[PATCH v2 1/2] video: ARM CLCD: Add DT support
Pawel Moll
pawel.moll at arm.com
Tue Sep 10 06:25:25 EDT 2013
This patch adds basic DT bindings for the PL11x CLCD cells
and make their fbdev driver use them.
Signed-off-by: Pawel Moll <pawel.moll at arm.com>
---
Changes since v1:
- minor code cleanups as suggested by Sylwester Nawrocki
.../devicetree/bindings/video/arm,pl11x.txt | 87 +++++++++
drivers/video/Kconfig | 1 +
drivers/video/amba-clcd.c | 211 +++++++++++++++++++++
3 files changed, 299 insertions(+)
create mode 100644 Documentation/devicetree/bindings/video/arm,pl11x.txt
diff --git a/Documentation/devicetree/bindings/video/arm,pl11x.txt b/Documentation/devicetree/bindings/video/arm,pl11x.txt
new file mode 100644
index 0000000..7eb77aa
--- /dev/null
+++ b/Documentation/devicetree/bindings/video/arm,pl11x.txt
@@ -0,0 +1,87 @@
+* ARM PrimeCell Color LCD (CLCD) Controller PL110/PL111
+
+See also Documentation/devicetree/bindings/arm/primecell.txt
+
+Required properties:
+
+- compatible: must be one of:
+ "arm,pl110", "arm,primecell"
+ "arm,pl111", "arm,primecell"
+- reg: base address and size of the control registers block
+- interrupts: either a single interrupt specifier representing the
+ combined interrupt output (CLCDINTR) or an array of
+ four interrupt specifiers for CLCDMBEINTR,
+ CLCDVCOMPINTR, CLCDLNBUINTR, CLCDFUFINTR; in the
+ latter case interrupt names must be specified
+ (see below)
+- interrupt-names: when four interrupts are specified, their names:
+ "mbe", "vcomp", "lnbu", "fuf"
+ must be specified in order respective to the
+ interrupt specifiers
+- clocks: contains phandle and clock specifier pairs for the entries
+ in the clock-names property. See
+ Documentation/devicetree/binding/clock/clock-bindings.txt
+- clocks names: should contain "clcdclk" and "apb_pclk"
+
+Optional properties:
+
+- video-ram: phandle to a node describing specialized video memory
+ (that is *not* described in the top level "memory" node)
+ that must be used as a framebuffer, eg. due to restrictions
+ of the system interconnect; the node must contain a
+ standard reg property describing the address and the size
+ of the memory area
+- max-framebuffer-size: maximum size in bytes of the framebuffer the
+ system can handle, eg. in terms of available
+ memory bandwidth
+
+In the simplest case of a display panel being connected directly to the
+CLCD, it can be described in the node:
+
+- panel-dimensions: (optional) array of two numbers (width and height)
+ describing physical dimension in mm of the panel
+- panel-type: (required) must be "tft" or "stn", defines panel type
+- panel-tft-interface: (for "tft" panel type) array of 3 numbers defining
+ widths in bits of the R, G and B components
+- panel-tft-rb-swapped: (for "tft" panel type) if present means that
+ the R & B components are swapped on the board
+- panel-stn-color: (for "stn" panel type) if present means that
+ the panel is a colour STN display, if missing
+ is a monochrome display
+- panel-stn-dual: (for "stn" panel type) if present means that there
+ are two STN displays connected
+- panel-stn-4bit: (for monochrome "stn" panel) if present means
+ that the monochrome display is connected
+ via 4 bit-wide interface
+- display-timings: standard display timings sub-node, see
+ Documentation/devicetree/bindings/video/display-timing.txt
+
+Example:
+
+ clcd at 1f0000 {
+ compatible = "arm,pl111", "arm,primecell";
+ reg = <0x1f0000 0x1000>;
+ interrupts = <14>;
+ clocks = <&v2m_oscclk1>, <&smbclk>;
+ clock-names = "clcdclk", "apb_pclk";
+
+ video-ram = <&v2m_vram>;
+ max-framebuffer-size = <614400>; /* 640x480 16bpp */
+
+ panel-type = "tft";
+ panel-tft-interface = <8 8 8>;
+ display-timings {
+ native-mode = <&v2m_clcd_timing0>;
+ v2m_clcd_timing0: vga {
+ clock-frequency = <25175000>;
+ hactive = <640>;
+ hback-porch = <40>;
+ hfront-porch = <24>;
+ hsync-len = <96>;
+ vactive = <480>;
+ vback-porch = <32>;
+ vfront-porch = <11>;
+ vsync-len = <2>;
+ };
+ };
+ };
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index 4cf1e1d..375bf63 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -316,6 +316,7 @@ config FB_ARMCLCD
select FB_CFB_FILLRECT
select FB_CFB_COPYAREA
select FB_CFB_IMAGEBLIT
+ select VIDEOMODE_HELPERS if OF
help
This framebuffer device driver is for the ARM PrimeCell PL110
Colour LCD controller. ARM PrimeCells provide the building
diff --git a/drivers/video/amba-clcd.c b/drivers/video/amba-clcd.c
index 0a2cce7..7f36964 100644
--- a/drivers/video/amba-clcd.c
+++ b/drivers/video/amba-clcd.c
@@ -25,6 +25,11 @@
#include <linux/amba/clcd.h>
#include <linux/clk.h>
#include <linux/hardirq.h>
+#include <linux/dma-mapping.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <video/of_display_timing.h>
+#include <video/of_videomode.h>
#include <asm/sizes.h>
@@ -542,6 +547,209 @@ static int clcdfb_register(struct clcd_fb *fb)
return ret;
}
+#ifdef CONFIG_OF
+static int clcdfb_of_get_tft_panel(struct device_node *node,
+ struct clcd_panel *panel)
+{
+ int err;
+ u32 rgb[3];
+
+ err = of_property_read_u32_array(node, "panel-tft-interface", rgb, 3);
+ if (err)
+ return err;
+
+ /* Bypass pixel clock divider, data output on the falling edge */
+ panel->tim2 = TIM2_BCD | TIM2_IPC;
+
+ /* TFT display, vert. comp. interrupt at the start of the back porch */
+ panel->cntl |= CNTL_LCDTFT | CNTL_LCDVCOMP(1);
+
+ if (rgb[0] >= 4 && rgb[1] >= 4 && rgb[2] >= 4)
+ panel->caps |= CLCD_CAP_444;
+ if (rgb[0] >= 5 && rgb[1] >= 5 && rgb[2] >= 5)
+ panel->caps |= CLCD_CAP_5551;
+ if (rgb[0] >= 5 && rgb[1] >= 6 && rgb[2] >= 5)
+ panel->caps |= CLCD_CAP_565;
+ if (rgb[0] >= 8 && rgb[1] >= 8 && rgb[2] >= 8)
+ panel->caps |= CLCD_CAP_888;
+
+ if (of_get_property(node, "panel-tft-rb-swapped", NULL))
+ panel->caps &= ~CLCD_CAP_RGB;
+ else
+ panel->caps &= ~CLCD_CAP_BGR;
+
+ return 0;
+}
+
+static int clcdfb_snprintf_mode(char *buf, int size, struct fb_videomode *mode)
+{
+ return snprintf(buf, size, "%ux%u@%u", mode->xres, mode->yres,
+ mode->refresh);
+}
+
+static int clcdfb_of_init_display(struct clcd_fb *fb)
+{
+ struct device_node *node = fb->dev->dev.of_node;
+ int err, len;
+ char *mode_name;
+ u32 max_size;
+ u32 dimensions[2];
+ const char *panel_type;
+
+ fb->panel = devm_kzalloc(&fb->dev->dev, sizeof(*fb->panel), GFP_KERNEL);
+ if (!fb->panel)
+ return -ENOMEM;
+
+ err = of_get_fb_videomode(node, &fb->panel->mode, OF_USE_NATIVE_MODE);
+ if (err)
+ return err;
+
+ len = clcdfb_snprintf_mode(NULL, 0, &fb->panel->mode);
+ mode_name = devm_kzalloc(&fb->dev->dev, len + 1, GFP_KERNEL);
+ clcdfb_snprintf_mode(mode_name, len + 1, &fb->panel->mode);
+ fb->panel->mode.name = mode_name;
+
+ err = of_property_read_u32(node, "max-framebuffer-size", &max_size);
+ if (!err)
+ fb->panel->bpp = max_size / (fb->panel->mode.xres *
+ fb->panel->mode.yres) * 8;
+ else
+ fb->panel->bpp = 32;
+
+#ifdef CONFIG_CPU_BIG_ENDIAN
+ fb->panel->cntl |= CNTL_BEBO;
+#endif
+
+ if (of_property_read_u32_array(node, "panel-dimensions",
+ dimensions, 2) == 0) {
+ fb->panel->width = dimensions[0];
+ fb->panel->height = dimensions[1];
+ } else {
+ fb->panel->width = -1;
+ fb->panel->height = -1;
+ }
+
+ panel_type = of_get_property(node, "panel-type", &len);
+ if (strncmp(panel_type, "tft", len) == 0)
+ return clcdfb_of_get_tft_panel(node, fb->panel);
+ else
+ return -EINVAL;
+}
+
+static int clcdfb_of_vram_setup(struct clcd_fb *fb)
+{
+ struct device_node *node = of_parse_phandle(fb->dev->dev.of_node,
+ "video-ram", 0);
+ u64 size;
+ int err;
+
+ if (!node)
+ return -ENODEV;
+
+ err = clcdfb_of_init_display(fb);
+ if (err)
+ return err;
+
+ fb->fb.screen_base = of_iomap(node, 0);
+ if (!fb->fb.screen_base)
+ return -ENOMEM;
+
+ fb->fb.fix.smem_start = of_translate_address(node,
+ of_get_address(node, 0, &size, NULL));
+ fb->fb.fix.smem_len = size;
+
+ return 0;
+}
+
+static int clcdfb_of_vram_mmap(struct clcd_fb *fb, struct vm_area_struct *vma)
+{
+ unsigned long off, user_size, kernel_size;
+
+ off = vma->vm_pgoff << PAGE_SHIFT;
+ user_size = vma->vm_end - vma->vm_start;
+ kernel_size = fb->fb.fix.smem_len;
+
+ if (off >= kernel_size || user_size > (kernel_size - off))
+ return -ENXIO;
+
+ return remap_pfn_range(vma, vma->vm_start,
+ __phys_to_pfn(fb->fb.fix.smem_start) + vma->vm_pgoff,
+ user_size,
+ pgprot_writecombine(vma->vm_page_prot));
+}
+
+static void clcdfb_of_vram_remove(struct clcd_fb *fb)
+{
+ iounmap(fb->fb.screen_base);
+}
+
+static int clcdfb_of_dma_setup(struct clcd_fb *fb)
+{
+ unsigned long framesize;
+ dma_addr_t dma;
+ int err;
+
+ err = clcdfb_of_init_display(fb);
+ if (err)
+ return err;
+
+ framesize = fb->panel->mode.xres * fb->panel->mode.yres *
+ fb->panel->bpp / 8;
+ fb->fb.screen_base = dma_alloc_writecombine(&fb->dev->dev, framesize,
+ &dma, GFP_KERNEL);
+ if (!fb->fb.screen_base)
+ return -ENOMEM;
+
+ fb->fb.fix.smem_start = dma;
+ fb->fb.fix.smem_len = framesize;
+
+ return 0;
+}
+
+static int clcdfb_of_dma_mmap(struct clcd_fb *fb, struct vm_area_struct *vma)
+{
+ return dma_mmap_writecombine(&fb->dev->dev, vma, fb->fb.screen_base,
+ fb->fb.fix.smem_start, fb->fb.fix.smem_len);
+}
+
+static void clcdfb_of_dma_remove(struct clcd_fb *fb)
+{
+ dma_free_writecombine(&fb->dev->dev, fb->fb.fix.smem_len,
+ fb->fb.screen_base, fb->fb.fix.smem_start);
+}
+
+static struct clcd_board *clcdfb_of_get_board(struct amba_device *dev)
+{
+ struct clcd_board *board = devm_kzalloc(&dev->dev, sizeof(*board),
+ GFP_KERNEL);
+ struct device_node *node = dev->dev.of_node;
+
+ if (!board)
+ return NULL;
+
+ board->name = of_node_full_name(node);
+ board->caps = CLCD_CAP_ALL;
+ board->check = clcdfb_check;
+ board->decode = clcdfb_decode;
+ if (of_find_property(node, "video-ram", NULL)) {
+ board->setup = clcdfb_of_vram_setup;
+ board->mmap = clcdfb_of_vram_mmap;
+ board->remove = clcdfb_of_vram_remove;
+ } else {
+ board->setup = clcdfb_of_dma_setup;
+ board->mmap = clcdfb_of_dma_mmap;
+ board->remove = clcdfb_of_dma_remove;
+ }
+
+ return board;
+}
+#else
+static struct clcd_board *clcdfb_of_get_board(struct amba_dev *dev)
+{
+ return NULL;
+}
+#endif
+
static int clcdfb_probe(struct amba_device *dev, const struct amba_id *id)
{
struct clcd_board *board = dev->dev.platform_data;
@@ -549,6 +757,9 @@ static int clcdfb_probe(struct amba_device *dev, const struct amba_id *id)
int ret;
if (!board)
+ board = clcdfb_of_get_board(dev);
+
+ if (!board)
return -EINVAL;
ret = amba_request_regions(dev, NULL);
--
1.8.1.2
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