Revert "dell-laptop: Remove rfkill code"

Without rfkill functionality in dell-laptop I have the following problems:
-If the hardware radio switch is set to disable the radio, then userspace
 will still think it can use wireless and bluetooth.
-The wwan / 3g modem cannot be soft blocked without the dell-laptop rfkill
 functionality

I know the rfkill functionality was removed from the dell-laptop driver because
it caused more problems then it fixed, and the blacklist for it was growing out
of control.

But in the thread discussing this Dell mentioned that they only QA the rfkill
acpi interface on Latitudes and indeed there have been no blacklist entries
for Latitudes. Therefor I would like to bring the rfkill functionality back
only for Latitudes. This patch is a straight-forward revert. The next patch
in this set will drop the blacklist and replace it with a Latitude check.

This reverts commit a6c2390c.

Conflicts:
	drivers/platform/x86/dell-laptop.c
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>

drivers/platform/x86/dell-laptop.c

@@ -21,6 +21,7 @@
 #include <linux/err.h>
 #include <linux/dmi.h>
 #include <linux/io.h>
+#include <linux/rfkill.h>
 #include <linux/power_supply.h>
 #include <linux/acpi.h>
 #include <linux/mm.h>
@@ -89,6 +90,9 @@ static struct platform_driver platform_driver = {
 
 static struct platform_device *platform_device;
 static struct backlight_device *dell_backlight_device;
+static struct rfkill *wifi_rfkill;
+static struct rfkill *bluetooth_rfkill;
+static struct rfkill *wwan_rfkill;
 
 static const struct dmi_system_id dell_device_table[] __initconst = {
 	{
@@ -115,6 +119,53 @@ static const struct dmi_system_id dell_device_table[] __initconst = {
 };
 MODULE_DEVICE_TABLE(dmi, dell_device_table);
 
+static struct dmi_system_id dell_blacklist[] = {
+	/* Supported by compal-laptop */
+	{
+		.ident = "Dell Mini 9",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 910"),
+		},
+	},
+	{
+		.ident = "Dell Mini 10",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 1010"),
+		},
+	},
+	{
+		.ident = "Dell Mini 10v",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 1011"),
+		},
+	},
+	{
+		.ident = "Dell Mini 1012",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 1012"),
+		},
+	},
+	{
+		.ident = "Dell Inspiron 11z",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 1110"),
+		},
+	},
+	{
+		.ident = "Dell Mini 12",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 1210"),
+		},
+	},
+	{}
+};
+
 static struct dmi_system_id dell_quirks[] = {
 	{
 		.callback = dmi_matched,
@@ -355,6 +406,94 @@ dell_send_request(struct calling_interface_buffer *buffer, int class,
 	return buffer;
 }
 
+/* Derived from information in DellWirelessCtl.cpp:
+   Class 17, select 11 is radio control. It returns an array of 32-bit values.
+
+   Input byte 0 = 0: Wireless information
+
+   result[0]: return code
+   result[1]:
+     Bit 0:      Hardware switch supported
+     Bit 1:      Wifi locator supported
+     Bit 2:      Wifi is supported
+     Bit 3:      Bluetooth is supported
+     Bit 4:      WWAN is supported
+     Bit 5:      Wireless keyboard supported
+     Bits 6-7:   Reserved
+     Bit 8:      Wifi is installed
+     Bit 9:      Bluetooth is installed
+     Bit 10:     WWAN is installed
+     Bits 11-15: Reserved
+     Bit 16:     Hardware switch is on
+     Bit 17:     Wifi is blocked
+     Bit 18:     Bluetooth is blocked
+     Bit 19:     WWAN is blocked
+     Bits 20-31: Reserved
+   result[2]: NVRAM size in bytes
+   result[3]: NVRAM format version number
+
+   Input byte 0 = 2: Wireless switch configuration
+   result[0]: return code
+   result[1]:
+     Bit 0:      Wifi controlled by switch
+     Bit 1:      Bluetooth controlled by switch
+     Bit 2:      WWAN controlled by switch
+     Bits 3-6:   Reserved
+     Bit 7:      Wireless switch config locked
+     Bit 8:      Wifi locator enabled
+     Bits 9-14:  Reserved
+     Bit 15:     Wifi locator setting locked
+     Bits 16-31: Reserved
+*/
+
+static int dell_rfkill_set(void *data, bool blocked)
+{
+	int disable = blocked ? 1 : 0;
+	unsigned long radio = (unsigned long)data;
+	int hwswitch_bit = (unsigned long)data - 1;
+	int ret = 0;
+
+	get_buffer();
+	dell_send_request(buffer, 17, 11);
+
+	/* If the hardware switch controls this radio, and the hardware
+	   switch is disabled, don't allow changing the software state */
+	if ((hwswitch_state & BIT(hwswitch_bit)) &&
+	    !(buffer->output[1] & BIT(16))) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	buffer->input[0] = (1 | (radio<<8) | (disable << 16));
+	dell_send_request(buffer, 17, 11);
+
+out:
+	release_buffer();
+	return ret;
+}
+
+static void dell_rfkill_query(struct rfkill *rfkill, void *data)
+{
+	int status;
+	int bit = (unsigned long)data + 16;
+	int hwswitch_bit = (unsigned long)data - 1;
+
+	get_buffer();
+	dell_send_request(buffer, 17, 11);
+	status = buffer->output[1];
+	release_buffer();
+
+	rfkill_set_sw_state(rfkill, !!(status & BIT(bit)));
+
+	if (hwswitch_state & (BIT(hwswitch_bit)))
+		rfkill_set_hw_state(rfkill, !(status & BIT(16)));
+}
+
+static const struct rfkill_ops dell_rfkill_ops = {
+	.set_block = dell_rfkill_set,
+	.query = dell_rfkill_query,
+};
+
 static struct dentry *dell_laptop_dir;
 
 static int dell_debugfs_show(struct seq_file *s, void *data)
@@ -424,6 +563,108 @@ static const struct file_operations dell_debugfs_fops = {
 	.release = single_release,
 };
 
+static void dell_update_rfkill(struct work_struct *ignored)
+{
+	if (wifi_rfkill)
+		dell_rfkill_query(wifi_rfkill, (void *)1);
+	if (bluetooth_rfkill)
+		dell_rfkill_query(bluetooth_rfkill, (void *)2);
+	if (wwan_rfkill)
+		dell_rfkill_query(wwan_rfkill, (void *)3);
+}
+static DECLARE_DELAYED_WORK(dell_rfkill_work, dell_update_rfkill);
+
+
+static int __init dell_setup_rfkill(void)
+{
+	int status;
+	int ret;
+
+	if (dmi_check_system(dell_blacklist)) {
+		pr_info("Blacklisted hardware detected - not enabling rfkill\n");
+		return 0;
+	}
+
+	get_buffer();
+	dell_send_request(buffer, 17, 11);
+	status = buffer->output[1];
+	buffer->input[0] = 0x2;
+	dell_send_request(buffer, 17, 11);
+	hwswitch_state = buffer->output[1];
+	release_buffer();
+
+	if ((status & (1<<2|1<<8)) == (1<<2|1<<8)) {
+		wifi_rfkill = rfkill_alloc("dell-wifi", &platform_device->dev,
+					   RFKILL_TYPE_WLAN,
+					   &dell_rfkill_ops, (void *) 1);
+		if (!wifi_rfkill) {
+			ret = -ENOMEM;
+			goto err_wifi;
+		}
+		ret = rfkill_register(wifi_rfkill);
+		if (ret)
+			goto err_wifi;
+	}
+
+	if ((status & (1<<3|1<<9)) == (1<<3|1<<9)) {
+		bluetooth_rfkill = rfkill_alloc("dell-bluetooth",
+						&platform_device->dev,
+						RFKILL_TYPE_BLUETOOTH,
+						&dell_rfkill_ops, (void *) 2);
+		if (!bluetooth_rfkill) {
+			ret = -ENOMEM;
+			goto err_bluetooth;
+		}
+		ret = rfkill_register(bluetooth_rfkill);
+		if (ret)
+			goto err_bluetooth;
+	}
+
+	if ((status & (1<<4|1<<10)) == (1<<4|1<<10)) {
+		wwan_rfkill = rfkill_alloc("dell-wwan",
+					   &platform_device->dev,
+					   RFKILL_TYPE_WWAN,
+					   &dell_rfkill_ops, (void *) 3);
+		if (!wwan_rfkill) {
+			ret = -ENOMEM;
+			goto err_wwan;
+		}
+		ret = rfkill_register(wwan_rfkill);
+		if (ret)
+			goto err_wwan;
+	}
+
+	return 0;
+err_wwan:
+	rfkill_destroy(wwan_rfkill);
+	if (bluetooth_rfkill)
+		rfkill_unregister(bluetooth_rfkill);
+err_bluetooth:
+	rfkill_destroy(bluetooth_rfkill);
+	if (wifi_rfkill)
+		rfkill_unregister(wifi_rfkill);
+err_wifi:
+	rfkill_destroy(wifi_rfkill);
+
+	return ret;
+}
+
+static void dell_cleanup_rfkill(void)
+{
+	if (wifi_rfkill) {
+		rfkill_unregister(wifi_rfkill);
+		rfkill_destroy(wifi_rfkill);
+	}
+	if (bluetooth_rfkill) {
+		rfkill_unregister(bluetooth_rfkill);
+		rfkill_destroy(bluetooth_rfkill);
+	}
+	if (wwan_rfkill) {
+		rfkill_unregister(wwan_rfkill);
+		rfkill_destroy(wwan_rfkill);
+	}
+}
+
 static int dell_send_intensity(struct backlight_device *bd)
 {
 	int ret = 0;
@@ -515,6 +756,30 @@ static void touchpad_led_exit(void)
 	led_classdev_unregister(&touchpad_led);
 }
 
+static bool dell_laptop_i8042_filter(unsigned char data, unsigned char str,
+			      struct serio *port)
+{
+	static bool extended;
+
+	if (str & 0x20)
+		return false;
+
+	if (unlikely(data == 0xe0)) {
+		extended = true;
+		return false;
+	} else if (unlikely(extended)) {
+		switch (data) {
+		case 0x8:
+			schedule_delayed_work(&dell_rfkill_work,
+					      round_jiffies_relative(HZ));
+			break;
+		}
+		extended = false;
+	}
+
+	return false;
+}
+
 static int __init dell_init(void)
 {
 	int max_intensity = 0;
@@ -557,10 +822,26 @@ static int __init dell_init(void)
 	}
 	buffer = page_address(bufferpage);
 
+	ret = dell_setup_rfkill();
+
+	if (ret) {
+		pr_warn("Unable to setup rfkill\n");
+		goto fail_rfkill;
+	}
+
+	ret = i8042_install_filter(dell_laptop_i8042_filter);
+	if (ret) {
+		pr_warn("Unable to install key filter\n");
+		goto fail_filter;
+	}
+
 	if (quirks && quirks->touchpad_led)
 		touchpad_led_init(&platform_device->dev);
 
 	dell_laptop_dir = debugfs_create_dir("dell_laptop", NULL);
+	if (dell_laptop_dir != NULL)
+		debugfs_create_file("rfkill", 0444, dell_laptop_dir, NULL,
+				    &dell_debugfs_fops);
 
 #ifdef CONFIG_ACPI
 	/* In the event of an ACPI backlight being available, don't
@@ -603,6 +884,11 @@ static int __init dell_init(void)
 	return 0;
 
 fail_backlight:
+	i8042_remove_filter(dell_laptop_i8042_filter);
+	cancel_delayed_work_sync(&dell_rfkill_work);
+fail_filter:
+	dell_cleanup_rfkill();
+fail_rfkill:
 	free_page((unsigned long)bufferpage);
 fail_buffer:
 	platform_device_del(platform_device);
@@ -620,7 +906,10 @@ static void __exit dell_exit(void)
 	debugfs_remove_recursive(dell_laptop_dir);
 	if (quirks && quirks->touchpad_led)
 		touchpad_led_exit();
+	i8042_remove_filter(dell_laptop_i8042_filter);
+	cancel_delayed_work_sync(&dell_rfkill_work);
 	backlight_device_unregister(dell_backlight_device);
+	dell_cleanup_rfkill();
 	if (platform_device) {
 		platform_device_unregister(platform_device);
 		platform_driver_unregister(&platform_driver);