power_supply: Add isp1704 charger detection driver
authorHeikki Krogerus <ext-heikki.krogerus@nokia.com>
Thu, 19 Aug 2010 12:09:36 +0000 (15:09 +0300)
committerAnton Vorontsov <cbouatmailru@gmail.com>
Thu, 19 Aug 2010 12:25:20 +0000 (16:25 +0400)
NXP ISP1704 is Battery Charging Specification 1.0 compliant USB
transceiver. This adds a power supply driver for ISP1704 and
ISP1707 USB transceivers.

Signed-off-by: Heikki Krogerus <ext-heikki.krogerus@nokia.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
drivers/power/Kconfig
drivers/power/Makefile
drivers/power/isp1704_charger.c [new file with mode: 0644]

index 0734356..c2a1b8b 100644 (file)
@@ -166,4 +166,11 @@ config BATTERY_INTEL_MID
          Say Y here to enable the battery driver on Intel MID
          platforms.
 
+config CHARGER_ISP1704
+       tristate "ISP1704 USB Charger Detection"
+       depends on USB_OTG_UTILS
+       help
+         Say Y to enable support for USB Charger Detection with
+         ISP1707/ISP1704 USB transceivers.
+
 endif # POWER_SUPPLY
index 10143aa..c73d381 100644 (file)
@@ -37,3 +37,4 @@ obj-$(CONFIG_BATTERY_S3C_ADC) += s3c_adc_battery.o
 obj-$(CONFIG_CHARGER_PCF50633) += pcf50633-charger.o
 obj-$(CONFIG_BATTERY_JZ4740)   += jz4740-battery.o
 obj-$(CONFIG_BATTERY_INTEL_MID)        += intel_mid_battery.o
+obj-$(CONFIG_CHARGER_ISP1704)  += isp1704_charger.o
diff --git a/drivers/power/isp1704_charger.c b/drivers/power/isp1704_charger.c
new file mode 100644 (file)
index 0000000..7251218
--- /dev/null
@@ -0,0 +1,369 @@
+/*
+ * 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");