--- /dev/null
+/*
+ * 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[7];
+ 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");