[mirror_ubuntu-artful-kernel.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 <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]);

	hid_hw_request(data->hdev, report1, HID_REQ_SET_REPORT);
	hid_hw_request(data->hdev, report2, HID_REQ_SET_REPORT);
	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);
		hid_hw_request(data->hdev, report, HID_REQ_SET_REPORT);
	}
	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;
				hid_hw_wait(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)
			hid_hw_wait(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, 0664, 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;
	unsigned long flags;

	if (!info)
		return;

	device_remove_file(&data->hdev->dev, &dev_attr_fb_update_rate);
	fbdata = info->par;

	/* 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
	23	#include <linux/fb.h>
	24	#include <linux/module.h>
	25
	26	#include "hid-picolcd.h"
	27
	28	/* Framebuffer
	29	*
	30	* The PicoLCD use a Topway LCD module of 256x64 pixel
	31	* This display area is tiled over 4 controllers with 8 tiles
	32	* each. Each tile has 8x64 pixel, each data byte representing
	33	* a 1-bit wide vertical line of the tile.
	34	*
	35	* The display can be updated at a tile granularity.
	36	*
	37	* Chip 1 Chip 2 Chip 3 Chip 4
	38	* +----------------+----------------+----------------+----------------+
	39	* \| Tile 1 \| Tile 1 \| Tile 1 \| Tile 1 \|
	40	* +----------------+----------------+----------------+----------------+
	41	* \| Tile 2 \| Tile 2 \| Tile 2 \| Tile 2 \|
	42	* +----------------+----------------+----------------+----------------+
	43	* ...
	44	* +----------------+----------------+----------------+----------------+
	45	* \| Tile 8 \| Tile 8 \| Tile 8 \| Tile 8 \|
	46	* +----------------+----------------+----------------+----------------+
	47	*/
	48	#define PICOLCDFB_NAME "picolcdfb"
	49	#define PICOLCDFB_WIDTH (256)
	50	#define PICOLCDFB_HEIGHT (64)
	51	#define PICOLCDFB_SIZE (PICOLCDFB_WIDTH * PICOLCDFB_HEIGHT / 8)
	52
	53	#define PICOLCDFB_UPDATE_RATE_LIMIT 10
	54	#define PICOLCDFB_UPDATE_RATE_DEFAULT 2
	55
	56	/* Framebuffer visual structures */
	57	static const struct fb_fix_screeninfo picolcdfb_fix = {
	58	.id = PICOLCDFB_NAME,
	59	.type = FB_TYPE_PACKED_PIXELS,
	60	.visual = FB_VISUAL_MONO01,
	61	.xpanstep = 0,
	62	.ypanstep = 0,
	63	.ywrapstep = 0,
	64	.line_length = PICOLCDFB_WIDTH / 8,
	65	.accel = FB_ACCEL_NONE,
	66	};
	67
	68	static const struct fb_var_screeninfo picolcdfb_var = {
	69	.xres = PICOLCDFB_WIDTH,
	70	.yres = PICOLCDFB_HEIGHT,
	71	.xres_virtual = PICOLCDFB_WIDTH,
	72	.yres_virtual = PICOLCDFB_HEIGHT,
	73	.width = 103,
	74	.height = 26,
	75	.bits_per_pixel = 1,
	76	.grayscale = 1,
	77	.red = {
	78	.offset = 0,
	79	.length = 1,
	80	.msb_right = 0,
	81	},
	82	.green = {
	83	.offset = 0,
	84	.length = 1,
	85	.msb_right = 0,
86	},
87	.blue = {
88	.offset = 0,
89	.length = 1,
90	.msb_right = 0,
91	},
92	.transp = {
93	.offset = 0,
94	.length = 0,
95	.msb_right = 0,
96	},
97	};
98
99	/* Send a given tile to PicoLCD */
16048709 BP	100	static int picolcd_fb_send_tile(struct picolcd_data data, u8 vbitmap,
16048709 BP	101	int chip, int tile)
fabdbf2f	102	{
16048709	103	struct hid_report report1, report2;
fabdbf2f BP	104	unsigned long flags;
	105	u8 *tdata;
	106	int i;
	107
16048709 BP	108	report1 = picolcd_out_report(REPORT_LCD_CMD_DATA, data->hdev);
	109	if (!report1 \|\| report1->maxfield != 1)
	110	return -ENODEV;
	111	report2 = picolcd_out_report(REPORT_LCD_DATA, data->hdev);
	112	if (!report2 \|\| report2->maxfield != 1)
fabdbf2f BP	113	return -ENODEV;
	114
	115	spin_lock_irqsave(&data->lock, flags);
16048709 BP	116	if ((data->status & PICOLCD_FAILED)) {
	117	spin_unlock_irqrestore(&data->lock, flags);
	118	return -ENODEV;
	119	}
fabdbf2f BP	120	hid_set_field(report1->field[0], 0, chip << 2);
	121	hid_set_field(report1->field[0], 1, 0x02);
	122	hid_set_field(report1->field[0], 2, 0x00);
	123	hid_set_field(report1->field[0], 3, 0x00);
	124	hid_set_field(report1->field[0], 4, 0xb8 \| tile);
	125	hid_set_field(report1->field[0], 5, 0x00);
	126	hid_set_field(report1->field[0], 6, 0x00);
	127	hid_set_field(report1->field[0], 7, 0x40);
	128	hid_set_field(report1->field[0], 8, 0x00);
	129	hid_set_field(report1->field[0], 9, 0x00);
	130	hid_set_field(report1->field[0], 10, 32);
	131
	132	hid_set_field(report2->field[0], 0, (chip << 2) \| 0x01);
	133	hid_set_field(report2->field[0], 1, 0x00);
	134	hid_set_field(report2->field[0], 2, 0x00);
	135	hid_set_field(report2->field[0], 3, 32);
	136
16048709	137	tdata = vbitmap + (tile * 4 + chip) * 64;
fabdbf2f BP	138	for (i = 0; i < 64; i++)
	139	if (i < 32)
	140	hid_set_field(report1->field[0], 11 + i, tdata[i]);
	141	else
	142	hid_set_field(report2->field[0], 4 + i - 32, tdata[i]);
	143
d8814272 BT	144	hid_hw_request(data->hdev, report1, HID_REQ_SET_REPORT);
d8814272 BT	145	hid_hw_request(data->hdev, report2, HID_REQ_SET_REPORT);
fabdbf2f BP	146	spin_unlock_irqrestore(&data->lock, flags);
	147	return 0;
	148	}
	149
	150	/* Translate a single tile*/
	151	static int picolcd_fb_update_tile(u8 vbitmap, const u8 bitmap, int bpp,
	152	int chip, int tile)
	153	{
	154	int i, b, changed = 0;
	155	u8 tdata[64];
	156	u8 vdata = vbitmap + (tile 4 + chip) * 64;
	157
	158	if (bpp == 1) {
	159	for (b = 7; b >= 0; b--) {
	160	const u8 bdata = bitmap + tile 256 + chip * 8 + b * 32;
	161	for (i = 0; i < 64; i++) {
	162	tdata[i] <<= 1;
	163	tdata[i] \|= (bdata[i/8] >> (i % 8)) & 0x01;
	164	}
	165	}
	166	} else if (bpp == 8) {
	167	for (b = 7; b >= 0; b--) {
	168	const u8 bdata = bitmap + (tile 256 + chip * 8 + b * 32) * 8;
	169	for (i = 0; i < 64; i++) {
	170	tdata[i] <<= 1;
	171	tdata[i] \|= (bdata[i] & 0x80) ? 0x01 : 0x00;
	172	}
	173	}
	174	} else {
	175	/* Oops, we should never get here! */
	176	WARN_ON(1);
	177	return 0;
	178	}
	179
	180	for (i = 0; i < 64; i++)
	181	if (tdata[i] != vdata[i]) {
	182	changed = 1;
	183	vdata[i] = tdata[i];
	184	}
	185	return changed;
	186	}
	187
	188	void picolcd_fb_refresh(struct picolcd_data *data)
	189	{
	190	if (data->fb_info)
	191	schedule_delayed_work(&data->fb_info->deferred_work, 0);
	192	}
	193
	194	/* Reconfigure LCD display */
	195	int picolcd_fb_reset(struct picolcd_data *data, int clear)
	196	{
	197	struct hid_report *report = picolcd_out_report(REPORT_LCD_CMD, data->hdev);
16048709	198	struct picolcd_fb_data *fbdata = data->fb_info->par;
fabdbf2f BP	199	int i, j;
	200	unsigned long flags;
	201	static const u8 mapcmd[8] = { 0x00, 0x02, 0x00, 0x64, 0x3f, 0x00, 0x64, 0xc0 };
	202
	203	if (!report \|\| report->maxfield != 1)
	204	return -ENODEV;
	205
	206	spin_lock_irqsave(&data->lock, flags);
	207	for (i = 0; i < 4; i++) {
	208	for (j = 0; j < report->field[0]->maxusage; j++)
	209	if (j == 0)
	210	hid_set_field(report->field[0], j, i << 2);
	211	else if (j < sizeof(mapcmd))
	212	hid_set_field(report->field[0], j, mapcmd[j]);
	213	else
	214	hid_set_field(report->field[0], j, 0);
d8814272	215	hid_hw_request(data->hdev, report, HID_REQ_SET_REPORT);
fabdbf2f	216	}
fabdbf2f BP	217	spin_unlock_irqrestore(&data->lock, flags);
fabdbf2f BP	218
16048709 BP	219	if (clear) {
	220	memset(fbdata->vbitmap, 0, PICOLCDFB_SIZE);
	221	memset(fbdata->bitmap, 0, PICOLCDFB_SIZE*fbdata->bpp);
fabdbf2f	222	}
16048709	223	fbdata->force = 1;
fabdbf2f BP	224
fabdbf2f BP	225	/* schedule first output of framebuffer */
16048709 BP	226	if (fbdata->ready)
	227	schedule_delayed_work(&data->fb_info->deferred_work, 0);
	228	else
	229	fbdata->ready = 1;
fabdbf2f BP	230
	231	return 0;
	232	}
	233
	234	/* Update fb_vbitmap from the screen_base and send changed tiles to device */
a93ab849	235	static void picolcd_fb_update(struct fb_info *info)
fabdbf2f BP	236	{
	237	int chip, tile, n;
	238	unsigned long flags;
16048709	239	struct picolcd_fb_data *fbdata = info->par;
a93ab849	240	struct picolcd_data *data;
fabdbf2f	241
a93ab849	242	mutex_lock(&info->lock);
fabdbf2f	243
16048709 BP	244	spin_lock_irqsave(&fbdata->lock, flags);
	245	if (!fbdata->ready && fbdata->picolcd)
	246	picolcd_fb_reset(fbdata->picolcd, 0);
	247	spin_unlock_irqrestore(&fbdata->lock, flags);
fabdbf2f BP	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++)
16048709 BP	258	for (tile = 0; tile < 8; tile++) {
	259	if (!fbdata->force && !picolcd_fb_update_tile(
	260	fbdata->vbitmap, fbdata->bitmap,
	261	fbdata->bpp, chip, tile))
	262	continue;
	263	n += 2;
	264	if (n >= HID_OUTPUT_FIFO_SIZE / 2) {
	265	spin_lock_irqsave(&fbdata->lock, flags);
	266	data = fbdata->picolcd;
	267	spin_unlock_irqrestore(&fbdata->lock, flags);
	268	mutex_unlock(&info->lock);
	269	if (!data)
	270	return;
b7966a4d	271	hid_hw_wait(data->hdev);
16048709 BP	272	mutex_lock(&info->lock);
16048709 BP	273	n = 0;
fabdbf2f	274	}
16048709 BP	275	spin_lock_irqsave(&fbdata->lock, flags);
	276	data = fbdata->picolcd;
	277	spin_unlock_irqrestore(&fbdata->lock, flags);
	278	if (!data \|\| picolcd_fb_send_tile(data,
	279	fbdata->vbitmap, chip, tile))
	280	goto out;
	281	}
	282	fbdata->force = false;
a93ab849	283	if (n) {
16048709 BP	284	spin_lock_irqsave(&fbdata->lock, flags);
	285	data = fbdata->picolcd;
	286	spin_unlock_irqrestore(&fbdata->lock, flags);
a93ab849	287	mutex_unlock(&info->lock);
16048709	288	if (data)
b7966a4d	289	hid_hw_wait(data->hdev);
a93ab849 BP	290	return;
	291	}
	292	out:
	293	mutex_unlock(&info->lock);
fabdbf2f BP	294	}
	295
	296	/* Stub to call the system default and update the image on the picoLCD */
	297	static void picolcd_fb_fillrect(struct fb_info *info,
	298	const struct fb_fillrect *rect)
	299	{
	300	if (!info->par)
	301	return;
	302	sys_fillrect(info, rect);
	303
	304	schedule_delayed_work(&info->deferred_work, 0);
	305	}
	306
	307	/* Stub to call the system default and update the image on the picoLCD */
	308	static void picolcd_fb_copyarea(struct fb_info *info,
	309	const struct fb_copyarea *area)
	310	{
	311	if (!info->par)
	312	return;
	313	sys_copyarea(info, area);
	314
	315	schedule_delayed_work(&info->deferred_work, 0);
	316	}
	317
	318	/* Stub to call the system default and update the image on the picoLCD */
	319	static void picolcd_fb_imageblit(struct fb_info info, const struct fb_image image)
	320	{
	321	if (!info->par)
	322	return;
	323	sys_imageblit(info, image);
	324
	325	schedule_delayed_work(&info->deferred_work, 0);
	326	}
	327
	328	/*
	329	* this is the slow path from userspace. they can seek and write to
	330	* the fb. it's inefficient to do anything less than a full screen draw
	331	*/
	332	static ssize_t picolcd_fb_write(struct fb_info info, const char __user buf,
	333	size_t count, loff_t *ppos)
	334	{
	335	ssize_t ret;
	336	if (!info->par)
	337	return -ENODEV;
	338	ret = fb_sys_write(info, buf, count, ppos);
	339	if (ret >= 0)
	340	schedule_delayed_work(&info->deferred_work, 0);
	341	return ret;
	342	}
	343
	344	static int picolcd_fb_blank(int blank, struct fb_info *info)
	345	{
fabdbf2f BP	346	/* We let fb notification do this for us via lcd/backlight device */
	347	return 0;
	348	}
	349
	350	static void picolcd_fb_destroy(struct fb_info *info)
	351	{
16048709 BP	352	struct picolcd_fb_data *fbdata = info->par;
16048709 BP	353
9966c37c	354	/* make sure no work is deferred */
a93ab849	355	fb_deferred_io_cleanup(info);
fabdbf2f	356
16048709 BP	357	/* No thridparty should ever unregister our framebuffer! */
	358	WARN_ON(fbdata->picolcd != NULL);
	359
9966c37c BP	360	vfree((u8 *)info->fix.smem_start);
9966c37c BP	361	framebuffer_release(info);
fabdbf2f BP	362	}
	363
	364	static int picolcd_fb_check_var(struct fb_var_screeninfo var, struct fb_info info)
	365	{
	366	__u32 bpp = var->bits_per_pixel;
	367	__u32 activate = var->activate;
	368
	369	/* only allow 1/8 bit depth (8-bit is grayscale) */
	370	*var = picolcdfb_var;
	371	var->activate = activate;
	372	if (bpp >= 8) {
	373	var->bits_per_pixel = 8;
	374	var->red.length = 8;
	375	var->green.length = 8;
	376	var->blue.length = 8;
	377	} else {
	378	var->bits_per_pixel = 1;
	379	var->red.length = 1;
	380	var->green.length = 1;
	381	var->blue.length = 1;
	382	}
	383	return 0;
	384	}
	385
	386	static int picolcd_set_par(struct fb_info *info)
	387	{
16048709	388	struct picolcd_fb_data *fbdata = info->par;
fabdbf2f	389	u8 tmp_fb, o_fb;
16048709	390	if (info->var.bits_per_pixel == fbdata->bpp)
fabdbf2f BP	391	return 0;
	392	/* switch between 1/8 bit depths */
	393	if (info->var.bits_per_pixel != 1 && info->var.bits_per_pixel != 8)
	394	return -EINVAL;
	395
16048709	396	o_fb = fbdata->bitmap;
fabdbf2f BP	397	tmp_fb = kmalloc(PICOLCDFB_SIZE*info->var.bits_per_pixel, GFP_KERNEL);
	398	if (!tmp_fb)
	399	return -ENOMEM;
	400
	401	/* translate FB content to new bits-per-pixel */
	402	if (info->var.bits_per_pixel == 1) {
	403	int i, b;
	404	for (i = 0; i < PICOLCDFB_SIZE; i++) {
	405	u8 p = 0;
	406	for (b = 0; b < 8; b++) {
	407	p <<= 1;
	408	p \|= o_fb[i*8+b] ? 0x01 : 0x00;
	409	}
	410	tmp_fb[i] = p;
	411	}
	412	memcpy(o_fb, tmp_fb, PICOLCDFB_SIZE);
	413	info->fix.visual = FB_VISUAL_MONO01;
	414	info->fix.line_length = PICOLCDFB_WIDTH / 8;
	415	} else {
	416	int i;
	417	memcpy(tmp_fb, o_fb, PICOLCDFB_SIZE);
	418	for (i = 0; i < PICOLCDFB_SIZE * 8; i++)
	419	o_fb[i] = tmp_fb[i/8] & (0x01 << (7 - i % 8)) ? 0xff : 0x00;
	420	info->fix.visual = FB_VISUAL_DIRECTCOLOR;
	421	info->fix.line_length = PICOLCDFB_WIDTH;
	422	}
	423
	424	kfree(tmp_fb);
16048709	425	fbdata->bpp = info->var.bits_per_pixel;
fabdbf2f BP	426	return 0;
	427	}
	428
fabdbf2f BP	429	/* Note this can't be const because of struct fb_info definition */
	430	static struct fb_ops picolcdfb_ops = {
	431	.owner = THIS_MODULE,
	432	.fb_destroy = picolcd_fb_destroy,
fabdbf2f BP	433	.fb_read = fb_sys_read,
	434	.fb_write = picolcd_fb_write,
	435	.fb_blank = picolcd_fb_blank,
	436	.fb_fillrect = picolcd_fb_fillrect,
	437	.fb_copyarea = picolcd_fb_copyarea,
	438	.fb_imageblit = picolcd_fb_imageblit,
	439	.fb_check_var = picolcd_fb_check_var,
	440	.fb_set_par = picolcd_set_par,
	441	};
	442
	443
	444	/* Callback from deferred IO workqueue */
	445	static void picolcd_fb_deferred_io(struct fb_info info, struct list_head pagelist)
	446	{
a93ab849	447	picolcd_fb_update(info);
fabdbf2f BP	448	}
	449
	450	static const struct fb_deferred_io picolcd_fb_defio = {
	451	.delay = HZ / PICOLCDFB_UPDATE_RATE_DEFAULT,
	452	.deferred_io = picolcd_fb_deferred_io,
	453	};
	454
	455
	456	/*
	457	* The "fb_update_rate" sysfs attribute
	458	*/
	459	static ssize_t picolcd_fb_update_rate_show(struct device *dev,
	460	struct device_attribute attr, char buf)
	461	{
	462	struct picolcd_data *data = dev_get_drvdata(dev);
16048709 BP	463	struct picolcd_fb_data *fbdata = data->fb_info->par;
16048709 BP	464	unsigned i, fb_update_rate = fbdata->update_rate;
fabdbf2f BP	465	size_t ret = 0;
	466
	467	for (i = 1; i <= PICOLCDFB_UPDATE_RATE_LIMIT; i++)
	468	if (ret >= PAGE_SIZE)
	469	break;
	470	else if (i == fb_update_rate)
	471	ret += snprintf(buf+ret, PAGE_SIZE-ret, "[%u] ", i);
	472	else
	473	ret += snprintf(buf+ret, PAGE_SIZE-ret, "%u ", i);
	474	if (ret > 0)
	475	buf[min(ret, (size_t)PAGE_SIZE)-1] = '\n';
	476	return ret;
	477	}
	478
	479	static ssize_t picolcd_fb_update_rate_store(struct device *dev,
	480	struct device_attribute attr, const char buf, size_t count)
	481	{
	482	struct picolcd_data *data = dev_get_drvdata(dev);
16048709	483	struct picolcd_fb_data *fbdata = data->fb_info->par;
fabdbf2f BP	484	int i;
	485	unsigned u;
	486
	487	if (count < 1 \|\| count > 10)
	488	return -EINVAL;
	489
	490	i = sscanf(buf, "%u", &u);
	491	if (i != 1)
	492	return -EINVAL;
	493
	494	if (u > PICOLCDFB_UPDATE_RATE_LIMIT)
	495	return -ERANGE;
	496	else if (u == 0)
	497	u = PICOLCDFB_UPDATE_RATE_DEFAULT;
	498
16048709 BP	499	fbdata->update_rate = u;
16048709 BP	500	data->fb_info->fbdefio->delay = HZ / fbdata->update_rate;
fabdbf2f BP	501	return count;
	502	}
	503
f92201c3	504	static DEVICE_ATTR(fb_update_rate, 0664, picolcd_fb_update_rate_show,
fabdbf2f BP	505	picolcd_fb_update_rate_store);
	506
	507	/* initialize Framebuffer device */
	508	int picolcd_init_framebuffer(struct picolcd_data *data)
	509	{
	510	struct device *dev = &data->hdev->dev;
	511	struct fb_info *info = NULL;
16048709	512	struct picolcd_fb_data *fbdata = NULL;
fabdbf2f	513	int i, error = -ENOMEM;
fabdbf2f BP	514	u32 *palette;
fabdbf2f BP	515
fabdbf2f	516	/* The extra memory is:
fabdbf2f	517	* - 256*u32 for pseudo_palette
9966c37c	518	* - struct fb_deferred_io
fabdbf2f	519	*/
9966c37c	520	info = framebuffer_alloc(256 * sizeof(u32) +
16048709 BP	521	sizeof(struct fb_deferred_io) +
	522	sizeof(struct picolcd_fb_data) +
	523	PICOLCDFB_SIZE, dev);
fabdbf2f BP	524	if (info == NULL) {
	525	dev_err(dev, "failed to allocate a framebuffer\n");
	526	goto err_nomem;
	527	}
	528
9966c37c BP	529	info->fbdefio = info->par;
9966c37c BP	530	*info->fbdefio = picolcd_fb_defio;
16048709 BP	531	info->par += sizeof(struct fb_deferred_io);
	532	palette = info->par;
	533	info->par += 256 * sizeof(u32);
fabdbf2f BP	534	for (i = 0; i < 256; i++)
	535	palette[i] = i > 0 && i < 16 ? 0xff : 0;
	536	info->pseudo_palette = palette;
fabdbf2f BP	537	info->fbops = &picolcdfb_ops;
	538	info->var = picolcdfb_var;
	539	info->fix = picolcdfb_fix;
	540	info->fix.smem_len = PICOLCDFB_SIZE*8;
fabdbf2f BP	541	info->flags = FBINFO_FLAG_DEFAULT;
fabdbf2f BP	542
16048709 BP	543	fbdata = info->par;
	544	spin_lock_init(&fbdata->lock);
	545	fbdata->picolcd = data;
	546	fbdata->update_rate = PICOLCDFB_UPDATE_RATE_DEFAULT;
	547	fbdata->bpp = picolcdfb_var.bits_per_pixel;
	548	fbdata->force = 1;
	549	fbdata->vbitmap = info->par + sizeof(struct picolcd_fb_data);
	550	fbdata->bitmap = vmalloc(PICOLCDFB_SIZE*8);
	551	if (fbdata->bitmap == NULL) {
	552	dev_err(dev, "can't get a free page for framebuffer\n");
	553	goto err_nomem;
	554	}
	555	info->screen_base = (char __force __iomem *)fbdata->bitmap;
	556	info->fix.smem_start = (unsigned long)fbdata->bitmap;
	557	memset(fbdata->vbitmap, 0xff, PICOLCDFB_SIZE);
	558	data->fb_info = info;
	559
fabdbf2f BP	560	error = picolcd_fb_reset(data, 1);
	561	if (error) {
	562	dev_err(dev, "failed to configure display\n");
	563	goto err_cleanup;
	564	}
16048709	565
fabdbf2f BP	566	error = device_create_file(dev, &dev_attr_fb_update_rate);
	567	if (error) {
	568	dev_err(dev, "failed to create sysfs attributes\n");
	569	goto err_cleanup;
	570	}
16048709	571
fabdbf2f	572	fb_deferred_io_init(info);
fabdbf2f BP	573	error = register_framebuffer(info);
	574	if (error) {
	575	dev_err(dev, "failed to register framebuffer\n");
	576	goto err_sysfs;
	577	}
fabdbf2f BP	578	return 0;
	579
	580	err_sysfs:
fabdbf2f	581	device_remove_file(dev, &dev_attr_fb_update_rate);
16048709	582	fb_deferred_io_cleanup(info);
fabdbf2f	583	err_cleanup:
fabdbf2f BP	584	data->fb_info = NULL;
	585
	586	err_nomem:
16048709 BP	587	if (fbdata)
16048709 BP	588	vfree(fbdata->bitmap);
fabdbf2f	589	framebuffer_release(info);
fabdbf2f BP	590	return error;
	591	}
	592
	593	void picolcd_exit_framebuffer(struct picolcd_data *data)
	594	{
	595	struct fb_info *info = data->fb_info;
1cde501b	596	struct picolcd_fb_data *fbdata;
16048709	597	unsigned long flags;
fabdbf2f	598
1cde501b BP	599	if (!info)
	600	return;
	601
fabdbf2f	602	device_remove_file(&data->hdev->dev, &dev_attr_fb_update_rate);
1cde501b	603	fbdata = info->par;
16048709 BP	604
	605	/* disconnect framebuffer from HID dev */
	606	spin_lock_irqsave(&fbdata->lock, flags);
	607	fbdata->picolcd = NULL;
	608	spin_unlock_irqrestore(&fbdata->lock, flags);
	609
	610	/* make sure there is no running update - thus that fbdata->picolcd
	611	* once obtained under lock is guaranteed not to get free() under
	612	* the feet of the deferred work */
033d9959	613	flush_delayed_work(&info->deferred_work);
16048709 BP	614
16048709 BP	615	data->fb_info = NULL;
fabdbf2f	616	unregister_framebuffer(info);
fabdbf2f	617	}