Introduce usb charger framework to deal with the usb gadget power negotation

-----Original Message-----
From: [email protected] [mailto:linux-usb-
[email protected]] On Behalf Of Baolin Wang
Sent: Monday, June 13, 2016 4:47 PM
To: [email protected]; [email protected]; [email protected]; [email protected]; [email protected]
Cc: [email protected]; [email protected]; [email protected]; [email protected]; stern-nwvwT67g6+6dFdvTe/[email protected]; [email protected]; [email protected]; [email protected]; [email protected]; ckeepax-yzvPICuk2AATkU/[email protected]; patches-yzvPICuk2AATkU/[email protected]; [email protected]; [email protected]; linux- [email protected]; device-mainlining-cunTk1MwBs98uUxBSJOaYoYkZiVZrdSR2LY78lusg7I@public.gmane.org; linux- [email protected]
Subject: [RESEND PATCH v11 1/4] gadget: Introduce the usb charger
framework

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 <[email protected]>

---
 drivers/usb/gadget/Kconfig       |    7 +
 drivers/usb/gadget/udc/Makefile  |    1 +
 drivers/usb/gadget/udc/charger.c |  770
++++++++++++++++++++++++++++++++++++++
 include/linux/usb/charger.h      |  191 ++++++++++
 include/uapi/linux/usb/charger.h |   31 ++
 5 files changed, 1000 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

Hi

Quoted 34 lines

-----Original Message-----
From: [email protected] [mailto:linux-usb- [email protected]] On Behalf Of Baolin Wang
Sent: Monday, June 13, 2016 4:47 PM
To: [email protected]; [email protected]; [email protected]; [email protected]; [email protected]
Cc: [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; linux- [email protected]; [email protected]; linux- [email protected]
Subject: [RESEND PATCH v11 1/4] gadget: Introduce the usb charger framework

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.

Quoted 5 lines

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 <[email protected]>

Reviewed-by Li Jun <[email protected]>

Tested-by Li Jun <[email protected]>

Quoted 12 lines

---
 drivers/usb/gadget/Kconfig       |    7 +
 drivers/usb/gadget/udc/Makefile  |    1 +
 drivers/usb/gadget/udc/charger.c |  770
++++++++++++++++++++++++++++++++++++++
 include/linux/usb/charger.h      |  191 ++++++++++
 include/uapi/linux/usb/charger.h |   31 ++
 5 files changed, 1000 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

Quoted 38 lines

Quoted 38 lines

-----Original Message-----
From: [email protected] [mailto:linux-usb- [email protected]] On Behalf Of Baolin Wang
Sent: Monday, June 13, 2016 4:47 PM
To: [email protected]; [email protected]; [email protected]; [email protected]; [email protected]
Cc: [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; linux- [email protected]; [email protected]; linux- [email protected]
Subject: [RESEND PATCH v11 1/4] gadget: Introduce the usb charger framework

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.

Quoted 4 lines

Quoted 1 line

Signed-off-by Baolin Wang <[email protected]>

Reviewed-by Li Jun <[email protected]>

Tested-by Li Jun <[email protected]>

Do you have any comments about this patchset, if not I will resend it with testing by Li Jun (thanks for Jun reviewing and testing). Thanks.

Hi Baolin,

Quoted 40 lines · Baolin Wang

Quoted 40 lines

Quoted 39 lines

-----Original Message-----
From: [email protected] [mailto:linux-usb- [email protected]] On Behalf Of Baolin Wang
Sent: Monday, June 13, 2016 4:47 PM
To: [email protected]; [email protected]; [email protected]; [email protected]; [email protected]
Cc: [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; linux- [email protected]; [email protected]; linux- [email protected]
Subject: [RESEND PATCH v11 1/4] gadget: Introduce the usb charger framework

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 <[email protected]>

Quoted 5 lines

Quoted 2 lines

Reviewed-by Li Jun <[email protected]>

Tested-by Li Jun <[email protected]>

Do you have any comments about this patchset, if not I will resend it with testing by Li Jun (thanks for Jun reviewing and testing). Thanks.

please resend. I don't have the series in my queue anymore, sorry.

-----Original Message-----
From: [email protected] [mailto:linux-usb- [email protected]] On Behalf Of Baolin Wang
Sent: Monday, June 13, 2016 4:47 PM
To: [email protected]; [email protected]; [email protected]; [email protected]; [email protected]
Cc: [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; linux- [email protected]; [email protected]; linux- [email protected]
Subject: [RESEND PATCH v11 2/4] gadget: Support for the usb charger framework

For supporting the usb charger, it adds the usb_charger_init() and usb_charger_exit() functions for usb charger initialization and exit.

It will report to the usb charger when the gadget state is changed, then the usb charger can do the power things.

Signed-off-by Baolin Wang <[email protected]>

---
 drivers/usb/gadget/udc/udc-core.c |   11 +++++++++++
 include/linux/usb/gadget.h        |   11 +++++++++++
 2 files changed, 22 insertions(+)

-----Original Message-----
From: [email protected] [mailto:linux-usb-
[email protected]] On Behalf Of Baolin Wang
Sent: Monday, June 13, 2016 4:47 PM
To: [email protected]; [email protected]; [email protected]; [email protected]; [email protected]
Cc: [email protected]; [email protected]; [email protected]; [email protected]; stern-nwvwT67g6+6dFdvTe/[email protected]; [email protected]; [email protected]; [email protected]; [email protected]; ckeepax-yzvPICuk2AATkU/[email protected]; patches-yzvPICuk2AATkU/[email protected]; [email protected]; [email protected]; linux- [email protected]; device-mainlining-cunTk1MwBs98uUxBSJOaYoYkZiVZrdSR2LY78lusg7I@public.gmane.org; linux- [email protected]
Subject: [RESEND PATCH v11 3/4] gadget: Integrate with the usb gadget
supporting for usb charger

When the usb gadget supporting for usb charger is ready, the usb charger can implement the usb_charger_plug_by_gadget() function and usb_charger_exit() function by getting 'struct usb_charger' from 'struct gadget'.

Signed-off-by Baolin Wang <[email protected]>

---
 drivers/usb/gadget/udc/charger.c |   39
+++++++++++++++++++++++++++++++++++++-
 1 file changed, 38 insertions(+), 1 deletion(-)

Integrate with the newly added USB charger interface to limit the current we draw from the USB input based on the input device configuration identified by the USB stack, allowing us to charge more quickly from high current inputs without drawing more current than specified from others.

Signed-off-by Mark Brown <[email protected]>

Signed-off-by Baolin Wang <[email protected]>

Acked-by Lee Jones <[email protected]>

Acked-by Charles Keepax <[email protected]>

Acked-by Peter Chen <[email protected]>

Acked-by Sebastian Reichel <[email protected]>

---
 drivers/power/wm831x_power.c     |   69 ++++++++++++++++++++++++++++++++++++++
 include/linux/mfd/wm831x/pdata.h |    3 ++

 2 files changed, 72 insertions(+)

drivers/power/wm831x_power.c +69 -0

index 7082301..cef1812 100644
@@ -13,6 +13,7 @@
 #include <linux/platform_device.h>
 #include <linux/power_supply.h>
 #include <linux/slab.h>
+#include <linux/usb/charger.h>
 
 #include <linux/mfd/wm831x/core.h>
 #include <linux/mfd/wm831x/auxadc.h>

@@ -31,6 +32,8 @@ struct wm831x_power {
 	char usb_name[20];
 	char battery_name[20];
 	bool have_battery;
+	struct usb_charger *usb_charger;
+	struct notifier_block usb_notify;
 };
 
 static int wm831x_power_check_online(struct wm831x *wm831x, int supply,

@@ -125,6 +128,43 @@ static enum power_supply_property wm831x_usb_props[] = {
 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
 };
 
+/* In milliamps */
+static const unsigned int wm831x_usb_limits[] = {
+	0,
+	2,
+	100,
+	500,
+	900,
+	1500,
+	1800,
+	550,
+};
+
+static int wm831x_usb_limit_change(struct notifier_block *nb,
+				   unsigned long limit, void *data)
+{
+	struct wm831x_power *wm831x_power = container_of(nb,
+							 struct wm831x_power,
+							 usb_notify);
+	unsigned int i, best;
+
+	/* Find the highest supported limit */
+	best = 0;
+	for (i = 0; i < ARRAY_SIZE(wm831x_usb_limits); i++) {
+		if (limit >= wm831x_usb_limits[i] &&
+		    wm831x_usb_limits[best] < wm831x_usb_limits[i])
+			best = i;
+	}
+
+	dev_dbg(wm831x_power->wm831x->dev,
+		"Limiting USB current to %umA", wm831x_usb_limits[best]);
+
+	wm831x_set_bits(wm831x_power->wm831x, WM831X_POWER_STATE,
+		        WM831X_USB_ILIM_MASK, best);
+
+	return 0;
+}
+
 /*********************************************************************
  *		Battery properties
  *********************************************************************/

@@ -607,8 +647,31 @@ static int wm831x_power_probe(struct platform_device *pdev)
 		}
 	}
 
+	if (wm831x_pdata && wm831x_pdata->usb_gadget) {
+		power->usb_charger =
+			usb_charger_find_by_name(wm831x_pdata->usb_gadget);
+		if (IS_ERR(power->usb_charger)) {
+			ret = PTR_ERR(power->usb_charger);
+			dev_err(&pdev->dev,
+				"Failed to find USB gadget: %d\n", ret);
+			goto err_bat_irq;
+		}
+
+		power->usb_notify.notifier_call = wm831x_usb_limit_change;
+
+		ret = usb_charger_register_notify(power->usb_charger,
+						  &power->usb_notify);
+		if (ret != 0) {
+			dev_err(&pdev->dev,
+				"Failed to register notifier: %d\n", ret);
+			goto err_usb_charger;
+		}
+	}
+
 	return ret;
 
+err_usb_charger:
+	/* put_device on charger */
 err_bat_irq:
 	--i;
 	for (; i >= 0; i--) {

@@ -637,6 +700,12 @@ static int wm831x_power_remove(struct platform_device *pdev)
 	struct wm831x *wm831x = wm831x_power->wm831x;
 	int irq, i;
 
+	if (wm831x_power->usb_charger) {
+		usb_charger_unregister_notify(wm831x_power->usb_charger,
+					      &wm831x_power->usb_notify);
+		/* Free charger */
+	}
+
 	for (i = 0; i < ARRAY_SIZE(wm831x_bat_irqs); i++) {
 		irq = wm831x_irq(wm831x, 
 				 platform_get_irq_byname(pdev,

include/linux/mfd/wm831x/pdata.h +3 -0

index dcc9631..5af8399 100644
@@ -126,6 +126,9 @@ struct wm831x_pdata {
 	/** The driver should initiate a power off sequence during shutdown */
 	bool soft_shutdown;
 
+	/** dev_name of USB charger gadget to integrate with */
+	const char *usb_gadget;
+
 	int irq_base;
 	int gpio_base;
 	int gpio_defaults[WM831X_GPIO_NUM];