On 8/23/2022 10:52 AM, Pierre-Louis Bossart wrote:
Hi Amadeusz,
+int intel_nhlt_ssp_mclk_mask(struct nhlt_acpi_table *nhlt, int ssp_num)
+{
+ struct nhlt_endpoint *epnt;
+ struct nhlt_fmt *fmt;
+ struct nhlt_fmt_cfg *cfg;
+ int mclk_mask = 0;
+ int i, j;
+
+ if (!nhlt)
+ return 0;
+
+ epnt = (struct nhlt_endpoint *)nhlt->desc;
+ for (i = 0; i < nhlt->endpoint_count; i++) {
+
+ /* we only care about endpoints connected to an audio codec
over SSP */
+ if (epnt->linktype == NHLT_LINK_SSP &&
+ epnt->device_type == NHLT_DEVICE_I2S &&
+ epnt->virtual_bus_id == ssp_num) {
if (epnt->linktype != NHLT_LINK_SSP ||
epnt->device_type != NHLT_DEVICE_I2S ||
epnt->virtual_bus_id != ssp_num)
continue;
and then you can remove one indentation level below?
Would that work? We still need to move the epnt pointer:
epnt = (struct nhlt_endpoint *)((u8 *)epnt + epnt->length);
and moving this in the endpoint_count loop would be ugly as well.
Another solution would be goto to skip, but that also seems ugly :/
I guess it can stay as it is then.
+
+ fmt = (struct nhlt_fmt *)(epnt->config.caps +
epnt->config.size);
+ cfg = fmt->fmt_config;
+
+ /*
+ * In theory all formats should use the same MCLK but it
doesn't hurt to
+ * double-check that the configuration is consistent
+ */
+ for (j = 0; j < fmt->fmt_count; j++) {
+ u32 *blob;
+ int mdivc_offset;
+
+ if (cfg->config.size >= SSP_BLOB_V1_0_SIZE) {
+ blob = (u32 *)cfg->config.caps;
+
+ if (blob[1] == SSP_BLOB_VER_2_0)
+ mdivc_offset = SSP_BLOB_V2_0_MDIVC_OFFSET;
+ else if (blob[1] == SSP_BLOB_VER_1_5)
+ mdivc_offset = SSP_BLOB_V1_5_MDIVC_OFFSET;
+ else
+ mdivc_offset = SSP_BLOB_V1_0_MDIVC_OFFSET;
+
+ mclk_mask |= blob[mdivc_offset] & GENMASK(1, 0);
One more thing, where does this GENMASK come from, as far as I can tell
HW specifies and FW uses one bit field to signal that MCLK is enabled?
(mdivc is simply a value written to HW register to configure it).
+ }
+
+ cfg = (struct nhlt_fmt_cfg *)(cfg->config.caps +
cfg->config.size);
+ }
+ }
+ epnt = (struct nhlt_endpoint *)((u8 *)epnt + epnt->length);
+ }
+
+ return mclk_mask;
Although I understand that it is relegated to the caller, but if both
mclk being set is considered an error maybe add some kind of check here
instead and free callers from having to remember about it?
if (hweight_long(mclk_mask) != 1)
return -EINVAL;
return mclk_mask;
I went back and forth multiple times on this one. I can't figure out if
this would be a bug or a feature, it could be e.g. a test capability and
it's supported in hardware. I decided to make the decision in the caller
rather than a lower level in the library.
If the tools used to generate NHLT don't support this multi-MCLK mode
then we could indeed move the test here.
Considering comment I added above I've asked Czarek to also check this
series. I'm not sure it even makes sense to name the field "_mask" when
it is one bit...
+}
+EXPORT_SYMBOL(intel_nhlt_ssp_mclk_mask);
+
static struct nhlt_specific_cfg *
nhlt_get_specific_cfg(struct device *dev, struct nhlt_fmt *fmt, u8
num_ch,
u32 rate, u8 vbps, u8 bps)
