staging: fbtft: do not allocate huge txbuf

txbuflen can be set to arbitrary value by user and it is also set
automagically to the maximum transfer size of the SPI master controller.

Do not allocate the buffer when larger than vmem. When my SPI master
controller reports maximum transfer size 16M the probe of fbtft fails.

Signed-off-by: Michal Suchanek <hramrach@gmail.com>
Acked-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Michal Suchanek 2016-06-09 15:08:42 +00:00 committed by Greg Kroah-Hartman
parent d2805d7fff
commit 175f5a4130

View file

@ -820,6 +820,8 @@ struct fb_info *fbtft_framebuffer_alloc(struct fbtft_display *display,
/* Transmit buffer */
if (txbuflen == -1)
txbuflen = vmem_size + 2; /* add in case startbyte is used */
if (txbuflen >= vmem_size + 2)
txbuflen = 0;
#ifdef __LITTLE_ENDIAN
if ((!txbuflen) && (bpp > 8))