[2/2] i2c: i801: Replace waitqueue with completion API

Message ID 1d1054de-8b47-a6bb-a264-8456705e5875@gmail.com
State New
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Series
  • i2c: i801: Replace waitqueue with completion API
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Commit Message

Heiner Kallweit May 21, 2021, 10:02 p.m.
Using the completion API is more intuitive and it allows to simplify
the code. Note that we don't have to set priv->status = 0 any longer
with the completion API.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 drivers/i2c/busses/i2c-i801.c | 48 ++++++++++++++---------------------
 1 file changed, 19 insertions(+), 29 deletions(-)

Comments

Jean Delvare May 25, 2021, 12:12 p.m. | #1
Hi Heiner,

Adding Daniel Kurtz, who wrote the original wait queue-based code, to
Cc. I'm not sure if Daniel is still into kernel code though.

On Sat, 22 May 2021 00:02:43 +0200, Heiner Kallweit wrote:
> Using the completion API is more intuitive and it allows to simplify

> the code. Note that we don't have to set priv->status = 0 any longer

> with the completion API.


OK, but you need to call reinit_completion() instead, which has the
same cost. So that's not a good argument ;-)

> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>

> ---

>  drivers/i2c/busses/i2c-i801.c | 48 ++++++++++++++---------------------

>  1 file changed, 19 insertions(+), 29 deletions(-)

> 

> diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c

> index bfea94d02..738204d77 100644

> --- a/drivers/i2c/busses/i2c-i801.c

> +++ b/drivers/i2c/busses/i2c-i801.c

> @@ -103,7 +103,7 @@

>  #include <linux/dmi.h>

>  #include <linux/slab.h>

>  #include <linux/string.h>

> -#include <linux/wait.h>

> +#include <linux/completion.h>

>  #include <linux/err.h>

>  #include <linux/platform_device.h>

>  #include <linux/platform_data/itco_wdt.h>

> @@ -270,7 +270,7 @@ struct i801_priv {

>  	unsigned int features;

>  

>  	/* isr processing */

> -	wait_queue_head_t waitq;

> +	struct completion done;

>  	u8 status;

>  

>  	/* Command state used by isr for byte-by-byte block transactions */

> @@ -496,24 +496,19 @@ static int i801_wait_byte_done(struct i801_priv *priv)

>  static int i801_transaction(struct i801_priv *priv, int xact)

>  {

>  	int status;

> -	int result;

> +	unsigned long result;

>  	const struct i2c_adapter *adap = &priv->adapter;

>  

> -	result = i801_check_pre(priv);

> -	if (result < 0)

> -		return result;

> +	status = i801_check_pre(priv);

> +	if (status < 0)

> +		return status;

>  

>  	if (priv->features & FEATURE_IRQ) {

> +		reinit_completion(&priv->done);

>  		outb_p(xact | SMBHSTCNT_INTREN | SMBHSTCNT_START,

>  		       SMBHSTCNT(priv));

> -		result = wait_event_timeout(priv->waitq,

> -					    (status = priv->status),

> -					    adap->timeout);

> -		if (!result)

> -			status = -ETIMEDOUT;

> -

> -		priv->status = 0;

> -		return i801_check_post(priv, status);

> +		result = wait_for_completion_timeout(&priv->done, adap->timeout);

> +		return i801_check_post(priv, result ? priv->status : -ETIMEDOUT);

>  	}

>  

>  	/* the current contents of SMBHSTCNT can be overwritten, since PEC,

> @@ -638,7 +633,7 @@ static irqreturn_t i801_host_notify_isr(struct i801_priv *priv)

>   *      DEV_ERR - Invalid command, NAK or communication timeout

>   *      BUS_ERR - SMI# transaction collision

>   *      FAILED - transaction was canceled due to a KILL request

> - *    When any of these occur, update ->status and wake up the waitq.

> + *    When any of these occur, update ->status and signal completion.

>   *    ->status must be cleared before kicking off the next transaction.

>   *

>   * 2) For byte-by-byte (I2C read/write) transactions, one BYTE_DONE interrupt

> @@ -675,7 +670,7 @@ static irqreturn_t i801_isr(int irq, void *dev_id)

>  	if (status) {

>  		outb_p(status, SMBHSTSTS(priv));

>  		priv->status = status;

> -		wake_up(&priv->waitq);

> +		complete(&priv->done);

>  	}

>  

>  	return IRQ_HANDLED;

> @@ -694,15 +689,15 @@ static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,

>  	int i, len;

>  	int smbcmd;

>  	int status;

> -	int result;

> +	unsigned long result;

>  	const struct i2c_adapter *adap = &priv->adapter;

>  

>  	if (command == I2C_SMBUS_BLOCK_PROC_CALL)

>  		return -EOPNOTSUPP;

>  

> -	result = i801_check_pre(priv);

> -	if (result < 0)

> -		return result;

> +	status = i801_check_pre(priv);

> +	if (status < 0)

> +		return status;

>  

>  	len = data->block[0];

>  

> @@ -726,15 +721,10 @@ static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,

>  		priv->count = 0;

>  		priv->data = &data->block[1];

>  

> +		reinit_completion(&priv->done);

>  		outb_p(priv->cmd | SMBHSTCNT_START, SMBHSTCNT(priv));

> -		result = wait_event_timeout(priv->waitq,

> -					    (status = priv->status),

> -					    adap->timeout);

> -		if (!result)

> -			status = -ETIMEDOUT;

> -

> -		priv->status = 0;

> -		return i801_check_post(priv, status);

> +		result = wait_for_completion_timeout(&priv->done, adap->timeout);

> +		return i801_check_post(priv, result ? priv->status : -ETIMEDOUT);

>  	}

>  

>  	for (i = 1; i <= len; i++) {

> @@ -1889,7 +1879,7 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)

>  	}

>  

>  	if (priv->features & FEATURE_IRQ) {

> -		init_waitqueue_head(&priv->waitq);

> +		init_completion(&priv->done);

>  

>  		err = devm_request_irq(&dev->dev, dev->irq, i801_isr,

>  				       IRQF_SHARED,


The clean-up isn't massive but I agree the code is a bit more pleasant
to read after the change, and I also see the binary size shrink a bit,
so I vote for it.

Reviewed-by: Jean Delvare <jdelvare@suse.de>

Tested-by: Jean Delvare <jdelvare@suse.de>


-- 
Jean Delvare
SUSE L3 Support
Heiner Kallweit May 25, 2021, 1:01 p.m. | #2
On 25.05.2021 14:12, Jean Delvare wrote:
> Hi Heiner,

> 

> Adding Daniel Kurtz, who wrote the original wait queue-based code, to

> Cc. I'm not sure if Daniel is still into kernel code though.

> 

> On Sat, 22 May 2021 00:02:43 +0200, Heiner Kallweit wrote:

>> Using the completion API is more intuitive and it allows to simplify

>> the code. Note that we don't have to set priv->status = 0 any longer

>> with the completion API.

> 

> OK, but you need to call reinit_completion() instead, which has the

> same cost. So that's not a good argument ;-)

> 

Maybe my comment wasn't clear enough. I didn't want to say that we
save something but that it's safe from a functional point of view
to remove clearing priv->status.

>> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>

>> ---

>>  drivers/i2c/busses/i2c-i801.c | 48 ++++++++++++++---------------------

>>  1 file changed, 19 insertions(+), 29 deletions(-)

>>

>> diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c

>> index bfea94d02..738204d77 100644

>> --- a/drivers/i2c/busses/i2c-i801.c

>> +++ b/drivers/i2c/busses/i2c-i801.c

>> @@ -103,7 +103,7 @@

>>  #include <linux/dmi.h>

>>  #include <linux/slab.h>

>>  #include <linux/string.h>

>> -#include <linux/wait.h>

>> +#include <linux/completion.h>

>>  #include <linux/err.h>

>>  #include <linux/platform_device.h>

>>  #include <linux/platform_data/itco_wdt.h>

>> @@ -270,7 +270,7 @@ struct i801_priv {

>>  	unsigned int features;

>>  

>>  	/* isr processing */

>> -	wait_queue_head_t waitq;

>> +	struct completion done;

>>  	u8 status;

>>  

>>  	/* Command state used by isr for byte-by-byte block transactions */

>> @@ -496,24 +496,19 @@ static int i801_wait_byte_done(struct i801_priv *priv)

>>  static int i801_transaction(struct i801_priv *priv, int xact)

>>  {

>>  	int status;

>> -	int result;

>> +	unsigned long result;

>>  	const struct i2c_adapter *adap = &priv->adapter;

>>  

>> -	result = i801_check_pre(priv);

>> -	if (result < 0)

>> -		return result;

>> +	status = i801_check_pre(priv);

>> +	if (status < 0)

>> +		return status;

>>  

>>  	if (priv->features & FEATURE_IRQ) {

>> +		reinit_completion(&priv->done);

>>  		outb_p(xact | SMBHSTCNT_INTREN | SMBHSTCNT_START,

>>  		       SMBHSTCNT(priv));

>> -		result = wait_event_timeout(priv->waitq,

>> -					    (status = priv->status),

>> -					    adap->timeout);

>> -		if (!result)

>> -			status = -ETIMEDOUT;

>> -

>> -		priv->status = 0;

>> -		return i801_check_post(priv, status);

>> +		result = wait_for_completion_timeout(&priv->done, adap->timeout);

>> +		return i801_check_post(priv, result ? priv->status : -ETIMEDOUT);

>>  	}

>>  

>>  	/* the current contents of SMBHSTCNT can be overwritten, since PEC,

>> @@ -638,7 +633,7 @@ static irqreturn_t i801_host_notify_isr(struct i801_priv *priv)

>>   *      DEV_ERR - Invalid command, NAK or communication timeout

>>   *      BUS_ERR - SMI# transaction collision

>>   *      FAILED - transaction was canceled due to a KILL request

>> - *    When any of these occur, update ->status and wake up the waitq.

>> + *    When any of these occur, update ->status and signal completion.

>>   *    ->status must be cleared before kicking off the next transaction.

>>   *

>>   * 2) For byte-by-byte (I2C read/write) transactions, one BYTE_DONE interrupt

>> @@ -675,7 +670,7 @@ static irqreturn_t i801_isr(int irq, void *dev_id)

>>  	if (status) {

>>  		outb_p(status, SMBHSTSTS(priv));

>>  		priv->status = status;

>> -		wake_up(&priv->waitq);

>> +		complete(&priv->done);

>>  	}

>>  

>>  	return IRQ_HANDLED;

>> @@ -694,15 +689,15 @@ static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,

>>  	int i, len;

>>  	int smbcmd;

>>  	int status;

>> -	int result;

>> +	unsigned long result;

>>  	const struct i2c_adapter *adap = &priv->adapter;

>>  

>>  	if (command == I2C_SMBUS_BLOCK_PROC_CALL)

>>  		return -EOPNOTSUPP;

>>  

>> -	result = i801_check_pre(priv);

>> -	if (result < 0)

>> -		return result;

>> +	status = i801_check_pre(priv);

>> +	if (status < 0)

>> +		return status;

>>  

>>  	len = data->block[0];

>>  

>> @@ -726,15 +721,10 @@ static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,

>>  		priv->count = 0;

>>  		priv->data = &data->block[1];

>>  

>> +		reinit_completion(&priv->done);

>>  		outb_p(priv->cmd | SMBHSTCNT_START, SMBHSTCNT(priv));

>> -		result = wait_event_timeout(priv->waitq,

>> -					    (status = priv->status),

>> -					    adap->timeout);

>> -		if (!result)

>> -			status = -ETIMEDOUT;

>> -

>> -		priv->status = 0;

>> -		return i801_check_post(priv, status);

>> +		result = wait_for_completion_timeout(&priv->done, adap->timeout);

>> +		return i801_check_post(priv, result ? priv->status : -ETIMEDOUT);

>>  	}

>>  

>>  	for (i = 1; i <= len; i++) {

>> @@ -1889,7 +1879,7 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)

>>  	}

>>  

>>  	if (priv->features & FEATURE_IRQ) {

>> -		init_waitqueue_head(&priv->waitq);

>> +		init_completion(&priv->done);

>>  

>>  		err = devm_request_irq(&dev->dev, dev->irq, i801_isr,

>>  				       IRQF_SHARED,

> 

> The clean-up isn't massive but I agree the code is a bit more pleasant

> to read after the change, and I also see the binary size shrink a bit,

> so I vote for it.

> 

> Reviewed-by: Jean Delvare <jdelvare@suse.de>

> Tested-by: Jean Delvare <jdelvare@suse.de>

>
Daniel Kurtz May 27, 2021, 7:13 a.m. | #3
Hi Jean, Heiner,

On Tue, May 25, 2021 at 11:01 PM Heiner Kallweit <hkallweit1@gmail.com> wrote:
>

> On 25.05.2021 14:12, Jean Delvare wrote:

> > Hi Heiner,

> >

> > Adding Daniel Kurtz, who wrote the original wait queue-based code, to

> > Cc. I'm not sure if Daniel is still into kernel code though.


Thanks for thinking of me!  I'm still into kernel code, but I do a lot
more reading than writing these days.

> >

> > On Sat, 22 May 2021 00:02:43 +0200, Heiner Kallweit wrote:

> >> Using the completion API is more intuitive and it allows to simplify

> >> the code. Note that we don't have to set priv->status = 0 any longer

> >> with the completion API.

> >

> > OK, but you need to call reinit_completion() instead, which has the

> > same cost. So that's not a good argument ;-)

> >

> Maybe my comment wasn't clear enough. I didn't want to say that we

> save something but that it's safe from a functional point of view

> to remove clearing priv->status.

>

> >> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>

> >> ---

> >>  drivers/i2c/busses/i2c-i801.c | 48 ++++++++++++++---------------------

> >>  1 file changed, 19 insertions(+), 29 deletions(-)

> >>

> >> diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c

> >> index bfea94d02..738204d77 100644

> >> --- a/drivers/i2c/busses/i2c-i801.c

> >> +++ b/drivers/i2c/busses/i2c-i801.c

> >> @@ -103,7 +103,7 @@

> >>  #include <linux/dmi.h>

> >>  #include <linux/slab.h>

> >>  #include <linux/string.h>

> >> -#include <linux/wait.h>

> >> +#include <linux/completion.h>

> >>  #include <linux/err.h>

> >>  #include <linux/platform_device.h>

> >>  #include <linux/platform_data/itco_wdt.h>

> >> @@ -270,7 +270,7 @@ struct i801_priv {

> >>      unsigned int features;

> >>

> >>      /* isr processing */

> >> -    wait_queue_head_t waitq;

> >> +    struct completion done;

> >>      u8 status;

> >>

> >>      /* Command state used by isr for byte-by-byte block transactions */

> >> @@ -496,24 +496,19 @@ static int i801_wait_byte_done(struct i801_priv *priv)

> >>  static int i801_transaction(struct i801_priv *priv, int xact)

> >>  {

> >>      int status;

> >> -    int result;

> >> +    unsigned long result;

> >>      const struct i2c_adapter *adap = &priv->adapter;

> >>

> >> -    result = i801_check_pre(priv);

> >> -    if (result < 0)

> >> -            return result;

> >> +    status = i801_check_pre(priv);

> >> +    if (status < 0)

> >> +            return status;

> >>

> >>      if (priv->features & FEATURE_IRQ) {

> >> +            reinit_completion(&priv->done);

> >>              outb_p(xact | SMBHSTCNT_INTREN | SMBHSTCNT_START,

> >>                     SMBHSTCNT(priv));

> >> -            result = wait_event_timeout(priv->waitq,

> >> -                                        (status = priv->status),

> >> -                                        adap->timeout);

> >> -            if (!result)

> >> -                    status = -ETIMEDOUT;

> >> -

> >> -            priv->status = 0;

> >> -            return i801_check_post(priv, status);

> >> +            result = wait_for_completion_timeout(&priv->done, adap->timeout);

> >> +            return i801_check_post(priv, result ? priv->status : -ETIMEDOUT);

> >>      }

> >>

> >>      /* the current contents of SMBHSTCNT can be overwritten, since PEC,

> >> @@ -638,7 +633,7 @@ static irqreturn_t i801_host_notify_isr(struct i801_priv *priv)

> >>   *      DEV_ERR - Invalid command, NAK or communication timeout

> >>   *      BUS_ERR - SMI# transaction collision

> >>   *      FAILED - transaction was canceled due to a KILL request

> >> - *    When any of these occur, update ->status and wake up the waitq.

> >> + *    When any of these occur, update ->status and signal completion.

> >>   *    ->status must be cleared before kicking off the next transaction.

> >>   *

> >>   * 2) For byte-by-byte (I2C read/write) transactions, one BYTE_DONE interrupt

> >> @@ -675,7 +670,7 @@ static irqreturn_t i801_isr(int irq, void *dev_id)

> >>      if (status) {

> >>              outb_p(status, SMBHSTSTS(priv));

> >>              priv->status = status;

> >> -            wake_up(&priv->waitq);

> >> +            complete(&priv->done);

> >>      }

> >>

> >>      return IRQ_HANDLED;

> >> @@ -694,15 +689,15 @@ static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,

> >>      int i, len;

> >>      int smbcmd;

> >>      int status;

> >> -    int result;

> >> +    unsigned long result;

> >>      const struct i2c_adapter *adap = &priv->adapter;

> >>

> >>      if (command == I2C_SMBUS_BLOCK_PROC_CALL)

> >>              return -EOPNOTSUPP;

> >>

> >> -    result = i801_check_pre(priv);

> >> -    if (result < 0)

> >> -            return result;

> >> +    status = i801_check_pre(priv);

> >> +    if (status < 0)

> >> +            return status;

> >>

> >>      len = data->block[0];

> >>

> >> @@ -726,15 +721,10 @@ static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,

> >>              priv->count = 0;

> >>              priv->data = &data->block[1];

> >>

> >> +            reinit_completion(&priv->done);

> >>              outb_p(priv->cmd | SMBHSTCNT_START, SMBHSTCNT(priv));

> >> -            result = wait_event_timeout(priv->waitq,

> >> -                                        (status = priv->status),

> >> -                                        adap->timeout);

> >> -            if (!result)

> >> -                    status = -ETIMEDOUT;

> >> -

> >> -            priv->status = 0;

> >> -            return i801_check_post(priv, status);

> >> +            result = wait_for_completion_timeout(&priv->done, adap->timeout);

> >> +            return i801_check_post(priv, result ? priv->status : -ETIMEDOUT);

> >>      }

> >>

> >>      for (i = 1; i <= len; i++) {

> >> @@ -1889,7 +1879,7 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)

> >>      }

> >>

> >>      if (priv->features & FEATURE_IRQ) {

> >> -            init_waitqueue_head(&priv->waitq);

> >> +            init_completion(&priv->done);

> >>

> >>              err = devm_request_irq(&dev->dev, dev->irq, i801_isr,

> >>                                     IRQF_SHARED,

> >

> > The clean-up isn't massive but I agree the code is a bit more pleasant

> > to read after the change, and I also see the binary size shrink a bit,

> > so I vote for it.

> >

> > Reviewed-by: Jean Delvare <jdelvare@suse.de>

> > Tested-by: Jean Delvare <jdelvare@suse.de>

> >

>


I agree, shorter and sweeter. Thanks for cleaning this up!

Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Wolfram Sang May 27, 2021, 8:09 p.m. | #4
On Sat, May 22, 2021 at 12:02:43AM +0200, Heiner Kallweit wrote:
> Using the completion API is more intuitive and it allows to simplify

> the code. Note that we don't have to set priv->status = 0 any longer

> with the completion API.

> 

> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>


Applied to for-next, thanks!

Patch

diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index bfea94d02..738204d77 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -103,7 +103,7 @@ 
 #include <linux/dmi.h>
 #include <linux/slab.h>
 #include <linux/string.h>
-#include <linux/wait.h>
+#include <linux/completion.h>
 #include <linux/err.h>
 #include <linux/platform_device.h>
 #include <linux/platform_data/itco_wdt.h>
@@ -270,7 +270,7 @@  struct i801_priv {
 	unsigned int features;
 
 	/* isr processing */
-	wait_queue_head_t waitq;
+	struct completion done;
 	u8 status;
 
 	/* Command state used by isr for byte-by-byte block transactions */
@@ -496,24 +496,19 @@  static int i801_wait_byte_done(struct i801_priv *priv)
 static int i801_transaction(struct i801_priv *priv, int xact)
 {
 	int status;
-	int result;
+	unsigned long result;
 	const struct i2c_adapter *adap = &priv->adapter;
 
-	result = i801_check_pre(priv);
-	if (result < 0)
-		return result;
+	status = i801_check_pre(priv);
+	if (status < 0)
+		return status;
 
 	if (priv->features & FEATURE_IRQ) {
+		reinit_completion(&priv->done);
 		outb_p(xact | SMBHSTCNT_INTREN | SMBHSTCNT_START,
 		       SMBHSTCNT(priv));
-		result = wait_event_timeout(priv->waitq,
-					    (status = priv->status),
-					    adap->timeout);
-		if (!result)
-			status = -ETIMEDOUT;
-
-		priv->status = 0;
-		return i801_check_post(priv, status);
+		result = wait_for_completion_timeout(&priv->done, adap->timeout);
+		return i801_check_post(priv, result ? priv->status : -ETIMEDOUT);
 	}
 
 	/* the current contents of SMBHSTCNT can be overwritten, since PEC,
@@ -638,7 +633,7 @@  static irqreturn_t i801_host_notify_isr(struct i801_priv *priv)
  *      DEV_ERR - Invalid command, NAK or communication timeout
  *      BUS_ERR - SMI# transaction collision
  *      FAILED - transaction was canceled due to a KILL request
- *    When any of these occur, update ->status and wake up the waitq.
+ *    When any of these occur, update ->status and signal completion.
  *    ->status must be cleared before kicking off the next transaction.
  *
  * 2) For byte-by-byte (I2C read/write) transactions, one BYTE_DONE interrupt
@@ -675,7 +670,7 @@  static irqreturn_t i801_isr(int irq, void *dev_id)
 	if (status) {
 		outb_p(status, SMBHSTSTS(priv));
 		priv->status = status;
-		wake_up(&priv->waitq);
+		complete(&priv->done);
 	}
 
 	return IRQ_HANDLED;
@@ -694,15 +689,15 @@  static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,
 	int i, len;
 	int smbcmd;
 	int status;
-	int result;
+	unsigned long result;
 	const struct i2c_adapter *adap = &priv->adapter;
 
 	if (command == I2C_SMBUS_BLOCK_PROC_CALL)
 		return -EOPNOTSUPP;
 
-	result = i801_check_pre(priv);
-	if (result < 0)
-		return result;
+	status = i801_check_pre(priv);
+	if (status < 0)
+		return status;
 
 	len = data->block[0];
 
@@ -726,15 +721,10 @@  static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,
 		priv->count = 0;
 		priv->data = &data->block[1];
 
+		reinit_completion(&priv->done);
 		outb_p(priv->cmd | SMBHSTCNT_START, SMBHSTCNT(priv));
-		result = wait_event_timeout(priv->waitq,
-					    (status = priv->status),
-					    adap->timeout);
-		if (!result)
-			status = -ETIMEDOUT;
-
-		priv->status = 0;
-		return i801_check_post(priv, status);
+		result = wait_for_completion_timeout(&priv->done, adap->timeout);
+		return i801_check_post(priv, result ? priv->status : -ETIMEDOUT);
 	}
 
 	for (i = 1; i <= len; i++) {
@@ -1889,7 +1879,7 @@  static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
 	}
 
 	if (priv->features & FEATURE_IRQ) {
-		init_waitqueue_head(&priv->waitq);
+		init_completion(&priv->done);
 
 		err = devm_request_irq(&dev->dev, dev->irq, i801_isr,
 				       IRQF_SHARED,