usb: gadget: f_uac2: convert to new function interface with backward compatibility

Converting uac2 to the new function interface requires converting
the USB uac2's function code and its users.

This patch converts the f_uac2.c to the new function interface.

The file is now compiled into a separate usb_f_uac2.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>

5 files changed, 242 insertions, 40 deletions

diff --git a/drivers/usb/gadget/Kconfig b/drivers/usb/gadget/Kconfig
index 5c822afb6d70..ea8ebce60d8f 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_UAC2
+        tristate
+
 choice
         tristate "USB Gadget Drivers"
         default USB_ETH
diff --git a/drivers/usb/gadget/function/Makefile b/drivers/usb/gadget/function/Makefile
index 6d91f21b52a6..20775a87e51a 100644
--- a/drivers/usb/gadget/function/Makefile
+++ b/drivers/usb/gadget/function/Makefile
@@ -32,3 +32,5 @@ 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_uac2-y                    := f_uac2.o
+obj-$(CONFIG_USB_F_UAC2)        += usb_f_uac2.o
diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c
index 91615619c204..29b477fa2050 100644
--- a/drivers/usb/gadget/function/f_uac2.c
+++ b/drivers/usb/gadget/function/f_uac2.c
@@ -20,6 +20,10 @@
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
 
+#include "u_uac2.h"
+
+#ifdef USB_FUAC2_INCLUDED
+
 /* Playback(USB-IN) Default Stereo - Fl/Fr */
 static int p_chmask = 0x3;
 module_param(p_chmask, uint, S_IRUGO);
@@ -50,6 +54,8 @@ static int c_ssize = 2;
 module_param(c_ssize, uint, S_IRUGO);
 MODULE_PARM_DESC(c_ssize, "Capture Sample Size(bytes)");
 
+#endif
+
 /* Keep everyone on toes */
 #define USB_XFERS       2
 
@@ -340,6 +346,22 @@ static int uac2_pcm_open(struct snd_pcm_substream *substream)
 {
         struct snd_uac2_chip *uac2 = snd_pcm_substream_chip(substream);
         struct snd_pcm_runtime *runtime = substream->runtime;
+#ifndef USB_FUAC2_INCLUDED
+        struct audio_dev *audio_dev;
+        struct f_uac2_opts *opts;
+        int p_ssize, c_ssize;
+        int p_srate, c_srate;
+        int p_chmask, c_chmask;
+
+        audio_dev = uac2_to_agdev(uac2);
+        opts = container_of(audio_dev->func.fi, struct f_uac2_opts, func_inst);
+        p_ssize = opts->p_ssize;
+        c_ssize = opts->c_ssize;
+        p_srate = opts->p_srate;
+        c_srate = opts->c_srate;
+        p_chmask = opts->p_chmask;
+        c_chmask = opts->c_chmask;
+#endif
 
         runtime->hw = uac2_pcm_hardware;
 
@@ -409,7 +431,19 @@ static int snd_uac2_probe(struct platform_device *pdev)
         struct snd_uac2_chip *uac2 = pdev_to_uac2(pdev);
         struct snd_card *card;
         struct snd_pcm *pcm;
+#ifndef USB_FUAC2_INCLUDED
+        struct audio_dev *audio_dev;
+        struct f_uac2_opts *opts;
+#endif
         int err;
+#ifndef USB_FUAC2_INCLUDED
+        int p_chmask, c_chmask;
+
+        audio_dev = uac2_to_agdev(uac2);
+        opts = container_of(audio_dev->func.fi, struct f_uac2_opts, func_inst);
+        p_chmask = opts->p_chmask;
+        c_chmask = opts->c_chmask;
+#endif
 
         /* Choose any slot, with no id */
         err = snd_card_new(&pdev->dev, -1, NULL, THIS_MODULE, 0, &card);
@@ -917,7 +951,7 @@ free_ep(struct uac2_rtd_params *prm, struct usb_ep *ep)
                         "%s:%d Error!\n", __func__, __LINE__);
 }
 
-static int __init
+static int
 afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 {
         struct audio_dev *agdev = func_to_agdev(fn);
@@ -925,8 +959,50 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
         struct usb_composite_dev *cdev = cfg->cdev;
         struct usb_gadget *gadget = cdev->gadget;
         struct uac2_rtd_params *prm;
+#ifndef USB_FUAC2_INCLUDED
+        struct f_uac2_opts *uac2_opts;
+#endif
         int ret;
 
+#ifndef USB_FUAC2_INCLUDED
+        uac2_opts = container_of(fn->fi, struct f_uac2_opts, func_inst);
+#endif
+
+        ret = usb_string_ids_tab(cfg->cdev, strings_fn);
+        if (ret)
+                return ret;
+        iad_desc.iFunction = strings_fn[STR_ASSOC].id;
+        std_ac_if_desc.iInterface = strings_fn[STR_IF_CTRL].id;
+        in_clk_src_desc.iClockSource = strings_fn[STR_CLKSRC_IN].id;
+        out_clk_src_desc.iClockSource = strings_fn[STR_CLKSRC_OUT].id;
+        usb_out_it_desc.iTerminal = strings_fn[STR_USB_IT].id;
+        io_in_it_desc.iTerminal = strings_fn[STR_IO_IT].id;
+        usb_in_ot_desc.iTerminal = strings_fn[STR_USB_OT].id;
+        io_out_ot_desc.iTerminal = strings_fn[STR_IO_OT].id;
+        std_as_out_if0_desc.iInterface = strings_fn[STR_AS_OUT_ALT0].id;
+        std_as_out_if1_desc.iInterface = strings_fn[STR_AS_OUT_ALT1].id;
+        std_as_in_if0_desc.iInterface = strings_fn[STR_AS_IN_ALT0].id;
+        std_as_in_if1_desc.iInterface = strings_fn[STR_AS_IN_ALT1].id;
+
+#ifndef USB_FUAC2_INCLUDED
+        /* Initialize the configurable parameters */
+        usb_out_it_desc.bNrChannels = num_channels(uac2_opts->c_chmask);
+        usb_out_it_desc.bmChannelConfig = cpu_to_le32(uac2_opts->c_chmask);
+        io_in_it_desc.bNrChannels = num_channels(uac2_opts->p_chmask);
+        io_in_it_desc.bmChannelConfig = cpu_to_le32(uac2_opts->p_chmask);
+        as_out_hdr_desc.bNrChannels = num_channels(uac2_opts->c_chmask);
+        as_out_hdr_desc.bmChannelConfig = cpu_to_le32(uac2_opts->c_chmask);
+        as_in_hdr_desc.bNrChannels = num_channels(uac2_opts->p_chmask);
+        as_in_hdr_desc.bmChannelConfig = cpu_to_le32(uac2_opts->p_chmask);
+        as_out_fmt1_desc.bSubslotSize = uac2_opts->c_ssize;
+        as_out_fmt1_desc.bBitResolution = uac2_opts->c_ssize * 8;
+        as_in_fmt1_desc.bSubslotSize = uac2_opts->p_ssize;
+        as_in_fmt1_desc.bBitResolution = uac2_opts->p_ssize * 8;
+
+        snprintf(clksrc_in, sizeof(clksrc_in), "%uHz", uac2_opts->p_srate);
+        snprintf(clksrc_out, sizeof(clksrc_out), "%uHz", uac2_opts->c_srate);
+#endif
+
         ret = usb_interface_id(cfg, fn);
         if (ret < 0) {
                 dev_err(&uac2->pdev.dev,
@@ -1018,28 +1094,6 @@ err:
         return -EINVAL;
 }
 
-static void
-afunc_unbind(struct usb_configuration *cfg, struct usb_function *fn)
-{
-        struct audio_dev *agdev = func_to_agdev(fn);
-        struct uac2_rtd_params *prm;
-
-        alsa_uac2_exit(agdev);
-
-        prm = &agdev->uac2.p_prm;
-        kfree(prm->rbuf);
-
-        prm = &agdev->uac2.c_prm;
-        kfree(prm->rbuf);
-        usb_free_all_descriptors(fn);
-
-        if (agdev->in_ep)
-                agdev->in_ep->driver_data = NULL;
-        if (agdev->out_ep)
-                agdev->out_ep->driver_data = NULL;
-        kfree(agdev);
-}
-
 static int
 afunc_set_alt(struct usb_function *fn, unsigned intf, unsigned alt)
 {
@@ -1163,12 +1217,22 @@ in_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
         struct usb_request *req = fn->config->cdev->req;
         struct audio_dev *agdev = func_to_agdev(fn);
         struct snd_uac2_chip *uac2 = &agdev->uac2;
+#ifndef USB_FUAC2_INCLUDED
+        struct f_uac2_opts *opts;
+#endif
         u16 w_length = le16_to_cpu(cr->wLength);
         u16 w_index = le16_to_cpu(cr->wIndex);
         u16 w_value = le16_to_cpu(cr->wValue);
         u8 entity_id = (w_index >> 8) & 0xff;
         u8 control_selector = w_value >> 8;
         int value = -EOPNOTSUPP;
+#ifndef USB_FUAC2_INCLUDED
+        int p_srate, c_srate;
+
+        opts = container_of(agdev->func.fi, struct f_uac2_opts, func_inst);
+        p_srate = opts->p_srate;
+        c_srate = opts->c_srate;
+#endif
 
         if (control_selector == UAC2_CS_CONTROL_SAM_FREQ) {
                 struct cntrl_cur_lay3 c;
@@ -1198,6 +1262,9 @@ in_rq_range(struct usb_function *fn, const struct usb_ctrlrequest *cr)
         struct usb_request *req = fn->config->cdev->req;
         struct audio_dev *agdev = func_to_agdev(fn);
         struct snd_uac2_chip *uac2 = &agdev->uac2;
+#ifndef USB_FUAC2_INCLUDED
+        struct f_uac2_opts *opts;
+#endif
         u16 w_length = le16_to_cpu(cr->wLength);
         u16 w_index = le16_to_cpu(cr->wIndex);
         u16 w_value = le16_to_cpu(cr->wValue);
@@ -1205,6 +1272,13 @@ in_rq_range(struct usb_function *fn, const struct usb_ctrlrequest *cr)
         u8 control_selector = w_value >> 8;
         struct cntrl_range_lay3 r;
         int value = -EOPNOTSUPP;
+#ifndef USB_FUAC2_INCLUDED
+        int p_srate, c_srate;
+
+        opts = container_of(agdev->func.fi, struct f_uac2_opts, func_inst);
+        p_srate = opts->p_srate;
+        c_srate = opts->c_srate;
+#endif
 
         if (control_selector == UAC2_CS_CONTROL_SAM_FREQ) {
                 if (entity_id == USB_IN_CLK_ID)
@@ -1308,6 +1382,30 @@ afunc_setup(struct usb_function *fn, const struct usb_ctrlrequest *cr)
         return value;
 }
 
+#ifdef USB_FUAC2_INCLUDED
+
+static void
+old_afunc_unbind(struct usb_configuration *cfg, struct usb_function *fn)
+{
+        struct audio_dev *agdev = func_to_agdev(fn);
+        struct uac2_rtd_params *prm;
+
+        alsa_uac2_exit(agdev);
+
+        prm = &agdev->uac2.p_prm;
+        kfree(prm->rbuf);
+
+        prm = &agdev->uac2.c_prm;
+        kfree(prm->rbuf);
+        usb_free_all_descriptors(fn);
+
+        if (agdev->in_ep)
+                agdev->in_ep->driver_data = NULL;
+        if (agdev->out_ep)
+                agdev->out_ep->driver_data = NULL;
+        kfree(agdev);
+}
+
 static int audio_bind_config(struct usb_configuration *cfg)
 {
         struct audio_dev *agdev;
@@ -1317,26 +1415,10 @@ static int audio_bind_config(struct usb_configuration *cfg)
         if (agdev == NULL)
                 return -ENOMEM;
 
-        res = usb_string_ids_tab(cfg->cdev, strings_fn);
-        if (res)
-                return res;
-        iad_desc.iFunction = strings_fn[STR_ASSOC].id;
-        std_ac_if_desc.iInterface = strings_fn[STR_IF_CTRL].id;
-        in_clk_src_desc.iClockSource = strings_fn[STR_CLKSRC_IN].id;
-        out_clk_src_desc.iClockSource = strings_fn[STR_CLKSRC_OUT].id;
-        usb_out_it_desc.iTerminal = strings_fn[STR_USB_IT].id;
-        io_in_it_desc.iTerminal = strings_fn[STR_IO_IT].id;
-        usb_in_ot_desc.iTerminal = strings_fn[STR_USB_OT].id;
-        io_out_ot_desc.iTerminal = strings_fn[STR_IO_OT].id;
-        std_as_out_if0_desc.iInterface = strings_fn[STR_AS_OUT_ALT0].id;
-        std_as_out_if1_desc.iInterface = strings_fn[STR_AS_OUT_ALT1].id;
-        std_as_in_if0_desc.iInterface = strings_fn[STR_AS_IN_ALT0].id;
-        std_as_in_if1_desc.iInterface = strings_fn[STR_AS_IN_ALT1].id;
-
         agdev->func.name = "uac2_func";
         agdev->func.strings = fn_strings;
         agdev->func.bind = afunc_bind;
-        agdev->func.unbind = afunc_unbind;
+        agdev->func.unbind = old_afunc_unbind;
         agdev->func.set_alt = afunc_set_alt;
         agdev->func.get_alt = afunc_get_alt;
         agdev->func.disable = afunc_disable;
@@ -1365,3 +1447,85 @@ static int audio_bind_config(struct usb_configuration *cfg)
 
         return res;
 }
+
+#else
+
+static void afunc_free_inst(struct usb_function_instance *f)
+{
+        struct f_uac2_opts *opts;
+
+        opts = container_of(f, struct f_uac2_opts, func_inst);
+        kfree(opts);
+}
+
+static struct usb_function_instance *afunc_alloc_inst(void)
+{
+        struct f_uac2_opts *opts;
+
+        opts = kzalloc(sizeof(*opts), GFP_KERNEL);
+        if (!opts)
+                return ERR_PTR(-ENOMEM);
+
+        opts->func_inst.free_func_inst = afunc_free_inst;
+
+        return &opts->func_inst;
+}
+
+static void afunc_free(struct usb_function *f)
+{
+        struct audio_dev *agdev;
+
+        agdev = func_to_agdev(f);
+        kfree(agdev);
+}
+
+static void afunc_unbind(struct usb_configuration *c, struct usb_function *f)
+{
+        struct audio_dev *agdev = func_to_agdev(f);
+        struct uac2_rtd_params *prm;
+
+        alsa_uac2_exit(agdev);
+
+        prm = &agdev->uac2.p_prm;
+        kfree(prm->rbuf);
+
+        prm = &agdev->uac2.c_prm;
+        kfree(prm->rbuf);
+        usb_free_all_descriptors(f);
+
+        if (agdev->in_ep)
+                agdev->in_ep->driver_data = NULL;
+        if (agdev->out_ep)
+                agdev->out_ep->driver_data = NULL;
+}
+
+struct usb_function *afunc_alloc(struct usb_function_instance *fi)
+{
+        struct audio_dev *agdev;
+        struct f_uac2_opts *opts;
+
+        agdev = kzalloc(sizeof(*agdev), GFP_KERNEL);
+        if (agdev == NULL)
+                return ERR_PTR(-ENOMEM);
+
+        opts = container_of(fi, struct f_uac2_opts, func_inst);
+
+        agdev->func.name = "uac2_func";
+        agdev->func.strings = fn_strings;
+        agdev->func.bind = afunc_bind;
+        agdev->func.unbind = afunc_unbind;
+        agdev->func.set_alt = afunc_set_alt;
+        agdev->func.get_alt = afunc_get_alt;
+        agdev->func.disable = afunc_disable;
+        agdev->func.setup = afunc_setup;
+        agdev->func.free_func = afunc_free;
+
+        return &agdev->func;
+}
+
+DECLARE_USB_FUNCTION_INIT(uac2, afunc_alloc_inst, afunc_alloc);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Yadwinder Singh");
+MODULE_AUTHOR("Jaswinder Singh");
+
+#endif
diff --git a/drivers/usb/gadget/function/u_uac2.h b/drivers/usb/gadget/function/u_uac2.h
new file mode 100644
index 000000000000..290b83af1b69
--- /dev/null
+++ b/drivers/usb/gadget/function/u_uac2.h
@@ -0,0 +1,32 @@
+/*
+ * u_uac2.h
+ *
+ * Utility definitions for UAC2 function
+ *
+ * Copyright (c) 2014 Samsung Electronics Co., Ltd.
+ *              http://www.samsung.com
+ *
+ * Author: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef U_UAC2_H
+#define U_UAC2_H
+
+#include <linux/usb/composite.h>
+
+struct f_uac2_opts {
+        struct usb_function_instance    func_inst;
+        int                             p_chmask;
+        int                             p_srate;
+        int                             p_ssize;
+        int                             c_chmask;
+        int                             c_srate;
+        int                             c_ssize;
+        bool                            bound;
+};
+
+#endif
diff --git a/drivers/usb/gadget/legacy/audio.c b/drivers/usb/gadget/legacy/audio.c
index 3c2328316c05..a41316bb436a 100644
--- a/drivers/usb/gadget/legacy/audio.c
+++ b/drivers/usb/gadget/legacy/audio.c
@@ -45,6 +45,7 @@ static struct usb_gadget_strings *audio_strings[] = {
 #include "u_uac1.c"
 #include "f_uac1.c"
 #else
+#define USB_FUAC2_INCLUDED
 #include "f_uac2.c"
 #endif