linux-toradex.git/drivers/ata/pata_falcon.c, branch v6.10

ata: pata_falcon: Convert to platform remove callback returning void

2023-11-08T00:00:44+00:00

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.

Signed-off-by: Uwe Kleine-König 
Reviewed-by: Sergey Shtylyov 
Reviewed-by: Niklas Cassel 
Signed-off-by: Damien Le Moal

ata: pata_falcon: Stop using module_platform_driver_probe()

2023-11-08T00:00:03+00:00

On today's platforms the benefit of platform_driver_probe() isn't that
relevant any more. It allows to drop some code after booting (or module
loading) for .probe() and discard the .remove() function completely if
the driver is built-in. This typically saves a few 100k.

The downside of platform_driver_probe() is that the driver cannot be
bound and unbound at runtime which is ancient and so slightly
complicates testing. There are also thoughts to deprecate
platform_driver_probe() because it adds some complexity in the driver
core for little gain. Also many drivers don't use it correctly. This
driver for example misses to mark the driver struct with __ref which is
needed to suppress a (W=1) modpost warning.

Signed-off-by: Uwe Kleine-König 
Reviewed-by: Sergey Shtylyov 
Reviewed-by: Niklas Cassel 
Signed-off-by: Damien Le Moal

ata: pata_falcon: add data_swab option to byte-swap disk data

2023-08-28T10:14:41+00:00

Some users of pata_falcon on Q40 have IDE disks in default
IDE little endian byte order, whereas legacy disks use
host-native big-endian byte order as on the Atari Falcon.

Add module parameter 'data_swab' to allow connecting drives
with non-native data byte order. Drives selected by the
data_swap bit mask will have their user data byte-swapped to
host byte order, i.e. 'pata_falcon.data_swab=2' will byte-swap
all user data on drive B, leaving data on drive A in native
byte order. On Q40, drives on a second IDE interface may be
added to the bit mask as bits 2 and 3.

Default setting is no byte swapping, i.e. compatibility with
the native Falcon or Q40 operating system disk format.

Cc: William R Sowerbutts 
Cc: Finn Thain 
Cc: Geert Uytterhoeven 
Tested-by: William R Sowerbutts 
Signed-off-by: Michael Schmitz 
Reviewed-by: Sergey Shtylyov 
Reviewed-by: Geert Uytterhoeven 
Signed-off-by: Damien Le Moal

ata: pata_falcon: fix IO base selection for Q40

2023-08-28T10:14:39+00:00

With commit 44b1fbc0f5f3 ("m68k/q40: Replace q40ide driver
with pata_falcon and falconide"), the Q40 IDE driver was
replaced by pata_falcon.c.

Both IO and memory resources were defined for the Q40 IDE
platform device, but definition of the IDE register addresses
was modeled after the Falcon case, both in use of the memory
resources and in including register shift and byte vs. word
offset in the address.

This was correct for the Falcon case, which does not apply
any address translation to the register addresses. In the
Q40 case, all of device base address, byte access offset
and register shift is included in the platform specific
ISA access translation (in asm/mm_io.h).

As a consequence, such address translation gets applied
twice, and register addresses are mangled.

Use the device base address from the platform IO resource
for Q40 (the IO address translation will then add the correct
ISA window base address and byte access offset), with register
shift 1. Use MMIO base address and register shift 2 as before
for Falcon.

Encode PIO_OFFSET into IO port addresses for all registers
for Q40 except the data transfer register. Encode the MMIO
offset there (pata_falcon_data_xfer() directly uses raw IO
with no address translation).

Reported-by: William R Sowerbutts 
Closes: https://lore.kernel.org/r/CAMuHMdUU62jjunJh9cqSqHT87B0H0A4udOOPs=WN7WZKpcagVA@mail.gmail.com
Link: https://lore.kernel.org/r/CAMuHMdUU62jjunJh9cqSqHT87B0H0A4udOOPs=WN7WZKpcagVA@mail.gmail.com
Fixes: 44b1fbc0f5f3 ("m68k/q40: Replace q40ide driver with pata_falcon and falconide")
Cc: stable@vger.kernel.org
Cc: Finn Thain 
Cc: Geert Uytterhoeven 
Tested-by: William R Sowerbutts 
Signed-off-by: Michael Schmitz 
Reviewed-by: Sergey Shtylyov 
Reviewed-by: Geert Uytterhoeven 
Signed-off-by: Damien Le Moal

ata: pata_falcon: Remove #include

2023-08-23T23:09:59+00:00

The Atari Falcon PATA driver does not need anything from .

Signed-off-by: Geert Uytterhoeven 
Reviewed-by: Sergey Shtylyov 
Signed-off-by: Damien Le Moal

scsi: ata: Declare SCSI host templates const

2023-03-24T23:19:19+00:00

Make it explicit that ATA host templates are not modified.

Reviewed-by: Linus Walleij 
Acked-by: Damien Le Moal 
Reviewed-by: Serge Semin  (for DWC AHCI SATA)
Reviewed-by: John Garry 
Reviewed-by: Jon Hunter  (for Tegra)
Cc: Christoph Hellwig 
Cc: Ming Lei 
Cc: Hannes Reinecke 
Cc: John Garry 
Cc: Mike Christie 
Signed-off-by: Bart Van Assche 
Link: https://lore.kernel.org/r/20230322195515.1267197-5-bvanassche@acm.org
Signed-off-by: Martin K. Petersen

pata_falcon: Avoid type warnings from sparse

2021-11-29T11:28:13+00:00

The zero day bot reported some sparse complaints in pata_falcon.c. E.g.

drivers/ata/pata_falcon.c:58:41: warning: cast removes address space '__iomem' of expression
drivers/ata/pata_falcon.c:58:41: warning: incorrect type in argument 1 (different address spaces)
drivers/ata/pata_falcon.c:58:41:    expected unsigned short volatile [noderef] [usertype] __iomem *port
drivers/ata/pata_falcon.c:58:41:    got unsigned short [usertype] *

The same thing shows up in 8 places, all told. Avoid this by removing
unnecessary type casts.

Cc: Jens Axboe 
Cc: Michael Schmitz 
Cc: Geert Uytterhoeven 
Reported-by: kernel test robot 
Suggested-by: Geert Uytterhoeven 
Signed-off-by: Finn Thain 
Reviewed-by: Geert Uytterhoeven 
Signed-off-by: Damien Le Moal

scsi: ata: Use scsi_cmd_to_rq() instead of scsi_cmnd.request

2021-08-12T02:25:37+00:00

Prepare for removal of the request pointer by using scsi_cmd_to_rq()
instead. This patch does not change any functionality.

Link: https://lore.kernel.org/r/20210809230355.8186-8-bvanassche@acm.org
Cc: Jens Axboe 
Cc: Christoph Hellwig 
Cc: Hannes Reinecke 
Cc: Ming Lei 
Reviewed-by: Hannes Reinecke 
Signed-off-by: Bart Van Assche 
Signed-off-by: Martin K. Petersen

m68k/q40: Replace q40ide driver with pata_falcon and falconide

2021-06-10T22:30:12+00:00

This allows m68k q40 systems to switch from the deprecated IDE subsystem
to libata.

Enhance the byte-swapping falconide and pata_falcon platform drivers to
accept an irq resource, for use on q40. Atari ST-DMA IRQ arrangements seem
to co-exist with q40 IRQ arrangements without too much mess.

The new IO resources were added solely for the purpose of making
request_region() reservations identical to those made by q40ide: these
regions aren't used for actual IO.

Cc: Michael Schmitz 
Cc: Richard Zidlicky 
Reviewed-and-tested-by: Michael Schmitz 
Acked-by: Geert Uytterhoeven 
Signed-off-by: Finn Thain 
Link: https://lore.kernel.org/r/eefb7e9c2291e09fb4e065ce06bc105f05bb9e06.1623287706.git.fthain@linux-m68k.org
Signed-off-by: Jens Axboe

m68k/atari: Convert Falcon IDE drivers to platform drivers

2019-11-18T09:18:59+00:00

Autoloading of Falcon IDE driver modules requires converting these
drivers to platform drivers.

Add platform device for Falcon IDE interface in Atari platform setup
code. Use this in the pata_falcon driver in place of the simple
platform device set up on the fly.

Convert falconide driver to use the same platform device that is used
by pata_falcon also. (With the introduction of a platform device for
the Atari Falcon IDE interface, the old Falcon IDE driver no longer
loads (resource already claimed by the platform device)).

Tested (as built-in driver) on my Atari Falcon.

Signed-off-by: Michael Schmitz 
Acked-by: Bartlomiej Zolnierkiewicz 
Link: https://lore.kernel.org/r/1573008449-8226-1-git-send-email-schmitzmic@gmail.com
Signed-off-by: Geert Uytterhoeven