This is a note to let you know that I've just added the patch titled

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

to the 3.7-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     staging-comedi-fix-minimum-ao-period-for-ni-625x-and-ni-628x.patch
and it can be found in the queue-3.7 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 34b55d8c48f4f76044d8f4d6ec3dc786cf210312 Mon Sep 17 00:00:00 2001
From: Éric Piel <[email protected]>
Date: Wed, 19 Dec 2012 13:03:13 +0100
Subject: staging: comedi: fix minimum AO period for NI 625x and NI 628x

From: Éric Piel <[email protected]>

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 <[email protected]>
Acked-By: Ian Abbott <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 drivers/staging/comedi/drivers/ni_pcimio.c |   16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

--- 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_b
         .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_b
         .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_b
         .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_b
         .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_b
         .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_b
         .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_b
         .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_b
         .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,


Patches currently in stable-queue which might be from [email protected] are

queue-3.7/staging-comedi-comedi_test-fix-race-when-cancelling-command.patch
queue-3.7/staging-comedi-fix-minimum-ao-period-for-ni-625x-and-ni-628x.patch
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