UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

staging: comedi: fix minimum AO period for NI 625x and NI 628x 

The minimum period was set to 357 ns, while the divider for these boards is 50
ns. This prevented to output at maximum speed as ni_ao_cmdtest() would return
357 but would not accept it.

Not sure why it was set to 357 ns (this was done before the git history,
which starts 5 years ago). My guess is that it comes from reading the
specification stating a 2.8 MHz rate (~ 357 ns). The latest
specification states a 2.86 MHz rate (~ 350 ns), which makes a lot
more sense.

Tested on a pci-6251.

Signed-off-by: Éric Piel <piel@delmic.com>
Acked-By: Ian Abbott <abbotti@mev.co.uk>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Éric Piel 2012-12-19 13:03:13 +01:00 committed by Greg Kroah-Hartman
parent 9349f8af28
commit 34b55d8c48
1 changed files with 8 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
drivers/staging/comedi/drivers/ni_pcimio.c
View File

@ -963,7 +963,7 @@ static const struct ni_board_struct ni_boards[] = {
.ao_range_table = &range_ni_M_625x_ao,
.reg_type = ni_reg_625x,
.ao_unipolar = 0,
.ao_speed = 357,
.ao_speed = 350,
.num_p0_dio_channels = 8,
.caldac = {caldac_none},
.has_8255 = 0,
@ -982,7 +982,7 @@ static const struct ni_board_struct ni_boards[] = {
.ao_range_table = &range_ni_M_625x_ao,
.reg_type = ni_reg_625x,
.ao_unipolar = 0,
.ao_speed = 357,
.ao_speed = 350,
.num_p0_dio_channels = 8,
.caldac = {caldac_none},
.has_8255 = 0,
@ -1001,7 +1001,7 @@ static const struct ni_board_struct ni_boards[] = {
.ao_range_table = &range_ni_M_625x_ao,
.reg_type = ni_reg_625x,
.ao_unipolar = 0,
.ao_speed = 357,
.ao_speed = 350,
.num_p0_dio_channels = 8,
.caldac = {caldac_none},
.has_8255 = 0,
@ -1037,7 +1037,7 @@ static const struct ni_board_struct ni_boards[] = {
.ao_range_table = &range_ni_M_625x_ao,
.reg_type = ni_reg_625x,
.ao_unipolar = 0,
.ao_speed = 357,
.ao_speed = 350,
.num_p0_dio_channels = 32,
.caldac = {caldac_none},
.has_8255 = 0,
@ -1056,7 +1056,7 @@ static const struct ni_board_struct ni_boards[] = {
.ao_range_table = &range_ni_M_625x_ao,
.reg_type = ni_reg_625x,
.ao_unipolar = 0,
.ao_speed = 357,
.ao_speed = 350,
.num_p0_dio_channels = 32,
.caldac = {caldac_none},
.has_8255 = 0,
@ -1092,7 +1092,7 @@ static const struct ni_board_struct ni_boards[] = {
.ao_range_table = &range_ni_M_628x_ao,
.reg_type = ni_reg_628x,
.ao_unipolar = 1,
.ao_speed = 357,
.ao_speed = 350,
.num_p0_dio_channels = 8,
.caldac = {caldac_none},
.has_8255 = 0,
@ -1111,7 +1111,7 @@ static const struct ni_board_struct ni_boards[] = {
.ao_range_table = &range_ni_M_628x_ao,
.reg_type = ni_reg_628x,
.ao_unipolar = 1,
.ao_speed = 357,
.ao_speed = 350,
.num_p0_dio_channels = 8,
.caldac = {caldac_none},
.has_8255 = 0,
@ -1147,7 +1147,7 @@ static const struct ni_board_struct ni_boards[] = {
.ao_range_table = &range_ni_M_628x_ao,
.reg_type = ni_reg_628x,
.ao_unipolar = 1,
.ao_speed = 357,
.ao_speed = 350,
.num_p0_dio_channels = 32,
.caldac = {caldac_none},
.has_8255 = 0,