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slimbus: qcom-ngd-ctrl: add support for 44.1 Khz frequency

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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>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20221118065246.6835-5-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Krzysztof Kozlowski 2022-11-18 06:52:38 +00:00 committed by Greg Kroah-Hartman
parent 434d257281
commit 4594cb4b76
1 changed files with 59 additions and 5 deletions
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64
drivers/slimbus/qcom-ngd-ctrl.c
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@ -944,6 +944,54 @@ pm_put:
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++;