rfkill: rewrite

This patch completely rewrites the rfkill core to address
the following deficiencies:

 * all rfkill drivers need to implement polling where necessary
   rather than having one central implementation

 * updating the rfkill state cannot be done from arbitrary
   contexts, forcing drivers to use schedule_work and requiring
   lots of code

 * rfkill drivers need to keep track of soft/hard blocked
   internally -- the core should do this

 * the rfkill API has many unexpected quirks, for example being
   asymmetric wrt. alloc/free and register/unregister

 * rfkill can call back into a driver from within a function the
   driver called -- this is prone to deadlocks and generally
   should be avoided

 * rfkill-input pointlessly is a separate module

 * drivers need to #ifdef rfkill functions (unless they want to
   depend on or select RFKILL) -- rfkill should provide inlines
   that do nothing if it isn't compiled in

 * the rfkill structure is not opaque -- drivers need to initialise
   it correctly (lots of sanity checking code required) -- instead
   force drivers to pass the right variables to rfkill_alloc()

 * the documentation is hard to read because it always assumes the
   reader is completely clueless and contains way TOO MANY CAPS

 * the rfkill code needlessly uses a lot of locks and atomic
   operations in locked sections

 * fix LED trigger to actually change the LED when the radio state
   changes -- this wasn't done before

Tested-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> [thinkpad]
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 71 insertions, 120 deletions

diff --git a/drivers/platform/x86/sony-laptop.c b/drivers/platform/x86/sony-laptop.c
index f1963b05175b..aec0b27fd774 100644
--- a/drivers/platform/x86/sony-laptop.c
+++ b/drivers/platform/x86/sony-laptop.c
@@ -128,11 +128,11 @@ enum sony_nc_rfkill {
 	SONY_BLUETOOTH,
 	SONY_WWAN,
 	SONY_WIMAX,
-	SONY_RFKILL_MAX,
+	N_SONY_RFKILL,
 };
 
-static struct rfkill *sony_rfkill_devices[SONY_RFKILL_MAX];
-static int sony_rfkill_address[SONY_RFKILL_MAX] = {0x300, 0x500, 0x700, 0x900};
+static struct rfkill *sony_rfkill_devices[N_SONY_RFKILL];
+static int sony_rfkill_address[N_SONY_RFKILL] = {0x300, 0x500, 0x700, 0x900};
 static void sony_nc_rfkill_update(void);
 
 /*********** Input Devices ***********/
@@ -1051,147 +1051,98 @@ static void sony_nc_rfkill_cleanup(void)
 {
 	int i;
 
-	for (i = 0; i < SONY_RFKILL_MAX; i++) {
-		if (sony_rfkill_devices[i])
+	for (i = 0; i < N_SONY_RFKILL; i++) {
+		if (sony_rfkill_devices[i]) {
 			rfkill_unregister(sony_rfkill_devices[i]);
+			rfkill_destroy(sony_rfkill_devices[i]);
+		}
 	}
 }
 
-static int sony_nc_rfkill_get(void *data, enum rfkill_state *state)
-{
-	int result;
-	int argument = sony_rfkill_address[(long) data];
-
-	sony_call_snc_handle(0x124, 0x200, &result);
-	if (result & 0x1) {
-		sony_call_snc_handle(0x124, argument, &result);
-		if (result & 0xf)
-			*state = RFKILL_STATE_UNBLOCKED;
-		else
-			*state = RFKILL_STATE_SOFT_BLOCKED;
-	} else {
-		*state = RFKILL_STATE_HARD_BLOCKED;
-	}
-
-	return 0;
-}
-
-static int sony_nc_rfkill_set(void *data, enum rfkill_state state)
+static int sony_nc_rfkill_set(void *data, bool blocked)
 {
 	int result;
 	int argument = sony_rfkill_address[(long) data] + 0x100;
 
-	if (state == RFKILL_STATE_UNBLOCKED)
+	if (!blocked)
 		argument |= 0xff0000;
 
 	return sony_call_snc_handle(0x124, argument, &result);
 }
 
-static int sony_nc_setup_wifi_rfkill(struct acpi_device *device)
-{
-	int err = 0;
-	struct rfkill *sony_wifi_rfkill;
-
-	sony_wifi_rfkill = rfkill_allocate(&device->dev, RFKILL_TYPE_WLAN);
-	if (!sony_wifi_rfkill)
-		return -1;
-	sony_wifi_rfkill->name = "sony-wifi";
-	sony_wifi_rfkill->toggle_radio = sony_nc_rfkill_set;
-	sony_wifi_rfkill->get_state = sony_nc_rfkill_get;
-	sony_wifi_rfkill->data = (void *)SONY_WIFI;
-	err = rfkill_register(sony_wifi_rfkill);
-	if (err)
-		rfkill_free(sony_wifi_rfkill);
-	else {
-		sony_rfkill_devices[SONY_WIFI] = sony_wifi_rfkill;
-		sony_nc_rfkill_set(sony_wifi_rfkill->data,
-				RFKILL_STATE_UNBLOCKED);
-	}
-	return err;
-}
+static const struct rfkill_ops sony_rfkill_ops = {
+	.set_block = sony_nc_rfkill_set,
+};
 
-static int sony_nc_setup_bluetooth_rfkill(struct acpi_device *device)
+static int sony_nc_setup_rfkill(struct acpi_device *device,
+				enum sony_nc_rfkill nc_type)
 {
 	int err = 0;
-	struct rfkill *sony_bluetooth_rfkill;
-
-	sony_bluetooth_rfkill = rfkill_allocate(&device->dev,
-						RFKILL_TYPE_BLUETOOTH);
-	if (!sony_bluetooth_rfkill)
-		return -1;
-	sony_bluetooth_rfkill->name = "sony-bluetooth";
-	sony_bluetooth_rfkill->toggle_radio = sony_nc_rfkill_set;
-	sony_bluetooth_rfkill->get_state = sony_nc_rfkill_get;
-	sony_bluetooth_rfkill->data = (void *)SONY_BLUETOOTH;
-	err = rfkill_register(sony_bluetooth_rfkill);
-	if (err)
-		rfkill_free(sony_bluetooth_rfkill);
-	else {
-		sony_rfkill_devices[SONY_BLUETOOTH] = sony_bluetooth_rfkill;
-		sony_nc_rfkill_set(sony_bluetooth_rfkill->data,
-				RFKILL_STATE_UNBLOCKED);
+	struct rfkill *rfk;
+	enum rfkill_type type;
+	const char *name;
+
+	switch (nc_type) {
+	case SONY_WIFI:
+		type = RFKILL_TYPE_WLAN;
+		name = "sony-wifi";
+		break;
+	case SONY_BLUETOOTH:
+		type = RFKILL_TYPE_BLUETOOTH;
+		name = "sony-bluetooth";
+		break;
+	case SONY_WWAN:
+		type = RFKILL_TYPE_WWAN;
+		name = "sony-wwan";
+		break;
+	case SONY_WIMAX:
+		type = RFKILL_TYPE_WIMAX;
+		name = "sony-wimax";
+		break;
+	default:
+		return -EINVAL;
 	}
-	return err;
-}
 
-static int sony_nc_setup_wwan_rfkill(struct acpi_device *device)
-{
-	int err = 0;
-	struct rfkill *sony_wwan_rfkill;
+	rfk = rfkill_alloc(name, &device->dev, type,
+			   &sony_rfkill_ops, (void *)nc_type);
+	if (!rfk)
+		return -ENOMEM;
 
-	sony_wwan_rfkill = rfkill_allocate(&device->dev, RFKILL_TYPE_WWAN);
-	if (!sony_wwan_rfkill)
-		return -1;
-	sony_wwan_rfkill->name = "sony-wwan";
-	sony_wwan_rfkill->toggle_radio = sony_nc_rfkill_set;
-	sony_wwan_rfkill->get_state = sony_nc_rfkill_get;
-	sony_wwan_rfkill->data = (void *)SONY_WWAN;
-	err = rfkill_register(sony_wwan_rfkill);
-	if (err)
-		rfkill_free(sony_wwan_rfkill);
-	else {
-		sony_rfkill_devices[SONY_WWAN] = sony_wwan_rfkill;
-		sony_nc_rfkill_set(sony_wwan_rfkill->data,
-				RFKILL_STATE_UNBLOCKED);
+	err = rfkill_register(rfk);
+	if (err) {
+		rfkill_destroy(rfk);
+		return err;
 	}
+	sony_rfkill_devices[nc_type] = rfk;
+	sony_nc_rfkill_set((void *)nc_type, false);
 	return err;
 }
 
-static int sony_nc_setup_wimax_rfkill(struct acpi_device *device)
+static void sony_nc_rfkill_update()
 {
-	int err = 0;
-	struct rfkill *sony_wimax_rfkill;
+	enum sony_nc_rfkill i;
+	int result;
+	bool hwblock;
 
-	sony_wimax_rfkill = rfkill_allocate(&device->dev, RFKILL_TYPE_WIMAX);
-	if (!sony_wimax_rfkill)
-		return -1;
-	sony_wimax_rfkill->name = "sony-wimax";
-	sony_wimax_rfkill->toggle_radio = sony_nc_rfkill_set;
-	sony_wimax_rfkill->get_state = sony_nc_rfkill_get;
-	sony_wimax_rfkill->data = (void *)SONY_WIMAX;
-	err = rfkill_register(sony_wimax_rfkill);
-	if (err)
-		rfkill_free(sony_wimax_rfkill);
-	else {
-		sony_rfkill_devices[SONY_WIMAX] = sony_wimax_rfkill;
-		sony_nc_rfkill_set(sony_wimax_rfkill->data,
-				RFKILL_STATE_UNBLOCKED);
-	}
-	return err;
-}
+	sony_call_snc_handle(0x124, 0x200, &result);
+	hwblock = !(result & 0x1);
 
-static void sony_nc_rfkill_update()
-{
-	int i;
-	enum rfkill_state state;
+	for (i = 0; i < N_SONY_RFKILL; i++) {
+		int argument = sony_rfkill_address[i];
 
-	for (i = 0; i < SONY_RFKILL_MAX; i++) {
-		if (sony_rfkill_devices[i]) {
-			sony_rfkill_devices[i]->
-				get_state(sony_rfkill_devices[i]->data,
-					  &state);
-			rfkill_force_state(sony_rfkill_devices[i], state);
+		if (!sony_rfkill_devices[i])
+			continue;
+
+		if (hwblock) {
+			if (rfkill_set_hw_state(sony_rfkill_devices[i], true))
+				sony_nc_rfkill_set(sony_rfkill_devices[i],
+						   true);
+			continue;
 		}
+
+		sony_call_snc_handle(0x124, argument, &result);
+		rfkill_set_states(sony_rfkill_devices[i],
+				  !(result & 0xf), false);
 	}
 }
 
@@ -1210,13 +1161,13 @@ static int sony_nc_rfkill_setup(struct acpi_device *device)
 	}
 
 	if (result & 0x1)
-		sony_nc_setup_wifi_rfkill(device);
+		sony_nc_setup_rfkill(device, SONY_WIFI);
 	if (result & 0x2)
-		sony_nc_setup_bluetooth_rfkill(device);
+		sony_nc_setup_rfkill(device, SONY_BLUETOOTH);
 	if (result & 0x1c)
-		sony_nc_setup_wwan_rfkill(device);
+		sony_nc_setup_rfkill(device, SONY_WWAN);
 	if (result & 0x20)
-		sony_nc_setup_wimax_rfkill(device);
+		sony_nc_setup_rfkill(device, SONY_WIMAX);
 
 	return 0;
 }