1 /*
2 * Intel Wireless WiMAX Connection 2400m
3 * Implement backend for the WiMAX stack rfkill support
4 *
5 *
6 * Copyright (C) 2007-2008 Intel Corporation <linux-wimax@intel.com>
7 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License version
11 * 2 as published by the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
21 * 02110-1301, USA.
22 *
23 *
24 * The WiMAX kernel stack integrates into RF-Kill and keeps the
25 * switches's status. We just need to:
26 *
27 * - report changes in the HW RF Kill switch [with
28 * wimax_rfkill_{sw,hw}_report(), which happens when we detect those
29 * indications coming through hardware reports]. We also do it on
30 * initialization to let the stack know the initial HW state.
31 *
32 * - implement indications from the stack to change the SW RF Kill
33 * switch (coming from sysfs, the wimax stack or user space).
34 */
35 #include "i2400m.h"
36 #include <linux/wimax/i2400m.h>
37 #include <linux/slab.h>
38
39
40
41 #define D_SUBMODULE rfkill
42 #include "debug-levels.h"
43
44 /*
45 * Return true if the i2400m radio is in the requested wimax_rf_state state
46 *
47 */
48 static
i2400m_radio_is(struct i2400m * i2400m,enum wimax_rf_state state)49 int i2400m_radio_is(struct i2400m *i2400m, enum wimax_rf_state state)
50 {
51 if (state == WIMAX_RF_OFF)
52 return i2400m->state == I2400M_SS_RF_OFF
53 || i2400m->state == I2400M_SS_RF_SHUTDOWN;
54 else if (state == WIMAX_RF_ON)
55 /* state == WIMAX_RF_ON */
56 return i2400m->state != I2400M_SS_RF_OFF
57 && i2400m->state != I2400M_SS_RF_SHUTDOWN;
58 else {
59 BUG();
60 return -EINVAL; /* shut gcc warnings on certain arches */
61 }
62 }
63
64
65 /*
66 * WiMAX stack operation: implement SW RFKill toggling
67 *
68 * @wimax_dev: device descriptor
69 * @skb: skb where the message has been received; skb->data is
70 * expected to point to the message payload.
71 * @genl_info: passed by the generic netlink layer
72 *
73 * Generic Netlink will call this function when a message is sent from
74 * userspace to change the software RF-Kill switch status.
75 *
76 * This function will set the device's software RF-Kill switch state to
77 * match what is requested.
78 *
79 * NOTE: the i2400m has a strict state machine; we can only set the
80 * RF-Kill switch when it is on, the HW RF-Kill is on and the
81 * device is initialized. So we ignore errors steaming from not
82 * being in the right state (-EILSEQ).
83 */
i2400m_op_rfkill_sw_toggle(struct wimax_dev * wimax_dev,enum wimax_rf_state state)84 int i2400m_op_rfkill_sw_toggle(struct wimax_dev *wimax_dev,
85 enum wimax_rf_state state)
86 {
87 int result;
88 struct i2400m *i2400m = wimax_dev_to_i2400m(wimax_dev);
89 struct device *dev = i2400m_dev(i2400m);
90 struct sk_buff *ack_skb;
91 struct {
92 struct i2400m_l3l4_hdr hdr;
93 struct i2400m_tlv_rf_operation sw_rf;
94 } __packed *cmd;
95 char strerr[32];
96
97 d_fnstart(4, dev, "(wimax_dev %p state %d)\n", wimax_dev, state);
98
99 result = -ENOMEM;
100 cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
101 if (cmd == NULL)
102 goto error_alloc;
103 cmd->hdr.type = cpu_to_le16(I2400M_MT_CMD_RF_CONTROL);
104 cmd->hdr.length = sizeof(cmd->sw_rf);
105 cmd->hdr.version = cpu_to_le16(I2400M_L3L4_VERSION);
106 cmd->sw_rf.hdr.type = cpu_to_le16(I2400M_TLV_RF_OPERATION);
107 cmd->sw_rf.hdr.length = cpu_to_le16(sizeof(cmd->sw_rf.status));
108 switch (state) {
109 case WIMAX_RF_OFF: /* RFKILL ON, radio OFF */
110 cmd->sw_rf.status = cpu_to_le32(2);
111 break;
112 case WIMAX_RF_ON: /* RFKILL OFF, radio ON */
113 cmd->sw_rf.status = cpu_to_le32(1);
114 break;
115 default:
116 BUG();
117 }
118
119 ack_skb = i2400m_msg_to_dev(i2400m, cmd, sizeof(*cmd));
120 result = PTR_ERR(ack_skb);
121 if (IS_ERR(ack_skb)) {
122 dev_err(dev, "Failed to issue 'RF Control' command: %d\n",
123 result);
124 goto error_msg_to_dev;
125 }
126 result = i2400m_msg_check_status(wimax_msg_data(ack_skb),
127 strerr, sizeof(strerr));
128 if (result < 0) {
129 dev_err(dev, "'RF Control' (0x%04x) command failed: %d - %s\n",
130 I2400M_MT_CMD_RF_CONTROL, result, strerr);
131 goto error_cmd;
132 }
133
134 /* Now we wait for the state to change to RADIO_OFF or RADIO_ON */
135 result = wait_event_timeout(
136 i2400m->state_wq, i2400m_radio_is(i2400m, state),
137 5 * HZ);
138 if (result == 0)
139 result = -ETIMEDOUT;
140 if (result < 0)
141 dev_err(dev, "Error waiting for device to toggle RF state: "
142 "%d\n", result);
143 result = 0;
144 error_cmd:
145 kfree_skb(ack_skb);
146 error_msg_to_dev:
147 error_alloc:
148 d_fnend(4, dev, "(wimax_dev %p state %d) = %d\n",
149 wimax_dev, state, result);
150 return result;
151 }
152
153
154 /*
155 * Inform the WiMAX stack of changes in the RF Kill switches reported
156 * by the device
157 *
158 * @i2400m: device descriptor
159 * @rfss: TLV for RF Switches status; already validated
160 *
161 * NOTE: the reports on RF switch status cannot be trusted
162 * or used until the device is in a state of RADIO_OFF
163 * or greater.
164 */
i2400m_report_tlv_rf_switches_status(struct i2400m * i2400m,const struct i2400m_tlv_rf_switches_status * rfss)165 void i2400m_report_tlv_rf_switches_status(
166 struct i2400m *i2400m,
167 const struct i2400m_tlv_rf_switches_status *rfss)
168 {
169 struct device *dev = i2400m_dev(i2400m);
170 enum i2400m_rf_switch_status hw, sw;
171 enum wimax_st wimax_state;
172
173 sw = le32_to_cpu(rfss->sw_rf_switch);
174 hw = le32_to_cpu(rfss->hw_rf_switch);
175
176 d_fnstart(3, dev, "(i2400m %p rfss %p [hw %u sw %u])\n",
177 i2400m, rfss, hw, sw);
178 /* We only process rw switch evens when the device has been
179 * fully initialized */
180 wimax_state = wimax_state_get(&i2400m->wimax_dev);
181 if (wimax_state < WIMAX_ST_RADIO_OFF) {
182 d_printf(3, dev, "ignoring RF switches report, state %u\n",
183 wimax_state);
184 goto out;
185 }
186 switch (sw) {
187 case I2400M_RF_SWITCH_ON: /* RF Kill disabled (radio on) */
188 wimax_report_rfkill_sw(&i2400m->wimax_dev, WIMAX_RF_ON);
189 break;
190 case I2400M_RF_SWITCH_OFF: /* RF Kill enabled (radio off) */
191 wimax_report_rfkill_sw(&i2400m->wimax_dev, WIMAX_RF_OFF);
192 break;
193 default:
194 dev_err(dev, "HW BUG? Unknown RF SW state 0x%x\n", sw);
195 }
196
197 switch (hw) {
198 case I2400M_RF_SWITCH_ON: /* RF Kill disabled (radio on) */
199 wimax_report_rfkill_hw(&i2400m->wimax_dev, WIMAX_RF_ON);
200 break;
201 case I2400M_RF_SWITCH_OFF: /* RF Kill enabled (radio off) */
202 wimax_report_rfkill_hw(&i2400m->wimax_dev, WIMAX_RF_OFF);
203 break;
204 default:
205 dev_err(dev, "HW BUG? Unknown RF HW state 0x%x\n", hw);
206 }
207 out:
208 d_fnend(3, dev, "(i2400m %p rfss %p [hw %u sw %u]) = void\n",
209 i2400m, rfss, hw, sw);
210 }
211