HID: picolcd: do not reallocate memory on depth change
Reallocating memory in depth change does not work well if some
userspace application has mmapped() the framebuffer as that mapping
does not get adjusted (thus application continues to write to old
buffer).
In addition doing deferred_io_cleanup() and init() inside of set_par()
tends to deadlock with fbcon's flashing cursor.
Avoid all this by allocating a buffer that can hold 8bpp framebuffer
and just use 1/8 of it while running at 1bpp.
Signed-off-by: Bruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/hid-picolcd.c b/drivers/hid/hid-picolcd.c
index dc19501..f720454 100644
--- a/drivers/hid/hid-picolcd.c
+++ b/drivers/hid/hid-picolcd.c
@@ -563,19 +563,18 @@
static int picolcd_set_par(struct fb_info *info)
{
struct picolcd_data *data = info->par;
- u8 *o_fb, *n_fb;
+ u8 *tmp_fb, *o_fb;
if (info->var.bits_per_pixel == data->fb_bpp)
return 0;
/* switch between 1/8 bit depths */
if (info->var.bits_per_pixel != 1 && info->var.bits_per_pixel != 8)
return -EINVAL;
- o_fb = data->fb_bitmap;
- n_fb = vmalloc(PICOLCDFB_SIZE*info->var.bits_per_pixel);
- if (!n_fb)
+ o_fb = data->fb_bitmap;
+ tmp_fb = kmalloc(PICOLCDFB_SIZE*info->var.bits_per_pixel, GFP_KERNEL);
+ if (!tmp_fb)
return -ENOMEM;
- fb_deferred_io_cleanup(info);
/* translate FB content to new bits-per-pixel */
if (info->var.bits_per_pixel == 1) {
int i, b;
@@ -585,24 +584,22 @@
p <<= 1;
p |= o_fb[i*8+b] ? 0x01 : 0x00;
}
+ tmp_fb[i] = p;
}
+ memcpy(o_fb, tmp_fb, PICOLCDFB_SIZE);
info->fix.visual = FB_VISUAL_MONO01;
info->fix.line_length = PICOLCDFB_WIDTH / 8;
} else {
int i;
+ memcpy(tmp_fb, o_fb, PICOLCDFB_SIZE);
for (i = 0; i < PICOLCDFB_SIZE * 8; i++)
- n_fb[i] = o_fb[i/8] & (0x01 << (7 - i % 8)) ? 0xff : 0x00;
- info->fix.visual = FB_VISUAL_TRUECOLOR;
+ o_fb[i] = tmp_fb[i/8] & (0x01 << (7 - i % 8)) ? 0xff : 0x00;
+ info->fix.visual = FB_VISUAL_DIRECTCOLOR;
info->fix.line_length = PICOLCDFB_WIDTH;
}
- data->fb_bitmap = n_fb;
+ kfree(tmp_fb);
data->fb_bpp = info->var.bits_per_pixel;
- info->screen_base = (char __force __iomem *)n_fb;
- info->fix.smem_start = (unsigned long)n_fb;
- info->fix.smem_len = PICOLCDFB_SIZE*data->fb_bpp;
- fb_deferred_io_init(info);
- vfree(o_fb);
return 0;
}
@@ -692,7 +689,7 @@
u8 *fb_bitmap = NULL;
u32 *palette;
- fb_bitmap = vmalloc(PICOLCDFB_SIZE*picolcdfb_var.bits_per_pixel);
+ fb_bitmap = vmalloc(PICOLCDFB_SIZE*8);
if (fb_bitmap == NULL) {
dev_err(dev, "can't get a free page for framebuffer\n");
goto err_nomem;
@@ -728,7 +725,7 @@
info->fbops = &picolcdfb_ops;
info->var = picolcdfb_var;
info->fix = picolcdfb_fix;
- info->fix.smem_len = PICOLCDFB_SIZE;
+ info->fix.smem_len = PICOLCDFB_SIZE*8;
info->fix.smem_start = (unsigned long)fb_bitmap;
info->par = data;
info->flags = FBINFO_FLAG_DEFAULT;