diff mbox series

[21/21] fbdev: Make registered_fb[] private to fbmem.c

Message ID 20220131210552.482606-22-daniel.vetter@ffwll.ch
State New
Headers show
Series some fbcon patches, mostly locking | expand

Commit Message

Daniel Vetter Jan. 31, 2022, 9:05 p.m. UTC 
Well except when the olpc dcon fbdev driver is enabled, that thing
digs around in there in rather unfixable ways.

Cc oldc_dcon maintainers as fyi.

Cc: Jens Frederich <jfrederich@gmail.com>
Cc: Jon Nettleton <jon.nettleton@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-staging@lists.linux.dev
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Helge Deller <deller@gmx.de>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Zhen Lei <thunder.leizhen@huawei.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Cc: linux-fbdev@vger.kernel.org
Cc: Zheyu Ma <zheyuma97@gmail.com>
Cc: Guenter Roeck <linux@roeck-us.net>
---
 drivers/video/fbdev/core/fbmem.c | 8 ++++++--
 include/linux/fb.h               | 7 +++----
 2 files changed, 9 insertions(+), 6 deletions(-)

Comments

kernel test robot Feb. 1, 2022, 8:13 a.m. UTC | #1 
Hi Daniel,

I love your patch! Yet something to improve:

[auto build test ERROR on tegra-drm/drm/tegra/for-next]
[also build test ERROR on drm/drm-next linus/master v5.17-rc2 next-20220131]
[cannot apply to airlied/drm-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Daniel-Vetter/some-fbcon-patches-mostly-locking/20220201-050907
base:   git://anongit.freedesktop.org/tegra/linux.git drm/tegra/for-next
config: i386-allyesconfig (https://download.01.org/0day-ci/archive/20220201/202202011603.vczWPod7-lkp@intel.com/config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce (this is a W=1 build):
        # https://github.com/0day-ci/linux/commit/245da5ab93b17c0cf1521713d5bde655a72efb65
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Daniel-Vetter/some-fbcon-patches-mostly-locking/20220201-050907
        git checkout 245da5ab93b17c0cf1521713d5bde655a72efb65
        # save the config file to linux build tree
        mkdir build_dir
        make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   drivers/staging/olpc_dcon/olpc_dcon.c: In function 'dcon_probe':
>> drivers/staging/olpc_dcon/olpc_dcon.c:605:6: error: 'num_registered_fb' undeclared (first use in this function); did you mean 'WB_registered'?
     605 |  if (num_registered_fb < 1) {
         |      ^~~~~~~~~~~~~~~~~
         |      WB_registered
   drivers/staging/olpc_dcon/olpc_dcon.c:605:6: note: each undeclared identifier is reported only once for each function it appears in
>> drivers/staging/olpc_dcon/olpc_dcon.c:610:17: error: 'registered_fb' undeclared (first use in this function)
     610 |  dcon->fbinfo = registered_fb[0];
         |                 ^~~~~~~~~~~~~


vim +605 drivers/staging/olpc_dcon/olpc_dcon.c

53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  584  
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  585  static int dcon_probe(struct i2c_client *client, const struct i2c_device_id *id)
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  586  {
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  587  	struct dcon_priv *dcon;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  588  	int rc, i, j;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  589  
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  590  	if (!pdata)
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  591  		return -ENXIO;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  592  
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  593  	dcon = kzalloc(sizeof(*dcon), GFP_KERNEL);
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  594  	if (!dcon)
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  595  		return -ENOMEM;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  596  
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  597  	dcon->client = client;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  598  	init_waitqueue_head(&dcon->waitq);
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  599  	INIT_WORK(&dcon->switch_source, dcon_source_switch);
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  600  	dcon->reboot_nb.notifier_call = dcon_reboot_notify;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  601  	dcon->reboot_nb.priority = -1;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  602  
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  603  	i2c_set_clientdata(client, dcon);
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  604  
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04 @605  	if (num_registered_fb < 1) {
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  606  		dev_err(&client->dev, "DCON driver requires a registered fb\n");
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  607  		rc = -EIO;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  608  		goto einit;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  609  	}
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04 @610  	dcon->fbinfo = registered_fb[0];
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  611  
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  612  	rc = dcon_hw_init(dcon, 1);
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  613  	if (rc)
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  614  		goto einit;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  615  
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  616  	/* Add the DCON device */
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  617  
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  618  	dcon_device = platform_device_alloc("dcon", -1);
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  619  
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  620  	if (!dcon_device) {
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  621  		pr_err("Unable to create the DCON device\n");
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  622  		rc = -ENOMEM;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  623  		goto eirq;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  624  	}
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  625  	rc = platform_device_add(dcon_device);
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  626  	platform_set_drvdata(dcon_device, dcon);
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  627  
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  628  	if (rc) {
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  629  		pr_err("Unable to add the DCON device\n");
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  630  		goto edev;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  631  	}
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  632  
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  633  	for (i = 0; i < ARRAY_SIZE(dcon_device_files); i++) {
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  634  		rc = device_create_file(&dcon_device->dev,
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  635  					&dcon_device_files[i]);
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  636  		if (rc) {
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  637  			dev_err(&dcon_device->dev, "Cannot create sysfs file\n");
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  638  			goto ecreate;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  639  		}
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  640  	}
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  641  
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  642  	dcon->bl_val = dcon_read(dcon, DCON_REG_BRIGHT) & 0x0F;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  643  
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  644  	/* Add the backlight device for the DCON */
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  645  	dcon_bl_props.brightness = dcon->bl_val;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  646  	dcon->bl_dev = backlight_device_register("dcon-bl", &dcon_device->dev,
848d9eabcaebf21 Zebulon McCorkle   2017-11-21  647  						 dcon, &dcon_bl_ops,
848d9eabcaebf21 Zebulon McCorkle   2017-11-21  648  						 &dcon_bl_props);
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  649  	if (IS_ERR(dcon->bl_dev)) {
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  650  		dev_err(&client->dev, "cannot register backlight dev (%ld)\n",
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  651  			PTR_ERR(dcon->bl_dev));
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  652  		dcon->bl_dev = NULL;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  653  	}
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  654  
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  655  	register_reboot_notifier(&dcon->reboot_nb);
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  656  	atomic_notifier_chain_register(&panic_notifier_list, &dcon_panic_nb);
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  657  
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  658  	return 0;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  659  
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  660   ecreate:
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  661  	for (j = 0; j < i; j++)
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  662  		device_remove_file(&dcon_device->dev, &dcon_device_files[j]);
4996b4610767064 Jing Xiangfeng     2020-11-20  663  	platform_device_del(dcon_device);
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  664   edev:
4996b4610767064 Jing Xiangfeng     2020-11-20  665  	platform_device_put(dcon_device);
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  666  	dcon_device = NULL;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  667   eirq:
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  668  	free_irq(DCON_IRQ, dcon);
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  669   einit:
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  670  	kfree(dcon);
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  671  	return rc;
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  672  }
53c43c5ca13328a Greg Kroah-Hartman 2016-04-04  673  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
Geert Uytterhoeven Feb. 4, 2022, 8:30 a.m. UTC | #2 
Hi Daniel,

Thanks for your patch!

On Tue, Feb 1, 2022 at 9:50 PM Daniel Vetter <daniel.vetter@ffwll.ch> wrote:
> Well except when the olpc dcon fbdev driver is enabled, that thing
> digs around in there in rather unfixable ways.

Can't the actual frame buffer driver (which one?) used on olpc export
a pointer to its fb_info?

> --- a/drivers/video/fbdev/core/fbmem.c
> +++ b/drivers/video/fbdev/core/fbmem.c
> @@ -48,10 +48,14 @@
>  static DEFINE_MUTEX(registration_lock);
>
>  struct fb_info *registered_fb[FB_MAX] __read_mostly;
> -EXPORT_SYMBOL(registered_fb);
> -
>  int num_registered_fb __read_mostly;
> +#if IS_ENABLED(CONFIG_OLPC_DCON)

CONFIG_FB_OLPC_DCON (everywhere), cfr. the build failure reported
by the robot.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
diff mbox series

Patch

diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index 904ef1250677..dad6572942fa 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -48,10 +48,14 @@ 
 static DEFINE_MUTEX(registration_lock);
 
 struct fb_info *registered_fb[FB_MAX] __read_mostly;
-EXPORT_SYMBOL(registered_fb);
-
 int num_registered_fb __read_mostly;
+#if IS_ENABLED(CONFIG_OLPC_DCON)
+EXPORT_SYMBOL(registered_fb);
 EXPORT_SYMBOL(num_registered_fb);
+#endif
+#define for_each_registered_fb(i)		\
+	for (i = 0; i < FB_MAX; i++)		\
+		if (!registered_fb[i]) {} else
 
 bool fb_center_logo __read_mostly;
 
diff --git a/include/linux/fb.h b/include/linux/fb.h
index a8a00d2ba1f3..e236817502c2 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -622,16 +622,15 @@  extern int fb_get_color_depth(struct fb_var_screeninfo *var,
 extern int fb_get_options(const char *name, char **option);
 extern int fb_new_modelist(struct fb_info *info);
 
+#if IS_ENABLED(CONFIG_OLPC_DCON)
 extern struct fb_info *registered_fb[FB_MAX];
+
 extern int num_registered_fb;
+#endif
 extern bool fb_center_logo;
 extern int fb_logo_count;
 extern struct class *fb_class;
 
-#define for_each_registered_fb(i)		\
-	for (i = 0; i < FB_MAX; i++)		\
-		if (!registered_fb[i]) {} else
-
 static inline void lock_fb_info(struct fb_info *info)
 {
 	mutex_lock(&info->lock);