[PATCH v4 2/2] video: imxfb: Add DT support
Jean-Christophe PLAGNIOL-VILLARD
plagnioj at jcrosoft.com
Thu Apr 18 12:06:14 EDT 2013
On 15:03 Thu 18 Apr , Markus Pargmann wrote:
> 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";
you put both when in the doc you request one
> + interrupts = <61>;
> + reg = <0x10021000 0x1000>;
> + display = <&display0>;
> + };
> +
> + ...
> +
> + display0: display0 {
> + model = "Primeview-PD050VL1";
> + native-mode = <&timing_disp0>;
> + fsl,bpp = <16>; /* non-standard but required */
there is a generic binding bit-per-pixel use a cross other IP
> + 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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