[PATCH v5 00/12] video: da8xx-fb: am335x DT support

[PATCH v5 00/12] video: da8xx-fb: am335x DT support

[Afzal Mohammed]

Hi,

This series adds DT support to da8xx-fb driver (device found on
DaVinci and AM335x SoC's). It does certain cleanup's in the process.

This series as compared to previous version goes back to v2 way of
configuring pixel clock rate. i.e. set divider if rate is within
the range that is configurable with existing input clock rate, else
change input clock rate as required instead of modeling CCF clock
nodes in the driver (more details in 12/12)

This makes use of Steffen Trumtrar's v17 of display timing DT support.

Testing has been done on AM335x SoC based boards like AM335x EVM. It
has also been verified that display on DA850 EVM (non-DT boot) works
as earlier.

This series is based on v3.8-rc3,
 and is dependent on,
1. Series v17 "of: add display helper" by,
        Steffen Trumtrar <s.trumtrar@pengutronix.de>
2. Patch "da8xx: Allow use by am33xx based devices" by,
        Pantelis Antoniou <panto@antoniou-consulting.com>
3. Series v3 "video: da8xx-fb: runtime timing configuration" by,
        me (Afzal Mohammed <afzal@ti.com>)

To test this series on AM335x based boards,
1. Series "HWMOD fixes for AM33xx PWM submodules and device tree nodes" by,
        Philip, Avinash <avinashphilip@ti.com>
as well as following,
2. Series v2 "ARM: dts: AM33XX: lcdc support",
3. Patch v2 "ARM: OMAP2+: dpll: am335x - avoid freqsel",
4. Patch v2 "ARM: OMAP2+: clock: DEFINE_STRUCT_CLK_FLAGS helper",
5. Patch v2 "ARM: AM33XX: clock: SET_RATE_PARENT in lcd path" by,
	me (Afzal Mohammed <afzal@ti.com>)
would be needed.

All above dependencies along with those required for testing is available
@ git://gitorious.org/x0148406-public/linux-kernel.git tags/da8xx-fb-dt-v5

Regards
Afzal

v5: use v2 method of configuring pixel clock rate instead of modeling
    CCF clock nodes in driver, i.e. set divider if rate is within
    the range that is configurable with existing input clock rate,
    else change input clock rate as required.
v4: use new registration for clock divider having minimum divider
    requirement and have ifdef'ery in a better way
v3: model CCF clock divider with parent propogation if CCF selected
v2: 2 new patches - one to configure clock rate properly (12/12)and
    other to make io operations safe (1/12)



Afzal Mohammed (11):
  video: da8xx-fb: make io operations safe
  video: da8xx-fb: enable sync lost intr for v2 ip
  video: da8xx-fb: use devres
  video: da8xx-fb: ensure non-null cfg in pdata
  video: da8xx-fb: reorganize panel detection
  video: da8xx-fb: minimal dt support
  video: da8xx-fb: invoke platform callback safely
  video: da8xx-fb: obtain fb_videomode info from dt
  video: da8xx-fb: ensure pdata only for non-dt
  video: da8xx-fb: setup struct lcd_ctrl_config for dt
  video: da8xx-fb: set upstream clock rate (if reqd)

Manjunathappa, Prakash (1):
  video: da8xx-fb: fix 24bpp raster configuration

 .../devicetree/bindings/video/fb-da8xx.txt         |  37 ++++
 drivers/video/da8xx-fb.c                           | 226 ++++++++++++++-------
 2 files changed, 194 insertions(+), 69 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/video/fb-da8xx.txt

-- 
1.7.12

[PATCH v5 01/12] video: da8xx-fb: make io operations safe

[Afzal Mohammed]

Replace __raw_readl/__raw_writel with readl/writel; this driver is
reused on ARMv7 (AM335x SoC).

Signed-off-by: Afzal Mohammed <afzal@ti.com>
---

v2: new patch

 drivers/video/da8xx-fb.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/video/da8xx-fb.c b/drivers/video/da8xx-fb.c
index 720604c..35a33ca 100644
--- a/drivers/video/da8xx-fb.c
+++ b/drivers/video/da8xx-fb.c
@@ -141,12 +141,12 @@ static int frame_done_flag;
 
 static inline unsigned int lcdc_read(unsigned int addr)
 {
-	return (unsigned int)__raw_readl(da8xx_fb_reg_base + (addr));
+	return (unsigned int)readl(da8xx_fb_reg_base + (addr));
 }
 
 static inline void lcdc_write(unsigned int val, unsigned int addr)
 {
-	__raw_writel(val, da8xx_fb_reg_base + (addr));
+	writel(val, da8xx_fb_reg_base + (addr));
 }
 
 struct da8xx_fb_par {
-- 
1.7.12

[PATCH v5 02/12] video: da8xx-fb: fix 24bpp raster configuration

[Afzal Mohammed]

From: "Manjunathappa, Prakash" <prakash.pm@ti.com>

Set only LCD_V2_TFT_24BPP_MODE bit for 24bpp and LCD_V2_TFT_24BPP_UNPACK
bit along with LCD_V2_TFT_24BPP_MODE for 32bpp configuration.

Patch is tested on am335x-evm for 24bpp and da850-evm for 16bpp
configurations.

Signed-off-by: Manjunathappa, Prakash <prakash.pm@ti.com>
Signed-off-by: Afzal Mohammed <afzal@ti.com>
---
 drivers/video/da8xx-fb.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/video/da8xx-fb.c b/drivers/video/da8xx-fb.c
index 35a33ca..7f92f37 100644
--- a/drivers/video/da8xx-fb.c
+++ b/drivers/video/da8xx-fb.c
@@ -550,10 +550,10 @@ static int lcd_cfg_frame_buffer(struct da8xx_fb_par *par, u32 width, u32 height,
 	case 4:
 	case 16:
 		break;
-	case 24:
-		reg |= LCD_V2_TFT_24BPP_MODE;
 	case 32:
 		reg |= LCD_V2_TFT_24BPP_UNPACK;
+	case 24:
+		reg |= LCD_V2_TFT_24BPP_MODE;
 		break;
 
 	case 8:
-- 
1.7.12

[PATCH v5 03/12] video: da8xx-fb: enable sync lost intr for v2 ip

[Afzal Mohammed]

interrupt handler is checking for sync lost interrupt, but it was not
enabled, enable it.

Signed-off-by: Afzal Mohammed <afzal@ti.com>
---
 drivers/video/da8xx-fb.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/video/da8xx-fb.c b/drivers/video/da8xx-fb.c
index 7f92f37..ca69e01 100644
--- a/drivers/video/da8xx-fb.c
+++ b/drivers/video/da8xx-fb.c
@@ -318,7 +318,7 @@ static void lcd_blit(int load_mode, struct da8xx_fb_par *par)
 			reg_int = lcdc_read(LCD_INT_ENABLE_SET_REG) |
 				LCD_V2_END_OF_FRAME0_INT_ENA |
 				LCD_V2_END_OF_FRAME1_INT_ENA |
-				LCD_FRAME_DONE;
+				LCD_FRAME_DONE | LCD_SYNC_LOST;
 			lcdc_write(reg_int, LCD_INT_ENABLE_SET_REG);
 		}
 		reg_dma |= LCD_DUAL_FRAME_BUFFER_ENABLE;
-- 
1.7.12

[PATCH v5 04/12] video: da8xx-fb: use devres

[Afzal Mohammed]

Replace existing resource handling in the driver with managed device
resource.

Signed-off-by: Afzal Mohammed <afzal@ti.com>
---
 drivers/video/da8xx-fb.c | 35 ++++++-----------------------------
 1 file changed, 6 insertions(+), 29 deletions(-)

diff --git a/drivers/video/da8xx-fb.c b/drivers/video/da8xx-fb.c
index ca69e01..7a32e83 100644
--- a/drivers/video/da8xx-fb.c
+++ b/drivers/video/da8xx-fb.c
@@ -1036,12 +1036,9 @@ static int fb_remove(struct platform_device *dev)
 				  par->p_palette_base);
 		dma_free_coherent(NULL, par->vram_size, par->vram_virt,
 				  par->vram_phys);
-		free_irq(par->irq, par);
 		pm_runtime_put_sync(&dev->dev);
 		pm_runtime_disable(&dev->dev);
 		framebuffer_release(info);
-		iounmap(da8xx_fb_reg_base);
-		release_mem_region(lcdc_regs->start, resource_size(lcdc_regs));
 
 	}
 	return 0;
@@ -1265,7 +1262,6 @@ static int fb_probe(struct platform_device *device)
 	struct fb_info *da8xx_fb_info;
 	struct clk *fb_clk = NULL;
 	struct da8xx_fb_par *par;
-	resource_size_t len;
 	int ret, i;
 	unsigned long ulcm;
 
@@ -1275,29 +1271,16 @@ static int fb_probe(struct platform_device *device)
 	}
 
 	lcdc_regs = platform_get_resource(device, IORESOURCE_MEM, 0);
-	if (!lcdc_regs) {
-		dev_err(&device->dev,
-			"Can not get memory resource for LCD controller\n");
-		return -ENOENT;
-	}
-
-	len = resource_size(lcdc_regs);
-
-	lcdc_regs = request_mem_region(lcdc_regs->start, len, lcdc_regs->name);
-	if (!lcdc_regs)
-		return -EBUSY;
-
-	da8xx_fb_reg_base = ioremap(lcdc_regs->start, len);
+	da8xx_fb_reg_base = devm_request_and_ioremap(&device->dev, lcdc_regs);
 	if (!da8xx_fb_reg_base) {
-		ret = -EBUSY;
-		goto err_request_mem;
+		dev_err(&device->dev, "memory resource setup failed\n");
+		return -EADDRNOTAVAIL;
 	}
 
-	fb_clk = clk_get(&device->dev, "fck");
+	fb_clk = devm_clk_get(&device->dev, "fck");
 	if (IS_ERR(fb_clk)) {
 		dev_err(&device->dev, "Can not get device clock\n");
-		ret = -ENODEV;
-		goto err_ioremap;
+		return -ENODEV;
 	}
 
 	pm_runtime_enable(&device->dev);
@@ -1458,7 +1441,7 @@ static int fb_probe(struct platform_device *device)
 		lcdc_irq_handler = lcdc_irq_handler_rev02;
 	}
 
-	ret = request_irq(par->irq, lcdc_irq_handler, 0,
+	ret = devm_request_irq(&device->dev, par->irq, lcdc_irq_handler, 0,
 			DRIVER_NAME, par);
 	if (ret)
 		goto irq_freq;
@@ -1488,12 +1471,6 @@ err_pm_runtime_disable:
 	pm_runtime_put_sync(&device->dev);
 	pm_runtime_disable(&device->dev);
 
-err_ioremap:
-	iounmap(da8xx_fb_reg_base);
-
-err_request_mem:
-	release_mem_region(lcdc_regs->start, len);
-
 	return ret;
 }
 
-- 
1.7.12

[PATCH v5 05/12] video: da8xx-fb: ensure non-null cfg in pdata

[Afzal Mohammed]

Ensure that platform data contains pointer for lcd_ctrl_config.

Signed-off-by: Afzal Mohammed <afzal@ti.com>
---
 drivers/video/da8xx-fb.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/video/da8xx-fb.c b/drivers/video/da8xx-fb.c
index 7a32e83..3b146bc 100644
--- a/drivers/video/da8xx-fb.c
+++ b/drivers/video/da8xx-fb.c
@@ -1320,6 +1320,11 @@ static int fb_probe(struct platform_device *device)
 
 	lcd_cfg = (struct lcd_ctrl_config *)fb_pdata->controller_data;
 
+	if (!lcd_cfg) {
+		ret = -EINVAL;
+		goto err_pm_runtime_disable;
+	}
+
 	da8xx_fb_info = framebuffer_alloc(sizeof(struct da8xx_fb_par),
 					&device->dev);
 	if (!da8xx_fb_info) {
-- 
1.7.12

[PATCH v5 06/12] video: da8xx-fb: reorganize panel detection

[Afzal Mohammed]

Move panel detection to a separate function, this helps in readability
as well as makes DT support cleaner.

Signed-off-by: Afzal Mohammed <afzal@ti.com>
---
 drivers/video/da8xx-fb.c | 42 ++++++++++++++++++++++++++----------------
 1 file changed, 26 insertions(+), 16 deletions(-)

diff --git a/drivers/video/da8xx-fb.c b/drivers/video/da8xx-fb.c
index 3b146bc..b6ea5e9 100644
--- a/drivers/video/da8xx-fb.c
+++ b/drivers/video/da8xx-fb.c
@@ -1253,6 +1253,27 @@ static struct fb_ops da8xx_fb_ops = {
 	.fb_blank = cfb_blank,
 };
 
+static struct fb_videomode *da8xx_fb_get_videomode(struct platform_device *dev)
+{
+	struct da8xx_lcdc_platform_data *fb_pdata = dev->dev.platform_data;
+	struct fb_videomode *lcdc_info;
+	int i;
+
+	for (i = 0, lcdc_info = known_lcd_panels;
+		i < ARRAY_SIZE(known_lcd_panels); i++, lcdc_info++) {
+		if (strcmp(fb_pdata->type, lcdc_info->name) = 0)
+			break;
+	}
+
+	if (i = ARRAY_SIZE(known_lcd_panels)) {
+		dev_err(&dev->dev, "no panel found\n");
+		return NULL;
+	}
+	dev_info(&dev->dev, "found %s panel\n", lcdc_info->name);
+
+	return lcdc_info;
+}
+
 static int fb_probe(struct platform_device *device)
 {
 	struct da8xx_lcdc_platform_data *fb_pdata @@ -1262,7 +1283,7 @@ static int fb_probe(struct platform_device *device)
 	struct fb_info *da8xx_fb_info;
 	struct clk *fb_clk = NULL;
 	struct da8xx_fb_par *par;
-	int ret, i;
+	int ret;
 	unsigned long ulcm;
 
 	if (fb_pdata = NULL) {
@@ -1270,6 +1291,10 @@ static int fb_probe(struct platform_device *device)
 		return -ENOENT;
 	}
 
+	lcdc_info = da8xx_fb_get_videomode(device);
+	if (lcdc_info = NULL)
+		return -ENODEV;
+
 	lcdc_regs = platform_get_resource(device, IORESOURCE_MEM, 0);
 	da8xx_fb_reg_base = devm_request_and_ioremap(&device->dev, lcdc_regs);
 	if (!da8xx_fb_reg_base) {
@@ -1303,21 +1328,6 @@ static int fb_probe(struct platform_device *device)
 		break;
 	}
 
-	for (i = 0, lcdc_info = known_lcd_panels;
-		i < ARRAY_SIZE(known_lcd_panels);
-		i++, lcdc_info++) {
-		if (strcmp(fb_pdata->type, lcdc_info->name) = 0)
-			break;
-	}
-
-	if (i = ARRAY_SIZE(known_lcd_panels)) {
-		dev_err(&device->dev, "GLCD: No valid panel found\n");
-		ret = -ENODEV;
-		goto err_pm_runtime_disable;
-	} else
-		dev_info(&device->dev, "GLCD: Found %s panel\n",
-					fb_pdata->type);
-
 	lcd_cfg = (struct lcd_ctrl_config *)fb_pdata->controller_data;
 
 	if (!lcd_cfg) {
-- 
1.7.12

[PATCH v5 07/12] video: da8xx-fb: minimal dt support

[Afzal Mohammed]

Driver is provided a means to have the probe triggered by DT.

Signed-off-by: Afzal Mohammed <afzal@ti.com>
---
 Documentation/devicetree/bindings/video/fb-da8xx.txt | 16 ++++++++++++++++
 drivers/video/da8xx-fb.c                             |  7 +++++++
 2 files changed, 23 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/video/fb-da8xx.txt

diff --git a/Documentation/devicetree/bindings/video/fb-da8xx.txt b/Documentation/devicetree/bindings/video/fb-da8xx.txt
new file mode 100644
index 0000000..581e014
--- /dev/null
+++ b/Documentation/devicetree/bindings/video/fb-da8xx.txt
@@ -0,0 +1,16 @@
+TI LCD Controller on DA830/DA850/AM335x SoC's
+
+Required properties:
+- compatible:
+	DA830 - "ti,da830-lcdc"
+	AM335x SoC's - "ti,am3352-lcdc", "ti,da830-lcdc"
+- reg: Address range of lcdc register set
+- interrupts: lcdc interrupt
+
+Example:
+
+lcdc@4830e000 {
+	compatible = "ti,am3352-lcdc", "ti,da830-lcdc";
+	reg =  <0x4830e000 0x1000>;
+	interrupts = <36>;
+};
diff --git a/drivers/video/da8xx-fb.c b/drivers/video/da8xx-fb.c
index b6ea5e9..08ee8eb 100644
--- a/drivers/video/da8xx-fb.c
+++ b/drivers/video/da8xx-fb.c
@@ -1595,6 +1595,12 @@ static int fb_resume(struct platform_device *dev)
 #define fb_resume NULL
 #endif
 
+static const struct of_device_id da8xx_fb_of_match[] = {
+	{.compatible = "ti,da830-lcdc", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, da8xx_fb_of_match);
+
 static struct platform_driver da8xx_fb_driver = {
 	.probe = fb_probe,
 	.remove = fb_remove,
@@ -1603,6 +1609,7 @@ static struct platform_driver da8xx_fb_driver = {
 	.driver = {
 		   .name = DRIVER_NAME,
 		   .owner = THIS_MODULE,
+		   .of_match_table = of_match_ptr(da8xx_fb_of_match),
 		   },
 };
 
-- 
1.7.12

[PATCH v5 08/12] video: da8xx-fb: invoke platform callback safely

[Afzal Mohammed]

Ensure that platform data is present before checking whether platform
callback is present (the one used to control backlight). So far this
was not an issue as driver was purely non-DT triggered, but now DT
support has been added.

Signed-off-by: Afzal Mohammed <afzal@ti.com>
---
 drivers/video/da8xx-fb.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/video/da8xx-fb.c b/drivers/video/da8xx-fb.c
index 08ee8eb..0beed20 100644
--- a/drivers/video/da8xx-fb.c
+++ b/drivers/video/da8xx-fb.c
@@ -1347,7 +1347,7 @@ static int fb_probe(struct platform_device *device)
 	par->dev = &device->dev;
 	par->lcdc_clk = fb_clk;
 	par->lcd_fck_rate = clk_get_rate(fb_clk);
-	if (fb_pdata->panel_power_ctrl) {
+	if (fb_pdata && fb_pdata->panel_power_ctrl) {
 		par->panel_power_ctrl = fb_pdata->panel_power_ctrl;
 		par->panel_power_ctrl(1);
 	}
-- 
1.7.12

[PATCH v5 09/12] video: da8xx-fb: obtain fb_videomode info from dt

[Afzal Mohammed]

Obtain fb_videomode details for the connected lcd panel using the
display timing details present in DT.

Signed-off-by: Afzal Mohammed <afzal@ti.com>
---
 .../devicetree/bindings/video/fb-da8xx.txt          | 21 +++++++++++++++++++++
 drivers/video/da8xx-fb.c                            | 17 +++++++++++++++++
 2 files changed, 38 insertions(+)

diff --git a/Documentation/devicetree/bindings/video/fb-da8xx.txt b/Documentation/devicetree/bindings/video/fb-da8xx.txt
index 581e014..0741f78 100644
--- a/Documentation/devicetree/bindings/video/fb-da8xx.txt
+++ b/Documentation/devicetree/bindings/video/fb-da8xx.txt
@@ -6,6 +6,12 @@ Required properties:
 	AM335x SoC's - "ti,am3352-lcdc", "ti,da830-lcdc"
 - reg: Address range of lcdc register set
 - interrupts: lcdc interrupt
+- display-timings: typical videomode of lcd panel, represented as child.
+  Refer Documentation/devicetree/bindings/video/display-timing.txt for
+  display timing binding details. If multiple videomodes are mentioned
+  in display timings node, typical videomode has to be mentioned as the
+  native mode or it has to be first child (driver cares only for native
+  videomode).
 
 Example:
 
@@ -13,4 +19,19 @@ lcdc@4830e000 {
 	compatible = "ti,am3352-lcdc", "ti,da830-lcdc";
 	reg =  <0x4830e000 0x1000>;
 	interrupts = <36>;
+	display-timings {
+		800x480p62 {
+			clock-frequency = <30000000>;
+			hactive = <800>;
+			vactive = <480>;
+			hfront-porch = <39>;
+			hback-porch = <39>;
+			hsync-len = <47>;
+			vback-porch = <29>;
+			vfront-porch = <13>;
+			vsync-len = <2>;
+			hsync-active = <1>;
+			vsync-active = <1>;
+		};
+	};
 };
diff --git a/drivers/video/da8xx-fb.c b/drivers/video/da8xx-fb.c
index 0beed20..0c68712 100644
--- a/drivers/video/da8xx-fb.c
+++ b/drivers/video/da8xx-fb.c
@@ -36,6 +36,7 @@
 #include <linux/slab.h>
 #include <linux/delay.h>
 #include <linux/lcm.h>
+#include <video/of_display_timing.h>
 #include <video/da8xx-fb.h>
 #include <asm/div64.h>
 
@@ -1257,8 +1258,24 @@ static struct fb_videomode *da8xx_fb_get_videomode(struct platform_device *dev)
 {
 	struct da8xx_lcdc_platform_data *fb_pdata = dev->dev.platform_data;
 	struct fb_videomode *lcdc_info;
+	struct device_node *np = dev->dev.of_node;
 	int i;
 
+	if (np) {
+		lcdc_info = devm_kzalloc(&dev->dev,
+					 sizeof(struct fb_videomode),
+					 GFP_KERNEL);
+		if (!lcdc_info) {
+			dev_err(&dev->dev, "memory allocation failed\n");
+			return NULL;
+		}
+		if (of_get_fb_videomode(np, lcdc_info, OF_USE_NATIVE_MODE)) {
+			dev_err(&dev->dev, "timings not available in DT\n");
+			return NULL;
+		}
+		return lcdc_info;
+	}
+
 	for (i = 0, lcdc_info = known_lcd_panels;
 		i < ARRAY_SIZE(known_lcd_panels); i++, lcdc_info++) {
 		if (strcmp(fb_pdata->type, lcdc_info->name) = 0)
-- 
1.7.12

[PATCH v5 10/12] video: da8xx-fb: ensure pdata only for non-dt

[Afzal Mohammed]

This driver is DT probe-able, hence ensure presence of platform data
only for non-DT boot.

Signed-off-by: Afzal Mohammed <afzal@ti.com>
---
 drivers/video/da8xx-fb.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/video/da8xx-fb.c b/drivers/video/da8xx-fb.c
index 0c68712..1c1a616 100644
--- a/drivers/video/da8xx-fb.c
+++ b/drivers/video/da8xx-fb.c
@@ -1303,7 +1303,7 @@ static int fb_probe(struct platform_device *device)
 	int ret;
 	unsigned long ulcm;
 
-	if (fb_pdata = NULL) {
+	if (fb_pdata = NULL && !device->dev.of_node) {
 		dev_err(&device->dev, "Can not get platform data\n");
 		return -ENOENT;
 	}
-- 
1.7.12

[PATCH v5 11/12] video: da8xx-fb: setup struct lcd_ctrl_config for dt

[Afzal Mohammed]

strcut lcd_ctrl_config information required for driver is currently
obtained via platform data. To handle DT probing, create
lcd_ctrl_config and populate it with default values, these values are
sufficient for the panels so far used with this controller to work.

Signed-off-by: Afzal Mohammed <afzal@ti.com>
---
 drivers/video/da8xx-fb.c | 34 +++++++++++++++++++++++++++++++++-
 1 file changed, 33 insertions(+), 1 deletion(-)

diff --git a/drivers/video/da8xx-fb.c b/drivers/video/da8xx-fb.c
index 1c1a616..5455682 100644
--- a/drivers/video/da8xx-fb.c
+++ b/drivers/video/da8xx-fb.c
@@ -1254,6 +1254,35 @@ static struct fb_ops da8xx_fb_ops = {
 	.fb_blank = cfb_blank,
 };
 
+static struct lcd_ctrl_config *da8xx_fb_create_cfg(struct platform_device *dev)
+{
+	struct lcd_ctrl_config *cfg;
+
+	cfg = devm_kzalloc(&dev->dev, sizeof(struct fb_videomode), GFP_KERNEL);
+	if (!cfg) {
+		dev_err(&dev->dev, "memory allocation failed\n");
+		return NULL;
+	}
+
+	/* default values */
+
+	if (lcd_revision = LCD_VERSION_1)
+		cfg->bpp = 16;
+	else
+		cfg->bpp = 32;
+
+	/*
+	 * For panels so far used with this LCDC, below statement is sufficient.
+	 * For new panels, if required, struct lcd_ctrl_cfg fields to be updated
+	 * with additional/modified values. Those values would have to be then
+	 * obtained from dt(requiring new dt bindings).
+	 */
+
+	cfg->panel_shade = COLOR_ACTIVE;
+
+	return cfg;
+}
+
 static struct fb_videomode *da8xx_fb_get_videomode(struct platform_device *dev)
 {
 	struct da8xx_lcdc_platform_data *fb_pdata = dev->dev.platform_data;
@@ -1345,7 +1374,10 @@ static int fb_probe(struct platform_device *device)
 		break;
 	}
 
-	lcd_cfg = (struct lcd_ctrl_config *)fb_pdata->controller_data;
+	if (device->dev.of_node)
+		lcd_cfg = da8xx_fb_create_cfg(device);
+	else
+		lcd_cfg = (struct lcd_ctrl_config *)fb_pdata->controller_data;
 
 	if (!lcd_cfg) {
 		ret = -EINVAL;
-- 
1.7.12

[PATCH v5 12/12] video: da8xx-fb: set upstream clock rate (if reqd)

[Afzal Mohammed]

LCDC IP has a clock divider to adjust pixel clock, this limits pixel
clock range to fck/255 - fck/2(fck - rate of input clock to LCDC IP).
In the case of AM335x, where this IP is present, default fck is not
sufficient to provide normal pixel clock rates, hence rendering this
driver unusable on AM335x.

If input clock too is configurable, allowable range of pixel clock
would increase. Here initially it is checked whether with present fck,
divider in IP could be configured to obtain required rate, if not,
fck is adjusted. This makes it usable on AM335x.

Note:
Another solution would be to model an inherited basic clock divider of
CCF, an advantage would be a better possible resolution for pixel clk.
And trying to instantiate a CCF clock would mean that to be consistent,
3 bits being turned on to enable clocks of LCDC IP would have to be
modeled as gate clocks. Now that would bring in a total of 4 clocks,
including necessity to create a new inherited divider clock, and that
mean a branch of clock tree would be present in LCDC driver. This
would add complexity to LCDC driver bringing in considerable amount
of clock handling code, and this would not bring in much advantage
for existing use cases other than providing a higher resolution of
pixel clock. And existing use cases work without relying on clock
modeling. Another fact is that out of the two platform's using this
driver DaVinci is not yet converted to CCF. In future if higher
resolution of pixel clock is required, and probably after DaVinci is
CCF'ed, modeling clock nodes inside driver may be considered.

Signed-off-by: Afzal Mohammed <afzal@ti.com>
---

v5: use v2 method of configuring pixel clock rate instead of modeling
    CCF clock nodes in driver, i.e. set divider if rate is within
    the range that is configurable with existing input clock rate,
    else change input clock rate as required.
v4: use new registration for clock divider having minimum divider
    requirement and have ifdef'ery in a better way
v3: model CCF clock divider with parent propogation if CCF selected
v2: new patch

 drivers/video/da8xx-fb.c | 76 ++++++++++++++++++++++++++++++++++++------------
 1 file changed, 58 insertions(+), 18 deletions(-)

diff --git a/drivers/video/da8xx-fb.c b/drivers/video/da8xx-fb.c
index 5455682..09dfa12 100644
--- a/drivers/video/da8xx-fb.c
+++ b/drivers/video/da8xx-fb.c
@@ -133,6 +133,9 @@
 #define WSI_TIMEOUT	50
 #define PALETTE_SIZE	256
 
+#define	CLK_MIN_DIV	2
+#define	CLK_MAX_DIV	255
+
 static void __iomem *da8xx_fb_reg_base;
 static struct resource *lcdc_regs;
 static unsigned int lcd_revision;
@@ -683,23 +686,21 @@ static void da8xx_fb_lcd_reset(void)
 	}
 }
 
-static inline unsigned da8xx_fb_calc_clk_divider(struct da8xx_fb_par *par,
-						 unsigned pixclock)
-{
-	return par->lcd_fck_rate / (PICOS2KHZ(pixclock) * 1000);
-}
-
-static inline unsigned da8xx_fb_round_clk(struct da8xx_fb_par *par,
-					  unsigned pixclock)
+static int da8xx_fb_config_clk_divider(struct da8xx_fb_par *par,
+					      unsigned div, unsigned rate)
 {
-	unsigned div;
+	int ret;
 
-	div = da8xx_fb_calc_clk_divider(par, pixclock);
-	return KHZ2PICOS(par->lcd_fck_rate / (1000 * div));
-}
+	if (par->lcd_fck_rate != rate) {
+		ret = clk_set_rate(par->lcdc_clk, rate);
+		if (IS_ERR_VALUE(ret)) {
+			dev_err(par->dev,
+				"unable to set clock rate at %u\n", rate);
+			return ret;
+		}
+		par->lcd_fck_rate = clk_get_rate(par->lcdc_clk);
+	}
 
-static inline void da8xx_fb_config_clk_divider(unsigned div)
-{
 	/* Configure the LCD clock divisor. */
 	lcdc_write(LCD_CLK_DIVISOR(div) |
 			(LCD_RASTER_MODE & 0x1), LCD_CTRL_REG);
@@ -707,14 +708,49 @@ static inline void da8xx_fb_config_clk_divider(unsigned div)
 	if (lcd_revision = LCD_VERSION_2)
 		lcdc_write(LCD_V2_DMA_CLK_EN | LCD_V2_LIDD_CLK_EN |
 				LCD_V2_CORE_CLK_EN, LCD_CLK_ENABLE_REG);
+
+	return 0;
+}
+
+static unsigned int da8xx_fb_calc_clk_divider(struct da8xx_fb_par *par,
+					      unsigned pixclock,
+					      unsigned *rate)
+{
+	unsigned div;
+
+	pixclock = PICOS2KHZ(pixclock) * 1000;
+
+	*rate = par->lcd_fck_rate;
+
+	if (pixclock < (*rate / CLK_MAX_DIV)) {
+		*rate = clk_round_rate(par->lcdc_clk, pixclock * CLK_MAX_DIV);
+		div = CLK_MAX_DIV;
+	} else if (pixclock > (*rate / CLK_MIN_DIV)) {
+		*rate = clk_round_rate(par->lcdc_clk, pixclock * CLK_MIN_DIV);
+		div = CLK_MIN_DIV;
+	} else {
+		div = *rate / pixclock;
+	}
+
+	return div;
 }
 
-static inline void da8xx_fb_calc_config_clk_divider(struct da8xx_fb_par *par,
+static inline int da8xx_fb_calc_config_clk_divider(struct da8xx_fb_par *par,
 						    struct fb_videomode *mode)
 {
-	unsigned div = da8xx_fb_calc_clk_divider(par, mode->pixclock);
+	unsigned rate;
+	unsigned div = da8xx_fb_calc_clk_divider(par, mode->pixclock, &rate);
 
-	da8xx_fb_config_clk_divider(div);
+	return da8xx_fb_config_clk_divider(par, div, rate);
+}
+
+static inline unsigned da8xx_fb_round_clk(struct da8xx_fb_par *par,
+					  unsigned pixclock)
+{
+	unsigned div, rate;
+
+	div = da8xx_fb_calc_clk_divider(par, pixclock, &rate);
+	return KHZ2PICOS(rate / (1000 * div));
 }
 
 static int lcd_init(struct da8xx_fb_par *par, const struct lcd_ctrl_config *cfg,
@@ -723,7 +759,11 @@ static int lcd_init(struct da8xx_fb_par *par, const struct lcd_ctrl_config *cfg,
 	u32 bpp;
 	int ret = 0;
 
-	da8xx_fb_calc_config_clk_divider(par, panel);
+	ret = da8xx_fb_calc_config_clk_divider(par, panel);
+	if (IS_ERR_VALUE(ret)) {
+		dev_err(par->dev, "unable to configure clock\n");
+		return ret;
+	}
 
 	if (panel->sync & FB_SYNC_CLK_INVERT)
 		lcdc_write((lcdc_read(LCD_RASTER_TIMING_2_REG) |
-- 
1.7.12