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Release 4.11 drivers/video/fbdev/arcfb.c

/*
 * linux/drivers/video/arcfb.c -- FB driver for Arc monochrome LCD board
 *
 * Copyright (C) 2005, Jaya Kumar <jayalk@intworks.biz>
 *
 * 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.
 *
 * Layout is based on skeletonfb.c by James Simmons and Geert Uytterhoeven.
 *
 * This driver was written to be used with the Arc LCD board. Arc uses a
 * set of KS108 chips that control individual 64x64 LCD matrices. The board
 * can be paneled in a variety of setups such as 2x1=128x64, 4x4=256x256 and
 * so on. The interface between the board and the host is TTL based GPIO. The
 * GPIO requirements are 8 writable data lines and 4+n lines for control. On a
 * GPIO-less system, the board can be tested by connecting the respective sigs
 * up to a parallel port connector. The driver requires the IO addresses for
 * data and control GPIO at load time. It is unable to probe for the
 * existence of the LCD so it must be told at load time whether it should
 * be enabled or not.
 *
 * Todo:
 * - testing with 4x4
 * - testing with interrupt hw
 *
 * General notes:
 * - User must set tuhold. It's in microseconds. According to the 108 spec,
 *   the hold time is supposed to be at least 1 microsecond.
 * - User must set num_cols=x num_rows=y, eg: x=2 means 128
 * - User must set arcfb_enable=1 to enable it
 * - User must set dio_addr=0xIOADDR cio_addr=0xIOADDR
 *
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/arcfb.h>
#include <linux/platform_device.h>

#include <linux/uaccess.h>


#define floor8(a) (a&(~0x07))

#define floorXres(a,xres) (a&(~(xres - 1)))

#define iceil8(a) (((int)((a+7)/8))*8)

#define ceil64(a) (a|0x3F)

#define ceilXres(a,xres) (a|(xres - 1))

/* ks108 chipset specific defines and code */


#define KS_SET_DPY_START_LINE 	0xC0

#define KS_SET_PAGE_NUM 	0xB8

#define KS_SET_X 		0x40

#define KS_CEHI 		0x01

#define KS_CELO 		0x00

#define KS_SEL_CMD 		0x08

#define KS_SEL_DATA 		0x00

#define KS_DPY_ON 		0x3F

#define KS_DPY_OFF 		0x3E

#define KS_INTACK 		0x40

#define KS_CLRINT		0x02


struct arcfb_par {
	
unsigned long dio_addr;
	
unsigned long cio_addr;
	
unsigned long c2io_addr;
	
atomic_t ref_count;
	
unsigned char cslut[9];
	
struct fb_info *info;
	
unsigned int irq;
	
spinlock_t lock;
};


static const struct fb_fix_screeninfo arcfb_fix = {
	.id =		"arcfb",
	.type =		FB_TYPE_PACKED_PIXELS,
	.visual =	FB_VISUAL_MONO01,
	.xpanstep =	0,
	.ypanstep =	1,
	.ywrapstep =	0,
	.accel =	FB_ACCEL_NONE,
};


static const struct fb_var_screeninfo arcfb_var = {
	.xres		= 128,
	.yres		= 64,
	.xres_virtual	= 128,
	.yres_virtual	= 64,
	.bits_per_pixel	= 1,
	.nonstd		= 1,
};


static unsigned long num_cols;

static unsigned long num_rows;

static unsigned long dio_addr;

static unsigned long cio_addr;

static unsigned long c2io_addr;

static unsigned long splashval;

static unsigned long tuhold;

static unsigned int nosplash;

static unsigned int arcfb_enable;

static unsigned int irq;

static DECLARE_WAIT_QUEUE_HEAD(arcfb_waitq);


static void ks108_writeb_ctl(struct arcfb_par *par, unsigned int chipindex, unsigned char value) { unsigned char chipselval = par->cslut[chipindex]; outb(chipselval|KS_CEHI|KS_SEL_CMD, par->cio_addr); outb(value, par->dio_addr); udelay(tuhold); outb(chipselval|KS_CELO|KS_SEL_CMD, par->cio_addr); }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar70100.00%1100.00%
Total70100.00%1100.00%


static void ks108_writeb_mainctl(struct arcfb_par *par, unsigned char value) { outb(value, par->cio_addr); udelay(tuhold); }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar29100.00%1100.00%
Total29100.00%1100.00%


static unsigned char ks108_readb_ctl2(struct arcfb_par *par) { return inb(par->c2io_addr); }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar20100.00%1100.00%
Total20100.00%1100.00%


static void ks108_writeb_data(struct arcfb_par *par, unsigned int chipindex, unsigned char value) { unsigned char chipselval = par->cslut[chipindex]; outb(chipselval|KS_CEHI|KS_SEL_DATA, par->cio_addr); outb(value, par->dio_addr); udelay(tuhold); outb(chipselval|KS_CELO|KS_SEL_DATA, par->cio_addr); }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar70100.00%1100.00%
Total70100.00%1100.00%


static void ks108_set_start_line(struct arcfb_par *par, unsigned int chipindex, unsigned char y) { ks108_writeb_ctl(par, chipindex, KS_SET_DPY_START_LINE|y); }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar30100.00%1100.00%
Total30100.00%1100.00%


static void ks108_set_yaddr(struct arcfb_par *par, unsigned int chipindex, unsigned char y) { ks108_writeb_ctl(par, chipindex, KS_SET_PAGE_NUM|y); }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar30100.00%1100.00%
Total30100.00%1100.00%


static void ks108_set_xaddr(struct arcfb_par *par, unsigned int chipindex, unsigned char x) { ks108_writeb_ctl(par, chipindex, KS_SET_X|x); }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar30100.00%1100.00%
Total30100.00%1100.00%


static void ks108_clear_lcd(struct arcfb_par *par, unsigned int chipindex) { int i,j; for (i = 0; i <= 8; i++) { ks108_set_yaddr(par, chipindex, i); ks108_set_xaddr(par, chipindex, 0); for (j = 0; j < 64; j++) { ks108_writeb_data(par, chipindex, (unsigned char) splashval); } } }

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PersonTokensPropCommitsCommitProp
Jaya Kumar81100.00%1100.00%
Total81100.00%1100.00%

/* main arcfb functions */
static int arcfb_open(struct fb_info *info, int user) { struct arcfb_par *par = info->par; atomic_inc(&par->ref_count); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar34100.00%1100.00%
Total34100.00%1100.00%


static int arcfb_release(struct fb_info *info, int user) { struct arcfb_par *par = info->par; int count = atomic_read(&par->ref_count); if (!count) return -EINVAL; atomic_dec(&par->ref_count); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar54100.00%1100.00%
Total54100.00%1100.00%


static int arcfb_pan_display(struct fb_var_screeninfo *var, struct fb_info *info) { int i; struct arcfb_par *par = info->par; if ((var->vmode & FB_VMODE_YWRAP) && (var->yoffset < 64) && (info->var.yres <= 64)) { for (i = 0; i < num_cols; i++) { ks108_set_start_line(par, i, var->yoffset); } info->var.yoffset = var->yoffset; return 0; } return -EINVAL; }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar101100.00%1100.00%
Total101100.00%1100.00%


static irqreturn_t arcfb_interrupt(int vec, void *dev_instance) { struct fb_info *info = dev_instance; unsigned char ctl2status; struct arcfb_par *par = info->par; ctl2status = ks108_readb_ctl2(par); if (!(ctl2status & KS_INTACK)) /* not arc generated interrupt */ return IRQ_NONE; ks108_writeb_mainctl(par, KS_CLRINT); spin_lock(&par->lock); if (waitqueue_active(&arcfb_waitq)) { wake_up(&arcfb_waitq); } spin_unlock(&par->lock); return IRQ_HANDLED; }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar95100.00%1100.00%
Total95100.00%1100.00%

/* * here we handle a specific page on the lcd. the complexity comes from * the fact that the fb is laidout in 8xX vertical columns. we extract * each write of 8 vertical pixels. then we shift out as we move along * X. That's what rightshift does. bitmask selects the desired input bit. */
static void arcfb_lcd_update_page(struct arcfb_par *par, unsigned int upper, unsigned int left, unsigned int right, unsigned int distance) { unsigned char *src; unsigned int xindex, yindex, chipindex, linesize; int i; unsigned char val; unsigned char bitmask, rightshift; xindex = left >> 6; yindex = upper >> 6; chipindex = (xindex + (yindex*num_cols)); ks108_set_yaddr(par, chipindex, upper/8); linesize = par->info->var.xres/8; src = (unsigned char __force *) par->info->screen_base + (left/8) + (upper * linesize); ks108_set_xaddr(par, chipindex, left); bitmask=1; rightshift=0; while (left <= right) { val = 0; for (i = 0; i < 8; i++) { if ( i > rightshift) { val |= (*(src + (i*linesize)) & bitmask) << (i - rightshift); } else { val |= (*(src + (i*linesize)) & bitmask) >> (rightshift - i); } } ks108_writeb_data(par, chipindex, val); left++; if (bitmask == 0x80) { bitmask = 1; src++; rightshift=0; } else { bitmask <<= 1; rightshift++; } } }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar26497.78%150.00%
Antonino A. Daplas62.22%150.00%
Total270100.00%2100.00%

/* * here we handle the entire vertical page of the update. we write across * lcd chips. update_page uses the upper/left values to decide which * chip to select for the right. upper is needed for setting the page * desired for the write. */
static void arcfb_lcd_update_vert(struct arcfb_par *par, unsigned int top, unsigned int bottom, unsigned int left, unsigned int right) { unsigned int distance, upper, lower; distance = (bottom - top) + 1; upper = top; lower = top + 7; while (distance > 0) { distance -= 8; arcfb_lcd_update_page(par, upper, left, right, 8); upper = lower + 1; lower = upper + 7; } }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar92100.00%1100.00%
Total92100.00%1100.00%

/* * here we handle horizontal blocks for the update. update_vert will * handle spaning multiple pages. we break out each horizontal * block in to individual blocks no taller than 64 pixels. */
static void arcfb_lcd_update_horiz(struct arcfb_par *par, unsigned int left, unsigned int right, unsigned int top, unsigned int h) { unsigned int distance, upper, lower; distance = h; upper = floor8(top); lower = min(upper + distance - 1, ceil64(upper)); while (distance > 0) { distance -= ((lower - upper) + 1 ); arcfb_lcd_update_vert(par, upper, lower, left, right); upper = lower + 1; lower = min(upper + distance - 1, ceil64(upper)); } }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar117100.00%1100.00%
Total117100.00%1100.00%

/* * here we start the process of splitting out the fb update into * individual blocks of pixels. we end up splitting into 64x64 blocks * and finally down to 64x8 pages. */
static void arcfb_lcd_update(struct arcfb_par *par, unsigned int dx, unsigned int dy, unsigned int w, unsigned int h) { unsigned int left, right, distance, y; /* align the request first */ y = floor8(dy); h += dy - y; h = iceil8(h); distance = w; left = dx; right = min(left + w - 1, ceil64(left)); while (distance > 0) { arcfb_lcd_update_horiz(par, left, right, y, h); distance -= ((right - left) + 1); left = right + 1; right = min(left + distance - 1, ceil64(left)); } }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar137100.00%1100.00%
Total137100.00%1100.00%


static void arcfb_fillrect(struct fb_info *info, const struct fb_fillrect *rect) { struct arcfb_par *par = info->par; sys_fillrect(info, rect); /* update the physical lcd */ arcfb_lcd_update(par, rect->dx, rect->dy, rect->width, rect->height); }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar5396.36%133.33%
Adrian Bunk11.82%133.33%
Antonino A. Daplas11.82%133.33%
Total55100.00%3100.00%


static void arcfb_copyarea(struct fb_info *info, const struct fb_copyarea *area) { struct arcfb_par *par = info->par; sys_copyarea(info, area); /* update the physical lcd */ arcfb_lcd_update(par, area->dx, area->dy, area->width, area->height); }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar5396.36%133.33%
Antonino A. Daplas11.82%133.33%
Adrian Bunk11.82%133.33%
Total55100.00%3100.00%


static void arcfb_imageblit(struct fb_info *info, const struct fb_image *image) { struct arcfb_par *par = info->par; sys_imageblit(info, image); /* update the physical lcd */ arcfb_lcd_update(par, image->dx, image->dy, image->width, image->height); }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar5396.36%133.33%
Antonino A. Daplas11.82%133.33%
Adrian Bunk11.82%133.33%
Total55100.00%3100.00%


static int arcfb_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg) { void __user *argp = (void __user *)arg; struct arcfb_par *par = info->par; unsigned long flags; switch (cmd) { case FBIO_WAITEVENT: { DEFINE_WAIT(wait); /* illegal to wait on arc if no irq will occur */ if (!par->irq) return -EINVAL; /* wait until the Arc has generated an interrupt * which will wake us up */ spin_lock_irqsave(&par->lock, flags); prepare_to_wait(&arcfb_waitq, &wait, TASK_INTERRUPTIBLE); spin_unlock_irqrestore(&par->lock, flags); schedule(); finish_wait(&arcfb_waitq, &wait); } case FBIO_GETCONTROL2: { unsigned char ctl2; ctl2 = ks108_readb_ctl2(info->par); if (copy_to_user(argp, &ctl2, sizeof(ctl2))) return -EFAULT; return 0; } default: return -EINVAL; } }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar15998.76%150.00%
Christoph Hellwig21.24%150.00%
Total161100.00%2100.00%

/* * this is the access path from userspace. they can seek and write to * the fb. it's inefficient for them to do anything less than 64*8 * writes since we update the lcd in each write() anyway. */
static ssize_t arcfb_write(struct fb_info *info, const char __user *buf, size_t count, loff_t *ppos) { /* modded from epson 1355 */ unsigned long p; int err=-EINVAL; unsigned int fbmemlength,x,y,w,h, bitppos, startpos, endpos, bitcount; struct arcfb_par *par; unsigned int xres; p = *ppos; par = info->par; xres = info->var.xres; fbmemlength = (xres * info->var.yres)/8; if (p > fbmemlength) return -ENOSPC; err = 0; if ((count + p) > fbmemlength) { count = fbmemlength - p; err = -ENOSPC; } if (count) { char *base_addr; base_addr = (char __force *)info->screen_base; count -= copy_from_user(base_addr + p, buf, count); *ppos += count; err = -EFAULT; } bitppos = p*8; startpos = floorXres(bitppos, xres); endpos = ceilXres((bitppos + (count*8)), xres); bitcount = endpos - startpos; x = startpos % xres; y = startpos / xres; w = xres; h = bitcount / xres; arcfb_lcd_update(par, x, y, w, h); if (count) return count; return err; }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar24794.64%120.00%
Antonino A. Daplas134.98%360.00%
Al Viro10.38%120.00%
Total261100.00%5100.00%

static struct fb_ops arcfb_ops = { .owner = THIS_MODULE, .fb_open = arcfb_open, .fb_read = fb_sys_read, .fb_write = arcfb_write, .fb_release = arcfb_release, .fb_pan_display = arcfb_pan_display, .fb_fillrect = arcfb_fillrect, .fb_copyarea = arcfb_copyarea, .fb_imageblit = arcfb_imageblit, .fb_ioctl = arcfb_ioctl, };
static int arcfb_probe(struct platform_device *dev) { struct fb_info *info; int retval = -ENOMEM; int videomemorysize; unsigned char *videomemory; struct arcfb_par *par; int i; videomemorysize = (((64*64)*num_cols)*num_rows)/8; /* We need a flat backing store for the Arc's less-flat actual paged framebuffer */ videomemory = vzalloc(videomemorysize); if (!videomemory) return retval; info = framebuffer_alloc(sizeof(struct arcfb_par), &dev->dev); if (!info) goto err; info->screen_base = (char __iomem *)videomemory; info->fbops = &arcfb_ops; info->var = arcfb_var; info->fix = arcfb_fix; par = info->par; par->info = info; if (!dio_addr || !cio_addr || !c2io_addr) { printk(KERN_WARNING "no IO addresses supplied\n"); goto err1; } par->dio_addr = dio_addr; par->cio_addr = cio_addr; par->c2io_addr = c2io_addr; par->cslut[0] = 0x00; par->cslut[1] = 0x06; info->flags = FBINFO_FLAG_DEFAULT; spin_lock_init(&par->lock); retval = register_framebuffer(info); if (retval < 0) goto err1; platform_set_drvdata(dev, info); if (irq) { par->irq = irq; if (request_irq(par->irq, &arcfb_interrupt, IRQF_SHARED, "arcfb", info)) { printk(KERN_INFO "arcfb: Failed req IRQ %d\n", par->irq); retval = -EBUSY; goto err1; } } fb_info(info, "Arc frame buffer device, using %dK of video memory\n", videomemorysize >> 10); /* this inits the lcd but doesn't clear dirty pixels */ for (i = 0; i < num_cols * num_rows; i++) { ks108_writeb_ctl(par, i, KS_DPY_OFF); ks108_set_start_line(par, i, 0); ks108_set_yaddr(par, i, 0); ks108_set_xaddr(par, i, 0); ks108_writeb_ctl(par, i, KS_DPY_ON); } /* if we were told to splash the screen, we just clear it */ if (!nosplash) { for (i = 0; i < num_cols * num_rows; i++) { fb_info(info, "splashing lcd %d\n", i); ks108_set_start_line(par, i, 0); ks108_clear_lcd(par, i); } } return 0; err1: framebuffer_release(info); err: vfree(videomemory); return retval; }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar40695.08%116.67%
Joe Perches122.81%233.33%
Peter Senna Tschudin51.17%116.67%
Russell King30.70%116.67%
Thomas Gleixner10.23%116.67%
Total427100.00%6100.00%


static int arcfb_remove(struct platform_device *dev) { struct fb_info *info = platform_get_drvdata(dev); if (info) { unregister_framebuffer(info); vfree((void __force *)info->screen_base); framebuffer_release(info); } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar4382.69%133.33%
Antonino A. Daplas59.62%133.33%
Russell King47.69%133.33%
Total52100.00%3100.00%

static struct platform_driver arcfb_driver = { .probe = arcfb_probe, .remove = arcfb_remove, .driver = { .name = "arcfb", }, }; static struct platform_device *arcfb_device;
static int __init arcfb_init(void) { int ret; if (!arcfb_enable) return -ENXIO; ret = platform_driver_register(&arcfb_driver); if (!ret) { arcfb_device = platform_device_alloc("arcfb", 0); if (arcfb_device) { ret = platform_device_add(arcfb_device); } else { ret = -ENOMEM; } if (ret) { platform_device_put(arcfb_device); platform_driver_unregister(&arcfb_driver); } } return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar5361.63%133.33%
Russell King3338.37%266.67%
Total86100.00%3100.00%


static void __exit arcfb_exit(void) { platform_device_unregister(arcfb_device); platform_driver_unregister(&arcfb_driver); }

Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar1995.00%150.00%
Russell King15.00%150.00%
Total20100.00%2100.00%

module_param(num_cols, ulong, 0); MODULE_PARM_DESC(num_cols, "Num horiz panels, eg: 2 = 128 bit wide"); module_param(num_rows, ulong, 0); MODULE_PARM_DESC(num_rows, "Num vert panels, eg: 1 = 64 bit high"); module_param(nosplash, uint, 0); MODULE_PARM_DESC(nosplash, "Disable doing the splash screen"); module_param(arcfb_enable, uint, 0); MODULE_PARM_DESC(arcfb_enable, "Enable communication with Arc board"); module_param(dio_addr, ulong, 0); MODULE_PARM_DESC(dio_addr, "IO address for data, eg: 0x480"); module_param(cio_addr, ulong, 0); MODULE_PARM_DESC(cio_addr, "IO address for control, eg: 0x400"); module_param(c2io_addr, ulong, 0); MODULE_PARM_DESC(c2io_addr, "IO address for secondary control, eg: 0x408"); module_param(splashval, ulong, 0); MODULE_PARM_DESC(splashval, "Splash pattern: 0xFF is black, 0x00 is green"); module_param(tuhold, ulong, 0); MODULE_PARM_DESC(tuhold, "Time to hold between strobing data to Arc board"); module_param(irq, uint, 0); MODULE_PARM_DESC(irq, "IRQ for the Arc board"); module_init(arcfb_init); module_exit(arcfb_exit); MODULE_DESCRIPTION("fbdev driver for Arc monochrome LCD board"); MODULE_AUTHOR("Jaya Kumar"); MODULE_LICENSE("GPL");

Overall Contributors

PersonTokensPropCommitsCommitProp
Jaya Kumar289796.15%15.00%
Russell King551.83%315.00%
Antonino A. Daplas321.06%525.00%
Joe Perches120.40%210.00%
Peter Senna Tschudin50.17%15.00%
Adrian Bunk30.10%15.00%
Christoph Hellwig20.07%15.00%
Julia Lawall20.07%15.00%
Al Viro10.03%15.00%
Thomas Gleixner10.03%15.00%
Justin P. Mattock10.03%15.00%
Masanari Iida10.03%15.00%
Krzysztof Helt10.03%15.00%
Greg Kroah-Hartman0.00%00.00%
Total3013100.00%20100.00%
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