Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965150AbXBQKml (ORCPT ); Sat, 17 Feb 2007 05:42:41 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932699AbXBQKml (ORCPT ); Sat, 17 Feb 2007 05:42:41 -0500 Received: from nz-out-0506.google.com ([64.233.162.226]:56851 "EHLO nz-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932698AbXBQKmj (ORCPT ); Sat, 17 Feb 2007 05:42:39 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:date:from:to:subject:message-id:mime-version:content-type:content-disposition:user-agent; b=UwDdWaJcV+pewC9gc8LpgQniOxdQ3llYbkA04h06d0FprkAKgyHuWQrexE3QZYu1A2UKfIrLJA+MXFY+NLUJg19YZ6l3g0iLKebCsTr08hT+IhaCxgPrsX9yE8z1aA9DKYqQj/CavBctBKEtn5MO32M41gA0WuK0a74y0IqjG+s= Date: Sat, 17 Feb 2007 11:42:15 +0100 From: Jaya Kumar To: linux-fbdev-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 2.6.20 1/1] fbdev,mm: hecuba/E-Ink fbdev driver Message-ID: <20070217104215.GB25512@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 17901 Lines: 667 Hi James, Geert, lkml and mm, This patch adds support for the Hecuba/E-Ink display with deferred IO. The changes from the previous version are to switch to using a mutex and lock_page. I welcome your feedback and advice. Signed-off-by: Jaya Kumar --- drivers/video/Kconfig | 13 + drivers/video/Makefile | 1 drivers/video/hecubafb.c | 590 +++++++++++++++++++++++++++++++++++++++++++++++ mm/rmap.c | 1 4 files changed, 605 insertions(+) --- diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig index 8874cf2..151b6e0 100644 --- a/drivers/video/Kconfig +++ b/drivers/video/Kconfig @@ -540,6 +540,19 @@ config FB_IMAC help This is the frame buffer device driver for the Intel-based Macintosh +config FB_HECUBA + tristate "Hecuba board support" + depends on FB && X86 && MMU + select FB_CFB_FILLRECT + select FB_CFB_COPYAREA + select FB_CFB_IMAGEBLIT + help + This enables support for the Hecuba board. This driver was tested + with an E-Ink 800x600 display and x86 SBCs through a 16 bit GPIO + interface (8 bit data, 4 bit control). If you anticpate using + this driver, say Y or M; otherwise say N. You must specify the + GPIO IO address to be used for setting control and data. + config FB_HGA tristate "Hercules mono graphics support" depends on FB && X86 diff --git a/drivers/video/Makefile b/drivers/video/Makefile index 6801edf..e9edf8e 100644 --- a/drivers/video/Makefile +++ b/drivers/video/Makefile @@ -65,6 +65,7 @@ obj-$(CONFIG_FB_SGIVW) += sgivwfb.o obj-$(CONFIG_FB_ACORN) += acornfb.o obj-$(CONFIG_FB_ATARI) += atafb.o obj-$(CONFIG_FB_MAC) += macfb.o +obj-$(CONFIG_FB_HECUBA) += hecubafb.o obj-$(CONFIG_FB_HGA) += hgafb.o obj-$(CONFIG_FB_IGA) += igafb.o obj-$(CONFIG_FB_APOLLO) += dnfb.o diff --git a/drivers/video/hecubafb.c b/drivers/video/hecubafb.c new file mode 100644 index 0000000..f0f538d --- /dev/null +++ b/drivers/video/hecubafb.c @@ -0,0 +1,590 @@ +/* + * linux/drivers/video/hecubafb.c -- FB driver for Hecuba controller + * + * Copyright (C) 2006, Jaya Kumar + * This work was sponsored by CIS(M) Sdn Bhd + * + * 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 work was possible because of apollo display code from E-Ink's website + * http://support.eink.com/community + * All information used to write this code is from public material made + * available by E-Ink on its support site. Some commands such as 0xA4 + * were found by looping through cmd=0x00 thru 0xFF and supplying random + * values. There are other commands that the display is capable of, + * beyond the 5 used here but they are more complex. + * + * This driver is written to be used with the Hecuba display controller + * board, and tested with the EInk 800x600 display in 1 bit mode. + * The interface between Hecuba and the host is TTL based GPIO. The + * GPIO requirements are 8 writable data lines and 6 lines for control. + * Only 4 of the controls are actually used here but 6 for future use. + * The driver requires the IO addresses for data and control GPIO at + * load time. It is also possible to use this display with a standard + * PC parallel port. + * + * General notes: + * - User must set hecubafb_enable=1 to enable it + * - User must set dio_addr=0xIOADDR cio_addr=0xIOADDR c2io_addr=0xIOADDR + * + * Explaination for deferred IO: + * - userspace app like Xfbdev mmaps framebuffer + * - driver handles and sets up nopage and page_mkwrite handlers + * - app tries to write to mmaped vaddress + * - get pagefault and reaches driver's nopage handler + * - driver's nopage handler finds and returns physical page ( no + * actual framebuffer ) + * - write so get page_mkwrite where we add this page to a list + * - also schedules a workqueue task to be run after a delay + * - app continues writing to that page with no additional cost + * - the workqueue task then does page_mkclean for the pages on + * the list, then completes the updating of the framebuffer + * - app tries to write to the address (that was just cleaned) + * - get pagefault and the above sequence occurs again + * + * The desire is roughly to allow bursty framebuffer writes to occur. + * Then after some time when hopefully things have gone quiet, we go and + * really update the framebuffer. For this type of nonvolatile high latency + * display, the desired image is the final image rather than intermediate + * stages which is why it's okay to not update for each write that is + * occuring. + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* to support deferred IO */ +#include +#include + +/* Apollo controller specific defines */ +#define APOLLO_START_NEW_IMG 0xA0 +#define APOLLO_STOP_IMG_DATA 0xA1 +#define APOLLO_DISPLAY_IMG 0xA2 +#define APOLLO_ERASE_DISPLAY 0xA3 +#define APOLLO_INIT_DISPLAY 0xA4 + +/* Hecuba interface specific defines */ +/* WUP is inverted, CD is inverted, DS is inverted */ +#define HCB_NWUP_BIT 0x01 +#define HCB_NDS_BIT 0x02 +#define HCB_RW_BIT 0x04 +#define HCB_NCD_BIT 0x08 +#define HCB_ACK_BIT 0x80 + +/* Display specific information */ +#define DPY_W 600 +#define DPY_H 800 + +struct hecubafb_par { + struct delayed_work deferred_work; + unsigned long dio_addr; + unsigned long cio_addr; + unsigned long c2io_addr; + unsigned char ctl; + atomic_t ref_count; + atomic_t vma_count; + struct fb_info *info; + unsigned int irq; + struct mutex lock; + struct list_head pagelist; +}; + +struct page_list { + struct list_head list; + struct page *page; +}; + +static struct fb_fix_screeninfo hecubafb_fix __initdata = { + .id = "hecubafb", + .type = FB_TYPE_PACKED_PIXELS, + .visual = FB_VISUAL_MONO01, + .xpanstep = 0, + .ypanstep = 0, + .ywrapstep = 0, + .accel = FB_ACCEL_NONE, +}; + +static struct fb_var_screeninfo hecubafb_var __initdata = { + .xres = DPY_W, + .yres = DPY_H, + .xres_virtual = DPY_W, + .yres_virtual = DPY_H, + .bits_per_pixel = 1, + .nonstd = 1, +}; + +static unsigned long dio_addr; +static unsigned long cio_addr; +static unsigned long c2io_addr; +static unsigned long splashval; +static unsigned int nosplash; +static unsigned int hecubafb_enable; +static unsigned int irq; + +static DECLARE_WAIT_QUEUE_HEAD(hecubafb_waitq); + +static void hcb_set_ctl(struct hecubafb_par *par) +{ + outb(par->ctl, par->cio_addr); +} + +static unsigned char hcb_get_ctl(struct hecubafb_par *par) +{ + return inb(par->c2io_addr); +} + +static void hcb_set_data(struct hecubafb_par *par, unsigned char value) +{ + outb(value, par->dio_addr); +} + +static int __devinit apollo_init_control(struct hecubafb_par *par) +{ + unsigned char ctl; + /* for init, we want the following setup to be set: + WUP = lo + ACK = hi + DS = hi + RW = hi + CD = lo + */ + + /* write WUP to lo, DS to hi, RW to hi, CD to lo */ + par->ctl = HCB_NWUP_BIT | HCB_RW_BIT | HCB_NCD_BIT ; + par->ctl &= ~HCB_NDS_BIT; + hcb_set_ctl(par); + + /* check ACK is not lo */ + ctl = hcb_get_ctl(par); + if ((ctl & HCB_ACK_BIT)) { + printk(KERN_ERR "Fail because ACK is already low\n"); + return -ENXIO; + } + + return 0; +} + +void hcb_wait_for_ack(struct hecubafb_par *par) +{ + + int timeout; + unsigned char ctl; + + timeout=500; + do { + ctl = hcb_get_ctl(par); + if ((ctl & HCB_ACK_BIT)) + return; + udelay(1); + } while (timeout--); + printk(KERN_ERR "timed out waiting for ack\n"); +} + +void hcb_wait_for_ack_clear(struct hecubafb_par *par) +{ + + int timeout; + unsigned char ctl; + + timeout=500; + do { + ctl = hcb_get_ctl(par); + if (!(ctl & HCB_ACK_BIT)) + return; + udelay(1); + } while (timeout--); + printk(KERN_ERR "timed out waiting for clear\n"); +} + +void apollo_send_data(struct hecubafb_par *par, unsigned char data) +{ + /* set data */ + hcb_set_data(par, data); + + /* set DS low */ + par->ctl |= HCB_NDS_BIT; + hcb_set_ctl(par); + + hcb_wait_for_ack(par); + + /* set DS hi */ + par->ctl &= ~(HCB_NDS_BIT); + hcb_set_ctl(par); + + hcb_wait_for_ack_clear(par); +} + +void apollo_send_command(struct hecubafb_par *par, unsigned char data) +{ + /* command so set CD to high */ + par->ctl &= ~(HCB_NCD_BIT); + hcb_set_ctl(par); + + /* actually strobe with command */ + apollo_send_data(par, data); + + /* clear CD back to low */ + par->ctl |= (HCB_NCD_BIT); + hcb_set_ctl(par); +} + +/* main hecubafb functions */ + +static void hecubafb_dpy_update(struct hecubafb_par *par) +{ + int i; + unsigned char *buf = par->info->screen_base; + + apollo_send_command(par, 0xA0); + + for (i=0; i < (DPY_W*DPY_H/8); i++) { + apollo_send_data(par, *(buf++)); + } + + apollo_send_command(par, 0xA1); + apollo_send_command(par, 0xA2); +} + +static void hecubafb_fillrect(struct fb_info *info, + const struct fb_fillrect *rect) +{ + struct hecubafb_par *par = info->par; + + cfb_fillrect(info, rect); + + hecubafb_dpy_update(par); +} + +static void hecubafb_copyarea(struct fb_info *info, + const struct fb_copyarea *area) +{ + struct hecubafb_par *par = info->par; + + cfb_copyarea(info, area); + + hecubafb_dpy_update(par); +} + +static void hecubafb_imageblit(struct fb_info *info, + const struct fb_image *image) +{ + struct hecubafb_par *par = info->par; + + cfb_imageblit(info, image); + + hecubafb_dpy_update(par); +} + +/* + * this is the slow path from userspace. they can seek and write to + * the fb. it's inefficient to do anything less than a full screen draw + */ +static ssize_t hecubafb_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct inode *inode; + int fbidx; + struct fb_info *info; + unsigned long p; + int err=-EINVAL; + struct hecubafb_par *par; + unsigned int xres; + unsigned int fbmemlength; + + p = *ppos; + inode = file->f_dentry->d_inode; + fbidx = iminor(inode); + info = registered_fb[fbidx]; + + if (!info || !info->screen_base) + return -ENODEV; + + 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 = info->screen_base; + count -= copy_from_user(base_addr + p, buf, count); + *ppos += count; + err = -EFAULT; + } + + hecubafb_dpy_update(par); + + if (count) + return count; + + return err; +} + +/* this is to find and return the vmalloc-ed fb pages */ +static struct page* hecubafb_vm_nopage(struct vm_area_struct *vma, + unsigned long vaddr, int *type) +{ + unsigned long offset; + struct page *page; + struct fb_info *info = vma->vm_private_data; + + offset = (vaddr - vma->vm_start) + (vma->vm_pgoff << PAGE_SHIFT); + if (offset >= (DPY_W*DPY_H)/8) + return NOPAGE_SIGBUS; + + page = vmalloc_to_page(info->screen_base + offset); + if (!page) + return NOPAGE_OOM; + + get_page(page); + if (type) + *type = VM_FAULT_MINOR; + return page; +} + +static void hecubafb_work(struct work_struct *work) +{ + struct hecubafb_par *par = container_of(work, struct hecubafb_par, + deferred_work.work); + struct list_head *node, *next; + struct page_list *cur; + + /* here we unmap the pages, then do all deferred IO */ + mutex_lock(&par->lock); + list_for_each_safe(node, next, &par->pagelist) { + cur = list_entry(node, struct page_list, list); + list_del(node); + lock_page(cur->page); + page_mkclean(cur->page); + unlock_page(cur->page); + kfree(cur); + } + mutex_unlock(&par->lock); + hecubafb_dpy_update(par); +} + +static int hecubafb_page_mkwrite(struct vm_area_struct *vma, + struct page *page) +{ + struct fb_info *info = vma->vm_private_data; + struct hecubafb_par *par = info->par; + struct page_list *new; + + /* this is a callback we get when userspace first tries to + write to the page. we schedule a workqueue. that workqueue + will eventually unmap the touched pages and execute the + deferred framebuffer IO. then if userspace touches a page + again, we repeat the same scheme */ + + new = kzalloc(sizeof(struct page_list), GFP_KERNEL); + if (!new) + return -ENOMEM; + new->page = page; + + /* protect against the workqueue changing the page list */ + mutex_lock(&par->lock); + list_add(&new->list, &par->pagelist); + mutex_unlock(&par->lock); + + /* come back in 1s to process the deferred IO */ + schedule_delayed_work(&par->deferred_work, HZ); + return 0; +} + +static struct vm_operations_struct hecubafb_vm_ops = { + .nopage = hecubafb_vm_nopage, + .page_mkwrite = hecubafb_page_mkwrite, +}; + +static int hecubafb_mmap(struct fb_info *info, struct vm_area_struct *vma) +{ + vma->vm_ops = &hecubafb_vm_ops; + vma->vm_flags |= ( VM_IO | VM_RESERVED | VM_DONTEXPAND ); + vma->vm_private_data = info; + return 0; +} + +static struct fb_ops hecubafb_ops = { + .owner = THIS_MODULE, + .fb_write = hecubafb_write, + .fb_fillrect = hecubafb_fillrect, + .fb_copyarea = hecubafb_copyarea, + .fb_imageblit = hecubafb_imageblit, + .fb_mmap = hecubafb_mmap, +}; + +static int __devinit hecubafb_probe(struct platform_device *dev) +{ + struct fb_info *info; + int retval = -ENOMEM; + int videomemorysize; + unsigned char *videomemory; + struct hecubafb_par *par; + + videomemorysize = (DPY_W*DPY_H)/8; + + if (!(videomemory = vmalloc(videomemorysize))) + return retval; + + memset(videomemory, 0, videomemorysize); + + info = framebuffer_alloc(sizeof(struct hecubafb_par), &dev->dev); + if (!info) + goto err; + + info->screen_base = (char __iomem *) videomemory; + info->fbops = &hecubafb_ops; + + info->var = hecubafb_var; + info->fix = hecubafb_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; + info->flags = FBINFO_FLAG_DEFAULT; + mutex_init(&par->lock); + INIT_DELAYED_WORK(&par->deferred_work, hecubafb_work); + INIT_LIST_HEAD(&par->pagelist); + retval = register_framebuffer(info); + if (retval < 0) + goto err1; + platform_set_drvdata(dev, info); + + printk(KERN_INFO + "fb%d: Hecuba frame buffer device, using %dK of video memory\n", + info->node, videomemorysize >> 10); + + /* this inits the dpy */ + apollo_init_control(par); + + apollo_send_command(par, APOLLO_INIT_DISPLAY); + apollo_send_data(par, 0x81); + + /* have to wait while display resets */ + udelay(1000); + + /* if we were told to splash the screen, we just clear it */ + if (!nosplash) { + apollo_send_command(par, APOLLO_ERASE_DISPLAY); + apollo_send_data(par, splashval); + } + + return 0; +err1: + framebuffer_release(info); +err: + vfree(videomemory); + return retval; +} + +static int __devexit hecubafb_remove(struct platform_device *dev) +{ + struct fb_info *info = platform_get_drvdata(dev); + struct hecubafb_par *par; + + if (info) { + par = info->par; + cancel_delayed_work(&par->deferred_work); + flush_scheduled_work(); + unregister_framebuffer(info); + vfree(info->screen_base); + framebuffer_release(info); + } + return 0; +} + +static struct platform_driver hecubafb_driver = { + .probe = hecubafb_probe, + .remove = hecubafb_remove, + .driver = { + .name = "hecubafb", + }, +}; + +static struct platform_device *hecubafb_device; + +static int __init hecubafb_init(void) +{ + int ret; + + if (!hecubafb_enable) { + printk(KERN_ERR "Use hecubafb_enable to enable the device\n"); + return -ENXIO; + } + + ret = platform_driver_register(&hecubafb_driver); + if (!ret) { + hecubafb_device = platform_device_alloc("hecubafb", 0); + if (hecubafb_device) + ret = platform_device_add(hecubafb_device); + else + ret = -ENOMEM; + + if (ret) { + platform_device_put(hecubafb_device); + platform_driver_unregister(&hecubafb_driver); + } + } + return ret; + +} + +static void __exit hecubafb_exit(void) +{ + platform_device_unregister(hecubafb_device); + platform_driver_unregister(&hecubafb_driver); +} + +module_param(nosplash, uint, 0); +MODULE_PARM_DESC(nosplash, "Disable doing the splash screen"); +module_param(hecubafb_enable, uint, 0); +MODULE_PARM_DESC(hecubafb_enable, "Enable communication with Hecuba 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: 0x00 is black, 0x01 is white"); +module_param(irq, uint, 0); +MODULE_PARM_DESC(irq, "IRQ for the Hecuba board"); + +module_init(hecubafb_init); +module_exit(hecubafb_exit); + +MODULE_DESCRIPTION("fbdev driver for Hecuba board"); +MODULE_AUTHOR("Jaya Kumar"); +MODULE_LICENSE("GPL"); diff --git a/mm/rmap.c b/mm/rmap.c index 669acb2..0fa0521 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -496,6 +496,7 @@ int page_mkclean(struct page *page) return ret; } +EXPORT_SYMBOL_GPL(page_mkclean); /** * page_set_anon_rmap - setup new anonymous rmap - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/