[PATCH V3 26/29] iio: use parity32 in adxrs450

[PATCH V3 26/29] iio: use parity32 in adxrs450

[zengzhaoxiu]

From: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com>

Signed-off-by: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com>
---
 drivers/iio/gyro/adxrs450.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/gyro/adxrs450.c b/drivers/iio/gyro/adxrs450.c
index a330d42..307f55b 100644
--- a/drivers/iio/gyro/adxrs450.c
+++ b/drivers/iio/gyro/adxrs450.c
@@ -109,7 +109,7 @@ static int adxrs450_spi_read_reg_16(struct iio_dev *indio_dev,
 	mutex_lock(&st->buf_lock);
 	tx = ADXRS450_READ_DATA | (reg_address << 17);
 
-	if (!(hweight32(tx) & 1))
+	if (!parity32(tx))
 		tx |= ADXRS450_P;
 
 	st->tx = cpu_to_be32(tx);
@@ -145,7 +145,7 @@ static int adxrs450_spi_write_reg_16(struct iio_dev *indio_dev,
 	mutex_lock(&st->buf_lock);
 	tx = ADXRS450_WRITE_DATA | (reg_address << 17) | (val << 1);
 
-	if (!(hweight32(tx) & 1))
+	if (!parity32(tx))
 		tx |= ADXRS450_P;
 
 	st->tx = cpu_to_be32(tx);
-- 
2.5.0

[PATCH V3 00/29] bitops: add parity functions

[zengzhaoxiu]

From: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com>

When I do "grep parity -r linux", I found many parity calculations
distributed in many drivers.

This patch series does:
  1. provide generic and architecture-specific parity calculations
  2. remove drivers' local parity calculations, use bitops' parity
     functions instead
  3. replace "hweightN(x) & 1" with "parityN(x)" to improve readability,
     and improve performance on some CPUs that without popcount support

I did not use GCC's __builtin_parity* functions, based on the following reasons:
  1. I don't know where to identify which version of GCC from the beginning
     supported __builtin_parity for the architecture.
  2. For the architecture that doesn't has popcount instruction, GCC instead use
     "call __paritysi2" (__paritydi2 for 64-bits). So if use __builtin_parity, we must
     provide __paritysi2 and __paritydi2 functions for these architectures.
     Additionally, parity4,8,16 might be "__builtin_parity(x & mask)", but the "& mask"
     operation is totally unnecessary.
  3. For the architecture that has popcount instruction, we do the same things.
  4. For powerpc, sparc, and x86, we do runtime patching to use popcount instruction
     if the CPU support.

I have compiled successfully with x86_64_defconfig, i386_defconfig, pseries_defconfig
and sparc64_defconfig.

Changes to v2:
- Add constant PARITY_MAGIC (proposals by Sam Ravnborg)
- Add include/asm-generic/bitops/popc-parity.h (proposals by Chris Metcalf)
- Tile uses popc-parity.h directly
- Mips uses popc-parity.h if has usable __builtin_popcount
- Add few comments in powerpc's and sparc's parity.S
- X86, remove custom calling convention

Changes to v1:
- Add runtime patching for powerpc, sparc, and x86
- Avr32 use grenric parity too
- Fix error in ssfdc's patch, and add commit message
- Don't change the original code composition of drivers/iio/gyro/adxrs450.c
- Directly assignement to phy_cap.parity in drivers/scsi/isci/phy.c

Regards,

=== diffstat ===

Zhaoxiu Zeng (29):
  bitops: add parity functions
  Include generic parity.h in some architectures' bitops.h
  Add alpha-specific parity functions
  Add blackfin-specific parity functions
  Add ia64-specific parity functions
  Tile and MIPS (if has usable __builtin_popcount) use popcount parity
    functions
  Add powerpc-specific parity functions
  Add sparc-specific parity functions
  Add x86-specific parity functions
  sunrpc: use parity8
  mips: use parity functions in cerr-sb1.c
  bch: use parity32
  media: use parity8 in vivid-vbi-gen.c
  media: use parity functions in saa7115
  input: use parity32 in grip_mp
  input: use parity64 in sidewinder
  input: use parity16 in ams_delta_serio
  scsi: use parity32 in isci's phy
  mtd: use parity16 in ssfdc
  mtd: use parity functions in inftlcore
  crypto: use parity functions in qat_hal
  mtd: use parity16 in sm_ftl
  ethernet: use parity8 in sun/niu.c
  input: use parity8 in pcips2
  input: use parity8 in sa1111ps2
  iio: use parity32 in adxrs450
  serial: use parity32 in max3100
  input: use parity8 in elantech
  ethernet: use parity8 in broadcom/tg3.c

 arch/alpha/include/asm/bitops.h              |  27 +++++
 arch/arc/include/asm/bitops.h                |   1 +
 arch/arm/include/asm/bitops.h                |   1 +
 arch/arm64/include/asm/bitops.h              |   1 +
 arch/avr32/include/asm/bitops.h              |   1 +
 arch/blackfin/include/asm/bitops.h           |  31 ++++++
 arch/c6x/include/asm/bitops.h                |   1 +
 arch/cris/include/asm/bitops.h               |   1 +
 arch/frv/include/asm/bitops.h                |   1 +
 arch/h8300/include/asm/bitops.h              |   1 +
 arch/hexagon/include/asm/bitops.h            |   1 +
 arch/ia64/include/asm/bitops.h               |  31 ++++++
 arch/m32r/include/asm/bitops.h               |   1 +
 arch/m68k/include/asm/bitops.h               |   1 +
 arch/metag/include/asm/bitops.h              |   1 +
 arch/mips/include/asm/bitops.h               |   7 ++
 arch/mips/mm/cerr-sb1.c                      |  67 ++++---------
 arch/mn10300/include/asm/bitops.h            |   1 +
 arch/openrisc/include/asm/bitops.h           |   1 +
 arch/parisc/include/asm/bitops.h             |   1 +
 arch/powerpc/include/asm/bitops.h            |  11 +++
 arch/powerpc/lib/Makefile                    |   2 +-
 arch/powerpc/lib/parity_64.S                 | 142 +++++++++++++++++++++++++++
 arch/powerpc/lib/ppc_ksyms.c                 |   5 +
 arch/s390/include/asm/bitops.h               |   1 +
 arch/sh/include/asm/bitops.h                 |   1 +
 arch/sparc/include/asm/bitops_32.h           |   1 +
 arch/sparc/include/asm/bitops_64.h           |  18 ++++
 arch/sparc/kernel/sparc_ksyms_64.c           |   6 ++
 arch/sparc/lib/Makefile                      |   2 +-
 arch/sparc/lib/parity.S                      | 128 ++++++++++++++++++++++++
 arch/tile/include/asm/bitops.h               |   2 +
 arch/x86/include/asm/arch_hweight.h          |   5 +
 arch/x86/include/asm/arch_parity.h           | 117 ++++++++++++++++++++++
 arch/x86/include/asm/bitops.h                |   4 +-
 arch/xtensa/include/asm/bitops.h             |   1 +
 drivers/crypto/qat/qat_common/qat_hal.c      |  32 ++----
 drivers/iio/gyro/adxrs450.c                  |   4 +-
 drivers/input/joystick/grip_mp.c             |  16 +--
 drivers/input/joystick/sidewinder.c          |  24 +----
 drivers/input/mouse/elantech.c               |  10 +-
 drivers/input/mouse/elantech.h               |   1 -
 drivers/input/serio/ams_delta_serio.c        |   8 +-
 drivers/input/serio/pcips2.c                 |   2 +-
 drivers/input/serio/sa1111ps2.c              |   2 +-
 drivers/media/i2c/saa7115.c                  |  17 +---
 drivers/media/platform/vivid/vivid-vbi-gen.c |   9 +-
 drivers/mtd/inftlcore.c                      |  17 +---
 drivers/mtd/sm_ftl.c                         |   5 +-
 drivers/mtd/ssfdc.c                          |  31 ++----
 drivers/net/ethernet/broadcom/tg3.c          |   6 +-
 drivers/net/ethernet/sun/niu.c               |  10 +-
 drivers/scsi/isci/phy.c                      |  15 +--
 drivers/tty/serial/max3100.c                 |   2 +-
 include/asm-generic/bitops.h                 |   1 +
 include/asm-generic/bitops/arch_parity.h     |  39 ++++++++
 include/asm-generic/bitops/const_parity.h    |  36 +++++++
 include/asm-generic/bitops/parity.h          |   7 ++
 include/asm-generic/bitops/popc-parity.h     |  32 ++++++
 include/linux/bitops.h                       |  10 ++
 lib/bch.c                                    |  14 +--
 net/sunrpc/auth_gss/gss_krb5_keys.c          |   6 +-
 62 files changed, 745 insertions(+), 235 deletions(-)
 create mode 100644 arch/powerpc/lib/parity_64.S
 create mode 100644 arch/sparc/lib/parity.S
 create mode 100644 arch/x86/include/asm/arch_parity.h
 create mode 100644 include/asm-generic/bitops/arch_parity.h
 create mode 100644 include/asm-generic/bitops/const_parity.h
 create mode 100644 include/asm-generic/bitops/parity.h
 create mode 100644 include/asm-generic/bitops/popc-parity.h

-- 
2.5.0

Re: [PATCH V3 26/29] iio: use parity32 in adxrs450

[Jonathan Cameron]

On 14/04/16 04:12, zengzhaoxiu@163.com wrote:
> From: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com>
> 
> Signed-off-by: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>

I did ack the previous version and this seems unchanged,
so please do pick up those Acks and carry them with the
series and it makes it obvious when reviewers need to look
again!

Jonathan
> ---
>  drivers/iio/gyro/adxrs450.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/iio/gyro/adxrs450.c b/drivers/iio/gyro/adxrs450.c
> index a330d42..307f55b 100644
> --- a/drivers/iio/gyro/adxrs450.c
> +++ b/drivers/iio/gyro/adxrs450.c
> @@ -109,7 +109,7 @@ static int adxrs450_spi_read_reg_16(struct iio_dev *indio_dev,
>  	mutex_lock(&st->buf_lock);
>  	tx = ADXRS450_READ_DATA | (reg_address << 17);
>  
> -	if (!(hweight32(tx) & 1))
> +	if (!parity32(tx))
>  		tx |= ADXRS450_P;
>  
>  	st->tx = cpu_to_be32(tx);
> @@ -145,7 +145,7 @@ static int adxrs450_spi_write_reg_16(struct iio_dev *indio_dev,
>  	mutex_lock(&st->buf_lock);
>  	tx = ADXRS450_WRITE_DATA | (reg_address << 17) | (val << 1);
>  
> -	if (!(hweight32(tx) & 1))
> +	if (!parity32(tx))
>  		tx |= ADXRS450_P;
>  
>  	st->tx = cpu_to_be32(tx);
>