rtlwifi: Convert to asynchronous firmware load

This patch addresses a kernel bugzilla report and two recent mail threads.

The kernel bugzilla report is https://bugzilla.kernel.org/show_bug.cgi?id=42632,
which reports a udev timeout on boot.

The first mail thread, which was on LKML (http://lkml.indiana.edu/hypermail/
linux/kernel/1112.3/00965.html) was for a WARNING that occurs after a
suspend/resume cycle for rtl8192cu.

The scond mail thread (http://marc.info/?l=linux-wireless&m=132655490826766&w=2)
concerned changes in udev that break drivers that delay while firmware is loaded
on modprobe.

This patch converts all rtlwifi-based drivers to use the asynchronous firmware
loading mechanism. Drivers rtl8192ce, rtl8192cu and rtl8192de share a common
callback routine. Driver rtl8192se needs different handling of the firmware,
thus it has its own code.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/rtlwifi/base.c

@@ -410,6 +410,7 @@ void rtl_init_rfkill(struct ieee80211_hw *hw)
 
 	wiphy_rfkill_start_polling(hw->wiphy);
 }
+EXPORT_SYMBOL(rtl_init_rfkill);
 
 void rtl_deinit_rfkill(struct ieee80211_hw *hw)
 {

drivers/net/wireless/rtlwifi/core.c

@@ -31,8 +31,50 @@
 #include "core.h"
 #include "cam.h"
 #include "base.h"
+#include "pci.h"
 #include "ps.h"
 
+#include <linux/export.h>
+
+void rtl_fw_cb(const struct firmware *firmware, void *context)
+{
+	struct ieee80211_hw *hw = context;
+	struct rtl_priv *rtlpriv = rtl_priv(hw);
+	int err;
+
+	RT_TRACE(rtlpriv, COMP_ERR, DBG_LOUD,
+			 "Firmware callback routine entered!\n");
+	complete(&rtlpriv->firmware_loading_complete);
+	if (!firmware) {
+		pr_err("Firmware %s not available\n", rtlpriv->cfg->fw_name);
+		rtlpriv->max_fw_size = 0;
+		return;
+	}
+	if (firmware->size > rtlpriv->max_fw_size) {
+		RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG,
+			 "Firmware is too big!\n");
+		release_firmware(firmware);
+		return;
+	}
+	memcpy(rtlpriv->rtlhal.pfirmware, firmware->data, firmware->size);
+	rtlpriv->rtlhal.fwsize = firmware->size;
+	release_firmware(firmware);
+
+	err = ieee80211_register_hw(hw);
+	if (err) {
+		RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG,
+			 "Can't register mac80211 hw\n");
+		return;
+	} else {
+		rtlpriv->mac80211.mac80211_registered = 1;
+	}
+	set_bit(RTL_STATUS_INTERFACE_START, &rtlpriv->status);
+
+	/*init rfkill */
+	rtl_init_rfkill(hw);
+}
+EXPORT_SYMBOL(rtl_fw_cb);
+
 /*mutex for start & stop is must here. */
 static int rtl_op_start(struct ieee80211_hw *hw)
 {
@@ -254,10 +296,12 @@ static int rtl_op_config(struct ieee80211_hw *hw, u32 changed)
 			 * because that will cause nullfunc send by mac80211
 			 * fail, and cause pkt loss, we have tested that 5mA
 			 * is worked very well */
-			if (!rtlpriv->psc.multi_buffered)
+			if (!rtlpriv->psc.multi_buffered) {
 				queue_delayed_work(rtlpriv->works.rtl_wq,
 						&rtlpriv->works.ps_work,
 						MSECS(5));
+				pr_info("In section\n");
+			}
 		} else {
 			rtl_swlps_rf_awake(hw);
 			rtlpriv->psc.sw_ps_enabled = false;

drivers/net/wireless/rtlwifi/core.h

@@ -40,4 +40,6 @@
 #define RTL_SUPPORTED_CTRL_FILTER	0xFF
 
 extern const struct ieee80211_ops rtl_ops;
+void rtl_fw_cb(const struct firmware *firmware, void *context);
+
 #endif

drivers/net/wireless/rtlwifi/pci.c

@@ -1565,6 +1565,9 @@ static void rtl_pci_stop(struct ieee80211_hw *hw)
 
 	rtlpci->driver_is_goingto_unload = true;
 	rtlpriv->cfg->ops->hw_disable(hw);
+	/* some things are not needed if firmware not available */
+	if (!rtlpriv->max_fw_size)
+		return;
 	rtlpriv->cfg->ops->led_control(hw, LED_CTL_POWER_OFF);
 
 	spin_lock_irqsave(&rtlpriv->locks.rf_ps_lock, flags);
@@ -1779,6 +1782,7 @@ int __devinit rtl_pci_probe(struct pci_dev *pdev,
 	rtlpriv = hw->priv;
 	pcipriv = (void *)rtlpriv->priv;
 	pcipriv->dev.pdev = pdev;
+	init_completion(&rtlpriv->firmware_loading_complete);
 
 	/* init cfg & intf_ops */
 	rtlpriv->rtlhal.interface = INTF_PCI;
@@ -1799,7 +1803,7 @@ int __devinit rtl_pci_probe(struct pci_dev *pdev,
 	err = pci_request_regions(pdev, KBUILD_MODNAME);
 	if (err) {
 		RT_ASSERT(false, "Can't obtain PCI resources\n");
-		return err;
+		goto fail2;
 	}
 
 	pmem_start = pci_resource_start(pdev, rtlpriv->cfg->bar_id);
@@ -1862,25 +1866,13 @@ int __devinit rtl_pci_probe(struct pci_dev *pdev,
 		goto fail3;
 	}
 
-	err = ieee80211_register_hw(hw);
-	if (err) {
-		RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG,
-			 "Can't register mac80211 hw\n");
-		goto fail3;
-	} else {
-		rtlpriv->mac80211.mac80211_registered = 1;
-	}
-
 	err = sysfs_create_group(&pdev->dev.kobj, &rtl_attribute_group);
 	if (err) {
 		RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG,
 			 "failed to create sysfs device attributes\n");
 		goto fail3;
 	}
 
-	/*init rfkill */
-	rtl_init_rfkill(hw);
-
 	rtlpci = rtl_pcidev(pcipriv);
 	err = request_irq(rtlpci->pdev->irq, &_rtl_pci_interrupt,
 			  IRQF_SHARED, KBUILD_MODNAME, hw);
@@ -1889,24 +1881,22 @@ int __devinit rtl_pci_probe(struct pci_dev *pdev,
 			 "%s: failed to register IRQ handler\n",
 			 wiphy_name(hw->wiphy));
 		goto fail3;
-	} else {
-		rtlpci->irq_alloc = 1;
 	}
+	rtlpci->irq_alloc = 1;
 
-	set_bit(RTL_STATUS_INTERFACE_START, &rtlpriv->status);
 	return 0;
 
 fail3:
 	pci_set_drvdata(pdev, NULL);
 	rtl_deinit_core(hw);
 	_rtl_pci_io_handler_release(hw);
-	ieee80211_free_hw(hw);
 
 	if (rtlpriv->io.pci_mem_start != 0)
 		pci_iounmap(pdev, (void __iomem *)rtlpriv->io.pci_mem_start);
 
 fail2:
 	pci_release_regions(pdev);
+	complete(&rtlpriv->firmware_loading_complete);
 
 fail1:
 
@@ -1925,6 +1915,8 @@ void rtl_pci_disconnect(struct pci_dev *pdev)
 	struct rtl_pci *rtlpci = rtl_pcidev(pcipriv);
 	struct rtl_mac *rtlmac = rtl_mac(rtlpriv);
 
+	/* just in case driver is removed before firmware callback */
+	wait_for_completion(&rtlpriv->firmware_loading_complete);
 	clear_bit(RTL_STATUS_INTERFACE_START, &rtlpriv->status);
 
 	sysfs_remove_group(&pdev->dev.kobj, &rtl_attribute_group);

drivers/net/wireless/rtlwifi/pci.h

@@ -239,7 +239,6 @@ int __devinit rtl_pci_probe(struct pci_dev *pdev,
 void rtl_pci_disconnect(struct pci_dev *pdev);
 int rtl_pci_suspend(struct device *dev);
 int rtl_pci_resume(struct device *dev);
-
 static inline u8 pci_read8_sync(struct rtl_priv *rtlpriv, u32 addr)
 {
 	return readb((u8 __iomem *) rtlpriv->io.pci_mem_start + addr);

drivers/net/wireless/rtlwifi/ps.c

@@ -47,7 +47,8 @@ bool rtl_ps_enable_nic(struct ieee80211_hw *hw)
 			 "Driver is already down!\n");
 
 	/*<2> Enable Adapter */
-	rtlpriv->cfg->ops->hw_init(hw);
+	if (rtlpriv->cfg->ops->hw_init(hw))
+		return 1;
 	RT_CLEAR_PS_LEVEL(ppsc, RT_RF_OFF_LEVL_HALT_NIC);
 
 	/*<3> Enable Interrupt */

drivers/net/wireless/rtlwifi/rtl8192c/fw_common.c

@@ -257,10 +257,9 @@ int rtl92c_download_fw(struct ieee80211_hw *hw)
 	u32 fwsize;
 	enum version_8192c version = rtlhal->version;
 
-	if (!rtlhal->pfirmware)
+	if (rtlpriv->max_fw_size == 0 || !rtlhal->pfirmware)
 		return 1;
 
-	pr_info("Loading firmware file %s\n", rtlpriv->cfg->fw_name);
 	pfwheader = (struct rtl92c_firmware_header *)rtlhal->pfirmware;
 	pfwdata = (u8 *) rtlhal->pfirmware;
 	fwsize = rtlhal->fwsize;
@@ -512,15 +511,8 @@ static void _rtl92c_fill_h2c_command(struct ieee80211_hw *hw,
 void rtl92c_fill_h2c_cmd(struct ieee80211_hw *hw,
 			 u8 element_id, u32 cmd_len, u8 *p_cmdbuffer)
 {
-	struct rtl_hal *rtlhal = rtl_hal(rtl_priv(hw));
 	u32 tmp_cmdbuf[2];
 
-	if (rtlhal->fw_ready == false) {
-		RT_ASSERT(false,
-			  "return H2C cmd because of Fw download fail!!!\n");
-		return;
-	}
-
 	memset(tmp_cmdbuf, 0, 8);
 	memcpy(tmp_cmdbuf, p_cmdbuffer, cmd_len);
 	_rtl92c_fill_h2c_command(hw, element_id, cmd_len, (u8 *)&tmp_cmdbuf);

drivers/net/wireless/rtlwifi/rtl8192ce/hw.c

@@ -917,10 +917,7 @@ int rtl92ce_hw_init(struct ieee80211_hw *hw)
 		RT_TRACE(rtlpriv, COMP_ERR, DBG_WARNING,
 			 "Failed to download FW. Init HW without FW now..\n");
 		err = 1;
-		rtlhal->fw_ready = false;
 		return err;
-	} else {
-		rtlhal->fw_ready = true;
 	}
 
 	rtlhal->last_hmeboxnum = 0;
@@ -1193,7 +1190,6 @@ static void _rtl92ce_poweroff_adapter(struct ieee80211_hw *hw)
 {
 	struct rtl_priv *rtlpriv = rtl_priv(hw);
 	struct rtl_pci_priv *rtlpcipriv = rtl_pcipriv(hw);
-	struct rtl_hal *rtlhal = rtl_hal(rtl_priv(hw));
 	u8 u1b_tmp;
 	u32 u4b_tmp;
 
@@ -1204,7 +1200,7 @@ static void _rtl92ce_poweroff_adapter(struct ieee80211_hw *hw)
 	rtl_write_byte(rtlpriv, REG_APSD_CTRL, 0x40);
 	rtl_write_byte(rtlpriv, REG_SYS_FUNC_EN, 0xE2);
 	rtl_write_byte(rtlpriv, REG_SYS_FUNC_EN, 0xE0);
-	if ((rtl_read_byte(rtlpriv, REG_MCUFWDL) & BIT(7)) && rtlhal->fw_ready)
+	if (rtl_read_byte(rtlpriv, REG_MCUFWDL) & BIT(7))
 		rtl92c_firmware_selfreset(hw);
 	rtl_write_byte(rtlpriv, REG_SYS_FUNC_EN + 1, 0x51);
 	rtl_write_byte(rtlpriv, REG_MCUFWDL, 0x00);

drivers/net/wireless/rtlwifi/rtl8192ce/sw.c

@@ -91,9 +91,7 @@ int rtl92c_init_sw_vars(struct ieee80211_hw *hw)
 	int err;
 	struct rtl_priv *rtlpriv = rtl_priv(hw);
 	struct rtl_pci *rtlpci = rtl_pcidev(rtl_pcipriv(hw));
-	const struct firmware *firmware;
 	struct rtl_hal *rtlhal = rtl_hal(rtl_priv(hw));
-	char *fw_name = NULL;
 
 	rtl8192ce_bt_reg_init(hw);
 
@@ -165,26 +163,20 @@ int rtl92c_init_sw_vars(struct ieee80211_hw *hw)
 	/* request fw */
 	if (IS_VENDOR_UMC_A_CUT(rtlhal->version) &&
 	    !IS_92C_SERIAL(rtlhal->version))
-		fw_name = "rtlwifi/rtl8192cfwU.bin";
+		rtlpriv->cfg->fw_name = "rtlwifi/rtl8192cfwU.bin";
 	else if (IS_81xxC_VENDOR_UMC_B_CUT(rtlhal->version))
-		fw_name = "rtlwifi/rtl8192cfwU_B.bin";
-	else
-		fw_name = rtlpriv->cfg->fw_name;
-	err = request_firmware(&firmware, fw_name, rtlpriv->io.dev);
+		rtlpriv->cfg->fw_name = "rtlwifi/rtl8192cfwU_B.bin";
+
+	rtlpriv->max_fw_size = 0x4000;
+	pr_info("Using firmware %s\n", rtlpriv->cfg->fw_name);
+	err = request_firmware_nowait(THIS_MODULE, 1, rtlpriv->cfg->fw_name,
+				      rtlpriv->io.dev, GFP_KERNEL, hw,
+				      rtl_fw_cb);
 	if (err) {
 		RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG,
 			 "Failed to request firmware!\n");
 		return 1;
 	}
-	if (firmware->size > 0x4000) {
-		RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG,
-			 "Firmware is too big!\n");
-		release_firmware(firmware);
-		return 1;
-	}
-	memcpy(rtlpriv->rtlhal.pfirmware, firmware->data, firmware->size);
-	rtlpriv->rtlhal.fwsize = firmware->size;
-	release_firmware(firmware);
 
 	return 0;
 }

drivers/net/wireless/rtlwifi/rtl8192cu/hw.c

@@ -997,10 +997,7 @@ int rtl92cu_hw_init(struct ieee80211_hw *hw)
 		RT_TRACE(rtlpriv, COMP_ERR, DBG_WARNING,
 			 "Failed to download FW. Init HW without FW now..\n");
 		err = 1;
-		rtlhal->fw_ready = false;
 		return err;
-	} else {
-		rtlhal->fw_ready = true;
 	}
 	rtlhal->last_hmeboxnum = 0; /* h2c */
 	_rtl92cu_phy_param_tab_init(hw);
@@ -1094,23 +1091,21 @@ static void  _ResetDigitalProcedure1(struct ieee80211_hw *hw, bool bWithoutHWSM)
 		if (rtl_read_byte(rtlpriv, REG_MCUFWDL) & BIT(1)) {
 			/* reset MCU ready status */
 			rtl_write_byte(rtlpriv, REG_MCUFWDL, 0);
-			if (rtlhal->fw_ready) {
-				/* 8051 reset by self */
-				rtl_write_byte(rtlpriv, REG_HMETFR+3, 0x20);
-				while ((retry_cnts++ < 100) &&
-				       (FEN_CPUEN & rtl_read_word(rtlpriv,
-				       REG_SYS_FUNC_EN))) {
-					udelay(50);
-				}
-				if (retry_cnts >= 100) {
-					RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG,
-						 "#####=> 8051 reset failed!.........................\n");
-					/* if 8051 reset fail, reset MAC. */
-					rtl_write_byte(rtlpriv,
-						       REG_SYS_FUNC_EN + 1,
-						       0x50);
-					udelay(100);
-				}
+			/* 8051 reset by self */
+			rtl_write_byte(rtlpriv, REG_HMETFR+3, 0x20);
+			while ((retry_cnts++ < 100) &&
+			       (FEN_CPUEN & rtl_read_word(rtlpriv,
+			       REG_SYS_FUNC_EN))) {
+				udelay(50);
+			}
+			if (retry_cnts >= 100) {
+				RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG,
+					 "#####=> 8051 reset failed!.........................\n");
+				/* if 8051 reset fail, reset MAC. */
+				rtl_write_byte(rtlpriv,
+					       REG_SYS_FUNC_EN + 1,
+					       0x50);
+				udelay(100);
 			}
 		}
 		/* Reset MAC and Enable 8051 */

drivers/net/wireless/rtlwifi/rtl8192cu/sw.c

@@ -53,37 +53,28 @@ MODULE_FIRMWARE("rtlwifi/rtl8192cufw.bin");
 static int rtl92cu_init_sw_vars(struct ieee80211_hw *hw)
 {
 	struct rtl_priv *rtlpriv = rtl_priv(hw);
-	const struct firmware *firmware;
 	int err;
 
 	rtlpriv->dm.dm_initialgain_enable = true;
 	rtlpriv->dm.dm_flag = 0;
 	rtlpriv->dm.disable_framebursting = false;
 	rtlpriv->dm.thermalvalue = 0;
 	rtlpriv->dbg.global_debuglevel = rtlpriv->cfg->mod_params->debug;
-	rtlpriv->rtlhal.pfirmware = vmalloc(0x4000);
+
+	/* for firmware buf */
+	rtlpriv->rtlhal.pfirmware = vzalloc(0x4000);
 	if (!rtlpriv->rtlhal.pfirmware) {
 		RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG,
 			 "Can't alloc buffer for fw\n");
 		return 1;
 	}
-	/* request fw */
-	err = request_firmware(&firmware, rtlpriv->cfg->fw_name,
-			rtlpriv->io.dev);
-	if (err) {
-		RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG,
-			 "Failed to request firmware!\n");
-		return 1;
-	}
-	if (firmware->size > 0x4000) {
-		RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG,
-			 "Firmware is too big!\n");
-		release_firmware(firmware);
-		return 1;
-	}
-	memcpy(rtlpriv->rtlhal.pfirmware, firmware->data, firmware->size);
-	rtlpriv->rtlhal.fwsize = firmware->size;
-	release_firmware(firmware);
+
+	pr_info("Loading firmware %s\n", rtlpriv->cfg->fw_name);
+	rtlpriv->max_fw_size = 0x4000;
+	err = request_firmware_nowait(THIS_MODULE, 1,
+				      rtlpriv->cfg->fw_name, rtlpriv->io.dev,
+				      GFP_KERNEL, hw, rtl_fw_cb);
+
 
 	return 0;
 }