[alsa-devel] [PATCH 2/2] sis7019: add support for pre-2.6 kernels
The sis7019 driver uses __ffs(), which is available in 2.6 kernels, but not in most earlier ones. This patches the driver to use a local version assembly version, as the hardware is SiS 55x only (i486/Pentium-ish).
Signed-off-by: David Dillow dave@thedillows.org --- This is against the alsa-driver hg repo. It has been compiled and tested under 2.6.23.
pci/sis7019.patch | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++ pci/Makefile | 3 ++- 2 files changed, 54 insertions(+), 1 deletion(-)
diff -r 9eda190b55c3 pci/Makefile --- a/pci/Makefile Tue Dec 04 12:46:46 2007 +0100 +++ b/pci/Makefile Sat Dec 08 18:45:46 2007 -0500 @@ -10,7 +10,7 @@ include $(SND_TOPDIR)/Makefile.conf #
clean-files := ad1889.c atiixp.c atiixp_modem.c bt87x.c cmipci.c ens1370.c \ - fm801.c intel8x0.c maestro3.c via82xx.c via82xx_modem.c + fm801.c intel8x0.c maestro3.c sis7019.c via82xx.c via82xx_modem.c
obj-$(CONFIG_SND) += pdplus/ asihpi/ oxygen/
@@ -31,5 +31,6 @@ fm801.c: fm801.patch $(SND_TOPDIR)/alsa- fm801.c: fm801.patch $(SND_TOPDIR)/alsa-kernel/pci/fm801.c intel8x0.c: intel8x0.patch $(SND_TOPDIR)/alsa-kernel/pci/intel8x0.c maestro3.c: maestro3.patch $(SND_TOPDIR)/alsa-kernel/pci/maestro3.c +sis7019.c: sis7019.patch $(SND_TOPDIR)/alsa-kernel/pci/sis7019.c via82xx.c: via82xx.patch $(SND_TOPDIR)/alsa-kernel/pci/via82xx.c via82xx_modem.c: via82xx_modem.patch $(SND_TOPDIR)/alsa-kernel/pci/via82xx_modem.c diff -r 9eda190b55c3 pci/sis7019.patch --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/pci/sis7019.patch Sat Dec 08 18:45:46 2007 -0500 @@ -0,0 +1,52 @@ +--- sis7019.c.orig 2007-12-08 18:32:09.000000000 -0500 ++++ sis7019.c 2007-12-08 18:31:35.000000000 -0500 +@@ -31,7 +31,17 @@ + #include <sound/core.h> + #include <sound/ac97_codec.h> + #include <sound/initval.h> +-#include "sis7019.h" ++#include "../alsa-kernel/pci/sis7019.h" ++ ++#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0) ++static inline unsigned long sis_ffs(unsigned long word) ++{ ++ __asm__("bsfl %1,%0" ++ :"=r" (word) ++ :"rm" (word)); ++ return word; ++} ++#endif + + MODULE_AUTHOR("David Dillow dave@thedillows.org"); + MODULE_DESCRIPTION("SiS 7019"); +@@ -290,7 +300,11 @@ + int bit; + + while (status) { ++#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0) ++ bit = sis_ffs(status); ++#else + bit = __ffs(status); ++#endif + status >>= bit + 1; + voice += bit; + sis_update_voice(voice); +@@ -791,9 +805,9 @@ + + /* The following variables are only used if there is a timing channel. + */ +- u32 uninitialized_var(timing_ctrl); +- u32 uninitialized_var(sso_eso); +- u32 uninitialized_var(delta); ++ u32 timing_ctrl = 0; ++ u32 sso_eso = 0; ++ u32 delta = 0; + + /* We rely on the PCM core to ensure that the parameters for this + * substream do not change on us while we're programming the HW. +@@ -1460,3 +1474,5 @@ + + module_init(sis7019_init); + module_exit(sis7019_exit); ++ ++EXPORT_NO_SYMBOLS
Dave Dillow wrote:
The sis7019 driver uses __ffs(), which is available in 2.6 kernels, but not in most earlier ones. This patches the driver to use a local version assembly version, as the hardware is SiS 55x only (i486/Pentium-ish).
++#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0) ++static inline unsigned long sis_ffs(unsigned long word) ++{ ++ __asm__("bsfl %1,%0" ++ :"=r" (word) ++ :"rm" (word)); ++ return word; ++} ++#endif
This should go into alsa-driver/include/adriver.h.
Regards, Clemens
On Mon, 2007-12-10 at 08:53 +0100, Clemens Ladisch wrote:
Dave Dillow wrote:
The sis7019 driver uses __ffs(), which is available in 2.6 kernels, but not in most earlier ones. This patches the driver to use a local version assembly version, as the hardware is SiS 55x only (i486/Pentium-ish).
++#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0) ++static inline unsigned long sis_ffs(unsigned long word) ++{ ++ __asm__("bsfl %1,%0" ++ :"=r" (word) ++ :"rm" (word)); ++ return word; ++} ++#endif
This should go into alsa-driver/include/adriver.h.
I'm not sure -- there's no other inline assembly there, and if I provide an x86 _ffs() fallback, then it'll break on other architectures...
I suppose I could put a generic implementation there, but I'd rather take advantage of the hardware I'm on -- which will always be x86 for this driver.
Dave
Dave Dillow wrote:
On Mon, 2007-12-10 at 08:53 +0100, Clemens Ladisch wrote:
Dave Dillow wrote:
The sis7019 driver uses __ffs(), which is available in 2.6 kernels, but not in most earlier ones. This patches the driver to use a local version assembly version, as the hardware is SiS 55x only (i486/Pentium-ish).
++#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0) ++static inline unsigned long sis_ffs(unsigned long word) ++{ ++ __asm__("bsfl %1,%0" ++ :"=r" (word) ++ :"rm" (word)); ++ return word; ++} ++#endif
This should go into alsa-driver/include/adriver.h.
I'm not sure -- there's no other inline assembly there, and if I provide an x86 _ffs() fallback, then it'll break on other architectures...
It won't break unless another driver actually uses __ffs(), and then we can still add a generic implementation.
Regards, Clemens
At Mon, 10 Dec 2007 15:48:44 +0100, Clemens Ladisch wrote:
Dave Dillow wrote:
On Mon, 2007-12-10 at 08:53 +0100, Clemens Ladisch wrote:
Dave Dillow wrote:
The sis7019 driver uses __ffs(), which is available in 2.6 kernels, but not in most earlier ones. This patches the driver to use a local version assembly version, as the hardware is SiS 55x only (i486/Pentium-ish).
++#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0) ++static inline unsigned long sis_ffs(unsigned long word) ++{ ++ __asm__("bsfl %1,%0" ++ :"=r" (word) ++ :"rm" (word)); ++ return word; ++} ++#endif
This should go into alsa-driver/include/adriver.h.
I'm not sure -- there's no other inline assembly there, and if I provide an x86 _ffs() fallback, then it'll break on other architectures...
It won't break unless another driver actually uses __ffs(), and then we can still add a generic implementation.
Yep, it seems so. The invalid asm codes becomes an error only at assembler -> binary level, so it's harmless unless it's really used in the driver code.
Anyway, uninitialized_var() should be ported to adriver.h as well. Then we'll have a clean sis7019.c in alsa-driver tree, too.
Takashi
On Thu, Dec 13, 2007 at 04:50:56PM +0100, Takashi Iwai wrote:
Yep, it seems so. The invalid asm codes becomes an error only at assembler -> binary level, so it's harmless unless it's really used in the driver code.
Anyway, uninitialized_var() should be ported to adriver.h as well. Then we'll have a clean sis7019.c in alsa-driver tree, too.
I'll do the ffs() as suggested, but I rewrote the area that had the uninitialized_var(), so I don't need them any longer.
Dave
participants (3)
-
Clemens Ladisch -
Dave Dillow -
Takashi Iwai