usb: gadget: nokia: Add mass storage driver to g_nokia

This patch adds removable mass storage support to g_nokia gadget (for N900).
It means that at runtime block device can be exported or unexported.
So it does not export anything by default and thus allows to use MyDocs
partition as before...

[ balbi@ti.com: make it build ]

Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/legacy/Kconfig

@@ -346,6 +346,7 @@ config USB_G_NOKIA
 	select USB_F_OBEX
 	select USB_F_PHONET
 	select USB_F_ECM
+	select USB_F_MASS_STORAGE
 	help
 	  The Nokia composite gadget provides support for acm, obex
 	  and phonet in only one composite gadget driver.

drivers/usb/gadget/legacy/nokia.c

@@ -24,6 +24,7 @@
 #include "u_phonet.h"
 #include "u_ecm.h"
 #include "gadget_chips.h"
+#include "f_mass_storage.h"
 
 /* Defines */
 
@@ -34,6 +35,29 @@ USB_GADGET_COMPOSITE_OPTIONS();
 
 USB_ETHERNET_MODULE_PARAMETERS();
 
+static struct fsg_module_parameters fsg_mod_data = {
+	.stall = 0,
+	.luns = 2,
+	.removable_count = 2,
+	.removable = { 1, 1, },
+};
+
+#ifdef CONFIG_USB_GADGET_DEBUG_FILES
+
+static unsigned int fsg_num_buffers = CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS;
+
+#else
+
+/*
+ * Number of buffers we will use.
+ * 2 is usually enough for good buffering pipeline
+ */
+#define fsg_num_buffers	CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS
+
+#endif /* CONFIG_USB_DEBUG */
+
+FSG_MODULE_PARAMETERS(/* no prefix */, fsg_mod_data);
+
 #define NOKIA_VENDOR_ID			0x0421	/* Nokia */
 #define NOKIA_PRODUCT_ID		0x01c8	/* Nokia Gadget */
 
@@ -94,6 +118,8 @@ static struct usb_function *f_obex1_cfg2;
 static struct usb_function *f_obex2_cfg2;
 static struct usb_function *f_phonet_cfg1;
 static struct usb_function *f_phonet_cfg2;
+static struct usb_function *f_msg_cfg1;
+static struct usb_function *f_msg_cfg2;
 
 
 static struct usb_configuration nokia_config_500ma_driver = {
@@ -117,6 +143,7 @@ static struct usb_function_instance *fi_ecm;
 static struct usb_function_instance *fi_obex1;
 static struct usb_function_instance *fi_obex2;
 static struct usb_function_instance *fi_phonet;
+static struct usb_function_instance *fi_msg;
 
 static int nokia_bind_config(struct usb_configuration *c)
 {
@@ -125,6 +152,8 @@ static int nokia_bind_config(struct usb_configuration *c)
 	struct usb_function *f_obex1 = NULL;
 	struct usb_function *f_ecm;
 	struct usb_function *f_obex2 = NULL;
+	struct usb_function *f_msg;
+	struct fsg_opts *fsg_opts;
 	int status = 0;
 	int obex1_stat = -1;
 	int obex2_stat = -1;
@@ -160,6 +189,12 @@ static int nokia_bind_config(struct usb_configuration *c)
 		goto err_get_ecm;
 	}
 
+	f_msg = usb_get_function(fi_msg);
+	if (IS_ERR(f_msg)) {
+		status = PTR_ERR(f_msg);
+		goto err_get_msg;
+	}
+
 	if (!IS_ERR_OR_NULL(f_phonet)) {
 		phonet_stat = usb_add_function(c, f_phonet);
 		if (phonet_stat)
@@ -187,21 +222,36 @@ static int nokia_bind_config(struct usb_configuration *c)
 		pr_debug("could not bind ecm config %d\n", status);
 		goto err_ecm;
 	}
+
+	fsg_opts = fsg_opts_from_func_inst(fi_msg);
+
+	status = fsg_common_run_thread(fsg_opts->common);
+	if (status)
+		goto err_msg;
+
+	status = usb_add_function(c, f_msg);
+	if (status)
+		goto err_msg;
+
 	if (c == &nokia_config_500ma_driver) {
 		f_acm_cfg1 = f_acm;
 		f_ecm_cfg1 = f_ecm;
 		f_phonet_cfg1 = f_phonet;
 		f_obex1_cfg1 = f_obex1;
 		f_obex2_cfg1 = f_obex2;
+		f_msg_cfg1 = f_msg;
 	} else {
 		f_acm_cfg2 = f_acm;
 		f_ecm_cfg2 = f_ecm;
 		f_phonet_cfg2 = f_phonet;
 		f_obex1_cfg2 = f_obex1;
 		f_obex2_cfg2 = f_obex2;
+		f_msg_cfg2 = f_msg;
 	}
 
 	return status;
+err_msg:
+	usb_remove_function(c, f_ecm);
 err_ecm:
 	usb_remove_function(c, f_acm);
 err_conf:
@@ -211,6 +261,8 @@ err_conf:
 		usb_remove_function(c, f_obex1);
 	if (!phonet_stat)
 		usb_remove_function(c, f_phonet);
+	usb_put_function(f_msg);
+err_get_msg:
 	usb_put_function(f_ecm);
 err_get_ecm:
 	usb_put_function(f_acm);
@@ -227,6 +279,8 @@ err_get_acm:
 static int nokia_bind(struct usb_composite_dev *cdev)
 {
 	struct usb_gadget	*gadget = cdev->gadget;
+	struct fsg_opts		*fsg_opts;
+	struct fsg_config	fsg_config;
 	int			status;
 
 	status = usb_string_ids_tab(cdev, strings_dev);
@@ -267,11 +321,46 @@ static int nokia_bind(struct usb_composite_dev *cdev)
 		goto err_acm_inst;
 	}
 
+	fi_msg = usb_get_function_instance("mass_storage");
+	if (IS_ERR(fi_msg)) {
+		status = PTR_ERR(fi_msg);
+		goto err_ecm_inst;
+	}
+
+	/* set up mass storage function */
+	fsg_config_from_params(&fsg_config, &fsg_mod_data, fsg_num_buffers);
+	fsg_config.vendor_name = "Nokia";
+	fsg_config.product_name = "N900";
+
+	fsg_opts = fsg_opts_from_func_inst(fi_msg);
+	fsg_opts->no_configfs = true;
+
+	status = fsg_common_set_num_buffers(fsg_opts->common, fsg_num_buffers);
+	if (status)
+		goto err_msg_inst;
+
+	status = fsg_common_set_nluns(fsg_opts->common, fsg_config.nluns);
+	if (status)
+		goto err_msg_buf;
+
+	status = fsg_common_set_cdev(fsg_opts->common, cdev, fsg_config.can_stall);
+	if (status)
+		goto err_msg_set_nluns;
+
+	fsg_common_set_sysfs(fsg_opts->common, true);
+
+	status = fsg_common_create_luns(fsg_opts->common, &fsg_config);
+	if (status)
+		goto err_msg_set_nluns;
+
+	fsg_common_set_inquiry_string(fsg_opts->common, fsg_config.vendor_name,
+				      fsg_config.product_name);
+
 	/* finally register the configuration */
 	status = usb_add_config(cdev, &nokia_config_500ma_driver,
 			nokia_bind_config);
 	if (status < 0)
-		goto err_ecm_inst;
+		goto err_msg_set_cdev;
 
 	status = usb_add_config(cdev, &nokia_config_100ma_driver,
 			nokia_bind_config);
@@ -292,6 +381,14 @@ err_put_cfg1:
 	if (!IS_ERR_OR_NULL(f_phonet_cfg1))
 		usb_put_function(f_phonet_cfg1);
 	usb_put_function(f_ecm_cfg1);
+err_msg_set_cdev:
+	fsg_common_remove_luns(fsg_opts->common);
+err_msg_set_nluns:
+	fsg_common_free_luns(fsg_opts->common);
+err_msg_buf:
+	fsg_common_free_buffers(fsg_opts->common);
+err_msg_inst:
+	usb_put_function_instance(fi_msg);
 err_ecm_inst:
 	usb_put_function_instance(fi_ecm);
 err_acm_inst:
@@ -325,7 +422,10 @@ static int nokia_unbind(struct usb_composite_dev *cdev)
 	usb_put_function(f_acm_cfg2);
 	usb_put_function(f_ecm_cfg1);
 	usb_put_function(f_ecm_cfg2);
+	usb_put_function(f_msg_cfg1);
+	usb_put_function(f_msg_cfg2);
 
+	usb_put_function_instance(fi_msg);
 	usb_put_function_instance(fi_ecm);
 	if (!IS_ERR(fi_obex2))
 		usb_put_function_instance(fi_obex2);