From 05e59e5fb0064c97a1c10921ecd549f2d4a58565 Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Wed, 09 Oct 2024 06:14:40 +0000
Subject: [PATCH] add REDIRECT

---
 kernel/drivers/video/fbdev/smscufx.c |  124 +++++++++++++++++++++++++----------------
 1 files changed, 75 insertions(+), 49 deletions(-)

diff --git a/kernel/drivers/video/fbdev/smscufx.c b/kernel/drivers/video/fbdev/smscufx.c
index 22b606a..b3295cd 100644
--- a/kernel/drivers/video/fbdev/smscufx.c
+++ b/kernel/drivers/video/fbdev/smscufx.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * smscufx.c -- Framebuffer driver for SMSC UFX USB controller
  *
@@ -5,10 +6,6 @@
  * Copyright (C) 2009 Roberto De Ioris <roberto@unbit.it>
  * Copyright (C) 2009 Jaya Kumar <jayakumar.lkml@gmail.com>
  * Copyright (C) 2009 Bernie Thompson <bernie@plugable.com>
- *
- * This file is subject to the terms and conditions of the GNU General Public
- * License v2. See the file COPYING in the main directory of this archive for
- * more details.
  *
  * Based on udlfb, with work from Florian Echtler, Henrik Bjerregaard Pedersen,
  * and others.
@@ -100,7 +97,6 @@
 	struct kref kref;
 	int fb_count;
 	bool virtualized; /* true when physical usb device not present */
-	struct delayed_work free_framebuffer_work;
 	atomic_t usb_active; /* 0 = update virtual buffer, but no usb traffic */
 	atomic_t lost_pixels; /* 1 = a render op failed. Need screen refresh */
 	u8 *edid; /* null until we read edid from hw or get from sysfs */
@@ -139,6 +135,8 @@
 static int ufx_submit_urb(struct ufx_data *dev, struct urb * urb, size_t len);
 static int ufx_alloc_urb_list(struct ufx_data *dev, int count, size_t size);
 static void ufx_free_urb_list(struct ufx_data *dev);
+
+static DEFINE_MUTEX(disconnect_mutex);
 
 /* reads a control register */
 static int ufx_reg_read(struct ufx_data *dev, u32 index, u32 *data)
@@ -1073,9 +1071,13 @@
 	if (user == 0 && !console)
 		return -EBUSY;
 
+	mutex_lock(&disconnect_mutex);
+
 	/* If the USB device is gone, we don't accept new opens */
-	if (dev->virtualized)
+	if (dev->virtualized) {
+		mutex_unlock(&disconnect_mutex);
 		return -ENODEV;
+	}
 
 	dev->fb_count++;
 
@@ -1099,6 +1101,8 @@
 	pr_debug("open /dev/fb%d user=%d fb_info=%p count=%d",
 		info->node, user, info, dev->fb_count);
 
+	mutex_unlock(&disconnect_mutex);
+
 	return 0;
 }
 
@@ -1111,14 +1115,23 @@
 {
 	struct ufx_data *dev = container_of(kref, struct ufx_data, kref);
 
-	/* this function will wait for all in-flight urbs to complete */
-	if (dev->urbs.count > 0)
-		ufx_free_urb_list(dev);
-
-	pr_debug("freeing ufx_data %p", dev);
-
 	kfree(dev);
 }
+
+static void ufx_ops_destory(struct fb_info *info)
+{
+	struct ufx_data *dev = info->par;
+	int node = info->node;
+
+	/* Assume info structure is freed after this point */
+	framebuffer_release(info);
+
+	pr_debug("fb_info for /dev/fb%d has been freed", node);
+
+	/* release reference taken by kref_init in probe() */
+	kref_put(&dev->kref, ufx_free);
+}
+
 
 static void ufx_release_urb_work(struct work_struct *work)
 {
@@ -1128,14 +1141,9 @@
 	up(&unode->dev->urbs.limit_sem);
 }
 
-static void ufx_free_framebuffer_work(struct work_struct *work)
+static void ufx_free_framebuffer(struct ufx_data *dev)
 {
-	struct ufx_data *dev = container_of(work, struct ufx_data,
-					    free_framebuffer_work.work);
 	struct fb_info *info = dev->info;
-	int node = info->node;
-
-	unregister_framebuffer(info);
 
 	if (info->cmap.len != 0)
 		fb_dealloc_cmap(&info->cmap);
@@ -1146,11 +1154,6 @@
 	fb_destroy_modelist(&info->modelist);
 
 	dev->info = NULL;
-
-	/* Assume info structure is freed after this point */
-	framebuffer_release(info);
-
-	pr_debug("fb_info for /dev/fb%d has been freed", node);
 
 	/* ref taken in probe() as part of registering framebfufer */
 	kref_put(&dev->kref, ufx_free);
@@ -1163,23 +1166,26 @@
 {
 	struct ufx_data *dev = info->par;
 
+	mutex_lock(&disconnect_mutex);
+
 	dev->fb_count--;
 
 	/* We can't free fb_info here - fbmem will touch it when we return */
 	if (dev->virtualized && (dev->fb_count == 0))
-		schedule_delayed_work(&dev->free_framebuffer_work, HZ);
+		ufx_free_framebuffer(dev);
 
 	if ((dev->fb_count == 0) && (info->fbdefio)) {
 		fb_deferred_io_cleanup(info);
 		kfree(info->fbdefio);
 		info->fbdefio = NULL;
-		info->fbops->fb_mmap = ufx_ops_mmap;
 	}
 
 	pr_debug("released /dev/fb%d user=%d count=%d",
 		  info->node, user, dev->fb_count);
 
 	kref_put(&dev->kref, ufx_free);
+
+	mutex_unlock(&disconnect_mutex);
 
 	return 0;
 }
@@ -1272,7 +1278,7 @@
 	return 0;
 }
 
-static struct fb_ops ufx_ops = {
+static const struct fb_ops ufx_ops = {
 	.owner = THIS_MODULE,
 	.fb_read = fb_sys_read,
 	.fb_write = ufx_ops_write,
@@ -1287,6 +1293,7 @@
 	.fb_blank = ufx_ops_blank,
 	.fb_check_var = ufx_ops_check_var,
 	.fb_set_par = ufx_ops_set_par,
+	.fb_destroy = ufx_ops_destory,
 };
 
 /* Assumes &info->lock held by caller
@@ -1614,7 +1621,7 @@
 	struct usb_device *usbdev;
 	struct ufx_data *dev;
 	struct fb_info *info;
-	int retval;
+	int retval = -ENOMEM;
 	u32 id_rev, fpga_rev;
 
 	/* usb initialization */
@@ -1646,7 +1653,7 @@
 
 	if (!ufx_alloc_urb_list(dev, WRITES_IN_FLIGHT, MAX_TRANSFER)) {
 		dev_err(dev->gdev, "ufx_alloc_urb_list failed\n");
-		goto e_nomem;
+		goto put_ref;
 	}
 
 	/* We don't register a new USB class. Our client interface is fbdev */
@@ -1655,24 +1662,20 @@
 	info = framebuffer_alloc(0, &usbdev->dev);
 	if (!info) {
 		dev_err(dev->gdev, "framebuffer_alloc failed\n");
-		goto e_nomem;
+		goto free_urb_list;
 	}
 
 	dev->info = info;
 	info->par = dev;
 	info->pseudo_palette = dev->pseudo_palette;
 	info->fbops = &ufx_ops;
+	INIT_LIST_HEAD(&info->modelist);
 
 	retval = fb_alloc_cmap(&info->cmap, 256, 0);
 	if (retval < 0) {
 		dev_err(dev->gdev, "fb_alloc_cmap failed %x\n", retval);
 		goto destroy_modedb;
 	}
-
-	INIT_DELAYED_WORK(&dev->free_framebuffer_work,
-			  ufx_free_framebuffer_work);
-
-	INIT_LIST_HEAD(&info->modelist);
 
 	retval = ufx_reg_read(dev, 0x3000, &id_rev);
 	check_warn_goto_error(retval, "error %d reading 0x3000 register from device", retval);
@@ -1703,22 +1706,34 @@
 	check_warn_goto_error(retval, "unable to find common mode for display and adapter");
 
 	retval = ufx_reg_set_bits(dev, 0x4000, 0x00000001);
-	check_warn_goto_error(retval, "error %d enabling graphics engine", retval);
+	if (retval < 0) {
+		dev_err(dev->gdev, "error %d enabling graphics engine", retval);
+		goto setup_modes;
+	}
 
 	/* ready to begin using device */
 	atomic_set(&dev->usb_active, 1);
 
 	dev_dbg(dev->gdev, "checking var");
 	retval = ufx_ops_check_var(&info->var, info);
-	check_warn_goto_error(retval, "error %d ufx_ops_check_var", retval);
+	if (retval < 0) {
+		dev_err(dev->gdev, "error %d ufx_ops_check_var", retval);
+		goto reset_active;
+	}
 
 	dev_dbg(dev->gdev, "setting par");
 	retval = ufx_ops_set_par(info);
-	check_warn_goto_error(retval, "error %d ufx_ops_set_par", retval);
+	if (retval < 0) {
+		dev_err(dev->gdev, "error %d ufx_ops_set_par", retval);
+		goto reset_active;
+	}
 
 	dev_dbg(dev->gdev, "registering framebuffer");
 	retval = register_framebuffer(info);
-	check_warn_goto_error(retval, "error %d register_framebuffer", retval);
+	if (retval < 0) {
+		dev_err(dev->gdev, "error %d register_framebuffer", retval);
+		goto reset_active;
+	}
 
 	dev_info(dev->gdev, "SMSC UDX USB device /dev/fb%d attached. %dx%d resolution."
 		" Using %dK framebuffer memory\n", info->node,
@@ -1726,28 +1741,34 @@
 
 	return 0;
 
-error:
-	fb_dealloc_cmap(&info->cmap);
-destroy_modedb:
+reset_active:
+	atomic_set(&dev->usb_active, 0);
+setup_modes:
 	fb_destroy_modedb(info->monspecs.modedb);
 	vfree(info->screen_base);
 	fb_destroy_modelist(&info->modelist);
+error:
+	fb_dealloc_cmap(&info->cmap);
+destroy_modedb:
 	framebuffer_release(info);
+free_urb_list:
+	if (dev->urbs.count > 0)
+		ufx_free_urb_list(dev);
 put_ref:
 	kref_put(&dev->kref, ufx_free); /* ref for framebuffer */
 	kref_put(&dev->kref, ufx_free); /* last ref from kref_init */
 	return retval;
-
-e_nomem:
-	retval = -ENOMEM;
-	goto put_ref;
 }
 
 static void ufx_usb_disconnect(struct usb_interface *interface)
 {
 	struct ufx_data *dev;
+	struct fb_info *info;
+
+	mutex_lock(&disconnect_mutex);
 
 	dev = usb_get_intfdata(interface);
+	info = dev->info;
 
 	pr_debug("USB disconnect starting\n");
 
@@ -1761,12 +1782,17 @@
 
 	/* if clients still have us open, will be freed on last close */
 	if (dev->fb_count == 0)
-		schedule_delayed_work(&dev->free_framebuffer_work, 0);
+		ufx_free_framebuffer(dev);
 
-	/* release reference taken by kref_init in probe() */
-	kref_put(&dev->kref, ufx_free);
+	/* this function will wait for all in-flight urbs to complete */
+	if (dev->urbs.count > 0)
+		ufx_free_urb_list(dev);
 
-	/* consider ufx_data freed */
+	pr_debug("freeing ufx_data %p", dev);
+
+	unregister_framebuffer(info);
+
+	mutex_unlock(&disconnect_mutex);
 }
 
 static struct usb_driver ufx_driver = {

--
Gitblit v1.6.2