diff mbox series

[v2,1/4] spi: s3c64xx: changed to PIO mode if there is no DMA

Message ID 20230419060639.38853-2-jaewon02.kim@samsung.com (mailing list archive)
State New, archived
Headers show
Series [v2,1/4] spi: s3c64xx: changed to PIO mode if there is no DMA | expand

Commit Message

Jaewon Kim April 19, 2023, 6:06 a.m. UTC
Polling mode supported with qurik if there was no DMA in the SOC.
However, there are cased where we cannot or do not want to use DMA.
To support this case, if DMA is not set, it is switched to polling mode.

Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
---
 drivers/spi/spi-s3c64xx.c                 | 8 ++++++--
 include/linux/platform_data/spi-s3c64xx.h | 1 +
 2 files changed, 7 insertions(+), 2 deletions(-)

Comments

Krzysztof Kozlowski April 19, 2023, 8:03 a.m. UTC | #1
On 19/04/2023 08:06, Jaewon Kim wrote:
> Polling mode supported with qurik if there was no DMA in the SOC.

typo: quirk
You missed verb in your first part of sentence. I don't understand it.

> However, there are cased where we cannot or do not want to use DMA.
> To support this case, if DMA is not set, it is switched to polling mode.
> 
> Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
> ---
>  drivers/spi/spi-s3c64xx.c                 | 8 ++++++--
>  include/linux/platform_data/spi-s3c64xx.h | 1 +
>  2 files changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
> index 71d324ec9a70..273aa02322d9 100644
> --- a/drivers/spi/spi-s3c64xx.c
> +++ b/drivers/spi/spi-s3c64xx.c
> @@ -19,7 +19,6 @@
>  #include <linux/platform_data/spi-s3c64xx.h>
>  
>  #define MAX_SPI_PORTS		12
> -#define S3C64XX_SPI_QUIRK_POLL		(1 << 0)
>  #define S3C64XX_SPI_QUIRK_CS_AUTO	(1 << 1)
>  #define AUTOSUSPEND_TIMEOUT	2000
>  
> @@ -116,7 +115,7 @@
>  #define S3C64XX_SPI_TRAILCNT		S3C64XX_SPI_MAX_TRAILCNT
>  
>  #define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
> -#define is_polling(x)	(x->port_conf->quirks & S3C64XX_SPI_QUIRK_POLL)
> +#define is_polling(x)	(x->cntrlr_info->polling)
>  
>  #define RXBUSY    (1<<2)
>  #define TXBUSY    (1<<3)
> @@ -1067,6 +1066,11 @@ static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
>  		sci->num_cs = temp;
>  	}
>  
> +	if (!of_find_property(dev->of_node, "dmas", NULL)) {
> +		dev_warn(dev, "cannot find DMA, changed to PIO mode\n");

You said it is desired option, so should not be a warning. I would make
it debug at most.

> +		sci->polling = 1;



Best regards,
Krzysztof
Jaewon Kim April 19, 2023, 8:31 a.m. UTC | #2
On 23. 4. 19. 17:03, Krzysztof Kozlowski wrote:
> On 19/04/2023 08:06, Jaewon Kim wrote:
>> Polling mode supported with qurik if there was no DMA in the SOC.
> typo: quirk
> You missed verb in your first part of sentence. I don't understand it.

Sorry, I change this sentence like below.

Polling mode supported as a quirk for SOCs without DMA.

>
>> However, there are cased where we cannot or do not want to use DMA.
>> To support this case, if DMA is not set, it is switched to polling mode.
>>
>> Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
>> ---
>>   drivers/spi/spi-s3c64xx.c                 | 8 ++++++--
>>   include/linux/platform_data/spi-s3c64xx.h | 1 +
>>   2 files changed, 7 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
>> index 71d324ec9a70..273aa02322d9 100644
>> --- a/drivers/spi/spi-s3c64xx.c
>> +++ b/drivers/spi/spi-s3c64xx.c
>> @@ -19,7 +19,6 @@
>>   #include <linux/platform_data/spi-s3c64xx.h>
>>   
>>   #define MAX_SPI_PORTS		12
>> -#define S3C64XX_SPI_QUIRK_POLL		(1 << 0)
>>   #define S3C64XX_SPI_QUIRK_CS_AUTO	(1 << 1)
>>   #define AUTOSUSPEND_TIMEOUT	2000
>>   
>> @@ -116,7 +115,7 @@
>>   #define S3C64XX_SPI_TRAILCNT		S3C64XX_SPI_MAX_TRAILCNT
>>   
>>   #define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
>> -#define is_polling(x)	(x->port_conf->quirks & S3C64XX_SPI_QUIRK_POLL)
>> +#define is_polling(x)	(x->cntrlr_info->polling)
>>   
>>   #define RXBUSY    (1<<2)
>>   #define TXBUSY    (1<<3)
>> @@ -1067,6 +1066,11 @@ static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
>>   		sci->num_cs = temp;
>>   	}
>>   
>> +	if (!of_find_property(dev->of_node, "dmas", NULL)) {
>> +		dev_warn(dev, "cannot find DMA, changed to PIO mode\n");
> You said it is desired option, so should not be a warning. I would make
> it debug at most.
>
Okay, I will change dev_warn() to dev_dbg().


>> +		sci->polling = 1;
>
>
> Best regards,
> Krzysztof
>
>

Thanks

Jaewon Kim
Krzysztof Kozlowski April 19, 2023, 8:36 a.m. UTC | #3
On 19/04/2023 10:31, Jaewon Kim wrote:
> 
> On 23. 4. 19. 17:03, Krzysztof Kozlowski wrote:
>> On 19/04/2023 08:06, Jaewon Kim wrote:
>>> Polling mode supported with qurik if there was no DMA in the SOC.
>> typo: quirk
>> You missed verb in your first part of sentence. I don't understand it.
> 
> Sorry, I change this sentence like below.
> 
> Polling mode supported as a quirk for SOCs without DMA.

I would say still verb is missing as supported in past tense does not
make sense.

See:
https://elixir.bootlin.com/linux/v5.17.1/source/Documentation/process/submitting-patches.rst#L95

> 


Best regards,
Krzysztof
Andi Shyti April 19, 2023, 3:46 p.m. UTC | #4
Hi Jaewon,

On Wed, Apr 19, 2023 at 03:06:36PM +0900, Jaewon Kim wrote:
> Polling mode supported with qurik if there was no DMA in the SOC.

I think you want to say here that "Through quirks we choose to
use polling mode whenever there is no DMA in the SoC".

> However, there are cased where we cannot or do not want to use DMA.

/cased/cases/

> To support this case, if DMA is not set, it is switched to polling mode.

You haven't really described what you are doing here... you could
just write something like: "Use DTS properties to select wether
to use polling or DMA mode."

Side note, please use the imperative form when you want to
describe what you have done to fix the issue.

> Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
> ---
>  drivers/spi/spi-s3c64xx.c                 | 8 ++++++--
>  include/linux/platform_data/spi-s3c64xx.h | 1 +
>  2 files changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
> index 71d324ec9a70..273aa02322d9 100644
> --- a/drivers/spi/spi-s3c64xx.c
> +++ b/drivers/spi/spi-s3c64xx.c
> @@ -19,7 +19,6 @@
>  #include <linux/platform_data/spi-s3c64xx.h>
>  
>  #define MAX_SPI_PORTS		12
> -#define S3C64XX_SPI_QUIRK_POLL		(1 << 0)
>  #define S3C64XX_SPI_QUIRK_CS_AUTO	(1 << 1)
>  #define AUTOSUSPEND_TIMEOUT	2000
>  
> @@ -116,7 +115,7 @@
>  #define S3C64XX_SPI_TRAILCNT		S3C64XX_SPI_MAX_TRAILCNT
>  
>  #define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
> -#define is_polling(x)	(x->port_conf->quirks & S3C64XX_SPI_QUIRK_POLL)
> +#define is_polling(x)	(x->cntrlr_info->polling)
>  
>  #define RXBUSY    (1<<2)
>  #define TXBUSY    (1<<3)
> @@ -1067,6 +1066,11 @@ static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
>  		sci->num_cs = temp;
>  	}
>  
> +	if (!of_find_property(dev->of_node, "dmas", NULL)) {
> +		dev_warn(dev, "cannot find DMA, changed to PIO mode\n");
> +		sci->polling = 1;

	sci->polling = true;

But it could be even better:

	sci->polling = !of_find_property(dev->of_node, "dmas", NULL));

and you get rid of the dev_warn() that is not required.

Andi
Krzysztof Kozlowski April 20, 2023, 3:40 p.m. UTC | #5
On 19/04/2023 08:06, Jaewon Kim wrote:
> Polling mode supported with qurik if there was no DMA in the SOC.
> However, there are cased where we cannot or do not want to use DMA.
> To support this case, if DMA is not set, it is switched to polling mode.
> 

(...)

>  #define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
> -#define is_polling(x)	(x->port_conf->quirks & S3C64XX_SPI_QUIRK_POLL)
> +#define is_polling(x)	(x->cntrlr_info->polling)
>  
>  #define RXBUSY    (1<<2)
>  #define TXBUSY    (1<<3)
> @@ -1067,6 +1066,11 @@ static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
>  		sci->num_cs = temp;
>  	}
>  
> +	if (!of_find_property(dev->of_node, "dmas", NULL)) {

of_property_present()


Best regards,
Krzysztof
Jaewon Kim April 21, 2023, 1:43 a.m. UTC | #6
Hi Andi,


On 23. 4. 20. 00:46, Andi Shyti wrote:
> Hi Jaewon,
>
> On Wed, Apr 19, 2023 at 03:06:36PM +0900, Jaewon Kim wrote:
>> Polling mode supported with qurik if there was no DMA in the SOC.
> I think you want to say here that "Through quirks we choose to
> use polling mode whenever there is no DMA in the SoC".
>
>> However, there are cased where we cannot or do not want to use DMA.
> /cased/cases/
>
>> To support this case, if DMA is not set, it is switched to polling mode.
> You haven't really described what you are doing here... you could
> just write something like: "Use DTS properties to select wether
> to use polling or DMA mode."
>
> Side note, please use the imperative form when you want to
> describe what you have done to fix the issue.


Thanks for guide.

I will change description in v3.


>
>> Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
>> ---
>>   drivers/spi/spi-s3c64xx.c                 | 8 ++++++--
>>   include/linux/platform_data/spi-s3c64xx.h | 1 +
>>   2 files changed, 7 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
>> index 71d324ec9a70..273aa02322d9 100644
>> --- a/drivers/spi/spi-s3c64xx.c
>> +++ b/drivers/spi/spi-s3c64xx.c
>> @@ -19,7 +19,6 @@
>>   #include <linux/platform_data/spi-s3c64xx.h>
>>   
>>   #define MAX_SPI_PORTS		12
>> -#define S3C64XX_SPI_QUIRK_POLL		(1 << 0)
>>   #define S3C64XX_SPI_QUIRK_CS_AUTO	(1 << 1)
>>   #define AUTOSUSPEND_TIMEOUT	2000
>>   
>> @@ -116,7 +115,7 @@
>>   #define S3C64XX_SPI_TRAILCNT		S3C64XX_SPI_MAX_TRAILCNT
>>   
>>   #define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
>> -#define is_polling(x)	(x->port_conf->quirks & S3C64XX_SPI_QUIRK_POLL)
>> +#define is_polling(x)	(x->cntrlr_info->polling)
>>   
>>   #define RXBUSY    (1<<2)
>>   #define TXBUSY    (1<<3)
>> @@ -1067,6 +1066,11 @@ static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
>>   		sci->num_cs = temp;
>>   	}
>>   
>> +	if (!of_find_property(dev->of_node, "dmas", NULL)) {
>> +		dev_warn(dev, "cannot find DMA, changed to PIO mode\n");
>> +		sci->polling = 1;
> 	sci->polling = true;
>
> But it could be even better:
>
> 	sci->polling = !of_find_property(dev->of_node, "dmas", NULL));
>
> and you get rid of the dev_warn() that is not required.
>
> Andi


Okay, I will change 1 to 'true'..


Thanks

Jaewon Kim
Jaewon Kim April 21, 2023, 1:45 a.m. UTC | #7
On 23. 4. 21. 00:40, Krzysztof Kozlowski wrote:
> On 19/04/2023 08:06, Jaewon Kim wrote:
>> Polling mode supported with qurik if there was no DMA in the SOC.
>> However, there are cased where we cannot or do not want to use DMA.
>> To support this case, if DMA is not set, it is switched to polling mode.
>>
> (...)
>
>>   #define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
>> -#define is_polling(x)	(x->port_conf->quirks & S3C64XX_SPI_QUIRK_POLL)
>> +#define is_polling(x)	(x->cntrlr_info->polling)
>>   
>>   #define RXBUSY    (1<<2)
>>   #define TXBUSY    (1<<3)
>> @@ -1067,6 +1066,11 @@ static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
>>   		sci->num_cs = temp;
>>   	}
>>   
>> +	if (!of_find_property(dev->of_node, "dmas", NULL)) {
> of_property_present()

I will change it to of_property_present().


>
> Best regards,
> Krzysztof
>
>
Thanks

Jaewon Kim
diff mbox series

Patch

diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index 71d324ec9a70..273aa02322d9 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -19,7 +19,6 @@ 
 #include <linux/platform_data/spi-s3c64xx.h>
 
 #define MAX_SPI_PORTS		12
-#define S3C64XX_SPI_QUIRK_POLL		(1 << 0)
 #define S3C64XX_SPI_QUIRK_CS_AUTO	(1 << 1)
 #define AUTOSUSPEND_TIMEOUT	2000
 
@@ -116,7 +115,7 @@ 
 #define S3C64XX_SPI_TRAILCNT		S3C64XX_SPI_MAX_TRAILCNT
 
 #define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
-#define is_polling(x)	(x->port_conf->quirks & S3C64XX_SPI_QUIRK_POLL)
+#define is_polling(x)	(x->cntrlr_info->polling)
 
 #define RXBUSY    (1<<2)
 #define TXBUSY    (1<<3)
@@ -1067,6 +1066,11 @@  static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
 		sci->num_cs = temp;
 	}
 
+	if (!of_find_property(dev->of_node, "dmas", NULL)) {
+		dev_warn(dev, "cannot find DMA, changed to PIO mode\n");
+		sci->polling = 1;
+	}
+
 	sci->no_cs = of_property_read_bool(dev->of_node, "no-cs-readback");
 
 	return sci;
diff --git a/include/linux/platform_data/spi-s3c64xx.h b/include/linux/platform_data/spi-s3c64xx.h
index 5df1ace6d2c9..cb7b8ddc899f 100644
--- a/include/linux/platform_data/spi-s3c64xx.h
+++ b/include/linux/platform_data/spi-s3c64xx.h
@@ -35,6 +35,7 @@  struct s3c64xx_spi_info {
 	int src_clk_nr;
 	int num_cs;
 	bool no_cs;
+	bool polling;
 	int (*cfg_gpio)(void);
 };