staging: comedi: ni_mio_common: clarify the cmd->start_arg validation and use

Clarify the cmd->start_arg validation in Step 3 of the (*do_cmdtest)
functions.

For a TRIG_INT source, the cmd->start_arg is actually the valid
trig_num that is used by the async (*inttrig) callbacks.

Refactor the (*inttrig) functions so that the cmd->start_arg is used
to check the trig_num instead of the open coded values.

For aesthetics, refactor the (*do_cmd) functions to use if/else instead
of the switch to handle the cmd->start_src.

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/ni_mio_common.c b/drivers/staging/comedi/drivers/ni_mio_common.c
index 2e26622edee5e9eb66461db7d7e335140199b48a..087b533625df72af99634af14ac606b4c3e74170 100644 (file)
--- a/drivers/staging/comedi/drivers/ni_mio_common.c
+++ b/drivers/staging/comedi/drivers/ni_mio_common.c
@@ -2080,7 +2080,7 @@ static int ni_ai_cmdtest(struct comedi_device *dev, struct comedi_subdevice *s,
        const struct ni_board_struct *board = comedi_board(dev);
        struct ni_private *devpriv = dev->private;
        int err = 0;
-       int tmp;
+       unsigned int tmp;
        unsigned int sources;
 
        /* Step 1 : check if triggers are trivially valid */
@@ -2119,17 +2119,19 @@ static int ni_ai_cmdtest(struct comedi_device *dev, struct comedi_subdevice *s,
 
        /* Step 3: check if arguments are trivially valid */
 
-       if (cmd->start_src == TRIG_EXT) {
-               /* external trigger */
-               unsigned int tmp = CR_CHAN(cmd->start_arg);
+       switch (cmd->start_src) {
+       case TRIG_NOW:
+       case TRIG_INT:
+               err |= cfc_check_trigger_arg_is(&cmd->start_arg, 0);
+               break;
+       case TRIG_EXT:
+               tmp = CR_CHAN(cmd->start_arg);
 
                if (tmp > 16)
                        tmp = 16;
                tmp |= (cmd->start_arg & (CR_INVERT | CR_EDGE));
                err |= cfc_check_trigger_arg_is(&cmd->start_arg, tmp);
-       } else {
-               /* true for both TRIG_NOW and TRIG_INT */
-               err |= cfc_check_trigger_arg_is(&cmd->start_arg, 0);
+               break;
        }
 
        if (cmd->scan_begin_src == TRIG_TIMER) {
@@ -2510,30 +2512,28 @@ static int ni_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
        }
 #endif
 
-       switch (cmd->start_src) {
-       case TRIG_NOW:
+       if (cmd->start_src == TRIG_NOW) {
                /* AI_START1_Pulse */
                devpriv->stc_writew(dev, AI_START1_Pulse | devpriv->ai_cmd2,
                                    AI_Command_2_Register);
                s->async->inttrig = NULL;
-               break;
-       case TRIG_EXT:
+       } else if (cmd->start_src == TRIG_EXT) {
                s->async->inttrig = NULL;
-               break;
-       case TRIG_INT:
-               s->async->inttrig = &ni_ai_inttrig;
-               break;
+       } else {        /* TRIG_INT */
+               s->async->inttrig = ni_ai_inttrig;
        }
 
        return 0;
 }
 
-static int ni_ai_inttrig(struct comedi_device *dev, struct comedi_subdevice *s,
-                        unsigned int trignum)
+static int ni_ai_inttrig(struct comedi_device *dev,
+                        struct comedi_subdevice *s,
+                        unsigned int trig_num)
 {
        struct ni_private *devpriv = dev->private;
+       struct comedi_cmd *cmd = &s->async->cmd;
 
-       if (trignum != 0)
+       if (trig_num != cmd->start_arg)
                return -EINVAL;
 
        devpriv->stc_writew(dev, AI_START1_Pulse | devpriv->ai_cmd2,
@@ -2946,17 +2946,19 @@ static int ni_ao_insn_config(struct comedi_device *dev,
        return -EINVAL;
 }
 
-static int ni_ao_inttrig(struct comedi_device *dev, struct comedi_subdevice *s,
-                        unsigned int trignum)
+static int ni_ao_inttrig(struct comedi_device *dev,
+                        struct comedi_subdevice *s,
+                        unsigned int trig_num)
 {
        const struct ni_board_struct *board __maybe_unused = comedi_board(dev);
        struct ni_private *devpriv = dev->private;
+       struct comedi_cmd *cmd = &s->async->cmd;
        int ret;
        int interrupt_b_bits;
        int i;
        static const int timeout = 1000;
 
-       if (trignum != 0)
+       if (trig_num != cmd->start_arg)
                return -EINVAL;
 
        /* Null trig at beginning prevent ao start trigger from executing more than
@@ -3217,7 +3219,7 @@ static int ni_ao_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
                            AO_BC_TC_Interrupt_Enable, 1);
        }
 
-       s->async->inttrig = &ni_ao_inttrig;
+       s->async->inttrig = ni_ao_inttrig;
 
        return 0;
 }
@@ -3228,7 +3230,7 @@ static int ni_ao_cmdtest(struct comedi_device *dev, struct comedi_subdevice *s,
        const struct ni_board_struct *board = comedi_board(dev);
        struct ni_private *devpriv = dev->private;
        int err = 0;
-       int tmp;
+       unsigned int tmp;
 
        /* Step 1 : check if triggers are trivially valid */
 
@@ -3258,17 +3260,18 @@ static int ni_ao_cmdtest(struct comedi_device *dev, struct comedi_subdevice *s,
 
        /* Step 3: check if arguments are trivially valid */
 
-       if (cmd->start_src == TRIG_EXT) {
-               /* external trigger */
-               unsigned int tmp = CR_CHAN(cmd->start_arg);
+       switch (cmd->start_src) {
+       case TRIG_INT:
+               err |= cfc_check_trigger_arg_is(&cmd->start_arg, 0);
+               break;
+       case TRIG_EXT:
+               tmp = CR_CHAN(cmd->start_arg);
 
                if (tmp > 18)
                        tmp = 18;
                tmp |= (cmd->start_arg & (CR_INVERT | CR_EDGE));
                err |= cfc_check_trigger_arg_is(&cmd->start_arg, tmp);
-       } else {
-               /* true for both TRIG_NOW and TRIG_INT */
-               err |= cfc_check_trigger_arg_is(&cmd->start_arg, 0);
+               break;
        }
 
        if (cmd->scan_begin_src == TRIG_TIMER) {
@@ -3537,21 +3540,28 @@ static int ni_cdio_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
        retval = ni_request_cdo_mite_channel(dev);
        if (retval < 0)
                return retval;
-       s->async->inttrig = &ni_cdo_inttrig;
+
+       s->async->inttrig = ni_cdo_inttrig;
+
        return 0;
 }
 
-static int ni_cdo_inttrig(struct comedi_device *dev, struct comedi_subdevice *s,
-                         unsigned int trignum)
+static int ni_cdo_inttrig(struct comedi_device *dev,
+                         struct comedi_subdevice *s,
+                         unsigned int trig_num)
 {
 #ifdef PCIDMA
        struct ni_private *devpriv = dev->private;
        unsigned long flags;
 #endif
+       struct comedi_cmd *cmd = &s->async->cmd;
        int retval = 0;
        unsigned i;
        const unsigned timeout = 1000;
 
+       if (trig_num != cmd->start_arg)
+               return -EINVAL;
+
        s->async->inttrig = NULL;
 
        /* read alloc the entire buffer */