From 5458f3e7b5a8707a49948857d69b2eb2fa5931ac Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Wed, 23 Jan 2013 12:44:40 -0700 Subject: [PATCH] staging: comedi: addi_apci_3501: introduce apci3501_wait_for_dac() Refactor the code that waits for the DAC to be ready into a helper function. A timeout of some sort should be added to this helper so code the users to expect the error condition. In i_APCI3501_WriteAnalogOutput() just return the error and don't actually write the new value to the DAC. In apci3501_reset() output a dev_warn() that the DAC was not ready. Signed-off-by: H Hartley Sweeten Cc: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- .../comedi/drivers/addi-data/hwdrv_apci3501.c | 21 +++++--------- .../staging/comedi/drivers/addi_apci_3501.c | 29 ++++++++++++------- 2 files changed, 27 insertions(+), 23 deletions(-) diff --git a/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3501.c b/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3501.c index 9739e8b87bea..b057906c7bff 100644 --- a/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3501.c +++ b/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3501.c @@ -136,7 +136,8 @@ static int i_APCI3501_WriteAnalogOutput(struct comedi_device *dev, unsigned int *data) { struct apci3501_private *devpriv = dev->private; - unsigned int ul_Command1 = 0, ul_Channel_no, ul_Polarity, ul_DAC_Ready = 0; + unsigned int ul_Command1 = 0, ul_Channel_no, ul_Polarity; + int ret; ul_Channel_no = CR_CHAN(insn->chanspec); @@ -159,21 +160,15 @@ static int i_APCI3501_WriteAnalogOutput(struct comedi_device *dev, printk("\nIn WriteAnalogOutput :: Not Valid Channel\n"); } /* end if((ul_Channel_no<0)||(ul_Channel_no>7)) */ - ul_DAC_Ready = inl(dev->iobase + APCI3501_AO_CTRL_STATUS_REG); + ret = apci3501_wait_for_dac(dev); + if (ret) + return ret; - while (ul_DAC_Ready == 0) { - ul_DAC_Ready = inl(dev->iobase + APCI3501_AO_CTRL_STATUS_REG); - ul_DAC_Ready = (ul_DAC_Ready >> 8) & 1; - } - - if (ul_DAC_Ready) { -/* Output the Value on the output channels. */ - ul_Command1 = - (unsigned int) ((unsigned int) (ul_Channel_no & 0xFF) | + /* Output the Value on the output channels. */ + ul_Command1 = (unsigned int) ((unsigned int) (ul_Channel_no & 0xFF) | (unsigned int) ((*data << 0x8) & 0x7FFFFF00L) | (unsigned int) (ul_Polarity)); - outl(ul_Command1, dev->iobase + APCI3501_AO_DATA_REG); - } + outl(ul_Command1, dev->iobase + APCI3501_AO_DATA_REG); return insn->n; } diff --git a/drivers/staging/comedi/drivers/addi_apci_3501.c b/drivers/staging/comedi/drivers/addi_apci_3501.c index b4679b24dd7b..906c37a34c37 100644 --- a/drivers/staging/comedi/drivers/addi_apci_3501.c +++ b/drivers/staging/comedi/drivers/addi_apci_3501.c @@ -47,6 +47,17 @@ static struct comedi_lrange apci3501_ao_range = { } }; +static int apci3501_wait_for_dac(struct comedi_device *dev) +{ + unsigned int status; + + do { + status = inl(dev->iobase + APCI3501_AO_CTRL_STATUS_REG); + } while (!(status & APCI3501_AO_STATUS_READY)); + + return 0; +} + #include "addi-data/hwdrv_apci3501.c" static int apci3501_di_insn_bits(struct comedi_device *dev, @@ -209,7 +220,8 @@ static irqreturn_t apci3501_interrupt(int irq, void *d) static int apci3501_reset(struct comedi_device *dev) { int i_Count = 0, i_temp = 0; - unsigned int ul_Command1 = 0, ul_Polarity, ul_DAC_Ready = 0; + unsigned int ul_Command1 = 0, ul_Polarity; + int ret; outl(0x0, dev->iobase + APCI3501_DO_REG); outl(1, dev->iobase + APCI3501_AO_CTRL_STATUS_REG); @@ -217,15 +229,12 @@ static int apci3501_reset(struct comedi_device *dev) ul_Polarity = 0x80000000; for (i_Count = 0; i_Count <= 7; i_Count++) { - ul_DAC_Ready = inl(dev->iobase + APCI3501_AO_CTRL_STATUS_REG); - - while (ul_DAC_Ready == 0) { - ul_DAC_Ready = - inl(dev->iobase + APCI3501_AO_CTRL_STATUS_REG); - ul_DAC_Ready = (ul_DAC_Ready >> 8) & 1; - } - - if (ul_DAC_Ready) { + ret = apci3501_wait_for_dac(dev); + if (ret) { + dev_warn(dev->class_dev, + "%s: DAC not-ready for channel %i\n", + __func__, i_Count); + } else { /* Output the Value on the output channels. */ ul_Command1 = (unsigned int) ((unsigned int) (i_Count & 0xFF) | -- 2.30.2