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linux/arch/arm/mach-tegra/board-pinmux.c
Stephen Warren a58116f331 arm/tegra: Use bus notifiers to trigger pinmux setup
Currently, the Tegra pinmux is initialized at different times when booting
with and without device tree:

Without device tree:

1) Pinmux and GPIO drivers are registered.
2) Pinmux is configured.
3) All other drivers are registered.

With device tree:

1) All drivers are registered and probed, including pinmux and GPIO.
2) Pinmux is configured.

This change modifies board-pinmux.c to detect pinmux and GPIO driver
registration using bus notifiers. This allows pinmux configuration to
happen immediately after the pinmux driver is probed, irrespective of
whether the pinmux driver is manually registered by board-pinmux.c, or
if it's instantiated during device tree parsing.

To support this with device tree, the pinmux init functions must be
called prior to instantiating devices from device tree, so that the
notifiers are set up before-hand.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2011-12-19 18:03:11 -08:00

105 lines
2.4 KiB
C

/*
* Copyright (c) 2011, NVIDIA CORPORATION. All rights reserved.
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*/
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/notifier.h>
#include <linux/of.h>
#include <linux/string.h>
#include <mach/gpio-tegra.h>
#include <mach/pinmux.h>
#include "board-pinmux.h"
#include "devices.h"
struct tegra_board_pinmux_conf *confs[2];
static void tegra_board_pinmux_setup_gpios(void)
{
int i;
for (i = 0; i < ARRAY_SIZE(confs); i++) {
if (!confs[i])
continue;
tegra_gpio_config(confs[i]->gpios, confs[i]->gpio_count);
}
}
static void tegra_board_pinmux_setup_pinmux(void)
{
int i;
for (i = 0; i < ARRAY_SIZE(confs); i++) {
if (!confs[i])
continue;
tegra_pinmux_config_table(confs[i]->pgs, confs[i]->pg_count);
if (confs[i]->drives)
tegra_drive_pinmux_config_table(confs[i]->drives,
confs[i]->drive_count);
}
}
static int tegra_board_pinmux_bus_notify(struct notifier_block *nb,
unsigned long event, void *vdev)
{
static bool had_gpio;
static bool had_pinmux;
struct device *dev = vdev;
const char *devname;
if (event != BUS_NOTIFY_BOUND_DRIVER)
return NOTIFY_DONE;
devname = dev_name(dev);
if (!had_gpio && !strcmp(devname, GPIO_DEV)) {
tegra_board_pinmux_setup_gpios();
had_gpio = true;
} else if (!had_pinmux && !strcmp(devname, PINMUX_DEV)) {
tegra_board_pinmux_setup_pinmux();
had_pinmux = true;
}
if (had_gpio && had_pinmux)
return NOTIFY_STOP_MASK;
else
return NOTIFY_DONE;
}
static struct notifier_block nb = {
.notifier_call = tegra_board_pinmux_bus_notify,
};
static struct platform_device *devices[] = {
&tegra_gpio_device,
&tegra_pinmux_device,
};
void tegra_board_pinmux_init(struct tegra_board_pinmux_conf *conf_a,
struct tegra_board_pinmux_conf *conf_b)
{
confs[0] = conf_a;
confs[1] = conf_b;
bus_register_notifier(&platform_bus_type, &nb);
if (!of_machine_is_compatible("nvidia,tegra20"))
platform_add_devices(devices, ARRAY_SIZE(devices));
}