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path: root/drivers/usb/gadget/function/f_midi.c
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Diffstat (limited to 'drivers/usb/gadget/function/f_midi.c')
-rw-r--r--drivers/usb/gadget/function/f_midi.c200
1 files changed, 92 insertions, 108 deletions
diff --git a/drivers/usb/gadget/function/f_midi.c b/drivers/usb/gadget/function/f_midi.c
index fb1fe96d3215..84c0ee5ebd1e 100644
--- a/drivers/usb/gadget/function/f_midi.c
+++ b/drivers/usb/gadget/function/f_midi.c
@@ -56,7 +56,7 @@ static const char f_midi_longname[] = "MIDI Gadget";
* USB <- IN endpoint <- rawmidi
*/
struct gmidi_in_port {
- struct f_midi *midi;
+ struct snd_rawmidi_substream *substream;
int active;
uint8_t cable;
uint8_t state;
@@ -78,9 +78,7 @@ struct f_midi {
struct snd_rawmidi *rmidi;
u8 ms_id;
- struct snd_rawmidi_substream *in_substream[MAX_PORTS];
struct snd_rawmidi_substream *out_substream[MAX_PORTS];
- struct gmidi_in_port *in_port[MAX_PORTS];
unsigned long out_triggered;
struct tasklet_struct tasklet;
@@ -92,6 +90,8 @@ struct f_midi {
/* This fifo is used as a buffer ring for pre-allocated IN usb_requests */
DECLARE_KFIFO_PTR(in_req_fifo, struct usb_request *);
unsigned int in_last_port;
+
+ struct gmidi_in_port in_ports_array[/* in_ports */];
};
static inline struct f_midi *func_to_midi(struct usb_function *f)
@@ -518,98 +518,95 @@ static void f_midi_drop_out_substreams(struct f_midi *midi)
{
unsigned int i;
- for (i = 0; i < MAX_PORTS; i++) {
- struct gmidi_in_port *port = midi->in_port[i];
- struct snd_rawmidi_substream *substream = midi->in_substream[i];
-
- if (!port)
- break;
-
- if (!port->active || !substream)
- continue;
-
- snd_rawmidi_drop_output(substream);
+ for (i = 0; i < midi->in_ports; i++) {
+ struct gmidi_in_port *port = midi->in_ports_array + i;
+ struct snd_rawmidi_substream *substream = port->substream;
+ if (port->active && substream)
+ snd_rawmidi_drop_output(substream);
}
}
-static void f_midi_transmit(struct f_midi *midi)
+static int f_midi_do_transmit(struct f_midi *midi, struct usb_ep *ep)
{
- struct usb_ep *ep = midi->in_ep;
- bool active;
-
- /* We only care about USB requests if IN endpoint is enabled */
- if (!ep || !ep->enabled)
- goto drop_out;
+ struct usb_request *req = NULL;
+ unsigned int len, i;
+ bool active = false;
+ int err;
- do {
- struct usb_request *req = NULL;
- unsigned int len, i;
+ /*
+ * We peek the request in order to reuse it if it fails to enqueue on
+ * its endpoint
+ */
+ len = kfifo_peek(&midi->in_req_fifo, &req);
+ if (len != 1) {
+ ERROR(midi, "%s: Couldn't get usb request\n", __func__);
+ return -1;
+ }
- active = false;
+ /*
+ * If buffer overrun, then we ignore this transmission.
+ * IMPORTANT: This will cause the user-space rawmidi device to block
+ * until a) usb requests have been completed or b) snd_rawmidi_write()
+ * times out.
+ */
+ if (req->length > 0)
+ return 0;
- /* We peek the request in order to reuse it if it fails
- * to enqueue on its endpoint */
- len = kfifo_peek(&midi->in_req_fifo, &req);
- if (len != 1) {
- ERROR(midi, "%s: Couldn't get usb request\n", __func__);
- goto drop_out;
- }
+ for (i = midi->in_last_port; i < midi->in_ports; ++i) {
+ struct gmidi_in_port *port = midi->in_ports_array + i;
+ struct snd_rawmidi_substream *substream = port->substream;
- /* If buffer overrun, then we ignore this transmission.
- * IMPORTANT: This will cause the user-space rawmidi device to block until a) usb
- * requests have been completed or b) snd_rawmidi_write() times out. */
- if (req->length > 0)
- return;
+ if (!port->active || !substream)
+ continue;
- for (i = midi->in_last_port; i < MAX_PORTS; i++) {
- struct gmidi_in_port *port = midi->in_port[i];
- struct snd_rawmidi_substream *substream = midi->in_substream[i];
+ while (req->length + 3 < midi->buflen) {
+ uint8_t b;
- if (!port) {
- /* Reset counter when we reach the last available port */
- midi->in_last_port = 0;
+ if (snd_rawmidi_transmit(substream, &b, 1) != 1) {
+ port->active = 0;
break;
}
+ f_midi_transmit_byte(req, port, b);
+ }
- if (!port->active || !substream)
- continue;
+ active = !!port->active;
+ if (active)
+ break;
+ }
+ midi->in_last_port = active ? i : 0;
- while (req->length + 3 < midi->buflen) {
- uint8_t b;
+ if (req->length <= 0)
+ goto done;
- if (snd_rawmidi_transmit(substream, &b, 1) != 1) {
- port->active = 0;
- break;
- }
- f_midi_transmit_byte(req, port, b);
- }
+ err = usb_ep_queue(ep, req, GFP_ATOMIC);
+ if (err < 0) {
+ ERROR(midi, "%s failed to queue req: %d\n",
+ midi->in_ep->name, err);
+ req->length = 0; /* Re-use request next time. */
+ } else {
+ /* Upon success, put request at the back of the queue. */
+ kfifo_skip(&midi->in_req_fifo);
+ kfifo_put(&midi->in_req_fifo, req);
+ }
- active = !!port->active;
- /* Check if last port is still active, which means that
- * there is still data on that substream but this current
- * request run out of space. */
- if (active) {
- midi->in_last_port = i;
- /* There is no need to re-iterate though midi ports. */
- break;
- }
- }
+done:
+ return active;
+}
- if (req->length > 0) {
- int err;
+static void f_midi_transmit(struct f_midi *midi)
+{
+ struct usb_ep *ep = midi->in_ep;
+ int ret;
- err = usb_ep_queue(ep, req, GFP_ATOMIC);
- if (err < 0) {
- ERROR(midi, "%s failed to queue req: %d\n",
- midi->in_ep->name, err);
- req->length = 0; /* Re-use request next time. */
- } else {
- /* Upon success, put request at the back of the queue. */
- kfifo_skip(&midi->in_req_fifo);
- kfifo_put(&midi->in_req_fifo, req);
- }
- }
- } while (active);
+ /* We only care about USB requests if IN endpoint is enabled */
+ if (!ep || !ep->enabled)
+ goto drop_out;
+
+ do {
+ ret = f_midi_do_transmit(midi, ep);
+ if (ret < 0)
+ goto drop_out;
+ } while (ret);
return;
@@ -626,13 +623,15 @@ static void f_midi_in_tasklet(unsigned long data)
static int f_midi_in_open(struct snd_rawmidi_substream *substream)
{
struct f_midi *midi = substream->rmidi->private_data;
+ struct gmidi_in_port *port;
- if (!midi->in_port[substream->number])
+ if (substream->number >= midi->in_ports)
return -EINVAL;
VDBG(midi, "%s()\n", __func__);
- midi->in_substream[substream->number] = substream;
- midi->in_port[substream->number]->state = STATE_UNKNOWN;
+ port = midi->in_ports_array + substream->number;
+ port->substream = substream;
+ port->state = STATE_UNKNOWN;
return 0;
}
@@ -648,11 +647,11 @@ static void f_midi_in_trigger(struct snd_rawmidi_substream *substream, int up)
{
struct f_midi *midi = substream->rmidi->private_data;
- if (!midi->in_port[substream->number])
+ if (substream->number >= midi->in_ports)
return;
VDBG(midi, "%s() %d\n", __func__, up);
- midi->in_port[substream->number]->active = up;
+ midi->in_ports_array[substream->number].active = up;
if (up)
tasklet_hi_schedule(&midi->tasklet);
}
@@ -1128,14 +1127,11 @@ static void f_midi_free(struct usb_function *f)
{
struct f_midi *midi;
struct f_midi_opts *opts;
- int i;
midi = func_to_midi(f);
opts = container_of(f->fi, struct f_midi_opts, func_inst);
kfree(midi->id);
mutex_lock(&opts->lock);
- for (i = opts->in_ports - 1; i >= 0; --i)
- kfree(midi->in_port[i]);
kfifo_free(&midi->in_req_fifo);
kfree(midi);
--opts->refcnt;
@@ -1163,7 +1159,7 @@ static void f_midi_unbind(struct usb_configuration *c, struct usb_function *f)
static struct usb_function *f_midi_alloc(struct usb_function_instance *fi)
{
- struct f_midi *midi;
+ struct f_midi *midi = NULL;
struct f_midi_opts *opts;
int status, i;
@@ -1172,37 +1168,26 @@ static struct usb_function *f_midi_alloc(struct usb_function_instance *fi)
mutex_lock(&opts->lock);
/* sanity check */
if (opts->in_ports > MAX_PORTS || opts->out_ports > MAX_PORTS) {
- mutex_unlock(&opts->lock);
- return ERR_PTR(-EINVAL);
+ status = -EINVAL;
+ goto setup_fail;
}
/* allocate and initialize one new instance */
- midi = kzalloc(sizeof(*midi), GFP_KERNEL);
+ midi = kzalloc(
+ sizeof(*midi) + opts->in_ports * sizeof(*midi->in_ports_array),
+ GFP_KERNEL);
if (!midi) {
- mutex_unlock(&opts->lock);
- return ERR_PTR(-ENOMEM);
+ status = -ENOMEM;
+ goto setup_fail;
}
- for (i = 0; i < opts->in_ports; i++) {
- struct gmidi_in_port *port = kzalloc(sizeof(*port), GFP_KERNEL);
-
- if (!port) {
- status = -ENOMEM;
- mutex_unlock(&opts->lock);
- goto setup_fail;
- }
-
- port->midi = midi;
- port->active = 0;
- port->cable = i;
- midi->in_port[i] = port;
- }
+ for (i = 0; i < opts->in_ports; i++)
+ midi->in_ports_array[i].cable = i;
/* set up ALSA midi devices */
midi->id = kstrdup(opts->id, GFP_KERNEL);
if (opts->id && !midi->id) {
status = -ENOMEM;
- mutex_unlock(&opts->lock);
goto setup_fail;
}
midi->in_ports = opts->in_ports;
@@ -1229,8 +1214,7 @@ static struct usb_function *f_midi_alloc(struct usb_function_instance *fi)
return &midi->func;
setup_fail:
- for (--i; i >= 0; i--)
- kfree(midi->in_port[i]);
+ mutex_unlock(&opts->lock);
kfree(midi);
return ERR_PTR(status);
}