[PATCH - v2] LEDS: tca6507 - fix up some comments.

2013-11-12 Thread NeilBrown

In particular fix the capitalisation of GPIO and LED and
correct TCA6507_MAKE_CPIO, but also rewrite the comment about
platform-data to include reference to devicetree.

Also re-wrap comments to fit 80 columns.

Reported-by: Bryan Wu 
Signed-off-by: NeilBrown 

diff --git a/drivers/leds/leds-tca6507.c b/drivers/leds/leds-tca6507.c
index 93a2b1759054..503df834c690 100644
--- a/drivers/leds/leds-tca6507.c
+++ b/drivers/leds/leds-tca6507.c
@@ -4,77 +4,87 @@
  * The TCA6507 is a programmable LED controller that can drive 7
  * separate lines either by holding them low, or by pulsing them
  * with modulated width.
- * The modulation can be varied in a simple pattern to produce a blink or
- * double-blink.
+ * The modulation can be varied in a simple pattern to produce a
+ * blink or double-blink.
  *
- * This driver can configure each line either as a 'GPIO' which is out-only
- * (no pull-up) or as an LED with variable brightness and hardware-assisted
- * blinking.
+ * This driver can configure each line either as a 'GPIO' which is
+ * out-only (pull-up resistor required) or as an LED with variable
+ * brightness and hardware-assisted blinking.
  *
- * Apart from OFF and ON there are three programmable brightness levels which
- * can be programmed from 0 to 15 and indicate how many 500usec intervals in
- * each 8msec that the led is 'on'.  The levels are named MASTER, BANK0 and
- * BANK1.
+ * Apart from OFF and ON there are three programmable brightness
+ * levels which can be programmed from 0 to 15 and indicate how many
+ * 500usec intervals in each 8msec that the led is 'on'.  The levels
+ * are named MASTER, BANK0 and BANK1.
  *
- * There are two different blink rates that can be programmed, each with
- * separate time for rise, on, fall, off and second-off.  Thus if 3 or more
- * different non-trivial rates are required, software must be used for the 
extra
- * rates. The two different blink rates must align with the two levels BANK0 
and
- * BANK1.
- * This driver does not support double-blink so 'second-off' always matches
- * 'off'.
+ * There are two different blink rates that can be programmed, each
+ * with separate time for rise, on, fall, off and second-off.  Thus if
+ * 3 or more different non-trivial rates are required, software must
+ * be used for the extra rates. The two different blink rates must
+ * align with the two levels BANK0 and BANK1.  This driver does not
+ * support double-blink so 'second-off' always matches 'off'.
  *
- * Only 16 different times can be programmed in a roughly logarithmic scale 
from
- * 64ms to 16320ms.  To be precise the possible times are:
+ * Only 16 different times can be programmed in a roughly logarithmic
+ * scale from 64ms to 16320ms.  To be precise the possible times are:
  *0, 64, 128, 192, 256, 384, 512, 768,
  *1024, 1536, 2048, 3072, 4096, 5760, 8128, 16320
  *
- * Times that cannot be closely matched with these must be
- * handled in software.  This driver allows 12.5% error in matching.
+ * Times that cannot be closely matched with these must be handled in
+ * software.  This driver allows 12.5% error in matching.
  *
- * This driver does not allow rise/fall rates to be set explicitly.  When 
trying
- * to match a given 'on' or 'off' period, an appropriate pair of 'change' and
- * 'hold' times are chosen to get a close match.  If the target delay is even,
- * the 'change' number will be the smaller; if odd, the 'hold' number will be
- * the smaller.
-
- * Choosing pairs of delays with 12.5% errors allows us to match delays in the
- * ranges: 56-72, 112-144, 168-216, 224-27504, 28560-36720.
- * 26% of the achievable sums can be matched by multiple pairings. For example
- * 1536 == 1536+0, 1024+512, or 768+768.  This driver will always choose the
- * pairing with the least maximum - 768+768 in this case.  Other pairings are
- * not available.
+ * This driver does not allow rise/fall rates to be set explicitly.
+ * When trying to match a given 'on' or 'off' period, an appropriate
+ * pair of 'change' and 'hold' times are chosen to get a close match.
+ * If the target delay is even, the 'change' number will be the
+ * smaller; if odd, the 'hold' number will be the smaller.
+
+ * Choosing pairs of delays with 12.5% errors allows us to match
+ * delays in the ranges: 56-72, 112-144, 168-216, 224-27504,
+ * 28560-36720.
+ * 26% of the achievable sums can be matched by multiple pairings.
+ * For example 1536 == 1536+0, 1024+512, or 768+768.
+ * This driver will always choose the pairing with the least
+ * maximum - 768+768 in this case.  Other pairings are not available.
  *
- * Access to the 3 levels and 2 blinks are on a first-come, first-served basis.
- * Access can be shared by multiple leds if they have the same level and
- * either same blink rates, or some don't blink.
- * When a led changes, it relinquishes access and tries again, so it might
- * lose access to hardware blink.
- * If a blink engine cannot be allocated, software blink is 

[PATCH - v2] LEDS: tca6507 - fix up some comments.

2013-11-12 Thread NeilBrown

In particular fix the capitalisation of GPIO and LED and
correct TCA6507_MAKE_CPIO, but also rewrite the comment about
platform-data to include reference to devicetree.

Also re-wrap comments to fit 80 columns.

Reported-by: Bryan Wu coolo...@gmail.com
Signed-off-by: NeilBrown ne...@suse.de

diff --git a/drivers/leds/leds-tca6507.c b/drivers/leds/leds-tca6507.c
index 93a2b1759054..503df834c690 100644
--- a/drivers/leds/leds-tca6507.c
+++ b/drivers/leds/leds-tca6507.c
@@ -4,77 +4,87 @@
  * The TCA6507 is a programmable LED controller that can drive 7
  * separate lines either by holding them low, or by pulsing them
  * with modulated width.
- * The modulation can be varied in a simple pattern to produce a blink or
- * double-blink.
+ * The modulation can be varied in a simple pattern to produce a
+ * blink or double-blink.
  *
- * This driver can configure each line either as a 'GPIO' which is out-only
- * (no pull-up) or as an LED with variable brightness and hardware-assisted
- * blinking.
+ * This driver can configure each line either as a 'GPIO' which is
+ * out-only (pull-up resistor required) or as an LED with variable
+ * brightness and hardware-assisted blinking.
  *
- * Apart from OFF and ON there are three programmable brightness levels which
- * can be programmed from 0 to 15 and indicate how many 500usec intervals in
- * each 8msec that the led is 'on'.  The levels are named MASTER, BANK0 and
- * BANK1.
+ * Apart from OFF and ON there are three programmable brightness
+ * levels which can be programmed from 0 to 15 and indicate how many
+ * 500usec intervals in each 8msec that the led is 'on'.  The levels
+ * are named MASTER, BANK0 and BANK1.
  *
- * There are two different blink rates that can be programmed, each with
- * separate time for rise, on, fall, off and second-off.  Thus if 3 or more
- * different non-trivial rates are required, software must be used for the 
extra
- * rates. The two different blink rates must align with the two levels BANK0 
and
- * BANK1.
- * This driver does not support double-blink so 'second-off' always matches
- * 'off'.
+ * There are two different blink rates that can be programmed, each
+ * with separate time for rise, on, fall, off and second-off.  Thus if
+ * 3 or more different non-trivial rates are required, software must
+ * be used for the extra rates. The two different blink rates must
+ * align with the two levels BANK0 and BANK1.  This driver does not
+ * support double-blink so 'second-off' always matches 'off'.
  *
- * Only 16 different times can be programmed in a roughly logarithmic scale 
from
- * 64ms to 16320ms.  To be precise the possible times are:
+ * Only 16 different times can be programmed in a roughly logarithmic
+ * scale from 64ms to 16320ms.  To be precise the possible times are:
  *0, 64, 128, 192, 256, 384, 512, 768,
  *1024, 1536, 2048, 3072, 4096, 5760, 8128, 16320
  *
- * Times that cannot be closely matched with these must be
- * handled in software.  This driver allows 12.5% error in matching.
+ * Times that cannot be closely matched with these must be handled in
+ * software.  This driver allows 12.5% error in matching.
  *
- * This driver does not allow rise/fall rates to be set explicitly.  When 
trying
- * to match a given 'on' or 'off' period, an appropriate pair of 'change' and
- * 'hold' times are chosen to get a close match.  If the target delay is even,
- * the 'change' number will be the smaller; if odd, the 'hold' number will be
- * the smaller.
-
- * Choosing pairs of delays with 12.5% errors allows us to match delays in the
- * ranges: 56-72, 112-144, 168-216, 224-27504, 28560-36720.
- * 26% of the achievable sums can be matched by multiple pairings. For example
- * 1536 == 1536+0, 1024+512, or 768+768.  This driver will always choose the
- * pairing with the least maximum - 768+768 in this case.  Other pairings are
- * not available.
+ * This driver does not allow rise/fall rates to be set explicitly.
+ * When trying to match a given 'on' or 'off' period, an appropriate
+ * pair of 'change' and 'hold' times are chosen to get a close match.
+ * If the target delay is even, the 'change' number will be the
+ * smaller; if odd, the 'hold' number will be the smaller.
+
+ * Choosing pairs of delays with 12.5% errors allows us to match
+ * delays in the ranges: 56-72, 112-144, 168-216, 224-27504,
+ * 28560-36720.
+ * 26% of the achievable sums can be matched by multiple pairings.
+ * For example 1536 == 1536+0, 1024+512, or 768+768.
+ * This driver will always choose the pairing with the least
+ * maximum - 768+768 in this case.  Other pairings are not available.
  *
- * Access to the 3 levels and 2 blinks are on a first-come, first-served basis.
- * Access can be shared by multiple leds if they have the same level and
- * either same blink rates, or some don't blink.
- * When a led changes, it relinquishes access and tries again, so it might
- * lose access to hardware blink.
- * If a blink engine cannot be