[PATCH v18 1/4] usb: gadget: Introduce the usb charger framework

2016-10-18 Thread Baolin Wang 
This patch introduces the usb charger driver based on usb gadget that
makes an enhancement to a power driver. It works well in practice but
that requires a system with suitable hardware.

The basic conception of the usb charger is that, when one usb charger
is added or removed by reporting from the usb gadget state change or
the extcon device state change, the usb charger will report to power
user to set the current limitation.

The usb charger will register notifiees on the usb gadget or the extcon
device to get notified the usb charger state. It also supplies the
notification mechanism to userspace When the usb charger state is changed.

Power user will register a notifiee on the usb charger to get notified
by status changes from the usb charger. It will report to power user
to set the current limitation when detecting the usb charger is added
or removed from extcon device state or usb gadget state.

This patch doesn't yet integrate with the gadget code, so some functions
which rely on the 'gadget' are not completed, that will be implemented
in the following patches.

Signed-off-by: Baolin Wang 
Reviewed-by: Li Jun 
Tested-by: Li Jun 
---
 drivers/usb/gadget/Kconfig   |8 +
 drivers/usb/gadget/udc/Makefile  |1 +
 drivers/usb/gadget/udc/charger.c |  782 ++
 include/linux/usb/charger.h  |  185 +
 include/uapi/linux/usb/charger.h |   31 ++
 5 files changed, 1007 insertions(+)
 create mode 100644 drivers/usb/gadget/udc/charger.c
 create mode 100644 include/linux/usb/charger.h
 create mode 100644 include/uapi/linux/usb/charger.h

diff --git a/drivers/usb/gadget/Kconfig b/drivers/usb/gadget/Kconfig
index 2ea3fc3..7520677 100644
--- a/drivers/usb/gadget/Kconfig
+++ b/drivers/usb/gadget/Kconfig
@@ -134,6 +134,14 @@ config U_SERIAL_CONSOLE
help
   It supports the serial gadget can be used as a console.
 
+config USB_CHARGER
+   bool "USB charger support"
+   select EXTCON
+   help
+ The usb charger driver based on the usb gadget that makes an
+ enhancement to a power driver which can set the current limitation
+ when the usb charger is added or removed.
+
 source "drivers/usb/gadget/udc/Kconfig"
 
 #
diff --git a/drivers/usb/gadget/udc/Makefile b/drivers/usb/gadget/udc/Makefile
index 98e74ed..ede2351 100644
--- a/drivers/usb/gadget/udc/Makefile
+++ b/drivers/usb/gadget/udc/Makefile
@@ -2,6 +2,7 @@
 CFLAGS_trace.o := -I$(src)
 
 udc-core-y := core.o trace.o
+udc-core-$(CONFIG_USB_CHARGER) += charger.o
 
 #
 # USB peripheral controller drivers
diff --git a/drivers/usb/gadget/udc/charger.c b/drivers/usb/gadget/udc/charger.c
new file mode 100644
index 000..d885e86
--- /dev/null
+++ b/drivers/usb/gadget/udc/charger.c
@@ -0,0 +1,782 @@
+/*
+ * charger.c -- USB charger driver
+ *
+ * Copyright (C) 2016 Linaro Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+
+/* Default current range by charger type. */
+#define DEFAULT_SDP_CUR_MIN2
+#define DEFAULT_SDP_CUR_MAX500
+#define DEFAULT_SDP_CUR_MIN_SS 150
+#define DEFAULT_SDP_CUR_MAX_SS 900
+#define DEFAULT_DCP_CUR_MIN500
+#define DEFAULT_DCP_CUR_MAX5000
+#define DEFAULT_CDP_CUR_MIN1500
+#define DEFAULT_CDP_CUR_MAX5000
+#define DEFAULT_ACA_CUR_MIN1500
+#define DEFAULT_ACA_CUR_MAX5000
+
+static DEFINE_IDA(usb_charger_ida);
+static LIST_HEAD(charger_list);
+static DEFINE_MUTEX(charger_lock);
+
+static struct usb_charger *dev_to_uchger(struct device *dev)
+{
+   return NULL;
+}
+
+/*
+ * charger_current_show() - Show the charger current.
+ */
+static ssize_t charger_current_show(struct device *dev,
+   struct device_attribute *attr,
+   char *buf)
+{
+   struct usb_charger *uchger = dev_to_uchger(dev);
+   unsigned int min, max;
+
+   usb_charger_get_current(uchger, , );
+   return sprintf(buf, "%u-%u\n", min, max);
+}
+static DEVICE_ATTR_RO(charger_current);
+
+/*
+ * charger_type_show() - Show the charger type.
+ *
+ * It can be SDP/DCP/CDP/ACA type, else for unknown type.
+ */
+static ssize_t charger_type_show(struct device *dev,
+struct device_attribute *attr,
+char *buf)
+{
+   struct usb_charger *uchger = dev_to_uchger(dev);
+   int cnt;
+
+   switch (uchger->type) {
+   case SDP_TYPE:
+   cnt = sprintf(buf, "%s\n", "SDP");
+   break;
+   case DCP_TYPE:
+   cnt = sprintf(buf, "%s\n", "DCP");
+   break;
+   case CDP_TYPE:
+   cnt =

[PATCH v18 1/4] usb: gadget: Introduce the usb charger framework

2016-10-18 Thread Baolin Wang 
This patch introduces the usb charger driver based on usb gadget that
makes an enhancement to a power driver. It works well in practice but
that requires a system with suitable hardware.

The basic conception of the usb charger is that, when one usb charger
is added or removed by reporting from the usb gadget state change or
the extcon device state change, the usb charger will report to power
user to set the current limitation.

The usb charger will register notifiees on the usb gadget or the extcon
device to get notified the usb charger state. It also supplies the
notification mechanism to userspace When the usb charger state is changed.

Power user will register a notifiee on the usb charger to get notified
by status changes from the usb charger. It will report to power user
to set the current limitation when detecting the usb charger is added
or removed from extcon device state or usb gadget state.

This patch doesn't yet integrate with the gadget code, so some functions
which rely on the 'gadget' are not completed, that will be implemented
in the following patches.

Signed-off-by: Baolin Wang 
Reviewed-by: Li Jun 
Tested-by: Li Jun 
---
 drivers/usb/gadget/Kconfig   |8 +
 drivers/usb/gadget/udc/Makefile  |1 +
 drivers/usb/gadget/udc/charger.c |  782 ++
 include/linux/usb/charger.h  |  185 +
 include/uapi/linux/usb/charger.h |   31 ++
 5 files changed, 1007 insertions(+)
 create mode 100644 drivers/usb/gadget/udc/charger.c
 create mode 100644 include/linux/usb/charger.h
 create mode 100644 include/uapi/linux/usb/charger.h

diff --git a/drivers/usb/gadget/Kconfig b/drivers/usb/gadget/Kconfig
index 2ea3fc3..7520677 100644
--- a/drivers/usb/gadget/Kconfig
+++ b/drivers/usb/gadget/Kconfig
@@ -134,6 +134,14 @@ config U_SERIAL_CONSOLE
help
   It supports the serial gadget can be used as a console.
 
+config USB_CHARGER
+   bool "USB charger support"
+   select EXTCON
+   help
+ The usb charger driver based on the usb gadget that makes an
+ enhancement to a power driver which can set the current limitation
+ when the usb charger is added or removed.
+
 source "drivers/usb/gadget/udc/Kconfig"
 
 #
diff --git a/drivers/usb/gadget/udc/Makefile b/drivers/usb/gadget/udc/Makefile
index 98e74ed..ede2351 100644
--- a/drivers/usb/gadget/udc/Makefile
+++ b/drivers/usb/gadget/udc/Makefile
@@ -2,6 +2,7 @@
 CFLAGS_trace.o := -I$(src)
 
 udc-core-y := core.o trace.o
+udc-core-$(CONFIG_USB_CHARGER) += charger.o
 
 #
 # USB peripheral controller drivers
diff --git a/drivers/usb/gadget/udc/charger.c b/drivers/usb/gadget/udc/charger.c
new file mode 100644
index 000..d885e86
--- /dev/null
+++ b/drivers/usb/gadget/udc/charger.c
@@ -0,0 +1,782 @@
+/*
+ * charger.c -- USB charger driver
+ *
+ * Copyright (C) 2016 Linaro Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+
+/* Default current range by charger type. */
+#define DEFAULT_SDP_CUR_MIN2
+#define DEFAULT_SDP_CUR_MAX500
+#define DEFAULT_SDP_CUR_MIN_SS 150
+#define DEFAULT_SDP_CUR_MAX_SS 900
+#define DEFAULT_DCP_CUR_MIN500
+#define DEFAULT_DCP_CUR_MAX5000
+#define DEFAULT_CDP_CUR_MIN1500
+#define DEFAULT_CDP_CUR_MAX5000
+#define DEFAULT_ACA_CUR_MIN1500
+#define DEFAULT_ACA_CUR_MAX5000
+
+static DEFINE_IDA(usb_charger_ida);
+static LIST_HEAD(charger_list);
+static DEFINE_MUTEX(charger_lock);
+
+static struct usb_charger *dev_to_uchger(struct device *dev)
+{
+   return NULL;
+}
+
+/*
+ * charger_current_show() - Show the charger current.
+ */
+static ssize_t charger_current_show(struct device *dev,
+   struct device_attribute *attr,
+   char *buf)
+{
+   struct usb_charger *uchger = dev_to_uchger(dev);
+   unsigned int min, max;
+
+   usb_charger_get_current(uchger, , );
+   return sprintf(buf, "%u-%u\n", min, max);
+}
+static DEVICE_ATTR_RO(charger_current);
+
+/*
+ * charger_type_show() - Show the charger type.
+ *
+ * It can be SDP/DCP/CDP/ACA type, else for unknown type.
+ */
+static ssize_t charger_type_show(struct device *dev,
+struct device_attribute *attr,
+char *buf)
+{
+   struct usb_charger *uchger = dev_to_uchger(dev);
+   int cnt;
+
+   switch (uchger->type) {
+   case SDP_TYPE:
+   cnt = sprintf(buf, "%s\n", "SDP");
+   break;
+   case DCP_TYPE:
+   cnt = sprintf(buf, "%s\n", "DCP");
+   break;
+   case CDP_TYPE:
+   cnt = sprintf(buf, "%s\n", "CDP");
+   break;
+