linux-stable/drivers/net/wimax/i2400m/op-rfkill.c
Inaky Perez-Gonzalez 98eb0f53e2 wimax: fix gcc warnings in sh4 when calling BUG()
SH4's BUG() seems to confuse the compiler as it is considered to
return; thus, some functions would trigger usage of uninitialized
variables or non-void functions returning void.

Work around by initializing/returning.

Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
2009-06-11 11:47:39 -07:00

209 lines
6.4 KiB
C

/*
* 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);
}