aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/net/wimax/i2400m/op-rfkill.c
blob: 43927b5d7ad6158a959b06f305e008b56bb306b5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
/*
 * Intel Wireless WiMAX Connection 2400m
 * Implement backend for the WiMAX stack rfkill support
 *
 *
 * Copyright (C) 2007-2008 Intel Corporation <linux-wimax@intel.com>
 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
 *
 * 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.
 *
 * 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.
 *
 *
 * The WiMAX kernel stack integrates into RF-Kill and keeps the
 * switches's status. We just need to:
 *
 * - report changes in the HW RF Kill switch [with
 *   wimax_rfkill_{sw,hw}_report(), which happens when we detect those
 *   indications coming through hardware reports]. We also do it on
 *   initialization to let the stack know the intial HW state.
 *
 * - implement indications from the stack to change the SW RF Kill
 *   switch (coming from sysfs, the wimax stack or user space).
 */
#include "i2400m.h"
#include <linux/wimax/i2400m.h>



#define D_SUBMODULE rfkill
#include "debug-levels.h"

/*
 * Return true if the i2400m radio is in the requested wimax_rf_state state
 *
 */
static
int i2400m_radio_is(struct i2400m *i2400m, enum wimax_rf_state state)
{
	if (state == WIMAX_RF_OFF)
		return i2400m->state == I2400M_SS_RF_OFF
			|| i2400m->state == I2400M_SS_RF_SHUTDOWN;
	else if (state == WIMAX_RF_ON)
		/* state == WIMAX_RF_ON */
		return i2400m->state != I2400M_SS_RF_OFF
			&& i2400m->state != I2400M_SS_RF_SHUTDOWN;
	else {
		BUG();
		return -EINVAL;	/* shut gcc warnings on certain arches */
	}
}


/*
 * WiMAX stack operation: implement SW RFKill toggling
 *
 * @wimax_dev: device descriptor
 * @skb: skb where the message has been received; skb->data is
 *       expected to point to the message payload.
 * @genl_info: passed by the generic netlink layer
 *
 * Generic Netlink will call this function when a message is sent from
 * userspace to change the software RF-Kill switch status.
 *
 * This function will set the device's sofware RF-Kill switch state to
 * match what is requested.
 *
 * NOTE: the i2400m has a strict state machine; we can only set the
 *       RF-Kill switch when it is on, the HW RF-Kill is on and the
 *       device is initialized. So we ignore errors steaming from not
 *       being in the right state (-EILSEQ).
 */
int i2400m_op_rfkill_sw_toggle(struct wimax_dev *wimax_dev,
			       enum wimax_rf_state state)
{
	int result;
	struct i2400m *i2400m = wimax_dev_to_i2400m(wimax_dev);
	struct device *dev = i2400m_dev(i2400m);
	struct sk_buff *ack_skb;
	struct {
		struct i2400m_l3l4_hdr hdr;
		struct i2400m_tlv_rf_operation sw_rf;
	} __attribute__((packed)) *cmd;
	char strerr[32];

	d_fnstart(4, dev, "(wimax_dev %p state %d)\n", wimax_dev, state);

	result = -ENOMEM;
	cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
	if (cmd == NULL)
		goto error_alloc;
	cmd->hdr.type = cpu_to_le16(I2400M_MT_CMD_RF_CONTROL);
	cmd->hdr.length = sizeof(cmd->sw_rf);
	cmd->hdr.version = cpu_to_le16(I2400M_L3L4_VERSION);
	cmd->sw_rf.hdr.type = cpu_to_le16(I2400M_TLV_RF_OPERATION);
	cmd->sw_rf.hdr.length = cpu_to_le16(sizeof(cmd->sw_rf.status));
	switch (state) {
	case WIMAX_RF_OFF:	/* RFKILL ON, radio OFF */
		cmd->sw_rf.status = cpu_to_le32(2);
		break;
	case WIMAX_RF_ON:	/* RFKILL OFF, radio ON */
		cmd->sw_rf.status = cpu_to_le32(1);
		break;
	default:
		BUG();
	}

	ack_skb = i2400m_msg_to_dev(i2400m, cmd, sizeof(*cmd));
	result = PTR_ERR(ack_skb);
	if (IS_ERR(ack_skb)) {
		dev_err(dev, "Failed to issue 'RF Control' command: %d\n",
			result);
		goto error_msg_to_dev;
	}
	result = i2400m_msg_check_status(wimax_msg_data(ack_skb),
					 strerr, sizeof(strerr));
	if (result < 0) {
		dev_err(dev, "'RF Control' (0x%04x) command failed: %d - %s\n",
			I2400M_MT_CMD_RF_CONTROL, result, strerr);
		goto error_cmd;
	}

	/* Now we wait for the state to change to RADIO_OFF or RADIO_ON */
	result = wait_event_timeout(
		i2400m->state_wq, i2400m_radio_is(i2400m, state),
		5 * HZ);
	if (result == 0)
		result = -ETIMEDOUT;
	if (result < 0)
		dev_err(dev, "Error waiting for device to toggle RF state: "
			"%d\n", result);
	result = 0;
error_cmd:
	kfree_skb(ack_skb);
error_msg_to_dev:
error_alloc:
	d_fnend(4, dev, "(wimax_dev %p state %d) = %d\n",
		wimax_dev, state, result);
	return result;
}


/*
 * Inform the WiMAX stack of changes in the RF Kill switches reported
 * by the device
 *
 * @i2400m: device descriptor
 * @rfss: TLV for RF Switches status; already validated
 *
 * NOTE: the reports on RF switch status cannot be trusted
 *       or used until the device is in a state of RADIO_OFF
 *       or greater.
 */
void i2400m_report_tlv_rf_switches_status(
	struct i2400m *i2400m,
	const struct i2400m_tlv_rf_switches_status *rfss)
{
	struct device *dev = i2400m_dev(i2400m);
	enum i2400m_rf_switch_status hw, sw;
	enum wimax_st wimax_state;

	sw = le32_to_cpu(rfss->sw_rf_switch);
	hw = le32_to_cpu(rfss->hw_rf_switch);

	d_fnstart(3, dev, "(i2400m %p rfss %p [hw %u sw %u])\n",
		  i2400m, rfss, hw, sw);
	/* We only process rw switch evens when the device has been
	 * fully initialized */
	wimax_state = wimax_state_get(&i2400m->wimax_dev);
	if (wimax_state < WIMAX_ST_RADIO_OFF) {
		d_printf(3, dev, "ignoring RF switches report, state %u\n",
			 wimax_state);
		goto out;
	}
	switch (sw) {
	case I2400M_RF_SWITCH_ON:	/* RF Kill disabled (radio on) */
		wimax_report_rfkill_sw(&i2400m->wimax_dev, WIMAX_RF_ON);
		break;
	case I2400M_RF_SWITCH_OFF:	/* RF Kill enabled (radio off) */
		wimax_report_rfkill_sw(&i2400m->wimax_dev, WIMAX_RF_OFF);
		break;
	default:
		dev_err(dev, "HW BUG? Unknown RF SW state 0x%x\n", sw);
	}

	switch (hw) {
	case I2400M_RF_SWITCH_ON:	/* RF Kill disabled (radio on) */
		wimax_report_rfkill_hw(&i2400m->wimax_dev, WIMAX_RF_ON);
		break;
	case I2400M_RF_SWITCH_OFF:	/* RF Kill enabled (radio off) */
		wimax_report_rfkill_hw(&i2400m->wimax_dev, WIMAX_RF_OFF);
		break;
	default:
		dev_err(dev, "HW BUG? Unknown RF HW state 0x%x\n", hw);
	}
out:
	d_fnend(3, dev, "(i2400m %p rfss %p [hw %u sw %u]) = void\n",
		i2400m, rfss, hw, sw);
}