staging: comedi: ni_tio: remove BUG() checks for ni_tio_get_gate_src()

This function calls some helper functions to convert the counter variant
specific gate select bits into the generic enum ni_gpct_clock_source_bits
equivelent. These helper functions currently BUG() if the gate select
bits are invalid.

This should never happen but refactor the code to return -EINVAL instead
and remove the BUG() checks.

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_tio.c b/drivers/staging/comedi/drivers/ni_tio.c
index 564ec9b..51dd368 100644 (file)
--- a/drivers/staging/comedi/drivers/ni_tio.c
+++ b/drivers/staging/comedi/drivers/ni_tio.c
@@ -1065,114 +1065,157 @@ static int ni_tio_set_other_src(struct ni_gpct *counter, unsigned int index,
        return 0;
 }
 
-static unsigned int ni_660x_gate_to_generic_gate(unsigned int gate)
+static int ni_660x_gate_to_generic_gate(unsigned int gate, unsigned int *src)
 {
+       unsigned int source;
        unsigned int i;
 
        switch (gate) {
        case NI_660X_SRC_PIN_I_GATE_SEL:
-               return NI_GPCT_SOURCE_PIN_i_GATE_SELECT;
+               source = NI_GPCT_SOURCE_PIN_i_GATE_SELECT;
+               break;
        case NI_660X_GATE_PIN_I_GATE_SEL:
-               return NI_GPCT_GATE_PIN_i_GATE_SELECT;
+               source = NI_GPCT_GATE_PIN_i_GATE_SELECT;
+               break;
        case NI_660X_NEXT_SRC_GATE_SEL:
-               return NI_GPCT_NEXT_SOURCE_GATE_SELECT;
+               source = NI_GPCT_NEXT_SOURCE_GATE_SELECT;
+               break;
        case NI_660X_NEXT_OUT_GATE_SEL:
-               return NI_GPCT_NEXT_OUT_GATE_SELECT;
+               source = NI_GPCT_NEXT_OUT_GATE_SELECT;
+               break;
        case NI_660X_LOGIC_LOW_GATE_SEL:
-               return NI_GPCT_LOGIC_LOW_GATE_SELECT;
+               source = NI_GPCT_LOGIC_LOW_GATE_SELECT;
+               break;
        default:
                for (i = 0; i <= NI_660X_MAX_RTSI_CHAN; ++i) {
-                       if (gate == NI_660X_RTSI_GATE_SEL(i))
-                               return NI_GPCT_RTSI_GATE_SELECT(i);
+                       if (gate == NI_660X_RTSI_GATE_SEL(i)) {
+                               source = NI_GPCT_RTSI_GATE_SELECT(i);
+                               break;
+                       }
                }
+               if (i <= NI_660X_MAX_RTSI_CHAN)
+                       break;
                for (i = 0; i <= NI_660X_MAX_GATE_PIN; ++i) {
-                       if (gate == NI_660X_PIN_GATE_SEL(i))
-                               return NI_GPCT_GATE_PIN_GATE_SELECT(i);
+                       if (gate == NI_660X_PIN_GATE_SEL(i)) {
+                               source = NI_GPCT_GATE_PIN_GATE_SELECT(i);
+                               break;
+                       }
                }
-               BUG();
-               break;
+               if (i <= NI_660X_MAX_GATE_PIN)
+                       break;
+               return -EINVAL;
        }
+       *src = source;
        return 0;
 };
 
-static unsigned int ni_m_gate_to_generic_gate(unsigned int gate)
+static int ni_m_gate_to_generic_gate(unsigned int gate, unsigned int *src)
 {
+       unsigned int source;
        unsigned int i;
 
        switch (gate) {
        case NI_M_TIMESTAMP_MUX_GATE_SEL:
-               return NI_GPCT_TIMESTAMP_MUX_GATE_SELECT;
+               source = NI_GPCT_TIMESTAMP_MUX_GATE_SELECT;
+               break;
        case NI_M_AI_START2_GATE_SEL:
-               return NI_GPCT_AI_START2_GATE_SELECT;
+               source = NI_GPCT_AI_START2_GATE_SELECT;
+               break;
        case NI_M_PXI_STAR_TRIGGER_GATE_SEL:
-               return NI_GPCT_PXI_STAR_TRIGGER_GATE_SELECT;
+               source = NI_GPCT_PXI_STAR_TRIGGER_GATE_SELECT;
+               break;
        case NI_M_NEXT_OUT_GATE_SEL:
-               return NI_GPCT_NEXT_OUT_GATE_SELECT;
+               source = NI_GPCT_NEXT_OUT_GATE_SELECT;
+               break;
        case NI_M_AI_START1_GATE_SEL:
-               return NI_GPCT_AI_START1_GATE_SELECT;
+               source = NI_GPCT_AI_START1_GATE_SELECT;
+               break;
        case NI_M_NEXT_SRC_GATE_SEL:
-               return NI_GPCT_NEXT_SOURCE_GATE_SELECT;
+               source = NI_GPCT_NEXT_SOURCE_GATE_SELECT;
+               break;
        case NI_M_ANALOG_TRIG_OUT_GATE_SEL:
-               return NI_GPCT_ANALOG_TRIGGER_OUT_GATE_SELECT;
+               source = NI_GPCT_ANALOG_TRIGGER_OUT_GATE_SELECT;
+               break;
        case NI_M_LOGIC_LOW_GATE_SEL:
-               return NI_GPCT_LOGIC_LOW_GATE_SELECT;
+               source = NI_GPCT_LOGIC_LOW_GATE_SELECT;
+               break;
        default:
                for (i = 0; i <= NI_M_MAX_RTSI_CHAN; ++i) {
-                       if (gate == NI_M_RTSI_GATE_SEL(i))
-                               return NI_GPCT_RTSI_GATE_SELECT(i);
+                       if (gate == NI_M_RTSI_GATE_SEL(i)) {
+                               source = NI_GPCT_RTSI_GATE_SELECT(i);
+                               break;
+                       }
                }
+               if (i <= NI_M_MAX_RTSI_CHAN)
+                       break;
                for (i = 0; i <= NI_M_MAX_PFI_CHAN; ++i) {
-                       if (gate == NI_M_PFI_GATE_SEL(i))
-                               return NI_GPCT_PFI_GATE_SELECT(i);
+                       if (gate == NI_M_PFI_GATE_SEL(i)) {
+                               source = NI_GPCT_PFI_GATE_SELECT(i);
+                               break;
+                       }
                }
-               BUG();
-               break;
+               if (i <= NI_M_MAX_PFI_CHAN)
+                       break;
+               return -EINVAL;
        }
+       *src = source;
        return 0;
 };
 
-static unsigned int ni_660x_gate2_to_generic_gate(unsigned int gate)
+static int ni_660x_gate2_to_generic_gate(unsigned int gate, unsigned int *src)
 {
+       unsigned int source;
        unsigned int i;
 
        switch (gate) {
        case NI_660X_SRC_PIN_I_GATE2_SEL:
-               return NI_GPCT_SOURCE_PIN_i_GATE_SELECT;
+               source = NI_GPCT_SOURCE_PIN_i_GATE_SELECT;
+               break;
        case NI_660X_UD_PIN_I_GATE2_SEL:
-               return NI_GPCT_UP_DOWN_PIN_i_GATE_SELECT;
+               source = NI_GPCT_UP_DOWN_PIN_i_GATE_SELECT;
+               break;
        case NI_660X_NEXT_SRC_GATE2_SEL:
-               return NI_GPCT_NEXT_SOURCE_GATE_SELECT;
+               source = NI_GPCT_NEXT_SOURCE_GATE_SELECT;
+               break;
        case NI_660X_NEXT_OUT_GATE2_SEL:
-               return NI_GPCT_NEXT_OUT_GATE_SELECT;
+               source = NI_GPCT_NEXT_OUT_GATE_SELECT;
+               break;
        case NI_660X_SELECTED_GATE2_SEL:
-               return NI_GPCT_SELECTED_GATE_GATE_SELECT;
+               source = NI_GPCT_SELECTED_GATE_GATE_SELECT;
+               break;
        case NI_660X_LOGIC_LOW_GATE2_SEL:
-               return NI_GPCT_LOGIC_LOW_GATE_SELECT;
+               source = NI_GPCT_LOGIC_LOW_GATE_SELECT;
+               break;
        default:
                for (i = 0; i <= NI_660X_MAX_RTSI_CHAN; ++i) {
-                       if (gate == NI_660X_RTSI_GATE2_SEL(i))
-                               return NI_GPCT_RTSI_GATE_SELECT(i);
+                       if (gate == NI_660X_RTSI_GATE2_SEL(i)) {
+                               source = NI_GPCT_RTSI_GATE_SELECT(i);
+                               break;
+                       }
                }
+               if (i <= NI_660X_MAX_RTSI_CHAN)
+                       break;
                for (i = 0; i <= NI_660X_MAX_UP_DOWN_PIN; ++i) {
-                       if (gate == NI_660X_UD_PIN_GATE2_SEL(i))
-                               return NI_GPCT_UP_DOWN_PIN_GATE_SELECT(i);
+                       if (gate == NI_660X_UD_PIN_GATE2_SEL(i)) {
+                               source = NI_GPCT_UP_DOWN_PIN_GATE_SELECT(i);
+                               break;
+                       }
                }
-               BUG();
-               break;
+               if (i <= NI_660X_MAX_UP_DOWN_PIN)
+                       break;
+               return -EINVAL;
        }
+       *src = source;
        return 0;
 };
 
-static unsigned int ni_m_gate2_to_generic_gate(unsigned int gate)
+static int ni_m_gate2_to_generic_gate(unsigned int gate, unsigned int *src)
 {
        /*
         * FIXME: the second gate sources for the m series are undocumented,
         * so we just return the raw bits for now.
         */
-       switch (gate) {
-       default:
-               return gate;
-       }
+       *src = gate;
        return 0;
 };
 
@@ -1184,6 +1227,7 @@ static int ni_tio_get_gate_src(struct ni_gpct *counter, unsigned int gate_index,
        unsigned int mode;
        unsigned int reg;
        unsigned int gate;
+       int ret;
 
        mode = ni_tio_get_soft_copy(counter, NITIO_MODE_REG(cidx));
        if (((mode & GI_GATING_MODE_MASK) == GI_GATING_DISABLED) ||
@@ -1202,12 +1246,14 @@ static int ni_tio_get_gate_src(struct ni_gpct *counter, unsigned int gate_index,
                case ni_gpct_variant_e_series:
                case ni_gpct_variant_m_series:
                default:
-                       *gate_source = ni_m_gate_to_generic_gate(gate);
+                       ret = ni_m_gate_to_generic_gate(gate, gate_source);
                        break;
                case ni_gpct_variant_660x:
-                       *gate_source = ni_660x_gate_to_generic_gate(gate);
+                       ret = ni_660x_gate_to_generic_gate(gate, gate_source);
                        break;
                }
+               if (ret)
+                       return ret;
                if (mode & GI_GATE_POL_INVERT)
                        *gate_source |= CR_INVERT;
                if ((mode & GI_GATING_MODE_MASK) != GI_LEVEL_GATING)
@@ -1221,12 +1267,14 @@ static int ni_tio_get_gate_src(struct ni_gpct *counter, unsigned int gate_index,
                case ni_gpct_variant_e_series:
                case ni_gpct_variant_m_series:
                default:
-                       *gate_source = ni_m_gate2_to_generic_gate(gate);
+                       ret = ni_m_gate2_to_generic_gate(gate, gate_source);
                        break;
                case ni_gpct_variant_660x:
-                       *gate_source = ni_660x_gate2_to_generic_gate(gate);
+                       ret = ni_660x_gate2_to_generic_gate(gate, gate_source);
                        break;
                }
+               if (ret)
+                       return ret;
                if (counter_dev->regs[reg] & GI_GATE2_POL_INVERT)
                        *gate_source |= CR_INVERT;
                /* second gate can't have edge/level mode set independently */