spmi: Return meaningful errors in spmi_controller_alloc()

spmi_controller_alloc() currently returns NULL to all types of errors,
which can be improved.

Use appropriate error code in returns and pass the errors from used
functions where possible.

Signed-off-by: Fei Shao <fshao@chromium.org>
Link: https://lore.kernel.org/r/20230824104101.4083400-6-fshao@chromium.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/20231206231733.4031901-8-sboyd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spmi: rename spmi device lookup helper

Rename the SPMI device helper which is used to lookup a device from its
OF node as spmi_find_device_by_of_node() so that it reflects the
implementation and matches how other helpers like this are named.

This will specifically make it more clear that this is a lookup function
which returns a reference counted structure.

Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/20231003152927.15000-6-johan+linaro@kernel.org
Signed-off-by: Lee Jones <lee@kernel.org>

spmi: document spmi_device_from_of() refcounting

Add a comment documenting that the spmi_device_from_of() takes a
reference to the embedded struct device that needs to be dropped after
use.

Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/20231003152927.15000-5-johan+linaro@kernel.org
Signed-off-by: Lee Jones <lee@kernel.org>

spmi: Add a check for remove callback when removing a SPMI driver

When removing a SPMI driver, there can be a crash due to NULL pointer
dereference if it does not have a remove callback defined. This is
one such call trace observed when removing the QCOM SPMI PMIC driver:

dump_backtrace.cfi_jt+0x0/0x8
dump_stack_lvl+0xd8/0x16c
panic+0x188/0x498
__cfi_slowpath+0x0/0x214
__cfi_slowpath+0x1dc/0x214
spmi_drv_remove+0x16c/0x1e0
device_release_driver_internal+0x468/0x79c
driver_detach+0x11c/0x1a0
bus_remove_driver+0xc4/0x124
driver_unregister+0x58/0x84
cleanup_module+0x1c/0xc24 [qcom_spmi_pmic]
__do_sys_delete_module+0x3ec/0x53c
__arm64_sys_delete_module+0x18/0x28
el0_svc_common+0xdc/0x294
el0_svc+0x38/0x9c
el0_sync_handler+0x8c/0xf0
el0_sync+0x1b4/0x1c0

If a driver has all its resources allocated through devm_() APIs and
does not need any other explicit cleanup, it would not require a
remove callback to be defined. Hence, add a check for remove callback
presence before calling it when removing a SPMI driver.

Link: https://lore.kernel.org/r/1671601032-18397-2-git-send-email-quic_jprakash@quicinc.com
Fixes: 6f00f8c8635f ("mfd: qcom-spmi-pmic: Use devm_of_platform_populate()")
Fixes: 5a86bf343976 ("spmi: Linux driver framework for SPMI")
Signed-off-by: Jishnu Prakash <quic_jprakash@quicinc.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/20230413223834.4084793-7-sboyd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spmi: fix W=1 kernel-doc warnings

Fix all W=1 kernel-doc warnings in drivers/spmi/:

drivers/spmi/spmi.c:414: warning: expecting prototype for spmi_controller_alloc(). Prototype was for spmi_device_alloc() instead
drivers/spmi/spmi.c:592: warning: expecting prototype for spmi_driver_register(). Prototype was for __spmi_driver_register() instead
drivers/spmi/spmi.c:592: warning: Function parameter or member 'owner' not described in '__spmi_driver_register'
drivers/spmi/spmi-pmic-arb.c:155: warning: cannot understand function prototype: 'struct spmi_pmic_arb '
drivers/spmi/spmi-pmic-arb.c:203: warning: cannot understand function prototype: 'struct pmic_arb_ver_ops '
drivers/spmi/spmi-pmic-arb.c:219: warning: expecting prototype for struct pmic_arb_ver. Prototype was for struct pmic_arb_ver_ops instead

Link: https://lore.kernel.org/r/20230113064040.26801-1-rdunlap@infradead.org
Cc: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/20230413223834.4084793-6-sboyd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

driver core: make struct bus_type.uevent() take a const *

The uevent() callback in struct bus_type should not be modifying the
device that is passed into it, so mark it as a const * and propagate the
function signature changes out into all relevant subsystems that use
this callback.

Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230111113018.459199-16-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers: spmi: Directly use ida_alloc()/free()

Use ida_alloc()/ida_free() instead of deprecated
ida_simple_get()/ida_simple_remove() .

Signed-off-by: keliu <liuke94@huawei.com>
Link: https://lore.kernel.org/r/20220527071338.2359733-1-liuke94@huawei.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/20220930005019.2663064-2-sboyd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spmi: add a helper to look up an SPMI device from a device node

The helper function spmi_device_from_of() takes a device node and
returns the SPMI device associated with it.
This is like of_find_device_by_node but for SPMI devices.

Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/20220429220904.137297-2-caleb.connolly@linaro.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

bus: Make remove callback return void

The driver core ignores the return value of this callback because there
is only little it can do when a device disappears.

This is the final bit of a long lasting cleanup quest where several
buses were converted to also return void from their remove callback.
Additionally some resource leaks were fixed that were caused by drivers
returning an error code in the expectation that the driver won't go
away.

With struct bus_type::remove returning void it's prevented that newly
implemented buses return an ignored error code and so don't anticipate
wrong expectations for driver authors.

Reviewed-by: Tom Rix <trix@redhat.com> (For fpga)
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com> (For drivers/s390 and drivers/vfio)
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> (For ARM, Amba and related parts)
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Chen-Yu Tsai <wens@csie.org> (for sunxi-rsb)
Acked-by: Pali Rohár <pali@kernel.org>
Acked-by: Mauro Carvalho Chehab <mchehab@kernel.org> (for media)
Acked-by: Hans de Goede <hdegoede@redhat.com> (For drivers/platform)
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-By: Vinod Koul <vkoul@kernel.org>
Acked-by: Juergen Gross <jgross@suse.com> (For xen)
Acked-by: Lee Jones <lee.jones@linaro.org> (For mfd)
Acked-by: Johannes Thumshirn <jth@kernel.org> (For mcb)
Acked-by: Johan Hovold <johan@kernel.org>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> (For slimbus)
Acked-by: Kirti Wankhede <kwankhede@nvidia.com> (For vfio)
Acked-by: Maximilian Luz <luzmaximilian@gmail.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> (For ulpi and typec)
Acked-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com> (For ipack)
Acked-by: Geoff Levand <geoff@infradead.org> (For ps3)
Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com> (For thunderbolt)
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> (For intel_th)
Acked-by: Dominik Brodowski <linux@dominikbrodowski.net> (For pcmcia)
Acked-by: Rafael J. Wysocki <rafael@kernel.org> (For ACPI)
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org> (rpmsg and apr)
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> (For intel-ish-hid)
Acked-by: Dan Williams <dan.j.williams@intel.com> (For CXL, DAX, and NVDIMM)
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com> (For isa)
Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (For firewire)
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> (For hid)
Acked-by: Thorsten Scherer <t.scherer@eckelmann.de> (For siox)
Acked-by: Sven Van Asbroeck <TheSven73@gmail.com> (For anybuss)
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> (For MMC)
Acked-by: Wolfram Sang <wsa@kernel.org> # for I2C
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Finn Thain <fthain@linux-m68k.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210713193522.1770306-6-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spmi: Add driver shutdown support

Add new shutdown() method. Use it in the standard driver model style.

Link: https://lore.kernel.org/r/1603187810-30481-2-git-send-email-hsin-hsiung.wang@mediatek.com
Signed-off-by: Hsin-Hsiung Wang <hsin-hsiung.wang@mediatek.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/20201210023344.2838141-4-sboyd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spmi: fix some coding style issues at the spmi core

While preparing to port the HiSilicon 6421v600 SPMI driver,
I noticed some coding style issues at the SPMI core.

Address them.

Link: https://lore.kernel.org/r/fec878502147336cbf2cf86e476e9dd797cd7e6f.1601360391.git.mchehab+huawei@kernel.org
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/20201210023344.2838141-3-sboyd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spmi: get rid of a warning when built with W=1

The SPMI core complaing with this warning when built with W=1:

drivers/spmi/spmi.c: In function ‘spmi_controller_remove’:
drivers/spmi/spmi.c:548:6: warning: variable ‘dummy’ set but not used [-Wunused-but-set-variable]
548 | int dummy;
| ^~~~~

As the dummy var isn't needed, remove it.

Link: https://lore.kernel.org/r/aacfd03835b7d1b3b6c21665b44000fe7242e535.1601360391.git.mchehab+huawei@kernel.org
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/20201210023344.2838141-2-sboyd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 284

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 version 2 and
only version 2 as published by the free software foundation this
program is distributed in the hope that it will be useful but
without any warranty without even the implied warranty of
merchantability or fitness for a particular purpose see the gnu
general public license for more details

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 294 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.825281744@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spmi: Convert to using %pOF instead of full_name

Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spmi: Include OF based modalias in device uevent

Include the OF-based modalias in the uevent sent when registering SPMI
devices, so that user space has a chance to autoload the kernel module
for the device.

Tested-by: Rob Clark <robdclark@gmail.com>
Reported-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spmi: do not use bus internal data

The variable p is a data structure which is used by the driver core
internally and it is not expected that busses will be directly accessing
these driver core internal only data.

Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spmi: Auto-populate driver.owner in spmi_driver_register()

Populate the owner field of the spmi driver when
spmi_driver_register() is called in a similar fashion to how
other *_driver_register() functions do it. This saves driver
writers from having to do this themselves.

Cc: Andy Gross <agross@codeaurora.org>
Cc: Gilad Avidov <gavidov@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spmi: add command tracepoints for SPMI

Add tracepoints to retrieve information about read, write
and non-data commands. For performance measurement support
tracepoints are added at the beginning and at the end of
transfers. Following is a list showing the new tracepoint
events. The "cmd" parameter here represents the opcode, SID,
and full 16-bit address.

spmi_write_begin: cmd and data buffer.
spmi_write_end : cmd and return value.
spmi_read_begin : cmd.
spmi_read_end : cmd, return value and data buffer.
spmi_cmd : cmd.

The reason that cmd appears at both the beginning and at
the end event is that SPMI drivers can request commands
concurrently. cmd helps in matching the corresponding
events.

SPMI tracepoints can be enabled like:

echo 1 >/sys/kernel/debug/tracing/events/spmi/enable

and will dump messages that can be viewed in
/sys/kernel/debug/tracing/trace that look like:

... spmi_read_begin: opc=56 sid=00 addr=0x0000
... spmi_read_end: opc=56 sid=00 addr=0x0000 ret=0 len=02 buf=0x[01-40]
... spmi_write_begin: opc=48 sid=00 addr=0x0000 len=3 buf=0x[ff-ff-ff]

Suggested-by: Sagar Dharia <sdharia@codeaurora.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Gilad Avidov <gavidov@codeaurora.org>
Signed-off-by: Ankit Gupta <ankgupta@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spmi: remove wakeup command before slave probe

According to spmi spec a slave powers up into startup state and then
transitions into active state. Thus, the wakeup command is not required
before calling the slave's probe. The wakeup command is only needed for
slaves that are in sleep state after receiving the sleep command.

Cc: galak@codeaurora.org
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Reviewed-by: Sagar Dharia <sdharia@codeaurora.org>
Acked-by: Josh Cartwright <joshc@eso.teric.us>
Signed-off-by: Gilad Avidov <gavidov@codeaurora.org>
Tested-by: Ivan T. Ivanov <iivanov@mm-sol.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spmi: Remove duplicate inclusion of module.h

module.h was included twice.

Signed-off-by: Sachin Kamat <sachin.kamat@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spmi: pm: drop bus-level PM suspend/resume routines

SPMI defines the behavior of a device in the "SLEEP" state as being
"user-defined or specified by the device manufacturer". Without
clearly-defined bus-level semantics for low-power states, push the
responsibility of transitioning a device into/out of "SLEEP" into SPMI
device drivers.

Cc: Felipe Balbi <balbi@ti.com>
Signed-off-by: Josh Cartwright <joshc@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

spmi: Linux driver framework for SPMI

System Power Management Interface (SPMI) is a specification
developed by the MIPI (Mobile Industry Process Interface) Alliance
optimized for the real time control of Power Management ICs (PMIC).

SPMI is a two-wire serial interface that supports up to 4 master
devices and up to 16 logical slaves.

The framework supports message APIs, multiple busses (1 controller
per bus) and multiple clients/slave devices per controller.

Signed-off-by: Kenneth Heitke <kheitke@codeaurora.org>
Signed-off-by: Michael Bohan <mbohan@codeaurora.org>
Signed-off-by: Josh Cartwright <joshc@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>