Commit Graph

3 Commits

Author SHA1 Message Date
Magnus Damm
2b67c95b74 drivers/leds/leds-renesas-tpu.c: move Renesas TPU LED driver platform data
Use the platform_data include directory for the TPU LED driver, as
suggested by Paul Mundt.

Signed-off-by: Magnus Damm <damm@opensource.se>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:55 -07:00
Magnus Damm
02c3294174 drivers/leds/leds-renesas-tpu.c: update driver to use workqueue
Use a workqueue in the Renesas TPU LED driver to allow the Runtime PM code
to sleep.

Signed-off-by: Magnus Damm <damm@opensource.se>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:55 -07:00
Magnus Damm
f59b6f9f32 leds: Renesas TPU LED driver
Add V2 of the LED driver for a single timer channel for the TPU hardware
block commonly found in Renesas SoCs.

The driver has been written with optimal Power Management in mind, so to
save power the LED is driven as a regular GPIO pin in case of maximum
brightness and power off which allows the TPU hardware to be idle and
which in turn allows the clocks to be stopped and the power domain to be
turned off transparently.

Any other brightness level requires use of the TPU hardware in PWM mode.
TPU hardware device clocks and power are managed through Runtime PM.
System suspend and resume is known to be working - during suspend the LED
is set to off by the generic LED code.

The TPU hardware timer is equipeed with a 16-bit counter together with an
up-to-divide-by-64 prescaler which makes the hardware suitable for
brightness control.  Hardware blink is unsupported.

The LED PWM waveform has been verified with a Fluke 123 Scope meter on a
sh7372 Mackerel board.  Tested with experimental sh7372 A3SP power domain
patches.  Platform device bind/unbind tested ok.

V2 has been tested on the DS2 LED of the sh73a0-based AG5EVM.

[axel.lin@gmail.com: include linux/module.h]
Signed-off-by: Magnus Damm <damm@opensource.se>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:54 -07:00