[PATCH 27/74] staging: comedi: fix minimum AO period for NI 625x and NI 628x
From: Herton Ronaldo Krzesinski <hidden>
Date: 2013-01-24 03:42:10
Also in:
lkml
Subsystem:
staging subsystem, the rest · Maintainers:
Greg Kroah-Hartman, Linus Torvalds
3.5.7.4 -stable review patch. If anyone has any objections, please let me know. ------------------ From: =?UTF-8?q?=C3=89ric=20Piel?= <redacted> commit 34b55d8c48f4f76044d8f4d6ec3dc786cf210312 upstream. 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 <redacted> Acked-By: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Herton Ronaldo Krzesinski <redacted> --- drivers/staging/comedi/drivers/ni_pcimio.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/drivers/staging/comedi/drivers/ni_pcimio.c b/drivers/staging/comedi/drivers/ni_pcimio.c
index 3974c0d..fa09fd7 100644
--- a/drivers/staging/comedi/drivers/ni_pcimio.c
+++ b/drivers/staging/comedi/drivers/ni_pcimio.c@@ -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,
--
1.7.9.5