usb gadget: USB_GADGET_VBUS_DRAW Kconfig option

Offer a "how much VBUS power to request" configuration option
for USB gadgets that aren't using board-specific customization
of their gadget or (composite) configuration drivers.

Also remove a couple pointless "depends on USB_GADGET" bits
from the Kconfig text; booleans inside an "if USB_GADGET" will
already have that dependency.

Based on a patch from Justin Clacherty.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Justin Clacherty <justin@redfish-group.com>
Tested-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

10 files changed, 25 insertions, 15 deletions

diff --git a/drivers/usb/gadget/Kconfig b/drivers/usb/gadget/Kconfig
index c0dfd9be3115..1a72715bce8a 100644
--- a/drivers/usb/gadget/Kconfig
+++ b/drivers/usb/gadget/Kconfig
@@ -45,7 +45,7 @@ if USB_GADGET
 
 config USB_GADGET_DEBUG
         boolean "Debugging messages (DEVELOPMENT)"
-        depends on USB_GADGET && DEBUG_KERNEL
+        depends on DEBUG_KERNEL
         help
            Many controller and gadget drivers will print some debugging
            messages if you use this option to ask for those messages.
@@ -59,7 +59,7 @@ config USB_GADGET_DEBUG
 
 config USB_GADGET_DEBUG_FILES
         boolean "Debugging information files (DEVELOPMENT)"
-        depends on USB_GADGET && PROC_FS
+        depends on PROC_FS
         help
            Some of the drivers in the "gadget" framework can expose
            debugging information in files such as /proc/driver/udc
@@ -70,7 +70,7 @@ config USB_GADGET_DEBUG_FILES
 
 config USB_GADGET_DEBUG_FS
         boolean "Debugging information files in debugfs (DEVELOPMENT)"
-        depends on USB_GADGET && DEBUG_FS
+        depends on DEBUG_FS
         help
            Some of the drivers in the "gadget" framework can expose
            debugging information in files under /sys/kernel/debug/.
@@ -79,6 +79,23 @@ config USB_GADGET_DEBUG_FS
            Enable these files by choosing "Y" here.  If in doubt, or
            to conserve kernel memory, say "N".
 
+config USB_GADGET_VBUS_DRAW
+        int "Maximum VBUS Power usage (2-500 mA)"
+        range 2 500
+        default 2
+        help
+           Some devices need to draw power from USB when they are
+           configured, perhaps to operate circuitry or to recharge
+           batteries.  This is in addition to any local power supply,
+           such as an AC adapter or batteries.
+
+           Enter the maximum power your device draws through USB, in
+           milliAmperes.  The permitted range of values is 2 - 500 mA;
+           0 mA would be legal, but can make some hosts misbehave.
+
+           This value will be used except for system-specific gadget
+           drivers that have more specific information.
+
 config  USB_GADGET_SELECTED
         boolean
 
diff --git a/drivers/usb/gadget/cdc2.c b/drivers/usb/gadget/cdc2.c
index a724fc149850..5495b171cf29 100644
--- a/drivers/usb/gadget/cdc2.c
+++ b/drivers/usb/gadget/cdc2.c
@@ -155,7 +155,6 @@ static struct usb_configuration cdc_config_driver = {
         .bConfigurationValue    = 1,
         /* .iConfiguration = DYNAMIC */
         .bmAttributes           = USB_CONFIG_ATT_SELFPOWER,
-        .bMaxPower              = 1,    /* 2 mA, minimal */
 };
 
 /*-------------------------------------------------------------------------*/
diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index f79fdb839cb8..f2da0269e1b1 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -245,7 +245,7 @@ static int config_buf(struct usb_configuration *config,
         c->bConfigurationValue = config->bConfigurationValue;
         c->iConfiguration = config->iConfiguration;
         c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes;
-        c->bMaxPower = config->bMaxPower;
+        c->bMaxPower = config->bMaxPower ? : (CONFIG_USB_GADGET_VBUS_DRAW / 2);
 
         /* There may be e.g. OTG descriptors */
         if (config->descriptors) {
@@ -432,7 +432,7 @@ static int set_config(struct usb_composite_dev *cdev,
         }
 
         /* when we return, be sure our power usage is valid */
-        power = 2 * c->bMaxPower;
+        power = c->bMaxPower ? (2 * c->bMaxPower) : CONFIG_USB_GADGET_VBUS_DRAW;
 done:
         usb_gadget_vbus_draw(gadget, power);
         return result;
diff --git a/drivers/usb/gadget/ether.c b/drivers/usb/gadget/ether.c
index 944c8e889ab4..37252d0012a7 100644
--- a/drivers/usb/gadget/ether.c
+++ b/drivers/usb/gadget/ether.c
@@ -242,7 +242,6 @@ static struct usb_configuration rndis_config_driver = {
         .bConfigurationValue    = 2,
         /* .iConfiguration = DYNAMIC */
         .bmAttributes           = USB_CONFIG_ATT_SELFPOWER,
-        .bMaxPower              = 1,    /* 2 mA, minimal */
 };
 
 /*-------------------------------------------------------------------------*/
@@ -271,7 +270,6 @@ static struct usb_configuration eth_config_driver = {
         .bConfigurationValue    = 1,
         /* .iConfiguration = DYNAMIC */
         .bmAttributes           = USB_CONFIG_ATT_SELFPOWER,
-        .bMaxPower              = 1,    /* 2 mA, minimal */
 };
 
 /*-------------------------------------------------------------------------*/
diff --git a/drivers/usb/gadget/f_loopback.c b/drivers/usb/gadget/f_loopback.c
index 87dde012dacc..8affe1dfc2c1 100644
--- a/drivers/usb/gadget/f_loopback.c
+++ b/drivers/usb/gadget/f_loopback.c
@@ -352,7 +352,6 @@ static struct usb_configuration loopback_driver = {
         .bind           = loopback_bind_config,
         .bConfigurationValue = 2,
         .bmAttributes   = USB_CONFIG_ATT_SELFPOWER,
-        .bMaxPower      = 1,    /* 2 mA, minimal */
         /* .iConfiguration = DYNAMIC */
 };
 
diff --git a/drivers/usb/gadget/f_sourcesink.c b/drivers/usb/gadget/f_sourcesink.c
index f18c3a14d72a..dc84d26d2835 100644
--- a/drivers/usb/gadget/f_sourcesink.c
+++ b/drivers/usb/gadget/f_sourcesink.c
@@ -552,7 +552,6 @@ static struct usb_configuration sourcesink_driver = {
         .setup          = sourcesink_setup,
         .bConfigurationValue = 3,
         .bmAttributes   = USB_CONFIG_ATT_SELFPOWER,
-        .bMaxPower      = 1,    /* 2 mA, minimal */
         /* .iConfiguration = DYNAMIC */
 };
 
diff --git a/drivers/usb/gadget/file_storage.c b/drivers/usb/gadget/file_storage.c
index e0f616f39ba0..c4e62a6297d7 100644
--- a/drivers/usb/gadget/file_storage.c
+++ b/drivers/usb/gadget/file_storage.c
@@ -851,7 +851,7 @@ config_desc = {
         .bConfigurationValue =  CONFIG_VALUE,
         .iConfiguration =       STRING_CONFIG,
         .bmAttributes =         USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
-        .bMaxPower =            1,      // self-powered
+        .bMaxPower =            CONFIG_USB_GADGET_VBUS_DRAW / 2,
 };
 
 static struct usb_otg_descriptor
diff --git a/drivers/usb/gadget/gmidi.c b/drivers/usb/gadget/gmidi.c
index 6eee760410d6..60d3f9e9b51f 100644
--- a/drivers/usb/gadget/gmidi.c
+++ b/drivers/usb/gadget/gmidi.c
@@ -222,7 +222,7 @@ static struct usb_config_descriptor config_desc = {
          * power properties of the device. Is it selfpowered?
          */
         .bmAttributes =         USB_CONFIG_ATT_ONE,
-        .bMaxPower =            1,
+        .bMaxPower =            CONFIG_USB_GADGET_VBUS_DRAW / 2,
 };
 
 /* B.3.1  Standard AC Interface Descriptor */
diff --git a/drivers/usb/gadget/printer.c b/drivers/usb/gadget/printer.c
index 00b7ed5013a6..5a3034fdfe47 100644
--- a/drivers/usb/gadget/printer.c
+++ b/drivers/usb/gadget/printer.c
@@ -252,7 +252,7 @@ static struct usb_config_descriptor config_desc = {
         .bConfigurationValue =  DEV_CONFIG_VALUE,
         .iConfiguration =       0,
         .bmAttributes =         USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
-        .bMaxPower =            1       /* Self-Powered */
+        .bMaxPower =            CONFIG_USB_GADGET_VBUS_DRAW / 2,
 };
 
 static struct usb_interface_descriptor intf_desc = {
@@ -1476,7 +1476,6 @@ autoconf_fail:
         if (gadget->is_otg) {
                 otg_desc.bmAttributes |= USB_OTG_HNP,
                 config_desc.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
-                config_desc.bMaxPower = 4;
         }
 
         spin_lock_init(&dev->lock);
diff --git a/drivers/usb/gadget/serial.c b/drivers/usb/gadget/serial.c
index 2dee848b2f59..37879af1c433 100644
--- a/drivers/usb/gadget/serial.c
+++ b/drivers/usb/gadget/serial.c
@@ -159,7 +159,6 @@ static struct usb_configuration serial_config_driver = {
         /* .bConfigurationValue = f(use_acm) */
         /* .iConfiguration = DYNAMIC */
         .bmAttributes   = USB_CONFIG_ATT_SELFPOWER,
-        .bMaxPower      = 1,    /* 2 mA, minimal */
 };
 
 static int __init gs_bind(struct usb_composite_dev *cdev)