1 files changed, 431 insertions, 0 deletions
diff --git a/drivers/staging/wimax/op-rfkill.c b/drivers/staging/wimax/op-rfkill.c
new file mode 100644
index 000000000000..78b294481a59
--- /dev/null
+++ b/drivers/staging/wimax/op-rfkill.c
@@ -0,0 +1,431 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Linux WiMAX
+ * RF-kill framework integration
+ *
+ * Copyright (C) 2008 Intel Corporation <linux-wimax@intel.com>
+ * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
+ *
+ * This integrates into the Linux Kernel rfkill susbystem so that the
+ * drivers just have to do the bare minimal work, which is providing a
+ * method to set the software RF-Kill switch and to report changes in
+ * the software and hardware switch status.
+ *
+ * A non-polled generic rfkill device is embedded into the WiMAX
+ * subsystem's representation of a device.
+ *
+ * FIXME: Need polled support? Let drivers provide a poll routine
+ *	  and hand it to rfkill ops then?
+ *
+ * All device drivers have to do is after wimax_dev_init(), call
+ * wimax_report_rfkill_hw() and wimax_report_rfkill_sw() to update
+ * initial state and then every time it changes. See wimax.h:struct
+ * wimax_dev for more information.
+ *
+ * ROADMAP
+ *
+ * wimax_gnl_doit_rfkill()      User space calling wimax_rfkill()
+ *   wimax_rfkill()             Kernel calling wimax_rfkill()
+ *     __wimax_rf_toggle_radio()
+ *
+ * wimax_rfkill_set_radio_block()  RF-Kill subsystem calling
+ *   __wimax_rf_toggle_radio()
+ *
+ * __wimax_rf_toggle_radio()
+ *   wimax_dev->op_rfkill_sw_toggle() Driver backend
+ *   __wimax_state_change()
+ *
+ * wimax_report_rfkill_sw()     Driver reports state change
+ *   __wimax_state_change()
+ *
+ * wimax_report_rfkill_hw()     Driver reports state change
+ *   __wimax_state_change()
+ *
+ * wimax_rfkill_add()           Initialize/shutdown rfkill support
+ * wimax_rfkill_rm()            [called by wimax_dev_add/rm()]
+ */
+
+#include "net-wimax.h"
+#include <net/genetlink.h>
+#include "linux-wimax.h"
+#include <linux/security.h>
+#include <linux/rfkill.h>
+#include <linux/export.h>
+#include "wimax-internal.h"
+
+#define D_SUBMODULE op_rfkill
+#include "debug-levels.h"
+
+/**
+ * wimax_report_rfkill_hw - Reports changes in the hardware RF switch
+ *
+ * @wimax_dev: WiMAX device descriptor
+ *
+ * @state: New state of the RF Kill switch. %WIMAX_RF_ON radio on,
+ *     %WIMAX_RF_OFF radio off.
+ *
+ * When the device detects a change in the state of thehardware RF
+ * switch, it must call this function to let the WiMAX kernel stack
+ * know that the state has changed so it can be properly propagated.
+ *
+ * The WiMAX stack caches the state (the driver doesn't need to). As
+ * well, as the change is propagated it will come back as a request to
+ * change the software state to mirror the hardware state.
+ *
+ * If the device doesn't have a hardware kill switch, just report
+ * it on initialization as always on (%WIMAX_RF_ON, radio on).
+ */
+void wimax_report_rfkill_hw(struct wimax_dev *wimax_dev,
+			    enum wimax_rf_state state)
+{
+	int result;
+	struct device *dev = wimax_dev_to_dev(wimax_dev);
+	enum wimax_st wimax_state;
+
+	d_fnstart(3, dev, "(wimax_dev %p state %u)\n", wimax_dev, state);
+	BUG_ON(state == WIMAX_RF_QUERY);
+	BUG_ON(state != WIMAX_RF_ON && state != WIMAX_RF_OFF);
+
+	mutex_lock(&wimax_dev->mutex);
+	result = wimax_dev_is_ready(wimax_dev);
+	if (result < 0)
+		goto error_not_ready;
+
+	if (state != wimax_dev->rf_hw) {
+		wimax_dev->rf_hw = state;
+		if (wimax_dev->rf_hw == WIMAX_RF_ON &&
+		    wimax_dev->rf_sw == WIMAX_RF_ON)
+			wimax_state = WIMAX_ST_READY;
+		else
+			wimax_state = WIMAX_ST_RADIO_OFF;
+
+		result = rfkill_set_hw_state(wimax_dev->rfkill,
+					     state == WIMAX_RF_OFF);
+
+		__wimax_state_change(wimax_dev, wimax_state);
+	}
+error_not_ready:
+	mutex_unlock(&wimax_dev->mutex);
+	d_fnend(3, dev, "(wimax_dev %p state %u) = void [%d]\n",
+		wimax_dev, state, result);
+}
+EXPORT_SYMBOL_GPL(wimax_report_rfkill_hw);
+
+
+/**
+ * wimax_report_rfkill_sw - Reports changes in the software RF switch
+ *
+ * @wimax_dev: WiMAX device descriptor
+ *
+ * @state: New state of the RF kill switch. %WIMAX_RF_ON radio on,
+ *     %WIMAX_RF_OFF radio off.
+ *
+ * Reports changes in the software RF switch state to the WiMAX stack.
+ *
+ * The main use is during initialization, so the driver can query the
+ * device for its current software radio kill switch state and feed it
+ * to the system.
+ *
+ * On the side, the device does not change the software state by
+ * itself. In practice, this can happen, as the device might decide to
+ * switch (in software) the radio off for different reasons.
+ */
+void wimax_report_rfkill_sw(struct wimax_dev *wimax_dev,
+			    enum wimax_rf_state state)
+{
+	int result;
+	struct device *dev = wimax_dev_to_dev(wimax_dev);
+	enum wimax_st wimax_state;
+
+	d_fnstart(3, dev, "(wimax_dev %p state %u)\n", wimax_dev, state);
+	BUG_ON(state == WIMAX_RF_QUERY);
+	BUG_ON(state != WIMAX_RF_ON && state != WIMAX_RF_OFF);
+
+	mutex_lock(&wimax_dev->mutex);
+	result = wimax_dev_is_ready(wimax_dev);
+	if (result < 0)
+		goto error_not_ready;
+
+	if (state != wimax_dev->rf_sw) {
+		wimax_dev->rf_sw = state;
+		if (wimax_dev->rf_hw == WIMAX_RF_ON &&
+		    wimax_dev->rf_sw == WIMAX_RF_ON)
+			wimax_state = WIMAX_ST_READY;
+		else
+			wimax_state = WIMAX_ST_RADIO_OFF;
+		__wimax_state_change(wimax_dev, wimax_state);
+		rfkill_set_sw_state(wimax_dev->rfkill, state == WIMAX_RF_OFF);
+	}
+error_not_ready:
+	mutex_unlock(&wimax_dev->mutex);
+	d_fnend(3, dev, "(wimax_dev %p state %u) = void [%d]\n",
+		wimax_dev, state, result);
+}
+EXPORT_SYMBOL_GPL(wimax_report_rfkill_sw);
+
+
+/*
+ * Callback for the RF Kill toggle operation
+ *
+ * This function is called by:
+ *
+ * - The rfkill subsystem when the RF-Kill key is pressed in the
+ *   hardware and the driver notifies through
+ *   wimax_report_rfkill_hw(). The rfkill subsystem ends up calling back
+ *   here so the software RF Kill switch state is changed to reflect
+ *   the hardware switch state.
+ *
+ * - When the user sets the state through sysfs' rfkill/state file
+ *
+ * - When the user calls wimax_rfkill().
+ *
+ * This call blocks!
+ *
+ * WARNING! When we call rfkill_unregister(), this will be called with
+ * state 0!
+ *
+ * WARNING: wimax_dev must be locked
+ */
+static
+int __wimax_rf_toggle_radio(struct wimax_dev *wimax_dev,
+			    enum wimax_rf_state state)
+{
+	int result = 0;
+	struct device *dev = wimax_dev_to_dev(wimax_dev);
+	enum wimax_st wimax_state;
+
+	might_sleep();
+	d_fnstart(3, dev, "(wimax_dev %p state %u)\n", wimax_dev, state);
+	if (wimax_dev->rf_sw == state)
+		goto out_no_change;
+	if (wimax_dev->op_rfkill_sw_toggle != NULL)
+		result = wimax_dev->op_rfkill_sw_toggle(wimax_dev, state);
+	else if (state == WIMAX_RF_OFF)	/* No op? can't turn off */
+		result = -ENXIO;
+	else				/* No op? can turn on */
+		result = 0;		/* should never happen tho */
+	if (result >= 0) {
+		result = 0;
+		wimax_dev->rf_sw = state;
+		wimax_state = state == WIMAX_RF_ON ?
+			WIMAX_ST_READY : WIMAX_ST_RADIO_OFF;
+		__wimax_state_change(wimax_dev, wimax_state);
+	}
+out_no_change:
+	d_fnend(3, dev, "(wimax_dev %p state %u) = %d\n",
+		wimax_dev, state, result);
+	return result;
+}
+
+
+/*
+ * Translate from rfkill state to wimax state
+ *
+ * NOTE: Special state handling rules here
+ *
+ *     Just pretend the call didn't happen if we are in a state where
+ *     we know for sure it cannot be handled (WIMAX_ST_DOWN or
+ *     __WIMAX_ST_QUIESCING). rfkill() needs it to register and
+ *     unregister, as it will run this path.
+ *
+ * NOTE: This call will block until the operation is completed.
+ */
+static int wimax_rfkill_set_radio_block(void *data, bool blocked)
+{
+	int result;
+	struct wimax_dev *wimax_dev = data;
+	struct device *dev = wimax_dev_to_dev(wimax_dev);
+	enum wimax_rf_state rf_state;
+
+	d_fnstart(3, dev, "(wimax_dev %p blocked %u)\n", wimax_dev, blocked);
+	rf_state = WIMAX_RF_ON;
+	if (blocked)
+		rf_state = WIMAX_RF_OFF;
+	mutex_lock(&wimax_dev->mutex);
+	if (wimax_dev->state <= __WIMAX_ST_QUIESCING)
+		result = 0;
+	else
+		result = __wimax_rf_toggle_radio(wimax_dev, rf_state);
+	mutex_unlock(&wimax_dev->mutex);
+	d_fnend(3, dev, "(wimax_dev %p blocked %u) = %d\n",
+		wimax_dev, blocked, result);
+	return result;
+}
+
+static const struct rfkill_ops wimax_rfkill_ops = {
+	.set_block = wimax_rfkill_set_radio_block,
+};
+
+/**
+ * wimax_rfkill - Set the software RF switch state for a WiMAX device
+ *
+ * @wimax_dev: WiMAX device descriptor
+ *
+ * @state: New RF state.
+ *
+ * Returns:
+ *
+ * >= 0 toggle state if ok, < 0 errno code on error. The toggle state
+ * is returned as a bitmap, bit 0 being the hardware RF state, bit 1
+ * the software RF state.
+ *
+ * 0 means disabled (%WIMAX_RF_ON, radio on), 1 means enabled radio
+ * off (%WIMAX_RF_OFF).
+ *
+ * Description:
+ *
+ * Called by the user when he wants to request the WiMAX radio to be
+ * switched on (%WIMAX_RF_ON) or off (%WIMAX_RF_OFF). With
+ * %WIMAX_RF_QUERY, just the current state is returned.
+ *
+ * NOTE:
+ *
+ * This call will block until the operation is complete.
+ */
+int wimax_rfkill(struct wimax_dev *wimax_dev, enum wimax_rf_state state)
+{
+	int result;
+	struct device *dev = wimax_dev_to_dev(wimax_dev);
+
+	d_fnstart(3, dev, "(wimax_dev %p state %u)\n", wimax_dev, state);
+	mutex_lock(&wimax_dev->mutex);
+	result = wimax_dev_is_ready(wimax_dev);
+	if (result < 0) {
+		/* While initializing, < 1.4.3 wimax-tools versions use
+		 * this call to check if the device is a valid WiMAX
+		 * device; so we allow it to proceed always,
+		 * considering the radios are all off. */
+		if (result == -ENOMEDIUM && state == WIMAX_RF_QUERY)
+			result = WIMAX_RF_OFF << 1 | WIMAX_RF_OFF;
+		goto error_not_ready;
+	}
+	switch (state) {
+	case WIMAX_RF_ON:
+	case WIMAX_RF_OFF:
+		result = __wimax_rf_toggle_radio(wimax_dev, state);
+		if (result < 0)
+			goto error;
+		rfkill_set_sw_state(wimax_dev->rfkill, state == WIMAX_RF_OFF);
+		break;
+	case WIMAX_RF_QUERY:
+		break;
+	default:
+		result = -EINVAL;
+		goto error;
+	}
+	result = wimax_dev->rf_sw << 1 | wimax_dev->rf_hw;
+error:
+error_not_ready:
+	mutex_unlock(&wimax_dev->mutex);
+	d_fnend(3, dev, "(wimax_dev %p state %u) = %d\n",
+		wimax_dev, state, result);
+	return result;
+}
+EXPORT_SYMBOL(wimax_rfkill);
+
+
+/*
+ * Register a new WiMAX device's RF Kill support
+ *
+ * WARNING: wimax_dev->mutex must be unlocked
+ */
+int wimax_rfkill_add(struct wimax_dev *wimax_dev)
+{
+	int result;
+	struct rfkill *rfkill;
+	struct device *dev = wimax_dev_to_dev(wimax_dev);
+
+	d_fnstart(3, dev, "(wimax_dev %p)\n", wimax_dev);
+	/* Initialize RF Kill */
+	result = -ENOMEM;
+	rfkill = rfkill_alloc(wimax_dev->name, dev, RFKILL_TYPE_WIMAX,
+			      &wimax_rfkill_ops, wimax_dev);
+	if (rfkill == NULL)
+		goto error_rfkill_allocate;
+
+	d_printf(1, dev, "rfkill %p\n", rfkill);
+
+	wimax_dev->rfkill = rfkill;
+
+	rfkill_init_sw_state(rfkill, 1);
+	result = rfkill_register(wimax_dev->rfkill);
+	if (result < 0)
+		goto error_rfkill_register;
+
+	/* If there is no SW toggle op, SW RFKill is always on */
+	if (wimax_dev->op_rfkill_sw_toggle == NULL)
+		wimax_dev->rf_sw = WIMAX_RF_ON;
+
+	d_fnend(3, dev, "(wimax_dev %p) = 0\n", wimax_dev);
+	return 0;
+
+error_rfkill_register:
+	rfkill_destroy(wimax_dev->rfkill);
+error_rfkill_allocate:
+	d_fnend(3, dev, "(wimax_dev %p) = %d\n", wimax_dev, result);
+	return result;
+}
+
+
+/*
+ * Deregister a WiMAX device's RF Kill support
+ *
+ * Ick, we can't call rfkill_free() after rfkill_unregister()...oh
+ * well.
+ *
+ * WARNING: wimax_dev->mutex must be unlocked
+ */
+void wimax_rfkill_rm(struct wimax_dev *wimax_dev)
+{
+	struct device *dev = wimax_dev_to_dev(wimax_dev);
+	d_fnstart(3, dev, "(wimax_dev %p)\n", wimax_dev);
+	rfkill_unregister(wimax_dev->rfkill);
+	rfkill_destroy(wimax_dev->rfkill);
+	d_fnend(3, dev, "(wimax_dev %p)\n", wimax_dev);
+}
+
+
+/*
+ * Exporting to user space over generic netlink
+ *
+ * Parse the rfkill command from user space, return a combination
+ * value that describe the states of the different toggles.
+ *
+ * Only one attribute: the new state requested (on, off or no change,
+ * just query).
+ */
+
+int wimax_gnl_doit_rfkill(struct sk_buff *skb, struct genl_info *info)
+{
+	int result, ifindex;
+	struct wimax_dev *wimax_dev;
+	struct device *dev;
+	enum wimax_rf_state new_state;
+
+	d_fnstart(3, NULL, "(skb %p info %p)\n", skb, info);
+	result = -ENODEV;
+	if (info->attrs[WIMAX_GNL_RFKILL_IFIDX] == NULL) {
+		pr_err("WIMAX_GNL_OP_RFKILL: can't find IFIDX attribute\n");
+		goto error_no_wimax_dev;
+	}
+	ifindex = nla_get_u32(info->attrs[WIMAX_GNL_RFKILL_IFIDX]);
+	wimax_dev = wimax_dev_get_by_genl_info(info, ifindex);
+	if (wimax_dev == NULL)
+		goto error_no_wimax_dev;
+	dev = wimax_dev_to_dev(wimax_dev);
+	result = -EINVAL;
+	if (info->attrs[WIMAX_GNL_RFKILL_STATE] == NULL) {
+		dev_err(dev, "WIMAX_GNL_RFKILL: can't find RFKILL_STATE "
+			"attribute\n");
+		goto error_no_pid;
+	}
+	new_state = nla_get_u32(info->attrs[WIMAX_GNL_RFKILL_STATE]);
+
+	/* Execute the operation and send the result back to user space */
+	result = wimax_rfkill(wimax_dev, new_state);
+error_no_pid:
+	dev_put(wimax_dev->net_dev);
+error_no_wimax_dev:
+	d_fnend(3, NULL, "(skb %p info %p) = %d\n", skb, info, result);
+	return result;
+}