Commit Graph

5 Commits

Author SHA1 Message Date
Masahiro Yamada
3b05b5f0e4 pinctrl: uniphier: support per-pin input enable for new SoCs
Upcoming new pinctrl drivers for PH1-LD11 and PH-LD20 support input
signal gating for each pin.  (While, existing ones only support it
per pin-group.)  This commit prepares the core part for that.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2016-04-01 00:56:07 +09:00
Masahiro Yamada
8cc92b996d pinctrl: uniphier: introduce capability flag
The core part of the UniPhier pinctrl driver needs to support a new
capability for upcoming UniPhier ARMv8 SoCs.  This sometimes happens
because pinctrl drivers include really SoC-specific stuff.

This commit intends to tidy up SoC-specific parameters of the existing
drivers before adding new ones.  Having flags would be better than
adding new members every time a new SoC-specific capability comes up.

At this time, there is one flag, UNIPHIER_PINCTRL_CAPS_DBGMUX_SEPARATE.
This capability (I'd say rather quirk) was added for PH1-Pro4 and
PH1-Pro5 as requirement from our customer.  For those SoCs, one pin-mux
setting is controlled by the combination of two separate registers; the
LSB bits at register offset (8 * N) and the MSB bits at (8 * N + 4).
Because it is impossible to update two separate registers atomically,
the LOAD_PINCTRL register should be set in order to make the pin-mux
settings really effective.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2016-04-01 00:54:00 +09:00
Masahiro Yamada
510454db04 pinctrl: uniphier: use devm_get_addr() to get base address
Currently, fdtdec_get_addr_size() does not support the address
translation, so it cannot handle device trees with non-straight
"ranges" properties.  (This would be a problem with DTS for UniPhier
ARMv8 SoCs.)

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2016-04-01 00:17:25 +09:00
Masahiro Yamada
fdd15b6a86 pinctrl: uniphier: set input-enable before pin-muxing
While IECTRL is disabled, input signals are pulled-down internally.
If pin-muxing is set up first, glitch signals (Low to High transition)
might be input to hardware blocks.

Bad case scenario:
[1] The hardware block is already running before pinctrl is handled.
   (the reset is de-asserted by default or by a firmware, for example)
[2] The pin-muxing is set up.  The input signals to hardware block
   are pulled-down by the chip-internal biasing.
[3] The pins are input-enabled.  The signals from the board reach the
    hardware block.

Actually, one invalid character is input to the UART blocks for such
SoCs as PH1-LD4, PH1-sLD8, where UART devices start to run at the
power on reset.

To avoid such problems, pins should be input-enabled before muxing.

[ ported from Linux commit bac7f4c1bf5e7c6ccd5bb71edc015b26c77f7460 ]

Fixes: 5dc626f836 ("pinctrl: uniphier: add UniPhier pinctrl core support")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2016-03-09 01:10:52 +09:00
Masahiro Yamada
5dc626f836 pinctrl: uniphier: add UniPhier pinctrl core support
The core support for the pinctrl drivers for all the UniPhier SoCs.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2015-09-23 23:21:32 +09:00