[PATCH v4 2/2] video: imxfb: Add DT support
Markus Pargmann
mpa at pengutronix.de
Thu Apr 18 09:03:03 EDT 2013
Add devicetree support for imx framebuffer driver. It uses the generic
display bindings and helper functions.
Signed-off-by: Markus Pargmann <mpa at pengutronix.de>
Cc: Fabio Estevam <festevam at gmail.com>
Cc: Mark Rutland <mark.rutland at arm.com>
---
Notes:
Changes in v4:
- Remove eukrea specific dmacr property.
- Add optional dmacr property. If not present, the dmacr reset value is not
changed.
Changes in v3:
- Fix returncodes of of_read_mode function and print error messages
- Introduce a lower bound check for bits per pixel
- Calculate correct bytes per pixel value before using it for the calculation of
memory size
- Change DT property names
Changes in v2:
- Removed pwmr register property
- Cleanup of devicetree binding documentation
- Use default values for pwmr and lscr1
.../devicetree/bindings/video/fsl,imx-fb.txt | 51 ++++++
drivers/video/imxfb.c | 194 +++++++++++++++++----
2 files changed, 210 insertions(+), 35 deletions(-)
create mode 100644 Documentation/devicetree/bindings/video/fsl,imx-fb.txt
diff --git a/Documentation/devicetree/bindings/video/fsl,imx-fb.txt b/Documentation/devicetree/bindings/video/fsl,imx-fb.txt
new file mode 100644
index 0000000..aff16a4
--- /dev/null
+++ b/Documentation/devicetree/bindings/video/fsl,imx-fb.txt
@@ -0,0 +1,51 @@
+Freescale imx21 Framebuffer
+
+This framebuffer driver supports devices imx1, imx21, imx25, and imx27.
+
+Required properties:
+- compatible : "fsl,<chip>-fb", chip should be imx1 or imx21
+- reg : Should contain 1 register ranges(address and length)
+- interrupts : One interrupt of the fb dev
+
+Required nodes:
+- display: Phandle to a display node as described in
+ Documentation/devicetree/bindings/video/display-timing.txt
+ Additional, the display node has to define properties:
+ - fsl,bpp: Bits per pixel
+ - fsl,pcr: LCDC PCR value
+
+Optional properties:
+- fsl,dmacr: DMA Control Register value. This is optional. By default, the
+ register is not modified as recommended by the datasheet.
+- fsl,lscr1: LCDC Sharp Configuration Register value.
+
+Example:
+
+ imxfb: fb at 10021000 {
+ compatible = "fsl,imx27-fb", "fsl,imx21-fb";
+ interrupts = <61>;
+ reg = <0x10021000 0x1000>;
+ display = <&display0>;
+ };
+
+ ...
+
+ display0: display0 {
+ model = "Primeview-PD050VL1";
+ native-mode = <&timing_disp0>;
+ fsl,bpp = <16>; /* non-standard but required */
+ fsl,pcr = <0xf0c88080>; /* non-standard but required */
+ display-timings {
+ timing_disp0: 640x480 {
+ hactive = <640>;
+ vactive = <480>;
+ hback-porch = <112>;
+ hfront-porch = <36>;
+ hsync-len = <32>;
+ vback-porch = <33>;
+ vfront-porch = <33>;
+ vsync-len = <2>;
+ clock-frequency = <25000000>;
+ };
+ };
+ };
diff --git a/drivers/video/imxfb.c b/drivers/video/imxfb.c
index ef2b587..e0230f8 100644
--- a/drivers/video/imxfb.c
+++ b/drivers/video/imxfb.c
@@ -32,6 +32,12 @@
#include <linux/io.h>
#include <linux/math64.h>
#include <linux/uaccess.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+
+#include <video/of_display_timing.h>
+#include <video/of_videomode.h>
+#include <video/videomode.h>
#include <linux/platform_data/video-imxfb.h>
@@ -117,10 +123,11 @@
#define LGWCR_GWAV(alpha) (((alpha) & 0xff) << 24)
#define LGWCR_GWE (1 << 22)
+#define IMXFB_LSCR1_DEFAULT 0x00120300
+
/* Used fb-mode. Can be set on kernel command line, therefore file-static. */
static const char *fb_mode;
-
/*
* These are the bitfields for each
* display depth that we support.
@@ -192,6 +199,19 @@ static struct platform_device_id imxfb_devtype[] = {
};
MODULE_DEVICE_TABLE(platform, imxfb_devtype);
+static struct of_device_id imxfb_of_dev_id[] = {
+ {
+ .compatible = "fsl,imx1-fb",
+ .data = &imxfb_devtype[IMX1_FB],
+ }, {
+ .compatible = "fsl,imx21-fb",
+ .data = &imxfb_devtype[IMX21_FB],
+ }, {
+ /* sentinel */
+ }
+};
+MODULE_DEVICE_TABLE(of, imxfb_of_dev_id);
+
static inline int is_imx1_fb(struct imxfb_info *fbi)
{
return fbi->devtype == IMX1_FB;
@@ -324,6 +344,9 @@ static const struct imx_fb_videomode *imxfb_find_mode(struct imxfb_info *fbi)
struct imx_fb_videomode *m;
int i;
+ if (!fb_mode)
+ return &fbi->mode[0];
+
for (i = 0, m = &fbi->mode[0]; i < fbi->num_modes; i++, m++) {
if (!strcmp(m->mode.name, fb_mode))
return m;
@@ -479,6 +502,9 @@ static int imxfb_bl_update_status(struct backlight_device *bl)
struct imxfb_info *fbi = bl_get_data(bl);
int brightness = bl->props.brightness;
+ if (!fbi->pwmr)
+ return 0;
+
if (bl->props.power != FB_BLANK_UNBLANK)
brightness = 0;
if (bl->props.fb_blank != FB_BLANK_UNBLANK)
@@ -719,10 +745,14 @@ static int imxfb_activate_var(struct fb_var_screeninfo *var, struct fb_info *inf
writel(fbi->pcr, fbi->regs + LCDC_PCR);
#ifndef PWMR_BACKLIGHT_AVAILABLE
- writel(fbi->pwmr, fbi->regs + LCDC_PWMR);
+ if (fbi->pwmr)
+ writel(fbi->pwmr, fbi->regs + LCDC_PWMR);
#endif
writel(fbi->lscr1, fbi->regs + LCDC_LSCR1);
- writel(fbi->dmacr, fbi->regs + LCDC_DMACR);
+
+ /* dmacr = 0 is no valid value, as we need DMA control marks. */
+ if (fbi->dmacr)
+ writel(fbi->dmacr, fbi->regs + LCDC_DMACR);
return 0;
}
@@ -758,13 +788,12 @@ static int imxfb_resume(struct platform_device *dev)
#define imxfb_resume NULL
#endif
-static int __init imxfb_init_fbinfo(struct platform_device *pdev)
+static int imxfb_init_fbinfo(struct platform_device *pdev)
{
struct imx_fb_platform_data *pdata = pdev->dev.platform_data;
struct fb_info *info = dev_get_drvdata(&pdev->dev);
struct imxfb_info *fbi = info->par;
- struct imx_fb_videomode *m;
- int i;
+ struct device_node *np;
pr_debug("%s\n",__func__);
@@ -795,41 +824,95 @@ static int __init imxfb_init_fbinfo(struct platform_device *pdev)
info->fbops = &imxfb_ops;
info->flags = FBINFO_FLAG_DEFAULT |
FBINFO_READS_FAST;
- info->var.grayscale = pdata->cmap_greyscale;
- fbi->cmap_inverse = pdata->cmap_inverse;
- fbi->cmap_static = pdata->cmap_static;
- fbi->lscr1 = pdata->lscr1;
- fbi->dmacr = pdata->dmacr;
- fbi->pwmr = pdata->pwmr;
- fbi->lcd_power = pdata->lcd_power;
- fbi->backlight_power = pdata->backlight_power;
-
- for (i = 0, m = &pdata->mode[0]; i < pdata->num_modes; i++, m++)
- info->fix.smem_len = max_t(size_t, info->fix.smem_len,
- m->mode.xres * m->mode.yres * m->bpp / 8);
+ if (pdata) {
+ info->var.grayscale = pdata->cmap_greyscale;
+ fbi->cmap_inverse = pdata->cmap_inverse;
+ fbi->cmap_static = pdata->cmap_static;
+ fbi->lscr1 = pdata->lscr1;
+ fbi->dmacr = pdata->dmacr;
+ fbi->pwmr = pdata->pwmr;
+ fbi->lcd_power = pdata->lcd_power;
+ fbi->backlight_power = pdata->backlight_power;
+ } else {
+ np = pdev->dev.of_node;
+ info->var.grayscale = of_property_read_bool(np,
+ "cmap-greyscale");
+ fbi->cmap_inverse = of_property_read_bool(np, "cmap-inverse");
+ fbi->cmap_static = of_property_read_bool(np, "cmap-static");
+
+ fbi->lscr1 = IMXFB_LSCR1_DEFAULT;
+ of_property_read_u32(np, "fsl,lscr1", &fbi->lscr1);
+
+ of_property_read_u32(np, "fsl,dmacr", &fbi->dmacr);
+
+ /* These two function pointers could be used by some specific
+ * platforms. */
+ fbi->lcd_power = NULL;
+ fbi->backlight_power = NULL;
+ }
+
+ return 0;
+}
+
+static int imxfb_of_read_mode(struct device *dev, struct device_node *np,
+ struct imx_fb_videomode *imxfb_mode)
+{
+ int ret;
+ struct fb_videomode *of_mode = &imxfb_mode->mode;
+ u32 bpp;
+ u32 pcr;
+
+ ret = of_property_read_string(np, "model", &of_mode->name);
+ if (ret)
+ of_mode->name = NULL;
+
+ ret = of_get_fb_videomode(np, of_mode, OF_USE_NATIVE_MODE);
+ if (ret) {
+ dev_err(dev, "Failed to get videomode from DT\n");
+ return ret;
+ }
+
+ ret = of_property_read_u32(np, "fsl,bpp", &bpp);
+ ret |= of_property_read_u32(np, "fsl,pcr", &pcr);
+
+ if (ret) {
+ dev_err(dev, "Failed to read bpp and pcr from DT\n");
+ return -EINVAL;
+ }
+
+ if (bpp < 1 || bpp > 255) {
+ dev_err(dev, "Bits per pixel have to be between 1 and 255\n");
+ return -EINVAL;
+ }
+
+ imxfb_mode->bpp = bpp;
+ imxfb_mode->pcr = pcr;
return 0;
}
-static int __init imxfb_probe(struct platform_device *pdev)
+static int imxfb_probe(struct platform_device *pdev)
{
struct imxfb_info *fbi;
struct fb_info *info;
struct imx_fb_platform_data *pdata;
struct resource *res;
+ struct imx_fb_videomode *m;
+ const struct of_device_id *of_id;
int ret, i;
+ int bytes_per_pixel;
dev_info(&pdev->dev, "i.MX Framebuffer driver\n");
+ of_id = of_match_device(imxfb_of_dev_id, &pdev->dev);
+ if (of_id)
+ pdev->id_entry = of_id->data;
+
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -ENODEV;
pdata = pdev->dev.platform_data;
- if (!pdata) {
- dev_err(&pdev->dev,"No platform_data available\n");
- return -ENOMEM;
- }
info = framebuffer_alloc(sizeof(struct imxfb_info), &pdev->dev);
if (!info)
@@ -837,15 +920,55 @@ static int __init imxfb_probe(struct platform_device *pdev)
fbi = info->par;
- if (!fb_mode)
- fb_mode = pdata->mode[0].mode.name;
-
platform_set_drvdata(pdev, info);
ret = imxfb_init_fbinfo(pdev);
if (ret < 0)
goto failed_init;
+ if (pdata) {
+ if (!fb_mode)
+ fb_mode = pdata->mode[0].mode.name;
+
+ fbi->mode = pdata->mode;
+ fbi->num_modes = pdata->num_modes;
+ } else {
+ struct device_node *display_np;
+ fb_mode = NULL;
+
+ display_np = of_parse_phandle(pdev->dev.of_node, "display", 0);
+ if (!display_np) {
+ dev_err(&pdev->dev, "No display defined in devicetree\n");
+ ret = -EINVAL;
+ goto failed_of_parse;
+ }
+
+ /*
+ * imxfb does not support more modes, we choose only the native
+ * mode.
+ */
+ fbi->num_modes = 1;
+
+ fbi->mode = devm_kzalloc(&pdev->dev,
+ sizeof(struct imx_fb_videomode), GFP_KERNEL);
+ if (!fbi->mode) {
+ ret = -ENOMEM;
+ goto failed_of_parse;
+ }
+
+ ret = imxfb_of_read_mode(&pdev->dev, display_np, fbi->mode);
+ if (ret)
+ goto failed_of_parse;
+ }
+
+ /* Calculate maximum bytes used per pixel. In most cases this should
+ * be the same as m->bpp/8 */
+ m = &fbi->mode[0];
+ bytes_per_pixel = (m->bpp + 7) / 8;
+ for (i = 0; i < fbi->num_modes; i++, m++)
+ info->fix.smem_len = max_t(size_t, info->fix.smem_len,
+ m->mode.xres * m->mode.yres * bytes_per_pixel);
+
res = request_mem_region(res->start, resource_size(res),
DRIVER_NAME);
if (!res) {
@@ -878,7 +1001,8 @@ static int __init imxfb_probe(struct platform_device *pdev)
goto failed_ioremap;
}
- if (!pdata->fixed_screen_cpu) {
+ /* Seems not being used by anyone, so no support for oftree */
+ if (!pdata || !pdata->fixed_screen_cpu) {
fbi->map_size = PAGE_ALIGN(info->fix.smem_len);
fbi->map_cpu = dma_alloc_writecombine(&pdev->dev,
fbi->map_size, &fbi->map_dma, GFP_KERNEL);
@@ -903,18 +1027,16 @@ static int __init imxfb_probe(struct platform_device *pdev)
info->fix.smem_start = fbi->screen_dma;
}
- if (pdata->init) {
+ if (pdata && pdata->init) {
ret = pdata->init(fbi->pdev);
if (ret)
goto failed_platform_init;
}
- fbi->mode = pdata->mode;
- fbi->num_modes = pdata->num_modes;
INIT_LIST_HEAD(&info->modelist);
- for (i = 0; i < pdata->num_modes; i++)
- fb_add_videomode(&pdata->mode[i].mode, &info->modelist);
+ for (i = 0; i < fbi->num_modes; i++)
+ fb_add_videomode(&fbi->mode[i].mode, &info->modelist);
/*
* This makes sure that our colour bitfield
@@ -944,10 +1066,10 @@ static int __init imxfb_probe(struct platform_device *pdev)
failed_register:
fb_dealloc_cmap(&info->cmap);
failed_cmap:
- if (pdata->exit)
+ if (pdata && pdata->exit)
pdata->exit(fbi->pdev);
failed_platform_init:
- if (!pdata->fixed_screen_cpu)
+ if (pdata && !pdata->fixed_screen_cpu)
dma_free_writecombine(&pdev->dev,fbi->map_size,fbi->map_cpu,
fbi->map_dma);
failed_map:
@@ -956,6 +1078,7 @@ failed_ioremap:
failed_getclock:
release_mem_region(res->start, resource_size(res));
failed_req:
+failed_of_parse:
kfree(info->pseudo_palette);
failed_init:
platform_set_drvdata(pdev, NULL);
@@ -980,7 +1103,7 @@ static int imxfb_remove(struct platform_device *pdev)
unregister_framebuffer(info);
pdata = pdev->dev.platform_data;
- if (pdata->exit)
+ if (pdata && pdata->exit)
pdata->exit(fbi->pdev);
fb_dealloc_cmap(&info->cmap);
@@ -1009,6 +1132,7 @@ static struct platform_driver imxfb_driver = {
.shutdown = imxfb_shutdown,
.driver = {
.name = DRIVER_NAME,
+ .of_match_table = imxfb_of_dev_id,
},
.id_table = imxfb_devtype,
};
--
1.8.1.5
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