The 10-bit pwm value (2-498) is written by banging 2-bits in the data register.
Refactor this function to remove the need for the union pcmcmdtype and struct pwmbitstype. Signed-off-by: H Hartley Sweeten <hswee...@visionengravers.com> Cc: Ian Abbott <abbo...@mev.co.uk> Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- drivers/staging/comedi/drivers/c6xdigio.c | 41 +++++++++++++------------------ 1 file changed, 17 insertions(+), 24 deletions(-) diff --git a/drivers/staging/comedi/drivers/c6xdigio.c b/drivers/staging/comedi/drivers/c6xdigio.c index 7c2c19f..a9066d6 100644 --- a/drivers/staging/comedi/drivers/c6xdigio.c +++ b/drivers/staging/comedi/drivers/c6xdigio.c @@ -50,18 +50,6 @@ http://robot0.ge.uiuc.edu/~spong/mecha/ #define C6XDIGIO_STATUS_REG 0x01 #define C6XDIGIO_CTRL_REG 0x02 -struct pwmbitstype { - unsigned sb0:2; - unsigned sb1:2; - unsigned sb2:2; - unsigned sb3:2; - unsigned sb4:2; -}; -union pwmcmdtype { - unsigned cmd; /* assuming here that int is 32bit */ - struct pwmbitstype bits; -}; - #define C6XDIGIO_TIME_OUT 20 static int c6xdigio_chk_status(struct comedi_device *dev, unsigned long context) @@ -113,25 +101,30 @@ static void c6xdigio_pwm_init(struct comedi_device *dev) static void c6xdigio_pwm_write(struct comedi_device *dev, unsigned int chan, unsigned int val) { + unsigned int bits; unsigned ppcmd; - union pwmcmdtype pwm; - - pwm.cmd = val; - if (pwm.cmd > 498) - pwm.cmd = 498; - if (pwm.cmd < 2) - pwm.cmd = 2; if (chan == 0) ppcmd = 0x28; else ppcmd = 0x30; - c6xdigio_write_data(dev, ppcmd + pwm.bits.sb0, 0x00); - c6xdigio_write_data(dev, ppcmd + pwm.bits.sb1 + 0x4, 0x80); - c6xdigio_write_data(dev, ppcmd + pwm.bits.sb2, 0x00); - c6xdigio_write_data(dev, ppcmd + pwm.bits.sb3 + 0x4, 0x80); - c6xdigio_write_data(dev, ppcmd + pwm.bits.sb4, 0x00); + if (val > 498) + val = 498; + if (val < 2) + val = 2; + + bits = (val >> 0) & 0x03; + c6xdigio_write_data(dev, ppcmd + bits, 0x00); + bits = (val >> 2) & 0x03; + c6xdigio_write_data(dev, ppcmd + bits + 0x4, 0x80); + bits = (val >> 4) & 0x03; + c6xdigio_write_data(dev, ppcmd + bits, 0x00); + bits = (val >> 6) & 0x03; + c6xdigio_write_data(dev, ppcmd + bits + 0x4, 0x80); + bits = (val >> 8) & 0x03; + c6xdigio_write_data(dev, ppcmd + bits, 0x00); + c6xdigio_write_data(dev, 0x00, 0x80); } -- 1.8.5.2 _______________________________________________ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
