dmaengine: sa11x0: Annotate struct sa11x0_dma_desc with __counted_by

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct sa11x0_dma_desc.
Additionally, since the element count member must be set before accessing
the annotated flexible array member, move its initialization earlier.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Vinod Koul <vkoul@kernel.org>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230817235859.49846-8-keescook@chromium.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: sa11x0-dma: 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() is renamed to .remove().

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

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230919133207.1400430-38-u.kleine-koenig@pengutronix.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: sa11x0: Mark PM functions as __maybe_unused

Without CONFIG_PM_SLEEP, the runtime suspend/resume functions
are unused, producing a warning:

../drivers/dma/sa11x0-dma.c:1042:12: error: 'sa11x0_dma_resume' defined but not used
../drivers/dma/sa11x0-dma.c:1004:12: error: 'sa11x0_dma_suspend' defined but not used

Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Link: https://lore.kernel.org/r/20211026020508.550-1-caihuoqing@baidu.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: sa11x0: Make use of the helper macro SET_NOIRQ_SYSTEM_SLEEP_PM_OPS()

Use the helper macro SET_NOIRQ_SYSTEM_SLEEP_PM_OPS() instead of the
verbose operators ".suspend_noirq /.resume_noirq/.freeze_noirq/
.thaw_noirq/.poweroff_noirq/.restore_noirq", because the
SET_NOIRQ_SYSTEM_SLEEP_PM_OPS() is a nice helper macro that could
be brought in to make code a little clearer, a little more concise.

Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Link: https://lore.kernel.org/r/20210828090117.1814-1-caihuoqing@baidu.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: sa11x0: convert tasklets to use new tasklet_setup() API

In preparation for unconditionally passing the
struct tasklet_struct pointer to all tasklet
callbacks, switch to using the new tasklet_setup()
and from_tasklet() to pass the tasklet pointer explicitly.

Signed-off-by: Romain Perier <romain.perier@gmail.com>
Signed-off-by: Allen Pais <allen.lkml@gmail.com>
Link: https://lore.kernel.org/r/20200831103542.305571-24-allen.lkml@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: sa11x0: 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>
Link: https://lore.kernel.org/r/20200214171435.GA22930@embeddedor
Signed-off-by: Vinod Koul <vkoul@kernel.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 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 as
published by the free software foundation

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

dmaengine: sa11x0: drop useless LIST_HEAD

Drop LIST_HEAD where the variable it declares has never been
used.

The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
identifier x;
@@
- LIST_HEAD(x);
... when != x
// </smpl>

Fixes: 4a533218fccf ("dmaengine: sa11x0: Split device_control")
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: sa11x0: unexport sa11x0_dma_filter_fn and clean up

As we now have no users of sa11x0_dma_filter_fn() in the tree, we can
unexport this function, and remove the now unused header file.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Vinod Koul <vkoul@kernel.org>

treewide: Use struct_size() for kmalloc()-family

One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

struct foo {
int stuff;
void *entry[];
};

instance = kmalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

instance = kmalloc(struct_size(instance, entry, count), GFP_KERNEL);

This patch makes the changes for kmalloc()-family (and kvmalloc()-family)
uses. It was done via automatic conversion with manual review for the
"CHECKME" non-standard cases noted below, using the following Coccinelle
script:

// pkey_cache = kmalloc(sizeof *pkey_cache + tprops->pkey_tbl_len *
// sizeof *pkey_cache->table, GFP_KERNEL);
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@

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

// mr = kzalloc(sizeof(*mr) + m * sizeof(mr->map[0]), GFP_KERNEL);
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@

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

// Same pattern, but can't trivially locate the trailing element name,
// or variable name.
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
expression SOMETHING, COUNT, ELEMENT;
@@

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

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

dmaengine: sa11x0: add DMA filters

Add DMA filters for the sa11x0 DMA channels. This will allow us to
migrate away from directly using the DMA filter function in drivers.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

dmaengine: sa11x0: use correct print specifiers for size_t

This driver when compiled on 64 bits gave warnings:

drivers/dma/sa11x0-dma.c:602:2: warning: format ‘%u’ expects argument of type ‘unsigned int’, but argument 6 has type ‘size_t’ [-Wformat=]

We should use %zu to print 'size_t' values.

Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

dmaengine: sa11x0: use correct print specifiers for u32

This driver when compiled on 64 bits gave warnings:

drivers/dma/sa11x0-dma.c:494:2: warning: format ‘%zx’ expects argument of type ‘size_t’, but argument 4 has type ‘u32’ [-Wformat=]

We should use %x to print 'u32' values.

Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

dmaengine: sa11x0: use correct print specifiers for dma_addr_t

This driver when compiled on 64 bits gave warnings:

drivers/dma/sa11x0-dma.c:466:27: warning: format '%x' expects argument of type 'unsigned int', but argument 4 has type 'dma_addr_t' [-Wformat=]
drivers/dma/sa11x0-dma.c:554:31: warning: format '%x' expects argument of type 'unsigned int', but argument 5 has type 'dma_addr_t' [-Wformat=]
drivers/dma/sa11x0-dma.c:696:34: warning: format '%x' expects argument of type 'unsigned int', but argument 5 has type 'dma_addr_t' [-Wformat=]

We should use %pad to print 'dma_addr_t' values.

Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

dmaengine: sa11x0: report slave capabilities to upper layers

Fix the following warning by initializing necessary fields in the dma_device
structure.

------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at drivers/dma/dmaengine.c:863 dma_async_device_register+0x2b4/0x4f0()
this driver doesn't support generic slave capabilities reporting
Modules linked in:
CPU: 0 PID: 1 Comm: swapper Not tainted 4.0.0-rc5+ #10
Hardware name: Sharp-Collie
[<c0105cd8>] (unwind_backtrace) from [<c0103ef8>] (show_stack+0x10/0x14)
[<c0103ef8>] (show_stack) from [<c010e9b8>] (warn_slowpath_common+0x74/0xac)
[<c010e9b8>] (warn_slowpath_common) from [<c010ea20>] (warn_slowpath_fmt+0x30/0x40)
[<c010ea20>] (warn_slowpath_fmt) from [<c02956fc>] (dma_async_device_register+0x2b4/0x4f0)
[<c02956fc>] (dma_async_device_register) from [<c0296a9c>] (sa11x0_dma_probe+0x21c/0x358)
[<c0296a9c>] (sa11x0_dma_probe) from [<c02c52c0>] (platform_drv_probe+0x30/0x94)
[<c02c52c0>] (platform_drv_probe) from [<c02c39bc>] (driver_probe_device+0x84/0x234)
[<c02c39bc>] (driver_probe_device) from [<c02c3c4c>] (__driver_attach+0x98/0x9c)
[<c02c3c4c>] (__driver_attach) from [<c02c1f9c>] (bus_for_each_dev+0x74/0xa4)
[<c02c1f9c>] (bus_for_each_dev) from [<c02c3230>] (bus_add_driver+0x13c/0x1e8)
[<c02c3230>] (bus_add_driver) from [<c02c4260>] (driver_register+0x78/0xf8)
[<c02c4260>] (driver_register) from [<c0100624>] (do_one_initcall+0x84/0x1f4)
[<c0100624>] (do_one_initcall) from [<c0700e1c>] (kernel_init_freeable+0xf8/0x1b4)
[<c0700e1c>] (kernel_init_freeable) from [<c040a920>] (kernel_init+0x8/0xf0)
[<c040a920>] (kernel_init) from [<c01013a8>] (ret_from_fork+0x14/0x2c)
---[ end trace e188b8fe0e782e75 ]---

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

dmaengine: sa11x0: remove device_alloc_chan_resources handler

Now that device_alloc_chan_resources handler in not mandatory, remove dummy
implementations

Signed-off-by: Vinod Koul <vinod.koul@intel.com>

dmaengine: sa11x0: Fix warning and compilation errors

The sa11x0_dma_resume conflicts between the dmaengine device_resume callback
and the dev_pm_ops resume implementation.

Also remove some unused variables at the same time.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

dmaengine: sa11x0: Split device_control

Split the device_control callback of the SA-11x0 DMA driver to make use of the
newly introduced callbacks, that will eventually be used to retrieve slave
capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

dmaengine: sa11x0: Remove chancnt affectations

chanctnt is already filled by dma_async_device_register, which uses the channel
list to know how much channels there is.

Since it's already filled, we can safely remove it from the drivers' probe
function.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

dma: drop owner assignment from platform_drivers

A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

dmaengine: Remove the context argument to the prep_dma_cyclic operation

The argument is always set to NULL and never used. Remove it.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

dmaengine: sa11x0: remove broken #ifdef

The sa11x0_dma_pm_ops unconditionally reference sa11x0_dma_resume
and sa11x0_dma_suspend, which currently breaks if CONFIG_PM_SLEEP
is disabled.

There is probably a better way to remove the reference in this
case, but the safe choice is to have the suspend/resume code always
built in the driver.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: dmaengine@vger.kernel.org
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

dmaengine: sa11x0: use DMA_COMPLETE for dma completion status

Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Drivers: dma: remove __dev* attributes.

CONFIG_HOTPLUG is going away as an option. As a result, the __dev*
markings need to be removed.

This change removes the use of __devinit, __devexit_p, __devinitconst,
and __devexit from these drivers.

Based on patches originally written by Bill Pemberton, but redone by me
in order to handle some of the coding style issues better, by hand.

Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Viresh Kumar <viresh.linux@gmail.com>
Cc: Dan Williams <djbw@fb.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Barry Song <baohua.song@csr.com>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Jassi Brar <jassisinghbrar@gmail.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

dma: remove use of __devinit

CONFIG_HOTPLUG is going away as an option so __devinit is no longer
needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Li Yang <leoli@freescale.com>
Cc: Zhang Wei <zw@zh-kernel.org>
Cc: Barry Song <baohua.song@csr.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

dma: remove use of __devexit_p

CONFIG_HOTPLUG is going away as an option so __devexit_p is no longer
needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Barry Song <baohua.song@csr.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

dmaengine: Pass flags via device_prep_dma_cyclic() callback

Change the parameter list of device_prep_dma_cyclic() so the DMA drivers
can receive the flags coming from clients.
This feature can be used during audio operation to disable all audio
related interrupts when the DMA_PREP_INTERRUPT is cleared from the flags.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Vinod Koul <vinod.koul@linux.intel.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

dmaengine: sa11x0-dma: add cyclic DMA support

Add support for cyclic DMA on sa11x0 platforms. This follows the
discussed behaviour that the callback will be called at some point
after period expires, and may coalesce multiple period expiries into
one callback (due to the tasklet behaviour.)

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

dmaengine: sa11x0-dma: fix DMA residue support

The semantics now implemented are:

- If the cookie has completed successfully, the residue will be zero.
- If the cookie is in progress or the channel is paused, it will be the
number of bytes yet to be transferred. [*]
- If the cookie is queued, it will be the number of bytes in the
descriptor.

* - where this is the number of bytes yet to be transferred to/from
RAM.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

dmaengine: split out virtual channel DMA support from sa11x0 driver

Split the virtual slave channel DMA support from the sa11x0 driver so
this code can be shared with other slave DMA engine drivers.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: sa11x0: fix build errors from DMA engine API updates

The recent merge of the sa11x0 code into mainline had silent conflicts
with further development of the DMA engine API, leading to build errors
and warnings:

drivers/net/irda/sa1100_ir.c: In function 'sa1100_irda_dma_start':
drivers/net/irda/sa1100_ir.c:151: error: too few arguments to function 'chan->device->device_prep_slave_sg'
drivers/dma/sa11x0-dma.c: In function 'sa11x0_dma_probe':
drivers/dma/sa11x0-dma.c:950: warning: assignment from incompatible pointer type

Fix these.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

DMA: sa11x0: add SA-11x0 DMA driver

Add support for the SA-11x0 DMA driver, which replaces the private
API version in arch/arm/mach-sa1100/dma.c.

We model this as a set of virtual DMA channels, one for each request
signal, and assign the virtual DMA channel to a physical DMA channel
when there is work to be done. This allows DMA users to claim their
channels, and hold them while not in use, without affecting the
availability of the physical channels.

Another advantage over this approach, compared to the private version,
is that a channel can be reconfigured on the fly without having to
release and re-request it - which for the IrDA driver, allows us to
use DMA for SIR mode transmit without eating up three physical
channels. As IrDA is half-duplex, we actually only need one physical
channel, and this architecture allows us to achieve that.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>