rfkill: Regulator consumer driver for rfkill

Add a regulator consumer driver for rfkill to enable controlling radio
transmitters connected to voltage regulators using the regulator
framework.

A new "vrfkill" virtual supply is provided to use in platform code.

Signed-off-by: Guiming Zhuo <gmzhuo@gmail.com>
Signed-off-by: Antonio Ospite <ospite@studenti.unina.it>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

3 files changed, 176 insertions, 0 deletions

diff --git a/net/rfkill/Kconfig b/net/rfkill/Kconfig
index 7fce6dfd2180..48464ca13b24 100644
--- a/net/rfkill/Kconfig
+++ b/net/rfkill/Kconfig
@@ -22,3 +22,14 @@ config RFKILL_INPUT
         depends on RFKILL
         depends on INPUT = y || RFKILL = INPUT
         default y if !EXPERT
+
+config RFKILL_REGULATOR
+        tristate "Generic rfkill regulator driver"
+        depends on RFKILL || !RFKILL
+        depends on REGULATOR
+        help
+          This options enable controlling radio transmitters connected to
+          voltage regulator using the regulator framework.
+
+          To compile this driver as a module, choose M here: the module will
+          be called rfkill-regulator.
diff --git a/net/rfkill/Makefile b/net/rfkill/Makefile
index 662105352691..d9a5a58ffd8c 100644
--- a/net/rfkill/Makefile
+++ b/net/rfkill/Makefile
@@ -5,3 +5,4 @@
 rfkill-y                        += core.o
 rfkill-$(CONFIG_RFKILL_INPUT)   += input.o
 obj-$(CONFIG_RFKILL)            += rfkill.o
+obj-$(CONFIG_RFKILL_REGULATOR)  += rfkill-regulator.o
diff --git a/net/rfkill/rfkill-regulator.c b/net/rfkill/rfkill-regulator.c
new file mode 100644
index 000000000000..18dc512a10f3
--- /dev/null
+++ b/net/rfkill/rfkill-regulator.c
@@ -0,0 +1,164 @@
+/*
+ * rfkill-regulator.c - Regulator consumer driver for rfkill
+ *
+ * Copyright (C) 2009  Guiming Zhuo <gmzhuo@gmail.com>
+ * Copyright (C) 2011  Antonio Ospite <ospite@studenti.unina.it>
+ *
+ * Implementation inspired by leds-regulator driver.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/rfkill.h>
+#include <linux/rfkill-regulator.h>
+
+struct rfkill_regulator_data {
+        struct rfkill *rf_kill;
+        bool reg_enabled;
+
+        struct regulator *vcc;
+};
+
+static int rfkill_regulator_set_block(void *data, bool blocked)
+{
+        struct rfkill_regulator_data *rfkill_data = data;
+
+        pr_debug("%s: blocked: %d\n", __func__, blocked);
+
+        if (blocked) {
+                if (rfkill_data->reg_enabled) {
+                        regulator_disable(rfkill_data->vcc);
+                        rfkill_data->reg_enabled = 0;
+                }
+        } else {
+                if (!rfkill_data->reg_enabled) {
+                        regulator_enable(rfkill_data->vcc);
+                        rfkill_data->reg_enabled = 1;
+                }
+        }
+
+        pr_debug("%s: regulator_is_enabled after set_block: %d\n", __func__,
+                regulator_is_enabled(rfkill_data->vcc));
+
+        return 0;
+}
+
+struct rfkill_ops rfkill_regulator_ops = {
+        .set_block = rfkill_regulator_set_block,
+};
+
+static int __devinit rfkill_regulator_probe(struct platform_device *pdev)
+{
+        struct rfkill_regulator_platform_data *pdata = pdev->dev.platform_data;
+        struct rfkill_regulator_data *rfkill_data;
+        struct regulator *vcc;
+        struct rfkill *rf_kill;
+        int ret = 0;
+
+        if (pdata == NULL) {
+                dev_err(&pdev->dev, "no platform data\n");
+                return -ENODEV;
+        }
+
+        if (pdata->name == NULL || pdata->type == 0) {
+                dev_err(&pdev->dev, "invalid name or type in platform data\n");
+                return -EINVAL;
+        }
+
+        vcc = regulator_get_exclusive(&pdev->dev, "vrfkill");
+        if (IS_ERR(vcc)) {
+                dev_err(&pdev->dev, "Cannot get vcc for %s\n", pdata->name);
+                ret = PTR_ERR(vcc);
+                goto out;
+        }
+
+        rfkill_data = kzalloc(sizeof(*rfkill_data), GFP_KERNEL);
+        if (rfkill_data == NULL) {
+                ret = -ENOMEM;
+                goto err_data_alloc;
+        }
+
+        rf_kill = rfkill_alloc(pdata->name, &pdev->dev,
+                                pdata->type,
+                                &rfkill_regulator_ops, rfkill_data);
+        if (rf_kill == NULL) {
+                dev_err(&pdev->dev, "Cannot alloc rfkill device\n");
+                ret = -ENOMEM;
+                goto err_rfkill_alloc;
+        }
+
+        if (regulator_is_enabled(vcc)) {
+                dev_dbg(&pdev->dev, "Regulator already enabled\n");
+                rfkill_data->reg_enabled = 1;
+        }
+        rfkill_data->vcc = vcc;
+        rfkill_data->rf_kill = rf_kill;
+
+        ret = rfkill_register(rf_kill);
+        if (ret) {
+                dev_err(&pdev->dev, "Cannot register rfkill device\n");
+                goto err_rfkill_register;
+        }
+
+        platform_set_drvdata(pdev, rfkill_data);
+        dev_info(&pdev->dev, "%s initialized\n", pdata->name);
+
+        return 0;
+
+err_rfkill_register:
+        rfkill_destroy(rf_kill);
+err_rfkill_alloc:
+        kfree(rfkill_data);
+err_data_alloc:
+        regulator_put(vcc);
+out:
+        return ret;
+}
+
+static int __devexit rfkill_regulator_remove(struct platform_device *pdev)
+{
+        struct rfkill_regulator_data *rfkill_data = platform_get_drvdata(pdev);
+        struct rfkill *rf_kill = rfkill_data->rf_kill;
+
+        rfkill_unregister(rf_kill);
+        rfkill_destroy(rf_kill);
+        regulator_put(rfkill_data->vcc);
+        kfree(rfkill_data);
+
+        return 0;
+}
+
+static struct platform_driver rfkill_regulator_driver = {
+        .probe = rfkill_regulator_probe,
+        .remove = __devexit_p(rfkill_regulator_remove),
+        .driver = {
+                .name = "rfkill-regulator",
+                .owner = THIS_MODULE,
+        },
+};
+
+static int __init rfkill_regulator_init(void)
+{
+        return platform_driver_register(&rfkill_regulator_driver);
+}
+module_init(rfkill_regulator_init);
+
+static void __exit rfkill_regulator_exit(void)
+{
+        platform_driver_unregister(&rfkill_regulator_driver);
+}
+module_exit(rfkill_regulator_exit);
+
+MODULE_AUTHOR("Guiming Zhuo <gmzhuo@gmail.com>");
+MODULE_AUTHOR("Antonio Ospite <ospite@studenti.unina.it>");
+MODULE_DESCRIPTION("Regulator consumer driver for rfkill");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:rfkill-regulator");