control display with fbtft modules - c

Question

I would like to swap upside part and lower part in the display.
like this
| 1 | to | 2 |
| 2 | to | 1 | upper half and lower half will be changed
so I have edited fbtft source (https://github.com/notro/fbtft/wiki/How-it-works, https://github.com/notro/fbtft)
I thought It is possible if I write the changed pixel value( pointer to current pixel value + half size ) in video memory when I send the data to 8 bit bus
my LCD is 240 X 320 resolution using SPI-8bit. device name is adafruit22a , driver name is ili9340.
this is the source I edited
first, in fbtft-core.c
void fbtft_update_display(struct fbtft_par *par, unsigned start_line, unsigned end_line)void fbtft_update_display(struct fbtft_par *par, unsigned start_line, unsigned end_line)
{
size_t offset, len;
struct timespec ts_start, ts_end, ts_fps, ts_duration;
long fps_ms, fps_us, duration_ms, duration_us;
long fps, throughput;
bool timeit = false;
int ret = 0;
unsigned start_line_t; // changed start line( startline + half size (119))
if (unlikely(par->debug & (DEBUG_TIME_FIRST_UPDATE | DEBUG_TIME_EACH_UPDATE))) {
if ((par->debug & DEBUG_TIME_EACH_UPDATE) || \
((par->debug & DEBUG_TIME_FIRST_UPDATE) && !par->first_update_done)) {
getnstimeofday(&ts_start);
timeit = true;
}
}
/* Sanity checks */
if (start_line > end_line) {
dev_warn(par->info->device,
"%s: start_line=%u is larger than end_line=%u. Shouldn't happen, will do full display update\n",
__func__, start_line, end_line);
start_line = 0;
end_line = par->info->var.yres - 1;
}
if (start_line > par->info->var.yres - 1 || end_line > par->info->var.yres - 1) {
dev_warn(par->info->device,
"%s: start_line=%u or end_line=%u is larger than max=%d. Shouldn't happen, will do full display update\n",
__func__, start_line, end_line, par->info->var.yres - 1);
start_line = 0;
end_line = par->info->var.yres - 1;
}
fbtft_par_dbg(DEBUG_UPDATE_DISPLAY, par, "%s(start_line=%u, end_line=%u)\n",
__func__, start_line, end_line);
if (par->fbtftops.set_addr_win)
par->fbtftops.set_addr_win(par, 0, start_line,
par->info->var.xres-1, end_line);
start_line_t= (start_line + 119)%239;
//offset = start_line * par->info->fix.line_length;
offset = start_line_t * par->info->fix.line_length;
len = (end_line - start_line + 1) * par->info->fix.line_length;
ret = par->fbtftops.write_vmem(par, offset, len);
if (ret < 0)
dev_err(par->info->device,
"%s: write_vmem failed to update display buffer\n",
__func__);
if (unlikely(timeit)) {
getnstimeofday(&ts_end);
if (par->update_time.tv_nsec == 0 && par->update_time.tv_sec == 0) {
par->update_time.tv_sec = ts_start.tv_sec;
par->update_time.tv_nsec = ts_start.tv_nsec;
}
ts_fps = timespec_sub(ts_start, par->update_time);
par->update_time.tv_sec = ts_start.tv_sec;
par->update_time.tv_nsec = ts_start.tv_nsec;
fps_ms = (ts_fps.tv_sec * 1000) + ((ts_fps.tv_nsec / 1000000) % 1000);
fps_us = (ts_fps.tv_nsec / 1000) % 1000;
fps = fps_ms * 1000 + fps_us;
fps = fps ? 1000000 / fps : 0;
ts_duration = timespec_sub(ts_end, ts_start);
duration_ms = (ts_duration.tv_sec * 1000) + ((ts_duration.tv_nsec / 1000000) % 1000);
duration_us = (ts_duration.tv_nsec / 1000) % 1000;
throughput = duration_ms * 1000 + duration_us;
throughput = throughput ? (len * 1000) / throughput : 0;
throughput = throughput * 1000 / 1024;
dev_info(par->info->device,
"Display update: %ld kB/s (%ld.%.3ld ms), fps=%ld (%ld.%.3ld ms)\n",
throughput, duration_ms, duration_us,
fps, fps_ms, fps_us);
par->first_update_done = true;
}
}
I changed start_line to start_line_t to move upper half to lower half.
then I write data from start_line_t to length in vedio memory (frame memory)
this is writing from video memory to bus in fbtft-bus.c
#define HALF_OF_LCD 119
#define END_OF_LCD 239
/* 16 bit pixel over 8-bit databus */
int fbtft_write_vmem16_bus8(struct fbtft_par *par, size_t offset, size_t len)
{
u16 *vmem16;
u16 *txbuf16 = (u16 *)par->txbuf.buf;
size_t remain;
size_t to_copy;
size_t tx_array_size;
int i;
int ret = 0;
size_t startbyte_size = 0;
size_t start_offset=0
size_t end_offset=0;
u16 *endMem16;
fbtft_par_dbg(DEBUG_WRITE_VMEM, par, "%s(offset=%zu, len=%zu)\n",
__func__, offset, len);
end_offset= 239 * par->info->fix.line_length;
endMem16=(u16 *)(par->info->screen_base+ end_offset);
remain = len / 2;
vmem16 = (u16 *)(par->info->screen_base + offset);
if (par->gpio.dc != -1)
gpio_set_value(par->gpio.dc, 1);
/* non buffered write */
if (!par->txbuf.buf)
return par->fbtftops.write(par, vmem16, len);
/* buffered write */
tx_array_size = par->txbuf.len / 2;
if (par->startbyte) {
txbuf16 = (u16 *)(par->txbuf.buf + 1);
tx_array_size -= 2;
*(u8 *)(par->txbuf.buf) = par->startbyte | 0x2;
startbyte_size = 1;
}
while(remain)
{
to_copy = remain > tx_array_size ? tx_array_size : remain;
for (i = 0; i < to_copy; i++)
{
txbuf16[i] = cpu_to_be16(*vmem16);
++vmem16;
if(vmem16 == endMem16)
vmem16=(u16 *)(par->info->screen_base);
}
ret = par->fbtftops.write(par, par->txbuf.buf,
startbyte_size + to_copy * 2);
if (ret < 0)
return ret;
remain -= to_copy;
}
return ret;
}
in the code if pointer get reached end of video memory address ,
it moves to initial address in video memory address.( lower half should be written in upper half side).
the result is showing what I want like swapped half display
but the problem is that mouse moving and update display are so slow
even mouse is disappeared in upper half side.
I dont know what is wrong and how should I edit the part of source
I want to control display with frame buffer
anyone help me ? T^T