[linux-2.6-block.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 picolcd_data *data, u8 *vbitmap,
		int chip, int tile)
{
	struct hid_report *report1, *report2;
	unsigned long flags;
	u8 *tdata;
	int i;

	report1 = picolcd_out_report(REPORT_LCD_CMD_DATA, data->hdev);
	if (!report1 || report1->maxfield != 1)
		return -ENODEV;
	report2 = picolcd_out_report(REPORT_LCD_DATA, data->hdev);
	if (!report2 || report2->maxfield != 1)
		return -ENODEV;

	spin_lock_irqsave(&data->lock, flags);
	if ((data->status & PICOLCD_FAILED)) {
		spin_unlock_irqrestore(&data->lock, flags);
		return -ENODEV;
	}
	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 = 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);
	struct picolcd_fb_data *fbdata = data->fb_info->par;
	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);
	}
	spin_unlock_irqrestore(&data->lock, flags);

	if (clear) {
		memset(fbdata->vbitmap, 0, PICOLCDFB_SIZE);
		memset(fbdata->bitmap, 0, PICOLCDFB_SIZE*fbdata->bpp);
	}
	fbdata->force = 1;

	/* schedule first output of framebuffer */
	if (fbdata->ready)
		schedule_delayed_work(&data->fb_info->deferred_work, 0);
	else
		fbdata->ready = 1;

	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_fb_data *fbdata = info->par;
	struct picolcd_data *data;

	mutex_lock(&info->lock);

	spin_lock_irqsave(&fbdata->lock, flags);
	if (!fbdata->ready && fbdata->picolcd)
		picolcd_fb_reset(fbdata->picolcd, 0);
	spin_unlock_irqrestore(&fbdata->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 (!fbdata->force && !picolcd_fb_update_tile(
					fbdata->vbitmap, fbdata->bitmap,
					fbdata->bpp, chip, tile))
				continue;
			n += 2;
			if (n >= HID_OUTPUT_FIFO_SIZE / 2) {
				spin_lock_irqsave(&fbdata->lock, flags);
				data = fbdata->picolcd;
				spin_unlock_irqrestore(&fbdata->lock, flags);
				mutex_unlock(&info->lock);
				if (!data)
					return;
				usbhid_wait_io(data->hdev);
				mutex_lock(&info->lock);
				n = 0;
			}
			spin_lock_irqsave(&fbdata->lock, flags);
			data = fbdata->picolcd;
			spin_unlock_irqrestore(&fbdata->lock, flags);
			if (!data || picolcd_fb_send_tile(data,
					fbdata->vbitmap, chip, tile))
				goto out;
		}
	fbdata->force = false;
	if (n) {
		spin_lock_irqsave(&fbdata->lock, flags);
		data = fbdata->picolcd;
		spin_unlock_irqrestore(&fbdata->lock, flags);
		mutex_unlock(&info->lock);
		if (data)
			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)
{
	/* We let fb notification do this for us via lcd/backlight device */
	return 0;
}

static void picolcd_fb_destroy(struct fb_info *info)
{
	struct picolcd_fb_data *fbdata = info->par;

	/* make sure no work is deferred */
	fb_deferred_io_cleanup(info);

	/* No thridparty should ever unregister our framebuffer! */
	WARN_ON(fbdata->picolcd != NULL);

	vfree((u8 *)info->fix.smem_start);
	framebuffer_release(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_fb_data *fbdata = info->par;
	u8 *tmp_fb, *o_fb;
	if (info->var.bits_per_pixel == fbdata->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   = fbdata->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);
	fbdata->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);
	struct picolcd_fb_data *fbdata = data->fb_info->par;
	unsigned i, fb_update_rate = fbdata->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);
	struct picolcd_fb_data *fbdata = data->fb_info->par;
	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;

	fbdata->update_rate = u;
	data->fb_info->fbdefio->delay = HZ / fbdata->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;
	struct picolcd_fb_data *fbdata = NULL;
	int i, error = -ENOMEM;
	u32 *palette;

	/* The extra memory is:
	 * - 256*u32 for pseudo_palette
	 * - struct fb_deferred_io
	 */
	info = framebuffer_alloc(256 * sizeof(u32) +
			sizeof(struct fb_deferred_io) +
			sizeof(struct picolcd_fb_data) +
			PICOLCDFB_SIZE, 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;
	info->par += sizeof(struct fb_deferred_io);
	palette = info->par;
	info->par += 256 * sizeof(u32);
	for (i = 0; i < 256; i++)
		palette[i] = i > 0 && i < 16 ? 0xff : 0;
	info->pseudo_palette = palette;
	info->fbops = &picolcdfb_ops;
	info->var = picolcdfb_var;
	info->fix = picolcdfb_fix;
	info->fix.smem_len   = PICOLCDFB_SIZE*8;
	info->flags = FBINFO_FLAG_DEFAULT;

	fbdata = info->par;
	spin_lock_init(&fbdata->lock);
	fbdata->picolcd = data;
	fbdata->update_rate = PICOLCDFB_UPDATE_RATE_DEFAULT;
	fbdata->bpp     = picolcdfb_var.bits_per_pixel;
	fbdata->force   = 1;
	fbdata->vbitmap = info->par + sizeof(struct picolcd_fb_data);
	fbdata->bitmap  = vmalloc(PICOLCDFB_SIZE*8);
	if (fbdata->bitmap == NULL) {
		dev_err(dev, "can't get a free page for framebuffer\n");
		goto err_nomem;
	}
	info->screen_base = (char __force __iomem *)fbdata->bitmap;
	info->fix.smem_start = (unsigned long)fbdata->bitmap;
	memset(fbdata->vbitmap, 0xff, PICOLCDFB_SIZE);
	data->fb_info = info;

	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);
	error = register_framebuffer(info);
	if (error) {
		dev_err(dev, "failed to register framebuffer\n");
		goto err_sysfs;
	}
	return 0;

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

err_nomem:
	if (fbdata)
		vfree(fbdata->bitmap);
	framebuffer_release(info);
	return error;
}

void picolcd_exit_framebuffer(struct picolcd_data *data)
{
	struct fb_info *info = data->fb_info;
	struct picolcd_fb_data *fbdata = info->par;
	unsigned long flags;

	device_remove_file(&data->hdev->dev, &dev_attr_fb_update_rate);

	/* disconnect framebuffer from HID dev */
	spin_lock_irqsave(&fbdata->lock, flags);
	fbdata->picolcd = NULL;
	spin_unlock_irqrestore(&fbdata->lock, flags);

	/* make sure there is no running update - thus that fbdata->picolcd
	 * once obtained under lock is guaranteed not to get free() under
	 * the feet of the deferred work */
	flush_delayed_work(&info->deferred_work);

	data->fb_info = NULL;
	unregister_framebuffer(info);
}
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 */
16048709 BP	102	static int picolcd_fb_send_tile(struct picolcd_data data, u8 vbitmap,
16048709 BP	103	int chip, int tile)
fabdbf2f	104	{
16048709	105	struct hid_report report1, report2;
fabdbf2f BP	106	unsigned long flags;
	107	u8 *tdata;
	108	int i;
	109
16048709 BP	110	report1 = picolcd_out_report(REPORT_LCD_CMD_DATA, data->hdev);
	111	if (!report1 \|\| report1->maxfield != 1)
	112	return -ENODEV;
	113	report2 = picolcd_out_report(REPORT_LCD_DATA, data->hdev);
	114	if (!report2 \|\| report2->maxfield != 1)
fabdbf2f BP	115	return -ENODEV;
	116
	117	spin_lock_irqsave(&data->lock, flags);
16048709 BP	118	if ((data->status & PICOLCD_FAILED)) {
	119	spin_unlock_irqrestore(&data->lock, flags);
	120	return -ENODEV;
	121	}
fabdbf2f BP	122	hid_set_field(report1->field[0], 0, chip << 2);
	123	hid_set_field(report1->field[0], 1, 0x02);
	124	hid_set_field(report1->field[0], 2, 0x00);
	125	hid_set_field(report1->field[0], 3, 0x00);
	126	hid_set_field(report1->field[0], 4, 0xb8 \| tile);
	127	hid_set_field(report1->field[0], 5, 0x00);
	128	hid_set_field(report1->field[0], 6, 0x00);
	129	hid_set_field(report1->field[0], 7, 0x40);
	130	hid_set_field(report1->field[0], 8, 0x00);
	131	hid_set_field(report1->field[0], 9, 0x00);
	132	hid_set_field(report1->field[0], 10, 32);
	133
	134	hid_set_field(report2->field[0], 0, (chip << 2) \| 0x01);
	135	hid_set_field(report2->field[0], 1, 0x00);
	136	hid_set_field(report2->field[0], 2, 0x00);
	137	hid_set_field(report2->field[0], 3, 32);
	138
16048709	139	tdata = vbitmap + (tile * 4 + chip) * 64;
fabdbf2f BP	140	for (i = 0; i < 64; i++)
	141	if (i < 32)
	142	hid_set_field(report1->field[0], 11 + i, tdata[i]);
	143	else
	144	hid_set_field(report2->field[0], 4 + i - 32, tdata[i]);
	145
	146	usbhid_submit_report(data->hdev, report1, USB_DIR_OUT);
	147	usbhid_submit_report(data->hdev, report2, USB_DIR_OUT);
	148	spin_unlock_irqrestore(&data->lock, flags);
	149	return 0;
	150	}
	151
	152	/* Translate a single tile*/
	153	static int picolcd_fb_update_tile(u8 vbitmap, const u8 bitmap, int bpp,
	154	int chip, int tile)
	155	{
	156	int i, b, changed = 0;
	157	u8 tdata[64];
	158	u8 vdata = vbitmap + (tile 4 + chip) * 64;
	159
	160	if (bpp == 1) {
	161	for (b = 7; b >= 0; b--) {
	162	const u8 bdata = bitmap + tile 256 + chip * 8 + b * 32;
	163	for (i = 0; i < 64; i++) {
	164	tdata[i] <<= 1;
	165	tdata[i] \|= (bdata[i/8] >> (i % 8)) & 0x01;
	166	}
	167	}
	168	} else if (bpp == 8) {
	169	for (b = 7; b >= 0; b--) {
	170	const u8 bdata = bitmap + (tile 256 + chip * 8 + b * 32) * 8;
	171	for (i = 0; i < 64; i++) {
	172	tdata[i] <<= 1;
	173	tdata[i] \|= (bdata[i] & 0x80) ? 0x01 : 0x00;
	174	}
	175	}
	176	} else {
	177	/* Oops, we should never get here! */
	178	WARN_ON(1);
	179	return 0;
	180	}
	181
	182	for (i = 0; i < 64; i++)
	183	if (tdata[i] != vdata[i]) {
	184	changed = 1;
	185	vdata[i] = tdata[i];
	186	}
	187	return changed;
	188	}
	189
	190	void picolcd_fb_refresh(struct picolcd_data *data)
	191	{
	192	if (data->fb_info)
	193	schedule_delayed_work(&data->fb_info->deferred_work, 0);
	194	}
	195
	196	/* Reconfigure LCD display */
	197	int picolcd_fb_reset(struct picolcd_data *data, int clear)
	198	{
	199	struct hid_report *report = picolcd_out_report(REPORT_LCD_CMD, data->hdev);
16048709	200	struct picolcd_fb_data *fbdata = data->fb_info->par;
fabdbf2f BP	201	int i, j;
	202	unsigned long flags;
	203	static const u8 mapcmd[8] = { 0x00, 0x02, 0x00, 0x64, 0x3f, 0x00, 0x64, 0xc0 };
	204
	205	if (!report \|\| report->maxfield != 1)
	206	return -ENODEV;
	207
	208	spin_lock_irqsave(&data->lock, flags);
	209	for (i = 0; i < 4; i++) {
	210	for (j = 0; j < report->field[0]->maxusage; j++)
	211	if (j == 0)
	212	hid_set_field(report->field[0], j, i << 2);
	213	else if (j < sizeof(mapcmd))
	214	hid_set_field(report->field[0], j, mapcmd[j]);
	215	else
	216	hid_set_field(report->field[0], j, 0);
	217	usbhid_submit_report(data->hdev, report, USB_DIR_OUT);
	218	}
fabdbf2f BP	219	spin_unlock_irqrestore(&data->lock, flags);
fabdbf2f BP	220
16048709 BP	221	if (clear) {
	222	memset(fbdata->vbitmap, 0, PICOLCDFB_SIZE);
	223	memset(fbdata->bitmap, 0, PICOLCDFB_SIZE*fbdata->bpp);
fabdbf2f	224	}
16048709	225	fbdata->force = 1;
fabdbf2f BP	226
fabdbf2f BP	227	/* schedule first output of framebuffer */
16048709 BP	228	if (fbdata->ready)
	229	schedule_delayed_work(&data->fb_info->deferred_work, 0);
	230	else
	231	fbdata->ready = 1;
fabdbf2f BP	232
	233	return 0;
	234	}
	235
	236	/* Update fb_vbitmap from the screen_base and send changed tiles to device */
a93ab849	237	static void picolcd_fb_update(struct fb_info *info)
fabdbf2f BP	238	{
	239	int chip, tile, n;
	240	unsigned long flags;
16048709	241	struct picolcd_fb_data *fbdata = info->par;
a93ab849	242	struct picolcd_data *data;
fabdbf2f	243
a93ab849	244	mutex_lock(&info->lock);
fabdbf2f	245
16048709 BP	246	spin_lock_irqsave(&fbdata->lock, flags);
	247	if (!fbdata->ready && fbdata->picolcd)
	248	picolcd_fb_reset(fbdata->picolcd, 0);
	249	spin_unlock_irqrestore(&fbdata->lock, flags);
fabdbf2f BP	250
	251	/*
	252	* Translate the framebuffer into the format needed by the PicoLCD.
	253	* See display layout above.
	254	* Do this one tile after the other and push those tiles that changed.
	255	*
	256	* Wait for our IO to complete as otherwise we might flood the queue!
	257	*/
	258	n = 0;
	259	for (chip = 0; chip < 4; chip++)
16048709 BP	260	for (tile = 0; tile < 8; tile++) {
	261	if (!fbdata->force && !picolcd_fb_update_tile(
	262	fbdata->vbitmap, fbdata->bitmap,
	263	fbdata->bpp, chip, tile))
	264	continue;
	265	n += 2;
	266	if (n >= HID_OUTPUT_FIFO_SIZE / 2) {
	267	spin_lock_irqsave(&fbdata->lock, flags);
	268	data = fbdata->picolcd;
	269	spin_unlock_irqrestore(&fbdata->lock, flags);
	270	mutex_unlock(&info->lock);
	271	if (!data)
	272	return;
	273	usbhid_wait_io(data->hdev);
	274	mutex_lock(&info->lock);
	275	n = 0;
fabdbf2f	276	}
16048709 BP	277	spin_lock_irqsave(&fbdata->lock, flags);
	278	data = fbdata->picolcd;
	279	spin_unlock_irqrestore(&fbdata->lock, flags);
	280	if (!data \|\| picolcd_fb_send_tile(data,
	281	fbdata->vbitmap, chip, tile))
	282	goto out;
	283	}
	284	fbdata->force = false;
a93ab849	285	if (n) {
16048709 BP	286	spin_lock_irqsave(&fbdata->lock, flags);
	287	data = fbdata->picolcd;
	288	spin_unlock_irqrestore(&fbdata->lock, flags);
a93ab849	289	mutex_unlock(&info->lock);
16048709 BP	290	if (data)
16048709 BP	291	usbhid_wait_io(data->hdev);
a93ab849 BP	292	return;
	293	}
	294	out:
	295	mutex_unlock(&info->lock);
fabdbf2f BP	296	}
	297
	298	/* Stub to call the system default and update the image on the picoLCD */
	299	static void picolcd_fb_fillrect(struct fb_info *info,
	300	const struct fb_fillrect *rect)
	301	{
	302	if (!info->par)
	303	return;
	304	sys_fillrect(info, rect);
	305
	306	schedule_delayed_work(&info->deferred_work, 0);
	307	}
	308
	309	/* Stub to call the system default and update the image on the picoLCD */
	310	static void picolcd_fb_copyarea(struct fb_info *info,
	311	const struct fb_copyarea *area)
	312	{
	313	if (!info->par)
	314	return;
	315	sys_copyarea(info, area);
	316
	317	schedule_delayed_work(&info->deferred_work, 0);
	318	}
	319
	320	/* Stub to call the system default and update the image on the picoLCD */
	321	static void picolcd_fb_imageblit(struct fb_info info, const struct fb_image image)
	322	{
	323	if (!info->par)
	324	return;
	325	sys_imageblit(info, image);
	326
	327	schedule_delayed_work(&info->deferred_work, 0);
	328	}
	329
	330	/*
	331	* this is the slow path from userspace. they can seek and write to
	332	* the fb. it's inefficient to do anything less than a full screen draw
	333	*/
	334	static ssize_t picolcd_fb_write(struct fb_info info, const char __user buf,
	335	size_t count, loff_t *ppos)
	336	{
	337	ssize_t ret;
	338	if (!info->par)
	339	return -ENODEV;
	340	ret = fb_sys_write(info, buf, count, ppos);
	341	if (ret >= 0)
	342	schedule_delayed_work(&info->deferred_work, 0);
	343	return ret;
	344	}
	345
	346	static int picolcd_fb_blank(int blank, struct fb_info *info)
	347	{
fabdbf2f BP	348	/* We let fb notification do this for us via lcd/backlight device */
	349	return 0;
	350	}
	351
	352	static void picolcd_fb_destroy(struct fb_info *info)
	353	{
16048709 BP	354	struct picolcd_fb_data *fbdata = info->par;
16048709 BP	355
9966c37c	356	/* make sure no work is deferred */
a93ab849	357	fb_deferred_io_cleanup(info);
fabdbf2f	358
16048709 BP	359	/* No thridparty should ever unregister our framebuffer! */
	360	WARN_ON(fbdata->picolcd != NULL);
	361
9966c37c BP	362	vfree((u8 *)info->fix.smem_start);
9966c37c BP	363	framebuffer_release(info);
fabdbf2f BP	364	}
	365
	366	static int picolcd_fb_check_var(struct fb_var_screeninfo var, struct fb_info info)
	367	{
	368	__u32 bpp = var->bits_per_pixel;
	369	__u32 activate = var->activate;
	370
	371	/* only allow 1/8 bit depth (8-bit is grayscale) */
	372	*var = picolcdfb_var;
	373	var->activate = activate;
	374	if (bpp >= 8) {
	375	var->bits_per_pixel = 8;
	376	var->red.length = 8;
	377	var->green.length = 8;
	378	var->blue.length = 8;
	379	} else {
	380	var->bits_per_pixel = 1;
	381	var->red.length = 1;
	382	var->green.length = 1;
	383	var->blue.length = 1;
	384	}
	385	return 0;
	386	}
	387
	388	static int picolcd_set_par(struct fb_info *info)
	389	{
16048709	390	struct picolcd_fb_data *fbdata = info->par;
fabdbf2f	391	u8 tmp_fb, o_fb;
16048709	392	if (info->var.bits_per_pixel == fbdata->bpp)
fabdbf2f BP	393	return 0;
	394	/* switch between 1/8 bit depths */
	395	if (info->var.bits_per_pixel != 1 && info->var.bits_per_pixel != 8)
	396	return -EINVAL;
	397
16048709	398	o_fb = fbdata->bitmap;
fabdbf2f BP	399	tmp_fb = kmalloc(PICOLCDFB_SIZE*info->var.bits_per_pixel, GFP_KERNEL);
	400	if (!tmp_fb)
	401	return -ENOMEM;
	402
	403	/* translate FB content to new bits-per-pixel */
	404	if (info->var.bits_per_pixel == 1) {
	405	int i, b;
	406	for (i = 0; i < PICOLCDFB_SIZE; i++) {
	407	u8 p = 0;
	408	for (b = 0; b < 8; b++) {
	409	p <<= 1;
	410	p \|= o_fb[i*8+b] ? 0x01 : 0x00;
	411	}
	412	tmp_fb[i] = p;
	413	}
	414	memcpy(o_fb, tmp_fb, PICOLCDFB_SIZE);
	415	info->fix.visual = FB_VISUAL_MONO01;
	416	info->fix.line_length = PICOLCDFB_WIDTH / 8;
	417	} else {
	418	int i;
	419	memcpy(tmp_fb, o_fb, PICOLCDFB_SIZE);
	420	for (i = 0; i < PICOLCDFB_SIZE * 8; i++)
	421	o_fb[i] = tmp_fb[i/8] & (0x01 << (7 - i % 8)) ? 0xff : 0x00;
	422	info->fix.visual = FB_VISUAL_DIRECTCOLOR;
	423	info->fix.line_length = PICOLCDFB_WIDTH;
	424	}
	425
	426	kfree(tmp_fb);
16048709	427	fbdata->bpp = info->var.bits_per_pixel;
fabdbf2f BP	428	return 0;
	429	}
	430
fabdbf2f BP	431	/* Note this can't be const because of struct fb_info definition */
	432	static struct fb_ops picolcdfb_ops = {
	433	.owner = THIS_MODULE,
	434	.fb_destroy = picolcd_fb_destroy,
fabdbf2f BP	435	.fb_read = fb_sys_read,
	436	.fb_write = picolcd_fb_write,
	437	.fb_blank = picolcd_fb_blank,
	438	.fb_fillrect = picolcd_fb_fillrect,
	439	.fb_copyarea = picolcd_fb_copyarea,
	440	.fb_imageblit = picolcd_fb_imageblit,
	441	.fb_check_var = picolcd_fb_check_var,
	442	.fb_set_par = picolcd_set_par,
	443	};
	444
	445
	446	/* Callback from deferred IO workqueue */
	447	static void picolcd_fb_deferred_io(struct fb_info info, struct list_head pagelist)
	448	{
a93ab849	449	picolcd_fb_update(info);
fabdbf2f BP	450	}
	451
	452	static const struct fb_deferred_io picolcd_fb_defio = {
	453	.delay = HZ / PICOLCDFB_UPDATE_RATE_DEFAULT,
	454	.deferred_io = picolcd_fb_deferred_io,
	455	};
	456
	457
	458	/*
	459	* The "fb_update_rate" sysfs attribute
	460	*/
	461	static ssize_t picolcd_fb_update_rate_show(struct device *dev,
	462	struct device_attribute attr, char buf)
	463	{
	464	struct picolcd_data *data = dev_get_drvdata(dev);
16048709 BP	465	struct picolcd_fb_data *fbdata = data->fb_info->par;
16048709 BP	466	unsigned i, fb_update_rate = fbdata->update_rate;
fabdbf2f BP	467	size_t ret = 0;
	468
	469	for (i = 1; i <= PICOLCDFB_UPDATE_RATE_LIMIT; i++)
	470	if (ret >= PAGE_SIZE)
	471	break;
	472	else if (i == fb_update_rate)
	473	ret += snprintf(buf+ret, PAGE_SIZE-ret, "[%u] ", i);
	474	else
	475	ret += snprintf(buf+ret, PAGE_SIZE-ret, "%u ", i);
	476	if (ret > 0)
	477	buf[min(ret, (size_t)PAGE_SIZE)-1] = '\n';
	478	return ret;
	479	}
	480
	481	static ssize_t picolcd_fb_update_rate_store(struct device *dev,
	482	struct device_attribute attr, const char buf, size_t count)
	483	{
	484	struct picolcd_data *data = dev_get_drvdata(dev);
16048709	485	struct picolcd_fb_data *fbdata = data->fb_info->par;
fabdbf2f BP	486	int i;
	487	unsigned u;
	488
	489	if (count < 1 \|\| count > 10)
	490	return -EINVAL;
	491
	492	i = sscanf(buf, "%u", &u);
	493	if (i != 1)
	494	return -EINVAL;
	495
	496	if (u > PICOLCDFB_UPDATE_RATE_LIMIT)
	497	return -ERANGE;
	498	else if (u == 0)
	499	u = PICOLCDFB_UPDATE_RATE_DEFAULT;
	500
16048709 BP	501	fbdata->update_rate = u;
16048709 BP	502	data->fb_info->fbdefio->delay = HZ / fbdata->update_rate;
fabdbf2f BP	503	return count;
	504	}
	505
	506	static DEVICE_ATTR(fb_update_rate, 0666, picolcd_fb_update_rate_show,
	507	picolcd_fb_update_rate_store);
	508
	509	/* initialize Framebuffer device */
	510	int picolcd_init_framebuffer(struct picolcd_data *data)
	511	{
	512	struct device *dev = &data->hdev->dev;
	513	struct fb_info *info = NULL;
16048709	514	struct picolcd_fb_data *fbdata = NULL;
fabdbf2f	515	int i, error = -ENOMEM;
fabdbf2f BP	516	u32 *palette;
fabdbf2f BP	517
fabdbf2f	518	/* The extra memory is:
fabdbf2f	519	* - 256*u32 for pseudo_palette
9966c37c	520	* - struct fb_deferred_io
fabdbf2f	521	*/
9966c37c	522	info = framebuffer_alloc(256 * sizeof(u32) +
16048709 BP	523	sizeof(struct fb_deferred_io) +
	524	sizeof(struct picolcd_fb_data) +
	525	PICOLCDFB_SIZE, dev);
fabdbf2f BP	526	if (info == NULL) {
	527	dev_err(dev, "failed to allocate a framebuffer\n");
	528	goto err_nomem;
	529	}
	530
9966c37c BP	531	info->fbdefio = info->par;
9966c37c BP	532	*info->fbdefio = picolcd_fb_defio;
16048709 BP	533	info->par += sizeof(struct fb_deferred_io);
	534	palette = info->par;
	535	info->par += 256 * sizeof(u32);
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->fbops = &picolcdfb_ops;
	540	info->var = picolcdfb_var;
	541	info->fix = picolcdfb_fix;
	542	info->fix.smem_len = PICOLCDFB_SIZE*8;
fabdbf2f BP	543	info->flags = FBINFO_FLAG_DEFAULT;
fabdbf2f BP	544
16048709 BP	545	fbdata = info->par;
	546	spin_lock_init(&fbdata->lock);
	547	fbdata->picolcd = data;
	548	fbdata->update_rate = PICOLCDFB_UPDATE_RATE_DEFAULT;
	549	fbdata->bpp = picolcdfb_var.bits_per_pixel;
	550	fbdata->force = 1;
	551	fbdata->vbitmap = info->par + sizeof(struct picolcd_fb_data);
	552	fbdata->bitmap = vmalloc(PICOLCDFB_SIZE*8);
	553	if (fbdata->bitmap == NULL) {
	554	dev_err(dev, "can't get a free page for framebuffer\n");
	555	goto err_nomem;
	556	}
	557	info->screen_base = (char __force __iomem *)fbdata->bitmap;
	558	info->fix.smem_start = (unsigned long)fbdata->bitmap;
	559	memset(fbdata->vbitmap, 0xff, PICOLCDFB_SIZE);
	560	data->fb_info = info;
	561
fabdbf2f BP	562	error = picolcd_fb_reset(data, 1);
	563	if (error) {
	564	dev_err(dev, "failed to configure display\n");
	565	goto err_cleanup;
	566	}
16048709	567
fabdbf2f BP	568	error = device_create_file(dev, &dev_attr_fb_update_rate);
	569	if (error) {
	570	dev_err(dev, "failed to create sysfs attributes\n");
	571	goto err_cleanup;
	572	}
16048709	573
fabdbf2f	574	fb_deferred_io_init(info);
fabdbf2f BP	575	error = register_framebuffer(info);
	576	if (error) {
	577	dev_err(dev, "failed to register framebuffer\n");
	578	goto err_sysfs;
	579	}
fabdbf2f BP	580	return 0;
	581
	582	err_sysfs:
fabdbf2f	583	device_remove_file(dev, &dev_attr_fb_update_rate);
16048709	584	fb_deferred_io_cleanup(info);
fabdbf2f	585	err_cleanup:
fabdbf2f BP	586	data->fb_info = NULL;
	587
	588	err_nomem:
16048709 BP	589	if (fbdata)
16048709 BP	590	vfree(fbdata->bitmap);
fabdbf2f	591	framebuffer_release(info);
fabdbf2f BP	592	return error;
	593	}
	594
	595	void picolcd_exit_framebuffer(struct picolcd_data *data)
	596	{
	597	struct fb_info *info = data->fb_info;
16048709 BP	598	struct picolcd_fb_data *fbdata = info->par;
16048709 BP	599	unsigned long flags;
fabdbf2f BP	600
fabdbf2f BP	601	device_remove_file(&data->hdev->dev, &dev_attr_fb_update_rate);
16048709 BP	602
	603	/* disconnect framebuffer from HID dev */
	604	spin_lock_irqsave(&fbdata->lock, flags);
	605	fbdata->picolcd = NULL;
	606	spin_unlock_irqrestore(&fbdata->lock, flags);
	607
	608	/* make sure there is no running update - thus that fbdata->picolcd
	609	* once obtained under lock is guaranteed not to get free() under
	610	* the feet of the deferred work */
033d9959	611	flush_delayed_work(&info->deferred_work);
16048709 BP	612
16048709 BP	613	data->fb_info = NULL;
fabdbf2f	614	unregister_framebuffer(info);
fabdbf2f	615	}