dmaengine: sun4i-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>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://lore.kernel.org/r/20230919133207.1400430-46-u.kleine-koenig@pengutronix.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: drivers: Use devm_platform_ioremap_resource()

platform_get_resource() and devm_ioremap_resource() are wrapped up in the
devm_platform_ioremap_resource() helper. Use the helper and get rid of the
local variable for struct resource *. We now have a function call less.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Link: https://lore.kernel.org/r/20221110152528.7821-1-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: sun4i: Set the maximum segment size

The sun4i DMA engine supports transfer sizes up to 128k for normal DMA
and 16M for dedicated DMA, as documented in the A10 and A20 manuals.

Since this is larger than the default segment size limit (64k), exposing
the real limit reduces the number of transfers needed for a transaction.
However, because the device can only report one segment size limit, we
have to expose the smaller limit from normal DMA.

One complication is that the driver combines pairs of periodic transfers
to reduce programming overhead. This only works when the period size is
at most half of the maximum transfer size. With the default 64k segment
size limit, this was always the case, but for normal DMA it is no longer
guaranteed. Skip the optimization if the period is too long; even
without it, the overhead is less than before.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Link: https://lore.kernel.org/r/20220621031350.36187-1-samuel@sholland.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: sun4i: Use list_move_tail instead of list_del/list_add_tail

Using list_move_tail() instead of list_del() + list_add_tail().

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Acked-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/1623036035-30614-1-git-send-email-zou_wei@huawei.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: sun4i-dma: Demote obvious misuse of kerneldoc to standard comment blocks

No attempt has been made to document any of the demoted functions here.

Fixes the following W=1 kernel build warning(s):

drivers/dma/sun4i-dma.c:321: warning: Function parameter or member 'priv' not described in '__execute_vchan_pending'
drivers/dma/sun4i-dma.c:321: warning: Function parameter or member 'vchan' not described in '__execute_vchan_pending'
drivers/dma/sun4i-dma.c:435: warning: Function parameter or member 'chan' not described in 'generate_ndma_promise'
drivers/dma/sun4i-dma.c:435: warning: Function parameter or member 'src' not described in 'generate_ndma_promise'
drivers/dma/sun4i-dma.c:435: warning: Function parameter or member 'dest' not described in 'generate_ndma_promise'
drivers/dma/sun4i-dma.c:435: warning: Function parameter or member 'len' not described in 'generate_ndma_promise'
drivers/dma/sun4i-dma.c:435: warning: Function parameter or member 'sconfig' not described in 'generate_ndma_promise'
drivers/dma/sun4i-dma.c:435: warning: Function parameter or member 'direction' not described in 'generate_ndma_promise'
drivers/dma/sun4i-dma.c:501: warning: Function parameter or member 'chan' not described in 'generate_ddma_promise'
drivers/dma/sun4i-dma.c:501: warning: Function parameter or member 'src' not described in 'generate_ddma_promise'
drivers/dma/sun4i-dma.c:501: warning: Function parameter or member 'dest' not described in 'generate_ddma_promise'
drivers/dma/sun4i-dma.c:501: warning: Function parameter or member 'len' not described in 'generate_ddma_promise'
drivers/dma/sun4i-dma.c:501: warning: Function parameter or member 'sconfig' not described in 'generate_ddma_promise'
drivers/dma/sun4i-dma.c:577: warning: Function parameter or member 'contract' not described in 'get_next_cyclic_promise'
drivers/dma/sun4i-dma.c:596: warning: Function parameter or member 'vd' not described in 'sun4i_dma_free_contract'

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: "Emilio López" <emilio@elopez.com.ar>
Link: https://lore.kernel.org/r/20200714111546.1755231-10-lee.jones@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: sun4i: set the linear_mode properly

Commit 6ebb827f7aad ("dmaengine: sun4i: use 'linear_mode' in
sun4i_dma_prep_dma_cyclic") updated the condition but introduced a semi
colon this making this statement have no effect, so add the bitwise OR
to fix it"

Fixes: 6ebb827f7aad ("dmaengine: sun4i: use 'linear_mode' in sun4i_dma_prep_dma_cyclic")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lore.kernel.org/r/20200214044609.2215861-1-vkoul@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: sun4i: use 'linear_mode' in sun4i_dma_prep_dma_cyclic

drivers/dma/sun4i-dma.c: In function sun4i_dma_prep_dma_cyclic:
drivers/dma/sun4i-dma.c:672:24: warning:
variable linear_mode set but not used [-Wunused-but-set-variable]

commit ffc079a4accc ("dmaengine: sun4i: Add support for cyclic requests with dedicated DMA")
involved this, explicitly using the value makes the code more readable.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20200207024445.44600-1-yuehaibing@huawei.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: sun4i: Add support for cyclic requests with dedicated DMA

Currently the cyclic transfers can be used only with normal DMAs. They
can be used by pcm_dmaengine module, which is required for implementing
sound with sun4i-hdmi encoder. This is so because the controller can
accept audio only from a dedicated DMA.

This patch enables them, following the existing style for the
scatter/gather type transfers.

Signed-off-by: Stefan Mavrodiev <stefan@olimex.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200110141140.28527-2-stefan@olimex.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: virt-dma: Add missing locking

Originally freeing descriptors was split into a locked and an unlocked
part. The locked part in vchan_get_all_descriptors() collected all
descriptors on a separate list_head. This was done to allow iterating
over that new list in vchan_dma_desc_free_list() without a lock held.

This became broken in 13bb26ae8850 ("dmaengine: virt-dma: don't always
free descriptor upon completion"). With this commit
vchan_dma_desc_free_list() no longer exclusively operates on the
separate list, but starts to put descriptors which can be reused back on
&vc->desc_allocated. This list operation should have been locked, but
wasn't.
In the mean time drivers started to call vchan_dma_desc_free_list() with
their lock held so that we now have the situation that
vchan_dma_desc_free_list() is called locked from some drivers and
unlocked from others.
To clean this up we have to do two things:

1. Add missing locking in vchan_dma_desc_free_list()
2. Make sure drivers call vchan_dma_desc_free_list() unlocked

This needs to be done atomically, so in this patch the locking is added
and all drivers are fixed.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Green Wan <green.wan@sifive.com>
Tested-by: Green Wan <green.wan@sifive.com>
Link: https://lore.kernel.org/r/20191216105328.15198-3-s.hauer@pengutronix.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: Remove dev_err() usage after platform_get_irq()

We don't need dev_err() messages when platform_get_irq() fails now that
platform_get_irq() prints an error message itself when something goes
wrong. Let's remove these prints with a simple semantic patch.

// <smpl>
@@
expression ret;
struct platform_device *E;
@@

ret =
(
platform_get_irq(E, ...)
|
platform_get_irq_byname(E, ...)
);

if ( \( ret < 0 \| ret <= 0 \) )
{
(
-if (ret != -EPROBE_DEFER)
-{ ...
-dev_err(...);
-... }
|
...
-dev_err(...);
)
...
}
// </smpl>

While we're here, remove braces on if statements that only have one
statement (manually).

Cc: Vinod Koul <vkoul@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: dmaengine@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20190730181557.90391-11-swboyd@chromium.org
Signed-off-by: Vinod Koul <vkoul@kernel.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>

dmaengine: sun4i: fix invalid argument

The "pchans_used" field is an unsigned long array.

for_each_clear_bit_from() expects an unsigned long pointer,
not an array address.

$ make C=2 drivers/dma/sun4i-dma.o
CHECK drivers/dma/sun4i-dma.c
drivers/dma/sun4i-dma.c:241:9: warning: incorrect type in argument 1 (different base types)
drivers/dma/sun4i-dma.c:241:9: expected unsigned long const *p
drivers/dma/sun4i-dma.c:241:9: got unsigned long ( *<noident> )[1]

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

remove lots of IS_ERR_VALUE abuses

Most users of IS_ERR_VALUE() in the kernel are wrong, as they
pass an 'int' into a function that takes an 'unsigned long'
argument. This happens to work because the type is sign-extended
on 64-bit architectures before it gets converted into an
unsigned type.

However, anything that passes an 'unsigned short' or 'unsigned int'
argument into IS_ERR_VALUE() is guaranteed to be broken, as are
8-bit integers and types that are wider than 'unsigned long'.

Andrzej Hajda has already fixed a lot of the worst abusers that
were causing actual bugs, but it would be nice to prevent any
users that are not passing 'unsigned long' arguments.

This patch changes all users of IS_ERR_VALUE() that I could find
on 32-bit ARM randconfig builds and x86 allmodconfig. For the
moment, this doesn't change the definition of IS_ERR_VALUE()
because there are probably still architecture specific users
elsewhere.

Almost all the warnings I got are for files that are better off
using 'if (err)' or 'if (err < 0)'.
The only legitimate user I could find that we get a warning for
is the (32-bit only) freescale fman driver, so I did not remove
the IS_ERR_VALUE() there but changed the type to 'unsigned long'.
For 9pfs, I just worked around one user whose calling conventions
are so obscure that I did not dare change the behavior.

I was using this definition for testing:

#define IS_ERR_VALUE(x) ((unsigned long*)NULL == (typeof (x)*)NULL && \
unlikely((unsigned long long)(x) >= (unsigned long long)(typeof(x))-MAX_ERRNO))

which ends up making all 16-bit or wider types work correctly with
the most plausible interpretation of what IS_ERR_VALUE() was supposed
to return according to its users, but also causes a compile-time
warning for any users that do not pass an 'unsigned long' argument.

I suggested this approach earlier this year, but back then we ended
up deciding to just fix the users that are obviously broken. After
the initial warning that caused me to get involved in the discussion
(fs/gfs2/dir.c) showed up again in the mainline kernel, Linus
asked me to send the whole thing again.

[ Updated the 9p parts as per Al Viro - Linus ]

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lkml.org/lkml/2016/1/7/363
Link: https://lkml.org/lkml/2016/5/27/486
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> # For nvmem part
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

dmaengine: sun4i: support module autoloading

MODULE_DEVICE_TABLE() is missing, so the module isn't auto-loading on
supported systems. This commit adds the missing line so it loads
automatically when building it as a module and running on a system
with the early sunxi DMA engine.

Signed-off-by: Emilio López <emilio.lopez@collabora.co.uk>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

dmaengine: sun4i: fix unsafe list iteration

Currently, sun4i_dma_free_contract iterates over lists and frees memory
as it goes through them, causing reads to recently freed memory to
be performed. Fix this by using the safe version of the iterator, so
freed memory is not referenced at all.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Emilio López <emilio@elopez.com.ar>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

dmaengine: sun4i: Add support for the DMA engine on sun[457]i SoCs

This patch adds support for the DMA engine present on Allwinner A10,
A13, A10S and A20 SoCs. This engine has two kinds of channels: normal
and dedicated. The main difference is in the mode of operation;
while a single normal channel may be operating at any given time,
dedicated channels may operate simultaneously provided there is no
overlap of source or destination.

Hardware documentation can be found on A10 User Manual (section 12), A13
User Manual (section 14) and A20 User Manual (section 1.12)

Signed-off-by: Emilio López <emilio@elopez.com.ar>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>