fbdev/ssd1307fb: Some changes and improvement

PATCH In review Jyri Sarha 4 participants 14 messages Jan 13, 2017 – Feb 8, 2017 6 messages not in the archive

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Jyri Sarha

author

2017-01-13 10:35 UTC #0 lore raw

v2 cover fbdev/ssd1307fb: Some changes and improvement

Changes since first version:
- Cherry-picked "fbdev/ssd1307fb: add support to enable VBAT" again beacuse of weird mixup in the first version
- Also tested the code on top of v4.10-rc3 with am335x-icev2 evm

We needed these changes for couple of our evm. Some of these patches have been on mainline list before, but after that forgotten. Now we are forward porting these on for out internal release, so this is a good time to get them to mainline too.

Everything else is quite straight forward, but removing the reset-active-low dts property is a questionable at least in theory. However, in practice if anyone was using the property in their device-tree blobs, they have never been able to get desired effect with mainline kernel.

Jyri Sarha (3):
fbdev: ssd1307fb: Start to use gpiod API for reset gpio
fbdev: ssd1307fb: Remove reset-active-low from the DT binding document
fbdev: ssd1307fb: Make reset gpio devicetree property optional

Tomi Valkeinen (2):
fbdev/ssd1307fb: add support to enable VBAT
fbdev/ssd1307fb: clear screen in probe

 .../devicetree/bindings/display/ssd1307fb.txt      |  5 +-
 drivers/video/fbdev/ssd1307fb.c                    | 55 ++++++++++++++--------
 2 files changed, 38 insertions(+), 22 deletions(-)

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Jyri Sarha

author

2017-01-13 10:35 UTC #2 lore raw

PATCH v2 1/5 fbdev: ssd1307fb: Start to use gpiod API for reset gpio

Start to use gpiod API for reset gpio.

Signed-off-by Jyri Sarha <[email protected]>

---
 drivers/video/fbdev/ssd1307fb.c | 25 ++++++++-----------------
 1 file changed, 8 insertions(+), 17 deletions(-)

drivers/video/fbdev/ssd1307fb.c +8 ~~-17~~

index 2925d5c..8ffaaee 100644
@@ -73,7 +73,7 @@ struct ssd1307fb_par {
 	u32 prechargep2;
 	struct pwm_device *pwm;
 	u32 pwm_period;
-	int reset;
+	struct gpio_desc *reset;
 	u32 seg_remap;
 	u32 vcomh;
 	u32 width;

@@ -561,10 +561,11 @@ static int ssd1307fb_probe(struct i2c_client *client,
 
 	par->device_info = of_device_get_match_data(&client->dev);
 
-	par->reset = of_get_named_gpio(client->dev.of_node,
-					 "reset-gpios", 0);
-	if (!gpio_is_valid(par->reset)) {
-		ret = -EINVAL;
+	par->reset = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_LOW);
+	if (IS_ERR(par->reset)) {
+		dev_err(&client->dev, "failed to get reset gpio: %ld\n",
+			PTR_ERR(par->reset));
+		ret = PTR_ERR(par->reset);
 		goto fb_alloc_error;
 	}

@@ -642,22 +643,12 @@ static int ssd1307fb_probe(struct i2c_client *client,
 
 	fb_deferred_io_init(info);
 
-	ret = devm_gpio_request_one(&client->dev, par->reset,
-				    GPIOF_OUT_INIT_HIGH,
-				    "oled-reset");
-	if (ret) {
-		dev_err(&client->dev,
-			"failed to request gpio %d: %d\n",
-			par->reset, ret);
-		goto reset_oled_error;
-	}
-
 	i2c_set_clientdata(client, info);
 
 	/* Reset the screen */
-	gpio_set_value(par->reset, 0);
+	gpiod_set_value(par->reset, 0);
 	udelay(4);
-	gpio_set_value(par->reset, 1);
+	gpiod_set_value(par->reset, 1);
 	udelay(4);
 
 	ret = ssd1307fb_init(par);

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Jyri Sarha

author

2017-01-13 10:35 UTC #3 lore raw

PATCH v2 2/5 fbdev: ssd1307fb: Remove reset-active-low from the DT binding document

In reply to a message not in the archive

Remove reset-active-low from the devicetree binding document. The actual implementation has never been there in the driver code and there is no reason to add it because the gpiod API supports gpio flags, including GPIO_ACTIVE_LOW, directly trough its own devicetree binding.

Signed-off-by Jyri Sarha <[email protected]>

---
 Documentation/devicetree/bindings/display/ssd1307fb.txt | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Documentation/devicetree/bindings/display/ssd1307fb.txt +2 -2

index eb31ed4..4aee67f 100644
@@ -8,14 +8,14 @@ Required properties:
          0x3c or 0x3d
   - pwm: Should contain the pwm to use according to the OF device tree PWM
          specification [0]. Only required for the ssd1307.
-  - reset-gpios: Should contain the GPIO used to reset the OLED display
+  - reset-gpios: Should contain the GPIO used to reset the OLED display. See
+                 Documentation/devicetree/bindings/gpio/gpio.txt for details.
   - solomon,height: Height in pixel of the screen driven by the controller
   - solomon,width: Width in pixel of the screen driven by the controller
   - solomon,page-offset: Offset of pages (band of 8 pixels) that the screen is
     mapped to.
 
 Optional properties:
-  - reset-active-low: Is the reset gpio is active on physical low?
   - solomon,segment-no-remap: Display needs normal (non-inverted) data column
                               to segment mapping
   - solomon,com-seq: Display uses sequential COM pin configuration

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Rob Herring

2017-01-18 22:28 UTC #5 lore raw

Re: [PATCH v2 2/5] fbdev: ssd1307fb: Remove reset-active-low from the DT binding document

Quoted 15 lines · Jyri Sarha

Remove reset-active-low from the devicetree binding document. The actual implementation has never been there in the driver code and there is no reason to add it because the gpiod API supports gpio flags, including GPIO_ACTIVE_LOW, directly trough its own devicetree binding.
Signed-off-by Jyri Sarha <[email protected]>
---
 Documentation/devicetree/bindings/display/ssd1307fb.txt | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
Documentation/devicetree/bindings/display/ssd1307fb.txt +0 -0
index eb31ed4..4aee67f 100644

Documentation/devicetree/bindings/display/ssd1307fb.txt Required properties: · line 12

Quoted 6 lines

Documentation/devicetree/bindings/display/ssd1307fb.txt +2 -1

@@ -8,14 +8,14 @@ Required properties:
          0x3c or 0x3d
   - pwm: Should contain the pwm to use according to the OF device tree PWM
          specification [0]. Only required for the ssd1307.
-  - reset-gpios: Should contain the GPIO used to reset the OLED display
+  - reset-gpios: Should contain the GPIO used to reset the OLED display. See
+                 Documentation/devicetree/bindings/gpio/gpio.txt for details.

You need to define the active state. Does the active state actually vary? Sounds like the compatible is not specific enough unless some boards have an inverter.

Quoted 13 lines

Documentation/devicetree/bindings/display/ssd1307fb.txt +0 -1

   - solomon,height: Height in pixel of the screen driven by the controller
   - solomon,width: Width in pixel of the screen driven by the controller
   - solomon,page-offset: Offset of pages (band of 8 pixels) that the screen is
     mapped to.
 
 Optional properties:
-  - reset-active-low: Is the reset gpio is active on physical low?
   - solomon,segment-no-remap: Display needs normal (non-inverted) data column
                               to segment mapping
   - solomon,com-seq: Display uses sequential COM pin configuration

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Jyri Sarha

author

2017-01-19 08:24 UTC #6 lore raw

Re: [PATCH v2 2/5] fbdev: ssd1307fb: Remove reset-active-low from the DT binding document

Quoted 11 lines · Rob Herring

Quoted 10 lines · Jyri Sarha
Remove reset-active-low from the devicetree binding document. The actual implementation has never been there in the driver code and there is no reason to add it because the gpiod API supports gpio flags, including GPIO_ACTIVE_LOW, directly trough its own devicetree binding.
Signed-off-by Jyri Sarha <[email protected]>
---
 Documentation/devicetree/bindings/display/ssd1307fb.txt | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Quoted 15 lines

Documentation/devicetree/bindings/display/ssd1307fb.txt Required properties: · line 12
Quoted 11 lines
Documentation/devicetree/bindings/display/ssd1307fb.txt +2 -1
index eb31ed4..4aee67f 100644
@@ -8,14 +8,14 @@ Required properties:
          0x3c or 0x3d
   - pwm: Should contain the pwm to use according to the OF device tree PWM
          specification [0]. Only required for the ssd1307.
-  - reset-gpios: Should contain the GPIO used to reset the OLED display
+  - reset-gpios: Should contain the GPIO used to reset the OLED display. See
+                 Documentation/devicetree/bindings/gpio/gpio.txt for details.
You need to define the active state. Does the active state actually vary? Sounds like the compatible is not specific enough unless some boards have an inverter.

No, I am not aware of the active state ever varying. For some reason someone specified the reset-active-low, but probably in the end it was not needed after all because the implementation was not added.

The only reason I can think of why the reset gpio would need active low flag is very weird board design or broken gpio driver.

Best regards,
Jyri
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Jyri Sarha

author

2017-01-13 10:35 UTC #7 lore raw

PATCH v2 3/5 fbdev: ssd1307fb: Make reset gpio devicetree property optional

In reply to a message not in the archive

Make reset gpio devicetree property optional. Depending on the board designing there may not be a dedicated gpio for resetting the display. Without a proper reset there may be some junk in the display memory at probe time, so in such a case the display memory is cleared before turning it on. The devicetree binding document is also updated.

Signed-off-by Jyri Sarha <[email protected]>

---
 .../devicetree/bindings/display/ssd1307fb.txt         |  4 ++--
 drivers/video/fbdev/ssd1307fb.c                       | 19 +++++++++++++------
 2 files changed, 15 insertions(+), 8 deletions(-)

Documentation/devicetree/bindings/display/ssd1307fb.txt +2 -2

index 4aee67f..6617df6 100644
@@ -8,14 +8,14 @@ Required properties:
          0x3c or 0x3d
   - pwm: Should contain the pwm to use according to the OF device tree PWM
          specification [0]. Only required for the ssd1307.
-  - reset-gpios: Should contain the GPIO used to reset the OLED display. See
-                 Documentation/devicetree/bindings/gpio/gpio.txt for details.
   - solomon,height: Height in pixel of the screen driven by the controller
   - solomon,width: Width in pixel of the screen driven by the controller
   - solomon,page-offset: Offset of pages (band of 8 pixels) that the screen is
     mapped to.
 
 Optional properties:
+  - reset-gpios: The GPIO used to reset the OLED display, if available. See
+                 Documentation/devicetree/bindings/gpio/gpio.txt for details.
   - solomon,segment-no-remap: Display needs normal (non-inverted) data column
                               to segment mapping
   - solomon,com-seq: Display uses sequential COM pin configuration

drivers/video/fbdev/ssd1307fb.c +13 -6

index 8ffaaee..89372af 100644
@@ -439,6 +439,10 @@ static int ssd1307fb_init(struct ssd1307fb_par *par)
 	if (ret < 0)
 		return ret;
 
+	/* Clear the screen if we could not give reset at probe time */
+	if (!par->reset)
+		ssd1307fb_update_display(par);
+
 	/* Turn on the display */
 	ret = ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_ON);
 	if (ret < 0)

@@ -561,7 +565,8 @@ static int ssd1307fb_probe(struct i2c_client *client,
 
 	par->device_info = of_device_get_match_data(&client->dev);
 
-	par->reset = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_LOW);
+	par->reset = devm_gpiod_get_optional(&client->dev, "reset",
+					     GPIOD_OUT_LOW);
 	if (IS_ERR(par->reset)) {
 		dev_err(&client->dev, "failed to get reset gpio: %ld\n",
 			PTR_ERR(par->reset));

@@ -645,11 +650,13 @@ static int ssd1307fb_probe(struct i2c_client *client,
 
 	i2c_set_clientdata(client, info);
 
-	/* Reset the screen */
-	gpiod_set_value(par->reset, 0);
-	udelay(4);
-	gpiod_set_value(par->reset, 1);
-	udelay(4);
+	if (par->reset) {
+		/* Reset the screen */
+		gpiod_set_value(par->reset, 0);
+		udelay(4);
+		gpiod_set_value(par->reset, 1);
+		udelay(4);
+	}
 
 	ret = ssd1307fb_init(par);
 	if (ret)

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Jyri Sarha

author

2017-01-13 10:35 UTC #8 lore raw

PATCH v2 4/5 fbdev/ssd1307fb: add support to enable VBAT

In reply to a message not in the archive

From: Tomi Valkeinen <[email protected]>

SSD1306 needs VBAT when it is wired in charge pump configuration. This patch adds support to the driver to enable VBAT regulator at init time.

Signed-off-by Tomi Valkeinen <[email protected]>

Reviewed-by Roger Quadros <[email protected]>

Signed-off-by Jyri Sarha <[email protected]>

---
 .../devicetree/bindings/display/ssd1307fb.txt        |  1 +
 drivers/video/fbdev/ssd1307fb.c                      | 20 +++++++++++++++++++-
 2 files changed, 20 insertions(+), 1 deletion(-)

Documentation/devicetree/bindings/display/ssd1307fb.txt +1 -0

index 6617df6..209d931 100644
@@ -16,6 +16,7 @@ Required properties:
 Optional properties:
   - reset-gpios: The GPIO used to reset the OLED display, if available. See
                  Documentation/devicetree/bindings/gpio/gpio.txt for details.
+  - vbat-supply: The supply for VBAT
   - solomon,segment-no-remap: Display needs normal (non-inverted) data column
                               to segment mapping
   - solomon,com-seq: Display uses sequential COM pin configuration

drivers/video/fbdev/ssd1307fb.c +19 -1

index 89372af..616a6a3 100644
@@ -16,6 +16,7 @@
 #include <linux/of_gpio.h>
 #include <linux/pwm.h>
 #include <linux/uaccess.h>
+#include <linux/regulator/consumer.h>
 
 #define SSD1307FB_DATA			0x40
 #define SSD1307FB_COMMAND		0x80

@@ -74,6 +75,7 @@ struct ssd1307fb_par {
 	struct pwm_device *pwm;
 	u32 pwm_period;
 	struct gpio_desc *reset;
+	struct regulator *vbat_reg;
 	u32 seg_remap;
 	u32 vcomh;
 	u32 width;

@@ -574,6 +576,14 @@ static int ssd1307fb_probe(struct i2c_client *client,
 		goto fb_alloc_error;
 	}
 
+	par->vbat_reg = devm_regulator_get_optional(&client->dev, "vbat");
+	if (IS_ERR(par->vbat_reg)) {
+		dev_err(&client->dev, "failed to get VBAT regulator: %ld\n",
+			PTR_ERR(par->vbat_reg));
+		ret = PTR_ERR(par->vbat_reg);
+		goto fb_alloc_error;
+	}
+
 	if (of_property_read_u32(node, "solomon,width", &par->width))
 		par->width = 96;

@@ -658,9 +668,15 @@ static int ssd1307fb_probe(struct i2c_client *client,
 		udelay(4);
 	}
 
+	ret = regulator_enable(par->vbat_reg);
+	if (ret) {
+		dev_err(&client->dev, "failed to enable VBAT: %d\n", ret);
+		goto reset_oled_error;
+	}
+
 	ret = ssd1307fb_init(par);
 	if (ret)
-		goto reset_oled_error;
+		goto regulator_enable_error;
 
 	ret = register_framebuffer(info);
 	if (ret) {

@@ -693,6 +709,8 @@ static int ssd1307fb_probe(struct i2c_client *client,
 		pwm_disable(par->pwm);
 		pwm_put(par->pwm);
 	};
+regulator_enable_error:
+	regulator_disable(par->vbat_reg);
 reset_oled_error:
 	fb_deferred_io_cleanup(info);
 fb_alloc_error:

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Rob Herring

2017-01-18 22:33 UTC #10 lore raw

Re: [PATCH v2 4/5] fbdev/ssd1307fb: add support to enable VBAT

Quoted 18 lines · Jyri Sarha

From: Tomi Valkeinen <[email protected]>
SSD1306 needs VBAT when it is wired in charge pump configuration. This patch adds support to the driver to enable VBAT regulator at init time.
Signed-off-by Tomi Valkeinen <[email protected]>
Reviewed-by Roger Quadros <[email protected]>
Signed-off-by Jyri Sarha <[email protected]>
---
 .../devicetree/bindings/display/ssd1307fb.txt        |  1 +
 drivers/video/fbdev/ssd1307fb.c                      | 20 +++++++++++++++++++-
 2 files changed, 20 insertions(+), 1 deletion(-)
Documentation/devicetree/bindings/display/ssd1307fb.txt +0 -0
index 6617df6..209d931 100644

Documentation/devicetree/bindings/display/ssd1307fb.txt Required properties: · line 19

Quoted 4 lines

Documentation/devicetree/bindings/display/ssd1307fb.txt +1 -0

@@ -16,6 +16,7 @@ Required properties:
 Optional properties:
   - reset-gpios: The GPIO used to reset the OLED display, if available. See
                  Documentation/devicetree/bindings/gpio/gpio.txt for details.
+  - vbat-supply: The supply for VBAT

According to the datasheet, SSD1307 has 2 supplies: Vdd and Vcc

I don't see any mention of a charge pump, so that must be an external component.

Documentation/devicetree/bindings/display/ssd1307fb.txt Required properties: · line 22

Quoted 3 lines

Documentation/devicetree/bindings/display/ssd1307fb.txt +0 -0

   - solomon,segment-no-remap: Display needs normal (non-inverted) data column
                               to segment mapping
   - solomon,com-seq: Display uses sequential COM pin configuration

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Tomi Valkeinen

2017-01-19 13:15 UTC #11 lore raw

Re: [PATCH v2 4/5] fbdev/ssd1307fb: add support to enable VBAT

Quoted 26 lines · Rob Herring

Quoted 18 lines · Jyri Sarha
From: Tomi Valkeinen <[email protected]>
SSD1306 needs VBAT when it is wired in charge pump configuration. This patch adds support to the driver to enable VBAT regulator at init time.
Signed-off-by Tomi Valkeinen <[email protected]>
Reviewed-by Roger Quadros <[email protected]>
Signed-off-by Jyri Sarha <[email protected]>
---
 .../devicetree/bindings/display/ssd1307fb.txt        |  1 +
 drivers/video/fbdev/ssd1307fb.c                      | 20 +++++++++++++++++++-
 2 files changed, 20 insertions(+), 1 deletion(-)
Documentation/devicetree/bindings/display/ssd1307fb.txt +0 -0
index 6617df6..209d931 100644
Documentation/devicetree/bindings/display/ssd1307fb.txt Required properties: · line 19
Quoted 4 lines
Documentation/devicetree/bindings/display/ssd1307fb.txt +1 -0
@@ -16,6 +16,7 @@ Required properties:
 Optional properties:
   - reset-gpios: The GPIO used to reset the OLED display, if available. See
                  Documentation/devicetree/bindings/gpio/gpio.txt for details.
+  - vbat-supply: The supply for VBAT
According to the datasheet, SSD1307 has 2 supplies: Vdd and Vcc

Quoted 2 lines

I don't see any mention of a charge pump, so that must be an external component.

VBAT is for SSD1306. Perhaps the DT doc should mention it.

Tomi

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Rob Herring

2017-01-19 15:03 UTC #13 lore raw

Re: [PATCH v2 4/5] fbdev/ssd1307fb: add support to enable VBAT

Quoted 27 lines · Tomi Valkeinen

Quoted 26 lines · Rob Herring
Quoted 18 lines · Jyri Sarha
From: Tomi Valkeinen <[email protected]>
SSD1306 needs VBAT when it is wired in charge pump configuration. This patch adds support to the driver to enable VBAT regulator at init time.
Signed-off-by Tomi Valkeinen <[email protected]>
Reviewed-by Roger Quadros <[email protected]>
Signed-off-by Jyri Sarha <[email protected]>
---
 .../devicetree/bindings/display/ssd1307fb.txt        |  1 +
 drivers/video/fbdev/ssd1307fb.c                      | 20 +++++++++++++++++++-
 2 files changed, 20 insertions(+), 1 deletion(-)
Documentation/devicetree/bindings/display/ssd1307fb.txt +0 -0
index 6617df6..209d931 100644
Documentation/devicetree/bindings/display/ssd1307fb.txt Required properties: · line 19
Quoted 4 lines
Documentation/devicetree/bindings/display/ssd1307fb.txt +1 -0
@@ -16,6 +16,7 @@ Required properties:
 Optional properties:
   - reset-gpios: The GPIO used to reset the OLED display, if available. See
                  Documentation/devicetree/bindings/gpio/gpio.txt for details.
+  - vbat-supply: The supply for VBAT
According to the datasheet, SSD1307 has 2 supplies: Vdd and Vcc

Quoted 4 lines

Quoted 2 lines
I don't see any mention of a charge pump, so that must be an external component.
VBAT is for SSD1306. Perhaps the DT doc should mention it.

Datasheet says VBAT is reserved, connect to Vdd. I would just describe Vdd and Vcc in that case.

Rob
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Tomi Valkeinen

2017-01-19 15:08 UTC #15 lore raw

Re: [PATCH v2 4/5] fbdev/ssd1307fb: add support to enable VBAT

Quoted 9 lines · Rob Herring

Quoted 6 lines
Quoted 4 lines
According to the datasheet, SSD1307 has 2 supplies: Vdd and Vcc
I don't see any mention of a charge pump, so that must be an external component.
VBAT is for SSD1306. Perhaps the DT doc should mention it.
Datasheet says VBAT is reserved, connect to Vdd. I would just describe Vdd and Vcc in that case.

I'm no HW guy, but as far as I understand, you can wire it up two ways. One has VBAT connected to VDD. The other one has VBAT connected to external supply. See "Figure 1 : Application Example of SSD1306Z with charge bump".

Tomi

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Rob Herring

2017-01-19 16:22 UTC #17 lore raw

Re: [PATCH v2 4/5] fbdev/ssd1307fb: add support to enable VBAT

Quoted 9 lines · Tomi Valkeinen

Quoted 7 lines · Rob Herring
Quoted 6 lines
Quoted 4 lines
According to the datasheet, SSD1307 has 2 supplies: Vdd and Vcc
I don't see any mention of a charge pump, so that must be an external component.
VBAT is for SSD1306. Perhaps the DT doc should mention it.

Quoted 7 lines

Quoted 2 lines
Datasheet says VBAT is reserved, connect to Vdd. I would just describe Vdd and Vcc in that case.
I'm no HW guy, but as far as I understand, you can wire it up two ways. One has VBAT connected to VDD. The other one has VBAT connected to external supply. See "Figure 1 : Application Example of SSD1306Z with charge bump".

I should have kept reading...

So either Vdd and Vbat supplies or Vdd and Vcc supplies are valid and the former only applies to 1306.

Rob
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Jyri Sarha

author

2017-01-13 10:35 UTC #18 lore raw

PATCH v2 5/5 fbdev/ssd1307fb: clear screen in probe

In reply to a message not in the archive

From: Tomi Valkeinen <[email protected]>

SSD1306 does not clear the panel's framebuffer automatically, even if a HW reset happens, so we need to do that at probe time before enabling the panel.

Signed-off-by Tomi Valkeinen <[email protected]>

Signed-off-by Jyri Sarha <[email protected]>

---
 drivers/video/fbdev/ssd1307fb.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

drivers/video/fbdev/ssd1307fb.c +2 -3

index 616a6a3..5c87ae4 100644
@@ -441,9 +441,8 @@ static int ssd1307fb_init(struct ssd1307fb_par *par)
 	if (ret < 0)
 		return ret;
 
-	/* Clear the screen if we could not give reset at probe time */
-	if (!par->reset)
-		ssd1307fb_update_display(par);
+	/* Clear the screen */
+	ssd1307fb_update_display(par);
 
 	/* Turn on the display */
 	ret = ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_ON);

Signature · 6 lines

1.9.1

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Bartlomiej Zolnierkiewicz

2017-02-08 15:15 UTC #19 lore raw

In reply to a message not in the archive

Hi,

Quoted 21 lines · Jyri Sarha

Changes since first version:
- Cherry-picked "fbdev/ssd1307fb: add support to enable VBAT" again beacuse of weird mixup in the first version
- Also tested the code on top of v4.10-rc3 with am335x-icev2 evm
We needed these changes for couple of our evm. Some of these patches have been on mainline list before, but after that forgotten. Now we are forward porting these on for out internal release, so this is a good time to get them to mainline too.
Everything else is quite straight forward, but removing the reset-active-low dts property is a questionable at least in theory. However, in practice if anyone was using the property in their device-tree blobs, they have never been able to get desired effect with mainline kernel.
Jyri Sarha (3):
fbdev: ssd1307fb: Start to use gpiod API for reset gpio
fbdev: ssd1307fb: Remove reset-active-low from the DT binding document
fbdev: ssd1307fb: Make reset gpio devicetree property optional

Quoted 7 lines

Tomi Valkeinen (2):
fbdev/ssd1307fb: add support to enable VBAT
fbdev/ssd1307fb: clear screen in probe
 .../devicetree/bindings/display/ssd1307fb.txt      |  5 +-
 drivers/video/fbdev/ssd1307fb.c                    | 55 ++++++++++++++--------
 2 files changed, 38 insertions(+), 22 deletions(-)

Patchset queued for 4.11, thanks.

Best regards,
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Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

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