[PATCH] staging: dgnc: replace dgnc_offset_table with bit shift.

[PATCH] staging: dgnc: replace dgnc_offset_table with bit shift.

[Daeseok Youn]

the dgnc_offset_table has a same value with (1 << port).
So I tried to replace dgnc_offset_table array with 1 << port.
And also there are redundant assignments(tmp and current_port)
inside while loop for checking uart port, and remove them.

Signed-off-by: Daeseok Youn <daeseok.youn@gmail.com>
---
Greg, This patch depends on previous patches.
here are links(previous):
1. https://lkml.org/lkml/2016/3/24/661
2. https://lkml.org/lkml/2016/3/24/663

if those patches are failed to merge, I will send them again after
fixing them.

thanks.

 drivers/staging/dgnc/dgnc_neo.c | 44 +++++++++++++++++++----------------------
 1 file changed, 20 insertions(+), 24 deletions(-)

diff --git a/drivers/staging/dgnc/dgnc_neo.c b/drivers/staging/dgnc/dgnc_neo.c
index d732e6e..8b6bc73 100644
--- a/drivers/staging/dgnc/dgnc_neo.c
+++ b/drivers/staging/dgnc/dgnc_neo.c
@@ -77,9 +77,6 @@ struct board_ops dgnc_neo_ops = {
 	.send_immediate_char =		neo_send_immediate_char
 };
 
-static uint dgnc_offset_table[8] = { 0x01, 0x02, 0x04, 0x08,
-				     0x10, 0x20, 0x40, 0x80 };
-
 /*
  * This function allows calls to ensure that all outstanding
  * PCI writes have been completed, by doing a PCI read against
@@ -923,9 +920,7 @@ static irqreturn_t neo_intr(int irq, void *voidbrd)
 	struct dgnc_board *brd = voidbrd;
 	struct channel_t *ch;
 	int port = 0;
-	int type = 0;
-	int current_port;
-	u32 tmp;
+	int type;
 	u32 uart_poll;
 	unsigned long flags;
 	unsigned long flags2;
@@ -960,28 +955,29 @@ static irqreturn_t neo_intr(int irq, void *voidbrd)
 
 	/* At this point, we have at least SOMETHING to service, dig further... */
 
-	current_port = 0;
-
 	/* Loop on each port */
 	while ((uart_poll & 0xff) != 0) {
-		tmp = uart_poll;
-
-		/* Check current port to see if it has interrupt pending */
-		if ((tmp & dgnc_offset_table[current_port]) != 0) {
-			port = current_port;
-			type = tmp >> (8 + (port * 3));
-			type &= 0x7;
-		} else {
-			current_port++;
-			continue;
-		}
+		int i;
 
-		/* Remove this port + type from uart_poll */
-		uart_poll &= ~(dgnc_offset_table[port]);
+		type = 0;
 
-		if (!type) {
-			/* If no type, just ignore it, and move onto next port */
-			continue;
+		for (i = port; i < MAXPORTS; i++) {
+			unsigned int offset_table = 0x1 << i;
+
+			/* Check current port to see
+			 * if it has interrupt pending
+			 */
+			if ((uart_poll & offset_table) != 0) {
+				port = i;
+				type = uart_poll >> (8 + (port * 3));
+				type &= 0x7;
+
+				/* Remove this port + type from uart_poll */
+				uart_poll &= ~(offset_table);
+			}
+
+			if (type)
+				break;
 		}
 
 		/* Switch on type of interrupt we have */
-- 
1.9.1

Re: [PATCH] staging: dgnc: replace dgnc_offset_table with bit shift.

[walter harms]

Am 25.03.2016 12:33, schrieb Daeseok Youn:
> the dgnc_offset_table has a same value with (1 << port).
> So I tried to replace dgnc_offset_table array with 1 << port.
> And also there are redundant assignments(tmp and current_port)
> inside while loop for checking uart port, and remove them.
> 
> Signed-off-by: Daeseok Youn <daeseok.youn@gmail.com>
> ---
> Greg, This patch depends on previous patches.
> here are links(previous):
> 1. https://lkml.org/lkml/2016/3/24/661
> 2. https://lkml.org/lkml/2016/3/24/663
> 
> if those patches are failed to merge, I will send them again after
> fixing them.
> 
> thanks.
> 
>  drivers/staging/dgnc/dgnc_neo.c | 44 +++++++++++++++++++----------------------
>  1 file changed, 20 insertions(+), 24 deletions(-)
> 
> diff --git a/drivers/staging/dgnc/dgnc_neo.c b/drivers/staging/dgnc/dgnc_neo.c
> index d732e6e..8b6bc73 100644
> --- a/drivers/staging/dgnc/dgnc_neo.c
> +++ b/drivers/staging/dgnc/dgnc_neo.c
> @@ -77,9 +77,6 @@ struct board_ops dgnc_neo_ops = {
>  	.send_immediate_char =		neo_send_immediate_char
>  };
>  
> -static uint dgnc_offset_table[8] = { 0x01, 0x02, 0x04, 0x08,
> -				     0x10, 0x20, 0x40, 0x80 };
> -
>  /*
>   * This function allows calls to ensure that all outstanding
>   * PCI writes have been completed, by doing a PCI read against
> @@ -923,9 +920,7 @@ static irqreturn_t neo_intr(int irq, void *voidbrd)
>  	struct dgnc_board *brd = voidbrd;
>  	struct channel_t *ch;
>  	int port = 0;
> -	int type = 0;
> -	int current_port;
> -	u32 tmp;
> +	int type;
>  	u32 uart_poll;
>  	unsigned long flags;
>  	unsigned long flags2;
> @@ -960,28 +955,29 @@ static irqreturn_t neo_intr(int irq, void *voidbrd)
>  
>  	/* At this point, we have at least SOMETHING to service, dig further... */
>  
> -	current_port = 0;
> -
>  	/* Loop on each port */
>  	while ((uart_poll & 0xff) != 0) {
> -		tmp = uart_poll;
> -
> -		/* Check current port to see if it has interrupt pending */
> -		if ((tmp & dgnc_offset_table[current_port]) != 0) {
> -			port = current_port;
> -			type = tmp >> (8 + (port * 3));
> -			type &= 0x7;
> -		} else {
> -			current_port++;
> -			continue;
> -		}
> +		int i;
>  
> -		/* Remove this port + type from uart_poll */
> -		uart_poll &= ~(dgnc_offset_table[port]);
> +		type = 0;
>  
> -		if (!type) {
> -			/* If no type, just ignore it, and move onto next port */
> -			continue;
> +		for (i = port; i < MAXPORTS; i++) {
> +			unsigned int offset_table = 0x1 << i;
> +
> +			/* Check current port to see
> +			 * if it has interrupt pending
> +			 */
> +			if ((uart_poll & offset_table) != 0) {
> +				port = i;
> +				type = uart_poll >> (8 + (port * 3));
> +				type &= 0x7;
> +
> +				/* Remove this port + type from uart_poll */
> +				uart_poll &= ~(offset_table);

	why not: art_poll &= ~ (0x1 << i);
	then you can easy eliminate offset_table	

	btw: why do you need i ?

	re,
	 wh

> +			}
> +
> +			if (type)
> +				break;
>  		}
>  
>  		/* Switch on type of interrupt we have */

Re: [PATCH] staging: dgnc: replace dgnc_offset_table with bit shift.

[DaeSeok Youn]

2016-03-25 22:15 GMT+09:00 walter harms <wharms@bfs.de>:
>
>
> Am 25.03.2016 12:33, schrieb Daeseok Youn:
>> the dgnc_offset_table has a same value with (1 << port).
>> So I tried to replace dgnc_offset_table array with 1 << port.
>> And also there are redundant assignments(tmp and current_port)
>> inside while loop for checking uart port, and remove them.
>>
>> Signed-off-by: Daeseok Youn <daeseok.youn@gmail.com>
>> ---
>> Greg, This patch depends on previous patches.
>> here are links(previous):
>> 1. https://lkml.org/lkml/2016/3/24/661
>> 2. https://lkml.org/lkml/2016/3/24/663
>>
>> if those patches are failed to merge, I will send them again after
>> fixing them.
>>
>> thanks.
>>
>>  drivers/staging/dgnc/dgnc_neo.c | 44 +++++++++++++++++++----------------------
>>  1 file changed, 20 insertions(+), 24 deletions(-)
>>
>> diff --git a/drivers/staging/dgnc/dgnc_neo.c b/drivers/staging/dgnc/dgnc_neo.c
>> index d732e6e..8b6bc73 100644
>> --- a/drivers/staging/dgnc/dgnc_neo.c
>> +++ b/drivers/staging/dgnc/dgnc_neo.c
>> @@ -77,9 +77,6 @@ struct board_ops dgnc_neo_ops = {
>>       .send_immediate_char =          neo_send_immediate_char
>>  };
>>
>> -static uint dgnc_offset_table[8] = { 0x01, 0x02, 0x04, 0x08,
>> -                                  0x10, 0x20, 0x40, 0x80 };
>> -
>>  /*
>>   * This function allows calls to ensure that all outstanding
>>   * PCI writes have been completed, by doing a PCI read against
>> @@ -923,9 +920,7 @@ static irqreturn_t neo_intr(int irq, void *voidbrd)
>>       struct dgnc_board *brd = voidbrd;
>>       struct channel_t *ch;
>>       int port = 0;
>> -     int type = 0;
>> -     int current_port;
>> -     u32 tmp;
>> +     int type;
>>       u32 uart_poll;
>>       unsigned long flags;
>>       unsigned long flags2;
>> @@ -960,28 +955,29 @@ static irqreturn_t neo_intr(int irq, void *voidbrd)
>>
>>       /* At this point, we have at least SOMETHING to service, dig further... */
>>
>> -     current_port = 0;
>> -
>>       /* Loop on each port */
>>       while ((uart_poll & 0xff) != 0) {
>> -             tmp = uart_poll;
>> -
>> -             /* Check current port to see if it has interrupt pending */
>> -             if ((tmp & dgnc_offset_table[current_port]) != 0) {
>> -                     port = current_port;
>> -                     type = tmp >> (8 + (port * 3));
>> -                     type &= 0x7;
>> -             } else {
>> -                     current_port++;
>> -                     continue;
>> -             }
>> +             int i;
>>
>> -             /* Remove this port + type from uart_poll */
>> -             uart_poll &= ~(dgnc_offset_table[port]);
>> +             type = 0;
>>
>> -             if (!type) {
>> -                     /* If no type, just ignore it, and move onto next port */
>> -                     continue;
>> +             for (i = port; i < MAXPORTS; i++) {
>> +                     unsigned int offset_table = 0x1 << i;
>> +
>> +                     /* Check current port to see
>> +                      * if it has interrupt pending
>> +                      */
>> +                     if ((uart_poll & offset_table) != 0) {
>> +                             port = i;
>> +                             type = uart_poll >> (8 + (port * 3));
>> +                             type &= 0x7;
>> +
>> +                             /* Remove this port + type from uart_poll */
>> +                             uart_poll &= ~(offset_table);
>
>         why not: art_poll &= ~ (0x1 << i);
>         then you can easy eliminate offset_table
>
>         btw: why do you need i ?
>
>         re,
>          wh

Hi, walter.

I'm sorry for reply lately. :-)
Ok. I will try clean up useless variables and send this again.

Thanks.

regards,
Daeseok.
>
>> +                     }
>> +
>> +                     if (type)
>> +                             break;
>>               }
>>
>>               /* Switch on type of interrupt we have */