[PATCH 4/6] video: mxsfb: get display timings from device tree
Shawn Guo
shawn.guo at linaro.org
Thu Mar 14 16:53:28 EST 2013
Use videomode helpers to get display timings and configurations from
device tree when platform_data is absent.
Signed-off-by: Shawn Guo <shawn.guo at linaro.org>
---
Documentation/devicetree/bindings/fb/mxsfb.txt | 34 +++++++
drivers/video/Kconfig | 2 +
drivers/video/mxsfb.c | 118 ++++++++++++++++++++++--
3 files changed, 144 insertions(+), 10 deletions(-)
diff --git a/Documentation/devicetree/bindings/fb/mxsfb.txt b/Documentation/devicetree/bindings/fb/mxsfb.txt
index b41e5e52..7ba3b76 100644
--- a/Documentation/devicetree/bindings/fb/mxsfb.txt
+++ b/Documentation/devicetree/bindings/fb/mxsfb.txt
@@ -5,10 +5,20 @@ Required properties:
imx23 and imx28.
- reg: Address and length of the register set for lcdif
- interrupts: Should contain lcdif interrupts
+- display : phandle to display node (see below for details)
Optional properties:
- panel-enable-gpios : Should specify the gpio for panel enable
+* display node
+
+Required properties:
+- bits-per-pixel : <16> for RGB565, <32> for RGB888/666.
+- bus-width : number of data lines. Could be <8>, <16>, <18> or <24>.
+
+Required sub-node:
+- display-timings : Refer to binding doc display-timing.txt for details.
+
Examples:
lcdif at 80030000 {
@@ -16,4 +26,28 @@ lcdif at 80030000 {
reg = <0x80030000 2000>;
interrupts = <38 86>;
panel-enable-gpios = <&gpio3 30 0>;
+
+ display: display {
+ bits-per-pixel = <32>;
+ bus-width = <24>;
+
+ display-timings {
+ native-mode = <&timing0>;
+ timing0: timing0 {
+ clock-frequency = <33500000>;
+ hactive = <800>;
+ vactive = <480>;
+ hfront-porch = <164>;
+ hback-porch = <89>;
+ hsync-len = <10>;
+ vback-porch = <23>;
+ vfront-porch = <10>;
+ vsync-len = <10>;
+ hsync-active = <0>;
+ vsync-active = <0>;
+ de-active = <1>;
+ pixelclk-active = <0>;
+ };
+ };
+ };
};
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index 4c1546f..e7718fd 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -2437,6 +2437,8 @@ config FB_MXS
select FB_CFB_FILLRECT
select FB_CFB_COPYAREA
select FB_CFB_IMAGEBLIT
+ select FB_MODE_HELPERS
+ select OF_VIDEOMODE
help
Framebuffer support for the MXS SoC.
diff --git a/drivers/video/mxsfb.c b/drivers/video/mxsfb.c
index 001983a..cf968c6 100644
--- a/drivers/video/mxsfb.c
+++ b/drivers/video/mxsfb.c
@@ -43,12 +43,14 @@
#include <linux/kernel.h>
#include <linux/of_device.h>
#include <linux/of_gpio.h>
+#include <video/of_display_timing.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/io.h>
#include <linux/pinctrl/consumer.h>
#include <linux/mxsfb.h>
+#include <video/videomode.h>
#define REG_SET 4
#define REG_CLR 8
@@ -677,6 +679,97 @@ static int mxsfb_restore_mode(struct mxsfb_info *host)
return 0;
}
+static int mxsfb_init_fbinfo_dt(struct mxsfb_info *host)
+{
+ struct fb_info *fb_info = &host->fb_info;
+ struct fb_var_screeninfo *var = &fb_info->var;
+ struct device *dev = &host->pdev->dev;
+ struct device_node *np = host->pdev->dev.of_node;
+ struct device_node *display_np;
+ struct device_node *timings_np;
+ struct display_timings *timings;
+ u32 width;
+ int i;
+ int ret = 0;
+
+ display_np = of_parse_phandle(np, "display", 0);
+ if (!display_np) {
+ dev_err(dev, "failed to find display phandle\n");
+ return -ENOENT;
+ }
+
+ ret = of_property_read_u32(display_np, "bus-width", &width);
+ if (ret < 0) {
+ dev_err(dev, "failed to get property bus-width\n");
+ goto put_display_node;
+ }
+
+ switch (width) {
+ case 8:
+ host->ld_intf_width = STMLCDIF_8BIT;
+ break;
+ case 16:
+ host->ld_intf_width = STMLCDIF_16BIT;
+ break;
+ case 18:
+ host->ld_intf_width = STMLCDIF_18BIT;
+ break;
+ case 24:
+ host->ld_intf_width = STMLCDIF_24BIT;
+ break;
+ default:
+ dev_err(dev, "invalid bus-width value\n");
+ ret = -EINVAL;
+ goto put_display_node;
+ }
+
+ ret = of_property_read_u32(display_np, "bits-per-pixel",
+ &var->bits_per_pixel);
+ if (ret < 0) {
+ dev_err(dev, "failed to get property bits-per-pixel\n");
+ goto put_display_node;
+ }
+
+ timings = of_get_display_timings(display_np);
+ if (!timings) {
+ dev_err(dev, "failed to get display timings\n");
+ ret = -ENOENT;
+ goto put_display_node;
+ }
+
+ timings_np = of_find_node_by_name(display_np,
+ "display-timings");
+ if (!timings_np) {
+ dev_err(dev, "failed to find display-timings node\n");
+ ret = -ENOENT;
+ goto put_display_node;
+ }
+
+ for (i = 0; i < of_get_child_count(timings_np); i++) {
+ struct videomode vm;
+ struct fb_videomode fb_vm;
+
+ ret = videomode_from_timing(timings, &vm, i);
+ if (ret < 0)
+ goto put_timings_node;
+ ret = fb_videomode_from_videomode(&vm, &fb_vm);
+ if (ret < 0)
+ goto put_timings_node;
+
+ if (vm.data_flags & DISPLAY_FLAGS_DE_HIGH)
+ fb_vm.sync |= FB_SYNC_DATA_ENABLE_HIGH_ACT;
+ if (vm.data_flags & DISPLAY_FLAGS_PIXDATA_NEGEDGE)
+ fb_vm.sync |= FB_SYNC_DOTCLK_FAILING_ACT;
+ fb_add_videomode(&fb_vm, &fb_info->modelist);
+ }
+
+put_timings_node:
+ of_node_put(timings_np);
+put_display_node:
+ of_node_put(display_np);
+ return ret;
+}
+
static int mxsfb_init_fbinfo(struct mxsfb_info *host)
{
struct fb_info *fb_info = &host->fb_info;
@@ -685,6 +778,7 @@ static int mxsfb_init_fbinfo(struct mxsfb_info *host)
dma_addr_t fb_phys;
void *fb_virt;
unsigned fb_size;
+ int ret;
fb_info->fbops = &mxsfb_ops;
fb_info->flags = FBINFO_FLAG_DEFAULT | FBINFO_READS_FAST;
@@ -694,14 +788,21 @@ static int mxsfb_init_fbinfo(struct mxsfb_info *host)
fb_info->fix.visual = FB_VISUAL_TRUECOLOR,
fb_info->fix.accel = FB_ACCEL_NONE;
- var->bits_per_pixel = pdata->default_bpp ? pdata->default_bpp : 16;
+ if (pdata) {
+ host->ld_intf_width = pdata->ld_intf_width;
+ var->bits_per_pixel =
+ pdata->default_bpp ? pdata->default_bpp : 16;
+ } else {
+ ret = mxsfb_init_fbinfo_dt(host);
+ if (ret)
+ return ret;
+ }
+
var->nonstd = 0;
var->activate = FB_ACTIVATE_NOW;
var->accel_flags = 0;
var->vmode = FB_VMODE_NONINTERLACED;
- host->ld_intf_width = pdata->ld_intf_width;
-
/* Memory allocation for framebuffer */
fb_size = SZ_2M;
fb_virt = alloc_pages_exact(fb_size, GFP_DMA);
@@ -764,11 +865,6 @@ static int mxsfb_probe(struct platform_device *pdev)
if (of_id)
pdev->id_entry = of_id->data;
- if (!pdata) {
- dev_err(&pdev->dev, "No platformdata. Giving up\n");
- return -ENODEV;
- }
-
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
dev_err(&pdev->dev, "Cannot get memory IO resource\n");
@@ -836,8 +932,10 @@ static int mxsfb_probe(struct platform_device *pdev)
if (ret != 0)
goto fb_release;
- for (i = 0; i < pdata->mode_count; i++)
- fb_add_videomode(&pdata->mode_list[i], &fb_info->modelist);
+ if (pdata)
+ for (i = 0; i < pdata->mode_count; i++)
+ fb_add_videomode(&pdata->mode_list[i],
+ &fb_info->modelist);
modelist = list_first_entry(&fb_info->modelist,
struct fb_modelist, list);
--
1.7.9.5
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