3 files changed, 237 insertions, 0 deletions

diff --git a/net/rfkill/Kconfig b/net/rfkill/Kconfig
index 48464ca13b24..78efe895b663 100644
--- a/net/rfkill/Kconfig
+++ b/net/rfkill/Kconfig
@@ -33,3 +33,12 @@ config RFKILL_REGULATOR
 
           To compile this driver as a module, choose M here: the module will
           be called rfkill-regulator.
+
+config RFKILL_GPIO
+        tristate "GPIO RFKILL driver"
+        depends on RFKILL && GPIOLIB && HAVE_CLK
+        default n
+        help
+          If you say yes here you get support of a generic gpio RFKILL
+          driver. The platform should fill in the appropriate fields in the
+          rfkill_gpio_platform_data structure and pass that to the driver.
diff --git a/net/rfkill/Makefile b/net/rfkill/Makefile
index d9a5a58ffd8c..311768783f4a 100644
--- a/net/rfkill/Makefile
+++ b/net/rfkill/Makefile
@@ -6,3 +6,4 @@ rfkill-y			+= core.o
 rfkill-$(CONFIG_RFKILL_INPUT)   += input.o
 obj-$(CONFIG_RFKILL)            += rfkill.o
 obj-$(CONFIG_RFKILL_REGULATOR)  += rfkill-regulator.o
+obj-$(CONFIG_RFKILL_GPIO)       += rfkill-gpio.o
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");