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* [PATCH 1/2] video: ssd1307fb: Use gpiod_set_value_cansleep() for reset
@ 2018-09-19  9:18 ` Michal Vokáč
  0 siblings, 0 replies; 13+ messages in thread
From: Michal Vokáč @ 2018-09-19  9:18 UTC (permalink / raw)
  To: Bartlomiej Zolnierkiewicz, Shawn Guo
  Cc: Fabio Estevam, Rob Herring, devicetree, linux-kernel,
	linux-fbdev, Michal Vokáč

The reset signal can be produced by GPIO expander that can sleep.
In that case the probe function fails. Allow using GPIO expanders for
the reset signal by using the non-atomic gpiod_set_value_cansleep()
function.

Signed-off-by: Michal Vokáč <michal.vokac@ysoft.com>
---
 drivers/video/fbdev/ssd1307fb.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/video/fbdev/ssd1307fb.c b/drivers/video/fbdev/ssd1307fb.c
index ba66c02..e7ae135 100644
--- a/drivers/video/fbdev/ssd1307fb.c
+++ b/drivers/video/fbdev/ssd1307fb.c
@@ -728,9 +728,9 @@ static int ssd1307fb_probe(struct i2c_client *client,
 
 	if (par->reset) {
 		/* Reset the screen */
-		gpiod_set_value(par->reset, 0);
+		gpiod_set_value_cansleep(par->reset, 0);
 		udelay(4);
-		gpiod_set_value(par->reset, 1);
+		gpiod_set_value_cansleep(par->reset, 1);
 		udelay(4);
 	}
 
-- 
2.1.4


^ permalink raw reply related	[flat|nested] 13+ messages in thread
* [PATCH 1/2] video: ssd1307fb: Use gpiod_set_value_cansleep() for reset
@ 2018-09-19  9:18 ` Michal Vokáč
  0 siblings, 0 replies; 13+ messages in thread
From: Michal Vokáč @ 2018-09-19  9:18 UTC (permalink / raw)
  To: Bartlomiej Zolnierkiewicz, Shawn Guo
  Cc: Fabio Estevam, Rob Herring, devicetree, linux-kernel,
	linux-fbdev, Michal Vokáč

The reset signal can be produced by GPIO expander that can sleep.
In that case the probe function fails. Allow using GPIO expanders for
the reset signal by using the non-atomic gpiod_set_value_cansleep()
function.

Signed-off-by: Michal Vokáč <michal.vokac@ysoft.com>
---
 drivers/video/fbdev/ssd1307fb.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/video/fbdev/ssd1307fb.c b/drivers/video/fbdev/ssd1307fb.c
index ba66c02..e7ae135 100644
--- a/drivers/video/fbdev/ssd1307fb.c
+++ b/drivers/video/fbdev/ssd1307fb.c
@@ -728,9 +728,9 @@ static int ssd1307fb_probe(struct i2c_client *client,
 
 	if (par->reset) {
 		/* Reset the screen */
-		gpiod_set_value(par->reset, 0);
+		gpiod_set_value_cansleep(par->reset, 0);
 		udelay(4);
-		gpiod_set_value(par->reset, 1);
+		gpiod_set_value_cansleep(par->reset, 1);
 		udelay(4);
 	}
 
-- 
2.1.4

^ permalink raw reply related	[flat|nested] 13+ messages in thread
* [PATCH 2/2] video: ssd1307fb: Do not hard code active-low reset sequence
  2018-09-19  9:18 ` Michal Vokáč
@ 2018-09-19  9:18   ` Michal Vokáč
  -1 siblings, 0 replies; 13+ messages in thread
From: Michal Vokáč @ 2018-09-19  9:18 UTC (permalink / raw)
  To: Bartlomiej Zolnierkiewicz, Shawn Guo
  Cc: Fabio Estevam, Rob Herring, devicetree, linux-kernel,
	linux-fbdev, Michal Vokáč

The SSD130x OLED display reset signal is active low. Now the reset
sequence is implemented in such a way that users are forced to
define reset-gpios as GPIO_ACTIVE_HIGH in DT to make the reset work.

Do not hard code the active-low sequence into the driver but instead
allow the user to specify the gpio as GPIO_ACTIVE_LOW to reflect
the real world.

The only single in-tree user of the display is converted and builds
fine.

Signed-off-by: Michal Vokáč <michal.vokac@ysoft.com>
---
I am not really sure wheater this should be in one commit or the DT
changes should be done in separate commit. Just tell me and I will
split/merge the changes as you want. Thanks.

 arch/arm/boot/dts/imx28-cfa10036.dts | 3 ++-
 drivers/video/fbdev/ssd1307fb.c      | 4 ++--
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/arch/arm/boot/dts/imx28-cfa10036.dts b/arch/arm/boot/dts/imx28-cfa10036.dts
index e54f5ab..be3406e 100644
--- a/arch/arm/boot/dts/imx28-cfa10036.dts
+++ b/arch/arm/boot/dts/imx28-cfa10036.dts
@@ -11,6 +11,7 @@
 
 /dts-v1/;
 #include "imx28.dtsi"
+#include <dt-bindings/gpio/gpio.h>
 
 / {
 	model = "Crystalfontz CFA-10036 Board";
@@ -95,7 +96,7 @@
 					pinctrl-names = "default";
 					pinctrl-0 = <&ssd1306_cfa10036>;
 					reg = <0x3c>;
-					reset-gpios = <&gpio2 7 0>;
+					reset-gpios = <&gpio2 7 GPIO_ACTIVE_LOW>;
 					solomon,height = <32>;
 					solomon,width = <128>;
 					solomon,page-offset = <0>;
diff --git a/drivers/video/fbdev/ssd1307fb.c b/drivers/video/fbdev/ssd1307fb.c
index e7ae135..7b5bc42 100644
--- a/drivers/video/fbdev/ssd1307fb.c
+++ b/drivers/video/fbdev/ssd1307fb.c
@@ -728,10 +728,10 @@ static int ssd1307fb_probe(struct i2c_client *client,
 
 	if (par->reset) {
 		/* Reset the screen */
-		gpiod_set_value_cansleep(par->reset, 0);
-		udelay(4);
 		gpiod_set_value_cansleep(par->reset, 1);
 		udelay(4);
+		gpiod_set_value_cansleep(par->reset, 0);
+		udelay(4);
 	}
 
 	if (par->vbat_reg) {
-- 
2.1.4


^ permalink raw reply related	[flat|nested] 13+ messages in thread
* [PATCH 2/2] video: ssd1307fb: Do not hard code active-low reset sequence
@ 2018-09-19  9:18   ` Michal Vokáč
  0 siblings, 0 replies; 13+ messages in thread
From: Michal Vokáč @ 2018-09-19  9:18 UTC (permalink / raw)
  To: Bartlomiej Zolnierkiewicz, Shawn Guo
  Cc: Fabio Estevam, Rob Herring, devicetree, linux-kernel,
	linux-fbdev, Michal Vokáč

The SSD130x OLED display reset signal is active low. Now the reset
sequence is implemented in such a way that users are forced to
define reset-gpios as GPIO_ACTIVE_HIGH in DT to make the reset work.

Do not hard code the active-low sequence into the driver but instead
allow the user to specify the gpio as GPIO_ACTIVE_LOW to reflect
the real world.

The only single in-tree user of the display is converted and builds
fine.

Signed-off-by: Michal Vokáč <michal.vokac@ysoft.com>
---
I am not really sure wheater this should be in one commit or the DT
changes should be done in separate commit. Just tell me and I will
split/merge the changes as you want. Thanks.

 arch/arm/boot/dts/imx28-cfa10036.dts | 3 ++-
 drivers/video/fbdev/ssd1307fb.c      | 4 ++--
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/arch/arm/boot/dts/imx28-cfa10036.dts b/arch/arm/boot/dts/imx28-cfa10036.dts
index e54f5ab..be3406e 100644
--- a/arch/arm/boot/dts/imx28-cfa10036.dts
+++ b/arch/arm/boot/dts/imx28-cfa10036.dts
@@ -11,6 +11,7 @@
 
 /dts-v1/;
 #include "imx28.dtsi"
+#include <dt-bindings/gpio/gpio.h>
 
 / {
 	model = "Crystalfontz CFA-10036 Board";
@@ -95,7 +96,7 @@
 					pinctrl-names = "default";
 					pinctrl-0 = <&ssd1306_cfa10036>;
 					reg = <0x3c>;
-					reset-gpios = <&gpio2 7 0>;
+					reset-gpios = <&gpio2 7 GPIO_ACTIVE_LOW>;
 					solomon,height = <32>;
 					solomon,width = <128>;
 					solomon,page-offset = <0>;
diff --git a/drivers/video/fbdev/ssd1307fb.c b/drivers/video/fbdev/ssd1307fb.c
index e7ae135..7b5bc42 100644
--- a/drivers/video/fbdev/ssd1307fb.c
+++ b/drivers/video/fbdev/ssd1307fb.c
@@ -728,10 +728,10 @@ static int ssd1307fb_probe(struct i2c_client *client,
 
 	if (par->reset) {
 		/* Reset the screen */
-		gpiod_set_value_cansleep(par->reset, 0);
-		udelay(4);
 		gpiod_set_value_cansleep(par->reset, 1);
 		udelay(4);
+		gpiod_set_value_cansleep(par->reset, 0);
+		udelay(4);
 	}
 
 	if (par->vbat_reg) {
-- 
2.1.4

^ permalink raw reply related	[flat|nested] 13+ messages in thread
* Re: [PATCH 1/2] video: ssd1307fb: Use gpiod_set_value_cansleep() for reset
  2018-09-19  9:18 ` Michal Vokáč
  (?)
@ 2018-09-19 12:11   ` Fabio Estevam
  -1 siblings, 0 replies; 13+ messages in thread
From: Fabio Estevam @ 2018-09-19 12:11 UTC (permalink / raw)
  To: Michal Vokáč
  Cc: Bartlomiej Zolnierkiewicz, Shawn Guo, Fabio Estevam, Rob Herring,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	linux-kernel, linux-fbdev

Hi Michal,

On Wed, Sep 19, 2018 at 6:18 AM, Michal Vokáč <michal.vokac@ysoft.com> wrote:
> The reset signal can be produced by GPIO expander that can sleep.
> In that case the probe function fails. Allow using GPIO expanders for
> the reset signal by using the non-atomic gpiod_set_value_cansleep()
> function.
>
> Signed-off-by: Michal Vokáč <michal.vokac@ysoft.com>

Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>

^ permalink raw reply	[flat|nested] 13+ messages in thread
* Re: [PATCH 1/2] video: ssd1307fb: Use gpiod_set_value_cansleep() for reset
@ 2018-09-19 12:11   ` Fabio Estevam
  0 siblings, 0 replies; 13+ messages in thread
From: Fabio Estevam @ 2018-09-19 12:11 UTC (permalink / raw)
  To: Michal Vokáč
  Cc: Bartlomiej Zolnierkiewicz, Shawn Guo, Fabio Estevam, Rob Herring,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	linux-kernel, linux-fbdev

Hi Michal,

On Wed, Sep 19, 2018 at 6:18 AM, Michal Vokáč <michal.vokac@ysoft.com> wrote:
> The reset signal can be produced by GPIO expander that can sleep.
> In that case the probe function fails. Allow using GPIO expanders for
> the reset signal by using the non-atomic gpiod_set_value_cansleep()
> function.
>
> Signed-off-by: Michal Vokáč <michal.vokac@ysoft.com>

Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>

^ permalink raw reply	[flat|nested] 13+ messages in thread
* Re: [PATCH 1/2] video: ssd1307fb: Use gpiod_set_value_cansleep() for reset
@ 2018-09-19 12:11   ` Fabio Estevam
  0 siblings, 0 replies; 13+ messages in thread
From: Fabio Estevam @ 2018-09-19 12:11 UTC (permalink / raw)
  To: Michal Vokáč
  Cc: Bartlomiej Zolnierkiewicz, Shawn Guo, Fabio Estevam, Rob Herring,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	linux-kernel, linux-fbdev

Hi Michal,

On Wed, Sep 19, 2018 at 6:18 AM, Michal Vokáč <michal.vokac@ysoft.com> wrote:
> The reset signal can be produced by GPIO expander that can sleep.
> In that case the probe function fails. Allow using GPIO expanders for
> the reset signal by using the non-atomic gpiod_set_value_cansleep()
> function.
>
> Signed-off-by: Michal Vokáč <michal.vokac@ysoft.com>

Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>

^ permalink raw reply	[flat|nested] 13+ messages in thread
* Re: [PATCH 2/2] video: ssd1307fb: Do not hard code active-low reset sequence
  2018-09-19  9:18   ` Michal Vokáč
  (?)
@ 2018-09-19 12:12     ` Fabio Estevam
  -1 siblings, 0 replies; 13+ messages in thread
From: Fabio Estevam @ 2018-09-19 12:12 UTC (permalink / raw)
  To: Michal Vokáč
  Cc: Bartlomiej Zolnierkiewicz, Shawn Guo, Fabio Estevam, Rob Herring,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	linux-kernel, linux-fbdev

Hi Michal,

On Wed, Sep 19, 2018 at 6:18 AM, Michal Vokáč <michal.vokac@ysoft.com> wrote:
> The SSD130x OLED display reset signal is active low. Now the reset
> sequence is implemented in such a way that users are forced to
> define reset-gpios as GPIO_ACTIVE_HIGH in DT to make the reset work.
>
> Do not hard code the active-low sequence into the driver but instead
> allow the user to specify the gpio as GPIO_ACTIVE_LOW to reflect
> the real world.
>
> The only single in-tree user of the display is converted and builds
> fine.
>
> Signed-off-by: Michal Vokáč <michal.vokac@ysoft.com>
> ---
> I am not really sure wheater this should be in one commit or the DT
> changes should be done in separate commit. Just tell me and I will
> split/merge the changes as you want. Thanks.

Please separate in two patches: one for the dts and another for the driver.

Thanks

^ permalink raw reply	[flat|nested] 13+ messages in thread
* Re: [PATCH 2/2] video: ssd1307fb: Do not hard code active-low reset sequence
@ 2018-09-19 12:12     ` Fabio Estevam
  0 siblings, 0 replies; 13+ messages in thread
From: Fabio Estevam @ 2018-09-19 12:12 UTC (permalink / raw)
  To: Michal Vokáč
  Cc: Bartlomiej Zolnierkiewicz, Shawn Guo, Fabio Estevam, Rob Herring,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	linux-kernel, linux-fbdev

Hi Michal,

On Wed, Sep 19, 2018 at 6:18 AM, Michal Vokáč <michal.vokac@ysoft.com> wrote:
> The SSD130x OLED display reset signal is active low. Now the reset
> sequence is implemented in such a way that users are forced to
> define reset-gpios as GPIO_ACTIVE_HIGH in DT to make the reset work.
>
> Do not hard code the active-low sequence into the driver but instead
> allow the user to specify the gpio as GPIO_ACTIVE_LOW to reflect
> the real world.
>
> The only single in-tree user of the display is converted and builds
> fine.
>
> Signed-off-by: Michal Vokáč <michal.vokac@ysoft.com>
> ---
> I am not really sure wheater this should be in one commit or the DT
> changes should be done in separate commit. Just tell me and I will
> split/merge the changes as you want. Thanks.

Please separate in two patches: one for the dts and another for the driver.

Thanks

^ permalink raw reply	[flat|nested] 13+ messages in thread
* Re: [PATCH 2/2] video: ssd1307fb: Do not hard code active-low reset sequence
@ 2018-09-19 12:12     ` Fabio Estevam
  0 siblings, 0 replies; 13+ messages in thread
From: Fabio Estevam @ 2018-09-19 12:12 UTC (permalink / raw)
  To: Michal Vokáč
  Cc: Bartlomiej Zolnierkiewicz, Shawn Guo, Fabio Estevam, Rob Herring,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	linux-kernel, linux-fbdev

Hi Michal,

On Wed, Sep 19, 2018 at 6:18 AM, Michal Vokáč <michal.vokac@ysoft.com> wrote:
> The SSD130x OLED display reset signal is active low. Now the reset
> sequence is implemented in such a way that users are forced to
> define reset-gpios as GPIO_ACTIVE_HIGH in DT to make the reset work.
>
> Do not hard code the active-low sequence into the driver but instead
> allow the user to specify the gpio as GPIO_ACTIVE_LOW to reflect
> the real world.
>
> The only single in-tree user of the display is converted and builds
> fine.
>
> Signed-off-by: Michal Vokáč <michal.vokac@ysoft.com>
> ---
> I am not really sure wheater this should be in one commit or the DT
> changes should be done in separate commit. Just tell me and I will
> split/merge the changes as you want. Thanks.

Please separate in two patches: one for the dts and another for the driver.

Thanks

^ permalink raw reply	[flat|nested] 13+ messages in thread
* Re: [PATCH 2/2] video: ssd1307fb: Do not hard code active-low reset sequence
  2018-09-19 12:12     ` Fabio Estevam
  (?)
@ 2018-09-19 12:57       ` Michal Vokáč
  -1 siblings, 0 replies; 13+ messages in thread
From: Michal Vokáč @ 2018-09-19 12:57 UTC (permalink / raw)
  To: Fabio Estevam
  Cc: Bartlomiej Zolnierkiewicz, Shawn Guo, Fabio Estevam, Rob Herring,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	linux-kernel, linux-fbdev

On 19.9.2018 14:12, Fabio Estevam wrote:
> Hi Michal,
> 
> On Wed, Sep 19, 2018 at 6:18 AM, Michal Vokáč <michal.vokac@ysoft.com> wrote:
>> The SSD130x OLED display reset signal is active low. Now the reset
>> sequence is implemented in such a way that users are forced to
>> define reset-gpios as GPIO_ACTIVE_HIGH in DT to make the reset work.
>>
>> Do not hard code the active-low sequence into the driver but instead
>> allow the user to specify the gpio as GPIO_ACTIVE_LOW to reflect
>> the real world.
>>
>> The only single in-tree user of the display is converted and builds
>> fine.
>>
>> Signed-off-by: Michal Vokáč <michal.vokac@ysoft.com>
>> ---
>> I am not really sure wheater this should be in one commit or the DT
>> changes should be done in separate commit. Just tell me and I will
>> split/merge the changes as you want. Thanks.
> 
> Please separate in two patches: one for the dts and another for the driver.

OK, thank you. I will send v2 shortly.

Michal


^ permalink raw reply	[flat|nested] 13+ messages in thread
* Re: [PATCH 2/2] video: ssd1307fb: Do not hard code active-low reset sequence
@ 2018-09-19 12:57       ` Michal Vokáč
  0 siblings, 0 replies; 13+ messages in thread
From: Michal Vokáč @ 2018-09-19 12:57 UTC (permalink / raw)
  To: Fabio Estevam
  Cc: Bartlomiej Zolnierkiewicz, Shawn Guo, Fabio Estevam, Rob Herring,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	linux-kernel, linux-fbdev

On 19.9.2018 14:12, Fabio Estevam wrote:
> Hi Michal,
> 
> On Wed, Sep 19, 2018 at 6:18 AM, Michal Vokáč <michal.vokac@ysoft.com> wrote:
>> The SSD130x OLED display reset signal is active low. Now the reset
>> sequence is implemented in such a way that users are forced to
>> define reset-gpios as GPIO_ACTIVE_HIGH in DT to make the reset work.
>>
>> Do not hard code the active-low sequence into the driver but instead
>> allow the user to specify the gpio as GPIO_ACTIVE_LOW to reflect
>> the real world.
>>
>> The only single in-tree user of the display is converted and builds
>> fine.
>>
>> Signed-off-by: Michal Vokáč <michal.vokac@ysoft.com>
>> ---
>> I am not really sure wheater this should be in one commit or the DT
>> changes should be done in separate commit. Just tell me and I will
>> split/merge the changes as you want. Thanks.
> 
> Please separate in two patches: one for the dts and another for the driver.

OK, thank you. I will send v2 shortly.

Michal

^ permalink raw reply	[flat|nested] 13+ messages in thread
* Re: [PATCH 2/2] video: ssd1307fb: Do not hard code active-low reset sequence
@ 2018-09-19 12:57       ` Michal Vokáč
  0 siblings, 0 replies; 13+ messages in thread
From: Michal Vokáč @ 2018-09-19 12:57 UTC (permalink / raw)
  To: Fabio Estevam
  Cc: Bartlomiej Zolnierkiewicz, Shawn Guo, Fabio Estevam, Rob Herring,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	linux-kernel, linux-fbdev

On 19.9.2018 14:12, Fabio Estevam wrote:
> Hi Michal,
> 
> On Wed, Sep 19, 2018 at 6:18 AM, Michal Vokáč <michal.vokac@ysoft.com> wrote:
>> The SSD130x OLED display reset signal is active low. Now the reset
>> sequence is implemented in such a way that users are forced to
>> define reset-gpios as GPIO_ACTIVE_HIGH in DT to make the reset work.
>>
>> Do not hard code the active-low sequence into the driver but instead
>> allow the user to specify the gpio as GPIO_ACTIVE_LOW to reflect
>> the real world.
>>
>> The only single in-tree user of the display is converted and builds
>> fine.
>>
>> Signed-off-by: Michal Vokáč <michal.vokac@ysoft.com>
>> ---
>> I am not really sure wheater this should be in one commit or the DT
>> changes should be done in separate commit. Just tell me and I will
>> split/merge the changes as you want. Thanks.
> 
> Please separate in two patches: one for the dts and another for the driver.

OK, thank you. I will send v2 shortly.

Michal

^ permalink raw reply	[flat|nested] 13+ messages in thread
end of thread, other threads:[~2018-09-19 12:57 UTC | newest]

Thread overview: 13+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-09-19  9:18 [PATCH 1/2] video: ssd1307fb: Use gpiod_set_value_cansleep() for reset Michal Vokáč
2018-09-19  9:18 ` Michal Vokáč
2018-09-19  9:18 ` [PATCH 2/2] video: ssd1307fb: Do not hard code active-low reset sequence Michal Vokáč
2018-09-19  9:18   ` Michal Vokáč
2018-09-19 12:12   ` Fabio Estevam
2018-09-19 12:12     ` Fabio Estevam
2018-09-19 12:12     ` Fabio Estevam
2018-09-19 12:57     ` Michal Vokáč
2018-09-19 12:57       ` Michal Vokáč
2018-09-19 12:57       ` Michal Vokáč
2018-09-19 12:11 ` [PATCH 1/2] video: ssd1307fb: Use gpiod_set_value_cansleep() for reset Fabio Estevam
2018-09-19 12:11   ` Fabio Estevam
2018-09-19 12:11   ` Fabio Estevam

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