diff options
Diffstat (limited to 'drivers/video/fbdev/arcfb.c')
-rw-r--r-- | drivers/video/fbdev/arcfb.c | 674 |
1 files changed, 674 insertions, 0 deletions
diff --git a/drivers/video/fbdev/arcfb.c b/drivers/video/fbdev/arcfb.c new file mode 100644 index 000000000..08da43626 --- /dev/null +++ b/drivers/video/fbdev/arcfb.c @@ -0,0 +1,674 @@ +/* + * 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); +} + +static void ks108_writeb_mainctl(struct arcfb_par *par, unsigned char value) +{ + + outb(value, par->cio_addr); + udelay(tuhold); +} + +static unsigned char ks108_readb_ctl2(struct arcfb_par *par) +{ + return inb(par->c2io_addr); +} + +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); +} + +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); +} + +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); +} + +static void ks108_set_xaddr(struct arcfb_par *par, + unsigned int chipindex, unsigned char x) +{ + ks108_writeb_ctl(par, chipindex, KS_SET_X|x); +} + +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); + } + } +} + +/* 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; +} + +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; +} + +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; +} + +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; +} + +/* + * 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++; + } + } +} + +/* + * 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; + } +} + +/* + * 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)); + } +} + +/* + * 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)); + } +} + +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); +} + +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); +} + +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); +} + +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); + } + fallthrough; + + 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; + } +} + +/* + * 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; +} + +static const 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_fb_alloc; + + 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 err_addr; + } + 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); + 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 err_addr; + } + } + retval = register_framebuffer(info); + if (retval < 0) + goto err_register_fb; + platform_set_drvdata(dev, info); + 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; + +err_register_fb: + free_irq(par->irq, info); +err_addr: + framebuffer_release(info); +err_fb_alloc: + vfree(videomemory); + return retval; +} + +static int arcfb_remove(struct platform_device *dev) +{ + struct fb_info *info = platform_get_drvdata(dev); + + if (info) { + unregister_framebuffer(info); + if (irq) + free_irq(((struct arcfb_par *)(info->par))->irq, info); + vfree((void __force *)info->screen_base); + framebuffer_release(info); + } + return 0; +} + +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; + +} + +static void __exit arcfb_exit(void) +{ + platform_device_unregister(arcfb_device); + platform_driver_unregister(&arcfb_driver); +} + +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_hw(dio_addr, ulong, ioport, 0); +MODULE_PARM_DESC(dio_addr, "IO address for data, eg: 0x480"); +module_param_hw(cio_addr, ulong, ioport, 0); +MODULE_PARM_DESC(cio_addr, "IO address for control, eg: 0x400"); +module_param_hw(c2io_addr, ulong, ioport, 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_hw(irq, uint, irq, 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"); + |