On Sat, 23 May 2020 19:49:57 +0200, Vasily Khoruzhick wrote: > > Add hw monitor volume control for POD HD500. The same change may > work for HD500X but I don't have it to test. > > Signed-off-by: Vasily Khoruzhick <anarsoul@xxxxxxxxx> > --- > v2: clamp volume value to [0, ARRAY_SIZE() -1] in > podhd_set_monitor_level() Thanks for the patch. The basic implementation looks good, but I see a few issues. Below are the comments: > @@ -132,6 +132,7 @@ static int line6_send_raw_message(struct usb_line6 *line6, const char *buffer, > > return done; > } > +EXPORT_SYMBOL(line6_send_raw_message); Let's use EXPORT_SYMBOL_GPL() instead. > +static const unsigned int float_zero_to_one_lookup[] = { > +0x00000000, 0x3C23D70A, 0x3CA3D70A, 0x3CF5C28F, 0x3D23D70A, 0x3D4CCCCD, > +0x3D75C28F, 0x3D8F5C29, 0x3DA3D70A, 0x3DB851EC, 0x3DCCCCCD, 0x3DE147AE, > +0x3DF5C28F, 0x3E051EB8, 0x3E0F5C29, 0x3E19999A, 0x3E23D70A, 0x3E2E147B, > +0x3E3851EC, 0x3E428F5C, 0x3E4CCCCD, 0x3E570A3D, 0x3E6147AE, 0x3E6B851F, > +0x3E75C28F, 0x3E800000, 0x3E851EB8, 0x3E8A3D71, 0x3E8F5C29, 0x3E947AE1, > +0x3E99999A, 0x3E9EB852, 0x3EA3D70A, 0x3EA8F5C3, 0x3EAE147B, 0x3EB33333, > +0x3EB851EC, 0x3EBD70A4, 0x3EC28F5C, 0x3EC7AE14, 0x3ECCCCCD, 0x3ED1EB85, > +0x3ED70A3D, 0x3EDC28F6, 0x3EE147AE, 0x3EE66666, 0x3EEB851F, 0x3EF0A3D7, > +0x3EF5C28F, 0x3EFAE148, 0x3F000000, 0x3F028F5C, 0x3F051EB8, 0x3F07AE14, > +0x3F0A3D71, 0x3F0CCCCD, 0x3F0F5C29, 0x3F11EB85, 0x3F147AE1, 0x3F170A3D, > +0x3F19999A, 0x3F1C28F6, 0x3F1EB852, 0x3F2147AE, 0x3F23D70A, 0x3F266666, > +0x3F28F5C3, 0x3F2B851F, 0x3F2E147B, 0x3F30A3D7, 0x3F333333, 0x3F35C28F, > +0x3F3851EC, 0x3F3AE148, 0x3F3D70A4, 0x3F400000, 0x3F428F5C, 0x3F451EB8, > +0x3F47AE14, 0x3F4A3D71, 0x3F4CCCCD, 0x3F4F5C29, 0x3F51EB85, 0x3F547AE1, > +0x3F570A3D, 0x3F59999A, 0x3F5C28F6, 0x3F5EB852, 0x3F6147AE, 0x3F63D70A, > +0x3F666666, 0x3F68F5C3, 0x3F6B851F, 0x3F6E147B, 0x3F70A3D7, 0x3F733333, > +0x3F75C28F, 0x3F7851EC, 0x3F7AE148, 0x3F7D70A4, 0x3F800000 Just nitpick: better to align with lower hex letters (a-f). > +}; > + > +static void podhd_set_monitor_level(struct usb_line6_podhd *podhd, int value) > +{ > + unsigned int fl; > + static const unsigned char msg[16] = { > + /* Chunk is 0xc bytes (without first word) */ > + 0x0c, 0x00, > + /* First chunk in the message */ > + 0x01, 0x00, > + /* Message size is 2 4-byte words */ > + 0x02, 0x00, > + /* Unknown */ > + 0x04, 0x41, > + /* Unknown */ > + 0x04, 0x00, 0x13, 0x00, > + /* Volume, LE float32, 0.0 - 1.0 */ > + 0x00, 0x00, 0x00, 0x00 > + }; > + unsigned char *buf; > + > + buf = kmalloc(sizeof(msg), GFP_ATOMIC); Is this function called from the irq context like the urb callback? I saw that it's called from the mixer put callback, and it's in the normal sleepable context, hence GFP_KERNEL can be used safely. thanks, Takashi