History log of /linux-master/drivers/mfd/qcom-pm8xxx.c
Revision Date Author Comments
# 19ea1d39 23-Nov-2023 Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

mfd: qcom-pm8xxx: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20231123165627.492259-14-u.kleine-koenig@pengutronix.de
Signed-off-by: Lee Jones <lee@kernel.org>


# f1a63db6 20-Jul-2023 Chengfeng Ye <dg573847474@gmail.com>

mfd: qcom-pm8xxx: Fix potential deadlock on &chip->pm_irq_lock

As &chip->pm_irq_lock is acquired by pm8xxx_irq_handler() under irq
context, other process context code should disable irq before acquiring
the lock.

Since .irq_set_type and .irq_get_irqchip_state callbacks are generally
executed from process context without irq disabled by default, the same
lock acquision should disable irq.

Possible deadlock scenario
pm8xxx_irq_set_type()
-> pm8xxx_config_irq()
-> spin_lock(&chip->pm_irq_lock)
<irq interrupt>
-> pm8xxx_irq_handler()
-> pm8xxx_irq_master_handler()
-> pm8xxx_irq_block_handler()
-> pm8xxx_read_block_irq()
-> spin_lock(&chip->pm_irq_lock) (deadlock here)

This flaw was found using an experimental static analysis tool we are
developing for irq-related deadlock.

Fix the potential deadlock by spin_lock_irqsave().

Signed-off-by: Chengfeng Ye <dg573847474@gmail.com>
Reviewed-by: Bjorn Andersson <quic_bjorande@quicinc.com>
Link: https://lore.kernel.org/r/20230720071330.50382-1-dg573847474@gmail.com
Signed-off-by: Lee Jones <lee@kernel.org>


# 49184844 27-Dec-2022 Jiapeng Chong <jiapeng.chong@linux.alibaba.com>

mfd: qcom-pm8xxx: Remove set but unused variable 'rev'

Variable rev is not effectively used in the function, so delete it.

drivers/mfd/qcom-pm8xxx.c:513:6: warning: variable 'rev' set but not used.

Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=3558
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20221227081921.56448-1-jiapeng.chong@linux.alibaba.com


# 727b67e3 21-Oct-2022 Neil Armstrong <neil.armstrong@linaro.org>

mfd: qcom-pm8xxx: Drop unused PM8018 compatible

The PM8018 compatible is always used with PM8921 fallback, so PM8018
compatible can be safely removed from device ID table

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20220928-mdm9615-dt-schema-fixes-v4-8-dac2dfaac703@linaro.org


# d3546ccd 25-Sep-2021 Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

mfd: qcom-pm8xxx: switch away from using chained IRQ handlers

PM8xxx PMIC family uses GPIO as parent IRQ. Using it together with the
irq_set_chained_handler_and_data() results in warnings from the GPIOLIB
(see 461c1a7d4733 ("gpiolib: override irq_enable/disable"))
as in this path the IRQ resources are not allocated (and thus the
corresponding GPIO is not marked as used for the IRQ. Use request_irq so
that the IRQ resources are proprely setup.

[ 0.803271] ------------[ cut here ]------------
[ 0.803338] WARNING: CPU: 3 PID: 1 at drivers/gpio/gpiolib.c:3207 gpiochip_enable_irq+0xa4/0xa8
[ 0.803470] Modules linked in:
[ 0.803542] CPU: 3 PID: 1 Comm: swapper/0 Not tainted 5.14.0-rc6-next-20210820-postmarketos-qcom-apq8064+ #1
[ 0.803645] Hardware name: Generic DT based system
[ 0.803710] Backtrace:
[ 0.803777] [<c0e3493c>] (dump_backtrace) from [<c0e34d00>] (show_stack+0x20/0x24)
[ 0.803911] r7:00000c87 r6:c07062dc r5:60000093 r4:c11d0f54
[ 0.803980] [<c0e34ce0>] (show_stack) from [<c0e38314>] (dump_stack_lvl+0x48/0x54)
[ 0.804097] [<c0e382cc>] (dump_stack_lvl) from [<c0e38338>] (dump_stack+0x18/0x1c)
[ 0.804217] r5:00000009 r4:c11fe208
[ 0.804274] [<c0e38320>] (dump_stack) from [<c03219c8>] (__warn+0xfc/0x114)
[ 0.804387] [<c03218cc>] (__warn) from [<c0e35334>] (warn_slowpath_fmt+0x74/0xd0)
[ 0.804509] r7:c07062dc r6:00000c87 r5:c11fe208 r4:00000000
[ 0.804577] [<c0e352c4>] (warn_slowpath_fmt) from [<c07062dc>] (gpiochip_enable_irq+0xa4/0xa8)
[ 0.804716] r8:c27b6200 r7:c27aec00 r6:c27aec18 r5:cf77a448 r4:c02225f0
[ 0.804789] [<c0706238>] (gpiochip_enable_irq) from [<c0706348>] (gpiochip_irq_enable+0x28/0x38)
[ 0.804921] r5:cf77a448 r4:c27aec18
[ 0.804977] [<c0706320>] (gpiochip_irq_enable) from [<c03897a0>] (irq_enable+0x48/0x78)
[ 0.805111] r5:00000000 r4:c27aec00
[ 0.805167] [<c0389758>] (irq_enable) from [<c0389850>] (__irq_startup+0x80/0xbc)
[ 0.805286] r5:00000000 r4:c27aec00
[ 0.805343] [<c03897d0>] (__irq_startup) from [<c038996c>] (irq_startup+0xe0/0x18c)
[ 0.805468] r7:c27aec00 r6:00000001 r5:00000000 r4:c27aec00
[ 0.805535] [<c038988c>] (irq_startup) from [<c0389a54>] (irq_activate_and_startup+0x3c/0x74)
[ 0.805669] r7:c27aec00 r6:00000001 r5:c27aec00 r4:00000000
[ 0.805736] [<c0389a18>] (irq_activate_and_startup) from [<c0389b58>] (__irq_do_set_handler+0xcc/0x1c0)
[ 0.805875] r7:c27aec00 r6:c0383710 r5:c08a16b0 r4:00000001
[ 0.805943] [<c0389a8c>] (__irq_do_set_handler) from [<c0389d80>] (irq_set_chained_handler_and_data+0x60/0x98)
[ 0.806087] r7:c27b5c10 r6:c27aed40 r5:c08a16b0 r4:c27aec00
[ 0.806154] [<c0389d20>] (irq_set_chained_handler_and_data) from [<c08a1660>] (pm8xxx_probe+0x1fc/0x24c)
[ 0.806298] r6:0000003a r5:0000003a r4:c27b5c00
[ 0.806359] [<c08a1464>] (pm8xxx_probe) from [<c0871420>] (platform_probe+0x6c/0xc8)
[ 0.806495] r10:c2507080 r9:e8bea2cc r8:c165e0e0 r7:c165e0e0 r6:c15f08f8 r5:c27b5c10
[ 0.806582] r4:00000000
[ 0.806632] [<c08713b4>] (platform_probe) from [<c086e280>] (really_probe+0xe8/0x460)
[ 0.806769] r7:c165e0e0 r6:c15f08f8 r5:00000000 r4:c27b5c10
[ 0.806837] [<c086e198>] (really_probe) from [<c086e6a8>] (__driver_probe_device+0xb0/0x22c)
[ 0.806975] r7:c27b5c10 r6:cf70fba4 r5:c15f08f8 r4:c27b5c10
[ 0.807042] [<c086e5f8>] (__driver_probe_device) from [<c086e868>] (driver_probe_device+0x44/0xe0)
[ 0.807188] r9:e8bea2cc r8:00000000 r7:c27b5c10 r6:cf70fba4 r5:c16ae4b4 r4:c16ae4b0
[ 0.807271] [<c086e824>] (driver_probe_device) from [<c086ecd8>] (__device_attach_driver+0xb4/0x12c)
[ 0.807421] r9:e8bea2cc r8:c15eec08 r7:c27b5c10 r6:cf70fba4 r5:c15f08f8 r4:00000001
[ 0.807506] [<c086ec24>] (__device_attach_driver) from [<c086c06c>] (bus_for_each_drv+0x94/0xe4)
[ 0.807651] r7:c16ae484 r6:c086ec24 r5:cf70fba4 r4:00000000
[ 0.807718] [<c086bfd8>] (bus_for_each_drv) from [<c086e0e0>] (__device_attach+0x104/0x19c)
[ 0.807852] r6:00000001 r5:c27b5c54 r4:c27b5c10
[ 0.807913] [<c086dfdc>] (__device_attach) from [<c086eef4>] (device_initial_probe+0x1c/0x20)
[ 0.808050] r6:c27b5c10 r5:c15ef1b0 r4:c27b5c10
[ 0.808111] [<c086eed8>] (device_initial_probe) from [<c086d00c>] (bus_probe_device+0x94/0x9c)
[ 0.808240] [<c086cf78>] (bus_probe_device) from [<c086a60c>] (device_add+0x404/0x8f4)
[ 0.808370] r7:c16ae484 r6:c251ba10 r5:00000000 r4:c27b5c10
[ 0.808439] [<c086a208>] (device_add) from [<c0a82f50>] (of_device_add+0x44/0x4c)
[ 0.808581] r10:c144c854 r9:00000001 r8:e8bea314 r7:c251ba10 r6:00000000 r5:00000000
[ 0.808669] r4:c27b5c00
[ 0.808718] [<c0a82f0c>] (of_device_add) from [<c0a836cc>] (of_platform_device_create_pdata+0xa0/0xc8)
[ 0.808850] [<c0a8362c>] (of_platform_device_create_pdata) from [<c0a83908>] (of_platform_bus_create+0x1f0/0x514)
[ 0.809005] r9:00000001 r8:c251ba10 r7:00000000 r6:00000000 r5:00000000 r4:e8bea2b0
[ 0.809086] [<c0a83718>] (of_platform_bus_create) from [<c0a83e04>] (of_platform_populate+0x98/0x128)
[ 0.809233] r10:c144c854 r9:00000001 r8:c251ba10 r7:00000000 r6:00000000 r5:e8bea170
[ 0.809321] r4:e8bea2b0
[ 0.809371] [<c0a83d6c>] (of_platform_populate) from [<c0a83f20>] (devm_of_platform_populate+0x60/0xa8)
[ 0.809521] r9:0000011d r8:c165e0e0 r7:e8bea170 r6:c2c34f40 r5:c2cac140 r4:c251ba10
[ 0.809604] [<c0a83ec0>] (devm_of_platform_populate) from [<c08a212c>] (ssbi_probe+0x138/0x16c)
[ 0.809738] r6:c2c34f40 r5:c251ba10 r4:ff822700
[ 0.809800] [<c08a1ff4>] (ssbi_probe) from [<c0871420>] (platform_probe+0x6c/0xc8)
[ 0.809923] r7:c165e0e0 r6:c15f0a80 r5:c251ba10 r4:00000000
[ 0.809989] [<c08713b4>] (platform_probe) from [<c086e280>] (really_probe+0xe8/0x460)
[ 0.810120] r7:c165e0e0 r6:c15f0a80 r5:00000000 r4:c251ba10
[ 0.810187] [<c086e198>] (really_probe) from [<c086e6a8>] (__driver_probe_device+0xb0/0x22c)
[ 0.810325] r7:c251ba10 r6:c15f0a80 r5:c15f0a80 r4:c251ba10
[ 0.810393] [<c086e5f8>] (__driver_probe_device) from [<c086e868>] (driver_probe_device+0x44/0xe0)
[ 0.810539] r9:0000011d r8:00000000 r7:c251ba10 r6:c15f0a80 r5:c16ae4b4 r4:c16ae4b0
[ 0.810623] [<c086e824>] (driver_probe_device) from [<c086ee2c>] (__driver_attach+0xdc/0x188)
[ 0.810766] r9:0000011d r8:c144c834 r7:00000000 r6:c15f0a80 r5:c251ba10 r4:00000000
[ 0.810849] [<c086ed50>] (__driver_attach) from [<c086bf60>] (bus_for_each_dev+0x88/0xd4)
[ 0.810985] r7:00000000 r6:c086ed50 r5:c15f0a80 r4:00000000
[ 0.811052] [<c086bed8>] (bus_for_each_dev) from [<c086dad4>] (driver_attach+0x2c/0x30)
[ 0.811182] r6:c15ef1b0 r5:c2c34e80 r4:c15f0a80
[ 0.811243] [<c086daa8>] (driver_attach) from [<c086d2dc>] (bus_add_driver+0x180/0x21c)
[ 0.811364] [<c086d15c>] (bus_add_driver) from [<c086fa6c>] (driver_register+0x84/0x118)
[ 0.811492] r7:00000000 r6:ffffe000 r5:c1428210 r4:c15f0a80
[ 0.811558] [<c086f9e8>] (driver_register) from [<c0871174>] (__platform_driver_register+0x2c/0x34)
[ 0.811683] r5:c1428210 r4:c16524a0
[ 0.811739] [<c0871148>] (__platform_driver_register) from [<c1428234>] (ssbi_driver_init+0x24/0x28)
[ 0.811868] [<c1428210>] (ssbi_driver_init) from [<c0302394>] (do_one_initcall+0x68/0x2c8)
[ 0.811990] [<c030232c>] (do_one_initcall) from [<c140147c>] (kernel_init_freeable+0x1dc/0x23c)
[ 0.812135] r7:cf7b0400 r6:c130339c r5:00000007 r4:c147f6a0
[ 0.812204] [<c14012a0>] (kernel_init_freeable) from [<c0e40e60>] (kernel_init+0x20/0x138)
[ 0.812345] r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:c0e40e40
[ 0.812433] r4:00000000
[ 0.812483] [<c0e40e40>] (kernel_init) from [<c0300150>] (ret_from_fork+0x14/0x24)
[ 0.812596] Exception stack(0xcf70ffb0 to 0xcf70fff8)
[ 0.812684] ffa0: 00000000 00000000 00000000 00000000
[ 0.812809] ffc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[ 0.812923] ffe0: 00000000 00000000 00000000 00000000 00000013 00000000
[ 0.813008] r5:c0e40e40 r4:00000000
[ 0.813075] ---[ end trace ad2443eee078d094 ]---

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: David Heidelberg <david@ixit.cz> # on Nexus 7 (deb)
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20210925234333.2430755-1-dmitry.baryshkov@linaro.org


# 3b0cccef 04-May-2021 Marc Zyngier <maz@kernel.org>

mfd: Bulk conversion to generic_handle_domain_irq()

Wherever possible, replace constructs that match either
generic_handle_irq(irq_find_mapping()) or
generic_handle_irq(irq_linear_revmap()) to a single call to
generic_handle_domain_irq().

Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>


# 7235d9e4 12-Feb-2020 Gustavo A. R. Silva <gustavo@embeddedor.com>

mfd: pm8xxx: Replace zero-length array with flexible-array member

The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
int stuff;
struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>


# 97fb5e8d 29-May-2019 Thomas Gleixner <tglx@linutronix.de>

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>


# 1a25d59a 07-Feb-2019 Brian Masney <masneyb@onstation.org>

mfd: pm8xxx: revert "disassociate old virq if hwirq mapping already exists"

Now that ssbi-gpio is a proper hierarchical IRQ chip, and all in-tree
users of device tree have been updated, we can now drop the hack that
was introduced to disassociate the old Linux virq if a hwirq mapping
already exists. That patch was introduced to not break git bisect for
any existing boards.

This change was tested on an APQ8060 DragonBoard.

Signed-off-by: Brian Masney <masneyb@onstation.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>


# ee08e24c 07-Feb-2019 Brian Masney <masneyb@onstation.org>

mfd: pm8xxx: disassociate old virq if hwirq mapping already exists

Check to see if the hwirq is already associated with another virq on
this IRQ domain. If so, then disassociate it before associating the
hwirq with the new virq.

This is a temporary hack that is needed in order to not break git
bisect for existing boards. The next patch in this series converts
ssbi-gpio to be a hierarchical IRQ chip, then there are several patches
to update all of the device tree files, and finally this patch will be
reverted within the same patch series.

IRQs for ssbi-gpio are all initially setup without an IRQ hierarchy
this driver is probed due to the interrupts property in device tree.
Once ssbi-gpio is converted to be a hierarchical IRQ chip in the next
patch, existing users of gpio[d]_to_irq() will call pmic_gpio_to_irq(),
and that will use the new IRQ chip code in ssbi-gpio that sets up the
IRQ in an IRQ hierarchy. The hwirq is now associated with two Linux
virqs and interrupts will not work as expected. This patch corrects
that issue.

This change was tested on an APQ8060 DragonBoard.

Signed-off-by: Brian Masney <masneyb@onstation.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>


# 3324a7c1 07-Feb-2019 Brian Masney <masneyb@onstation.org>

mfd: pm8xxx: convert to v2 irq interfaces to support hierarchical IRQ chips

Convert the PM8XXX IRQ code to use the version 2 IRQ interface in order
to support hierarchical IRQ chips. This is necessary so that ssbi-gpio
can be setup as a hierarchical IRQ chip with PM8xxx as the parent. IRQ
chips in device tree should be usable from the start without having to
make an additional call to gpio[d]_to_irq() to get the proper IRQ on the
parent.

pm8821_irq_domain_ops and pm8821_irq_domain_map are removed by this
patch since the irq_chip is now contained in the pm_irq_data struct, and
that allows us to use a common IRQ mapping function.

This change was tested on an APQ8060 DragonBoard.

Signed-off-by: Brian Masney <masneyb@onstation.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>


# 0ed2dd03 08-May-2018 Kees Cook <keescook@chromium.org>

treewide: Use struct_size() for devm_kmalloc() and friends

Replaces open-coded struct size calculations with struct_size() for
devm_*, f2fs_*, and sock_* allocations. Automatically generated (and
manually adjusted) from the following Coccinelle script:

// Direct reference to struct field.
@@
identifier alloc =~ "devm_kmalloc|devm_kzalloc|sock_kmalloc|f2fs_kmalloc|f2fs_kzalloc";
expression HANDLE;
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@

- alloc(HANDLE, sizeof(*VAR) + COUNT * sizeof(*VAR->ELEMENT), GFP)
+ alloc(HANDLE, struct_size(VAR, ELEMENT, COUNT), GFP)

// mr = kzalloc(sizeof(*mr) + m * sizeof(mr->map[0]), GFP_KERNEL);
@@
identifier alloc =~ "devm_kmalloc|devm_kzalloc|sock_kmalloc|f2fs_kmalloc|f2fs_kzalloc";
expression HANDLE;
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@

- alloc(HANDLE, sizeof(*VAR) + COUNT * sizeof(VAR->ELEMENT[0]), GFP)
+ alloc(HANDLE, struct_size(VAR, ELEMENT, COUNT), GFP)

// Same pattern, but can't trivially locate the trailing element name,
// or variable name.
@@
identifier alloc =~ "devm_kmalloc|devm_kzalloc|sock_kmalloc|f2fs_kmalloc|f2fs_kzalloc";
expression HANDLE;
expression GFP;
expression SOMETHING, COUNT, ELEMENT;
@@

- alloc(HANDLE, sizeof(SOMETHING) + COUNT * sizeof(ELEMENT), GFP)
+ alloc(HANDLE, CHECKME_struct_size(&SOMETHING, ELEMENT, COUNT), GFP)

Signed-off-by: Kees Cook <keescook@chromium.org>


# 953f432b 14-Nov-2016 Srinivas Kandagatla <srinivas.kandagatla@linaro.org>

mfd: pm8xxx: add support to pm8821

This patch adds support to PM8821 PMIC and interrupt support.
PM8821 is companion device that supplements primary PMIC PM8921 IC.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>


# 40a3a0f2 19-Nov-2016 Linus Walleij <linus.walleij@linaro.org>

mfd: qcom-pm8xxx: Clean up PM8XXX namespace

The Kconfig and file naming for the PM8xxx driver is totally
confusing:

- Kconfig options MFD_PM8XXX and MFD_PM8921_CORE, some in-kernel
users depending on or selecting either at random.
- A driver file named pm8921-core.c even if it is indeed
used by the whole PM8xxx family of chips.
- An irqchip named pm8xxx since it was (I guess) realized that
the driver was generic for all pm8xxx PMICs.

As I may want to add support for PM8901 this is starting to get
really messy. Fix this situation by:

- Remove the MFD_PM8921_CORE symbol and rely solely on MFD_PM8XXX
and convert all users, including LEDs Kconfig and ARM defconfigs
for qcom and multi_v7 to use that single symbol.
- Renaming the driver to qcom-pm8xxx.c to fit along the two
other qcom* prefixed drivers.
- Rename functions withing the driver from 8921 to 8xxx to
indicate it is generic.
- Just drop the =m config from the pxa_defconfig, I have no clue
why it is even there, it is not a Qualcomm platform. (Possibly
older Kconfig noise from saveconfig.)

Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Abhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Andy Gross <andy.gross@linaro.org>
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>