Re: [PATCH 4/5] [media] winbond-cir: One variable and its check less in wbcir_shutdown() after error detection

2016-10-19 Thread SF Markus Elfring 
 + /* Set CEIR_EN */
 + wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_CTL, 0x01, 0x01);
 +set_irqmask:
 /*
 * ACPI will set the HW disable bit for SP3 which means that the
 * output signals are left in an undefined state which may cause
 @@ -876,6 +858,14 @@ wbcir_shutdown(struct pnp_dev *device)
 */
 wbcir_set_irqmask(data, WBCIR_IRQ_NONE);
 disable_irq(data->irq);
 + return;
 +clear_bits:
 + /* Clear BUFF_EN, Clear END_EN, Clear MATCH_EN */
 + wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_EV_EN, 0x00, 0x07);
 +
 + /* Clear CEIR_EN */
 + wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_CTL, 0x00, 0x01);
 + goto set_irqmask;
>>>
>>> I'm not convinced that adding a goto which goes backwards is making this
>>> code any more readible, just so that a local variable can be dropped.
>>
>> Thanks for your feedback.
>>
>> Is such a "backward jump" usual and finally required when you would like
>> to move a bit of common error handling code to the end without using extra
>> local variables and a few statements should still be performed after it?
>>
> 
> I'm sorry, I can't parse this.

Can an other update suggestion like "[PATCH 6/6] crypto-caamhash:
Move common error handling code in two functions" explain this technique
a bit better in principle?
https://patchwork.kernel.org/patch/9333861/
https://lkml.kernel.org/r/

Regards,
Markus

Re: [PATCH 4/5] [media] winbond-cir: One variable and its check less in wbcir_shutdown() after error detection

2016-10-19 Thread David Härdeman 
October 15, 2016 3:30 PM, "Sean Young"  wrote:
> On Fri, Oct 14, 2016 at 01:44:02PM +0200, SF Markus Elfring wrote:
> 
>> From: Markus Elfring 
>> Date: Fri, 14 Oct 2016 12:48:41 +0200
>> 
>> The local variable "do_wake" was set to "false" after an invalid system
>> setting was detected so that a bit of error handling was triggered.
>> 
>> * Replace these assignments by direct jumps to the source code with the
>> desired exception handling.
>> 
>> * Delete this status variable and a corresponding check which became
>> unnecessary with this refactoring.
>> 
>> Signed-off-by: Markus Elfring 
>> ---
>> drivers/media/rc/winbond-cir.c | 78 
>> ++
>> 1 file changed, 34 insertions(+), 44 deletions(-)
>> 
>> diff --git a/drivers/media/rc/winbond-cir.c b/drivers/media/rc/winbond-cir.c
>> index 9d05e17..3d286b9 100644
>> --- a/drivers/media/rc/winbond-cir.c
>> +++ b/drivers/media/rc/winbond-cir.c
>> @@ -699,16 +699,13 @@ wbcir_shutdown(struct pnp_dev *device)
>> {
>> struct device *dev = &device->dev;
>> struct wbcir_data *data = pnp_get_drvdata(device);
>> - bool do_wake = true;
>> u8 match[11];
>> u8 mask[11];
>> u8 rc6_csl;
>> int i;
>> 
>> - if (wake_sc == INVALID_SCANCODE || !device_may_wakeup(dev)) {
>> - do_wake = false;
>> - goto finish;
>> - }
>> + if (wake_sc == INVALID_SCANCODE || !device_may_wakeup(dev))
>> + goto clear_bits;
>> 
>> rc6_csl = 0;
>> memset(match, 0, sizeof(match));
>> @@ -716,9 +713,8 @@ wbcir_shutdown(struct pnp_dev *device)
>> switch (protocol) {
>> case IR_PROTOCOL_RC5:
>> if (wake_sc > 0xFFF) {
>> - do_wake = false;
>> dev_err(dev, "RC5 - Invalid wake scancode\n");
>> - break;
>> + goto clear_bits;
>> }
>> 
>> /* Mask = 13 bits, ex toggle */
>> @@ -735,9 +731,8 @@ wbcir_shutdown(struct pnp_dev *device)
>> 
>> case IR_PROTOCOL_NEC:
>> if (wake_sc > 0xFF) {
>> - do_wake = false;
>> dev_err(dev, "NEC - Invalid wake scancode\n");
>> - break;
>> + goto clear_bits;
>> }
>> 
>> mask[0] = mask[1] = mask[2] = mask[3] = 0xFF;
>> @@ -757,9 +752,8 @@ wbcir_shutdown(struct pnp_dev *device)
>> 
>> if (wake_rc6mode == 0) {
>> if (wake_sc > 0x) {
>> - do_wake = false;
>> dev_err(dev, "RC6 - Invalid wake scancode\n");
>> - break;
>> + goto clear_bits;
>> }
>> 
>> /* Command */
>> @@ -813,9 +807,8 @@ wbcir_shutdown(struct pnp_dev *device)
>> } else if (wake_sc <= 0x007F) {
>> rc6_csl = 60;
>> } else {
>> - do_wake = false;
>> dev_err(dev, "RC6 - Invalid wake scancode\n");
>> - break;
>> + goto clear_bits;
>> }
>> 
>> /* Header */
>> @@ -825,49 +818,38 @@ wbcir_shutdown(struct pnp_dev *device)
>> mask[i++] = 0x0F;
>> 
>> } else {
>> - do_wake = false;
>> dev_err(dev, "RC6 - Invalid wake mode\n");
>> + goto clear_bits;
>> }
>> 
>> break;
>> 
>> default:
>> - do_wake = false;
>> - break;
>> + goto clear_bits;
>> }
>> 
>> -finish:
>> - if (do_wake) {
>> - /* Set compare and compare mask */
>> - wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_INDEX,
>> - WBCIR_REGSEL_COMPARE | WBCIR_REG_ADDR0,
>> - 0x3F);
>> - outsb(data->wbase + WBCIR_REG_WCEIR_DATA, match, 11);
>> - wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_INDEX,
>> - WBCIR_REGSEL_MASK | WBCIR_REG_ADDR0,
>> - 0x3F);
>> - outsb(data->wbase + WBCIR_REG_WCEIR_DATA, mask, 11);
>> -
>> - /* RC6 Compare String Len */
>> - outb(rc6_csl, data->wbase + WBCIR_REG_WCEIR_CSL);
>> -
>> - /* Clear status bits NEC_REP, BUFF, MSG_END, MATCH */
>> - wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_STS, 0x17, 0x17);
>> + /* Set compare and compare mask */
>> + wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_INDEX,
>> + WBCIR_REGSEL_COMPARE | WBCIR_REG_ADDR0,
>> + 0x3F);
>> + outsb(data->wbase + WBCIR_REG_WCEIR_DATA, match, 11);
>> + wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_INDEX,
>> + WBCIR_REGSEL_MASK | WBCIR_REG_ADDR0,
>> + 0x3F);
>> + outsb(data->wbase + WBCIR_REG_WCEIR_DATA, mask, 11);
>> 
>> - /* Clear BUFF_EN, Clear END_EN, Set MATCH_EN */
>> - wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_EV_EN, 0x01, 0x07);
>> + /* RC6 Compare String Len */
>> + outb(rc6_csl, data->wbase + WBCIR_REG_WCEIR_CSL);
>> 
>> - /* Set CEIR_EN */
>> - wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_CTL, 0x01, 0x01);
>> -
>> - } else {
>> - /* Clear BUFF_EN, Clear END_EN, Clear MATCH_EN */
>> - wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_EV_EN, 0x00, 0x07);
>> + /* Clear status bits NEC_REP, BUFF, MSG_END, MATCH */
>> + wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_STS, 0x17, 0x17);
>> 
>> - /* Clear CEIR_EN */
>> - wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_CTL, 0x00, 0x01);
>> - }
>> + /* Clear BUFF_EN, Clear END_EN, Set MATCH_EN */
>> + wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_EV_EN, 0x01, 0x07);
>> 
>> + /* Set CEIR_EN */
>> + wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_CTL, 0x01, 0x01);
>> +set_irqmask:
>> /*
>> * ACPI will set the HW disable bit for SP3 which means that the
>> * output signals are left in an undefined state which may cause
>> @@ -876,6 +858,14 @@ wbcir_shutdown(struct pnp_dev *device)
>> */
>> wbcir_set_irqmask(data,

Re: [PATCH 4/5] [media] winbond-cir: One variable and its check less in wbcir_shutdown() after error detection

2016-10-19 Thread David Härdeman 
October 15, 2016 6:42 PM, "SF Markus Elfring"  
wrote:
>>> + /* Set CEIR_EN */
>>> + wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_CTL, 0x01, 0x01);
>>> +set_irqmask:
>>> /*
>>> * ACPI will set the HW disable bit for SP3 which means that the
>>> * output signals are left in an undefined state which may cause
>>> @@ -876,6 +858,14 @@ wbcir_shutdown(struct pnp_dev *device)
>>> */
>>> wbcir_set_irqmask(data, WBCIR_IRQ_NONE);
>>> disable_irq(data->irq);
>>> + return;
>>> +clear_bits:
>>> + /* Clear BUFF_EN, Clear END_EN, Clear MATCH_EN */
>>> + wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_EV_EN, 0x00, 0x07);
>>> +
>>> + /* Clear CEIR_EN */
>>> + wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_CTL, 0x00, 0x01);
>>> + goto set_irqmask;
>> 
>> I'm not convinced that adding a goto which goes backwards is making this
>> code any more readible, just so that a local variable can be dropped.
> 
> Thanks for your feedback.
> 
> Is such a "backward jump" usual and finally required when you would like
> to move a bit of common error handling code to the end without using extra
> local variables and a few statements should still be performed after it?
> 

I'm sorry, I can't parse this.

Re: [PATCH 4/5] [media] winbond-cir: One variable and its check less in wbcir_shutdown() after error detection

2016-10-15 Thread SF Markus Elfring 
>> +/* Set CEIR_EN */
>> +wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_CTL, 0x01, 0x01);
>> +set_irqmask:
>>  /*
>>   * ACPI will set the HW disable bit for SP3 which means that the
>>   * output signals are left in an undefined state which may cause
>> @@ -876,6 +858,14 @@ wbcir_shutdown(struct pnp_dev *device)
>>   */
>>  wbcir_set_irqmask(data, WBCIR_IRQ_NONE);
>>  disable_irq(data->irq);
>> +return;
>> +clear_bits:
>> +/* Clear BUFF_EN, Clear END_EN, Clear MATCH_EN */
>> +wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_EV_EN, 0x00, 0x07);
>> +
>> +/* Clear CEIR_EN */
>> +wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_CTL, 0x00, 0x01);
>> +goto set_irqmask;
> 
> I'm not convinced that adding a goto which goes backwards is making this
> code any more readible, just so that a local variable can be dropped.

Thanks for your feedback.

Is such a "backward jump" usual and finally required when you would like
to move a bit of common error handling code to the end without using extra
local variables and a few statements should still be performed after it?

Regards,
Markus

Re: [PATCH 4/5] [media] winbond-cir: One variable and its check less in wbcir_shutdown() after error detection

2016-10-15 Thread Sean Young 
On Fri, Oct 14, 2016 at 01:44:02PM +0200, SF Markus Elfring wrote:
> From: Markus Elfring 
> Date: Fri, 14 Oct 2016 12:48:41 +0200
> 
> The local variable "do_wake" was set to "false" after an invalid system
> setting was detected so that a bit of error handling was triggered.
> 
> * Replace these assignments by direct jumps to the source code with the
> desired exception handling.
> 
> * Delete this status variable and a corresponding check which became
>   unnecessary with this refactoring.
> 
> Signed-off-by: Markus Elfring 
> ---
>  drivers/media/rc/winbond-cir.c | 78 
> ++
>  1 file changed, 34 insertions(+), 44 deletions(-)
> 
> diff --git a/drivers/media/rc/winbond-cir.c b/drivers/media/rc/winbond-cir.c
> index 9d05e17..3d286b9 100644
> --- a/drivers/media/rc/winbond-cir.c
> +++ b/drivers/media/rc/winbond-cir.c
> @@ -699,16 +699,13 @@ wbcir_shutdown(struct pnp_dev *device)
>  {
>   struct device *dev = &device->dev;
>   struct wbcir_data *data = pnp_get_drvdata(device);
> - bool do_wake = true;
>   u8 match[11];
>   u8 mask[11];
>   u8 rc6_csl;
>   int i;
>  
> - if (wake_sc == INVALID_SCANCODE || !device_may_wakeup(dev)) {
> - do_wake = false;
> - goto finish;
> - }
> + if (wake_sc == INVALID_SCANCODE || !device_may_wakeup(dev))
> + goto clear_bits;
>  
>   rc6_csl = 0;
>   memset(match, 0, sizeof(match));
> @@ -716,9 +713,8 @@ wbcir_shutdown(struct pnp_dev *device)
>   switch (protocol) {
>   case IR_PROTOCOL_RC5:
>   if (wake_sc > 0xFFF) {
> - do_wake = false;
>   dev_err(dev, "RC5 - Invalid wake scancode\n");
> - break;
> + goto clear_bits;
>   }
>  
>   /* Mask = 13 bits, ex toggle */
> @@ -735,9 +731,8 @@ wbcir_shutdown(struct pnp_dev *device)
>  
>   case IR_PROTOCOL_NEC:
>   if (wake_sc > 0xFF) {
> - do_wake = false;
>   dev_err(dev, "NEC - Invalid wake scancode\n");
> - break;
> + goto clear_bits;
>   }
>  
>   mask[0] = mask[1] = mask[2] = mask[3] = 0xFF;
> @@ -757,9 +752,8 @@ wbcir_shutdown(struct pnp_dev *device)
>  
>   if (wake_rc6mode == 0) {
>   if (wake_sc > 0x) {
> - do_wake = false;
>   dev_err(dev, "RC6 - Invalid wake scancode\n");
> - break;
> + goto clear_bits;
>   }
>  
>   /* Command */
> @@ -813,9 +807,8 @@ wbcir_shutdown(struct pnp_dev *device)
>   } else if (wake_sc <= 0x007F) {
>   rc6_csl = 60;
>   } else {
> - do_wake = false;
>   dev_err(dev, "RC6 - Invalid wake scancode\n");
> - break;
> + goto clear_bits;
>   }
>  
>   /* Header */
> @@ -825,49 +818,38 @@ wbcir_shutdown(struct pnp_dev *device)
>   mask[i++] = 0x0F;
>  
>   } else {
> - do_wake = false;
>   dev_err(dev, "RC6 - Invalid wake mode\n");
> + goto clear_bits;
>   }
>  
>   break;
>  
>   default:
> - do_wake = false;
> - break;
> + goto clear_bits;
>   }
>  
> -finish:
> - if (do_wake) {
> - /* Set compare and compare mask */
> - wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_INDEX,
> -WBCIR_REGSEL_COMPARE | WBCIR_REG_ADDR0,
> -0x3F);
> - outsb(data->wbase + WBCIR_REG_WCEIR_DATA, match, 11);
> - wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_INDEX,
> -WBCIR_REGSEL_MASK | WBCIR_REG_ADDR0,
> -0x3F);
> - outsb(data->wbase + WBCIR_REG_WCEIR_DATA, mask, 11);
> -
> - /* RC6 Compare String Len */
> - outb(rc6_csl, data->wbase + WBCIR_REG_WCEIR_CSL);
> -
> - /* Clear status bits NEC_REP, BUFF, MSG_END, MATCH */
> - wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_STS, 0x17, 0x17);
> + /* Set compare and compare mask */
> + wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_INDEX,
> +WBCIR_REGSEL_COMPARE | WBCIR_REG_ADDR0,
> +0x3F);
> + outsb(data->wbase + WBCIR_REG_WCEIR_DATA, match, 11);
> + wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_INDEX,
> +WBCIR_REGSEL_MASK | WBCIR_REG_ADDR0,
> +0x3F);
> + outsb(data->wbase + WBCIR_REG_WCEIR_DATA, mask, 11);
>  
> - /* Clear BUFF_EN,

[PATCH 4/5] [media] winbond-cir: One variable and its check less in wbcir_shutdown() after error detection

2016-10-14 Thread SF Markus Elfring 
From: Markus Elfring 
Date: Fri, 14 Oct 2016 12:48:41 +0200

The local variable "do_wake" was set to "false" after an invalid system
setting was detected so that a bit of error handling was triggered.

* Replace these assignments by direct jumps to the source code with the
desired exception handling.

* Delete this status variable and a corresponding check which became
  unnecessary with this refactoring.

Signed-off-by: Markus Elfring 
---
 drivers/media/rc/winbond-cir.c | 78 ++
 1 file changed, 34 insertions(+), 44 deletions(-)

diff --git a/drivers/media/rc/winbond-cir.c b/drivers/media/rc/winbond-cir.c
index 9d05e17..3d286b9 100644
--- a/drivers/media/rc/winbond-cir.c
+++ b/drivers/media/rc/winbond-cir.c
@@ -699,16 +699,13 @@ wbcir_shutdown(struct pnp_dev *device)
 {
struct device *dev = &device->dev;
struct wbcir_data *data = pnp_get_drvdata(device);
-   bool do_wake = true;
u8 match[11];
u8 mask[11];
u8 rc6_csl;
int i;
 
-   if (wake_sc == INVALID_SCANCODE || !device_may_wakeup(dev)) {
-   do_wake = false;
-   goto finish;
-   }
+   if (wake_sc == INVALID_SCANCODE || !device_may_wakeup(dev))
+   goto clear_bits;
 
rc6_csl = 0;
memset(match, 0, sizeof(match));
@@ -716,9 +713,8 @@ wbcir_shutdown(struct pnp_dev *device)
switch (protocol) {
case IR_PROTOCOL_RC5:
if (wake_sc > 0xFFF) {
-   do_wake = false;
dev_err(dev, "RC5 - Invalid wake scancode\n");
-   break;
+   goto clear_bits;
}
 
/* Mask = 13 bits, ex toggle */
@@ -735,9 +731,8 @@ wbcir_shutdown(struct pnp_dev *device)
 
case IR_PROTOCOL_NEC:
if (wake_sc > 0xFF) {
-   do_wake = false;
dev_err(dev, "NEC - Invalid wake scancode\n");
-   break;
+   goto clear_bits;
}
 
mask[0] = mask[1] = mask[2] = mask[3] = 0xFF;
@@ -757,9 +752,8 @@ wbcir_shutdown(struct pnp_dev *device)
 
if (wake_rc6mode == 0) {
if (wake_sc > 0x) {
-   do_wake = false;
dev_err(dev, "RC6 - Invalid wake scancode\n");
-   break;
+   goto clear_bits;
}
 
/* Command */
@@ -813,9 +807,8 @@ wbcir_shutdown(struct pnp_dev *device)
} else if (wake_sc <= 0x007F) {
rc6_csl = 60;
} else {
-   do_wake = false;
dev_err(dev, "RC6 - Invalid wake scancode\n");
-   break;
+   goto clear_bits;
}
 
/* Header */
@@ -825,49 +818,38 @@ wbcir_shutdown(struct pnp_dev *device)
mask[i++] = 0x0F;
 
} else {
-   do_wake = false;
dev_err(dev, "RC6 - Invalid wake mode\n");
+   goto clear_bits;
}
 
break;
 
default:
-   do_wake = false;
-   break;
+   goto clear_bits;
}
 
-finish:
-   if (do_wake) {
-   /* Set compare and compare mask */
-   wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_INDEX,
-  WBCIR_REGSEL_COMPARE | WBCIR_REG_ADDR0,
-  0x3F);
-   outsb(data->wbase + WBCIR_REG_WCEIR_DATA, match, 11);
-   wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_INDEX,
-  WBCIR_REGSEL_MASK | WBCIR_REG_ADDR0,
-  0x3F);
-   outsb(data->wbase + WBCIR_REG_WCEIR_DATA, mask, 11);
-
-   /* RC6 Compare String Len */
-   outb(rc6_csl, data->wbase + WBCIR_REG_WCEIR_CSL);
-
-   /* Clear status bits NEC_REP, BUFF, MSG_END, MATCH */
-   wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_STS, 0x17, 0x17);
+   /* Set compare and compare mask */
+   wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_INDEX,
+  WBCIR_REGSEL_COMPARE | WBCIR_REG_ADDR0,
+  0x3F);
+   outsb(data->wbase + WBCIR_REG_WCEIR_DATA, match, 11);
+   wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_INDEX,
+  WBCIR_REGSEL_MASK | WBCIR_REG_ADDR0,
+  0x3F);
+   outsb(data->wbase + WBCIR_REG_WCEIR_DATA, mask, 11);
 
-   /* Clear BUFF_EN, Clear END_EN, Set MATCH_EN */
-   wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_EV_EN, 0x01, 0x07);
+   /* RC6 Compare String Len */
+   o