f59b6f9f32
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> |
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| acpi | ||
| asm-generic | ||
| crypto | ||
| drm | ||
| keys | ||
| linux | ||
| math-emu | ||
| media | ||
| mtd | ||
| net | ||
| pcmcia | ||
| rdma | ||
| rxrpc | ||
| scsi | ||
| sound | ||
| target | ||
| trace | ||
| video | ||
| xen | ||
| Kbuild | ||