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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/video/fbdev/skeletonfb.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/video/fbdev/skeletonfb.c')
-rw-r--r--drivers/video/fbdev/skeletonfb.c1027
1 files changed, 1027 insertions, 0 deletions
diff --git a/drivers/video/fbdev/skeletonfb.c b/drivers/video/fbdev/skeletonfb.c
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+/*
+ * linux/drivers/video/skeletonfb.c -- Skeleton for a frame buffer device
+ *
+ * Modified to new api Jan 2001 by James Simmons (jsimmons@transvirtual.com)
+ *
+ * Created 28 Dec 1997 by Geert Uytterhoeven
+ *
+ *
+ * I have started rewriting this driver as a example of the upcoming new API
+ * The primary goal is to remove the console code from fbdev and place it
+ * into fbcon.c. This reduces the code and makes writing a new fbdev driver
+ * easy since the author doesn't need to worry about console internals. It
+ * also allows the ability to run fbdev without a console/tty system on top
+ * of it.
+ *
+ * First the roles of struct fb_info and struct display have changed. Struct
+ * display will go away. The way the new framebuffer console code will
+ * work is that it will act to translate data about the tty/console in
+ * struct vc_data to data in a device independent way in struct fb_info. Then
+ * various functions in struct fb_ops will be called to store the device
+ * dependent state in the par field in struct fb_info and to change the
+ * hardware to that state. This allows a very clean separation of the fbdev
+ * layer from the console layer. It also allows one to use fbdev on its own
+ * which is a bounus for embedded devices. The reason this approach works is
+ * for each framebuffer device when used as a tty/console device is allocated
+ * a set of virtual terminals to it. Only one virtual terminal can be active
+ * per framebuffer device. We already have all the data we need in struct
+ * vc_data so why store a bunch of colormaps and other fbdev specific data
+ * per virtual terminal.
+ *
+ * As you can see doing this makes the con parameter pretty much useless
+ * for struct fb_ops functions, as it should be. Also having struct
+ * fb_var_screeninfo and other data in fb_info pretty much eliminates the
+ * need for get_fix and get_var. Once all drivers use the fix, var, and cmap
+ * fbcon can be written around these fields. This will also eliminate the
+ * need to regenerate struct fb_var_screeninfo, struct fb_fix_screeninfo
+ * struct fb_cmap every time get_var, get_fix, get_cmap functions are called
+ * as many drivers do now.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file COPYING in the main directory of this archive for
+ * more details.
+ */
+
+#include <linux/aperture.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/fb.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+
+ /*
+ * This is just simple sample code.
+ *
+ * No warranty that it actually compiles.
+ * Even less warranty that it actually works :-)
+ */
+
+/*
+ * Driver data
+ */
+static char *mode_option;
+
+/*
+ * If your driver supports multiple boards, you should make the
+ * below data types arrays, or allocate them dynamically (using kmalloc()).
+ */
+
+/*
+ * This structure defines the hardware state of the graphics card. Normally
+ * you place this in a header file in linux/include/video. This file usually
+ * also includes register information. That allows other driver subsystems
+ * and userland applications the ability to use the same header file to
+ * avoid duplicate work and easy porting of software.
+ */
+struct xxx_par;
+
+/*
+ * Here we define the default structs fb_fix_screeninfo and fb_var_screeninfo
+ * if we don't use modedb. If we do use modedb see xxxfb_init how to use it
+ * to get a fb_var_screeninfo. Otherwise define a default var as well.
+ */
+static const struct fb_fix_screeninfo xxxfb_fix = {
+ .id = "FB's name",
+ .type = FB_TYPE_PACKED_PIXELS,
+ .visual = FB_VISUAL_PSEUDOCOLOR,
+ .xpanstep = 1,
+ .ypanstep = 1,
+ .ywrapstep = 1,
+ .accel = FB_ACCEL_NONE,
+};
+
+ /*
+ * Modern graphical hardware not only supports pipelines but some
+ * also support multiple monitors where each display can have
+ * its own unique data. In this case each display could be
+ * represented by a separate framebuffer device thus a separate
+ * struct fb_info. Now the struct xxx_par represents the graphics
+ * hardware state thus only one exist per card. In this case the
+ * struct xxx_par for each graphics card would be shared between
+ * every struct fb_info that represents a framebuffer on that card.
+ * This allows when one display changes it video resolution (info->var)
+ * the other displays know instantly. Each display can always be
+ * aware of the entire hardware state that affects it because they share
+ * the same xxx_par struct. The other side of the coin is multiple
+ * graphics cards that pass data around until it is finally displayed
+ * on one monitor. Such examples are the voodoo 1 cards and high end
+ * NUMA graphics servers. For this case we have a bunch of pars, each
+ * one that represents a graphics state, that belong to one struct
+ * fb_info. Their you would want to have *par point to a array of device
+ * states and have each struct fb_ops function deal with all those
+ * states. I hope this covers every possible hardware design. If not
+ * feel free to send your ideas at jsimmons@users.sf.net
+ */
+
+ /*
+ * If your driver supports multiple boards or it supports multiple
+ * framebuffers, you should make these arrays, or allocate them
+ * dynamically using framebuffer_alloc() and free them with
+ * framebuffer_release().
+ */
+static struct fb_info info;
+
+ /*
+ * Each one represents the state of the hardware. Most hardware have
+ * just one hardware state. These here represent the default state(s).
+ */
+static struct xxx_par __initdata current_par;
+
+/**
+ * xxxfb_open - Optional function. Called when the framebuffer is
+ * first accessed.
+ * @info: frame buffer structure that represents a single frame buffer
+ * @user: tell us if the userland (value=1) or the console is accessing
+ * the framebuffer.
+ *
+ * This function is the first function called in the framebuffer api.
+ * Usually you don't need to provide this function. The case where it
+ * is used is to change from a text mode hardware state to a graphics
+ * mode state.
+ *
+ * Returns negative errno on error, or zero on success.
+ */
+static int xxxfb_open(struct fb_info *info, int user)
+{
+ return 0;
+}
+
+/**
+ * xxxfb_release - Optional function. Called when the framebuffer
+ * device is closed.
+ * @info: frame buffer structure that represents a single frame buffer
+ * @user: tell us if the userland (value=1) or the console is accessing
+ * the framebuffer.
+ *
+ * Thus function is called when we close /dev/fb or the framebuffer
+ * console system is released. Usually you don't need this function.
+ * The case where it is usually used is to go from a graphics state
+ * to a text mode state.
+ *
+ * Returns negative errno on error, or zero on success.
+ */
+static int xxxfb_release(struct fb_info *info, int user)
+{
+ return 0;
+}
+
+/**
+ * xxxfb_check_var - Optional function. Validates a var passed in.
+ * @var: frame buffer variable screen structure
+ * @info: frame buffer structure that represents a single frame buffer
+ *
+ * Checks to see if the hardware supports the state requested by
+ * var passed in. This function does not alter the hardware state!!!
+ * This means the data stored in struct fb_info and struct xxx_par do
+ * not change. This includes the var inside of struct fb_info.
+ * Do NOT change these. This function can be called on its own if we
+ * intent to only test a mode and not actually set it. The stuff in
+ * modedb.c is a example of this. If the var passed in is slightly
+ * off by what the hardware can support then we alter the var PASSED in
+ * to what we can do.
+ *
+ * For values that are off, this function must round them _up_ to the
+ * next value that is supported by the hardware. If the value is
+ * greater than the highest value supported by the hardware, then this
+ * function must return -EINVAL.
+ *
+ * Exception to the above rule: Some drivers have a fixed mode, ie,
+ * the hardware is already set at boot up, and cannot be changed. In
+ * this case, it is more acceptable that this function just return
+ * a copy of the currently working var (info->var). Better is to not
+ * implement this function, as the upper layer will do the copying
+ * of the current var for you.
+ *
+ * Note: This is the only function where the contents of var can be
+ * freely adjusted after the driver has been registered. If you find
+ * that you have code outside of this function that alters the content
+ * of var, then you are doing something wrong. Note also that the
+ * contents of info->var must be left untouched at all times after
+ * driver registration.
+ *
+ * Returns negative errno on error, or zero on success.
+ */
+static int xxxfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
+{
+ /* ... */
+ return 0;
+}
+
+/**
+ * xxxfb_set_par - Optional function. Alters the hardware state.
+ * @info: frame buffer structure that represents a single frame buffer
+ *
+ * Using the fb_var_screeninfo in fb_info we set the resolution of the
+ * this particular framebuffer. This function alters the par AND the
+ * fb_fix_screeninfo stored in fb_info. It doesn't not alter var in
+ * fb_info since we are using that data. This means we depend on the
+ * data in var inside fb_info to be supported by the hardware.
+ *
+ * This function is also used to recover/restore the hardware to a
+ * known working state.
+ *
+ * xxxfb_check_var is always called before xxxfb_set_par to ensure that
+ * the contents of var is always valid.
+ *
+ * Again if you can't change the resolution you don't need this function.
+ *
+ * However, even if your hardware does not support mode changing,
+ * a set_par might be needed to at least initialize the hardware to
+ * a known working state, especially if it came back from another
+ * process that also modifies the same hardware, such as X.
+ *
+ * If this is the case, a combination such as the following should work:
+ *
+ * static int xxxfb_check_var(struct fb_var_screeninfo *var,
+ * struct fb_info *info)
+ * {
+ * *var = info->var;
+ * return 0;
+ * }
+ *
+ * static int xxxfb_set_par(struct fb_info *info)
+ * {
+ * init your hardware here
+ * }
+ *
+ * Returns negative errno on error, or zero on success.
+ */
+static int xxxfb_set_par(struct fb_info *info)
+{
+ struct xxx_par *par = info->par;
+ /* ... */
+ return 0;
+}
+
+/**
+ * xxxfb_setcolreg - Optional function. Sets a color register.
+ * @regno: Which register in the CLUT we are programming
+ * @red: The red value which can be up to 16 bits wide
+ * @green: The green value which can be up to 16 bits wide
+ * @blue: The blue value which can be up to 16 bits wide.
+ * @transp: If supported, the alpha value which can be up to 16 bits wide.
+ * @info: frame buffer info structure
+ *
+ * Set a single color register. The values supplied have a 16 bit
+ * magnitude which needs to be scaled in this function for the hardware.
+ * Things to take into consideration are how many color registers, if
+ * any, are supported with the current color visual. With truecolor mode
+ * no color palettes are supported. Here a pseudo palette is created
+ * which we store the value in pseudo_palette in struct fb_info. For
+ * pseudocolor mode we have a limited color palette. To deal with this
+ * we can program what color is displayed for a particular pixel value.
+ * DirectColor is similar in that we can program each color field. If
+ * we have a static colormap we don't need to implement this function.
+ *
+ * Returns negative errno on error, or zero on success.
+ */
+static int xxxfb_setcolreg(unsigned regno, unsigned red, unsigned green,
+ unsigned blue, unsigned transp,
+ struct fb_info *info)
+{
+ if (regno >= 256) /* no. of hw registers */
+ return -EINVAL;
+ /*
+ * Program hardware... do anything you want with transp
+ */
+
+ /* grayscale works only partially under directcolor */
+ if (info->var.grayscale) {
+ /* grayscale = 0.30*R + 0.59*G + 0.11*B */
+ red = green = blue = (red * 77 + green * 151 + blue * 28) >> 8;
+ }
+
+ /* Directcolor:
+ * var->{color}.offset contains start of bitfield
+ * var->{color}.length contains length of bitfield
+ * {hardwarespecific} contains width of DAC
+ * pseudo_palette[X] is programmed to (X << red.offset) |
+ * (X << green.offset) |
+ * (X << blue.offset)
+ * RAMDAC[X] is programmed to (red, green, blue)
+ * color depth = SUM(var->{color}.length)
+ *
+ * Pseudocolor:
+ * var->{color}.offset is 0 unless the palette index takes less than
+ * bits_per_pixel bits and is stored in the upper
+ * bits of the pixel value
+ * var->{color}.length is set so that 1 << length is the number of
+ * available palette entries
+ * pseudo_palette is not used
+ * RAMDAC[X] is programmed to (red, green, blue)
+ * color depth = var->{color}.length
+ *
+ * Static pseudocolor:
+ * same as Pseudocolor, but the RAMDAC is not programmed (read-only)
+ *
+ * Mono01/Mono10:
+ * Has only 2 values, black on white or white on black (fg on bg),
+ * var->{color}.offset is 0
+ * white = (1 << var->{color}.length) - 1, black = 0
+ * pseudo_palette is not used
+ * RAMDAC does not exist
+ * color depth is always 2
+ *
+ * Truecolor:
+ * does not use RAMDAC (usually has 3 of them).
+ * var->{color}.offset contains start of bitfield
+ * var->{color}.length contains length of bitfield
+ * pseudo_palette is programmed to (red << red.offset) |
+ * (green << green.offset) |
+ * (blue << blue.offset) |
+ * (transp << transp.offset)
+ * RAMDAC does not exist
+ * color depth = SUM(var->{color}.length})
+ *
+ * The color depth is used by fbcon for choosing the logo and also
+ * for color palette transformation if color depth < 4
+ *
+ * As can be seen from the above, the field bits_per_pixel is _NOT_
+ * a criteria for describing the color visual.
+ *
+ * A common mistake is assuming that bits_per_pixel <= 8 is pseudocolor,
+ * and higher than that, true/directcolor. This is incorrect, one needs
+ * to look at the fix->visual.
+ *
+ * Another common mistake is using bits_per_pixel to calculate the color
+ * depth. The bits_per_pixel field does not directly translate to color
+ * depth. You have to compute for the color depth (using the color
+ * bitfields) and fix->visual as seen above.
+ */
+
+ /*
+ * This is the point where the color is converted to something that
+ * is acceptable by the hardware.
+ */
+#define CNVT_TOHW(val,width) ((((val)<<(width))+0x7FFF-(val))>>16)
+ red = CNVT_TOHW(red, info->var.red.length);
+ green = CNVT_TOHW(green, info->var.green.length);
+ blue = CNVT_TOHW(blue, info->var.blue.length);
+ transp = CNVT_TOHW(transp, info->var.transp.length);
+#undef CNVT_TOHW
+ /*
+ * This is the point where the function feeds the color to the hardware
+ * palette after converting the colors to something acceptable by
+ * the hardware. Note, only FB_VISUAL_DIRECTCOLOR and
+ * FB_VISUAL_PSEUDOCOLOR visuals need to write to the hardware palette.
+ * If you have code that writes to the hardware CLUT, and it's not
+ * any of the above visuals, then you are doing something wrong.
+ */
+ if (info->fix.visual == FB_VISUAL_DIRECTCOLOR ||
+ info->fix.visual == FB_VISUAL_TRUECOLOR)
+ write_{red|green|blue|transp}_to_clut();
+
+ /* This is the point were you need to fill up the contents of
+ * info->pseudo_palette. This structure is used _only_ by fbcon, thus
+ * it only contains 16 entries to match the number of colors supported
+ * by the console. The pseudo_palette is used only if the visual is
+ * in directcolor or truecolor mode. With other visuals, the
+ * pseudo_palette is not used. (This might change in the future.)
+ *
+ * The contents of the pseudo_palette is in raw pixel format. Ie, each
+ * entry can be written directly to the framebuffer without any conversion.
+ * The pseudo_palette is (void *). However, if using the generic
+ * drawing functions (cfb_imageblit, cfb_fillrect), the pseudo_palette
+ * must be casted to (u32 *) _regardless_ of the bits per pixel. If the
+ * driver is using its own drawing functions, then it can use whatever
+ * size it wants.
+ */
+ if (info->fix.visual == FB_VISUAL_TRUECOLOR ||
+ info->fix.visual == FB_VISUAL_DIRECTCOLOR) {
+ u32 v;
+
+ if (regno >= 16)
+ return -EINVAL;
+
+ v = (red << info->var.red.offset) |
+ (green << info->var.green.offset) |
+ (blue << info->var.blue.offset) |
+ (transp << info->var.transp.offset);
+
+ ((u32*)(info->pseudo_palette))[regno] = v;
+ }
+
+ /* ... */
+ return 0;
+}
+
+/**
+ * xxxfb_pan_display - NOT a required function. Pans the display.
+ * @var: frame buffer variable screen structure
+ * @info: frame buffer structure that represents a single frame buffer
+ *
+ * Pan (or wrap, depending on the `vmode' field) the display using the
+ * `xoffset' and `yoffset' fields of the `var' structure.
+ * If the values don't fit, return -EINVAL.
+ *
+ * Returns negative errno on error, or zero on success.
+ */
+static int xxxfb_pan_display(struct fb_var_screeninfo *var,
+ struct fb_info *info)
+{
+ /*
+ * If your hardware does not support panning, _do_ _not_ implement this
+ * function. Creating a dummy function will just confuse user apps.
+ */
+
+ /*
+ * Note that even if this function is fully functional, a setting of
+ * 0 in both xpanstep and ypanstep means that this function will never
+ * get called.
+ */
+
+ /* ... */
+ return 0;
+}
+
+/**
+ * xxxfb_blank - NOT a required function. Blanks the display.
+ * @blank_mode: the blank mode we want.
+ * @info: frame buffer structure that represents a single frame buffer
+ *
+ * Blank the screen if blank_mode != FB_BLANK_UNBLANK, else unblank.
+ * Return 0 if blanking succeeded, != 0 if un-/blanking failed due to
+ * e.g. a video mode which doesn't support it.
+ *
+ * Implements VESA suspend and powerdown modes on hardware that supports
+ * disabling hsync/vsync:
+ *
+ * FB_BLANK_NORMAL = display is blanked, syncs are on.
+ * FB_BLANK_HSYNC_SUSPEND = hsync off
+ * FB_BLANK_VSYNC_SUSPEND = vsync off
+ * FB_BLANK_POWERDOWN = hsync and vsync off
+ *
+ * If implementing this function, at least support FB_BLANK_UNBLANK.
+ * Return !0 for any modes that are unimplemented.
+ *
+ */
+static int xxxfb_blank(int blank_mode, struct fb_info *info)
+{
+ /* ... */
+ return 0;
+}
+
+/* ------------ Accelerated Functions --------------------- */
+
+/*
+ * We provide our own functions if we have hardware acceleration
+ * or non packed pixel format layouts. If we have no hardware
+ * acceleration, we can use a generic unaccelerated function. If using
+ * a pack pixel format just use the functions in cfb_*.c. Each file
+ * has one of the three different accel functions we support.
+ */
+
+/**
+ * xxxfb_fillrect - REQUIRED function. Can use generic routines if
+ * non acclerated hardware and packed pixel based.
+ * Draws a rectangle on the screen.
+ *
+ * @info: frame buffer structure that represents a single frame buffer
+ * @region: The structure representing the rectangular region we
+ * wish to draw to.
+ *
+ * This drawing operation places/removes a retangle on the screen
+ * depending on the rastering operation with the value of color which
+ * is in the current color depth format.
+ */
+void xxxfb_fillrect(struct fb_info *p, const struct fb_fillrect *region)
+{
+/* Meaning of struct fb_fillrect
+ *
+ * @dx: The x and y corrdinates of the upper left hand corner of the
+ * @dy: area we want to draw to.
+ * @width: How wide the rectangle is we want to draw.
+ * @height: How tall the rectangle is we want to draw.
+ * @color: The color to fill in the rectangle with.
+ * @rop: The raster operation. We can draw the rectangle with a COPY
+ * of XOR which provides erasing effect.
+ */
+}
+
+/**
+ * xxxfb_copyarea - REQUIRED function. Can use generic routines if
+ * non acclerated hardware and packed pixel based.
+ * Copies one area of the screen to another area.
+ *
+ * @info: frame buffer structure that represents a single frame buffer
+ * @area: Structure providing the data to copy the framebuffer contents
+ * from one region to another.
+ *
+ * This drawing operation copies a rectangular area from one area of the
+ * screen to another area.
+ */
+void xxxfb_copyarea(struct fb_info *p, const struct fb_copyarea *area)
+{
+/*
+ * @dx: The x and y coordinates of the upper left hand corner of the
+ * @dy: destination area on the screen.
+ * @width: How wide the rectangle is we want to copy.
+ * @height: How tall the rectangle is we want to copy.
+ * @sx: The x and y coordinates of the upper left hand corner of the
+ * @sy: source area on the screen.
+ */
+}
+
+
+/**
+ * xxxfb_imageblit - REQUIRED function. Can use generic routines if
+ * non acclerated hardware and packed pixel based.
+ * Copies a image from system memory to the screen.
+ *
+ * @info: frame buffer structure that represents a single frame buffer
+ * @image: structure defining the image.
+ *
+ * This drawing operation draws a image on the screen. It can be a
+ * mono image (needed for font handling) or a color image (needed for
+ * tux).
+ */
+void xxxfb_imageblit(struct fb_info *p, const struct fb_image *image)
+{
+/*
+ * @dx: The x and y coordinates of the upper left hand corner of the
+ * @dy: destination area to place the image on the screen.
+ * @width: How wide the image is we want to copy.
+ * @height: How tall the image is we want to copy.
+ * @fg_color: For mono bitmap images this is color data for
+ * @bg_color: the foreground and background of the image to
+ * write directly to the frmaebuffer.
+ * @depth: How many bits represent a single pixel for this image.
+ * @data: The actual data used to construct the image on the display.
+ * @cmap: The colormap used for color images.
+ */
+
+/*
+ * The generic function, cfb_imageblit, expects that the bitmap scanlines are
+ * padded to the next byte. Most hardware accelerators may require padding to
+ * the next u16 or the next u32. If that is the case, the driver can specify
+ * this by setting info->pixmap.scan_align = 2 or 4. See a more
+ * comprehensive description of the pixmap below.
+ */
+}
+
+/**
+ * xxxfb_cursor - OPTIONAL. If your hardware lacks support
+ * for a cursor, leave this field NULL.
+ *
+ * @info: frame buffer structure that represents a single frame buffer
+ * @cursor: structure defining the cursor to draw.
+ *
+ * This operation is used to set or alter the properities of the
+ * cursor.
+ *
+ * Returns negative errno on error, or zero on success.
+ */
+int xxxfb_cursor(struct fb_info *info, struct fb_cursor *cursor)
+{
+/*
+ * @set: Which fields we are altering in struct fb_cursor
+ * @enable: Disable or enable the cursor
+ * @rop: The bit operation we want to do.
+ * @mask: This is the cursor mask bitmap.
+ * @dest: A image of the area we are going to display the cursor.
+ * Used internally by the driver.
+ * @hot: The hot spot.
+ * @image: The actual data for the cursor image.
+ *
+ * NOTES ON FLAGS (cursor->set):
+ *
+ * FB_CUR_SETIMAGE - the cursor image has changed (cursor->image.data)
+ * FB_CUR_SETPOS - the cursor position has changed (cursor->image.dx|dy)
+ * FB_CUR_SETHOT - the cursor hot spot has changed (cursor->hot.dx|dy)
+ * FB_CUR_SETCMAP - the cursor colors has changed (cursor->fg_color|bg_color)
+ * FB_CUR_SETSHAPE - the cursor bitmask has changed (cursor->mask)
+ * FB_CUR_SETSIZE - the cursor size has changed (cursor->width|height)
+ * FB_CUR_SETALL - everything has changed
+ *
+ * NOTES ON ROPs (cursor->rop, Raster Operation)
+ *
+ * ROP_XOR - cursor->image.data XOR cursor->mask
+ * ROP_COPY - curosr->image.data AND cursor->mask
+ *
+ * OTHER NOTES:
+ *
+ * - fbcon only supports a 2-color cursor (cursor->image.depth = 1)
+ * - The fb_cursor structure, @cursor, _will_ always contain valid
+ * fields, whether any particular bitfields in cursor->set is set
+ * or not.
+ */
+}
+
+/**
+ * xxxfb_sync - NOT a required function. Normally the accel engine
+ * for a graphics card take a specific amount of time.
+ * Often we have to wait for the accelerator to finish
+ * its operation before we can write to the framebuffer
+ * so we can have consistent display output.
+ *
+ * @info: frame buffer structure that represents a single frame buffer
+ *
+ * If the driver has implemented its own hardware-based drawing function,
+ * implementing this function is highly recommended.
+ */
+int xxxfb_sync(struct fb_info *info)
+{
+ return 0;
+}
+
+ /*
+ * Frame buffer operations
+ */
+
+static const struct fb_ops xxxfb_ops = {
+ .owner = THIS_MODULE,
+ .fb_open = xxxfb_open,
+ .fb_read = xxxfb_read,
+ .fb_write = xxxfb_write,
+ .fb_release = xxxfb_release,
+ .fb_check_var = xxxfb_check_var,
+ .fb_set_par = xxxfb_set_par,
+ .fb_setcolreg = xxxfb_setcolreg,
+ .fb_blank = xxxfb_blank,
+ .fb_pan_display = xxxfb_pan_display,
+ .fb_fillrect = xxxfb_fillrect, /* Needed !!! */
+ .fb_copyarea = xxxfb_copyarea, /* Needed !!! */
+ .fb_imageblit = xxxfb_imageblit, /* Needed !!! */
+ .fb_cursor = xxxfb_cursor, /* Optional !!! */
+ .fb_sync = xxxfb_sync,
+ .fb_ioctl = xxxfb_ioctl,
+ .fb_mmap = xxxfb_mmap,
+};
+
+/* ------------------------------------------------------------------------- */
+
+ /*
+ * Initialization
+ */
+
+/* static int __init xxfb_probe (struct platform_device *pdev) -- for platform devs */
+static int xxxfb_probe(struct pci_dev *dev, const struct pci_device_id *ent)
+{
+ struct fb_info *info;
+ struct xxx_par *par;
+ struct device *device = &dev->dev; /* or &pdev->dev */
+ int cmap_len, retval;
+
+ /*
+ * Remove firmware-based drivers that create resource conflicts.
+ */
+ retval = aperture_remove_conflicting_pci_devices(pdev, "xxxfb");
+ if (retval)
+ return retval;
+
+ /*
+ * Dynamically allocate info and par
+ */
+ info = framebuffer_alloc(sizeof(struct xxx_par), device);
+
+ if (!info) {
+ /* goto error path */
+ }
+
+ par = info->par;
+
+ /*
+ * Here we set the screen_base to the virtual memory address
+ * for the framebuffer. Usually we obtain the resource address
+ * from the bus layer and then translate it to virtual memory
+ * space via ioremap. Consult ioport.h.
+ */
+ info->screen_base = framebuffer_virtual_memory;
+ info->fbops = &xxxfb_ops;
+ info->fix = xxxfb_fix;
+ info->pseudo_palette = pseudo_palette; /* The pseudopalette is an
+ * 16-member array
+ */
+ /*
+ * Set up flags to indicate what sort of acceleration your
+ * driver can provide (pan/wrap/copyarea/etc.) and whether it
+ * is a module -- see FBINFO_* in include/linux/fb.h
+ *
+ * If your hardware can support any of the hardware accelerated functions
+ * fbcon performance will improve if info->flags is set properly.
+ *
+ * FBINFO_HWACCEL_COPYAREA - hardware moves
+ * FBINFO_HWACCEL_FILLRECT - hardware fills
+ * FBINFO_HWACCEL_IMAGEBLIT - hardware mono->color expansion
+ * FBINFO_HWACCEL_YPAN - hardware can pan display in y-axis
+ * FBINFO_HWACCEL_YWRAP - hardware can wrap display in y-axis
+ * FBINFO_HWACCEL_DISABLED - supports hardware accels, but disabled
+ * FBINFO_READS_FAST - if set, prefer moves over mono->color expansion
+ * FBINFO_MISC_TILEBLITTING - hardware can do tile blits
+ *
+ * NOTE: These are for fbcon use only.
+ */
+ info->flags = FBINFO_DEFAULT;
+
+/********************* This stage is optional ******************************/
+ /*
+ * The struct pixmap is a scratch pad for the drawing functions. This
+ * is where the monochrome bitmap is constructed by the higher layers
+ * and then passed to the accelerator. For drivers that uses
+ * cfb_imageblit, you can skip this part. For those that have a more
+ * rigorous requirement, this stage is needed
+ */
+
+ /* PIXMAP_SIZE should be small enough to optimize drawing, but not
+ * large enough that memory is wasted. A safe size is
+ * (max_xres * max_font_height/8). max_xres is driver dependent,
+ * max_font_height is 32.
+ */
+ info->pixmap.addr = kmalloc(PIXMAP_SIZE, GFP_KERNEL);
+ if (!info->pixmap.addr) {
+ /* goto error */
+ }
+
+ info->pixmap.size = PIXMAP_SIZE;
+
+ /*
+ * FB_PIXMAP_SYSTEM - memory is in system ram
+ * FB_PIXMAP_IO - memory is iomapped
+ * FB_PIXMAP_SYNC - if set, will call fb_sync() per access to pixmap,
+ * usually if FB_PIXMAP_IO is set.
+ *
+ * Currently, FB_PIXMAP_IO is unimplemented.
+ */
+ info->pixmap.flags = FB_PIXMAP_SYSTEM;
+
+ /*
+ * scan_align is the number of padding for each scanline. It is in bytes.
+ * Thus for accelerators that need padding to the next u32, put 4 here.
+ */
+ info->pixmap.scan_align = 4;
+
+ /*
+ * buf_align is the amount to be padded for the buffer. For example,
+ * the i810fb needs a scan_align of 2 but expects it to be fed with
+ * dwords, so a buf_align = 4 is required.
+ */
+ info->pixmap.buf_align = 4;
+
+ /* access_align is how many bits can be accessed from the framebuffer
+ * ie. some epson cards allow 16-bit access only. Most drivers will
+ * be safe with u32 here.
+ *
+ * NOTE: This field is currently unused.
+ */
+ info->pixmap.access_align = 32;
+/***************************** End optional stage ***************************/
+
+ /*
+ * This should give a reasonable default video mode. The following is
+ * done when we can set a video mode.
+ */
+ if (!mode_option)
+ mode_option = "640x480@60";
+
+ retval = fb_find_mode(&info->var, info, mode_option, NULL, 0, NULL, 8);
+
+ if (!retval || retval == 4)
+ return -EINVAL;
+
+ /* This has to be done! */
+ if (fb_alloc_cmap(&info->cmap, cmap_len, 0))
+ return -ENOMEM;
+
+ /*
+ * The following is done in the case of having hardware with a static
+ * mode. If we are setting the mode ourselves we don't call this.
+ */
+ info->var = xxxfb_var;
+
+ /*
+ * For drivers that can...
+ */
+ xxxfb_check_var(&info->var, info);
+
+ /*
+ * Does a call to fb_set_par() before register_framebuffer needed? This
+ * will depend on you and the hardware. If you are sure that your driver
+ * is the only device in the system, a call to fb_set_par() is safe.
+ *
+ * Hardware in x86 systems has a VGA core. Calling set_par() at this
+ * point will corrupt the VGA console, so it might be safer to skip a
+ * call to set_par here and just allow fbcon to do it for you.
+ */
+ /* xxxfb_set_par(info); */
+
+ if (register_framebuffer(info) < 0) {
+ fb_dealloc_cmap(&info->cmap);
+ return -EINVAL;
+ }
+ fb_info(info, "%s frame buffer device\n", info->fix.id);
+ pci_set_drvdata(dev, info); /* or platform_set_drvdata(pdev, info) */
+ return 0;
+}
+
+ /*
+ * Cleanup
+ */
+/* static void xxxfb_remove(struct platform_device *pdev) */
+static void xxxfb_remove(struct pci_dev *dev)
+{
+ struct fb_info *info = pci_get_drvdata(dev);
+ /* or platform_get_drvdata(pdev); */
+
+ if (info) {
+ unregister_framebuffer(info);
+ fb_dealloc_cmap(&info->cmap);
+ /* ... */
+ framebuffer_release(info);
+ }
+}
+
+#ifdef CONFIG_PCI
+#ifdef CONFIG_PM
+/**
+ * xxxfb_suspend - Optional but recommended function. Suspend the device.
+ * @dev: PCI device
+ * @msg: the suspend event code.
+ *
+ * See Documentation/driver-api/pm/devices.rst for more information
+ */
+static int xxxfb_suspend(struct device *dev)
+{
+ struct fb_info *info = dev_get_drvdata(dev);
+ struct xxxfb_par *par = info->par;
+
+ /* suspend here */
+ return 0;
+}
+
+/**
+ * xxxfb_resume - Optional but recommended function. Resume the device.
+ * @dev: PCI device
+ *
+ * See Documentation/driver-api/pm/devices.rst for more information
+ */
+static int xxxfb_resume(struct device *dev)
+{
+ struct fb_info *info = dev_get_drvdata(dev);
+ struct xxxfb_par *par = info->par;
+
+ /* resume here */
+ return 0;
+}
+#else
+#define xxxfb_suspend NULL
+#define xxxfb_resume NULL
+#endif /* CONFIG_PM */
+
+static const struct pci_device_id xxxfb_id_table[] = {
+ { PCI_VENDOR_ID_XXX, PCI_DEVICE_ID_XXX,
+ PCI_ANY_ID, PCI_ANY_ID, PCI_BASE_CLASS_DISPLAY << 16,
+ PCI_CLASS_MASK, 0 },
+ { 0, }
+};
+
+static SIMPLE_DEV_PM_OPS(xxxfb_pm_ops, xxxfb_suspend, xxxfb_resume);
+
+/* For PCI drivers */
+static struct pci_driver xxxfb_driver = {
+ .name = "xxxfb",
+ .id_table = xxxfb_id_table,
+ .probe = xxxfb_probe,
+ .remove = xxxfb_remove,
+ .driver.pm = xxxfb_pm_ops, /* optional but recommended */
+};
+
+MODULE_DEVICE_TABLE(pci, xxxfb_id_table);
+
+static int __init xxxfb_init(void)
+{
+ /*
+ * For kernel boot options (in 'video=xxxfb:<options>' format)
+ */
+#ifndef MODULE
+ char *option = NULL;
+
+ if (fb_get_options("xxxfb", &option))
+ return -ENODEV;
+ xxxfb_setup(option);
+#endif
+
+ return pci_register_driver(&xxxfb_driver);
+}
+
+static void __exit xxxfb_exit(void)
+{
+ pci_unregister_driver(&xxxfb_driver);
+}
+#else /* non PCI, platform drivers */
+#include <linux/platform_device.h>
+/* for platform devices */
+
+#ifdef CONFIG_PM
+/**
+ * xxxfb_suspend - Optional but recommended function. Suspend the device.
+ * @dev: platform device
+ * @msg: the suspend event code.
+ *
+ * See Documentation/driver-api/pm/devices.rst for more information
+ */
+static int xxxfb_suspend(struct platform_device *dev, pm_message_t msg)
+{
+ struct fb_info *info = platform_get_drvdata(dev);
+ struct xxxfb_par *par = info->par;
+
+ /* suspend here */
+ return 0;
+}
+
+/**
+ * xxxfb_resume - Optional but recommended function. Resume the device.
+ * @dev: platform device
+ *
+ * See Documentation/driver-api/pm/devices.rst for more information
+ */
+static int xxxfb_resume(struct platform_dev *dev)
+{
+ struct fb_info *info = platform_get_drvdata(dev);
+ struct xxxfb_par *par = info->par;
+
+ /* resume here */
+ return 0;
+}
+#else
+#define xxxfb_suspend NULL
+#define xxxfb_resume NULL
+#endif /* CONFIG_PM */
+
+static struct platform_device_driver xxxfb_driver = {
+ .probe = xxxfb_probe,
+ .remove = xxxfb_remove,
+ .suspend = xxxfb_suspend, /* optional but recommended */
+ .resume = xxxfb_resume, /* optional but recommended */
+ .driver = {
+ .name = "xxxfb",
+ },
+};
+
+static struct platform_device *xxxfb_device;
+
+#ifndef MODULE
+ /*
+ * Setup
+ */
+
+/*
+ * Only necessary if your driver takes special options,
+ * otherwise we fall back on the generic fb_setup().
+ */
+static int __init xxxfb_setup(char *options)
+{
+ /* Parse user specified options (`video=xxxfb:') */
+}
+#endif /* MODULE */
+
+static int __init xxxfb_init(void)
+{
+ int ret;
+ /*
+ * For kernel boot options (in 'video=xxxfb:<options>' format)
+ */
+#ifndef MODULE
+ char *option = NULL;
+
+ if (fb_get_options("xxxfb", &option))
+ return -ENODEV;
+ xxxfb_setup(option);
+#endif
+ ret = platform_driver_register(&xxxfb_driver);
+
+ if (!ret) {
+ xxxfb_device = platform_device_register_simple("xxxfb", 0,
+ NULL, 0);
+
+ if (IS_ERR(xxxfb_device)) {
+ platform_driver_unregister(&xxxfb_driver);
+ ret = PTR_ERR(xxxfb_device);
+ }
+ }
+
+ return ret;
+}
+
+static void __exit xxxfb_exit(void)
+{
+ platform_device_unregister(xxxfb_device);
+ platform_driver_unregister(&xxxfb_driver);
+}
+#endif /* CONFIG_PCI */
+
+/* ------------------------------------------------------------------------- */
+
+
+ /*
+ * Modularization
+ */
+
+module_init(xxxfb_init);
+module_exit(xxxfb_exit);
+
+MODULE_LICENSE("GPL");