USB: OTG: msm: Implement charger detection

Implement good battery algorithm defined in the battery charging V1.2 spec
for detecting different charging ports.  USB hardware is put into low power
mode when connected to a dedicated charging port.  vbus_draw and set_power
methods are implemented for determining the allowed current from Host in
different states (un-configured/suspend/configured).

The charger block is implemented using vendor specific registers and the
PHY used in MSM8960(28nm PHY) different from older targets like MSM8x60
and MSM7x30(45nm PHY).  The PHY vendor and product id registers are not
implemented in the above chipsets.  Hence PHY type is passed via platform
data.
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/ci13xxx_udc.c

@@ -2506,6 +2506,15 @@ static int ci13xxx_wakeup(struct usb_gadget *_gadget)
 	return ret;
 }
 
+static int ci13xxx_vbus_draw(struct usb_gadget *_gadget, unsigned mA)
+{
+	struct ci13xxx *udc = container_of(_gadget, struct ci13xxx, gadget);
+
+	if (udc->transceiver)
+		return otg_set_power(udc->transceiver, mA);
+	return -ENOTSUPP;
+}
+
 /**
  * Device operations part of the API to the USB controller hardware,
  * which don't involve endpoints (or i/o)
@@ -2514,6 +2523,7 @@ static int ci13xxx_wakeup(struct usb_gadget *_gadget)
 static const struct usb_gadget_ops usb_gadget_ops = {
 	.vbus_session	= ci13xxx_vbus_session,
 	.wakeup		= ci13xxx_wakeup,
+	.vbus_draw	= ci13xxx_vbus_draw,
 };
 
 /**

include/linux/usb/msm_hsusb.h

@@ -2,7 +2,7 @@
  *
  * Copyright (C) 2008 Google, Inc.
  * Author: Brian Swetland <swetland@google.com>
- * Copyright (c) 2009-2010, Code Aurora Forum. All rights reserved.
+ * Copyright (c) 2009-2011, Code Aurora Forum. All rights reserved.
  *
  * This software is licensed under the terms of the GNU General Public
  * License version 2, as published by the Free Software Foundation, and
@@ -53,6 +53,64 @@ enum otg_control_type {
 	OTG_USER_CONTROL,
 };
 
+/**
+ * PHY used in
+ *
+ * INVALID_PHY			Unsupported PHY
+ * CI_45NM_INTEGRATED_PHY	Chipidea 45nm integrated PHY
+ * SNPS_28NM_INTEGRATED_PHY	Synopsis 28nm integrated PHY
+ *
+ */
+enum msm_usb_phy_type {
+	INVALID_PHY = 0,
+	CI_45NM_INTEGRATED_PHY,
+	SNPS_28NM_INTEGRATED_PHY,
+};
+
+#define IDEV_CHG_MAX	1500
+#define IUNIT		100
+
+/**
+ * Different states involved in USB charger detection.
+ *
+ * USB_CHG_STATE_UNDEFINED	USB charger is not connected or detection
+ *                              process is not yet started.
+ * USB_CHG_STATE_WAIT_FOR_DCD	Waiting for Data pins contact.
+ * USB_CHG_STATE_DCD_DONE	Data pin contact is detected.
+ * USB_CHG_STATE_PRIMARY_DONE	Primary detection is completed (Detects
+ *                              between SDP and DCP/CDP).
+ * USB_CHG_STATE_SECONDARY_DONE	Secondary detection is completed (Detects
+ *                              between DCP and CDP).
+ * USB_CHG_STATE_DETECTED	USB charger type is determined.
+ *
+ */
+enum usb_chg_state {
+	USB_CHG_STATE_UNDEFINED = 0,
+	USB_CHG_STATE_WAIT_FOR_DCD,
+	USB_CHG_STATE_DCD_DONE,
+	USB_CHG_STATE_PRIMARY_DONE,
+	USB_CHG_STATE_SECONDARY_DONE,
+	USB_CHG_STATE_DETECTED,
+};
+
+/**
+ * USB charger types
+ *
+ * USB_INVALID_CHARGER	Invalid USB charger.
+ * USB_SDP_CHARGER	Standard downstream port. Refers to a downstream port
+ *                      on USB2.0 compliant host/hub.
+ * USB_DCP_CHARGER	Dedicated charger port (AC charger/ Wall charger).
+ * USB_CDP_CHARGER	Charging downstream port. Enumeration can happen and
+ *                      IDEV_CHG_MAX can be drawn irrespective of USB state.
+ *
+ */
+enum usb_chg_type {
+	USB_INVALID_CHARGER = 0,
+	USB_SDP_CHARGER,
+	USB_DCP_CHARGER,
+	USB_CDP_CHARGER,
+};
+
 /**
  * struct msm_otg_platform_data - platform device data
  *              for msm_otg driver.
@@ -74,6 +132,7 @@ struct msm_otg_platform_data {
 	enum usb_mode_type mode;
 	enum otg_control_type otg_control;
 	enum usb_mode_type default_mode;
+	enum msm_usb_phy_type phy_type;
 	void (*setup_gpio)(enum usb_otg_state state);
 	char *pclk_src_name;
 };
@@ -93,6 +152,12 @@ struct msm_otg_platform_data {
  * @sm_work: OTG state machine work.
  * @in_lpm: indicates low power mode (LPM) state.
  * @async_int: Async interrupt arrived.
+ * @cur_power: The amount of mA available from downstream port.
+ * @chg_work: Charger detection work.
+ * @chg_state: The state of charger detection process.
+ * @chg_type: The type of charger attached.
+ * @dcd_retires: The retry count used to track Data contact
+ *               detection process.
  */
 struct msm_otg {
 	struct otg_transceiver otg;
@@ -110,6 +175,11 @@ struct msm_otg {
 	struct work_struct sm_work;
 	atomic_t in_lpm;
 	int async_int;
+	unsigned cur_power;
+	struct delayed_work chg_work;
+	enum usb_chg_state chg_state;
+	enum usb_chg_type chg_type;
+	u8 dcd_retries;
 };
 
 #endif