mmc: bcm2835: 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 (mostly) ignored
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.

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

Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://lore.kernel.org/r/20230727070051.17778-2-frank.li@vivo.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: fix deferred probing

The driver overrides the error codes and IRQ0 returned by platform_get_irq()
to -EINVAL, so if it returns -EPROBE_DEFER, the driver will fail the probe
permanently instead of the deferred probing. Switch to propagating the error
codes upstream. Since commit ce753ad1549c ("platform: finally disallow IRQ0
in platform_get_irq() and its ilk") IRQ0 is no longer returned by those APIs,
so we now can safely ignore it...

Fixes: 660fc733bd74 ("mmc: bcm2835: Add new driver for the sdhost controller.")
Cc: stable@vger.kernel.org # v5.19+
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Link: https://lore.kernel.org/r/20230617203622.6812-2-s.shtylyov@omp.ru
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Replace kmap_atomic() with kmap_local_page()

kmap_local_page() is equivalent to kmap_atomic() except that it does not
disable page faults or preemption. Where possible kmap_local_page() is
preferred to kmap_atomic() - refer kernel highmem documentation.

In this case, there is no need to disable page faults or preemption, so
replace kmap_atomic() with kmap_local_page(), and, correspondingly,
kunmap_atomic() with kunmap_local().

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20221005101951.3165-7-adrian.hunter@intel.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Remove local_irq_{save,restore}() around sg_miter_{next,stop}()

sg_miter_next() using an sg_mapping_iter with flag SG_MITER_ATOMIC uses
kmap_atomic() to map pages.

A long time ago the kmap_atomic API required a slot to be provided which
risked the possibility that other code might use the same slot at the
same time. Disabling interrupts prevented the possibility of an interrupt
handler doing that. However, that went away with
commit 3e4d3af501cc ("mm: stack based kmap_atomic()").

Remove local_irq_{save,restore}() around sg_miter_{next,stop}().

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20221005101951.3165-6-adrian.hunter@intel.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Remove local_irq_{save,restore}() around k[un]map_atomic()

A long time ago the kmap_atomic API required a slot to be provided which
risked the possibility that other code might use the same slot at the
same time. Disabling interrupts prevented the possibility of an interrupt
handler doing that. However, that went away with
commit 3e4d3af501cc ("mm: stack based kmap_atomic()").

Unfortunately, that unnecessary pattern of code has been copied since
and persists in bcm2385.c.

Remove it.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20221005101951.3165-5-adrian.hunter@intel.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: improve API to make clear hw_reset callback is for cards

To make it unambiguous that the hw_reset callback is for cards and not
for controllers, we add 'card' to the callback name and convert all
users in one go. We keep the argument as mmc_host, though, because the
callback is used very early when mmc_card is not yet populated.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20220408080045.6497-4-wsa+renesas@sang-engineering.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: stop setting chan_config->slave_id

The field is not interpreted by the DMA engine driver, as all the data
is passed from devicetree instead. Remove the assignment so the field
can eventually be deleted.

Reviewed-by: Nicolas Saenz Julienne <nsaenz@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20211122222203.4103644-5-arnd@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>

mmc: Set PROBE_PREFER_ASYNCHRONOUS for drivers that existed in v4.14

This is like commit 3d3451124f3d ("mmc: sdhci-msm: Prefer asynchronous
probe") but applied to a whole pile of drivers. This batch converts
the drivers that appeared to be around in the v4.14 timeframe.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com> # SDHI drivers
Link: https://lore.kernel.org/r/20200903162412.3.Id1ff21470f08f427aedd0a6535dcd83ccc56b278@changeid
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Simplify with dev_err_probe()

Common pattern of handling deferred probe can be simplified with
dev_err_probe(). Less code and the error value gets printed.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20200902193658.20539-2-krzk@kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: host: Drop redundant MMC_CAP_ERASE

The MMC_CAP_ERASE bit is no longer used by the mmc core as erase, discard
and trim operations are now always supported. Therefore, drop the bit and
move all mmc hosts away from using it.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Rui Miguel Silva <rmfrfs@gmail.com>
Link: https://lore.kernel.org/r/20200508112902.23575-1-ulf.hansson@linaro.org
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

mmc: bcm2835: Use dma_request_chan() instead dma_request_slave_channel()

dma_request_slave_channel() is a wrapper on top of dma_request_chan()
eating up the error code.

By using dma_request_chan() directly the driver can support deferred
probing against DMA.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Link: https://lore.kernel.org/r/20191217122254.7103-1-peter.ujfalusi@ti.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Use devm_platform_ioremap_resource wrapper

Use devm_platform_ioremap_resource helper which wraps
platform_get_resource() and devm_ioremap_resource() together.

Generated by: scripts/coccinelle/api/devm_platform_ioremap_resource.cocci.

More information about semantic patching is available at
http://coccinelle.lip6.fr/

Signed-off-by: Saiyam Doshi <saiyamdoshi.in@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Take SWIOTLB memory size limitation into account

Make sure the sdhost driver doesn't use requests bigger than SWIOTLB
can handle.

Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: 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: Ulf Hansson <ulf.hansson@linaro.org>
Cc: linux-mmc@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Revert "mmc: bcm2835: Terminate timeout work synchronously"

The commit 37fefadee8bb ("mmc: bcm2835: Terminate timeout work
synchronously") causes lockups in case of hardware timeouts due the
timeout work also calling cancel_delayed_work_sync() on its own.
So revert it.

Fixes: 37fefadee8bb ("mmc: bcm2835: Terminate timeout work synchronously")
Cc: stable@vger.kernel.org
Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Deduplicate reset of driver data on remove

The BCM2835 MMC host driver sets the device's driver data pointer to
NULL on ->remove() even though the driver core subsequently does the
same in __device_release_driver(). Drop the duplicate assignment.

Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Drop pointer to mmc_host from bcm2835_host

The BCM2835 MMC host driver uses a pointer to get from the private
bcm2835_host structure to the generic mmc_host structure. However the
latter is always immediately preceding the former in memory, so compute
its address with a subtraction (which is cheaper than a dereference) and
drop the superfluous pointer.

No functional change intended.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Alexander Graf <agraf@suse.de>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Drop DMA channel error pointer check

bcm2835_add_host() invokes IS_ERR_OR_NULL() on a DMA channel pointer,
however dma_request_slave_channel() (which was used to populate the
pointer) never returns an error pointer. So a NULL pointer check is
sufficient.

Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Fix DMA channel leak on probe error

The BCM2835 MMC host driver requests a DMA channel on probe but neglects
to release the channel in the probe error path. The channel may
therefore be leaked, in particular if devm_clk_get() causes probe
deferral. Fix it.

Fixes: 660fc733bd74 ("mmc: bcm2835: Add new driver for the sdhost controller.")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v4.12+
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Properly handle dmaengine_prep_slave_sg

In case dmaengine_prep_slave_sg fails we need to call dma_unmap_sg.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Refactor dma_map_sg handling

There are two variables len within bcm2835_prepare_dma. So rename the
result of dma_map_sg to sg_len. While we are at this add a bail out to
simplify the following change.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Terminate timeout work synchronously

It's better to make sure that the timeout work is really terminated
before calling mmc_request_done.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Avoid possible races on data requests

There are two accesses on the data requests which are not protected by
the mutex. So fix this accordingly.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Release DMA channel on driver unload

We need to release the slave DMA channel during driver unload.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Recover from MMC_SEND_EXT_CSD

If the user issues an "mmc extcsd read", the SD controller receives
what it thinks is a SEND_IF_COND command with an unexpected data block.
The resulting operations leave the FSM stuck in READWAIT, a state which
persists until the MMC framework resets the controller, by which point
the root filesystem is likely to have been unmounted.

A less heavyweight solution is to detect the condition and nudge the
FSM by asserting the (self-clearing) FORCE_DATA_MODE bit.

Link: https://github.com/raspberrypi/linux/issues/2728
Signed-off-by: Phil Elwell <phil@raspberrypi.org>
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: reset host on timeout

The bcm2835 mmc host tends to lock up for unknown reason so reset it on
timeout. The upper mmc block layer tries retransimitting with single
blocks which tends to work out after a long wait.

This is better than giving up and leaving the machine broken for no
obvious reason.

Fixes: 660fc733bd74 ("mmc: bcm2835: Add new driver for the sdhost controller.")
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Switch to SPDX identifier

Adopt the SPDX license identifier headers to ease license compliance
management.

Cc: Phil Elwell <phil@raspberrypi.org>
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Don't overwrite max frequency unconditionally

The optional DT parameter max-frequency could init the max bus frequency.
So take care of this, before setting the max bus frequency.

Fixes: 660fc733bd74 ("mmc: bcm2835: Add new driver for the sdhost controller.")
Signed-off-by: Phil Elwell <phil@raspberrypi.org>
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Cc: <stable@vger.kernel.org> # 4.12+
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: constify mmc_host_ops structures

The mmc_host_ops structure is only stored in the ops field of an
mmc_host structure, which is declared as const. Thus the mmc_host_ops
structure itself can be const.

Done with the help of Coccinelle.

// <smpl>
@r disable optional_qualifier@
identifier i;
position p;
@@
static struct mmc_host_ops i@p = { ... };

@ok1@
struct mmc_host *mmc;
identifier r.i;
position p;
@@
mmc->ops = &i@p

@bad@
position p != {r.p,ok1.p};
identifier r.i;
struct mmc_host_ops e;
@@
e@i@p

@depends on !bad disable optional_qualifier@
identifier r.i;
@@
static
+const
struct mmc_host_ops i = { ... };
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: fix potential null pointer dereferences

Null check at line 1165: if (mrq->cmd), implies that mrq->cmd might
be NULL.
Add null checks before dereferencing pointer mrq->cmd in order to avoid
any potential NULL pointer dereference.

Addresses-Coverity-ID: 1408740
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Fix possible NULL ptr dereference in bcm2835_request

This fixes a NULL pointer dereference in case of a MMC request with a
set block count command and no data.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Tested-by: Peter Robinson <pbrobinson@gmail.com>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

mmc: bcm2835: Add new driver for the sdhost controller.

The 2835 has two SD controllers: The Arasan sdhci controller (supported
by the iproc driver) and a custom sdhost controller. This patch adds a
driver for the latter.

The sdhci controller supports both sdcard and sdio. The sdhost
controller supports the sdcard only, but has better performance. Also
note that the rpi3 has sdio wifi, so driving the sdcard with the sdhost
controller allows to use the sdhci controller for wifi support.

The configuration is done by devicetree via pin muxing. Both SD
controller are available on the same pins (2 pin groups = pin 22 to 27 +
pin 48 to 53). So it's possible to use both SD controllers at the same
time with different pin groups.

The code was originally written by Phil Elwell in the downstream
Rasbperry Pi tree. In preparation for the upstream merge it was
cleaned up and the code base was moderized by Eric Anholt, Stefan
Wahren and Gerd Hoffmann.

Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>