18 Commits

Author SHA1 Message Date
Nathan Chancellor
195c316786 power: reset: at91: Drop '__init' from at91_wakeup_status()
When building with clang, there are two section mismatch warnings:

  WARNING: modpost: vmlinux: section mismatch in reference: at91_poweroff_probe+0x7c (section: .text) -> at91_wakeup_status (section: .init.text)
  WARNING: modpost: vmlinux: section mismatch in reference: at91_shdwc_probe+0xcc (section: .text) -> at91_wakeup_status (section: .init.text)

Drop '__init' from at91_wakeup_status() to clear up the mismatch.

Fixes: dde74a5de817 ("power: reset: at91-sama5d2_shdwc: Stop using module_platform_driver_probe()")
Fixes: 099806de68b7 ("power: reset: at91-poweroff: Stop using module_platform_driver_probe()")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
2023-12-24 23:43:10 +01:00
Uwe Kleine-König
a31438ece3 power: reset: at91-poweroff: 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.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Claudiu Beznea <claudiu.beznea@tuxon.dev>
Link: https://lore.kernel.org/r/20231104211501.3676352-21-u.kleine-koenig@pengutronix.de
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
2023-11-15 23:15:38 +01:00
Uwe Kleine-König
099806de68 power: reset: at91-poweroff: Stop using module_platform_driver_probe()
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 <u.kleine-koenig@pengutronix.de>
Reviewed-by: Claudiu Beznea <claudiu.beznea@tuxon.dev>
Link: https://lore.kernel.org/r/20231104211501.3676352-17-u.kleine-koenig@pengutronix.de
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
2023-11-15 23:15:37 +01:00
Yangtao Li
0b64a0e53c power: reset: at91-poweroff: Convert to devm_platform_ioremap_resource()
Use devm_platform_ioremap_resource() to simplify code.

Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
2023-07-19 23:28:58 +02:00
Claudiu Beznea
caa6e150f8 power: reset: at91-poweroff: move shdwc related data to one structure
Move SHDWC realted data to only one structure to have them grouped.
Inspired from commit 9be74f0d39c1 ("power: reset: at91-poweroff: make
mpddrc_base part of struct shdwc").

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
2018-12-06 21:56:37 +01:00
Claudiu.Beznea@microchip.com
e6ae9a05a4 power: reset: at91-poweroff: remove at91_ramc_of_match
Remove at91_ramc_of_match[] since it is not used anywhere in this code.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
2018-12-05 23:29:57 +01:00
Claudiu.Beznea@microchip.com
996463fdb8 power: reset: at91-poweroff: use one poweroff function for at91-poweroff
Use only one poweroff function and adapt it to work for both scenarios
(with LPDDR or not). The assignement of pm_power_off was moved at the
end of probe after all initializations are OK. This patch adapt the idea
from commit 4e018c1e9b05 ("power: reset: at91-poweroff: use only one
poweroff function").

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
2018-12-05 23:18:30 +01:00
Ladislav Michl
ab08824826 power: reset: at91-poweroff: Remove redundant dev_err call in at91_poweroff_probe()
There is an error message within devm_ioremap_resource
already, so remove the dev_err call to avoid redundancy.

Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
2018-03-19 20:50:51 +01:00
Ladislav Michl
062836db01 power: reset: at91-poweroff: Switch from the pr_*() to the dev_*() logging functions
Use dev_info() instead of pr_info().

Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
2018-03-19 20:50:24 +01:00
Alexandre Belloni
2e9bbbf694 power: reset: at91-poweroff: fix clobber list
Assembly in at91_lpddr_poweroff has r0 in the clobber list but uses r6.

Reported-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
2017-06-08 13:05:28 +02:00
Alexandre Belloni
0b0408745e power: reset: at91-poweroff: timely shutdown LPDDR memories
LPDDR memories can only handle up to 400 uncontrolled power off. Ensure the
proper power off sequence is used before shutting down the platform.

Cc: <stable@vger.kernel.org> # 4.4+
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
2017-01-16 23:21:33 +01:00
Javier Martinez Canillas
c9ba9b7763 power: reset: at91-poweroff: Fix module autoload
If the driver is built as a module, autoload won't work because the module
alias information is not filled. So user-space can't match the registered
device with the corresponding module.

Export the module alias information using the MODULE_DEVICE_TABLE() macro.

Before this patch:

$ modinfo drivers/power/reset/at91-poweroff.ko | grep alias
$

After this patch:

$ modinfo drivers/power/reset/at91-poweroff.ko | grep alias
alias:          of:N*T*Catmel,at91sam9x5-shdwcC*
alias:          of:N*T*Catmel,at91sam9x5-shdwc
alias:          of:N*T*Catmel,at91sam9rl-shdwcC*
alias:          of:N*T*Catmel,at91sam9rl-shdwc
alias:          of:N*T*Catmel,at91sam9260-shdwcC*
alias:          of:N*T*Catmel,at91sam9260-shdwc

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
2016-10-19 05:16:09 +02:00
Alexandre Belloni
064380a12e power/reset: at91-poweroff: get and use slow clock
Commit dca1a4b5ff6e ("clk: at91: keep slow clk enabled to prevent system
hang") added a workaround for the slow clock as it is not properly handled
by its users.

Get and use the slow clock as it is necessary for the at91 shutdown
controller.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
2015-09-22 15:18:53 +02:00
Alexandre Belloni
6dd1ad1f23 power/reset: at91-poweroff: allow compiling as a module
It was not possible to compile at91-poweroff as a module. Implement
.remove() to allow it. Also switch to module_platform_driver_probe() as it
is not hotpluggable.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
2015-09-22 15:18:53 +02:00
Fabian Frederick
8fb0885504 power: constify of_device_id array
of_device_id is always used as const.
(See driver.of_match_table and open firmware functions)

Signed-off-by: Fabian Frederick <fabf@skynet.be>

[for vexpress]
Acked-by: Sudeep Holla <sudeep.holla@arm.com>

Signed-off-by: Sebastian Reichel <sre@kernel.org>
2015-03-20 13:23:06 +01:00
Guenter Roeck
a538cf04ef power/reset: at91-poweroff: Fix error handling and other compiler warnings
at91_poweroff_get_wakeup_mode can return a negative error code and should
therefore not return an enum type. Similar, its result should not be
assigned to an enum type. Otherwise, the returned value is never negative,
resulting in a compiler warning and a missed error condition, which in turn
results in writing bad values into a chip register.

Also fix other compiler warnings which can be easily avoided.

drivers/power/reset/at91-poweroff.c:74:24:
	warning: type qualifiers ignored on function return type
drivers/power/reset/at91-poweroff.c:74:24:
	warning: no previous prototype for 'at91_poweroff_get_wakeup_mode'
drivers/power/reset/at91-poweroff.c:83:16:
	warning: comparison between signed and unsigned integer expressions
drivers/power/reset/at91-poweroff.c:97:2:
	warning: comparison of unsigned expression < 0 is always false

Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
2015-01-21 20:06:44 +01:00
Nicolas Ferre
405a72c5e7 power: reset: at91-poweroff: fix wakeup status register index
The wakeup status is read from Shutdown Status Register and not the
SHDW_CR which is the one at address 0.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-09-01 18:40:44 +02:00
Maxime Ripard
ae499f0fad power: reset: Add AT91 poweroff driver
Add a driver to handle the shutdown of the Atmel SoCs. This code used to be
(and still is) in arch/arm/mach-at91. We didn't remove it yet so that we can
convert all the boards to using this driver, before removing it entirely in a
separate patch.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2014-07-15 13:40:34 +02:00