Hi,
On Mon, Sep 16, 2013 at 10:20:54PM +0200, Ondrej Zary wrote:
+static int snd_es938_read_reg(struct snd_es938 *chip, u8 reg, u8 *out) +{
- u8 buf[8];
- int i = 0, res;
- u8 sysex[] = { MIDI_CMD_COMMON_SYSEX, 0x00, 0x00, ES938_ID,
ES938_CMD_REG_R, reg, MIDI_CMD_COMMON_SYSEX_END };- unsigned long end_time;
- snd_rawmidi_kernel_write(chip->rfile.output, sysex, sizeof(sysex));
- memset(buf, 0, sizeof(buf));
- end_time = jiffies + msecs_to_jiffies(100);
- while (i < sizeof(buf)) {
res = snd_rawmidi_kernel_read(chip->rfile.input, buf + i,sizeof(buf) - i);if (res > 0)i += res;if (time_after(jiffies, end_time))return -1;- }
Forgive me, but I seem to faintly remember that it's preferred for user code to tend towards non-jiffies-based timing (IIRC due to NOHZ efforts etc.). So if that actually is the case, then one might want to change it to less jiffies-dependent handling (use non-jiffies helpers), but then how?
+static void snd_es938_write_reg(struct snd_es938 *chip, u8 reg, u8 val) +{
- u8 sysex[] = { MIDI_CMD_COMMON_SYSEX, 0x00, 0x00, ES938_ID,
ES938_CMD_REG_W, reg, val, MIDI_CMD_COMMON_SYSEX_END };- snd_rawmidi_kernel_write(chip->rfile.output, sysex, sizeof(sysex));
snd_rawmidi_kernel_write() is prototyped as const unsigned char *buf, so perhaps... const unsigned char buf[] = ...;? (static const probably not so useful e.g. since static const may be rather prone to cache misses)
Though personally I do favour u8, since "char" seems so unsuitably stringy - but the prototype currently doesn't offer it typed that way...
(Almost-)Reviewed-By: Andreas Mohr andim2@users.sf.net
Andreas Mohr