diff options
author | Jia-Ju Bai <baijiaju1990@gmail.com> | 2018-04-24 12:11:21 -0400 |
---|---|---|
committer | Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> | 2018-04-24 12:11:21 -0400 |
commit | 12f3ac2fb16130e4afcfde986fb97f61cb54eead (patch) | |
tree | db106f43cf3d6f26be808c93913e02e0108b615a | |
parent | 8cad95f56f63a63abab0ff0cb451c0bdd5a885dc (diff) |
video: fbdev: savage: Replace mdelay with usleep_range in savage_init_hw
savage_init_hw() is never called in atomic context.
The call chains ending up at savage_init_hw() are:
[1] savage_init_hw() <- savagefb_probe()
[2] savage_init_hw() <- savagefb_resume()
savagefb_probe() is only set as ".probe" in struct pci_driver.
savagefb_resume) is only set as ".resume" in struct pci_driver.
These functions are not called in atomic context.
Despite never getting called from atomic context, savage_init_hw()
calls mdelay() to busily wait.
This is not necessary and can be replaced with usleep_range to
avoid busy waiting.
This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Cc: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
-rw-r--r-- | drivers/video/fbdev/savage/savagefb_driver.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/video/fbdev/savage/savagefb_driver.c b/drivers/video/fbdev/savage/savagefb_driver.c index c20468362f11..c09d7426cd92 100644 --- a/drivers/video/fbdev/savage/savagefb_driver.c +++ b/drivers/video/fbdev/savage/savagefb_driver.c | |||
@@ -1892,11 +1892,11 @@ static int savage_init_hw(struct savagefb_par *par) | |||
1892 | vga_out8(0x3d4, 0x66, par); | 1892 | vga_out8(0x3d4, 0x66, par); |
1893 | cr66 = vga_in8(0x3d5, par); | 1893 | cr66 = vga_in8(0x3d5, par); |
1894 | vga_out8(0x3d5, cr66 | 0x02, par); | 1894 | vga_out8(0x3d5, cr66 | 0x02, par); |
1895 | mdelay(10); | 1895 | usleep_range(10000, 11000); |
1896 | 1896 | ||
1897 | vga_out8(0x3d4, 0x66, par); | 1897 | vga_out8(0x3d4, 0x66, par); |
1898 | vga_out8(0x3d5, cr66 & ~0x02, par); /* clear reset flag */ | 1898 | vga_out8(0x3d5, cr66 & ~0x02, par); /* clear reset flag */ |
1899 | mdelay(10); | 1899 | usleep_range(10000, 11000); |
1900 | 1900 | ||
1901 | 1901 | ||
1902 | /* | 1902 | /* |
@@ -1906,11 +1906,11 @@ static int savage_init_hw(struct savagefb_par *par) | |||
1906 | vga_out8(0x3d4, 0x3f, par); | 1906 | vga_out8(0x3d4, 0x3f, par); |
1907 | cr3f = vga_in8(0x3d5, par); | 1907 | cr3f = vga_in8(0x3d5, par); |
1908 | vga_out8(0x3d5, cr3f | 0x08, par); | 1908 | vga_out8(0x3d5, cr3f | 0x08, par); |
1909 | mdelay(10); | 1909 | usleep_range(10000, 11000); |
1910 | 1910 | ||
1911 | vga_out8(0x3d4, 0x3f, par); | 1911 | vga_out8(0x3d4, 0x3f, par); |
1912 | vga_out8(0x3d5, cr3f & ~0x08, par); /* clear reset flags */ | 1912 | vga_out8(0x3d5, cr3f & ~0x08, par); /* clear reset flags */ |
1913 | mdelay(10); | 1913 | usleep_range(10000, 11000); |
1914 | 1914 | ||
1915 | /* Savage ramdac speeds */ | 1915 | /* Savage ramdac speeds */ |
1916 | par->numClocks = 4; | 1916 | par->numClocks = 4; |