staging: comedi: me4000: simplify ai_prepare()

The ai (*do_cmd_test) validates the trigger sources in Step 2b to ensure
that they are compatible. Save the 'ai_ctrl_mode' that will be used in the
private data so that ai_prepare(), which is called by the ai (*do_cmd),
does not have to recheck the sources in order to figure it out.

Also, tidy up the stop trigger checks so that the ME4000_AI_CTRL_HF_IRQ
bit is set in the common code path.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/comedi/drivers/me4000.c b/drivers/staging/comedi/drivers/me4000.c
index ebc4307..60f62f3 100644 (file)
--- a/drivers/staging/comedi/drivers/me4000.c
+++ b/drivers/staging/comedi/drivers/me4000.c
@@ -163,6 +163,7 @@ broken.
 
 struct me4000_private {
        unsigned long plx_regbase;
+       unsigned int ai_ctrl_mode;
        unsigned int ai_init_ticks;
        unsigned int ai_scan_ticks;
        unsigned int ai_chan_ticks;
@@ -684,59 +685,35 @@ static int ai_prepare(struct comedi_device *dev,
                      struct comedi_subdevice *s,
                      struct comedi_cmd *cmd)
 {
-       unsigned int tmp = 0;
+       struct me4000_private *devpriv = dev->private;
+       unsigned int ctrl;
 
        /* Write timer arguments */
        ai_write_timer(dev);
 
        /* Reset control register */
-       outl(tmp, dev->iobase + ME4000_AI_CTRL_REG);
+       outl(0, dev->iobase + ME4000_AI_CTRL_REG);
 
        /* Start sources */
-       if ((cmd->start_src == TRIG_EXT &&
-            cmd->scan_begin_src == TRIG_TIMER &&
-            cmd->convert_src == TRIG_TIMER) ||
-           (cmd->start_src == TRIG_EXT &&
-            cmd->scan_begin_src == TRIG_FOLLOW &&
-            cmd->convert_src == TRIG_TIMER)) {
-               tmp = ME4000_AI_CTRL_MODE_1 |
-                     ME4000_AI_CTRL_CHANNEL_FIFO |
-                     ME4000_AI_CTRL_DATA_FIFO;
-       } else if (cmd->start_src == TRIG_EXT &&
-                  cmd->scan_begin_src == TRIG_EXT &&
-                  cmd->convert_src == TRIG_TIMER) {
-               tmp = ME4000_AI_CTRL_MODE_2 |
-                     ME4000_AI_CTRL_CHANNEL_FIFO |
-                     ME4000_AI_CTRL_DATA_FIFO;
-       } else if (cmd->start_src == TRIG_EXT &&
-                  cmd->scan_begin_src == TRIG_EXT &&
-                  cmd->convert_src == TRIG_EXT) {
-               tmp = ME4000_AI_CTRL_MODE_0 |
-                     ME4000_AI_CTRL_MODE_1 |
-                     ME4000_AI_CTRL_CHANNEL_FIFO |
-                     ME4000_AI_CTRL_DATA_FIFO;
-       } else {
-               tmp = ME4000_AI_CTRL_MODE_0 |
-                     ME4000_AI_CTRL_CHANNEL_FIFO |
-                     ME4000_AI_CTRL_DATA_FIFO;
-       }
+       ctrl = devpriv->ai_ctrl_mode |
+              ME4000_AI_CTRL_CHANNEL_FIFO |
+              ME4000_AI_CTRL_DATA_FIFO;
 
        /* Stop triggers */
        if (cmd->stop_src == TRIG_COUNT) {
                outl(cmd->chanlist_len * cmd->stop_arg,
                     dev->iobase + ME4000_AI_SAMPLE_COUNTER_REG);
-               tmp |= ME4000_AI_CTRL_HF_IRQ | ME4000_AI_CTRL_SC_IRQ;
+               ctrl |= ME4000_AI_CTRL_SC_IRQ;
        } else if (cmd->stop_src == TRIG_NONE &&
                   cmd->scan_end_src == TRIG_COUNT) {
                outl(cmd->scan_end_arg,
                     dev->iobase + ME4000_AI_SAMPLE_COUNTER_REG);
-               tmp |= ME4000_AI_CTRL_HF_IRQ | ME4000_AI_CTRL_SC_IRQ;
-       } else {
-               tmp |= ME4000_AI_CTRL_HF_IRQ;
+               ctrl |= ME4000_AI_CTRL_SC_IRQ;
        }
+       ctrl |= ME4000_AI_CTRL_HF_IRQ;
 
        /* Write the setup to the control register */
-       outl(tmp, dev->iobase + ME4000_AI_CTRL_REG);
+       outl(ctrl, dev->iobase + ME4000_AI_CTRL_REG);
 
        /* Write the channel list */
        me4000_ai_write_chanlist(dev, s, cmd);
@@ -800,21 +777,28 @@ static int me4000_ai_do_cmd_test(struct comedi_device *dev,
        if (cmd->start_src == TRIG_NOW &&
            cmd->scan_begin_src == TRIG_TIMER &&
            cmd->convert_src == TRIG_TIMER) {
+               devpriv->ai_ctrl_mode = ME4000_AI_CTRL_MODE_0;
        } else if (cmd->start_src == TRIG_NOW &&
                   cmd->scan_begin_src == TRIG_FOLLOW &&
                   cmd->convert_src == TRIG_TIMER) {
+               devpriv->ai_ctrl_mode = ME4000_AI_CTRL_MODE_0;
        } else if (cmd->start_src == TRIG_EXT &&
                   cmd->scan_begin_src == TRIG_TIMER &&
                   cmd->convert_src == TRIG_TIMER) {
+               devpriv->ai_ctrl_mode = ME4000_AI_CTRL_MODE_1;
        } else if (cmd->start_src == TRIG_EXT &&
                   cmd->scan_begin_src == TRIG_FOLLOW &&
                   cmd->convert_src == TRIG_TIMER) {
+               devpriv->ai_ctrl_mode = ME4000_AI_CTRL_MODE_1;
        } else if (cmd->start_src == TRIG_EXT &&
                   cmd->scan_begin_src == TRIG_EXT &&
                   cmd->convert_src == TRIG_TIMER) {
+               devpriv->ai_ctrl_mode = ME4000_AI_CTRL_MODE_2;
        } else if (cmd->start_src == TRIG_EXT &&
                   cmd->scan_begin_src == TRIG_EXT &&
                   cmd->convert_src == TRIG_EXT) {
+               devpriv->ai_ctrl_mode = ME4000_AI_CTRL_MODE_0 |
+                                       ME4000_AI_CTRL_MODE_1;
        } else {
                err |= -EINVAL;
        }