Re: [PATCH] fbdev: sm712fb: avoid unused function warnings
From: Geert Uytterhoeven <geert@linux-m68k.org>
Date: 2015-11-22 20:51:56
Also in:
linux-arm-kernel, lkml
Hi Arnd, On Fri, Nov 20, 2015 at 10:48 PM, Arnd Bergmann [off-list ref] wrote:
The sm712fb framebuffer driver encloses the power-management functions in #ifdef CONFIG_PM, but the smtcfb_pci_suspend/resume functions are only really used when CONFIG_PM_SLEEP is also set, as a frequent gcc warning shows: fbdev/sm712fb.c:1549:12: warning: 'smtcfb_pci_suspend' defined but not used fbdev/sm712fb.c:1572:12: warning: 'smtcfb_pci_resume' defined but not used The driver also avoids using the SIMPLE_DEV_PM_OPS macro when CONFIG_PM is unset, which is redundant.
Is it? AFAIK there's no dummy of SIMPLE_DEV_PM_OPS() for the !CONFIG_PM case yet. May be a good idea to have, though.
quoted hunk ↗ jump to hunk
This changes the driver to remove the #ifdef and instead mark the functions as __maybe_unused, which is a nicer anyway, as it provides build testing for all the code in all configurations and is harder to get wrong. Signed-off-by: Arnd Bergmann <arnd@arndb.de>diff --git a/drivers/video/fbdev/sm712fb.c b/drivers/video/fbdev/sm712fb.c index 629bfa2d2f51..86ae1d4556fc 100644 --- a/drivers/video/fbdev/sm712fb.c +++ b/drivers/video/fbdev/sm712fb.c@@ -28,9 +28,7 @@ #include <linux/console.h> #include <linux/screen_info.h> -#ifdef CONFIG_PM #include <linux/pm.h> -#endif #include "sm712.h"@@ -1545,8 +1543,7 @@ static void smtcfb_pci_remove(struct pci_dev *pdev) pci_disable_device(pdev); } -#ifdef CONFIG_PM -static int smtcfb_pci_suspend(struct device *device) +static int __maybe_unused smtcfb_pci_suspend(struct device *device) { struct pci_dev *pdev = to_pci_dev(device); struct smtcfb_info *sfb;@@ -1569,7 +1566,7 @@ static int smtcfb_pci_suspend(struct device *device) return 0; } -static int smtcfb_pci_resume(struct device *device) +static int __maybe_unused smtcfb_pci_resume(struct device *device) { struct pci_dev *pdev = to_pci_dev(device); struct smtcfb_info *sfb;@@ -1610,20 +1607,13 @@ static int smtcfb_pci_resume(struct device *device) } static SIMPLE_DEV_PM_OPS(sm7xx_pm_ops, smtcfb_pci_suspend, smtcfb_pci_resume); -#define SM7XX_PM_OPS (&sm7xx_pm_ops) - -#else /* !CONFIG_PM */ - -#define SM7XX_PM_OPS NULL - -#endif /* !CONFIG_PM */ static struct pci_driver smtcfb_driver = { .name = "smtcfb", .id_table = smtcfb_pci_table, .probe = smtcfb_pci_probe, .remove = smtcfb_pci_remove, - .driver.pm = SM7XX_PM_OPS, + .driver.pm = &sm7xx_pm_ops,
Hence now there will always be a struct dev_pm_ops in the binary,
which contains 23 pointers, i.e 92 or 184 bytes.
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