pinctrl: aspeed: Allow changing SPI mode from hardware strap defaults

Some platforms unfortunately have their SPI mode selection bits
strapped incorrectly (such as being configured for passthrough mode
when master mode is in fact the only useful configuration for it) and
thus require correction in software. Add the SPI mode bits to the
GPIO passthrough bits as the exceptions to the read-only rule for the
hardware strap register so that the pinctrl subsystem can be used for
such corrections.

Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Reviewed-by: Andrew Jeffery <andrew@codeconstruct.com.au>
Link: https://lore.kernel.org/r/20231005030849.11352-2-zev@bewilderbeest.net
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed: Use masks to describe pinconf bitfields

Since some of the AST2600 pinconf setting are not just single bit, modified
aspeed_pin_config @bit to @mask and add @mask to aspeed_pin_config_map to
support configuring multiple bits.

Signed-off-by: Johnny Huang <johnny_huang@aspeedtech.com>
[AJ: Tweak commit message]
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20191202061432.3996-7-andrew@aj.id.au
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed: Move aspeed_pin_config_map to separate source file

The AST2600 pinconf differs from the 2400 and 2500, aspeed_pin_config_map
should define separately, and add @confmaps and @nconfmaps to
aspeed_pinctrl_data structure for that change.

Signed-off-by: Johnny Huang <johnny_huang@aspeedtech.com>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20191202061432.3996-6-andrew@aj.id.au
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed: Add ASPEED_SB_PINCONF() helper

This helper macro is for declaring single bit (SB) mask pinconf,
and is used to prepare for modifying aspeed_pin_config
structure, the aspeed_pin_config structure @bit variable will be
modified to @mask.

This case is common in the AST2400/AST2500 which the mask is a single bit.

Signed-off-by: Johnny Huang <johnny_huang@aspeedtech.com>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20191202061432.3996-5-andrew@aj.id.au
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed: Document existence of deprecated compatibles

Otherwise they look odd in the face of not being listed in the bindings
documents.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20190724081313.12934-3-andrew@aj.id.au
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed: Add multiple pin group support for functions

The AST2400 and AST2500 SoCs only exposed one pin group per function.
Lone pin groups drove some implementation simplifications in the ASPEED
pinmux infrastructure that is now invalid for the AST2600, which
supports multiple groups per function for some functions on the chip
(SMBus Alert pins and UARTs among others).

This patch reworks the macro jungle to enable support for multiple pin
groups. In the process we inflict some collateral damage on the existing
AST2400 and AST2500 drivers, but the rework is mostly a relatively
straight-forward, automated transform of adding the pin name as an
argument to some macro calls and implementing wrappers to paper over
groups in the cases where there aren't multiple.

As previously documented, the macro infrastructure exposes mux
configuration as symbols in the source file which are used to detect
accidental duplication. Previously these symbols were named in terms of
the signal for a given expression. As the AST2600 supports multiple pin
groups for a function, the signal name on its own is no-longer unique,
and we must switch to the (signal, group) tuple. However, this means
that we can no-longer derive the signal expression symbol name from the
signal name alone, which among other cases, impacts the operation of the
PIN_DECL_x() macros.

To fix that and avoid requiring we awkwardly provide the associated
group name for every signal for every PIN_DECL_x() invocation, instead
opportunistically alias the name of the signal expression symbol from
the unique (signal, group) tuple to the also unique (pin, signal) tuple,
then reference the alias symbol in the tables generated by PIN_DECL_x().
This way we do not require extra group parameters for PIN_DECL_x() as
the pin name was already provided as an argument, and instead simply
require that the pin name be provided to the expression declaration
macros in order to generate the alias symbol.

The patch implements the alias strategy and fixes up all the expression
definition macro calls in the AST2400 and AST2500 drivers to account for
pin groups. Given the implementation strategy has the property that
compilation either fails or loudly warns for bad pin descriptions, this
patch is theoretically tested by successfully compiling both affected
drivers. For a more practical test I've inspected the diff of the
content of the pinctrl debugfs entries before and after the patch under
qemu; all pins, functions and groups match.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20190729055604.13239-5-andrew@aj.id.au
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed: Rename pin declaration macros

Rename macros as follows:

* s/SS_PIN_DECL()/PIN_DECL_1()/
* s/MS_PIN_DECL()/PIN_DECL_2()/
* s/MS_PIN_DECL_()/PIN_DECL_()/

This is in preparation for adding PIN_DECL_3(). We could clean this up
with e.g. CPPMAGIC_MAP() from ccan, but that might be a bridge too far
given how much of a macro jungle we already have.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20190729055604.13239-3-andrew@aj.id.au
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed-g5: Delay acquisition of regmaps

While sorting out some devicetree issues I found that the pinctrl driver
was failing to acquire its GFX regmap even though the phandle was
present in the devicetree:

[ 0.124190] aspeed-g5-pinctrl 1e6e2000.syscon:pinctrl: No GFX phandle found, some mux configurations may fail

Without access to the GFX regmap we fail to configure the mux for the
VPO function:

[ 1.548866] pinctrl core: add 1 pinctrl maps
[ 1.549826] aspeed-g5-pinctrl 1e6e2000.syscon:pinctrl: found group selector 164 for VPO
[ 1.550638] aspeed-g5-pinctrl 1e6e2000.syscon:pinctrl: request pin 144 (V20) for 1e6e6000.display
[ 1.551346] aspeed-g5-pinctrl 1e6e2000.syscon:pinctrl: request pin 145 (U19) for 1e6e6000.display
...
[ 1.562057] aspeed-g5-pinctrl 1e6e2000.syscon:pinctrl: request pin 218 (T22) for 1e6e6000.display
[ 1.562541] aspeed-g5-pinctrl 1e6e2000.syscon:pinctrl: request pin 219 (R20) for 1e6e6000.display
[ 1.563113] Muxing pin 144 for VPO
[ 1.563456] Want SCU8C[0x00000001]=0x1, got 0x0 from 0x00000000
[ 1.564624] aspeed_gfx 1e6e6000.display: Error applying setting, reverse things back

This turned out to be a simple problem of timing: The ASPEED pinctrl
driver is probed during arch_initcall(), while GFX is processed much
later. As such the GFX syscon is not yet registered during the pinctrl
probe() and we get an -EPROBE_DEFER when we try to look it up, however
we must not defer probing the pinctrl driver for the inability to mux
some GFX-related functions.

Switch to lazily grabbing the regmaps when they're first required by the
mux configuration. This generates a bit of noise in the patch as we have
to drop the `const` qualifier on arguments for several function
prototypes, but has the benefit of working.

I've smoke tested this for the ast2500-evb under qemu with a dummy
graphics device. We now succeed in our attempts to configure the SoC's
VPO pinmux function.

Fixes: 7d29ed88acbb ("pinctrl: aspeed: Read and write bits in LPC and GFX controllers")
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20190724080155.12209-1-andrew@aj.id.au
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed: Split out pinmux from general pinctrl

ASPEED have completely rearranged the System Control Unit register
layout with the AST2600. The existing code took advantage of the fact
that the AST2400 and AST2500 had layouts that were similar enough to
have little impact on the pinmux infrastructure (though there is a wart
with read-modify-write vs write-1-clear semantics of the hardware
strapping registers between the two).

Given that any similarity has been thrown out with the AST2600, separate
out the function applying an expression state to be driver-specific.
With it, extract out the pinmux macro jungle to its own header and
implementation so the pieces can be composed without dependency cycles.

Cc: Johnny Huang <johnny_huang@aspeedtech.com>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20190628023838.15426-8-andrew@aj.id.au
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

pinctrl: aspeed: g4: constify pinconf_ops, pinctrl_ops, and pinmux_ops structures

These structures are only stored in fields of a pinctrl_desc
structure (pctlops, and pmxops) that are const. Make the
structures const as well.

Done with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed: g4: Add USB device and host support

Implement the AST2400 USB functions as described by the devicetree
bindings. Three ports are fully documented in the datasheet and exposed
through the bindings and pinctrl, though there are remnants of
documentation for a fourth port muxed with GPIO pins GPIOQ6 and GPIOQ7.
The implementation is updated to reflect this but the function and
group are not exposed.

Disregarding the mostly undocumented fourth port, the USB functions are
an outlier with respect to the rest of the muxed functionality on the
AST2400 as GPIO is not supported on these pins.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed: g4: Add pinconf support

Testing for pinctrl-aspeed-g4 was performed on an OpenPOWER Palmetto
system, using the strategy outlined in the commit message for the
change to the Aspeed pinctrl core.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed: Fix unused-const-variable warnings

Three video input signals suffered from a search/replace failure in
some copied code.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed: g4: Fix mux configuration for GPIOs AA[4-7], AB[0-7]

Incorrect video output configuration bits were being tested on pins in
GPIO banks AA and AB for the ROM{8,16} mux functions. The ROM{8,16}
functions are the highest priority for the relevant pins and also the
default function, so we require the relevant video output configuration
be disabled to mux GPIO functionality. As the wrong bits were being
tested a GPIO export would succeed but leave the pin in an unresponsive
state (i.e. value updates were ignored).

This misbehaviour was discovered as part of extending the GPIO
controller's support to cover banks Y, Z, AA, AB and AC (AC in the case
of the g5 SoC).

Fixes: 6d329f14a75f ("pinctrl: aspeed-g4: Add mux configuration for all pins")
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed-g4: Add mux configuration for all pins

The patch introducing the g4 pinctrl driver implemented a smattering of
pins to flesh out the implementation of the core and provide bare-bones
support for some OpenPOWER platforms. Now, update the bindings document
to reflect the complete functionality and implement the necessary pin
configuration tables in the driver.

Cc: Timothy Pearson <tpearson@raptorengineering.com>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Acked-by: Joel Stanley <joel@jms.id.au>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: aspeed: Read and write bits in LPC and GFX controllers

The System Control Unit IP block in the Aspeed SoCs is typically where
the pinmux configuration is found, but not always. A number of pins
depend on state in one of LPC Host Control (LHC) or SoC Display
Controller (GFX) IP blocks, so the Aspeed pinmux drivers should have the
means to adjust these as necessary.

We use syscon to cast a regmap over the GFX and LPC blocks, which is
used as an arbitration layer between the relevant driver and the pinctrl
subsystem. The regmaps are then exposed to the SoC-specific pinctrl
drivers by phandles in the devicetree, and are selected during a mux
request by querying a new 'ip' member in struct aspeed_sig_desc.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl: Add pinctrl-aspeed-g4 driver

A subset of the pins and functions are exposed. The selection of
functions and pins is driven by the development of OpenBMC[1] on the
AST2400 SoC, particularly around booting the OpenPOWER Palmetto
development machine.

[1] https://github.com/openbmc/docs

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>