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[PATCH 2/4] ASoC: ti: davinci-mcasp: Disambiguate mcasp_is_synchronous function

Sen Wang posted 4 patches 1 week, 2 days ago
There is a newer version of this series
[PATCH 2/4] ASoC: ti: davinci-mcasp: Disambiguate mcasp_is_synchronous function
Posted by Sen Wang 1 week, 2 days ago 
The current mcasp_is_synchronous() function does more than what it
proclaims, it also checks if McASP is a frame producer.

Therefore split the original function into two separate ones and
replace all occurrences with the new equivalent logic. So the functions
can be re-used when checking async/sync status in light of async mode
enhancements.

Signed-off-by: Sen Wang <sen@ti.com>
---
 sound/soc/ti/davinci-mcasp.c | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/sound/soc/ti/davinci-mcasp.c b/sound/soc/ti/davinci-mcasp.c
index 621a9d5f9377..aa14fc1c8011 100644
--- a/sound/soc/ti/davinci-mcasp.c
+++ b/sound/soc/ti/davinci-mcasp.c
@@ -179,10 +179,16 @@ static void mcasp_set_ctl_reg(struct davinci_mcasp *mcasp, u32 ctl_reg, u32 val)
 
 static bool mcasp_is_synchronous(struct davinci_mcasp *mcasp)
 {
-	u32 rxfmctl = mcasp_get_reg(mcasp, DAVINCI_MCASP_RXFMCTL_REG);
 	u32 aclkxctl = mcasp_get_reg(mcasp, DAVINCI_MCASP_ACLKXCTL_REG);
 
-	return !(aclkxctl & TX_ASYNC) && rxfmctl & AFSRE;
+	return !(aclkxctl & TX_ASYNC);
+}
+
+static bool mcasp_is_frame_producer(struct davinci_mcasp *mcasp)
+{
+	u32 rxfmctl = mcasp_get_reg(mcasp, DAVINCI_MCASP_RXFMCTL_REG);
+
+	return rxfmctl & AFSRE;
 }
 
 static inline void mcasp_set_clk_pdir(struct davinci_mcasp *mcasp, bool enable)
@@ -226,7 +232,7 @@ static void mcasp_start_rx(struct davinci_mcasp *mcasp)
 	 * synchronously from the transmit clock and frame sync. We need to make
 	 * sure that the TX signlas are enabled when starting reception.
 	 */
-	if (mcasp_is_synchronous(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);
@@ -239,7 +245,7 @@ static void mcasp_start_rx(struct davinci_mcasp *mcasp)
 	mcasp_set_ctl_reg(mcasp, DAVINCI_MCASP_GBLCTLR_REG, RXSMRST);
 	/* Release Frame Sync generator */
 	mcasp_set_ctl_reg(mcasp, DAVINCI_MCASP_GBLCTLR_REG, RXFSRST);
-	if (mcasp_is_synchronous(mcasp))
+	if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp))
 		mcasp_set_ctl_reg(mcasp, DAVINCI_MCASP_GBLCTLX_REG, TXFSRST);
 
 	/* enable receive IRQs */
@@ -305,7 +311,7 @@ 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_synchronous(mcasp) && !mcasp->streams) {
+	if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp) && !mcasp->streams) {
 		mcasp_set_clk_pdir(mcasp, false);
 		mcasp_set_reg(mcasp, DAVINCI_MCASP_GBLCTLX_REG, 0);
 	}
@@ -332,7 +338,7 @@ static void mcasp_stop_tx(struct davinci_mcasp *mcasp)
 	 * In synchronous mode keep TX clocks running if the capture stream is
 	 * still running.
 	 */
-	if (mcasp_is_synchronous(mcasp) && mcasp->streams)
+	if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp) && mcasp->streams)
 		val =  TXHCLKRST | TXCLKRST | TXFSRST;
 	else
 		mcasp_set_clk_pdir(mcasp, false);
@@ -1041,7 +1047,8 @@ static int mcasp_i2s_hw_param(struct davinci_mcasp *mcasp, int stream,
 		 * not running already we need to configure the TX slots in
 		 * order to have correct FSX on the bus
 		 */
-		if (mcasp_is_synchronous(mcasp) && !mcasp->channels)
+		if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp) &&
+		    !mcasp->channels)
 			mcasp_mod_bits(mcasp, DAVINCI_MCASP_TXFMCTL_REG,
 				       FSXMOD(total_slots), FSXMOD(0x1FF));
 	}
-- 
2.43.0
Re: [PATCH 2/4] ASoC: ti: davinci-mcasp: Disambiguate mcasp_is_synchronous function
Posted by Péter Ujfalusi 6 days, 11 hours ago 

On 30/01/2026 07:10, Sen Wang wrote:
> The current mcasp_is_synchronous() function does more than what it
> proclaims, it also checks if McASP is a frame producer.

True, the naming was not too precise. It is tasked to decide if the TX
clock needs to be enabled for RX operation, which precisely when McASP
is in synchronous mode _and_ it is clock provider.

> Therefore split the original function into two separate ones and
> replace all occurrences with the new equivalent logic. So the functions
> can be re-used when checking async/sync status in light of async mode
> enhancements.

Acked-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>

>
> Signed-off-by: Sen Wang <sen@ti.com>
> ---
>  sound/soc/ti/davinci-mcasp.c | 21 ++++++++++++++-------
>  1 file changed, 14 insertions(+), 7 deletions(-)
>
> diff --git a/sound/soc/ti/davinci-mcasp.c b/sound/soc/ti/davinci-mcasp.c
> index 621a9d5f9377..aa14fc1c8011 100644
> --- a/sound/soc/ti/davinci-mcasp.c
> +++ b/sound/soc/ti/davinci-mcasp.c
> @@ -179,10 +179,16 @@ static void mcasp_set_ctl_reg(struct
davinci_mcasp *mcasp, u32 ctl_reg, u32 val)
>
>  static bool mcasp_is_synchronous(struct davinci_mcasp *mcasp)
>  {
> -	u32 rxfmctl = mcasp_get_reg(mcasp, DAVINCI_MCASP_RXFMCTL_REG);
>  	u32 aclkxctl = mcasp_get_reg(mcasp, DAVINCI_MCASP_ACLKXCTL_REG);
>
> -	return !(aclkxctl & TX_ASYNC) && rxfmctl & AFSRE;
> +	return !(aclkxctl & TX_ASYNC);
> +}
> +
> +static bool mcasp_is_frame_producer(struct davinci_mcasp *mcasp)
> +{
> +	u32 rxfmctl = mcasp_get_reg(mcasp, DAVINCI_MCASP_RXFMCTL_REG);
> +
> +	return rxfmctl & AFSRE;
>  }
>
>  static inline void mcasp_set_clk_pdir(struct davinci_mcasp *mcasp,
bool enable)
> @@ -226,7 +232,7 @@ static void mcasp_start_rx(struct davinci_mcasp
*mcasp)
>  	 * synchronously from the transmit clock and frame sync. We need to make
>  	 * sure that the TX signlas are enabled when starting reception.
>  	 */
> -	if (mcasp_is_synchronous(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);
> @@ -239,7 +245,7 @@ static void mcasp_start_rx(struct davinci_mcasp
*mcasp)
>  	mcasp_set_ctl_reg(mcasp, DAVINCI_MCASP_GBLCTLR_REG, RXSMRST);
>  	/* Release Frame Sync generator */
>  	mcasp_set_ctl_reg(mcasp, DAVINCI_MCASP_GBLCTLR_REG, RXFSRST);
> -	if (mcasp_is_synchronous(mcasp))
> +	if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp))
>  		mcasp_set_ctl_reg(mcasp, DAVINCI_MCASP_GBLCTLX_REG, TXFSRST);
>
>  	/* enable receive IRQs */
> @@ -305,7 +311,7 @@ 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_synchronous(mcasp) && !mcasp->streams) {
> +	if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp) &&
!mcasp->streams) {
>  		mcasp_set_clk_pdir(mcasp, false);
>  		mcasp_set_reg(mcasp, DAVINCI_MCASP_GBLCTLX_REG, 0);
>  	}
> @@ -332,7 +338,7 @@ static void mcasp_stop_tx(struct davinci_mcasp *mcasp)
>  	 * In synchronous mode keep TX clocks running if the capture stream is
>  	 * still running.
>  	 */
> -	if (mcasp_is_synchronous(mcasp) && mcasp->streams)
> +	if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp) &&
mcasp->streams)
>  		val =  TXHCLKRST | TXCLKRST | TXFSRST;
>  	else
>  		mcasp_set_clk_pdir(mcasp, false);
> @@ -1041,7 +1047,8 @@ static int mcasp_i2s_hw_param(struct
davinci_mcasp *mcasp, int stream,
>  		 * not running already we need to configure the TX slots in
>  		 * order to have correct FSX on the bus
>  		 */
> -		if (mcasp_is_synchronous(mcasp) && !mcasp->channels)
> +		if (mcasp_is_frame_producer(mcasp) && mcasp_is_synchronous(mcasp) &&
> +		    !mcasp->channels)
>  			mcasp_mod_bits(mcasp, DAVINCI_MCASP_TXFMCTL_REG,
>  				       FSXMOD(total_slots), FSXMOD(0x1FF));
>  	}
-- 
Péter

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