/*
* Copyright (c) 2011, NVIDIA Corporation.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* 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.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include <linux/gpio.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/rfkill.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/slab.h>
#include <linux/rfkill-gpio.h>
enum rfkill_gpio_clk_state {
UNSPECIFIED = 0,
PWR_ENABLED,
PWR_DISABLED
};
#define PWR_CLK_SET(_RF, _EN) \
((_RF)->pwr_clk_enabled = (!(_EN) ? PWR_ENABLED : PWR_DISABLED))
#define PWR_CLK_ENABLED(_RF) ((_RF)->pwr_clk_enabled == PWR_ENABLED)
#define PWR_CLK_DISABLED(_RF) ((_RF)->pwr_clk_enabled != PWR_ENABLED)
struct rfkill_gpio_data {
struct rfkill_gpio_platform_data *pdata;
struct rfkill *rfkill_dev;
char *reset_name;
char *shutdown_name;
enum rfkill_gpio_clk_state pwr_clk_enabled;
struct clk *pwr_clk;
};
static int rfkill_gpio_set_power(void *data, bool blocked)
{
struct rfkill_gpio_data *rfkill = data;
if (blocked) {
if (gpio_is_valid(rfkill->pdata->shutdown_gpio))
gpio_direction_output(rfkill->pdata->shutdown_gpio, 0);
if (gpio_is_valid(rfkill->pdata->reset_gpio))
gpio_direction_output(rfkill->pdata->reset_gpio, 0);
if (rfkill->pwr_clk && PWR_CLK_ENABLED(rfkill))
clk_disable(rfkill->pwr_clk);
} else {
if (rfkill->pwr_clk && PWR_CLK_DISABLED(rfkill))
clk_enable(rfkill->pwr_clk);
if (gpio_is_valid(rfkill->pdata->reset_gpio))
gpio_direction_output(rfkill->pdata->reset_gpio, 1);
if (gpio_is_valid(rfkill->pdata->shutdown_gpio))
gpio_direction_output(rfkill->pdata->shutdown_gpio, 1);
}
if (rfkill->pwr_clk)
PWR_CLK_SET(rfkill, blocked);
return 0;
}
static const struct rfkill_ops rfkill_gpio_ops = {
.set_block = rfkill_gpio_set_power,
};
static int rfkill_gpio_probe(struct platform_device *pdev)
{
struct rfkill_gpio_data *rfkill;
struct rfkill_gpio_platform_data *pdata = pdev->dev.platform_data;
int ret = 0;
int len = 0;
if (!pdata) {
pr_warn("%s: No platform data specified\n", __func__);
return -EINVAL;
}
/* make sure at-least one of the GPIO is defined and that
* a name is specified for this instance */
if (!pdata->name || (!gpio_is_valid(pdata->reset_gpio) &&
!gpio_is_valid(pdata->shutdown_gpio))) {
pr_warn("%s: invalid platform data\n", __func__);
return -EINVAL;
}
rfkill = kzalloc(sizeof(*rfkill), GFP_KERNEL);
if (!rfkill)
return -ENOMEM;
rfkill->pdata = pdata;
len = strlen(pdata->name);
rfkill->reset_name = kzalloc(len + 7, GFP_KERNEL);
if (!rfkill->reset_name) {
ret = -ENOMEM;
goto fail_alloc;
}
rfkill->shutdown_name = kzalloc(len + 10, GFP_KERNEL);
if (!rfkill->shutdown_name) {
ret = -ENOMEM;
goto fail_reset_name;
}
snprintf(rfkill->reset_name, len + 6 , "%s_reset", pdata->name);
snprintf(rfkill->shutdown_name, len + 9, "%s_shutdown", pdata->name);
if (pdata->power_clk_name) {
rfkill->pwr_clk = clk_get(&pdev->dev, pdata->power_clk_name);
if (IS_ERR(rfkill->pwr_clk)) {
pr_warn("%s: can't find pwr_clk.\n", __func__);
goto fail_shutdown_name;
}
}
if (gpio_is_valid(pdata->reset_gpio)) {
ret = gpio_request(pdata->reset_gpio, rfkill->reset_name);
if (ret) {
pr_warn("%s: failed to get reset gpio.\n", __func__);
goto fail_clock;
}
}
if (gpio_is_valid(pdata->shutdown_gpio)) {
ret = gpio_request(pdata->shutdown_gpio, rfkill->shutdown_name);
if (ret) {
pr_warn("%s: failed to get shutdown gpio.\n", __func__);
goto fail_reset;
}
}
rfkill->rfkill_dev = rfkill_alloc(pdata->name, &pdev->dev, pdata->type,
&rfkill_gpio_ops, rfkill);
if (!rfkill->rfkill_dev)
goto fail_shutdown;
ret = rfkill_register(rfkill->rfkill_dev);
if (ret < 0)
goto fail_rfkill;
platform_set_drvdata(pdev, rfkill);
dev_info(&pdev->dev, "%s device registered.\n", pdata->name);
return 0;
fail_rfkill:
rfkill_destroy(rfkill->rfkill_dev);
fail_shutdown:
if (gpio_is_valid(pdata->shutdown_gpio))
gpio_free(pdata->shutdown_gpio);
fail_reset:
if (gpio_is_valid(pdata->reset_gpio))
gpio_free(pdata->reset_gpio);
fail_clock:
if (rfkill->pwr_clk)
clk_put(rfkill->pwr_clk);
fail_shutdown_name:
kfree(rfkill->shutdown_name);
fail_reset_name:
kfree(rfkill->reset_name);
fail_alloc:
kfree(rfkill);
return ret;
}
static int rfkill_gpio_remove(struct platform_device *pdev)
{
struct rfkill_gpio_data *rfkill = platform_get_drvdata(pdev);
rfkill_unregister(rfkill->rfkill_dev);
rfkill_destroy(rfkill->rfkill_dev);
if (gpio_is_valid(rfkill->pdata->shutdown_gpio))
gpio_free(rfkill->pdata->shutdown_gpio);
if (gpio_is_valid(rfkill->pdata->reset_gpio))
gpio_free(rfkill->pdata->reset_gpio);
if (rfkill->pwr_clk && PWR_CLK_ENABLED(rfkill))
clk_disable(rfkill->pwr_clk);
if (rfkill->pwr_clk)
clk_put(rfkill->pwr_clk);
kfree(rfkill->shutdown_name);
kfree(rfkill->reset_name);
kfree(rfkill);
return 0;
}
static struct platform_driver rfkill_gpio_driver = {
.probe = rfkill_gpio_probe,
.remove = __devexit_p(rfkill_gpio_remove),
.driver = {
.name = "rfkill_gpio",
.owner = THIS_MODULE,
},
};
static int __init rfkill_gpio_init(void)
{
return platform_driver_register(&rfkill_gpio_driver);
}
static void __exit rfkill_gpio_exit(void)
{
platform_driver_unregister(&rfkill_gpio_driver);
}
module_init(rfkill_gpio_init);
module_exit(rfkill_gpio_exit);
MODULE_DESCRIPTION("gpio rfkill");
MODULE_AUTHOR("NVIDIA");
MODULE_LICENSE("GPL");
