[PATCH 4.4 39/99] rtlwifi: rtl8723be: Add antenna select module parameter

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Larry Finger <Larry.Finger@xxxxxxxxxxxx>

commit c18d8f5095715c56bb3cd9cba64242542632054b upstream.

A number of new laptops have been delivered with only a single antenna.
In principle, this is OK; however, a problem arises when the on-board
EEPROM is programmed to use the other antenna connection. The option
of opening the computer and moving the connector is not always possible
as it will void the warranty in some cases. In addition, this solution
breaks the Windows driver when the box dual boots Linux and Windows.

A fix involving a new module parameter has been developed.  This commit
adds the new parameter and implements the changes needed for the driver.

Signed-off-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/net/wireless/realtek/rtlwifi/rtl8723be/hw.c |    5 +++++
 drivers/net/wireless/realtek/rtlwifi/rtl8723be/sw.c |    3 +++
 drivers/net/wireless/realtek/rtlwifi/wifi.h         |    3 +++
 3 files changed, 11 insertions(+)

--- a/drivers/net/wireless/realtek/rtlwifi/rtl8723be/hw.c
+++ b/drivers/net/wireless/realtek/rtlwifi/rtl8723be/hw.c
@@ -2684,6 +2684,7 @@ void rtl8723be_read_bt_coexist_info_from
 					      bool auto_load_fail, u8 *hwinfo)
 {
 	struct rtl_priv *rtlpriv = rtl_priv(hw);
+	struct rtl_mod_params *mod_params = rtlpriv->cfg->mod_params;
 	u8 value;
 	u32 tmpu_32;
 
@@ -2702,6 +2703,10 @@ void rtl8723be_read_bt_coexist_info_from
 		rtlpriv->btcoexist.btc_info.ant_num = ANT_X2;
 	}
 
+	/* override ant_num / ant_path */
+	if (mod_params->ant_sel)
+		rtlpriv->btcoexist.btc_info.ant_num =
+			(mod_params->ant_sel == 1 ? ANT_X2 : ANT_X1);
 }
 
 void rtl8723be_bt_reg_init(struct ieee80211_hw *hw)
--- a/drivers/net/wireless/realtek/rtlwifi/rtl8723be/sw.c
+++ b/drivers/net/wireless/realtek/rtlwifi/rtl8723be/sw.c
@@ -273,6 +273,7 @@ static struct rtl_mod_params rtl8723be_m
 	.msi_support = false,
 	.disable_watchdog = false,
 	.debug = DBG_EMERG,
+	.ant_sel = 0,
 };
 
 static struct rtl_hal_cfg rtl8723be_hal_cfg = {
@@ -394,6 +395,7 @@ module_param_named(fwlps, rtl8723be_mod_
 module_param_named(msi, rtl8723be_mod_params.msi_support, bool, 0444);
 module_param_named(disable_watchdog, rtl8723be_mod_params.disable_watchdog,
 		   bool, 0444);
+module_param_named(ant_sel, rtl8723be_mod_params.ant_sel, int, 0444);
 MODULE_PARM_DESC(swenc, "Set to 1 for software crypto (default 0)\n");
 MODULE_PARM_DESC(ips, "Set to 0 to not use link power save (default 1)\n");
 MODULE_PARM_DESC(swlps, "Set to 1 to use SW control power save (default 0)\n");
@@ -402,6 +404,7 @@ MODULE_PARM_DESC(msi, "Set to 1 to use M
 MODULE_PARM_DESC(debug, "Set debug level (0-5) (default 0)");
 MODULE_PARM_DESC(disable_watchdog,
 		 "Set to 1 to disable the watchdog (default 0)\n");
+MODULE_PARM_DESC(ant_sel, "Set to 1 or 2 to force antenna number (default 0)\n");
 
 static SIMPLE_DEV_PM_OPS(rtlwifi_pm_ops, rtl_pci_suspend, rtl_pci_resume);
 
--- a/drivers/net/wireless/realtek/rtlwifi/wifi.h
+++ b/drivers/net/wireless/realtek/rtlwifi/wifi.h
@@ -2252,6 +2252,9 @@ struct rtl_mod_params {
 
 	/* default 0: 1 means do not disable interrupts */
 	bool int_clear;
+
+	/* select antenna */
+	int ant_sel;
 };
 
 struct rtl_hal_usbint_cfg {