This patch adds a module parameter 'bitsperpixel' to adjust the colordepth of the framebuffer. All values >1 will result in memory map of the requested color depth. However only the MSB of each pixel will be sent to the device. The framebuffer identifies itself as a grayscale display with the specified depth.
Signed-off-by: Thomas Niederprüm <nied...@physik.uni-kl.de> --- drivers/video/fbdev/ssd1307fb.c | 25 ++++++++++++++++--------- 1 file changed, 16 insertions(+), 9 deletions(-) diff --git a/drivers/video/fbdev/ssd1307fb.c b/drivers/video/fbdev/ssd1307fb.c index 7c8e627..3cf4da1 100644 --- a/drivers/video/fbdev/ssd1307fb.c +++ b/drivers/video/fbdev/ssd1307fb.c @@ -44,6 +44,10 @@ #define SSD1307FB_SET_VCOMH 0xdb #define REFRASHRATE 1 +#define BITSPERPIXEL 1 + +static u_int bitsperpixel = BITSPERPIXEL; +module_param(bitsperpixel, uint, 0); static u_int refreshrate = REFRASHRATE; module_param(refreshrate, uint, 0); @@ -99,7 +103,8 @@ static struct fb_fix_screeninfo ssd1307fb_fix = { }; static struct fb_var_screeninfo ssd1307fb_var = { - .bits_per_pixel = 1, + .bits_per_pixel = BITSPERPIXEL, + .grayscale = 1, }; static struct ssd1307fb_array *ssd1307fb_alloc_array(u32 len, u8 type) @@ -194,10 +199,11 @@ static void ssd1307fb_update_display(struct ssd1307fb_par *par) array->data[array_idx] = 0; for (k = 0; k < 8; k++) { u32 page_length = par->width * i; - u32 index = page_length + (par->width * k + j) / 8; + u32 index = page_length * bitsperpixel + (par->width * k + j) * bitsperpixel / 8; u8 byte = *(vmem + index); - u8 bit = byte & (1 << (j % 8)); - bit = bit >> (j % 8); + u8 bit = byte & (((1 << (bitsperpixel))-1) << (j % 8/bitsperpixel)); + + bit = (bit >> (j % 8/bitsperpixel)) >> (bitsperpixel-1); array->data[array_idx] |= bit << k; } } @@ -536,7 +542,7 @@ static int ssd1307fb_probe(struct i2c_client *client, par->dclk_div = par->device_info->default_dclk_div; par->dclk_frq = par->device_info->default_dclk_frq; - vmem_size = par->width * par->height / 8; + vmem_size = par->width * par->height * bitsperpixel / 8; vmem = vzalloc(vmem_size); if (!vmem) { @@ -557,20 +563,21 @@ static int ssd1307fb_probe(struct i2c_client *client, info->fbops = &ssd1307fb_ops; info->fix = ssd1307fb_fix; - info->fix.line_length = par->width / 8; + info->fix.line_length = par->width * bitsperpixel / 8; info->fbdefio = ssd1307fb_defio; info->var = ssd1307fb_var; + info->var.bits_per_pixel = bitsperpixel; info->var.xres = par->width; info->var.xres_virtual = par->width; info->var.yres = par->height; info->var.yres_virtual = par->height; - info->var.red.length = 1; + info->var.red.length = bitsperpixel; info->var.red.offset = 0; - info->var.green.length = 1; + info->var.green.length = bitsperpixel; info->var.green.offset = 0; - info->var.blue.length = 1; + info->var.blue.length = bitsperpixel; info->var.blue.offset = 0; info->screen_base = (u8 __force __iomem *)vmem; -- 2.3.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/