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

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

Introduce a callback 'get_charger_type' which will implemented by user for usb gadget operations to get the usb charger type.

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

Hello.

Quoted 7 lines · Baolin Wang

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

Introduce a callback 'get_charger_type' which will implemented by user for usb gadget operations to get the usb charger type.

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

[...]

include/linux/usb/gadget.h struct usb_gadget_ops { · line 540

Quoted 9 lines

include/linux/usb/gadget.h +1 -0

index 755e8bc..44d82f5 100644
@@ -537,6 +537,7 @@ struct usb_gadget_ops {
        struct usb_ep *(*match_ep)(struct usb_gadget *,
                        struct usb_endpoint_descriptor *,
                        struct usb_ss_ep_comp_descriptor *);
+       enum usb_charger_type   (*get_charger_type)(struct usb_gadget *);

^^^ please use space, not tab here

include/linux/usb/gadget.h struct usb_gadget { · line 615

Quoted 9 lines

include/linux/usb/gadget.h +1 -0

  };
 
  /**

@@ -611,6 +612,7 @@ struct usb_gadget {
        struct usb_otg_caps             *otg_caps;
        struct raw_notifier_head        nh;
        struct mutex                    lock;
+       struct usb_charger              *uchger;

Why not simply call the field 'charger'? :-)

[...]

WBR, Sergei

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]>

---
 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 db11ae6..72c661f 100644
@@ -13,6 +13,7 @@
 #include <linux/platform_device.h>
 #include <linux/power_supply.h>
 #include <linux/slab.h>
+#include <linux/usb/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 miliamps */
+static 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);
+	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 %dmA", wm831x_usb_limits[best]);
+
+	wm831x_set_bits(wm831x_power->wm831x, WM831X_POWER_STATE,
+		        WM831X_USB_ILIM_MASK, best);
+
+	return 0;
+}
+
 /*********************************************************************
  *		Battery properties
  *********************************************************************/

@@ -606,8 +646,31 @@ 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:
+	usb_charger_put(power->usb_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);
+		usb_charger_put(wm831x_power->usb_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];

Quoted 5 lines · Baolin Wang

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.

Quoted 5 lines

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

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

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

I'm not going to keep reviewing this. You should carry forward any Acks received onto subsequent submissions yourself.

Quoted 117 lines

 2 files changed, 72 insertions(+)

drivers/power/wm831x_power.c +69 -0

index db11ae6..72c661f 100644
@@ -13,6 +13,7 @@
 #include <linux/platform_device.h>
 #include <linux/power_supply.h>
 #include <linux/slab.h>
+#include <linux/usb/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 miliamps */
+static 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);
+     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 %dmA", wm831x_usb_limits[best]);
+
+     wm831x_set_bits(wm831x_power->wm831x, WM831X_POWER_STATE,
+                     WM831X_USB_ILIM_MASK, best);
+
+     return 0;
+}
+
 /*********************************************************************
  *           Battery properties
  *********************************************************************/

@@ -606,8 +646,31 @@ 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:
+     usb_charger_put(power->usb_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);
+             usb_charger_put(wm831x_power->usb_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 +0 -0

index dcc9631..5af8399 100644

include/linux/mfd/wm831x/pdata.h struct wm831x_pdata { · line 134

Quoted 9 lines

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

@@ -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];

--
Lee Jones
Linaro STMicroelectronics Landing Team Lead

Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

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]>

Quoted 5 lines · Baolin Wang

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.

Quoted 2 lines

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

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

When people (like Charles and Lee have) have reviewed a change you should add any tags they gave when you resend the change so they don't have to duplicate their work and other people know that the review has happened.