Prelimininary framebuffer driver for Topaz signature pads

driver.diff

diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 1aeb80e52424..c8bd6991339a 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -985,6 +985,12 @@ config HID_ALPS
 	Say Y here if you have a Alps touchpads over i2c-hid or usbhid
 	and want support for its special functionalities.
 
+config HID_TOPAZ
+	tristate "Topaz signature pad HID support"
+	depends on USB_HID
+	---help---
+	Support for Topaz signature pads that communicate over USB HID.
+
 endmenu
 
 endif # HID
diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
index 4d111f23e801..ee45eb6e70c6 100644
--- a/drivers/hid/Makefile
+++ b/drivers/hid/Makefile
@@ -94,6 +94,7 @@ obj-$(CONFIG_HID_SUNPLUS)	+= hid-sunplus.o
 obj-$(CONFIG_HID_GREENASIA)	+= hid-gaff.o
 obj-$(CONFIG_HID_THRUSTMASTER)	+= hid-tmff.o
 obj-$(CONFIG_HID_TIVO)		+= hid-tivo.o
+obj-$(CONFIG_HID_TOPAZ)		+= hid-topaz.o
 obj-$(CONFIG_HID_TOPSEED)	+= hid-topseed.o
 obj-$(CONFIG_HID_TWINHAN)	+= hid-twinhan.o
 obj-$(CONFIG_HID_UCLOGIC)	+= hid-uclogic.o
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index 86c95d30ac80..ed3fd69bb9c1 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -1119,4 +1119,8 @@
 #define USB_VENDOR_ID_UGTIZER			0x2179
 #define USB_DEVICE_ID_UGTIZER_TABLET_GP0610	0x0053
 
+
+#define USB_VENDOR_ID_TOPAZ	    0x06A8
+#define USB_DEVICE_ID_TOPAZ_LBK766  0x0043
+
 #endif
diff --git a/drivers/hid/hid-topaz.c b/drivers/hid/hid-topaz.c
new file mode 100644
index 000000000000..bb7a0af5ed7a
--- /dev/null
+++ b/drivers/hid/hid-topaz.c
@@ -0,0 +1,239 @@
+/*
+ * HID driver for Topaz signature pads
+ *
+ * Copyright (c) 2017 Alyssa Rosenzweig
+ *
+ * Author: Alyssa Rosenzweig <alyssa@rosenzweig.io> 
+ *
+ * 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; either version 2 of the License, or (at your option)
+ * any later version.
+ */
+
+#include <linux/device.h>
+#include <linux/hid.h>
+#include <linux/input.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/fb.h>
+#include <linux/init.h>
+
+#include "hid-ids.h"
+
+// names from Topaz API documentation
+
+#define MODE_CLEAR	    0
+#define MODE_COMPLEMENT	    1
+#define MODE_OPAQUE	    2
+#define MODE_TRANSPARENT    3
+
+static int topaz_send(struct hid_device *dev, u8 *packet, size_t sz)
+{
+	int ret;
+
+	u8 *buf = kmemdup(packet, sz, GFP_KERNEL);
+	if(!buf) 
+		return -ENOMEM;
+
+	if(!dev->ll_driver->output_report)
+		return -ENODEV;
+
+	ret = hid_hw_output_report(dev, buf, sz);
+	kfree(buf);
+
+	return ret;
+}
+
+static int topaz_blit8(struct hid_device *dev, u16 x, u16 y, void* data)
+{
+	u8 packet[11 + 8] = {0xF2, 0x07, 0x02, 0, 0, 0, 0, 0, 8, 0, 8};
+
+	packet[3] = (x & 0xFF00) >> 8;
+	packet[4] = (x & 0x00FF);
+	packet[5] = (y & 0xFF00) >> 8;
+	packet[6] = (y & 0x00FF);
+
+	memcpy(packet + 11, data, 8);
+
+	return topaz_send(dev, packet, sizeof(packet)) & 0;
+}
+
+static int topaz_bitmap(struct hid_device *dev, u16 xpos, u16 ypos, u16 width, u16 height, u8* data)
+{
+	u8 block[8];
+
+	int ret;
+	int x, y, row;
+
+	int awidth = ((width + 7) >> 3) << 3;
+
+	for (x = 0; x < width; x += 8) {
+		for (y = 0; y < height; y += 8) {
+			/* blit 8x8 block */
+
+			memset(block, 0, sizeof(block));
+			for (row = 0; row < 8 && y + row < height; ++row) {
+				block[row] = data[((y + row) * awidth + x) >> 3];
+			}
+
+			ret = topaz_blit8(dev, xpos + x, ypos + y, block);
+
+			if(ret)
+				return ret;
+		}
+	}
+
+	return 0;
+}
+
+static int topaz_rectangle(struct hid_device *dev, u16 x, u16 y, u16 w, u16 h, u8 mode)
+{
+	u8 packet[11] = { 0xFF, 0x12, mode };
+
+	packet[3] = (x & 0xFF00) >> 8;
+	packet[4] = (x & 0x00FF);
+	packet[5] = (y & 0xFF00) >> 8;
+	packet[6] = (y & 0x00FF);
+	packet[7] = (w & 0xFF00) >> 8;
+	packet[8] = (w & 0x00FF);
+	packet[9] = (h & 0xFF00) >> 8;
+	packet[10] = (h & 0x00FF);
+
+	return topaz_send(dev, packet, sizeof(packet));
+}
+
+static int topaz_clear(struct hid_device *dev)
+{
+	return topaz_rectangle(dev, 0, 0, 320, 240, 2);
+}
+
+static int topaz_backlight(struct hid_device *dev, bool on)
+{
+	u8 packet[] = { 0x81, 0x02 | (!on) };
+	return topaz_send(dev, packet, sizeof(packet));
+}
+
+static int topazfb_probe(struct hid_device *dev);
+
+static int topaz_probe(struct hid_device *dev, const struct hid_device_id *id)
+{
+	int ret;
+
+	ret = hid_parse(dev);
+	if(ret)
+		goto done;
+
+	ret = hid_hw_start(dev, HID_CONNECT_DEFAULT);
+	if(ret)
+		goto done;
+
+	ret = hid_hw_open(dev);
+	if(ret)
+		goto done;
+
+	ret = topaz_clear(dev);
+	//if(ret)
+	//	goto done;
+
+	ret = topazfb_probe(dev);
+	if(ret)
+		goto done;
+done:
+	return ret;
+}
+static void topaz_remove(struct hid_device *dev)
+{
+	hid_hw_stop(dev);
+}
+
+static struct fb_fix_screeninfo topazfb_fix = {
+	.id = "topaz",
+	.type = FB_TYPE_PACKED_PIXELS,
+	.visual = FB_VISUAL_MONO01,
+	.xpanstep = 0,
+	.ypanstep = 0,
+	.ywrapstep = 0,
+	.accel = FB_ACCEL_NONE
+};
+
+struct topazfb_par {
+	struct hid_device *hid;
+};
+
+static void topazfb_imageblit(struct fb_info *p, const struct fb_image *image)
+{
+	if(image->depth != 1) {
+		printk("Bad image depth %d\n", image->depth);
+		return;
+	}
+
+	topaz_bitmap(((struct topazfb_par*) p->par)->hid,
+			image->dx, image->dy,
+			image->width, image->height,
+			image->data);
+}
+
+static void topazfb_fillrect(struct fb_info *p, const struct fb_fillrect *region)
+{
+	int mode = region->rop == ROP_XOR ? MODE_COMPLEMENT : MODE_OPAQUE;
+	
+	topaz_rectangle(((struct topazfb_par*) p->par)->hid,
+			region->dx, region->dy,
+			region->width, region->height,
+			mode);
+}
+
+static struct fb_ops topazfb_ops = {
+	.owner = THIS_MODULE,
+	.fb_fillrect = topazfb_fillrect,
+	.fb_imageblit = topazfb_imageblit
+};
+
+static int topazfb_probe(struct hid_device *dev)
+{
+	struct fb_info *info;
+
+	info = framebuffer_alloc(sizeof(struct topazfb_par), NULL);
+
+	struct topazfb_par *par = info->par;
+	par->hid = dev;
+
+	info->fbops = &topazfb_ops;
+	info->fix = topazfb_fix;
+	info->flags = FBINFO_DEFAULT | FBINFO_HWACCEL_IMAGEBLIT;
+	info->screen_base = kmalloc(320*240>>3, GFP_KERNEL);
+
+	info->var.xres = 320;
+	info->var.yres = 240;
+
+	if(register_framebuffer(info) < 0) {
+		return -EINVAL;
+	}
+
+	return 0;
+
+}
+
+static const struct hid_device_id topaz_devices[] = {
+	{ HID_USB_DEVICE(USB_VENDOR_ID_TOPAZ, USB_DEVICE_ID_TOPAZ_LBK766) },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(hid, topaz_devices);
+
+static struct hid_driver topaz_driver = {
+	.name = "topaz",
+	.id_table = topaz_devices,
+	.probe = topaz_probe,
+	.remove = topaz_remove
+};
+
+module_hid_driver(topaz_driver);
+
+MODULE_AUTHOR("Alyssa Rosenzweig <alyssa@rosenzweig.io>");
+MODULE_DESCRIPTION("HID driver for Topaz signature pads");
+MODULE_LICENSE("GPL");