kernel-ark/drivers/base/pinctrl.c
Linus Walleij 14005ee270 drivers: pinctrl sleep and idle states in the core
If a device have sleep and idle states in addition to the
default state, look up these in the core and stash them in
the pinctrl state container.

Add accessor functions for pinctrl consumers to put the pins
into "default", "sleep" and "idle" states passing nothing but
the struct device * affected.

Solution suggested by Kevin Hilman, Mark Brown and Dmitry
Torokhov in response to a patch series from Hebbar
Gururaja.

Cc: Hebbar Gururaja <gururaja.hebbar@ti.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-06-16 11:56:52 +02:00

89 lines
2.2 KiB
C

/*
* Driver core interface to the pinctrl subsystem.
*
* Copyright (C) 2012 ST-Ericsson SA
* Written on behalf of Linaro for ST-Ericsson
* Based on bits of regulator core, gpio core and clk core
*
* Author: Linus Walleij <linus.walleij@linaro.org>
*
* License terms: GNU General Public License (GPL) version 2
*/
#include <linux/device.h>
#include <linux/pinctrl/devinfo.h>
#include <linux/pinctrl/consumer.h>
#include <linux/slab.h>
/**
* pinctrl_bind_pins() - called by the device core before probe
* @dev: the device that is just about to probe
*/
int pinctrl_bind_pins(struct device *dev)
{
int ret;
dev->pins = devm_kzalloc(dev, sizeof(*(dev->pins)), GFP_KERNEL);
if (!dev->pins)
return -ENOMEM;
dev->pins->p = devm_pinctrl_get(dev);
if (IS_ERR(dev->pins->p)) {
dev_dbg(dev, "no pinctrl handle\n");
ret = PTR_ERR(dev->pins->p);
goto cleanup_alloc;
}
dev->pins->default_state = pinctrl_lookup_state(dev->pins->p,
PINCTRL_STATE_DEFAULT);
if (IS_ERR(dev->pins->default_state)) {
dev_dbg(dev, "no default pinctrl state\n");
ret = 0;
goto cleanup_get;
}
ret = pinctrl_select_state(dev->pins->p, dev->pins->default_state);
if (ret) {
dev_dbg(dev, "failed to activate default pinctrl state\n");
goto cleanup_get;
}
#ifdef CONFIG_PM
/*
* If power management is enabled, we also look for the optional
* sleep and idle pin states, with semantics as defined in
* <linux/pinctrl/pinctrl-state.h>
*/
dev->pins->sleep_state = pinctrl_lookup_state(dev->pins->p,
PINCTRL_STATE_SLEEP);
if (IS_ERR(dev->pins->sleep_state))
/* Not supplying this state is perfectly legal */
dev_dbg(dev, "no sleep pinctrl state\n");
dev->pins->idle_state = pinctrl_lookup_state(dev->pins->p,
PINCTRL_STATE_IDLE);
if (IS_ERR(dev->pins->idle_state))
/* Not supplying this state is perfectly legal */
dev_dbg(dev, "no idle pinctrl state\n");
#endif
return 0;
/*
* If no pinctrl handle or default state was found for this device,
* let's explicitly free the pin container in the device, there is
* no point in keeping it around.
*/
cleanup_get:
devm_pinctrl_put(dev->pins->p);
cleanup_alloc:
devm_kfree(dev, dev->pins);
dev->pins = NULL;
/* Only return deferrals */
if (ret != -EPROBE_DEFER)
ret = 0;
return ret;
}