usb: gadget: move usb_gadget_controller_number() into a .c file and libcomposite

After I moved the function from the header file to the c file I see:

| $ size drivers/usb/gadget/gadget_chips.o
| text data bss dec hex filename
| 1048 0 0 1048 418 drivers/usb/gadget/gadget_chips.o

That is almost a KiB which is removed from each user.
As Felipe pointed out, the function / usage is very dumb actually. This is
used for the following reasons:
- epautoconf ep hint (could provide a per-gadget callback)
- miss-features. currently the missing altsetting on pxa's and something
ZLP related on musbhdrc (looks like an optimisation which could be
implemented in musb itself if it is correct)
- unique BCD accross all UDCs. Not sure how important this is.

Acked-by: Michal Nazarewicz <[e-mail]>
Signed-off-by: Sebastian Andrzej Siewior <[e-mail]>
Signed-off-by: Felipe Balbi <[e-mail]>

drivers/usb/gadget/Makefile

···
 
 obj-$(CONFIG_USB_GADGET)	+= udc-core.o
 obj-$(CONFIG_USB_LIBCOMPOSITE)	+= libcomposite.o
-libcomposite-y			:= usbstring.o config.o epautoconf.o
+libcomposite-y			:= usbstring.o config.o epautoconf.o gadget_chips.o
 obj-$(CONFIG_USB_DUMMY_HCD)	+= dummy_hcd.o
 obj-$(CONFIG_USB_NET2272)	+= net2272.o
 obj-$(CONFIG_USB_NET2280)	+= net2280.o

drivers/usb/gadget/gadget_chips.c

···
+/*
+ * USB device controllers have lots of quirks.  Use these macros in
+ * gadget drivers or other code that needs to deal with them, and which
+ * autoconfigures instead of using early binding to the hardware.
+ *
+ * This SHOULD eventually work like the ARM mach_is_*() stuff, driven by
+ * some config file that gets updated as new hardware is supported.
+ * (And avoiding all runtime comparisons in typical one-choice configs!)
+ *
+ * NOTE:  some of these controller drivers may not be available yet.
+ * Some are available on 2.4 kernels; several are available, but not
+ * yet pushed in the 2.6 mainline tree.
+ */
+
+#include <linux/usb/gadget.h>
+#include <linux/module.h>
+
+#include "gadget_chips.h"
+
+/**
+ * usb_gadget_controller_number - support bcdDevice id convention
+ * @gadget: the controller being driven
+ *
+ * Return a 2-digit BCD value associated with the peripheral controller,
+ * suitable for use as part of a bcdDevice value, or a negative error code.
+ *
+ * NOTE:  this convention is purely optional, and has no meaning in terms of
+ * any USB specification.  If you want to use a different convention in your
+ * gadget driver firmware -- maybe a more formal revision ID -- feel free.
+ *
+ * Hosts see these bcdDevice numbers, and are allowed (but not encouraged!)
+ * to change their behavior accordingly.  For example it might help avoiding
+ * some chip bug.
+ */
+int usb_gadget_controller_number(struct usb_gadget *gadget)
+{
+	if (gadget_is_net2280(gadget))
+		return 0x01;
+	else if (gadget_is_dummy(gadget))
+		return 0x02;
+	else if (gadget_is_pxa(gadget))
+		return 0x03;
+	else if (gadget_is_goku(gadget))
+		return 0x06;
+	else if (gadget_is_omap(gadget))
+		return 0x08;
+	else if (gadget_is_pxa27x(gadget))
+		return 0x11;
+	else if (gadget_is_s3c2410(gadget))
+		return 0x12;
+	else if (gadget_is_at91(gadget))
+		return 0x13;
+	else if (gadget_is_imx(gadget))
+		return 0x14;
+	else if (gadget_is_musbhdrc(gadget))
+		return 0x16;
+	else if (gadget_is_atmel_usba(gadget))
+		return 0x18;
+	else if (gadget_is_fsl_usb2(gadget))
+		return 0x19;
+	else if (gadget_is_amd5536udc(gadget))
+		return 0x20;
+	else if (gadget_is_m66592(gadget))
+		return 0x21;
+	else if (gadget_is_fsl_qe(gadget))
+		return 0x22;
+	else if (gadget_is_ci13xxx_pci(gadget))
+		return 0x23;
+	else if (gadget_is_langwell(gadget))
+		return 0x24;
+	else if (gadget_is_r8a66597(gadget))
+		return 0x25;
+	else if (gadget_is_s3c_hsotg(gadget))
+		return 0x26;
+	else if (gadget_is_pch(gadget))
+		return 0x27;
+	else if (gadget_is_ci13xxx_msm(gadget))
+		return 0x28;
+	else if (gadget_is_renesas_usbhs(gadget))
+		return 0x29;
+	else if (gadget_is_s3c_hsudc(gadget))
+		return 0x30;
+	else if (gadget_is_net2272(gadget))
+		return 0x31;
+	else if (gadget_is_dwc3(gadget))
+		return 0x32;
+	else if (gadget_is_lpc32xx(gadget))
+		return 0x33;
+	else if (gadget_is_bcm63xx(gadget))
+		return 0x34;
+
+	return -ENOENT;
+}
+EXPORT_SYMBOL_GPL(usb_gadget_controller_number);

drivers/usb/gadget/gadget_chips.h

···
 #define gadget_is_s3c_hsotg(g)		(!strcmp("s3c-hsotg", (g)->name))
 #define gadget_is_s3c_hsudc(g)		(!strcmp("s3c-hsudc", (g)->name))
 
-/**
- * usb_gadget_controller_number - support bcdDevice id convention
- * @gadget: the controller being driven
- *
- * Return a 2-digit BCD value associated with the peripheral controller,
- * suitable for use as part of a bcdDevice value, or a negative error code.
- *
- * NOTE:  this convention is purely optional, and has no meaning in terms of
- * any USB specification.  If you want to use a different convention in your
- * gadget driver firmware -- maybe a more formal revision ID -- feel free.
- *
- * Hosts see these bcdDevice numbers, and are allowed (but not encouraged!)
- * to change their behavior accordingly.  For example it might help avoiding
- * some chip bug.
- */
-static inline int usb_gadget_controller_number(struct usb_gadget *gadget)
-{
-	if (gadget_is_net2280(gadget))
-		return 0x01;
-	else if (gadget_is_dummy(gadget))
-		return 0x02;
-	else if (gadget_is_pxa(gadget))
-		return 0x03;
-	else if (gadget_is_goku(gadget))
-		return 0x06;
-	else if (gadget_is_omap(gadget))
-		return 0x08;
-	else if (gadget_is_pxa27x(gadget))
-		return 0x11;
-	else if (gadget_is_s3c2410(gadget))
-		return 0x12;
-	else if (gadget_is_at91(gadget))
-		return 0x13;
-	else if (gadget_is_imx(gadget))
-		return 0x14;
-	else if (gadget_is_musbhdrc(gadget))
-		return 0x16;
-	else if (gadget_is_atmel_usba(gadget))
-		return 0x18;
-	else if (gadget_is_fsl_usb2(gadget))
-		return 0x19;
-	else if (gadget_is_amd5536udc(gadget))
-		return 0x20;
-	else if (gadget_is_m66592(gadget))
-		return 0x21;
-	else if (gadget_is_fsl_qe(gadget))
-		return 0x22;
-	else if (gadget_is_ci13xxx_pci(gadget))
-		return 0x23;
-	else if (gadget_is_langwell(gadget))
-		return 0x24;
-	else if (gadget_is_r8a66597(gadget))
-		return 0x25;
-	else if (gadget_is_s3c_hsotg(gadget))
-		return 0x26;
-	else if (gadget_is_pch(gadget))
-		return 0x27;
-	else if (gadget_is_ci13xxx_msm(gadget))
-		return 0x28;
-	else if (gadget_is_renesas_usbhs(gadget))
-		return 0x29;
-	else if (gadget_is_s3c_hsudc(gadget))
-		return 0x30;
-	else if (gadget_is_net2272(gadget))
-		return 0x31;
-	else if (gadget_is_dwc3(gadget))
-		return 0x32;
-	else if (gadget_is_lpc32xx(gadget))
-		return 0x33;
-	else if (gadget_is_bcm63xx(gadget))
-		return 0x34;
-
-	return -ENOENT;
-}
-
+int usb_gadget_controller_number(struct usb_gadget *gadget);
 
 /**
  * gadget_supports_altsettings - return true if altsettings work