diff mbox

[1/2] video: fbdev: imxfb: support AUS mode

Message ID 1488193030-13064-1-git-send-email-martin@kaiser.cx (mailing list archive)
State New, archived
Headers show

Commit Message

Martin Kaiser Feb. 27, 2017, 10:56 a.m. UTC
Some displays require setting AUS mode in the LDCD AUS Mode Control
Register to work with the imxfb driver. Like the value of the Panel
Configuration Register, the AUS Mode Control Register's value depends on
the display mode.

Allow setting this register from the device tree. Make the device tree
node optional to keep the DT ABI stable. This register is available only
on imx21 and compatible chipsets.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
---
 drivers/video/fbdev/imxfb.c               | 19 +++++++++++++++++++
 include/linux/platform_data/video-imxfb.h |  1 +
 2 files changed, 20 insertions(+)

Comments

Uwe Kleine-König Feb. 27, 2017, 8:36 p.m. UTC | #1
Hello,

given fbdev is orphaned
(http://git.kernel.org/linus/238600783d7470bec19350b0ee79e01825d3c84f)
I think it would be nice to move the imxfb driver over to drm.
I don't know much about drm, so I cannot say if that is easy or not, but
long term I think this is more robust than fbdev.

Best regards
Uwe
Martin Kaiser Feb. 27, 2017, 10:33 p.m. UTC | #2
Hello Uwe,

Thus wrote Uwe Kleine-König (u.kleine-koenig@pengutronix.de):

> given fbdev is orphaned
> (http://git.kernel.org/linus/238600783d7470bec19350b0ee79e01825d3c84f)

fbdev is no longer orphaned, Bartlomiej is the new maintainer.

> I think it would be nice to move the imxfb driver over to drm.
> I don't know much about drm, so I cannot say if that is easy or not, but
> long term I think this is more robust than fbdev.

I am aware that fbdev is in maintenance mode. However, I hope that small
modifications like the one I submitted are still possible.

In the long run, I agree that we should move imxfb to drm.

Best regards,
Martin
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Bartlomiej Zolnierkiewicz Feb. 28, 2017, 11:45 a.m. UTC | #3
Hi,

On Monday, February 27, 2017 11:33:36 PM Martin Kaiser wrote:
> Hello Uwe,
> 
> Thus wrote Uwe Kleine-König (u.kleine-koenig@pengutronix.de):
> 
> > given fbdev is orphaned
> > (http://git.kernel.org/linus/238600783d7470bec19350b0ee79e01825d3c84f)
> 
> fbdev is no longer orphaned, Bartlomiej is the new maintainer.
> 
> > I think it would be nice to move the imxfb driver over to drm.
> > I don't know much about drm, so I cannot say if that is easy or not, but
> > long term I think this is more robust than fbdev.
> 
> I am aware that fbdev is in maintenance mode. However, I hope that small
> modifications like the one I submitted are still possible.

Yes, such changes are fine.

BTW Please merge both patches into one or at least make Cc:
list complete so people can see the whole context easily
(i.e. I didn't get patch #2 in my patches folder and Rob
didn't get patch #1).

> In the long run, I agree that we should move imxfb to drm.
> 
> Best regards,
> Martin

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

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diff mbox

Patch

diff --git a/drivers/video/fbdev/imxfb.c b/drivers/video/fbdev/imxfb.c
index 1b0faad..a05cad4 100644
--- a/drivers/video/fbdev/imxfb.c
+++ b/drivers/video/fbdev/imxfb.c
@@ -117,6 +117,8 @@ 
 
 #define IMXFB_LSCR1_DEFAULT 0x00120300
 
+#define LCDC_LAUSCR	0x80
+
 /* Used fb-mode. Can be set on kernel command line, therefore file-static. */
 static const char *fb_mode;
 
@@ -158,6 +160,7 @@  struct imxfb_info {
 	dma_addr_t		dbar2;
 
 	u_int			pcr;
+	u_int			lauscr;
 	u_int			pwmr;
 	u_int			lscr1;
 	u_int			dmacr;
@@ -422,6 +425,11 @@  static int imxfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
 	pcr |= imxfb_mode->pcr & ~(0x3f | (7 << 25));
 
 	fbi->pcr = pcr;
+	/*
+	 * The LCDC AUS Mode Control Register does not exist on imx1.
+	 */
+	if (!is_imx1_fb(fbi))
+		fbi->lauscr = imxfb_mode->lauscr;
 
 	/*
 	 * Copy the RGB parameters for this display
@@ -638,6 +646,9 @@  static int imxfb_activate_var(struct fb_var_screeninfo *var, struct fb_info *inf
 	if (fbi->dmacr)
 		writel(fbi->dmacr, fbi->regs + LCDC_DMACR);
 
+	if (fbi->lauscr)
+		writel(fbi->lauscr, fbi->regs + LCDC_LAUSCR);
+
 	return 0;
 }
 
@@ -707,6 +718,7 @@  static int imxfb_of_read_mode(struct device *dev, struct device_node *np,
 	struct fb_videomode *of_mode = &imxfb_mode->mode;
 	u32 bpp;
 	u32 pcr;
+	u32 lauscr;
 
 	ret = of_property_read_string(np, "model", &of_mode->name);
 	if (ret)
@@ -734,6 +746,13 @@  static int imxfb_of_read_mode(struct device *dev, struct device_node *np,
 	imxfb_mode->bpp = bpp;
 	imxfb_mode->pcr = pcr;
 
+	/*
+	 * fsl,lauscr is optional
+	 */
+	ret = of_property_read_u32(np, "fsl,lauscr", &lauscr);
+	if (ret == 0)
+		imxfb_mode->lauscr = lauscr;
+
 	return 0;
 }
 
diff --git a/include/linux/platform_data/video-imxfb.h b/include/linux/platform_data/video-imxfb.h
index a5c0a71..fdd2d4c 100644
--- a/include/linux/platform_data/video-imxfb.h
+++ b/include/linux/platform_data/video-imxfb.h
@@ -50,6 +50,7 @@ 
 struct imx_fb_videomode {
 	struct fb_videomode mode;
 	u32 pcr;
+	u32 lauscr;
 	unsigned char	bpp;
 };