// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/drivers/video/vt8500lcdfb.c
*
* Copyright (C) 2010 Alexey Charkov <alchark@gmail.com>
*
* Based on skeletonfb.c and pxafb.c
*/
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/errno.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/wait.h>
#include <video/of_display_timing.h>
#include "vt8500lcdfb.h"
#include "wmt_ge_rops.h"
#ifdef CONFIG_OF
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/memblock.h>
#endif
#define to_vt8500lcd_info(__info) container_of(__info, \
struct vt8500lcd_info, fb)
static int vt8500lcd_set_par(struct fb_info *info)
{
struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
int reg_bpp = 5; /* 16bpp */
int i;
unsigned long control0;
if (!fbi)
return -EINVAL;
if (info->var.bits_per_pixel <= 8) {
/* palettized */
info->var.red.offset = 0;
info->var.red.length = info->var.bits_per_pixel;
info->var.red.msb_right = 0;
info->var.green.offset = 0;
info->var.green.length = info->var.bits_per_pixel;
info->var.green.msb_right = 0;
info->var.blue.offset = 0;
info->var.blue.length = info->var.bits_per_pixel;
info->var.blue.msb_right = 0;
info->var.transp.offset = 0;
info->var.transp.length = 0;
info->var.transp.msb_right = 0;
info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
info->fix.line_length = info->var.xres_virtual /
(8/info->var.bits_per_pixel);
} else {
/* non-palettized */
info->var.transp.offset = 0;
info->var.transp.length = 0;
info->var.transp.msb_right = 0;
if (info->var.bits_per_pixel == 16) {
/* RGB565 */
info->var.red.offset = 11;
info->var.red.length = 5;
info->var.red.msb_right = 0;
info->var.green.offset = 5;
info->var.green.length = 6;
info->var.green.msb_right = 0;
info->var.blue.offset = 0;
info->var.blue.length = 5;
info->var.blue.msb_right = 0;
} else {
/* Equal depths per channel */
info->var.red.offset = info->var.bits_per_pixel
* 2 / 3;
info->var.red.length = info->var.bits_per_pixel / 3;
info->var.red.msb_right = 0;
info->var.green.offset = info->var.bits_per_pixel / 3;
info->var.green.length = info->var.bits_per_pixel / 3;
info->var.green.msb_right = 0;
info->var.blue.offset = 0;
info->var.blue.length = info->var.bits_per_pixel / 3;
info->var.blue.msb_right = 0;
}
info->fix.visual = FB_VISUAL_TRUECOLOR;
info->fix.line_length = info->var.bits_per_pixel > 16 ?
info->var.xres_virtual << 2 :
info->var.xres_virtual << 1;
}
for (i = 0; i < 8; i++) {
if (bpp_values[i] == info->var.bits_per_pixel)
reg_bpp = i;
}
control0 = readl(fbi->regbase) & ~0xf;
writel(0, fbi->regbase);
while (readl(fbi->regbase + 0x38) & 0x10)
/* wait */;
writel((((info->var.hsync_len - 1) & 0x3f) << 26)
| ((info->var.left_margin & 0xff) << 18)
| (((info->var.xres - 1) & 0x3ff) << 8)
| (info->var.right_margin & 0xff), fbi->regbase + 0x4);
writel((((info->var.vsync_len - 1) & 0x3f) << 26)
| ((info->var.upper_margin & 0xff) << 18)
| (((info->var.yres - 1) & 0x3ff) << 8)
| (info->var.lower_margin & 0xff), fbi->regbase + 0x8);
writel((((info->var.yres - 1) & 0x400) << 2)
| ((info->var.xres - 1) & 0x400), fbi->regbase + 0x10);
writel(0x80000000, fbi->regbase + 0x20);
writel(control0 | (reg_bpp << 1) | 0x100, fbi->regbase);
return 0;
}
static inline u_int chan_to_field(u_int chan, struct fb_bitfield *bf)
{
chan &= 0xffff;
chan >>= 16 - bf->length;
return chan << bf->offset;
}
static int vt8500lcd_setcolreg(unsigned regno, unsigned red, unsigned green,
unsigned blue, unsigned transp,
struct fb_info *info) {
struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
int ret = 1;
unsigned int val;
if (regno >= 256)
return -EINVAL;
if (info->var.grayscale)
red = green = blue =
(19595 * red + 38470 * green + 7471 * blue) >> 16;
switch (fbi->fb.fix.visual) {
case FB_VISUAL_TRUECOLOR:
if (regno < 16) {
u32 *pal = fbi->fb.pseudo_palette;
val = chan_to_field(red, &fbi->fb.var.red);
val |= chan_to_field(green, &fbi->fb.var.green);
val |= chan_to_field(blue, &fbi->fb.var.blue);
pal[regno] = val;
ret = 0;
}
break;
case FB_VISUAL_STATIC_PSEUDOCOLOR:
case FB_VISUAL_PSEUDOCOLOR:
writew((red & 0xf800)
| ((green >> 5) & 0x7e0)
| ((blue >> 11) & 0x1f),
fbi->palette_cpu + sizeof(u16) * regno);
break;
}
return ret;
}
static int vt8500lcd_ioctl(struct fb_info *info, unsigned int cmd,
unsigned long arg)
{
int ret = 0;
struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
if (cmd == FBIO_WAITFORVSYNC) {
/* Unmask End of Frame interrupt */
writel(0xffffffff ^ (1 << 3), fbi->regbase + 0x3c);
ret = wait_event_interruptible_timeout(fbi->wait,
readl(fbi->regbase + 0x38) & (1 << 3), HZ / 10);
/* Mask back to reduce unwanted interrupt traffic */
writel(0xffffffff, fbi->regbase + 0x3c);
if (ret < 0)
return ret;
if (ret == 0)
return -ETIMEDOUT;
}
return ret;
}
static int vt8500lcd_pan_display(struct fb_var_screeninfo *var,
struct fb_info *info)
{
unsigned pixlen = info->fix.line_length / info->var.xres_virtual;
unsigned off = pixlen * var->xoffset
+ info->fix.line_length * var->yoffset;
struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
writel((1 << 31)
| (((info->var.xres_virtual - info->var.xres) * pixlen / 4) << 20)
| (off >> 2), fbi->regbase + 0x20);
return 0;
}
/*
* vt8500lcd_blank():
* Blank the display by setting all palette values to zero. Note,
* True Color modes do not really use the palette, so this will not
* blank the display in all modes.
*/
static int vt8500lcd_blank(int blank, struct fb_info *info)
{
int i;
switch (blank) {
case FB_BLANK_POWERDOWN:
case FB_BLANK_VSYNC_SUSPEND:
case FB_BLANK_HSYNC_SUSPEND:
case FB_BLANK_NORMAL:
if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR ||
info->fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR)
for (i = 0; i < 256; i++)
vt8500lcd_setcolreg(i, 0, 0, 0, 0, info);
fallthrough;
case FB_BLANK_UNBLANK:
if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR ||
info->fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR)
fb_set_cmap(&info->cmap, info);
}
return 0;
}
static const struct fb_ops vt8500lcd_ops = {
.owner = THIS_MODULE,
.fb_set_par = vt8500lcd_set_par,
.fb_setcolreg = vt8500lcd_setcolreg,
.fb_fillrect = wmt_ge_fillrect,
.fb_copyarea = wmt_ge_copyarea,
.fb_imageblit = sys_imageblit,
.fb_sync = wmt_ge_sync,
.fb_ioctl = vt8500lcd_ioctl,
.fb_pan_display = vt8500lcd_pan_display,
.fb_blank = vt8500lcd_blank,
};
static irqreturn_t vt8500lcd_handle_irq(int irq, void *dev_id)
{
struct vt8500lcd_info *fbi = dev_id;
if (readl(fbi->regbase + 0x38) & (1 << 3))
wake_up_interruptible(&fbi->wait);
writel(0xffffffff, fbi->regbase + 0x38);
return IRQ_HANDLED;
}
static int vt8500lcd_probe(struct platform_device *pdev)
{
struct vt8500lcd_info *fbi;
struct resource *res;
struct display_timings *disp_timing;
void *addr;
int irq, ret;
struct fb_videomode of_mode;
u32 bpp;
dma_addr_t fb_mem_phys;
unsigned long fb_mem_len;
void *fb_mem_virt;
ret = -ENOMEM;
fbi = NULL;
fbi = devm_kzalloc(&pdev->dev, sizeof(struct vt8500lcd_info)
+ sizeof(u32) * 16, GFP_KERNEL);
if (!fbi)
return -ENOMEM;
strcpy(fbi->fb.fix.id, "VT8500 LCD");
fbi->fb.fix.type = FB_TYPE_PACKED_PIXELS;
fbi->fb.fix.xpanstep = 0;
fbi->fb.fix.ypanstep = 1;
fbi->fb.fix.ywrapstep = 0;
fbi->fb.fix.accel = FB_ACCEL_NONE;
fbi->fb.var.nonstd = 0;
fbi->fb.var.activate = FB_ACTIVATE_NOW;
fbi->fb.var.height = -1;
fbi->fb.var.width = -1;
fbi->fb.var.vmode = FB_VMODE_NONINTERLACED;
fbi->fb.fbops = &vt8500lcd_ops;
fbi->fb.flags = FBINFO_HWACCEL_COPYAREA
| FBINFO_HWACCEL_FILLRECT
| FBINFO_HWACCEL_YPAN
| FBINFO_VIRTFB
| FBINFO_PARTIAL_PAN_OK;
fbi->fb.node = -1;
addr = fbi;
addr = addr + sizeof(struct vt8500lcd_info);
fbi->fb.pseudo_palette = addr;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (res == NULL) {
dev_err(&pdev->dev, "no I/O memory resource defined\n");
return -ENODEV;
}
res = request_mem_region(res->start, resource_size(res), "vt8500lcd");
if (res == NULL) {
dev_err(&pdev->dev, "failed to request I/O memory\n");
return -EBUSY;
}
fbi->regbase = ioremap(res->start, resource_size(res));
if (fbi->regbase == NULL) {
dev_err(&pdev->dev, "failed to map I/O memory\n");
ret = -EBUSY;
goto failed_free_res;
}
disp_timing = of_get_display_timings(pdev->dev.of_node);
if (!disp_timing) {
ret = -EINVAL;
goto failed_free_io;
}
ret = of_get_fb_videomode(pdev->dev.of_node, &of_mode,
OF_USE_NATIVE_MODE);
if (ret)
goto failed_free_io;
ret = of_property_read_u32(pdev->dev.of_node, "bits-per-pixel", &bpp);
if (ret)
goto failed_free_io;
/* try allocating the framebuffer */
fb_mem_len = of_mode.xres * of_mode.yres * 2 * (bpp / 8);
fb_mem_virt = dma_alloc_coherent(&pdev->dev, fb_mem_len, &fb_mem_phys,
GFP_KERNEL);
if (!fb_mem_virt) {
pr_err("%s: Failed to allocate framebuffer\n", __func__);
ret = -ENOMEM;
goto failed_free_io;
}
fbi->fb.fix.smem_start = fb_mem_phys;
fbi->fb.fix.smem_len = fb_mem_len;
fbi->fb.screen_base = fb_mem_virt;
fbi->palette_size = PAGE_ALIGN(512);
fbi->palette_cpu = dma_alloc_coherent(&pdev->dev,
fbi->palette_size,
&fbi->palette_phys,
GFP_KERNEL);
if (fbi->palette_cpu == NULL) {
dev_err(&pdev->dev, "Failed to allocate palette buffer\n");
ret = -ENOMEM;
goto failed_free_io;
}
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
dev_err(&pdev->dev, "no IRQ defined\n");
ret = -ENODEV;
goto failed_free_palette;
}
ret = request_irq(irq, vt8500lcd_handle_irq, 0, "LCD", fbi);
if (ret) {
dev_err(&pdev->dev, "request_irq failed: %d\n", ret);
ret = -EBUSY;
goto failed_free_palette;
}
init_waitqueue_head(&fbi->wait);
if (fb_alloc_cmap(&fbi->fb.cmap, 256, 0) < 0) {
dev_err(&pdev->dev, "Failed to allocate color map\n");
ret = -ENOMEM;
goto failed_free_irq;
}
fb_videomode_to_var(&fbi->fb.var, &of_mode);
fbi->fb.var.xres_virtual = of_mode.xres;
fbi->fb.var.yres_virtual = of_mode.yres * 2;
fbi->fb.var.bits_per_pixel = bpp;
ret = vt8500lcd_set_par(&fbi->fb);
if (ret) {
dev_err(&pdev->dev, "Failed to set parameters\n");
goto failed_free_cmap;
}
writel(fbi->fb.fix.smem_start >> 22, fbi->regbase + 0x1c);
writel((fbi->palette_phys & 0xfffffe00) | 1, fbi->regbase + 0x18);
platform_set_drvdata(pdev, fbi);
ret = register_framebuffer(&fbi->fb);
if (ret < 0) {
dev_err(&pdev->dev,
"Failed to register framebuffer device: %d\n", ret);
goto failed_free_cmap;
}
/*
* Ok, now enable the LCD controller
*/
writel(readl(fbi->regbase) | 1, fbi->regbase);
return 0;
failed_free_cmap:
if (fbi->fb.cmap.len)
fb_dealloc_cmap(&fbi->fb.cmap);
failed_free_irq:
free_irq(irq, fbi);
failed_free_palette:
dma_free_coherent(&pdev->dev, fbi->palette_size,
fbi->palette_cpu, fbi->palette_phys);
failed_free_io:
iounmap(fbi->regbase);
failed_free_res:
release_mem_region(res->start, resource_size(res));
return ret;
}
static void vt8500lcd_remove(struct platform_device *pdev)
{
struct vt8500lcd_info *fbi = platform_get_drvdata(pdev);
struct resource *res;
int irq;
unregister_framebuffer(&fbi->fb);
writel(0, fbi->regbase);
if (fbi->fb.cmap.len)
fb_dealloc_cmap(&fbi->fb.cmap);
irq = platform_get_irq(pdev, 0);
free_irq(irq, fbi);
dma_free_coherent(&pdev->dev, fbi->palette_size,
fbi->palette_cpu, fbi->palette_phys);
iounmap(fbi->regbase);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
release_mem_region(res->start, resource_size(res));
}
static const struct of_device_id via_dt_ids[] = {
{ .compatible = "via,vt8500-fb", },
{}
};
static struct platform_driver vt8500lcd_driver = {
.probe = vt8500lcd_probe,
.remove_new = vt8500lcd_remove,
.driver = {
.name = "vt8500-lcd",
.of_match_table = of_match_ptr(via_dt_ids),
},
};
module_platform_driver(vt8500lcd_driver);
MODULE_AUTHOR("Alexey Charkov <alchark@gmail.com>");
MODULE_DESCRIPTION("LCD controller driver for VIA VT8500");
MODULE_LICENSE("GPL v2");
MODULE_DEVICE_TABLE(of, via_dt_ids);