diff mbox

[v3,3/3] power: wm831x_power: Support USB charger current limit management

Message ID 4e3447ef209fbbdc3ee1c82428be2bc19c30bd30.1439866451.git.baolin.wang@linaro.org
State New
Headers show

Commit Message

(Exiting) Baolin Wang Aug. 18, 2015, 11:14 a.m. UTC
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 <broonie@kernel.org>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
---
 drivers/power/wm831x_power.c     |   69 ++++++++++++++++++++++++++++++++++++++
 include/linux/mfd/wm831x/pdata.h |    3 ++
 2 files changed, 72 insertions(+)

Comments

Lee Jones Aug. 18, 2015, 11:43 a.m. UTC | #1
On Tue, 18 Aug 2015, Baolin Wang wrote:

> 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 <broonie@kernel.org>
> Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
> ---
>  drivers/power/wm831x_power.c     |   69 ++++++++++++++++++++++++++++++++++++++
>  include/linux/mfd/wm831x/pdata.h |    3 ++

MFD:
  Acked-by: Lee Jones <lee.jones@linaro.org>

>  2 files changed, 72 insertions(+)
> 
> diff --git a/drivers/power/wm831x_power.c b/drivers/power/wm831x_power.c
> index db11ae6..72c661f 100644
> --- a/drivers/power/wm831x_power.c
> +++ b/drivers/power/wm831x_power.c
> @@ -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,
> diff --git a/include/linux/mfd/wm831x/pdata.h b/include/linux/mfd/wm831x/pdata.h
> index dcc9631..5af8399 100644
> --- a/include/linux/mfd/wm831x/pdata.h
> +++ b/include/linux/mfd/wm831x/pdata.h
> @@ -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 Aug. 18, 2015, 1:51 p.m. UTC | #2
On Tue, 18 Aug 2015, Charles Keepax wrote:

> On Tue, Aug 18, 2015 at 07:14:21PM +0800, Baolin Wang wrote:
> > 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 <broonie@kernel.org>
> > Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
> > ---
> 
> Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
> 
> Sorry if you guys got a bunch of bounces, we had a bit of an
> email fiasco at this end. Hopefully all fixed now.

Yes, I sent you guys a mail about that.

Glad it's all sorted now.
diff mbox

Patch

diff --git a/drivers/power/wm831x_power.c b/drivers/power/wm831x_power.c
index db11ae6..72c661f 100644
--- a/drivers/power/wm831x_power.c
+++ b/drivers/power/wm831x_power.c
@@ -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,
diff --git a/include/linux/mfd/wm831x/pdata.h b/include/linux/mfd/wm831x/pdata.h
index dcc9631..5af8399 100644
--- a/include/linux/mfd/wm831x/pdata.h
+++ b/include/linux/mfd/wm831x/pdata.h
@@ -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];