Add support for 44.1Khz frequency by dynamically calculating the slimbus parameters instead of statically defining them.
Co-developed-by: Prudhvi Yarlagadda pyarlaga@codeaurora.org Signed-off-by: Prudhvi Yarlagadda pyarlaga@codeaurora.org Signed-off-by: Krzysztof Kozlowski krzysztof.kozlowski@linaro.org --- drivers/slimbus/qcom-ngd-ctrl.c | 64 ++++++++++++++++++++++++++++++--- 1 file changed, 59 insertions(+), 5 deletions(-)
diff --git a/drivers/slimbus/qcom-ngd-ctrl.c b/drivers/slimbus/qcom-ngd-ctrl.c index ac84fdc2822f..051ac5cba207 100644 --- a/drivers/slimbus/qcom-ngd-ctrl.c +++ b/drivers/slimbus/qcom-ngd-ctrl.c @@ -944,6 +944,54 @@ static int qcom_slim_ngd_xfer_msg_sync(struct slim_controller *ctrl, return ret; }
+static int qcom_slim_calc_coef(struct slim_stream_runtime *rt, int *exp) +{ + struct slim_controller *ctrl = rt->dev->ctrl; + int coef; + + if (rt->ratem * ctrl->a_framer->superfreq < rt->rate) + rt->ratem++; + + coef = rt->ratem; + *exp = 0; + + /* + * CRM = Cx(2^E) is the formula we are using. + * Here C is the coffecient and E is the exponent. + * CRM is the Channel Rate Multiplier. + * Coefficeint should be either 1 or 3 and exponenet + * should be an integer between 0 to 9, inclusive. + */ + while (1) { + while ((coef & 0x1) != 0x1) { + coef >>= 1; + *exp = *exp + 1; + } + + if (coef <= 3) + break; + + coef++; + } + + /* + * we rely on the coef value (1 or 3) to set a bit + * in the slimbus message packet. This bit is + * BIT(5) which is the segment rate coefficient. + */ + if (coef == 1) { + if (*exp > 9) + return -EIO; + coef = 0; + } else { + if (*exp > 8) + return -EIO; + coef = 1; + } + + return coef; +} + static int qcom_slim_ngd_enable_stream(struct slim_stream_runtime *rt) { struct slim_device *sdev = rt->dev; @@ -967,16 +1015,22 @@ static int qcom_slim_ngd_enable_stream(struct slim_stream_runtime *rt) struct slim_port *port = &rt->ports[i];
if (txn.msg->num_bytes == 0) { - int seg_interval = SLIM_SLOTS_PER_SUPERFRAME/rt->ratem; - int exp; + int exp = 0, coef = 0;
wbuf[txn.msg->num_bytes++] = sdev->laddr; wbuf[txn.msg->num_bytes] = rt->bps >> 2 | (port->ch.aux_fmt << 6);
- /* Data channel segment interval not multiple of 3 */ - exp = seg_interval % 3; - if (exp) + /* calculate coef dynamically */ + coef = qcom_slim_calc_coef(rt, &exp); + if (coef < 0) { + dev_err(&sdev->dev, + "%s: error calculating coef %d\n", __func__, + coef); + return -EIO; + } + + if (coef) wbuf[txn.msg->num_bytes] |= BIT(5);
txn.msg->num_bytes++;