Re: [PATCH 2/4] usb: gadget: f_midi: defaults buflen sizes to 512

[Felipe Ferreri Tonello]

Hi Balbi,

On 10/08/16 12:25, Felipe Balbi wrote:
> 
> Hi,
> 
> "Felipe F. Tonello"  writes:
>> 512 is the value used by wMaxPacketSize, as specified by the USB Spec. This
> 
> this is only true for HS :-) FS and SS use different sizes. Do you want
> to use 1024 (SS maxp) by default instead? Then all speeds will have this
> working out just fine.

That's true, altough I've never seen a FS or SS device with MIDI gadget,
they are all 1.1 or 2.0 max.

Nevertheless, your suggestion really makes sense since it will work in
any situation.

-- 
Felipe


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Re: [PATCH 2/4] usb: gadget: f_midi: defaults buflen sizes to 512

[Felipe Balbi]

Hi,

"Felipe F. Tonello"  writes:
> 512 is the value used by wMaxPacketSize, as specified by the USB Spec. This

this is only true for HS :-) FS and SS use different sizes. Do you want
to use 1024 (SS maxp) by default instead? Then all speeds will have this
working out just fine.

-- 
balbi


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[PATCH 2/4] usb: gadget: f_midi: defaults buflen sizes to 512

[Felipe F. Tonello]

512 is the value used by wMaxPacketSize, as specified by the USB Spec. This
makes sure this driver uses, by default, the most optimal value for IN and OUT
endpoint requests.

Signed-off-by: Felipe F. Tonello 
---
 drivers/usb/gadget/function/f_midi.c | 2 +-
 drivers/usb/gadget/legacy/gmidi.c| 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/gadget/function/f_midi.c 
b/drivers/usb/gadget/function/f_midi.c
index a83d852b1da5..dd5cca6eae7c 100644
--- a/drivers/usb/gadget/function/f_midi.c
+++ b/drivers/usb/gadget/function/f_midi.c
@@ -1123,7 +1123,7 @@ static struct usb_function_instance 
*f_midi_alloc_inst(void)
opts->func_inst.free_func_inst = f_midi_free_inst;
opts->index = SNDRV_DEFAULT_IDX1;
opts->id = SNDRV_DEFAULT_STR1;
-   opts->buflen = 256;
+   opts->buflen = 512;
opts->qlen = 32;
opts->in_ports = 1;
opts->out_ports = 1;
diff --git a/drivers/usb/gadget/legacy/gmidi.c 
b/drivers/usb/gadget/legacy/gmidi.c
index fc2ac150f5ff..0bf39c3ccdb1 100644
--- a/drivers/usb/gadget/legacy/gmidi.c
+++ b/drivers/usb/gadget/legacy/gmidi.c
@@ -47,7 +47,7 @@ static char *id = SNDRV_DEFAULT_STR1;
 module_param(id, charp, S_IRUGO);
 MODULE_PARM_DESC(id, "ID string for the USB MIDI Gadget adapter.");
 
-static unsigned int buflen = 256;
+static unsigned int buflen = 512;
 module_param(buflen, uint, S_IRUGO);
 MODULE_PARM_DESC(buflen, "MIDI buffer length");
 
-- 
2.9.2