From 4384aaadc2289cc15a606205e6a897dd524cd0f8 Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Tue, 4 Mar 2014 11:30:15 -0700 Subject: [PATCH] staging: comedi: pcl812: cleanup setup_range_channel() Move this function to remove the need for the forward declaration. Rename it so it has namespace associated with the driver. Remove the unnecessary comedi_subdevice parameter from the function. The hardware does not support analog input channel scanning so the mux and range need to be set before each (*insn_read) and when advancing to the next channel in an async command. Instead of storing the last chan/range in the private data just store the chanspec to determine if the mux and range need to be changed. Refactor pcl812_reset() a bit so we can use the helper function to set the mux and range. Define the bits in the mux register to remove the magic values. Signed-off-by: H Hartley Sweeten Reviewed-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/pcl812.c | 109 +++++++++++------------- 1 file changed, 50 insertions(+), 59 deletions(-) diff --git a/drivers/staging/comedi/drivers/pcl812.c b/drivers/staging/comedi/drivers/pcl812.c index 7e105c872b9..862e3792668 100644 --- a/drivers/staging/comedi/drivers/pcl812.c +++ b/drivers/staging/comedi/drivers/pcl812.c @@ -141,8 +141,11 @@ #define PCL812_DI_MSB_REG 0x07 #define PCL812_STATUS_REG 0x08 #define PCL812_STATUS_DRDY (1 << 5) -#define PCL812_GAIN 9 -#define PCL812_MUX 10 +#define PCL812_RANGE_REG 0x09 +#define PCL812_MUX_REG 0x0a +#define PCL812_MUX_CHAN(x) ((x) << 0) +#define PCL812_MUX_CS0 (1 << 4) +#define PCL812_MUX_CS1 (1 << 5) #define PCL812_MODE 11 #define PCL812_CNTENABLE 10 #define PCL812_SOFTTRIG 12 @@ -500,8 +503,7 @@ static const struct pcl812_board boardtypes[] = { struct pcl812_private { unsigned char dma; /* >0 use dma ( usedDMA channel) */ unsigned char range_correction; /* =1 we must add 1 to range number */ - unsigned char old_chan_reg; /* lastly used chan/gain pair */ - unsigned char old_gain_reg; + unsigned int last_ai_chanspec; unsigned char mode_reg_int; /* there is stored INT number for some card */ unsigned int ai_poll_ptr; /* how many sampes transfer poll */ unsigned int ai_act_scan; /* how many scans we finished */ @@ -524,10 +526,6 @@ struct pcl812_private { unsigned int ai_eos:1; }; -static void setup_range_channel(struct comedi_device *dev, - struct comedi_subdevice *s, - unsigned int rangechan, char wait); - static void pcl812_start_pacer(struct comedi_device *dev, bool load_timers) { struct pcl812_private *devpriv = dev->private; @@ -633,6 +631,41 @@ static void pcl812_ai_setup_next_dma(struct comedi_device *dev, enable_dma(devpriv->dma); } +static void pcl812_ai_set_chan_range(struct comedi_device *dev, + unsigned int chanspec, char wait) +{ + struct pcl812_private *devpriv = dev->private; + unsigned int chan = CR_CHAN(chanspec); + unsigned int range = CR_RANGE(chanspec); + unsigned int mux = 0; + + if (chanspec == devpriv->last_ai_chanspec) + return; + + devpriv->last_ai_chanspec = chanspec; + + if (devpriv->use_mpc508) { + if (devpriv->use_diff) { + mux |= PCL812_MUX_CS0 | PCL812_MUX_CS1; + } else { + if (chan < 8) + mux |= PCL812_MUX_CS0; + else + mux |= PCL812_MUX_CS1; + } + } + + outb(mux | PCL812_MUX_CHAN(chan), dev->iobase + PCL812_MUX_REG); + outb(range + devpriv->range_correction, dev->iobase + PCL812_RANGE_REG); + + if (wait) + /* + * XXX this depends on selected range and can be very long for + * some high gain ranges! + */ + udelay(devpriv->max_812_ai_mode0_rangewait); +} + static void pcl812_ai_clear_eoc(struct comedi_device *dev) { /* writing any value clears the interrupt request */ @@ -761,8 +794,7 @@ static int pcl812_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s) pcl812_start_pacer(dev, false); - /* select first channel and range */ - setup_range_channel(dev, s, cmd->chanlist[0], 1); + pcl812_ai_set_chan_range(dev, cmd->chanlist[0], 1); if (devpriv->dma) { /* check if we can use DMA transfer */ devpriv->ai_dma = 1; @@ -851,7 +883,7 @@ static void pcl812_handle_eoc(struct comedi_device *dev, if (next_chan >= cmd->chanlist_len) next_chan = 0; if (cmd->chanlist[s->async->cur_chan] != cmd->chanlist[next_chan]) - setup_range_channel(dev, s, cmd->chanlist[next_chan], 0); + pcl812_ai_set_chan_range(dev, cmd->chanlist[next_chan], 0); pcl812_ai_next_chan(dev, s); } @@ -956,48 +988,6 @@ static int pcl812_ai_poll(struct comedi_device *dev, struct comedi_subdevice *s) return s->async->buf_write_count - s->async->buf_read_count; } -static void setup_range_channel(struct comedi_device *dev, - struct comedi_subdevice *s, - unsigned int rangechan, char wait) -{ - struct pcl812_private *devpriv = dev->private; - unsigned char chan_reg = CR_CHAN(rangechan); /* normal board */ - /* gain index */ - unsigned char gain_reg = CR_RANGE(rangechan) + - devpriv->range_correction; - - if ((chan_reg == devpriv->old_chan_reg) - && (gain_reg == devpriv->old_gain_reg)) - return; /* we can return, no change */ - - devpriv->old_chan_reg = chan_reg; - devpriv->old_gain_reg = gain_reg; - - if (devpriv->use_mpc508) { - if (devpriv->use_diff) { - chan_reg = chan_reg | 0x30; /* DIFF inputs */ - } else { - if (chan_reg & 0x80) - /* SE inputs 8-15 */ - chan_reg = chan_reg | 0x20; - else - /* SE inputs 0-7 */ - chan_reg = chan_reg | 0x10; - } - } - - outb(chan_reg, dev->iobase + PCL812_MUX); /* select channel */ - outb(gain_reg, dev->iobase + PCL812_GAIN); /* select gain */ - - - if (wait) - /* - * XXX this depends on selected range and can be very long for - * some high gain ranges! - */ - udelay(devpriv->max_812_ai_mode0_rangewait); -} - static int pcl812_ai_cancel(struct comedi_device *dev, struct comedi_subdevice *s) { @@ -1025,8 +1015,7 @@ static int pcl812_ai_insn_read(struct comedi_device *dev, /* select software trigger */ outb(devpriv->mode_reg_int | 1, dev->iobase + PCL812_MODE); - /* select channel and renge */ - setup_range_channel(dev, s, insn->chanspec, 1); + pcl812_ai_set_chan_range(dev, insn->chanspec, 1); for (i = 0; i < insn->n; i++) { pcl812_ai_clear_eoc(dev); @@ -1110,10 +1099,12 @@ static void pcl812_reset(struct comedi_device *dev) const struct pcl812_board *board = comedi_board(dev); struct pcl812_private *devpriv = dev->private; - outb(0, dev->iobase + PCL812_MUX); - outb(0 + devpriv->range_correction, dev->iobase + PCL812_GAIN); - devpriv->old_chan_reg = -1; /* invalidate chain/gain memory */ - devpriv->old_gain_reg = -1; + /* + * Invalidate last_ai_chanspec then set analog input to + * known channel/range. + */ + devpriv->last_ai_chanspec = CR_PACK(16, 0, 0); + pcl812_ai_set_chan_range(dev, CR_PACK(0, 0, 0), 0); switch (board->board_type) { case boardPCL812PG: -- 2.46.0