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[PATCH 3/4] ASoC: ti: davinci-mcasp: Streamline pdir behavior across rx & tx streams

Sen Wang posted 4 patches 1 week, 2 days ago
There is a newer version of this series
[PATCH 3/4] ASoC: ti: davinci-mcasp: Streamline pdir behavior across rx & tx streams
Posted by Sen Wang 1 week, 2 days ago 
Simplify the mcasp_set_clk_pdir caller convention in start/stop stream
function, to make it so that set_clk_pdir gets called regardless when
stream starts and also disables when stream ends.

Functionality-wise, everything remains the same as the previously skipped
calls are now either correctly configured
(when McASP is SND_SOC_DAIFMT_BP_FC - pdir needs to be enabled)
or called with a bitmask of zero (when McASP is SND_SOC_DAIFMT_BC_FC - pdir
gets disabled).

On brief regarding McASP Clock and Frame sync configurations, refer to [0].

[0]:TRM Section 12.1.1.4.2 https://www.ti.com/lit/ug/sprujd4a/sprujd4a.pdf

Signed-off-by: Sen Wang <sen@ti.com>
---
 sound/soc/ti/davinci-mcasp.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/sound/soc/ti/davinci-mcasp.c b/sound/soc/ti/davinci-mcasp.c
index aa14fc1c8011..4f8a2ce6ce78 100644
--- a/sound/soc/ti/davinci-mcasp.c
+++ b/sound/soc/ti/davinci-mcasp.c
@@ -235,8 +235,8 @@ static void mcasp_start_rx(struct davinci_mcasp *mcasp)
 	if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp)) {
 		mcasp_set_ctl_reg(mcasp, DAVINCI_MCASP_GBLCTLX_REG, TXHCLKRST);
 		mcasp_set_ctl_reg(mcasp, DAVINCI_MCASP_GBLCTLX_REG, TXCLKRST);
-		mcasp_set_clk_pdir(mcasp, true);
 	}
+	mcasp_set_clk_pdir(mcasp, true);
 
 	/* Activate serializer(s) */
 	mcasp_set_reg(mcasp, DAVINCI_MCASP_RXSTAT_REG, 0xFFFFFFFF);
@@ -311,10 +311,10 @@ static void mcasp_stop_rx(struct davinci_mcasp *mcasp)
 	 * In synchronous mode stop the TX clocks if no other stream is
 	 * running
 	 */
-	if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp) && !mcasp->streams) {
-		mcasp_set_clk_pdir(mcasp, false);
+	if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp) && !mcasp->streams)
 		mcasp_set_reg(mcasp, DAVINCI_MCASP_GBLCTLX_REG, 0);
-	}
+	if (!mcasp->streams)
+		mcasp_set_clk_pdir(mcasp, false);
 
 	mcasp_set_reg(mcasp, DAVINCI_MCASP_GBLCTLR_REG, 0);
 	mcasp_set_reg(mcasp, DAVINCI_MCASP_RXSTAT_REG, 0xFFFFFFFF);
@@ -340,7 +340,7 @@ static void mcasp_stop_tx(struct davinci_mcasp *mcasp)
 	 */
 	if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp) && mcasp->streams)
 		val =  TXHCLKRST | TXCLKRST | TXFSRST;
-	else
+	if (!mcasp->streams)
 		mcasp_set_clk_pdir(mcasp, false);
 
 
-- 
2.43.0
Re: [PATCH 3/4] ASoC: ti: davinci-mcasp: Streamline pdir behavior across rx & tx streams
Posted by Péter Ujfalusi 6 days, 7 hours ago 

On 30/01/2026 07:10, Sen Wang wrote:
> Simplify the mcasp_set_clk_pdir caller convention in start/stop stream
> function, to make it so that set_clk_pdir gets called regardless when
> stream starts and also disables when stream ends.
> 
> Functionality-wise, everything remains the same as the previously skipped
> calls are now either correctly configured
> (when McASP is SND_SOC_DAIFMT_BP_FC - pdir needs to be enabled)
> or called with a bitmask of zero (when McASP is SND_SOC_DAIFMT_BC_FC - pdir
> gets disabled).
> 
> On brief regarding McASP Clock and Frame sync configurations, refer to [0].
> 
> [0]:TRM Section 12.1.1.4.2 https://www.ti.com/lit/ug/sprujd4a/sprujd4a.pdf
> 
> Signed-off-by: Sen Wang <sen@ti.com>
> ---
>  sound/soc/ti/davinci-mcasp.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/sound/soc/ti/davinci-mcasp.c b/sound/soc/ti/davinci-mcasp.c
> index aa14fc1c8011..4f8a2ce6ce78 100644
> --- a/sound/soc/ti/davinci-mcasp.c
> +++ b/sound/soc/ti/davinci-mcasp.c
> @@ -235,8 +235,8 @@ static void mcasp_start_rx(struct davinci_mcasp *mcasp)
>  	if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp)) {
>  		mcasp_set_ctl_reg(mcasp, DAVINCI_MCASP_GBLCTLX_REG, TXHCLKRST);
>  		mcasp_set_ctl_reg(mcasp, DAVINCI_MCASP_GBLCTLX_REG, TXCLKRST);
> -		mcasp_set_clk_pdir(mcasp, true);
>  	}
> +	mcasp_set_clk_pdir(mcasp, true);
>  
>  	/* Activate serializer(s) */
>  	mcasp_set_reg(mcasp, DAVINCI_MCASP_RXSTAT_REG, 0xFFFFFFFF);
> @@ -311,10 +311,10 @@ static void mcasp_stop_rx(struct davinci_mcasp *mcasp)
>  	 * In synchronous mode stop the TX clocks if no other stream is
>  	 * running
>  	 */
> -	if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp) && !mcasp->streams) {
> -		mcasp_set_clk_pdir(mcasp, false);
> +	if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp) && !mcasp->streams)
>  		mcasp_set_reg(mcasp, DAVINCI_MCASP_GBLCTLX_REG, 0);
> -	}
> +	if (!mcasp->streams)
> +		mcasp_set_clk_pdir(mcasp, false);

I'm not sure about this, but the sequence should be preserved, PDIR
change first.

>  
>  	mcasp_set_reg(mcasp, DAVINCI_MCASP_GBLCTLR_REG, 0);
>  	mcasp_set_reg(mcasp, DAVINCI_MCASP_RXSTAT_REG, 0xFFFFFFFF);
> @@ -340,7 +340,7 @@ static void mcasp_stop_tx(struct davinci_mcasp *mcasp)
>  	 */
>  	if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp) && mcasp->streams)
>  		val =  TXHCLKRST | TXCLKRST | TXFSRST;
> -	else
> +	if (!mcasp->streams)
>  		mcasp_set_clk_pdir(mcasp, false);
>  
>  

-- 
Péter
Re: [PATCH 3/4] ASoC: ti: davinci-mcasp: Streamline pdir behavior across rx & tx streams
Posted by Sen Wang 6 days, 3 hours ago 
On 2/2/26 10:49, Péter Ujfalusi wrote:
> 
> 
> On 30/01/2026 07:10, Sen Wang wrote:
>> Simplify the mcasp_set_clk_pdir caller convention in start/stop stream
>> function, to make it so that set_clk_pdir gets called regardless when
>> stream starts and also disables when stream ends.
>>
>> Functionality-wise, everything remains the same as the previously skipped
>> calls are now either correctly configured
>> (when McASP is SND_SOC_DAIFMT_BP_FC - pdir needs to be enabled)
>> or called with a bitmask of zero (when McASP is SND_SOC_DAIFMT_BC_FC - pdir
>> gets disabled).
>>
>> On brief regarding McASP Clock and Frame sync configurations, refer to [0].
>>
>> [0]:TRM Section 12.1.1.4.2 https://www.ti.com/lit/ug/sprujd4a/sprujd4a.pdf
>>
>> Signed-off-by: Sen Wang <sen@ti.com>
>> ---
>>   sound/soc/ti/davinci-mcasp.c | 10 +++++-----
>>   1 file changed, 5 insertions(+), 5 deletions(-)
>>
>> diff --git a/sound/soc/ti/davinci-mcasp.c b/sound/soc/ti/davinci-mcasp.c
>> index aa14fc1c8011..4f8a2ce6ce78 100644
>> --- a/sound/soc/ti/davinci-mcasp.c
>> +++ b/sound/soc/ti/davinci-mcasp.c
>> @@ -235,8 +235,8 @@ static void mcasp_start_rx(struct davinci_mcasp *mcasp)
>>   	if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp)) {
>>   		mcasp_set_ctl_reg(mcasp, DAVINCI_MCASP_GBLCTLX_REG, TXHCLKRST);
>>   		mcasp_set_ctl_reg(mcasp, DAVINCI_MCASP_GBLCTLX_REG, TXCLKRST);
>> -		mcasp_set_clk_pdir(mcasp, true);
>>   	}
>> +	mcasp_set_clk_pdir(mcasp, true);
>>   
>>   	/* Activate serializer(s) */
>>   	mcasp_set_reg(mcasp, DAVINCI_MCASP_RXSTAT_REG, 0xFFFFFFFF);
>> @@ -311,10 +311,10 @@ static void mcasp_stop_rx(struct davinci_mcasp *mcasp)
>>   	 * In synchronous mode stop the TX clocks if no other stream is
>>   	 * running
>>   	 */
>> -	if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp) && !mcasp->streams) {
>> -		mcasp_set_clk_pdir(mcasp, false);
>> +	if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp) && !mcasp->streams)
>>   		mcasp_set_reg(mcasp, DAVINCI_MCASP_GBLCTLX_REG, 0);
>> -	}
>> +	if (!mcasp->streams)
>> +		mcasp_set_clk_pdir(mcasp, false);
> 
> I'm not sure about this, but the sequence should be preserved, PDIR
> change first.
> 

Sounds good, I'll enforce the original order of operation in the new patch.

>>   
>>   	mcasp_set_reg(mcasp, DAVINCI_MCASP_GBLCTLR_REG, 0);
>>   	mcasp_set_reg(mcasp, DAVINCI_MCASP_RXSTAT_REG, 0xFFFFFFFF);
>> @@ -340,7 +340,7 @@ static void mcasp_stop_tx(struct davinci_mcasp *mcasp)
>>   	 */
>>   	if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp) && mcasp->streams)
>>   		val =  TXHCLKRST | TXCLKRST | TXFSRST;
>> -	else
>> +	if (!mcasp->streams)
>>   		mcasp_set_clk_pdir(mcasp, false);
>>   
>>   
> 

Best,
Sen Wang

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