usb: gadget: f_uac1: convert to new function interface with backward compatibility

Converting uac1 to the new function interface requires converting
the USB uac1's function code and its users.

This patch converts the f_uac1.c to the new function interface.

The file is now compiled into a separate usb_f_uac1.ko module.

The old function interface is provided by means of a preprocessor
conditional directives. After all users are converted, the old interface
can be removed.

Tested-by: Sebastian Reimers <sebastian.reimers@googlemail.com>
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

6 files changed, 195 insertions, 31 deletions

diff --git a/drivers/usb/gadget/Kconfig b/drivers/usb/gadget/Kconfig
index ea8ebce60d8f..68302aa604be 100644
--- a/drivers/usb/gadget/Kconfig
+++ b/drivers/usb/gadget/Kconfig
@@ -181,6 +181,9 @@ config USB_F_MASS_STORAGE
 config USB_F_FS
         tristate
 
+config USB_F_UAC1
+        tristate
+
 config USB_F_UAC2
         tristate
 
diff --git a/drivers/usb/gadget/function/Makefile b/drivers/usb/gadget/function/Makefile
index 20775a87e51a..edb6dfa91932 100644
--- a/drivers/usb/gadget/function/Makefile
+++ b/drivers/usb/gadget/function/Makefile
@@ -32,5 +32,7 @@ usb_f_mass_storage-y		:= f_mass_storage.o storage_common.o
 obj-$(CONFIG_USB_F_MASS_STORAGE)+= usb_f_mass_storage.o
 usb_f_fs-y                      := f_fs.o
 obj-$(CONFIG_USB_F_FS)          += usb_f_fs.o
+usb_f_uac1-y                    := f_uac1.o u_uac1.o
+obj-$(CONFIG_USB_F_UAC1)        += usb_f_uac1.o
 usb_f_uac2-y                    := f_uac2.o
 obj-$(CONFIG_USB_F_UAC2)        += usb_f_uac2.o
diff --git a/drivers/usb/gadget/function/f_uac1.c b/drivers/usb/gadget/function/f_uac1.c
index 9cfaf1de7b90..787ed2bc4dd4 100644
--- a/drivers/usb/gadget/function/f_uac1.c
+++ b/drivers/usb/gadget/function/f_uac1.c
@@ -11,13 +11,17 @@
 
 #include <linux/slab.h>
 #include <linux/kernel.h>
+#include <linux/module.h>
 #include <linux/device.h>
 #include <linux/atomic.h>
 
 #include "u_uac1.h"
+#ifdef USBF_UAC1_INCLUDED
 #include "u_uac1.c"
+#endif
 
 #define OUT_EP_MAX_PACKET_SIZE  200
+#ifdef USBF_UAC1_INCLUDED
 static int req_buf_size = OUT_EP_MAX_PACKET_SIZE;
 module_param(req_buf_size, int, S_IRUGO);
 MODULE_PARM_DESC(req_buf_size, "ISO OUT endpoint request buffer size");
@@ -29,6 +33,7 @@ MODULE_PARM_DESC(req_count, "ISO OUT endpoint request count");
 static int audio_buf_size = 48000;
 module_param(audio_buf_size, int, S_IRUGO);
 MODULE_PARM_DESC(audio_buf_size, "Audio buffer size");
+#endif
 
 static int generic_set_cmd(struct usb_audio_control *con, u8 cmd, int value);
 static int generic_get_cmd(struct usb_audio_control *con, u8 cmd);
@@ -47,7 +52,7 @@ static int generic_get_cmd(struct usb_audio_control *con, u8 cmd);
 #define F_AUDIO_NUM_INTERFACES  2
 
 /* B.3.1  Standard AC Interface Descriptor */
-static struct usb_interface_descriptor ac_interface_desc __initdata = {
+static struct usb_interface_descriptor ac_interface_desc = {
         .bLength =              USB_DT_INTERFACE_SIZE,
         .bDescriptorType =      USB_DT_INTERFACE,
         .bNumEndpoints =        0,
@@ -189,7 +194,7 @@ static struct usb_endpoint_descriptor as_out_ep_desc  = {
 };
 
 /* Class-specific AS ISO OUT Endpoint Descriptor */
-static struct uac_iso_endpoint_descriptor as_iso_out_desc __initdata = {
+static struct uac_iso_endpoint_descriptor as_iso_out_desc = {
         .bLength =              UAC_ISO_ENDPOINT_DESC_SIZE,
         .bDescriptorType =      USB_DT_CS_ENDPOINT,
         .bDescriptorSubtype =   UAC_EP_GENERAL,
@@ -198,7 +203,7 @@ static struct uac_iso_endpoint_descriptor as_iso_out_desc __initdata = {
         .wLockDelay =           __constant_cpu_to_le16(1),
 };
 
-static struct usb_descriptor_header *f_audio_desc[] __initdata = {
+static struct usb_descriptor_header *f_audio_desc[] = {
         (struct usb_descriptor_header *)&ac_interface_desc,
         (struct usb_descriptor_header *)&ac_header_desc,
 
@@ -332,8 +337,17 @@ static int f_audio_out_ep_complete(struct usb_ep *ep, struct usb_request *req)
         struct f_audio *audio = req->context;
         struct usb_composite_dev *cdev = audio->card.func.config->cdev;
         struct f_audio_buf *copy_buf = audio->copy_buf;
+#ifndef USBF_UAC1_INCLUDED
+        struct f_uac1_opts *opts;
+        int audio_buf_size;
+#endif
         int err;
 
+#ifndef USBF_UAC1_INCLUDED
+        opts = container_of(audio->card.func.fi, struct f_uac1_opts,
+                            func_inst);
+        audio_buf_size = opts->audio_buf_size;
+#endif
         if (!copy_buf)
                 return -EINVAL;
 
@@ -578,10 +592,21 @@ static int f_audio_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
         struct usb_composite_dev *cdev = f->config->cdev;
         struct usb_ep *out_ep = audio->out_ep;
         struct usb_request *req;
+#ifndef USBF_UAC1_INCLUDED
+        struct f_uac1_opts *opts;
+        int req_buf_size, req_count, audio_buf_size;
+#endif
         int i = 0, err = 0;
 
         DBG(cdev, "intf %d, alt %d\n", intf, alt);
 
+#ifndef USBF_UAC1_INCLUDED
+        opts = container_of(f->fi, struct f_uac1_opts, func_inst);
+        req_buf_size = opts->req_buf_size;
+        req_count = opts->req_count;
+        audio_buf_size = opts->audio_buf_size;
+
+#endif
         if (intf == 1) {
                 if (alt == 1) {
                         usb_ep_enable(out_ep);
@@ -657,13 +682,50 @@ static void f_audio_build_desc(struct f_audio *audio)
 }
 
 /* audio function driver setup/binding */
-static int __init
+static int
 f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 {
         struct usb_composite_dev *cdev = c->cdev;
         struct f_audio          *audio = func_to_audio(f);
         int                     status;
         struct usb_ep           *ep = NULL;
+#ifndef USBF_UAC1_INCLUDED
+        struct f_uac1_opts      *audio_opts;
+
+        audio_opts = container_of(f->fi, struct f_uac1_opts, func_inst);
+        audio->card.gadget = c->cdev->gadget;
+        audio_opts->card = &audio->card;
+        /* set up ASLA audio devices */
+        if (!audio_opts->bound) {
+                status = gaudio_setup(&audio->card);
+                if (status < 0)
+                        return status;
+                audio_opts->bound = true;
+        }
+#else
+        audio->card.gadget = c->cdev->gadget;
+#endif
+        if (strings_uac1[0].id == 0) {
+                status = usb_string_ids_tab(c->cdev, strings_uac1);
+                if (status < 0)
+#ifdef USBF_UAC1_INCLUDED
+                        return status;
+#else
+                        goto fail;
+#endif
+                ac_interface_desc.iInterface = strings_uac1[STR_AC_IF].id;
+                input_terminal_desc.iTerminal =
+                        strings_uac1[STR_INPUT_TERMINAL].id;
+                input_terminal_desc.iChannelNames =
+                        strings_uac1[STR_INPUT_TERMINAL_CH_NAMES].id;
+                feature_unit_desc.iFeature = strings_uac1[STR_FEAT_DESC_0].id;
+                output_terminal_desc.iTerminal =
+                        strings_uac1[STR_OUTPUT_TERMINAL].id;
+                as_interface_alt_0_desc.iInterface =
+                        strings_uac1[STR_AS_IF_ALT0].id;
+                as_interface_alt_1_desc.iInterface =
+                        strings_uac1[STR_AS_IF_ALT1].id;
+        }
 
         f_audio_build_desc(audio);
 
@@ -698,19 +760,24 @@ f_audio_bind(struct usb_configuration *c, struct usb_function *f)
         return 0;
 
 fail:
+#ifndef USBF_UAC1_INCLUDED
+        gaudio_cleanup(&audio->card);
+#endif
         if (ep)
                 ep->driver_data = NULL;
         return status;
 }
 
+#ifdef USBF_UAC1_INCLUDED
 static void
-f_audio_unbind(struct usb_configuration *c, struct usb_function *f)
+old_f_audio_unbind(struct usb_configuration *c, struct usb_function *f)
 {
         struct f_audio          *audio = func_to_audio(f);
 
         usb_free_all_descriptors(f);
         kfree(audio);
 }
+#endif
 
 /*-------------------------------------------------------------------------*/
 
@@ -727,7 +794,7 @@ static int generic_get_cmd(struct usb_audio_control *con, u8 cmd)
 }
 
 /* Todo: add more control selecotor dynamically */
-static int __init control_selector_init(struct f_audio *audio)
+static int control_selector_init(struct f_audio *audio)
 {
         INIT_LIST_HEAD(&audio->cs);
         list_add(&feature_unit.list, &audio->cs);
@@ -744,6 +811,7 @@ static int __init control_selector_init(struct f_audio *audio)
         return 0;
 }
 
+#ifdef USBF_UAC1_INCLUDED
 /**
  * audio_bind_config - add USB audio function to a configuration
  * @c: the configuration to supcard the USB audio function
@@ -756,24 +824,6 @@ static int __init audio_bind_config(struct usb_configuration *c)
         struct f_audio *audio;
         int status;
 
-        if (strings_uac1[0].id == 0) {
-                status = usb_string_ids_tab(c->cdev, strings_uac1);
-                if (status < 0)
-                        return status;
-                ac_interface_desc.iInterface = strings_uac1[STR_AC_IF].id;
-                input_terminal_desc.iTerminal =
-                        strings_uac1[STR_INPUT_TERMINAL].id;
-                input_terminal_desc.iChannelNames =
-                        strings_uac1[STR_INPUT_TERMINAL_CH_NAMES].id;
-                feature_unit_desc.iFeature = strings_uac1[STR_FEAT_DESC_0].id;
-                output_terminal_desc.iTerminal =
-                        strings_uac1[STR_OUTPUT_TERMINAL].id;
-                as_interface_alt_0_desc.iInterface =
-                        strings_uac1[STR_AS_IF_ALT0].id;
-                as_interface_alt_1_desc.iInterface =
-                        strings_uac1[STR_AS_IF_ALT1].id;
-        }
-
         /* allocate and initialize one new instance */
         audio = kzalloc(sizeof *audio, GFP_KERNEL);
         if (!audio)
@@ -789,10 +839,9 @@ static int __init audio_bind_config(struct usb_configuration *c)
         status = gaudio_setup(&audio->card);
         if (status < 0)
                 goto setup_fail;
-
         audio->card.func.strings = uac1_strings;
         audio->card.func.bind = f_audio_bind;
-        audio->card.func.unbind = f_audio_unbind;
+        audio->card.func.unbind = old_f_audio_unbind;
         audio->card.func.set_alt = f_audio_set_alt;
         audio->card.func.setup = f_audio_setup;
         audio->card.func.disable = f_audio_disable;
@@ -816,3 +865,71 @@ setup_fail:
         kfree(audio);
         return status;
 }
+#else
+static void f_audio_free_inst(struct usb_function_instance *f)
+{
+        struct f_uac1_opts *opts;
+
+        opts = container_of(f, struct f_uac1_opts, func_inst);
+        gaudio_cleanup(opts->card);
+        kfree(opts);
+}
+
+static struct usb_function_instance *f_audio_alloc_inst(void)
+{
+        struct f_uac1_opts *opts;
+
+        opts = kzalloc(sizeof(*opts), GFP_KERNEL);
+        if (!opts)
+                return ERR_PTR(-ENOMEM);
+
+        opts->func_inst.free_func_inst = f_audio_free_inst;
+
+        return &opts->func_inst;
+}
+
+static void f_audio_free(struct usb_function *f)
+{
+        struct f_audio *audio = func_to_audio(f);
+
+        kfree(audio);
+}
+
+static void f_audio_unbind(struct usb_configuration *c, struct usb_function *f)
+{
+        usb_free_all_descriptors(f);
+}
+
+static struct usb_function *f_audio_alloc(struct usb_function_instance *fi)
+{
+        struct f_audio *audio;
+
+        /* allocate and initialize one new instance */
+        audio = kzalloc(sizeof(*audio), GFP_KERNEL);
+        if (!audio)
+                return ERR_PTR(-ENOMEM);
+
+        audio->card.func.name = "g_audio";
+
+        INIT_LIST_HEAD(&audio->play_queue);
+        spin_lock_init(&audio->lock);
+
+        audio->card.func.strings = uac1_strings;
+        audio->card.func.bind = f_audio_bind;
+        audio->card.func.unbind = f_audio_unbind;
+        audio->card.func.set_alt = f_audio_set_alt;
+        audio->card.func.setup = f_audio_setup;
+        audio->card.func.disable = f_audio_disable;
+        audio->card.func.free_func = f_audio_free;
+
+        control_selector_init(audio);
+
+        INIT_WORK(&audio->playback_work, f_audio_playback_work);
+
+        return &audio->card.func;
+}
+
+DECLARE_USB_FUNCTION_INIT(uac1, f_audio_alloc_inst, f_audio_alloc);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Bryan Wu");
+#endif
diff --git a/drivers/usb/gadget/function/u_uac1.c b/drivers/usb/gadget/function/u_uac1.c
index 7a55fea43430..9a55e5cf4cd8 100644
--- a/drivers/usb/gadget/function/u_uac1.c
+++ b/drivers/usb/gadget/function/u_uac1.c
@@ -10,6 +10,7 @@
  */
 
 #include <linux/kernel.h>
+#include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/device.h>
 #include <linux/delay.h>
@@ -23,6 +24,7 @@
  * This component encapsulates the ALSA devices for USB audio gadget
  */
 
+#ifdef USBF_UAC1_INCLUDED
 #define FILE_PCM_PLAYBACK       "/dev/snd/pcmC0D0p"
 #define FILE_PCM_CAPTURE        "/dev/snd/pcmC0D0c"
 #define FILE_CONTROL            "/dev/snd/controlC0"
@@ -38,7 +40,7 @@ MODULE_PARM_DESC(fn_cap, "Capture PCM device file name");
 static char *fn_cntl = FILE_CONTROL;
 module_param(fn_cntl, charp, S_IRUGO);
 MODULE_PARM_DESC(fn_cntl, "Control device file name");
-
+#endif
 /*-------------------------------------------------------------------------*/
 
 /**
@@ -167,7 +169,7 @@ static int playback_default_hw_params(struct gaudio_snd_dev *snd)
 /**
  * Playback audio buffer data by ALSA PCM device
  */
-static size_t u_audio_playback(struct gaudio *card, void *buf, size_t count)
+size_t u_audio_playback(struct gaudio *card, void *buf, size_t count)
 {
         struct gaudio_snd_dev   *snd = &card->playback;
         struct snd_pcm_substream *substream = snd->substream;
@@ -202,12 +204,12 @@ try_again:
         return 0;
 }
 
-static int u_audio_get_playback_channels(struct gaudio *card)
+int u_audio_get_playback_channels(struct gaudio *card)
 {
         return card->playback.channels;
 }
 
-static int u_audio_get_playback_rate(struct gaudio *card)
+int u_audio_get_playback_rate(struct gaudio *card)
 {
         return card->playback.rate;
 }
@@ -220,6 +222,15 @@ static int gaudio_open_snd_dev(struct gaudio *card)
 {
         struct snd_pcm_file *pcm_file;
         struct gaudio_snd_dev *snd;
+#ifndef USBF_UAC1_INCLUDED
+        struct f_uac1_opts *opts;
+        char *fn_play, *fn_cap, *fn_cntl;
+
+        opts = container_of(card->func.fi, struct f_uac1_opts, func_inst);
+        fn_play = opts->fn_play;
+        fn_cap = opts->fn_cap;
+        fn_cntl = opts->fn_cntl;
+#endif
 
         if (!card)
                 return -ENODEV;
@@ -293,7 +304,9 @@ static int gaudio_close_snd_dev(struct gaudio *gau)
         return 0;
 }
 
+#ifdef USBF_UAC1_INCLUDED
 static struct gaudio *the_card;
+#endif
 /**
  * gaudio_setup - setup ALSA interface and preparing for USB transfer
  *
@@ -301,15 +314,17 @@ static struct gaudio *the_card;
  *
  * Returns negative errno, or zero on success
  */
-int __init gaudio_setup(struct gaudio *card)
+int gaudio_setup(struct gaudio *card)
 {
         int     ret;
 
         ret = gaudio_open_snd_dev(card);
         if (ret)
                 ERROR(card, "we need at least one control device\n");
+#ifdef USBF_UAC1_INCLUDED
         else if (!the_card)
                 the_card = card;
+#endif
 
         return ret;
 
@@ -320,11 +335,17 @@ int __init gaudio_setup(struct gaudio *card)
  *
  * This is called to free all resources allocated by @gaudio_setup().
  */
+#ifdef USBF_UAC1_INCLUDED
 void gaudio_cleanup(void)
+#else
+void gaudio_cleanup(struct gaudio *the_card)
+#endif
 {
         if (the_card) {
                 gaudio_close_snd_dev(the_card);
+#ifdef USBF_UAC1_INCLUDED
                 the_card = NULL;
+#endif
         }
 }
 
diff --git a/drivers/usb/gadget/function/u_uac1.h b/drivers/usb/gadget/function/u_uac1.h
index 18c2e729faf6..5b4fe9efb8f1 100644
--- a/drivers/usb/gadget/function/u_uac1.h
+++ b/drivers/usb/gadget/function/u_uac1.h
@@ -50,7 +50,27 @@ struct gaudio {
         /* TODO */
 };
 
+struct f_uac1_opts {
+        struct usb_function_instance    func_inst;
+        int                             req_buf_size;
+        int                             req_count;
+        int                             audio_buf_size;
+        char                            *fn_play;
+        char                            *fn_cap;
+        char                            *fn_cntl;
+        bool                            bound;
+        struct gaudio                   *card;
+};
+
 int gaudio_setup(struct gaudio *card);
+#ifdef USBF_UAC1_INCLUDED
 void gaudio_cleanup(void);
+#else
+void gaudio_cleanup(struct gaudio *the_card);
+#endif
+
+size_t u_audio_playback(struct gaudio *card, void *buf, size_t count);
+int u_audio_get_playback_channels(struct gaudio *card);
+int u_audio_get_playback_rate(struct gaudio *card);
 
 #endif /* __U_AUDIO_H */
diff --git a/drivers/usb/gadget/legacy/audio.c b/drivers/usb/gadget/legacy/audio.c
index 47a7de71f7fb..cf1a5434feaf 100644
--- a/drivers/usb/gadget/legacy/audio.c
+++ b/drivers/usb/gadget/legacy/audio.c
@@ -80,6 +80,7 @@ static struct usb_function *f_uac2;
 #endif
 
 #ifdef CONFIG_GADGET_UAC1
+#define USBF_UAC1_INCLUDED
 #include "u_uac1.h"
 #include "f_uac1.c"
 #endif