redonkable
/
remarkable-linux
1
0
Fork 0
Code Releases Activity

ARM: fbdev-mxsfb: Add property to save display 

Add prevent-frying-pan property in device tree
to prevent the pan function from looping bad
data to the display. Without this fix, a SW
crash can potentially fry the eInk display.

This is only relevant for the zero-sugar
plattform by reMarkable AS.
pull/10/head
Lars Ivar Miljeteig 2019-08-05 17:50:51 +02:00 committed by Steinar Bakkemo
parent 85ff106cfb
commit dbc32384db
1 changed files with 15 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
drivers/video/fbdev/mxsfb.c
View File

@ -268,6 +268,8 @@ struct mxsfb_info {
#ifdef CONFIG_FB_MXC_OVERLAY
struct mxsfb_layer overlay;
#endif
bool prevent_frying_pan;
};
#define mxsfb_is_v3(host) (host->devdata->ipversion == 3)
@ -1145,18 +1147,20 @@ static int mxsfb_pan_display(struct fb_var_screeninfo *var,
ret = wait_for_completion_timeout(&host->flip_complete, HZ / 2);
/* Next frame will be the zero frame (last frame in buffer) by default. */
offset = fb_info->fix.line_length * (var->yres_virtual - var->yres);
writel(fb_info->fix.smem_start + offset,
host->base + host->devdata->next_buf);
if (!ret) {
dev_err(fb_info->device,
"mxs wait for pan flip timeout\n");
return -ETIMEDOUT;
ret = -ETIMEDOUT;
}
return 0;
if (host->prevent_frying_pan) {
/* Next frame will be the zero frame (last frame in buffer) by default. */
offset = fb_info->fix.line_length * (var->yres_virtual - var->yres);
writel(fb_info->fix.smem_start + offset,
host->base + host->devdata->next_buf);
}
return ret;
}
static int mxsfb_mmap(struct fb_info *info, struct vm_area_struct *vma)
@ -2332,6 +2336,10 @@ static int mxsfb_probe(struct platform_device *pdev)
mxsfb_overlay_init(host);
host->prevent_frying_pan = of_property_read_bool(pdev->dev.of_node, "prevent-frying-pan");
if (host->prevent_frying_pan)
dev_info(&pdev->dev, "Driver set to prevent frying pan mode\n");
#ifndef CONFIG_FB_IMX64_DEBUG
console_lock();
ret = fb_blank(fb_info, FB_BLANK_UNBLANK);