Commit Graph

308 Commits

Author SHA1 Message Date
Stephen Gallimore
1f42c290c3 drivers: reset: Reset controller driver for STiH415
This patch adds a reset controller platform driver for the STiH415
SoC. This initial version provides a compatible driver for the
"st,stih415-powerdown" device, which registers a system configuration
register based reset controller that controls the powerdown state of
hardware such as the on-chip USB host controllers.

Signed-off-by: Stephen Gallimore <stephen.gallimore@st.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
2014-03-11 10:49:40 +00:00
Stephen Gallimore
e5d76075d9 drivers: reset: STi SoC system configuration reset controller support
This patch adds a reset controller implementation for STMicroelectronics
STi family SoCs; it allows a group of related reset like controls found
in multiple system configuration registers to be represented by a single
controller device. System configuration registers are accessed through
the regmap framework and the mfd/syscon driver.

The implementation optionally supports waiting for the reset action to
be acknowledged in a separate status register and supports both
active high and active low reset lines. These properties are common across
all the reset channels in a specific reset controller instance, hence
all channels in a paritcular controller are expected to behave in the
same way.

Signed-off-by: Stephen Gallimore <stephen.gallimore@st.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
2014-03-11 10:47:23 +00:00
Maxime Ripard
fc0a592156 reset: Add of_reset_control_get
In some cases, you might need to deassert from reset an hardware block that
doesn't associated to a struct device (CPUs, timers, etc.).

Add a small helper to retrieve the reset controller from the device tree
without the need to pass a struct device.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2014-02-03 10:19:40 +01:00
Rashika Kheria
0c5b2b915a reset: Mark function as static and remove unused function in core.c
Mark function of_reset_simple_xlate() as static in core.c
because it is not used outside this file.
Also, remove functions devm_reset_control_put() and
devm_reset_control_match() because they are unused.

This eliminates the following warnings in core.c:
drivers/reset/core.c:46:5: warning: no previous prototype for ‘of_reset_simple_xlate’ [-Wmissing-prototypes]
drivers/reset/core.c:262:6: warning: no previous prototype for ‘devm_reset_control_put’ [-Wmissing-prototypes]

Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2014-02-03 10:19:40 +01:00
Philipp Zabel
3d10302048 reset: allow drivers to request probe deferral
If the requested reset controller is not yet available, have reset_control_get
and device_reset return -EPROBE_DEFER so the driver can decide to request
probe deferral.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
2014-02-03 10:19:39 +01:00
Maxime Ripard
8f1ae77f46 reset: Add Allwinner SoCs Reset Controller Driver
The Allwinner A31 and most of the other Allwinner SoCs have an IP
maintaining a few other IPs in the SoC in reset by default. Among these
IPs are the A31's High Speed Timers, hence why we can't use the regular
driver construct in every cases, and need to call the registering
function directly during machine initialisation.

Apart from this, the implementation is fairly straightforward, and could
easily be moved to a generic MMIO-based reset controller driver if the
need ever arise.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
2013-11-22 21:20:36 +01:00
Dan Carpenter
6034bb22d8 reset: NULL deref on allocation failure
"rstc" is NULL here and we should use "rcdev" instead of "rstc->rcdev".

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2013-04-12 10:26:24 +02:00
Philipp Zabel
61fc413176 reset: Add reset controller API
This adds a simple API for devices to request being reset
by separate reset controller hardware and implements the
reset signal device tree binding.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Marek Vasut <marex@denx.de>
Reviewed-by: Pavel Machek <pavel@ucw.cz>
2013-04-12 10:26:23 +02:00