diff mbox

[11/11] spi-dw: remove noop else clause

Message ID 1308794413-11069-12-git-send-email-dirk.brandewie@gmail.com
State Superseded, archived
Headers show

Commit Message

dirk.brandewie@gmail.com June 23, 2011, 2 a.m. UTC
From: Dirk Brandewie <dirk.brandewie@gmail.com>

The value of spi->bits_per_word is checked on function entry to be 8
or 16.  The else clause has no meaning since it can never be reached.

Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
---
 drivers/spi/spi-dw.c |    9 +++------
 1 files changed, 3 insertions(+), 6 deletions(-)

Comments

Feng Tang June 23, 2011, 2:47 a.m. UTC | #1
On Thu, 23 Jun 2011 10:00:13 +0800
"dirk.brandewie@gmail.com" <dirk.brandewie@gmail.com> wrote:

> From: Dirk Brandewie <dirk.brandewie@gmail.com>
> 
> The value of spi->bits_per_word is checked on function entry to be 8
> or 16.  The else clause has no meaning since it can never be reached.
> 
> Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
> ---
>  drivers/spi/spi-dw.c |    9 +++------
>  1 files changed, 3 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c
> index 7b3f607..5ddd45f 100644
> --- a/drivers/spi/spi-dw.c
> +++ b/drivers/spi/spi-dw.c
> @@ -667,17 +667,14 @@ static int spi_dw_setup(struct spi_device *spi)
>  		chip->enable_dma = chip_info->enable_dma;
>  	}
>  
> -	if (spi->bits_per_word <= 8) {
> +	if (spi->bits_per_word == 8) {
>  		chip->n_bytes = 1;
>  		chip->dma_width = 1;
> -	} else if (spi->bits_per_word <= 16) {
> +	} else if (spi->bits_per_word == 16) {
>  		chip->n_bytes = 2;
>  		chip->dma_width = 2;
> -	} else {
> -		/* Never take >16b case for DW SPIC */
> -		dev_err(&spi->dev, "invalid wordsize\n");
> -		return -EINVAL;
>  	}

These "else" case is used to ban the slave spi devices which
try to use 32 bits per word mode. This is like to tell those
spi devices with 32 bpw capability "we don't support 32b, pls
change"

> +
>  	chip->bits_per_word = spi->bits_per_word;
>  
>  	chip->speed_hz = spi->max_speed_hz;

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dirk.brandewie@gmail.com June 23, 2011, 3:13 a.m. UTC | #2
On 06/22/2011 07:47 PM, Feng Tang wrote:
> On Thu, 23 Jun 2011 10:00:13 +0800
> "dirk.brandewie@gmail.com"<dirk.brandewie@gmail.com>  wrote:
>
>> From: Dirk Brandewie<dirk.brandewie@gmail.com>
>>
>> The value of spi->bits_per_word is checked on function entry to be 8
>> or 16.  The else clause has no meaning since it can never be reached.
>>
>> Signed-off-by: Dirk Brandewie<dirk.brandewie@gmail.com>
>> ---
>>   drivers/spi/spi-dw.c |    9 +++------
>>   1 files changed, 3 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c
>> index 7b3f607..5ddd45f 100644
>> --- a/drivers/spi/spi-dw.c
>> +++ b/drivers/spi/spi-dw.c
>> @@ -667,17 +667,14 @@ static int spi_dw_setup(struct spi_device *spi)
>>   		chip->enable_dma = chip_info->enable_dma;
>>   	}
>>
>> -	if (spi->bits_per_word<= 8) {
>> +	if (spi->bits_per_word == 8) {
>>   		chip->n_bytes = 1;
>>   		chip->dma_width = 1;
>> -	} else if (spi->bits_per_word<= 16) {
>> +	} else if (spi->bits_per_word == 16) {
>>   		chip->n_bytes = 2;
>>   		chip->dma_width = 2;
>> -	} else {
>> -		/* Never take>16b case for DW SPIC */
>> -		dev_err(&spi->dev, "invalid wordsize\n");
>> -		return -EINVAL;
>>   	}
>
> These "else" case is used to ban the slave spi devices which
> try to use 32 bits per word mode. This is like to tell those
> spi devices with 32 bpw capability "we don't support 32b, pls
> change"

The function has the prerequisite code:
	if (spi->bits_per_word != 8 && spi->bits_per_word != 16)
		return -EINVAL;

at the begining of the function so we will never be able to reach the else 
clause that is being removed.

>
>> +
>>   	chip->bits_per_word = spi->bits_per_word;
>>
>>   	chip->speed_hz = spi->max_speed_hz;


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Installation's a snap, and flexible recovery options mean your data is safe,
secure and there when you need it. Data protection magic?
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diff mbox

Patch

diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c
index 7b3f607..5ddd45f 100644
--- a/drivers/spi/spi-dw.c
+++ b/drivers/spi/spi-dw.c
@@ -667,17 +667,14 @@  static int spi_dw_setup(struct spi_device *spi)
 		chip->enable_dma = chip_info->enable_dma;
 	}
 
-	if (spi->bits_per_word <= 8) {
+	if (spi->bits_per_word == 8) {
 		chip->n_bytes = 1;
 		chip->dma_width = 1;
-	} else if (spi->bits_per_word <= 16) {
+	} else if (spi->bits_per_word == 16) {
 		chip->n_bytes = 2;
 		chip->dma_width = 2;
-	} else {
-		/* Never take >16b case for DW SPIC */
-		dev_err(&spi->dev, "invalid wordsize\n");
-		return -EINVAL;
 	}
+
 	chip->bits_per_word = spi->bits_per_word;
 
 	chip->speed_hz = spi->max_speed_hz;