diff options
| author | H Hartley Sweeten <hsweeten@visionengravers.com> | 2015-08-05 10:44:51 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-08-07 15:03:28 -0700 |
| commit | 245bd462440ca5914286c71051fdc5af506e76cb (patch) | |
| tree | 7a75fc5f72117ef356a82b4ae8bc1c5a0dbc6f3c /drivers/staging/comedi/drivers/me4000.c | |
| parent | 271f5aa04be0ff3d0c6fc8ccc31a6b0d3294461b (diff) | |
staging: comedi: me4000: simplify analog input range programming
The comedi_lrange table for the analog inputs is inverted compared
to the values that need to be written to the ME4000_AI_CHANNEL_LIST_REG
to select the range.
Create a macro, ME4000_AI_LIST_RANGE(), to handle the inversion. Remove
the old defines and simplify the code a bit.
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>
Diffstat (limited to 'drivers/staging/comedi/drivers/me4000.c')
| -rw-r--r-- | drivers/staging/comedi/drivers/me4000.c | 41 |
1 files changed, 9 insertions, 32 deletions
diff --git a/drivers/staging/comedi/drivers/me4000.c b/drivers/staging/comedi/drivers/me4000.c index ba3313c069d0..1001d6379480 100644 --- a/drivers/staging/comedi/drivers/me4000.c +++ b/drivers/staging/comedi/drivers/me4000.c @@ -111,10 +111,7 @@ broken. #define ME4000_AI_CTRL_BIT_EX_TRIG_BOTH (1 << 31) #define ME4000_AI_CHANNEL_LIST_REG 0x78 #define ME4000_AI_LIST_INPUT_DIFFERENTIAL (1 << 5) -#define ME4000_AI_LIST_RANGE_BIPOLAR_10 (0 << 6) -#define ME4000_AI_LIST_RANGE_BIPOLAR_2_5 (1 << 6) -#define ME4000_AI_LIST_RANGE_UNIPOLAR_10 (2 << 6) -#define ME4000_AI_LIST_RANGE_UNIPOLAR_2_5 (3 << 6) +#define ME4000_AI_LIST_RANGE(x) ((3 - ((x) & 3)) << 6) #define ME4000_AI_LIST_LAST_ENTRY (1 << 8) #define ME4000_AI_DATA_REG 0x7c #define ME4000_AI_CHAN_TIMER_REG 0x80 @@ -301,6 +298,12 @@ static const struct me4000_board me4000_boards[] = { }, }; +/* + * NOTE: the ranges here are inverted compared to the values + * written to the ME4000_AI_CHANNEL_LIST_REG, + * + * The ME4000_AI_LIST_RANGE() macro handles the inversion. + */ static const struct comedi_lrange me4000_ai_range = { 4, { UNI_RANGE(2.5), @@ -455,24 +458,7 @@ static int me4000_ai_insn_read(struct comedi_device *dev, return -EINVAL; } - switch (rang) { - case 0: - entry |= ME4000_AI_LIST_RANGE_UNIPOLAR_2_5; - break; - case 1: - entry |= ME4000_AI_LIST_RANGE_UNIPOLAR_10; - break; - case 2: - entry |= ME4000_AI_LIST_RANGE_BIPOLAR_2_5; - break; - case 3: - entry |= ME4000_AI_LIST_RANGE_BIPOLAR_10; - break; - default: - dev_err(dev->class_dev, "Invalid range specified\n"); - return -EINVAL; - } - + entry |= ME4000_AI_LIST_RANGE(rang); entry |= chan; if (aref == AREF_DIFF) { if (!(s->subdev_flags && SDF_DIFF)) { @@ -680,16 +666,7 @@ static int ai_write_chanlist(struct comedi_device *dev, rang = CR_RANGE(cmd->chanlist[i]); aref = CR_AREF(cmd->chanlist[i]); - entry = chan; - - if (rang == 0) - entry |= ME4000_AI_LIST_RANGE_UNIPOLAR_2_5; - else if (rang == 1) - entry |= ME4000_AI_LIST_RANGE_UNIPOLAR_10; - else if (rang == 2) - entry |= ME4000_AI_LIST_RANGE_BIPOLAR_2_5; - else - entry |= ME4000_AI_LIST_RANGE_BIPOLAR_10; + entry = chan | ME4000_AI_LIST_RANGE(rang); if (aref == AREF_DIFF) entry |= ME4000_AI_LIST_INPUT_DIFFERENTIAL; |