staging: comedi: ni_tio: tidy up ni_tio_set_sync_mode()

The 'force_alt_sync' paramater is always 0. Remove it.

Absorb the GI_ALT_SYNC() inline helper and use some local variables
to clarify this function.

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 ce64cc3..2c33b28 100644 (file)
--- a/drivers/staging/comedi/drivers/ni_tio.c
+++ b/drivers/staging/comedi/drivers/ni_tio.c
@@ -111,19 +111,6 @@
 #define NI_660X_LOGIC_LOW_GATE2_SEL    0x1f
 #define NI_660X_MAX_UP_DOWN_PIN                7
 
-static inline unsigned int GI_ALT_SYNC(enum ni_gpct_variant variant)
-{
-       switch (variant) {
-       case ni_gpct_variant_e_series:
-       default:
-               return 0;
-       case ni_gpct_variant_m_series:
-               return GI_M_ALT_SYNC;
-       case ni_gpct_variant_660x:
-               return GI_660X_ALT_SYNC;
-       }
-}
-
 static inline unsigned int GI_PRESCALE_X2(enum ni_gpct_variant variant)
 {
        switch (variant) {
@@ -465,48 +452,56 @@ ni_tio_generic_clock_src_select(const struct ni_gpct *counter)
        }
 }
 
-static void ni_tio_set_sync_mode(struct ni_gpct *counter, int force_alt_sync)
+static void ni_tio_set_sync_mode(struct ni_gpct *counter)
 {
        struct ni_gpct_device *counter_dev = counter->counter_dev;
        unsigned int cidx = counter->counter_index;
-       unsigned int counting_mode_reg = NITIO_CNT_MODE_REG(cidx);
        static const u64 min_normal_sync_period_ps = 25000;
+       unsigned int mask = 0;
+       unsigned int bits = 0;
+       unsigned int reg;
        unsigned int mode;
-       u64 clock_period_ps;
+       u64 ps;
+       bool force_alt_sync;
 
-       if (!ni_tio_counting_mode_registers_present(counter_dev))
+       /* only m series and 660x variants have counting mode registers */
+       switch (counter_dev->variant) {
+       case ni_gpct_variant_e_series:
+       default:
                return;
+       case ni_gpct_variant_m_series:
+               mask = GI_M_ALT_SYNC;
+               break;
+       case ni_gpct_variant_660x:
+               mask = GI_660X_ALT_SYNC;
+               break;
+       }
 
-       mode = ni_tio_get_soft_copy(counter, counting_mode_reg);
+       reg = NITIO_CNT_MODE_REG(cidx);
+       mode = ni_tio_get_soft_copy(counter, reg);
        switch (mode & GI_CNT_MODE_MASK) {
        case GI_CNT_MODE_QUADX1:
        case GI_CNT_MODE_QUADX2:
        case GI_CNT_MODE_QUADX4:
        case GI_CNT_MODE_SYNC_SRC:
-               force_alt_sync = 1;
+               force_alt_sync = true;
                break;
        default:
+               force_alt_sync = false;
                break;
        }
 
-       clock_period_ps = ni_tio_clock_period_ps(counter,
-                               ni_tio_generic_clock_src_select(counter));
+       ps = ni_tio_clock_period_ps(counter,
+                                   ni_tio_generic_clock_src_select(counter));
 
        /*
         * It's not clear what we should do if clock_period is unknown, so we
-        * are not using the alt sync bit in that case, but allow the caller
-        * to decide by using the force_alt_sync parameter.
+        * are not using the alt sync bit in that case.
         */
-       if (force_alt_sync ||
-           (clock_period_ps && clock_period_ps < min_normal_sync_period_ps)) {
-               ni_tio_set_bits(counter, counting_mode_reg,
-                               GI_ALT_SYNC(counter_dev->variant),
-                               GI_ALT_SYNC(counter_dev->variant));
-       } else {
-               ni_tio_set_bits(counter, counting_mode_reg,
-                               GI_ALT_SYNC(counter_dev->variant),
-                               0x0);
-       }
+       if (force_alt_sync || (ps && ps < min_normal_sync_period_ps))
+               bits = mask;
+
+       ni_tio_set_bits(counter, reg, mask, bits);
 }
 
 static int ni_tio_set_counter_mode(struct ni_gpct *counter, unsigned int mode)
@@ -552,7 +547,7 @@ static int ni_tio_set_counter_mode(struct ni_gpct *counter, unsigned int mode)
                ni_tio_set_bits(counter, NITIO_CNT_MODE_REG(cidx),
                                GI_CNT_MODE_MASK | GI_INDEX_PHASE_MASK |
                                GI_INDEX_MODE, bits);
-               ni_tio_set_sync_mode(counter, 0);
+               ni_tio_set_sync_mode(counter);
        }
 
        ni_tio_set_bits(counter, NITIO_CMD_REG(cidx), GI_CNT_DIR_MASK,
@@ -807,7 +802,7 @@ static int ni_tio_set_clock_src(struct ni_gpct *counter,
                                GI_PRESCALE_X8(counter_dev->variant), bits);
        }
        counter->clock_period_ps = period_ns * 1000;
-       ni_tio_set_sync_mode(counter, 0);
+       ni_tio_set_sync_mode(counter);
        return 0;
 }