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staging: comedi: ni_mio_common: Cleans up/clarifies ni_ao_cmd

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This patch implements ni_ao_cmd much more closely organized like NI MHDDK
examples and DAQ-STC pseudo-code.  Adds comments with some more specific
references to the DAQ-STC.

For stop_src==TRIG_NONE (continuous output mode of entire buffer), the
count for the UC counter was corrected to represent the maximum count
possible (0xffffff).  Prior behavior for stop_src=TRIG_NONE did not
actually follow the DAQ-STC.  Furthermore, stop_src==TRIG_NONE now
correctly uses code specialized for either m-series or e-series devices.

It should be noted that stop_src==TRIG_NONE does _not_ with this patch
(or with prior behavior in ni_mio_common) actually implement true
continuous output.  Rather, the output is simply configured to operate as a
single buffer output, but where the buffer is as large as is possible with
NI-STC hardware.

Signed-off-by: Spencer E. Olson <olsonse@umich.edu>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Spencer E. Olson 2016-01-27 14:28:27 -07:00 committed by Greg Kroah-Hartman
parent d2a6c32a22
commit 080e6795cb
1 changed files with 322 additions and 129 deletions
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425
drivers/staging/comedi/drivers/ni_mio_common.c
View File

@ -2912,42 +2912,68 @@ static int ni_ao_inttrig(struct comedi_device *dev,
return 0;
}
static int ni_ao_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
/*
* begin ni_ao_cmd.
* Organized similar to NI-STC and MHDDK examples.
* ni_ao_cmd is broken out into configuration sub-routines for clarity.
*/
static void ni_ao_cmd_personalize(struct comedi_device *dev,
const struct comedi_cmd *cmd)
{
const struct ni_board_struct *board = dev->board_ptr;
struct ni_private *devpriv = dev->private;
const struct comedi_cmd *cmd = &s->async->cmd;
int bits;
int i;
unsigned trigvar;
unsigned val;
if (dev->irq == 0) {
dev_err(dev->class_dev, "cannot run command without an irq\n");
return -EIO;
}
unsigned bits;
ni_stc_writew(dev, NISTC_RESET_AO_CFG_START, NISTC_RESET_REG);
ni_stc_writew(dev, NISTC_AO_CMD1_DISARM, NISTC_AO_CMD1_REG);
bits =
/* fast CPU interface--only eseries */
/* ((slow CPU interface) ? 0 : AO_Fast_CPU) | */
NISTC_AO_PERSONAL_BC_SRC_SEL |
0 /* (use_original_pulse ? 0 : NISTC_AO_PERSONAL_UPDATE_TIMEBASE) */ |
/*
* FIXME: start setting following bit when appropriate. Need to
* determine whether board is E4 or E1.
* FROM MHHDK:
* if board is E4 or E1
* Set bit "NISTC_AO_PERSONAL_UPDATE_PW" to 0
* else
* set it to 1
*/
NISTC_AO_PERSONAL_UPDATE_PW |
/* FIXME: when should we set following bit to zero? */
NISTC_AO_PERSONAL_TMRDACWR_PW |
(board->ao_fifo_depth ?
NISTC_AO_PERSONAL_FIFO_ENA : NISTC_AO_PERSONAL_DMA_PIO_CTRL)
;
#if 0
/*
* FIXME:
* add something like ".has_individual_dacs = 0" to ni_board_struct
* since, as F Hess pointed out, not all in m series have singles. not
* sure if e-series all have duals...
*/
if (devpriv->is_6xxx) {
ni_ao_win_outw(dev, NI611X_AO_MISC_CLEAR_WG,
NI611X_AO_MISC_REG);
/*
* F Hess: windows driver does not set NISTC_AO_PERSONAL_NUM_DAC bit for
* 6281, verified with bus analyzer.
*/
if (devpriv->is_m_series)
bits |= NISTC_AO_PERSONAL_NUM_DAC;
#endif
ni_stc_writew(dev, bits, NISTC_AO_PERSONAL_REG);
bits = 0;
for (i = 0; i < cmd->chanlist_len; i++) {
int chan;
ni_stc_writew(dev, NISTC_RESET_AO_CFG_END, NISTC_RESET_REG);
}
chan = CR_CHAN(cmd->chanlist[i]);
bits |= 1 << chan;
ni_ao_win_outw(dev, chan, NI611X_AO_WAVEFORM_GEN_REG);
}
ni_ao_win_outw(dev, bits, NI611X_AO_TIMED_REG);
}
static void ni_ao_cmd_set_trigger(struct comedi_device *dev,
const struct comedi_cmd *cmd)
{
struct ni_private *devpriv = dev->private;
ni_ao_config_chanlist(dev, s, cmd->chanlist, cmd->chanlist_len, 1);
ni_stc_writew(dev, NISTC_RESET_AO_CFG_START, NISTC_RESET_REG);
/* sync */
if (cmd->stop_src == TRIG_NONE) {
devpriv->ao_mode1 |= NISTC_AO_MODE1_CONTINUOUS;
devpriv->ao_mode1 &= ~NISTC_AO_MODE1_TRIGGER_ONCE;
@ -2957,179 +2983,346 @@ static int ni_ao_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
}
ni_stc_writew(dev, devpriv->ao_mode1, NISTC_AO_MODE1_REG);
val = devpriv->ao_trigger_select;
{
unsigned int trigsel = devpriv->ao_trigger_select;
switch (cmd->start_src) {
case TRIG_INT:
case TRIG_NOW:
val &= ~(NISTC_AO_TRIG_START1_POLARITY |
trigsel &= ~(NISTC_AO_TRIG_START1_POLARITY |
NISTC_AO_TRIG_START1_SEL_MASK);
val |= NISTC_AO_TRIG_START1_EDGE |
trigsel |= NISTC_AO_TRIG_START1_EDGE |
NISTC_AO_TRIG_START1_SYNC;
break;
case TRIG_EXT:
val = NISTC_AO_TRIG_START1_SEL(CR_CHAN(cmd->start_arg) + 1);
if (cmd->start_arg & CR_INVERT) {
/* 0=active high, 1=active low. see daq-stc 3-24 (p186) */
val |= NISTC_AO_TRIG_START1_POLARITY;
}
if (cmd->start_arg & CR_EDGE) {
trigsel = NISTC_AO_TRIG_START1_SEL(
CR_CHAN(cmd->start_arg) + 1);
if (cmd->start_arg & CR_INVERT)
/*
* 0=active high, 1=active low.
* see daq-stc 3-24 (p186)
*/
trigsel |= NISTC_AO_TRIG_START1_POLARITY;
if (cmd->start_arg & CR_EDGE)
/* 0=edge detection disabled, 1=enabled */
val |= NISTC_AO_TRIG_START1_EDGE;
}
ni_stc_writew(dev, devpriv->ao_trigger_select,
NISTC_AO_TRIG_SEL_REG);
trigsel |= NISTC_AO_TRIG_START1_EDGE;
break;
default:
BUG();
break;
}
devpriv->ao_trigger_select = val;
ni_stc_writew(dev, devpriv->ao_trigger_select, NISTC_AO_TRIG_SEL_REG);
devpriv->ao_trigger_select = trigsel;
ni_stc_writew(dev, devpriv->ao_trigger_select,
NISTC_AO_TRIG_SEL_REG);
}
/* AO_Delayed_START1 = 0, we do not support delayed start...yet */
/* sync */
/* select DA_START1 as PFI6/AO_START1 when configured as an output */
devpriv->ao_mode3 &= ~NISTC_AO_MODE3_TRIG_LEN;
ni_stc_writew(dev, devpriv->ao_mode3, NISTC_AO_MODE3_REG);
ni_stc_writew(dev, NISTC_RESET_AO_CFG_END, NISTC_RESET_REG);
}
static void ni_ao_cmd_set_counters(struct comedi_device *dev,
const struct comedi_cmd *cmd)
{
struct ni_private *devpriv = dev->private;
/* Not supporting 'waveform staging' or 'local buffer with pauses' */
ni_stc_writew(dev, NISTC_RESET_AO_CFG_START, NISTC_RESET_REG);
/*
* This relies on ao_mode1/(Trigger_Once | Continuous) being set in
* set_trigger above. It is unclear whether we really need to re-write
* this register with these values. The mhddk examples for e-series
* show writing this in both places, but the examples for m-series show
* a single write in the set_counters function (here).
*/
ni_stc_writew(dev, devpriv->ao_mode1, NISTC_AO_MODE1_REG);
/* sync (upload number of buffer iterations -1) */
/* indicate that we want to use BC_Load_A_Register as the source */
devpriv->ao_mode2 &= ~NISTC_AO_MODE2_BC_INIT_LOAD_SRC;
ni_stc_writew(dev, devpriv->ao_mode2, NISTC_AO_MODE2_REG);
if (cmd->stop_src == TRIG_NONE)
ni_stc_writel(dev, 0xffffff, NISTC_AO_BC_LOADA_REG);
else
ni_stc_writel(dev, 0, NISTC_AO_BC_LOADA_REG);
/*
* if the BC_TC interrupt is still issued in spite of UC, BC, UI
* ignoring BC_TC, then we will need to find a way to ignore that
* interrupt in continuous mode.
*/
ni_stc_writel(dev, 0, NISTC_AO_BC_LOADA_REG); /* iter once */
/* sync (issue command to load number of buffer iterations -1) */
ni_stc_writew(dev, NISTC_AO_CMD1_BC_LOAD, NISTC_AO_CMD1_REG);
/* sync (upload number of updates in buffer) */
/* indicate that we want to use UC_Load_A_Register as the source */
devpriv->ao_mode2 &= ~NISTC_AO_MODE2_UC_INIT_LOAD_SRC;
ni_stc_writew(dev, devpriv->ao_mode2, NISTC_AO_MODE2_REG);
switch (cmd->stop_src) {
case TRIG_COUNT:
{
/*
* Current behavior is to configure the maximum update count
* possible when continuous output mode is requested.
*/
unsigned int stop_arg = cmd->stop_src == TRIG_COUNT ?
(cmd->stop_arg & 0xffffff) : 0xffffff;
if (devpriv->is_m_series) {
/* this is how the NI example code does it for m-series boards, verified correct with 6259 */
ni_stc_writel(dev, cmd->stop_arg - 1,
NISTC_AO_UC_LOADA_REG);
/*
* this is how the NI example code does it for m-series
* boards, verified correct with 6259
*/
ni_stc_writel(dev, stop_arg - 1, NISTC_AO_UC_LOADA_REG);
/* sync (issue cmd to load number of updates in MISB) */
ni_stc_writew(dev, NISTC_AO_CMD1_UC_LOAD,
NISTC_AO_CMD1_REG);
} else {
ni_stc_writel(dev, cmd->stop_arg,
NISTC_AO_UC_LOADA_REG);
ni_stc_writel(dev, stop_arg, NISTC_AO_UC_LOADA_REG);
/* sync (issue cmd to load number of updates in MISB) */
ni_stc_writew(dev, NISTC_AO_CMD1_UC_LOAD,
NISTC_AO_CMD1_REG);
ni_stc_writel(dev, cmd->stop_arg - 1,
NISTC_AO_UC_LOADA_REG);
/*
* sync (upload number of updates-1 in MISB)
* --eseries only?
*/
ni_stc_writel(dev, stop_arg - 1, NISTC_AO_UC_LOADA_REG);
}
break;
case TRIG_NONE:
ni_stc_writel(dev, 0xffffff, NISTC_AO_UC_LOADA_REG);
ni_stc_writew(dev, NISTC_AO_CMD1_UC_LOAD, NISTC_AO_CMD1_REG);
ni_stc_writel(dev, 0xffffff, NISTC_AO_UC_LOADA_REG);
break;
default:
ni_stc_writel(dev, 0, NISTC_AO_UC_LOADA_REG);
ni_stc_writew(dev, NISTC_AO_CMD1_UC_LOAD, NISTC_AO_CMD1_REG);
ni_stc_writel(dev, cmd->stop_arg, NISTC_AO_UC_LOADA_REG);
}
devpriv->ao_mode1 &= ~(NISTC_AO_MODE1_UPDATE_SRC_MASK |
ni_stc_writew(dev, NISTC_RESET_AO_CFG_END, NISTC_RESET_REG);
}
static void ni_ao_cmd_set_update(struct comedi_device *dev,
const struct comedi_cmd *cmd)
{
struct ni_private *devpriv = dev->private;
ni_stc_writew(dev, NISTC_RESET_AO_CFG_START, NISTC_RESET_REG);
/*
* zero out these bit fields to be set below. Does an ao-reset do this
* automatically?
*/
devpriv->ao_mode1 &= ~(
NISTC_AO_MODE1_UI_SRC_MASK |
NISTC_AO_MODE1_UPDATE_SRC_POLARITY |
NISTC_AO_MODE1_UI_SRC_POLARITY);
NISTC_AO_MODE1_UI_SRC_POLARITY |
NISTC_AO_MODE1_UPDATE_SRC_MASK |
NISTC_AO_MODE1_UPDATE_SRC_POLARITY
);
switch (cmd->scan_begin_src) {
case TRIG_TIMER:
devpriv->ao_cmd2 &= ~NISTC_AO_CMD2_BC_GATE_ENA;
trigvar =
ni_ns_to_timer(dev, cmd->scan_begin_arg,
/*
* NOTE: there are several other ways of configuring internal
* updates, but we'll only support one for now: using
* AO_IN_TIMEBASE, w/o waveform staging, w/o a delay between
* START1 and first update, and also w/o local buffer mode w/
* pauses.
*/
/*
* This is already done above:
* devpriv->ao_mode1 &= ~(
* // set UPDATE_Source to UI_TC:
* NISTC_AO_MODE1_UPDATE_SRC_MASK |
* // set UPDATE_Source_Polarity to rising (required?)
* NISTC_AO_MODE1_UPDATE_SRC_POLARITY |
* // set UI_Source to AO_IN_TIMEBASE1:
* NISTC_AO_MODE1_UI_SRC_MASK |
* // set UI_Source_Polarity to rising (required?)
* NISTC_AO_MODE1_UI_SRC_POLARITY
* );
*/
/*
* TODO: use ao_ui_clock_source to allow all possible signals
* to be routed to UI_Source_Select. See tSTC.h for
* eseries/ni67xx and tMSeries.h for mseries.
*/
{
unsigned trigvar = ni_ns_to_timer(dev,
cmd->scan_begin_arg,
CMDF_ROUND_NEAREST);
/*
* Wait N TB3 ticks after the start trigger before
* clocking(N must be >=2).
*/
/* following line: 2-1 per STC */
ni_stc_writel(dev, 1, NISTC_AO_UI_LOADA_REG);
ni_stc_writew(dev, NISTC_AO_CMD1_UI_LOAD, NISTC_AO_CMD1_REG);
ni_stc_writel(dev, trigvar, NISTC_AO_UI_LOADA_REG);
ni_stc_writew(dev, NISTC_AO_CMD1_UI_LOAD,
NISTC_AO_CMD1_REG);
/* following line: N-1 per STC */
ni_stc_writel(dev, trigvar - 1, NISTC_AO_UI_LOADA_REG);
}
break;
case TRIG_EXT:
devpriv->ao_mode1 |=
NISTC_AO_MODE1_UPDATE_SRC(cmd->scan_begin_arg);
/* FIXME: assert scan_begin_arg != 0, ret failure otherwise */
devpriv->ao_cmd2 |= NISTC_AO_CMD2_BC_GATE_ENA;
devpriv->ao_mode1 |= NISTC_AO_MODE1_UPDATE_SRC(
CR_CHAN(cmd->scan_begin_arg));
if (cmd->scan_begin_arg & CR_INVERT)
devpriv->ao_mode1 |= NISTC_AO_MODE1_UPDATE_SRC_POLARITY;
devpriv->ao_cmd2 |= NISTC_AO_CMD2_BC_GATE_ENA;
break;
default:
BUG();
break;
}
ni_stc_writew(dev, devpriv->ao_cmd2, NISTC_AO_CMD2_REG);
ni_stc_writew(dev, devpriv->ao_mode1, NISTC_AO_MODE1_REG);
devpriv->ao_mode2 &= ~(NISTC_AO_MODE2_UI_RELOAD_MODE(3) |
NISTC_AO_MODE2_UI_INIT_LOAD_SRC);
ni_stc_writew(dev, devpriv->ao_mode2, NISTC_AO_MODE2_REG);
if (cmd->scan_end_arg > 1) {
devpriv->ao_mode1 |= NISTC_AO_MODE1_MULTI_CHAN;
ni_stc_writew(dev,
NISTC_AO_OUT_CTRL_CHANS(cmd->scan_end_arg - 1) |
NISTC_AO_OUT_CTRL_UPDATE_SEL_HIGHZ,
NISTC_AO_OUT_CTRL_REG);
} else {
unsigned bits;
devpriv->ao_mode1 &= ~NISTC_AO_MODE1_MULTI_CHAN;
bits = NISTC_AO_OUT_CTRL_UPDATE_SEL_HIGHZ;
if (devpriv->is_m_series || devpriv->is_6xxx) {
bits |= NISTC_AO_OUT_CTRL_CHANS(0);
} else {
bits |=
NISTC_AO_OUT_CTRL_CHANS(CR_CHAN(cmd->chanlist[0]));
}
ni_stc_writew(dev, bits, NISTC_AO_OUT_CTRL_REG);
}
ni_stc_writew(dev, devpriv->ao_mode1, NISTC_AO_MODE1_REG);
/* Configure DAQ-STC for Timed update mode */
devpriv->ao_cmd1 |= NISTC_AO_CMD1_DAC1_UPDATE_MODE |
NISTC_AO_CMD1_DAC0_UPDATE_MODE;
/* We are not using UPDATE2-->don't have to set DACx_Source_Select */
ni_stc_writew(dev, devpriv->ao_cmd1, NISTC_AO_CMD1_REG);
ni_stc_writew(dev, NISTC_RESET_AO_CFG_END, NISTC_RESET_REG);
}
static void ni_ao_cmd_set_channels(struct comedi_device *dev,
struct comedi_subdevice *s)
{
struct ni_private *devpriv = dev->private;
const struct comedi_cmd *cmd = &s->async->cmd;
unsigned bits = 0;
ni_stc_writew(dev, NISTC_RESET_AO_CFG_START, NISTC_RESET_REG);
if (devpriv->is_6xxx) {
unsigned int i;
bits = 0;
for (i = 0; i < cmd->chanlist_len; ++i) {
int chan = CR_CHAN(cmd->chanlist[i]);
bits |= 1 << chan;
ni_ao_win_outw(dev, chan, NI611X_AO_WAVEFORM_GEN_REG);
}
ni_ao_win_outw(dev, bits, NI611X_AO_TIMED_REG);
}
ni_ao_config_chanlist(dev, s, cmd->chanlist, cmd->chanlist_len, 1);
if (cmd->scan_end_arg > 1) {
devpriv->ao_mode1 |= NISTC_AO_MODE1_MULTI_CHAN;
bits = NISTC_AO_OUT_CTRL_CHANS(cmd->scan_end_arg - 1)
| NISTC_AO_OUT_CTRL_UPDATE_SEL_HIGHZ;
} else {
devpriv->ao_mode1 &= ~NISTC_AO_MODE1_MULTI_CHAN;
bits = NISTC_AO_OUT_CTRL_UPDATE_SEL_HIGHZ;
if (devpriv->is_m_series | devpriv->is_6xxx)
bits |= NISTC_AO_OUT_CTRL_CHANS(0);
else
bits |= NISTC_AO_OUT_CTRL_CHANS(
CR_CHAN(cmd->chanlist[0]));
}
ni_stc_writew(dev, devpriv->ao_mode1, NISTC_AO_MODE1_REG);
ni_stc_writew(dev, bits, NISTC_AO_OUT_CTRL_REG);
ni_stc_writew(dev, NISTC_RESET_AO_CFG_END, NISTC_RESET_REG);
}
static void ni_ao_cmd_set_stop_conditions(struct comedi_device *dev,
const struct comedi_cmd *cmd)
{
struct ni_private *devpriv = dev->private;
ni_stc_writew(dev, NISTC_RESET_AO_CFG_START, NISTC_RESET_REG);
devpriv->ao_mode3 |= NISTC_AO_MODE3_STOP_ON_OVERRUN_ERR;
ni_stc_writew(dev, devpriv->ao_mode3, NISTC_AO_MODE3_REG);
/*
* Since we are not supporting waveform staging, we ignore these errors:
* NISTC_AO_MODE3_STOP_ON_BC_TC_ERR,
* NISTC_AO_MODE3_STOP_ON_BC_TC_TRIG_ERR
*/
ni_stc_writew(dev, NISTC_RESET_AO_CFG_END, NISTC_RESET_REG);
}
static void ni_ao_cmd_set_fifo_mode(struct comedi_device *dev)
{
struct ni_private *devpriv = dev->private;
ni_stc_writew(dev, NISTC_RESET_AO_CFG_START, NISTC_RESET_REG);
devpriv->ao_mode2 &= ~NISTC_AO_MODE2_FIFO_MODE_MASK;
#ifdef PCIDMA
devpriv->ao_mode2 |= NISTC_AO_MODE2_FIFO_MODE_HF_F;
#else
devpriv->ao_mode2 |= NISTC_AO_MODE2_FIFO_MODE_HF;
#endif
/* NOTE: this is where use_onboard_memory=True would be implemented */
devpriv->ao_mode2 &= ~NISTC_AO_MODE2_FIFO_REXMIT_ENA;
ni_stc_writew(dev, devpriv->ao_mode2, NISTC_AO_MODE2_REG);
bits = NISTC_AO_PERSONAL_BC_SRC_SEL |
NISTC_AO_PERSONAL_UPDATE_PW |
NISTC_AO_PERSONAL_TMRDACWR_PW;
if (board->ao_fifo_depth)
bits |= NISTC_AO_PERSONAL_FIFO_ENA;
else
bits |= NISTC_AO_PERSONAL_DMA_PIO_CTRL;
#if 0
/*
* F Hess: windows driver does not set NISTC_AO_PERSONAL_NUM_DAC bit
* for 6281, verified with bus analyzer.
*/
if (devpriv->is_m_series)
bits |= NISTC_AO_PERSONAL_NUM_DAC;
#endif
ni_stc_writew(dev, bits, NISTC_AO_PERSONAL_REG);
/* enable sending of ao dma requests */
/* enable sending of ao fifo requests (dma request) */
ni_stc_writew(dev, NISTC_AO_START_AOFREQ_ENA, NISTC_AO_START_SEL_REG);
ni_stc_writew(dev, NISTC_RESET_AO_CFG_END, NISTC_RESET_REG);
if (cmd->stop_src == TRIG_COUNT) {
ni_stc_writew(dev, NISTC_INTB_ACK_AO_BC_TC,
NISTC_INTB_ACK_REG);
/* we are not supporting boards with virtual fifos */
}
static void ni_ao_cmd_set_interrupts(struct comedi_device *dev,
struct comedi_subdevice *s)
{
if (s->async->cmd.stop_src == TRIG_COUNT)
ni_set_bits(dev, NISTC_INTB_ENA_REG,
NISTC_INTB_ENA_AO_BC_TC, 1);
}
s->async->inttrig = ni_ao_inttrig;
}
static int ni_ao_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
{
struct ni_private *devpriv = dev->private;
const struct comedi_cmd *cmd = &s->async->cmd;
if (dev->irq == 0) {
dev_err(dev->class_dev, "cannot run command without an irq");
return -EIO;
}
/* ni_ao_reset should have already been done */
ni_ao_cmd_personalize(dev, cmd);
/* clearing fifo and preload happens elsewhere */
ni_ao_cmd_set_trigger(dev, cmd);
ni_ao_cmd_set_counters(dev, cmd);
ni_ao_cmd_set_update(dev, cmd);
ni_ao_cmd_set_channels(dev, s);
ni_ao_cmd_set_stop_conditions(dev, cmd);
ni_ao_cmd_set_fifo_mode(dev);
ni_ao_cmd_set_interrupts(dev, s);
/*
* arm(ing) and star(ting) happen in ni_ao_inttrig, which _must_ be
* called for ao commands since 1) TRIG_NOW is not supported and 2) DMA
* must be setup and initially written to before arm/start happen.
*/
return 0;
}
/* end ni_ao_cmd */
static int ni_ao_cmdtest(struct comedi_device *dev, struct comedi_subdevice *s,
struct comedi_cmd *cmd)
{