[deliverable/linux.git] / drivers / hid / hid-picolcd_fb.c

/***************************************************************************
 *   Copyright (C) 2010-2012 by Bruno Prémont <bonbons@linux-vserver.org>  *
 *                                                                         *
 *   Based on Logitech G13 driver (v0.4)                                   *
 *     Copyright (C) 2009 by Rick L. Vinyard, Jr. <rvinyard@cs.nmsu.edu>   *
 *                                                                         *
 *   This program is free software: you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation, version 2 of the License.               *
 *                                                                         *
 *   This driver is distributed in the hope that it will be useful, but    *
 *   WITHOUT ANY WARRANTY; without even the implied warranty of            *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      *
 *   General Public License for more details.                              *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this software. If not see <http://www.gnu.org/licenses/>.  *
 ***************************************************************************/

#include <linux/hid.h>
#include <linux/vmalloc.h>
#include "usbhid/usbhid.h"
#include <linux/usb.h>

#include <linux/fb.h>
#include <linux/module.h>

#include "hid-picolcd.h"

/* Framebuffer
 *
 * The PicoLCD use a Topway LCD module of 256x64 pixel
 * This display area is tiled over 4 controllers with 8 tiles
 * each. Each tile has 8x64 pixel, each data byte representing
 * a 1-bit wide vertical line of the tile.
 *
 * The display can be updated at a tile granularity.
 *
 *       Chip 1           Chip 2           Chip 3           Chip 4
 * +----------------+----------------+----------------+----------------+
 * |     Tile 1     |     Tile 1     |     Tile 1     |     Tile 1     |
 * +----------------+----------------+----------------+----------------+
 * |     Tile 2     |     Tile 2     |     Tile 2     |     Tile 2     |
 * +----------------+----------------+----------------+----------------+
 *                                  ...
 * +----------------+----------------+----------------+----------------+
 * |     Tile 8     |     Tile 8     |     Tile 8     |     Tile 8     |
 * +----------------+----------------+----------------+----------------+
 */
#define PICOLCDFB_NAME "picolcdfb"
#define PICOLCDFB_WIDTH (256)
#define PICOLCDFB_HEIGHT (64)
#define PICOLCDFB_SIZE (PICOLCDFB_WIDTH * PICOLCDFB_HEIGHT / 8)

#define PICOLCDFB_UPDATE_RATE_LIMIT   10
#define PICOLCDFB_UPDATE_RATE_DEFAULT  2

/* Framebuffer visual structures */
static const struct fb_fix_screeninfo picolcdfb_fix = {
	.id          = PICOLCDFB_NAME,
	.type        = FB_TYPE_PACKED_PIXELS,
	.visual      = FB_VISUAL_MONO01,
	.xpanstep    = 0,
	.ypanstep    = 0,
	.ywrapstep   = 0,
	.line_length = PICOLCDFB_WIDTH / 8,
	.accel       = FB_ACCEL_NONE,
};

static const struct fb_var_screeninfo picolcdfb_var = {
	.xres           = PICOLCDFB_WIDTH,
	.yres           = PICOLCDFB_HEIGHT,
	.xres_virtual   = PICOLCDFB_WIDTH,
	.yres_virtual   = PICOLCDFB_HEIGHT,
	.width          = 103,
	.height         = 26,
	.bits_per_pixel = 1,
	.grayscale      = 1,
	.red            = {
		.offset = 0,
		.length = 1,
		.msb_right = 0,
	},
	.green          = {
		.offset = 0,
		.length = 1,
		.msb_right = 0,
	},
	.blue           = {
		.offset = 0,
		.length = 1,
		.msb_right = 0,
	},
	.transp         = {
		.offset = 0,
		.length = 0,
		.msb_right = 0,
	},
};

/* Send a given tile to PicoLCD */
static int picolcd_fb_send_tile(struct hid_device *hdev, int chip, int tile)
{
	struct picolcd_data *data = hid_get_drvdata(hdev);
	struct hid_report *report1 = picolcd_out_report(REPORT_LCD_CMD_DATA, hdev);
	struct hid_report *report2 = picolcd_out_report(REPORT_LCD_DATA, hdev);
	unsigned long flags;
	u8 *tdata;
	int i;

	if (!report1 || report1->maxfield != 1 || !report2 || report2->maxfield != 1)
		return -ENODEV;

	spin_lock_irqsave(&data->lock, flags);
	hid_set_field(report1->field[0],  0, chip << 2);
	hid_set_field(report1->field[0],  1, 0x02);
	hid_set_field(report1->field[0],  2, 0x00);
	hid_set_field(report1->field[0],  3, 0x00);
	hid_set_field(report1->field[0],  4, 0xb8 | tile);
	hid_set_field(report1->field[0],  5, 0x00);
	hid_set_field(report1->field[0],  6, 0x00);
	hid_set_field(report1->field[0],  7, 0x40);
	hid_set_field(report1->field[0],  8, 0x00);
	hid_set_field(report1->field[0],  9, 0x00);
	hid_set_field(report1->field[0], 10,   32);

	hid_set_field(report2->field[0],  0, (chip << 2) | 0x01);
	hid_set_field(report2->field[0],  1, 0x00);
	hid_set_field(report2->field[0],  2, 0x00);
	hid_set_field(report2->field[0],  3,   32);

	tdata = data->fb_vbitmap + (tile * 4 + chip) * 64;
	for (i = 0; i < 64; i++)
		if (i < 32)
			hid_set_field(report1->field[0], 11 + i, tdata[i]);
		else
			hid_set_field(report2->field[0], 4 + i - 32, tdata[i]);

	usbhid_submit_report(data->hdev, report1, USB_DIR_OUT);
	usbhid_submit_report(data->hdev, report2, USB_DIR_OUT);
	spin_unlock_irqrestore(&data->lock, flags);
	return 0;
}

/* Translate a single tile*/
static int picolcd_fb_update_tile(u8 *vbitmap, const u8 *bitmap, int bpp,
		int chip, int tile)
{
	int i, b, changed = 0;
	u8 tdata[64];
	u8 *vdata = vbitmap + (tile * 4 + chip) * 64;

	if (bpp == 1) {
		for (b = 7; b >= 0; b--) {
			const u8 *bdata = bitmap + tile * 256 + chip * 8 + b * 32;
			for (i = 0; i < 64; i++) {
				tdata[i] <<= 1;
				tdata[i] |= (bdata[i/8] >> (i % 8)) & 0x01;
			}
		}
	} else if (bpp == 8) {
		for (b = 7; b >= 0; b--) {
			const u8 *bdata = bitmap + (tile * 256 + chip * 8 + b * 32) * 8;
			for (i = 0; i < 64; i++) {
				tdata[i] <<= 1;
				tdata[i] |= (bdata[i] & 0x80) ? 0x01 : 0x00;
			}
		}
	} else {
		/* Oops, we should never get here! */
		WARN_ON(1);
		return 0;
	}

	for (i = 0; i < 64; i++)
		if (tdata[i] != vdata[i]) {
			changed = 1;
			vdata[i] = tdata[i];
		}
	return changed;
}

void picolcd_fb_refresh(struct picolcd_data *data)
{
	if (data->fb_info)
		schedule_delayed_work(&data->fb_info->deferred_work, 0);
}

/* Reconfigure LCD display */
int picolcd_fb_reset(struct picolcd_data *data, int clear)
{
	struct hid_report *report = picolcd_out_report(REPORT_LCD_CMD, data->hdev);
	int i, j;
	unsigned long flags;
	static const u8 mapcmd[8] = { 0x00, 0x02, 0x00, 0x64, 0x3f, 0x00, 0x64, 0xc0 };

	if (!report || report->maxfield != 1)
		return -ENODEV;

	spin_lock_irqsave(&data->lock, flags);
	for (i = 0; i < 4; i++) {
		for (j = 0; j < report->field[0]->maxusage; j++)
			if (j == 0)
				hid_set_field(report->field[0], j, i << 2);
			else if (j < sizeof(mapcmd))
				hid_set_field(report->field[0], j, mapcmd[j]);
			else
				hid_set_field(report->field[0], j, 0);
		usbhid_submit_report(data->hdev, report, USB_DIR_OUT);
	}

	data->status |= PICOLCD_READY_FB;
	spin_unlock_irqrestore(&data->lock, flags);

	if (data->fb_bitmap) {
		if (clear) {
			memset(data->fb_vbitmap, 0, PICOLCDFB_SIZE);
			memset(data->fb_bitmap, 0, PICOLCDFB_SIZE*data->fb_bpp);
		}
		data->fb_force = 1;
	}

	/* schedule first output of framebuffer */
	picolcd_fb_refresh(data);

	return 0;
}

/* Update fb_vbitmap from the screen_base and send changed tiles to device */
static void picolcd_fb_update(struct fb_info *info)
{
	int chip, tile, n;
	unsigned long flags;
	struct picolcd_data *data;

	mutex_lock(&info->lock);
	data = info->par;
	if (!data)
		goto out;

	spin_lock_irqsave(&data->lock, flags);
	if (!(data->status & PICOLCD_READY_FB)) {
		spin_unlock_irqrestore(&data->lock, flags);
		picolcd_fb_reset(data, 0);
	} else {
		spin_unlock_irqrestore(&data->lock, flags);
	}

	/*
	 * Translate the framebuffer into the format needed by the PicoLCD.
	 * See display layout above.
	 * Do this one tile after the other and push those tiles that changed.
	 *
	 * Wait for our IO to complete as otherwise we might flood the queue!
	 */
	n = 0;
	for (chip = 0; chip < 4; chip++)
		for (tile = 0; tile < 8; tile++)
			if (picolcd_fb_update_tile(data->fb_vbitmap,
					data->fb_bitmap, data->fb_bpp, chip, tile) ||
				data->fb_force) {
				n += 2;
				if (n >= HID_OUTPUT_FIFO_SIZE / 2) {
					mutex_unlock(&info->lock);
					usbhid_wait_io(data->hdev);
					mutex_lock(&info->lock);
					data = info->par;
					if (!data)
						goto out;
					spin_lock_irqsave(&data->lock, flags);
					if (data->status & PICOLCD_FAILED) {
						spin_unlock_irqrestore(&data->lock, flags);
						goto out;
					}
					spin_unlock_irqrestore(&data->lock, flags);
					n = 0;
				}
				picolcd_fb_send_tile(data->hdev, chip, tile);
			}
	data->fb_force = false;
	if (n) {
		mutex_unlock(&info->lock);
		usbhid_wait_io(data->hdev);
		return;
	}
out:
	mutex_unlock(&info->lock);
}

/* Stub to call the system default and update the image on the picoLCD */
static void picolcd_fb_fillrect(struct fb_info *info,
		const struct fb_fillrect *rect)
{
	if (!info->par)
		return;
	sys_fillrect(info, rect);

	schedule_delayed_work(&info->deferred_work, 0);
}

/* Stub to call the system default and update the image on the picoLCD */
static void picolcd_fb_copyarea(struct fb_info *info,
		const struct fb_copyarea *area)
{
	if (!info->par)
		return;
	sys_copyarea(info, area);

	schedule_delayed_work(&info->deferred_work, 0);
}

/* Stub to call the system default and update the image on the picoLCD */
static void picolcd_fb_imageblit(struct fb_info *info, const struct fb_image *image)
{
	if (!info->par)
		return;
	sys_imageblit(info, image);

	schedule_delayed_work(&info->deferred_work, 0);
}

/*
 * 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 picolcd_fb_write(struct fb_info *info, const char __user *buf,
		size_t count, loff_t *ppos)
{
	ssize_t ret;
	if (!info->par)
		return -ENODEV;
	ret = fb_sys_write(info, buf, count, ppos);
	if (ret >= 0)
		schedule_delayed_work(&info->deferred_work, 0);
	return ret;
}

static int picolcd_fb_blank(int blank, struct fb_info *info)
{
	if (!info->par)
		return -ENODEV;
	/* We let fb notification do this for us via lcd/backlight device */
	return 0;
}

static void picolcd_fb_destroy(struct fb_info *info)
{
	/* make sure no work is deferred */
	fb_deferred_io_cleanup(info);

	vfree((u8 *)info->fix.smem_start);
	framebuffer_release(info);
	printk(KERN_DEBUG "picolcd_fb_destroy(%p)\n", info);
}

static int picolcd_fb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
{
	__u32 bpp      = var->bits_per_pixel;
	__u32 activate = var->activate;

	/* only allow 1/8 bit depth (8-bit is grayscale) */
	*var = picolcdfb_var;
	var->activate = activate;
	if (bpp >= 8) {
		var->bits_per_pixel = 8;
		var->red.length     = 8;
		var->green.length   = 8;
		var->blue.length    = 8;
	} else {
		var->bits_per_pixel = 1;
		var->red.length     = 1;
		var->green.length   = 1;
		var->blue.length    = 1;
	}
	return 0;
}

static int picolcd_set_par(struct fb_info *info)
{
	struct picolcd_data *data = info->par;
	u8 *tmp_fb, *o_fb;
	if (!data)
		return -ENODEV;
	if (info->var.bits_per_pixel == data->fb_bpp)
		return 0;
	/* switch between 1/8 bit depths */
	if (info->var.bits_per_pixel != 1 && info->var.bits_per_pixel != 8)
		return -EINVAL;

	o_fb   = data->fb_bitmap;
	tmp_fb = kmalloc(PICOLCDFB_SIZE*info->var.bits_per_pixel, GFP_KERNEL);
	if (!tmp_fb)
		return -ENOMEM;

	/* translate FB content to new bits-per-pixel */
	if (info->var.bits_per_pixel == 1) {
		int i, b;
		for (i = 0; i < PICOLCDFB_SIZE; i++) {
			u8 p = 0;
			for (b = 0; b < 8; b++) {
				p <<= 1;
				p |= o_fb[i*8+b] ? 0x01 : 0x00;
			}
			tmp_fb[i] = p;
		}
		memcpy(o_fb, tmp_fb, PICOLCDFB_SIZE);
		info->fix.visual = FB_VISUAL_MONO01;
		info->fix.line_length = PICOLCDFB_WIDTH / 8;
	} else {
		int i;
		memcpy(tmp_fb, o_fb, PICOLCDFB_SIZE);
		for (i = 0; i < PICOLCDFB_SIZE * 8; i++)
			o_fb[i] = tmp_fb[i/8] & (0x01 << (7 - i % 8)) ? 0xff : 0x00;
		info->fix.visual = FB_VISUAL_DIRECTCOLOR;
		info->fix.line_length = PICOLCDFB_WIDTH;
	}

	kfree(tmp_fb);
	data->fb_bpp      = info->var.bits_per_pixel;
	return 0;
}

/* Note this can't be const because of struct fb_info definition */
static struct fb_ops picolcdfb_ops = {
	.owner        = THIS_MODULE,
	.fb_destroy   = picolcd_fb_destroy,
	.fb_read      = fb_sys_read,
	.fb_write     = picolcd_fb_write,
	.fb_blank     = picolcd_fb_blank,
	.fb_fillrect  = picolcd_fb_fillrect,
	.fb_copyarea  = picolcd_fb_copyarea,
	.fb_imageblit = picolcd_fb_imageblit,
	.fb_check_var = picolcd_fb_check_var,
	.fb_set_par   = picolcd_set_par,
};


/* Callback from deferred IO workqueue */
static void picolcd_fb_deferred_io(struct fb_info *info, struct list_head *pagelist)
{
	picolcd_fb_update(info);
}

static const struct fb_deferred_io picolcd_fb_defio = {
	.delay = HZ / PICOLCDFB_UPDATE_RATE_DEFAULT,
	.deferred_io = picolcd_fb_deferred_io,
};


/*
 * The "fb_update_rate" sysfs attribute
 */
static ssize_t picolcd_fb_update_rate_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct picolcd_data *data = dev_get_drvdata(dev);
	unsigned i, fb_update_rate = data->fb_update_rate;
	size_t ret = 0;

	for (i = 1; i <= PICOLCDFB_UPDATE_RATE_LIMIT; i++)
		if (ret >= PAGE_SIZE)
			break;
		else if (i == fb_update_rate)
			ret += snprintf(buf+ret, PAGE_SIZE-ret, "[%u] ", i);
		else
			ret += snprintf(buf+ret, PAGE_SIZE-ret, "%u ", i);
	if (ret > 0)
		buf[min(ret, (size_t)PAGE_SIZE)-1] = '\n';
	return ret;
}

static ssize_t picolcd_fb_update_rate_store(struct device *dev,
		struct device_attribute *attr, const char *buf, size_t count)
{
	struct picolcd_data *data = dev_get_drvdata(dev);
	int i;
	unsigned u;

	if (count < 1 || count > 10)
		return -EINVAL;

	i = sscanf(buf, "%u", &u);
	if (i != 1)
		return -EINVAL;

	if (u > PICOLCDFB_UPDATE_RATE_LIMIT)
		return -ERANGE;
	else if (u == 0)
		u = PICOLCDFB_UPDATE_RATE_DEFAULT;

	data->fb_update_rate = u;
	data->fb_info->fbdefio->delay = HZ / data->fb_update_rate;
	return count;
}

static DEVICE_ATTR(fb_update_rate, 0666, picolcd_fb_update_rate_show,
		picolcd_fb_update_rate_store);

/* initialize Framebuffer device */
int picolcd_init_framebuffer(struct picolcd_data *data)
{
	struct device *dev = &data->hdev->dev;
	struct fb_info *info = NULL;
	int i, error = -ENOMEM;
	u8 *fb_vbitmap = NULL;
	u8 *fb_bitmap  = NULL;
	u32 *palette;

	fb_bitmap = vmalloc(PICOLCDFB_SIZE*8);
	if (fb_bitmap == NULL) {
		dev_err(dev, "can't get a free page for framebuffer\n");
		goto err_nomem;
	}

	fb_vbitmap = kmalloc(PICOLCDFB_SIZE, GFP_KERNEL);
	if (fb_vbitmap == NULL) {
		dev_err(dev, "can't alloc vbitmap image buffer\n");
		goto err_nomem;
	}

	data->fb_update_rate = PICOLCDFB_UPDATE_RATE_DEFAULT;
	/* The extra memory is:
	 * - 256*u32 for pseudo_palette
	 * - struct fb_deferred_io
	 */
	info = framebuffer_alloc(256 * sizeof(u32) +
			sizeof(struct fb_deferred_io), dev);
	if (info == NULL) {
		dev_err(dev, "failed to allocate a framebuffer\n");
		goto err_nomem;
	}

	info->fbdefio = info->par;
	*info->fbdefio = picolcd_fb_defio;
	palette  = info->par + sizeof(struct fb_deferred_io);
	for (i = 0; i < 256; i++)
		palette[i] = i > 0 && i < 16 ? 0xff : 0;
	info->pseudo_palette = palette;
	info->screen_base = (char __force __iomem *)fb_bitmap;
	info->fbops = &picolcdfb_ops;
	info->var = picolcdfb_var;
	info->fix = picolcdfb_fix;
	info->fix.smem_len   = PICOLCDFB_SIZE*8;
	info->fix.smem_start = (unsigned long)fb_bitmap;
	info->par = data;
	info->flags = FBINFO_FLAG_DEFAULT;

	data->fb_vbitmap = fb_vbitmap;
	data->fb_bitmap  = fb_bitmap;
	data->fb_bpp     = picolcdfb_var.bits_per_pixel;
	error = picolcd_fb_reset(data, 1);
	if (error) {
		dev_err(dev, "failed to configure display\n");
		goto err_cleanup;
	}
	error = device_create_file(dev, &dev_attr_fb_update_rate);
	if (error) {
		dev_err(dev, "failed to create sysfs attributes\n");
		goto err_cleanup;
	}
	fb_deferred_io_init(info);
	data->fb_info    = info;
	error = register_framebuffer(info);
	if (error) {
		dev_err(dev, "failed to register framebuffer\n");
		goto err_sysfs;
	}
	/* schedule first output of framebuffer */
	data->fb_force = 1;
	schedule_delayed_work(&info->deferred_work, 0);
	return 0;

err_sysfs:
	fb_deferred_io_cleanup(info);
	device_remove_file(dev, &dev_attr_fb_update_rate);
err_cleanup:
	data->fb_vbitmap = NULL;
	data->fb_bitmap  = NULL;
	data->fb_bpp     = 0;
	data->fb_info    = NULL;

err_nomem:
	framebuffer_release(info);
	vfree(fb_bitmap);
	kfree(fb_vbitmap);
	return error;
}

void picolcd_exit_framebuffer(struct picolcd_data *data)
{
	struct fb_info *info = data->fb_info;
	u8 *fb_vbitmap = data->fb_vbitmap;

	if (!info)
		return;

	device_remove_file(&data->hdev->dev, &dev_attr_fb_update_rate);
	info->par = NULL;
	unregister_framebuffer(info);
	data->fb_vbitmap = NULL;
	data->fb_bitmap  = NULL;
	data->fb_bpp     = 0;
	data->fb_info    = NULL;
	kfree(fb_vbitmap);
}
Commit	Line	Data
fabdbf2f BP	1	/***************************************************************************
	2	* Copyright (C) 2010-2012 by Bruno Prémont <bonbons@linux-vserver.org> *
	3	* *
	4	* Based on Logitech G13 driver (v0.4) *
	5	* Copyright (C) 2009 by Rick L. Vinyard, Jr. <rvinyard@cs.nmsu.edu> *
	6	* *
	7	* This program is free software: you can redistribute it and/or modify *
	8	* it under the terms of the GNU General Public License as published by *
	9	* the Free Software Foundation, version 2 of the License. *
	10	* *
	11	* This driver is distributed in the hope that it will be useful, but *
	12	* WITHOUT ANY WARRANTY; without even the implied warranty of *
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU *
	14	* General Public License for more details. *
	15	* *
	16	* You should have received a copy of the GNU General Public License *
	17	* along with this software. If not see <http://www.gnu.org/licenses/>. *
	18	***************************************************************************/
	19
	20	#include <linux/hid.h>
d1c60a03	21	#include <linux/vmalloc.h>
fabdbf2f BP	22	#include "usbhid/usbhid.h"
	23	#include <linux/usb.h>
	24
	25	#include <linux/fb.h>
	26	#include <linux/module.h>
	27
	28	#include "hid-picolcd.h"
	29
	30	/* Framebuffer
	31	*
	32	* The PicoLCD use a Topway LCD module of 256x64 pixel
	33	* This display area is tiled over 4 controllers with 8 tiles
	34	* each. Each tile has 8x64 pixel, each data byte representing
	35	* a 1-bit wide vertical line of the tile.
	36	*
	37	* The display can be updated at a tile granularity.
	38	*
	39	* Chip 1 Chip 2 Chip 3 Chip 4
	40	* +----------------+----------------+----------------+----------------+
	41	* \| Tile 1 \| Tile 1 \| Tile 1 \| Tile 1 \|
	42	* +----------------+----------------+----------------+----------------+
	43	* \| Tile 2 \| Tile 2 \| Tile 2 \| Tile 2 \|
	44	* +----------------+----------------+----------------+----------------+
	45	* ...
	46	* +----------------+----------------+----------------+----------------+
	47	* \| Tile 8 \| Tile 8 \| Tile 8 \| Tile 8 \|
	48	* +----------------+----------------+----------------+----------------+
	49	*/
	50	#define PICOLCDFB_NAME "picolcdfb"
	51	#define PICOLCDFB_WIDTH (256)
	52	#define PICOLCDFB_HEIGHT (64)
	53	#define PICOLCDFB_SIZE (PICOLCDFB_WIDTH * PICOLCDFB_HEIGHT / 8)
	54
	55	#define PICOLCDFB_UPDATE_RATE_LIMIT 10
	56	#define PICOLCDFB_UPDATE_RATE_DEFAULT 2
	57
	58	/* Framebuffer visual structures */
	59	static const struct fb_fix_screeninfo picolcdfb_fix = {
	60	.id = PICOLCDFB_NAME,
	61	.type = FB_TYPE_PACKED_PIXELS,
	62	.visual = FB_VISUAL_MONO01,
	63	.xpanstep = 0,
	64	.ypanstep = 0,
	65	.ywrapstep = 0,
	66	.line_length = PICOLCDFB_WIDTH / 8,
	67	.accel = FB_ACCEL_NONE,
	68	};
	69
	70	static const struct fb_var_screeninfo picolcdfb_var = {
	71	.xres = PICOLCDFB_WIDTH,
	72	.yres = PICOLCDFB_HEIGHT,
	73	.xres_virtual = PICOLCDFB_WIDTH,
	74	.yres_virtual = PICOLCDFB_HEIGHT,
	75	.width = 103,
	76	.height = 26,
	77	.bits_per_pixel = 1,
	78	.grayscale = 1,
	79	.red = {
	80	.offset = 0,
	81	.length = 1,
	82	.msb_right = 0,
	83	},
	84	.green = {
	85	.offset = 0,
86	.length = 1,
87	.msb_right = 0,
88	},
89	.blue = {
90	.offset = 0,
91	.length = 1,
92	.msb_right = 0,
93	},
94	.transp = {
95	.offset = 0,
96	.length = 0,
97	.msb_right = 0,
98	},
99	};
100
101	/* Send a given tile to PicoLCD */
102	static int picolcd_fb_send_tile(struct hid_device *hdev, int chip, int tile)
103	{
104	struct picolcd_data *data = hid_get_drvdata(hdev);
105	struct hid_report *report1 = picolcd_out_report(REPORT_LCD_CMD_DATA, hdev);
106	struct hid_report *report2 = picolcd_out_report(REPORT_LCD_DATA, hdev);
107	unsigned long flags;
108	u8 *tdata;
109	int i;
110
111	if (!report1 \|\| report1->maxfield != 1 \|\| !report2 \|\| report2->maxfield != 1)
112	return -ENODEV;
113
114	spin_lock_irqsave(&data->lock, flags);
115	hid_set_field(report1->field[0], 0, chip << 2);
116	hid_set_field(report1->field[0], 1, 0x02);
117	hid_set_field(report1->field[0], 2, 0x00);
118	hid_set_field(report1->field[0], 3, 0x00);
119	hid_set_field(report1->field[0], 4, 0xb8 \| tile);
120	hid_set_field(report1->field[0], 5, 0x00);
121	hid_set_field(report1->field[0], 6, 0x00);
122	hid_set_field(report1->field[0], 7, 0x40);
123	hid_set_field(report1->field[0], 8, 0x00);
124	hid_set_field(report1->field[0], 9, 0x00);
125	hid_set_field(report1->field[0], 10, 32);
126
127	hid_set_field(report2->field[0], 0, (chip << 2) \| 0x01);
128	hid_set_field(report2->field[0], 1, 0x00);
129	hid_set_field(report2->field[0], 2, 0x00);
130	hid_set_field(report2->field[0], 3, 32);
131
132	tdata = data->fb_vbitmap + (tile * 4 + chip) * 64;
133	for (i = 0; i < 64; i++)
134	if (i < 32)
135	hid_set_field(report1->field[0], 11 + i, tdata[i]);
136	else
137	hid_set_field(report2->field[0], 4 + i - 32, tdata[i]);
138
139	usbhid_submit_report(data->hdev, report1, USB_DIR_OUT);
140	usbhid_submit_report(data->hdev, report2, USB_DIR_OUT);
141	spin_unlock_irqrestore(&data->lock, flags);
142	return 0;
143	}
144
145	/* Translate a single tile*/
146	static int picolcd_fb_update_tile(u8 vbitmap, const u8 bitmap, int bpp,
147	int chip, int tile)
148	{
149	int i, b, changed = 0;
150	u8 tdata[64];
151	u8 vdata = vbitmap + (tile 4 + chip) * 64;
152
153	if (bpp == 1) {
154	for (b = 7; b >= 0; b--) {
155	const u8 bdata = bitmap + tile 256 + chip * 8 + b * 32;
156	for (i = 0; i < 64; i++) {
157	tdata[i] <<= 1;
158	tdata[i] \|= (bdata[i/8] >> (i % 8)) & 0x01;
159	}
160	}
161	} else if (bpp == 8) {
162	for (b = 7; b >= 0; b--) {
163	const u8 bdata = bitmap + (tile 256 + chip * 8 + b * 32) * 8;
164	for (i = 0; i < 64; i++) {
165	tdata[i] <<= 1;
166	tdata[i] \|= (bdata[i] & 0x80) ? 0x01 : 0x00;
167	}
168	}
169	} else {
170	/* Oops, we should never get here! */
171	WARN_ON(1);
172	return 0;
173	}
174
175	for (i = 0; i < 64; i++)
176	if (tdata[i] != vdata[i]) {
177	changed = 1;
178	vdata[i] = tdata[i];
179	}
180	return changed;
181	}
182
183	void picolcd_fb_refresh(struct picolcd_data *data)
184	{
185	if (data->fb_info)
186	schedule_delayed_work(&data->fb_info->deferred_work, 0);
187	}
188
189	/* Reconfigure LCD display */
190	int picolcd_fb_reset(struct picolcd_data *data, int clear)
191	{
192	struct hid_report *report = picolcd_out_report(REPORT_LCD_CMD, data->hdev);
193	int i, j;
194	unsigned long flags;
195	static const u8 mapcmd[8] = { 0x00, 0x02, 0x00, 0x64, 0x3f, 0x00, 0x64, 0xc0 };
196
197	if (!report \|\| report->maxfield != 1)
198	return -ENODEV;
199
200	spin_lock_irqsave(&data->lock, flags);
201	for (i = 0; i < 4; i++) {
202	for (j = 0; j < report->field[0]->maxusage; j++)
203	if (j == 0)
204	hid_set_field(report->field[0], j, i << 2);
205	else if (j < sizeof(mapcmd))
206	hid_set_field(report->field[0], j, mapcmd[j]);
207	else
208	hid_set_field(report->field[0], j, 0);
209	usbhid_submit_report(data->hdev, report, USB_DIR_OUT);
210	}
211
212	data->status \|= PICOLCD_READY_FB;
213	spin_unlock_irqrestore(&data->lock, flags);
214
215	if (data->fb_bitmap) {
216	if (clear) {
217	memset(data->fb_vbitmap, 0, PICOLCDFB_SIZE);
218	memset(data->fb_bitmap, 0, PICOLCDFB_SIZE*data->fb_bpp);
219	}
220	data->fb_force = 1;
221	}
222
223	/* schedule first output of framebuffer */
224	picolcd_fb_refresh(data);
225
226	return 0;
227	}
228
229	/* Update fb_vbitmap from the screen_base and send changed tiles to device */
a93ab849	230	static void picolcd_fb_update(struct fb_info *info)
fabdbf2f BP	231	{
	232	int chip, tile, n;
	233	unsigned long flags;
a93ab849	234	struct picolcd_data *data;
fabdbf2f	235
a93ab849 BP	236	mutex_lock(&info->lock);
a93ab849 BP	237	data = info->par;
fabdbf2f	238	if (!data)
a93ab849	239	goto out;
fabdbf2f BP	240
	241	spin_lock_irqsave(&data->lock, flags);
	242	if (!(data->status & PICOLCD_READY_FB)) {
	243	spin_unlock_irqrestore(&data->lock, flags);
	244	picolcd_fb_reset(data, 0);
	245	} else {
	246	spin_unlock_irqrestore(&data->lock, flags);
	247	}
	248
	249	/*
	250	* Translate the framebuffer into the format needed by the PicoLCD.
	251	* See display layout above.
	252	* Do this one tile after the other and push those tiles that changed.
	253	*
	254	* Wait for our IO to complete as otherwise we might flood the queue!
	255	*/
	256	n = 0;
	257	for (chip = 0; chip < 4; chip++)
	258	for (tile = 0; tile < 8; tile++)
	259	if (picolcd_fb_update_tile(data->fb_vbitmap,
	260	data->fb_bitmap, data->fb_bpp, chip, tile) \|\|
	261	data->fb_force) {
	262	n += 2;
fabdbf2f	263	if (n >= HID_OUTPUT_FIFO_SIZE / 2) {
a93ab849	264	mutex_unlock(&info->lock);
fabdbf2f	265	usbhid_wait_io(data->hdev);
a93ab849 BP	266	mutex_lock(&info->lock);
	267	data = info->par;
	268	if (!data)
	269	goto out;
	270	spin_lock_irqsave(&data->lock, flags);
	271	if (data->status & PICOLCD_FAILED) {
	272	spin_unlock_irqrestore(&data->lock, flags);
	273	goto out;
	274	}
	275	spin_unlock_irqrestore(&data->lock, flags);
fabdbf2f BP	276	n = 0;
	277	}
	278	picolcd_fb_send_tile(data->hdev, chip, tile);
	279	}
	280	data->fb_force = false;
a93ab849 BP	281	if (n) {
a93ab849 BP	282	mutex_unlock(&info->lock);
fabdbf2f	283	usbhid_wait_io(data->hdev);
a93ab849 BP	284	return;
	285	}
	286	out:
	287	mutex_unlock(&info->lock);
fabdbf2f BP	288	}
	289
	290	/* Stub to call the system default and update the image on the picoLCD */
	291	static void picolcd_fb_fillrect(struct fb_info *info,
	292	const struct fb_fillrect *rect)
	293	{
	294	if (!info->par)
	295	return;
	296	sys_fillrect(info, rect);
	297
	298	schedule_delayed_work(&info->deferred_work, 0);
	299	}
	300
	301	/* Stub to call the system default and update the image on the picoLCD */
	302	static void picolcd_fb_copyarea(struct fb_info *info,
	303	const struct fb_copyarea *area)
	304	{
	305	if (!info->par)
	306	return;
	307	sys_copyarea(info, area);
	308
	309	schedule_delayed_work(&info->deferred_work, 0);
	310	}
	311
	312	/* Stub to call the system default and update the image on the picoLCD */
	313	static void picolcd_fb_imageblit(struct fb_info info, const struct fb_image image)
	314	{
	315	if (!info->par)
	316	return;
	317	sys_imageblit(info, image);
	318
	319	schedule_delayed_work(&info->deferred_work, 0);
	320	}
	321
	322	/*
	323	* this is the slow path from userspace. they can seek and write to
	324	* the fb. it's inefficient to do anything less than a full screen draw
	325	*/
	326	static ssize_t picolcd_fb_write(struct fb_info info, const char __user buf,
	327	size_t count, loff_t *ppos)
	328	{
	329	ssize_t ret;
	330	if (!info->par)
	331	return -ENODEV;
	332	ret = fb_sys_write(info, buf, count, ppos);
	333	if (ret >= 0)
	334	schedule_delayed_work(&info->deferred_work, 0);
	335	return ret;
	336	}
	337
	338	static int picolcd_fb_blank(int blank, struct fb_info *info)
	339	{
	340	if (!info->par)
	341	return -ENODEV;
	342	/* We let fb notification do this for us via lcd/backlight device */
	343	return 0;
	344	}
	345
	346	static void picolcd_fb_destroy(struct fb_info *info)
	347	{
9966c37c	348	/* make sure no work is deferred */
a93ab849	349	fb_deferred_io_cleanup(info);
fabdbf2f	350
9966c37c BP	351	vfree((u8 *)info->fix.smem_start);
9966c37c BP	352	framebuffer_release(info);
a93ab849	353	printk(KERN_DEBUG "picolcd_fb_destroy(%p)\n", info);
fabdbf2f BP	354	}
	355
	356	static int picolcd_fb_check_var(struct fb_var_screeninfo var, struct fb_info info)
	357	{
	358	__u32 bpp = var->bits_per_pixel;
	359	__u32 activate = var->activate;
	360
	361	/* only allow 1/8 bit depth (8-bit is grayscale) */
	362	*var = picolcdfb_var;
	363	var->activate = activate;
	364	if (bpp >= 8) {
	365	var->bits_per_pixel = 8;
	366	var->red.length = 8;
	367	var->green.length = 8;
	368	var->blue.length = 8;
	369	} else {
	370	var->bits_per_pixel = 1;
	371	var->red.length = 1;
	372	var->green.length = 1;
	373	var->blue.length = 1;
	374	}
	375	return 0;
	376	}
	377
	378	static int picolcd_set_par(struct fb_info *info)
	379	{
	380	struct picolcd_data *data = info->par;
	381	u8 tmp_fb, o_fb;
	382	if (!data)
	383	return -ENODEV;
	384	if (info->var.bits_per_pixel == data->fb_bpp)
	385	return 0;
	386	/* switch between 1/8 bit depths */
	387	if (info->var.bits_per_pixel != 1 && info->var.bits_per_pixel != 8)
	388	return -EINVAL;
	389
	390	o_fb = data->fb_bitmap;
	391	tmp_fb = kmalloc(PICOLCDFB_SIZE*info->var.bits_per_pixel, GFP_KERNEL);
	392	if (!tmp_fb)
	393	return -ENOMEM;
	394
	395	/* translate FB content to new bits-per-pixel */
	396	if (info->var.bits_per_pixel == 1) {
	397	int i, b;
	398	for (i = 0; i < PICOLCDFB_SIZE; i++) {
	399	u8 p = 0;
	400	for (b = 0; b < 8; b++) {
	401	p <<= 1;
	402	p \|= o_fb[i*8+b] ? 0x01 : 0x00;
	403	}
	404	tmp_fb[i] = p;
	405	}
	406	memcpy(o_fb, tmp_fb, PICOLCDFB_SIZE);
	407	info->fix.visual = FB_VISUAL_MONO01;
	408	info->fix.line_length = PICOLCDFB_WIDTH / 8;
	409	} else {
	410	int i;
	411	memcpy(tmp_fb, o_fb, PICOLCDFB_SIZE);
	412	for (i = 0; i < PICOLCDFB_SIZE * 8; i++)
	413	o_fb[i] = tmp_fb[i/8] & (0x01 << (7 - i % 8)) ? 0xff : 0x00;
	414	info->fix.visual = FB_VISUAL_DIRECTCOLOR;
	415	info->fix.line_length = PICOLCDFB_WIDTH;
	416	}
	417
418	kfree(tmp_fb);
419	data->fb_bpp = info->var.bits_per_pixel;
420	return 0;
421	}
422
fabdbf2f BP	423	/* Note this can't be const because of struct fb_info definition */
	424	static struct fb_ops picolcdfb_ops = {
	425	.owner = THIS_MODULE,
	426	.fb_destroy = picolcd_fb_destroy,
fabdbf2f BP	427	.fb_read = fb_sys_read,
	428	.fb_write = picolcd_fb_write,
	429	.fb_blank = picolcd_fb_blank,
	430	.fb_fillrect = picolcd_fb_fillrect,
	431	.fb_copyarea = picolcd_fb_copyarea,
	432	.fb_imageblit = picolcd_fb_imageblit,
	433	.fb_check_var = picolcd_fb_check_var,
	434	.fb_set_par = picolcd_set_par,
	435	};
	436
	437
	438	/* Callback from deferred IO workqueue */
	439	static void picolcd_fb_deferred_io(struct fb_info info, struct list_head pagelist)
	440	{
a93ab849	441	picolcd_fb_update(info);
fabdbf2f BP	442	}
	443
	444	static const struct fb_deferred_io picolcd_fb_defio = {
	445	.delay = HZ / PICOLCDFB_UPDATE_RATE_DEFAULT,
	446	.deferred_io = picolcd_fb_deferred_io,
	447	};
	448
	449
	450	/*
	451	* The "fb_update_rate" sysfs attribute
	452	*/
	453	static ssize_t picolcd_fb_update_rate_show(struct device *dev,
	454	struct device_attribute attr, char buf)
	455	{
	456	struct picolcd_data *data = dev_get_drvdata(dev);
	457	unsigned i, fb_update_rate = data->fb_update_rate;
	458	size_t ret = 0;
	459
	460	for (i = 1; i <= PICOLCDFB_UPDATE_RATE_LIMIT; i++)
	461	if (ret >= PAGE_SIZE)
	462	break;
	463	else if (i == fb_update_rate)
	464	ret += snprintf(buf+ret, PAGE_SIZE-ret, "[%u] ", i);
	465	else
	466	ret += snprintf(buf+ret, PAGE_SIZE-ret, "%u ", i);
	467	if (ret > 0)
	468	buf[min(ret, (size_t)PAGE_SIZE)-1] = '\n';
	469	return ret;
	470	}
	471
	472	static ssize_t picolcd_fb_update_rate_store(struct device *dev,
	473	struct device_attribute attr, const char buf, size_t count)
	474	{
	475	struct picolcd_data *data = dev_get_drvdata(dev);
	476	int i;
	477	unsigned u;
	478
	479	if (count < 1 \|\| count > 10)
	480	return -EINVAL;
	481
	482	i = sscanf(buf, "%u", &u);
	483	if (i != 1)
	484	return -EINVAL;
	485
	486	if (u > PICOLCDFB_UPDATE_RATE_LIMIT)
	487	return -ERANGE;
	488	else if (u == 0)
	489	u = PICOLCDFB_UPDATE_RATE_DEFAULT;
	490
	491	data->fb_update_rate = u;
9966c37c	492	data->fb_info->fbdefio->delay = HZ / data->fb_update_rate;
fabdbf2f BP	493	return count;
	494	}
	495
	496	static DEVICE_ATTR(fb_update_rate, 0666, picolcd_fb_update_rate_show,
	497	picolcd_fb_update_rate_store);
	498
	499	/* initialize Framebuffer device */
	500	int picolcd_init_framebuffer(struct picolcd_data *data)
	501	{
	502	struct device *dev = &data->hdev->dev;
	503	struct fb_info *info = NULL;
	504	int i, error = -ENOMEM;
	505	u8 *fb_vbitmap = NULL;
	506	u8 *fb_bitmap = NULL;
	507	u32 *palette;
	508
	509	fb_bitmap = vmalloc(PICOLCDFB_SIZE*8);
	510	if (fb_bitmap == NULL) {
	511	dev_err(dev, "can't get a free page for framebuffer\n");
	512	goto err_nomem;
	513	}
	514
	515	fb_vbitmap = kmalloc(PICOLCDFB_SIZE, GFP_KERNEL);
	516	if (fb_vbitmap == NULL) {
	517	dev_err(dev, "can't alloc vbitmap image buffer\n");
	518	goto err_nomem;
	519	}
	520
	521	data->fb_update_rate = PICOLCDFB_UPDATE_RATE_DEFAULT;
fabdbf2f	522	/* The extra memory is:
fabdbf2f	523	* - 256*u32 for pseudo_palette
9966c37c	524	* - struct fb_deferred_io
fabdbf2f	525	*/
9966c37c BP	526	info = framebuffer_alloc(256 * sizeof(u32) +
9966c37c BP	527	sizeof(struct fb_deferred_io), dev);
fabdbf2f BP	528	if (info == NULL) {
	529	dev_err(dev, "failed to allocate a framebuffer\n");
	530	goto err_nomem;
	531	}
	532
9966c37c BP	533	info->fbdefio = info->par;
	534	*info->fbdefio = picolcd_fb_defio;
	535	palette = info->par + sizeof(struct fb_deferred_io);
fabdbf2f BP	536	for (i = 0; i < 256; i++)
	537	palette[i] = i > 0 && i < 16 ? 0xff : 0;
	538	info->pseudo_palette = palette;
fabdbf2f BP	539	info->screen_base = (char __force __iomem *)fb_bitmap;
	540	info->fbops = &picolcdfb_ops;
	541	info->var = picolcdfb_var;
	542	info->fix = picolcdfb_fix;
	543	info->fix.smem_len = PICOLCDFB_SIZE*8;
	544	info->fix.smem_start = (unsigned long)fb_bitmap;
	545	info->par = data;
	546	info->flags = FBINFO_FLAG_DEFAULT;
	547
	548	data->fb_vbitmap = fb_vbitmap;
	549	data->fb_bitmap = fb_bitmap;
	550	data->fb_bpp = picolcdfb_var.bits_per_pixel;
	551	error = picolcd_fb_reset(data, 1);
	552	if (error) {
	553	dev_err(dev, "failed to configure display\n");
	554	goto err_cleanup;
	555	}
	556	error = device_create_file(dev, &dev_attr_fb_update_rate);
	557	if (error) {
	558	dev_err(dev, "failed to create sysfs attributes\n");
	559	goto err_cleanup;
	560	}
	561	fb_deferred_io_init(info);
	562	data->fb_info = info;
	563	error = register_framebuffer(info);
	564	if (error) {
	565	dev_err(dev, "failed to register framebuffer\n");
	566	goto err_sysfs;
	567	}
	568	/* schedule first output of framebuffer */
	569	data->fb_force = 1;
	570	schedule_delayed_work(&info->deferred_work, 0);
	571	return 0;
	572
	573	err_sysfs:
	574	fb_deferred_io_cleanup(info);
	575	device_remove_file(dev, &dev_attr_fb_update_rate);
	576	err_cleanup:
	577	data->fb_vbitmap = NULL;
	578	data->fb_bitmap = NULL;
	579	data->fb_bpp = 0;
	580	data->fb_info = NULL;
	581
	582	err_nomem:
	583	framebuffer_release(info);
	584	vfree(fb_bitmap);
	585	kfree(fb_vbitmap);
	586	return error;
	587	}
	588
	589	void picolcd_exit_framebuffer(struct picolcd_data *data)
	590	{
	591	struct fb_info *info = data->fb_info;
	592	u8 *fb_vbitmap = data->fb_vbitmap;
	593
	594	if (!info)
	595	return;
	596
	597	device_remove_file(&data->hdev->dev, &dev_attr_fb_update_rate);
9966c37c	598	info->par = NULL;
fabdbf2f BP	599	unregister_framebuffer(info);
	600	data->fb_vbitmap = NULL;
	601	data->fb_bitmap = NULL;
	602	data->fb_bpp = 0;
	603	data->fb_info = NULL;
	604	kfree(fb_vbitmap);
	605	}