
/* Is it a charger or PS/2 connection */
/* Enable weak pull-up resistor on DP */
otg_io_write(isp->otg, ULPI_SET(ISP1704_PWR_CTRL),
ISP1704_PWR_CTRL_DP_WKPU_EN);
/* Disable strong pull-up on DP (1.5K) */
otg_io_write(isp->otg, ULPI_CLR(ULPI_FUNC_CTRL),
ULPI_FUNC_CTRL_TERMSELECT);
/* Enable weak pull-down resistor on DM */
otg_io_write(isp->otg, ULPI_SET(ULPI_OTG_CTRL),
ULPI_OTG_CTRL_DM_PULLDOWN);
/* It's a charger if the line states are clear */
if (!(otg_io_read(isp->otg, ULPI_DEBUG)))
ret = 1;
/* Disable weak pull-up resistor on DP */
otg_io_write(isp->otg, ULPI_CLR(ISP1704_PWR_CTRL),
ISP1704_PWR_CTRL_DP_WKPU_EN);
return ret;
}
static inline int isp1704_charger_detect(struct isp1704_charger *isp)
{
unsigned long timeout;
u8 r;
int ret = 0;
/* set SW control bit in PWR_CTRL register */
otg_io_write(isp->otg, ISP1704_PWR_CTRL,
ISP1704_PWR_CTRL_SWCTRL);
/* enable manual charger detection */
r = (ISP1704_PWR_CTRL_SWCTRL | ISP1704_PWR_CTRL_DPVSRC_EN);
otg_io_write(isp->otg, ULPI_SET(ISP1704_PWR_CTRL), r);
usleep_range(1000, 2000);
timeout = jiffies + msecs_to_jiffies(300);
do {
/* Check if there is a charger */
if (otg_io_read(isp->otg, ISP1704_PWR_CTRL)
& ISP1704_PWR_CTRL_VDAT_DET) {
ret = isp1704_charger_verify(isp);
break;
}
} while (!time_after(jiffies, timeout));
return ret;
}
static void isp1704_charger_work(struct work_struct *data)
{
int detect;
struct isp1704_charger *isp =
container_of(data, struct isp1704_charger, work);
/*
* FIXME Only supporting dedicated chargers even though isp1704 can
* detect HUB and HOST chargers. If the device has already been
* enumerated, the detection will break the connection.
*/
if (isp->otg->state != OTG_STATE_B_IDLE)
return;
/* disable data pullups */
if (isp->otg->gadget)
usb_gadget_disconnect(isp->otg->gadget);
/* detect charger */
detect = isp1704_charger_detect(isp);
if (detect) {
isp->present = detect;
power_supply_changed(&isp->psy);
}
/* enable data pullups */
if (isp->otg->gadget)
usb_gadget_connect(isp->otg->gadget);
}
static int isp1704_notifier_call(struct notifier_block *nb,
unsigned long event, void *unused)
{
struct isp1704_charger *isp =
container_of(nb, struct isp1704_charger, nb);
switch (event) {
case USB_EVENT_VBUS:
schedule_work(&isp->work);
break;
case USB_EVENT_NONE:
if (isp->present) {
isp->present = 0;
power_supply_changed(&isp->psy);
}
break;
default:
return NOTIFY_DONE;
}
return NOTIFY_OK;
}
static int isp1704_charger_get_property(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val)
{
struct isp1704_charger *isp =
container_of(psy, struct isp1704_charger, psy);
switch (psp) {
case POWER_SUPPLY_PROP_PRESENT:
val->intval = isp->present;
break;
case POWER_SUPPLY_PROP_MODEL_NAME:
val->strval = isp->model;
break;
case POWER_SUPPLY_PROP_MANUFACTURER:
val->strval = "NXP";
break;
default:
return -EINVAL;
}
return 0;
}
static enum power_supply_property power_props[] = {
POWER_SUPPLY_PROP_PRESENT,
POWER_SUPPLY_PROP_MODEL_NAME,
POWER_SUPPLY_PROP_MANUFACTURER,
};
static inline int isp1704_test_ulpi(struct isp1704_charger *isp)
{
int vendor;
int product;
int i;
int ret = -ENODEV;
/* Test ULPI interface */
ret = otg_io_write(isp->otg, ULPI_SCRATCH, 0xaa);
if (ret < 0)
return ret;
ret = otg_io_read(isp->otg, ULPI_SCRATCH);
if (ret < 0)
return ret;
if (ret != 0xaa)
return -ENODEV;
/* Verify the product and vendor id matches */
vendor = otg_io_read(isp->otg, ULPI_VENDOR_ID_LOW);
vendor |= otg_io_read(isp->otg, ULPI_VENDOR_ID_HIGH) << 8;
if (vendor != NXP_VENDOR_ID)
return -ENODEV;
product = otg_io_read(isp->otg, ULPI_PRODUCT_ID_LOW);
product |= otg_io_read(isp->otg, ULPI_PRODUCT_ID_HIGH) << 8;
for (i = 0; i < ARRAY_SIZE(isp170x_id); i++) {
if (product == isp170x_id[i]) {
sprintf(isp->model, "isp%x", product);
return product;
}
}
dev_err(isp->dev, "product id %x not matching known ids", product);
return -ENODEV;
}
static int __devinit isp1704_charger_probe(struct platform_device *pdev)
{
struct isp1704_charger *isp;
int ret = -ENODEV;
isp = kzalloc(sizeof *isp, GFP_KERNEL);
if (!isp)
return -ENOMEM;
isp->otg = otg_get_transceiver();
if (!isp->otg)
goto fail0;
ret = isp1704_test_ulpi(isp);
if (ret < 0)
goto fail1;
isp->dev = &pdev->dev;
platform_set_drvdata(pdev, isp);
isp->psy.name = "isp1704";
isp->psy.type = POWER_SUPPLY_TYPE_USB;
isp->psy.properties = power_props;
isp->psy.num_properties = ARRAY_SIZE(power_props);
isp->psy.get_property = isp1704_charger_get_property;
ret = power_supply_register(isp->dev, &isp->psy);
if (ret)
goto fail1;
/*
* REVISIT: using work in order to allow the otg notifications to be
* made atomically in the future.
*/
INIT_WORK(&isp->work, isp1704_charger_work);
isp->nb.notifier_call = isp1704_notifier_call;
ret = otg_register_notifier(isp->otg, &isp->nb);
if (ret)
goto fail2;
dev_info(isp->dev, "registered with product id %s\n", isp->model);
return 0;
fail2:
power_supply_unregister(&isp->psy);
fail1:
otg_put_transceiver(isp->otg);
fail0:
kfree(isp);
dev_err(&pdev->dev, "failed to register isp1704 with error %d\n", ret);
return ret;
}
static int __devexit isp1704_charger_remove(struct platform_device *pdev)
{
struct isp1704_charger *isp = platform_get_drvdata(pdev);
otg_unregister_notifier(isp->otg, &isp->nb);
power_supply_unregister(&isp->psy);
otg_put_transceiver(isp->otg);
kfree(isp);
return 0;
}
static struct platform_driver isp1704_charger_driver = {
.driver = {
.name = "isp1704_charger",
},
.probe = isp1704_charger_probe,
.remove = __devexit_p(isp1704_charger_remove),
};
static int __init isp1704_charger_init(void)
{
return platform_driver_register(&isp1704_charger_driver);
}
module_init(isp1704_charger_init);
static void __exit isp1704_charger_exit(void)
{
platform_driver_unregister(&isp1704_charger_driver);
}
module_exit(isp1704_charger_exit);
MODULE_ALIAS("platform:isp1704_charger");
MODULE_AUTHOR("Nokia Corporation");
MODULE_DESCRIPTION("ISP170x USB Charger driver");
MODULE_LICENSE("GPL");
