summaryrefslogtreecommitdiff
path: root/net/rfkill/rfkill-gpio.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/rfkill/rfkill-gpio.c')
-rw-r--r--net/rfkill/rfkill-gpio.c227
1 files changed, 227 insertions, 0 deletions
diff --git a/net/rfkill/rfkill-gpio.c b/net/rfkill/rfkill-gpio.c
new file mode 100644
index 000000000000..256c5ddd2d72
--- /dev/null
+++ b/net/rfkill/rfkill-gpio.c
@@ -0,0 +1,227 @@
+/*
+ * 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");