iwlwifi: mvm: Add device wide power command

FW starts using legacy power table command (0x77) for device wide power
settings. Currently this command contains only option flags field.
It can configure the following: CAM (Continuous Active Mode) and
POWER_SAVE_ENABLE debug option. Send this command when firmware is
loaded - D0 and D3.
Note: Setting this command is important to avoid unwanted FW behavior.
It particularly fixes a bug when a device does not drop to low power
after disassociation from AP.

Signed-off-by: Alexander Bondar <alexander.bondar@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

drivers/net/wireless/iwlwifi/iwl-fw.h

@@ -88,6 +88,8 @@
  * @IWL_UCODE_TLV_FLAGS_NEW_NSOFFL_LARGE: new NS offload (large version)
  * @IWL_UCODE_TLV_FLAGS_SCHED_SCAN: this uCode image supports scheduled scan.
  * @IWL_UCODE_TLV_FLAGS_STA_KEY_CMD: new ADD_STA and ADD_STA_KEY command API
+ * @IWL_UCODE_TLV_FLAGS_DEVICE_PS_CMD: support device wide power command
+ *	containing CAM (Continuous Active Mode) indication.
  */
 enum iwl_ucode_tlv_flag {
 	IWL_UCODE_TLV_FLAGS_PAN			= BIT(0),
@@ -107,6 +109,7 @@ enum iwl_ucode_tlv_flag {
 	IWL_UCODE_TLV_FLAGS_NEW_NSOFFL_LARGE	= BIT(16),
 	IWL_UCODE_TLV_FLAGS_SCHED_SCAN		= BIT(17),
 	IWL_UCODE_TLV_FLAGS_STA_KEY_CMD		= BIT(19),
+	IWL_UCODE_TLV_FLAGS_DEVICE_PS_CMD	= BIT(20),
 };
 
 /* The default calibrate table size if not specified by firmware file */

drivers/net/wireless/iwlwifi/mvm/d3.c

@@ -1149,6 +1149,10 @@ static int __iwl_mvm_suspend(struct ieee80211_hw *hw,
 	if (ret)
 		goto out;
 
+	ret = iwl_mvm_power_update_device_mode(mvm);
+	if (ret)
+		goto out;
+
 	ret = iwl_mvm_power_update_mode(mvm, vif);
 	if (ret)
 		goto out;

drivers/net/wireless/iwlwifi/mvm/debugfs.c

@@ -246,60 +246,56 @@ static ssize_t iwl_dbgfs_stations_read(struct file *file, char __user *user_buf,
 	return simple_read_from_buffer(user_buf, count, ppos, buf, pos);
 }
 
-static ssize_t iwl_dbgfs_power_down_allow_write(struct file *file,
-						const char __user *user_buf,
+static ssize_t iwl_dbgfs_disable_power_off_read(struct file *file,
+						char __user *user_buf,
 						size_t count, loff_t *ppos)
 {
 	struct iwl_mvm *mvm = file->private_data;
-	char buf[8] = {};
-	int allow;
-
-	if (!mvm->ucode_loaded)
-		return -EIO;
-
-	count = min_t(size_t, count, sizeof(buf) - 1);
-	if (copy_from_user(buf, user_buf, count))
-		return -EFAULT;
-
-	if (sscanf(buf, "%d", &allow) != 1)
-		return -EINVAL;
+	char buf[64];
+	int bufsz = sizeof(buf);
+	int pos = 0;
 
-	IWL_DEBUG_POWER(mvm, "%s device power down\n",
-			allow ? "allow" : "prevent");
+	pos += scnprintf(buf+pos, bufsz-pos, "disable_power_off_d0=%d\n",
+			 mvm->disable_power_off);
+	pos += scnprintf(buf+pos, bufsz-pos, "disable_power_off_d3=%d\n",
+			 mvm->disable_power_off_d3);
 
-	/*
-	 * TODO: Send REPLY_DEBUG_CMD (0xf0) when FW support it
-	 */
-
-	return count;
+	return simple_read_from_buffer(user_buf, count, ppos, buf, pos);
 }
 
-static ssize_t iwl_dbgfs_power_down_d3_allow_write(struct file *file,
-						   const char __user *user_buf,
-						   size_t count, loff_t *ppos)
+static ssize_t iwl_dbgfs_disable_power_off_write(struct file *file,
+						 const char __user *user_buf,
+						 size_t count, loff_t *ppos)
 {
 	struct iwl_mvm *mvm = file->private_data;
-	char buf[8] = {};
-	int allow;
+	char buf[64] = {};
+	int ret;
+	int val;
+
+	if (!mvm->ucode_loaded)
+		return -EIO;
 
 	count = min_t(size_t, count, sizeof(buf) - 1);
 	if (copy_from_user(buf, user_buf, count))
 		return -EFAULT;
 
-	if (sscanf(buf, "%d", &allow) != 1)
+	if (!strncmp("disable_power_off_d0=", buf, 21)) {
+		if (sscanf(buf + 21, "%d", &val) != 1)
+			return -EINVAL;
+		mvm->disable_power_off = val;
+	} else if (!strncmp("disable_power_off_d3=", buf, 21)) {
+		if (sscanf(buf + 21, "%d", &val) != 1)
+			return -EINVAL;
+		mvm->disable_power_off_d3 = val;
+	} else {
 		return -EINVAL;
+	}
 
-	IWL_DEBUG_POWER(mvm, "%s device power down in d3\n",
-			allow ? "allow" : "prevent");
-
-	/*
-	 * TODO: When WoWLAN FW alive notification happens, driver will send
-	 * REPLY_DEBUG_CMD setting power_down_allow flag according to
-	 * mvm->prevent_power_down_d3
-	 */
-	mvm->prevent_power_down_d3 = !allow;
+	mutex_lock(&mvm->mutex);
+	ret = iwl_mvm_power_update_device_mode(mvm);
+	mutex_unlock(&mvm->mutex);
 
-	return count;
+	return ret ?: count;
 }
 
 static void iwl_dbgfs_update_pm(struct iwl_mvm *mvm,
@@ -397,7 +393,9 @@ static ssize_t iwl_dbgfs_pm_params_write(struct file *file,
 		if (sscanf(buf + 16, "%d", &val) != 1)
 			return -EINVAL;
 		param = MVM_DEBUGFS_PM_TX_DATA_TIMEOUT;
-	} else if (!strncmp("disable_power_off=", buf, 18)) {
+	} else if (!strncmp("disable_power_off=", buf, 18) &&
+		   !(mvm->fw->ucode_capa.flags &
+		     IWL_UCODE_TLV_FLAGS_DEVICE_PS_CMD)) {
 		if (sscanf(buf + 18, "%d", &val) != 1)
 			return -EINVAL;
 		param = MVM_DEBUGFS_PM_DISABLE_POWER_OFF;
@@ -1159,8 +1157,7 @@ MVM_DEBUGFS_READ_WRITE_FILE_OPS(sram);
 MVM_DEBUGFS_READ_FILE_OPS(stations);
 MVM_DEBUGFS_READ_FILE_OPS(bt_notif);
 MVM_DEBUGFS_READ_FILE_OPS(bt_cmd);
-MVM_DEBUGFS_WRITE_FILE_OPS(power_down_allow);
-MVM_DEBUGFS_WRITE_FILE_OPS(power_down_d3_allow);
+MVM_DEBUGFS_READ_WRITE_FILE_OPS(disable_power_off);
 MVM_DEBUGFS_READ_FILE_OPS(fw_rx_stats);
 MVM_DEBUGFS_WRITE_FILE_OPS(fw_restart);
 MVM_DEBUGFS_READ_WRITE_FILE_OPS(scan_ant_rxchain);
@@ -1186,8 +1183,9 @@ int iwl_mvm_dbgfs_register(struct iwl_mvm *mvm, struct dentry *dbgfs_dir)
 	MVM_DEBUGFS_ADD_FILE(stations, dbgfs_dir, S_IRUSR);
 	MVM_DEBUGFS_ADD_FILE(bt_notif, dbgfs_dir, S_IRUSR);
 	MVM_DEBUGFS_ADD_FILE(bt_cmd, dbgfs_dir, S_IRUSR);
-	MVM_DEBUGFS_ADD_FILE(power_down_allow, mvm->debugfs_dir, S_IWUSR);
-	MVM_DEBUGFS_ADD_FILE(power_down_d3_allow, mvm->debugfs_dir, S_IWUSR);
+	if (mvm->fw->ucode_capa.flags & IWL_UCODE_TLV_FLAGS_DEVICE_PS_CMD)
+		MVM_DEBUGFS_ADD_FILE(disable_power_off, mvm->debugfs_dir,
+				     S_IRUSR | S_IWUSR);
 	MVM_DEBUGFS_ADD_FILE(fw_rx_stats, mvm->debugfs_dir, S_IRUSR);
 	MVM_DEBUGFS_ADD_FILE(fw_restart, mvm->debugfs_dir, S_IWUSR);
 	MVM_DEBUGFS_ADD_FILE(scan_ant_rxchain, mvm->debugfs_dir,

drivers/net/wireless/iwlwifi/mvm/fw-api-power.h

@@ -131,6 +131,33 @@ struct iwl_powertable_cmd {
 	__le32 lprx_rssi_threshold;
 } __packed;
 
+/**
+ * enum iwl_device_power_flags - masks for device power command flags
+ * @DEVIC_POWER_FLAGS_POWER_SAVE_ENA_MSK: '1' Allow to save power by turning off
+ *	receiver and transmitter. '0' - does not allow. This flag should be
+ *	always set to '1' unless one need to disable actual power down for debug
+ *	purposes.
+ * @DEVICE_POWER_FLAGS_CAM_MSK: '1' CAM (Continuous Active Mode) is set, meaning
+ *	that power management is disabled. '0' Power management is enabled, one
+ *	of power schemes is applied.
+*/
+enum iwl_device_power_flags {
+	DEVICE_POWER_FLAGS_POWER_SAVE_ENA_MSK	= BIT(0),
+	DEVICE_POWER_FLAGS_CAM_MSK		= BIT(13),
+};
+
+/**
+ * struct iwl_device_power_cmd - device wide power command.
+ * DEVICE_POWER_CMD = 0x77 (command, has simple generic response)
+ *
+ * @flags:	Power table command flags from DEVICE_POWER_FLAGS_*
+ */
+struct iwl_device_power_cmd {
+	/* PM_POWER_TABLE_CMD_API_S_VER_6 */
+	__le16 flags;
+	__le16 reserved;
+} __packed;
+
 /**
  * struct iwl_mac_power_cmd - New power command containing uAPSD support
  * MAC_PM_POWER_TABLE = 0xA9 (command, has simple generic response)

drivers/net/wireless/iwlwifi/mvm/fw.c

@@ -428,6 +428,10 @@ int iwl_mvm_up(struct iwl_mvm *mvm)
 			goto error;
 	}
 
+	ret = iwl_mvm_power_update_device_mode(mvm);
+	if (ret)
+		goto error;
+
 	IWL_DEBUG_INFO(mvm, "RT uCode started.\n");
 	return 0;
  error:

drivers/net/wireless/iwlwifi/mvm/mvm.h

@@ -162,6 +162,7 @@ enum iwl_power_scheme {
 struct iwl_mvm_power_ops {
 	int (*power_update_mode)(struct iwl_mvm *mvm,
 				 struct ieee80211_vif *vif);
+	int (*power_update_device_mode)(struct iwl_mvm *mvm);
 	int (*power_disable)(struct iwl_mvm *mvm, struct ieee80211_vif *vif);
 #ifdef CONFIG_IWLWIFI_DEBUGFS
 	int (*power_dbgfs_read)(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
@@ -489,7 +490,8 @@ struct iwl_mvm {
 #ifdef CONFIG_IWLWIFI_DEBUGFS
 	struct dentry *debugfs_dir;
 	u32 dbgfs_sram_offset, dbgfs_sram_len;
-	bool prevent_power_down_d3;
+	bool disable_power_off;
+	bool disable_power_off_d3;
 #endif
 
 	struct iwl_mvm_phy_ctxt phy_ctxts[NUM_PHY_CTX];
@@ -756,6 +758,13 @@ static inline int iwl_mvm_power_disable(struct iwl_mvm *mvm,
 	return mvm->pm_ops->power_disable(mvm, vif);
 }
 
+static inline int iwl_mvm_power_update_device_mode(struct iwl_mvm *mvm)
+{
+	if (mvm->pm_ops->power_update_device_mode)
+		return mvm->pm_ops->power_update_device_mode(mvm);
+	return 0;
+}
+
 #ifdef CONFIG_IWLWIFI_DEBUGFS
 static inline int iwl_mvm_power_dbgfs_read(struct iwl_mvm *mvm,
 					    struct ieee80211_vif *vif,

drivers/net/wireless/iwlwifi/mvm/power.c

@@ -443,6 +443,32 @@ static int iwl_mvm_power_mac_disable(struct iwl_mvm *mvm,
 				    sizeof(cmd), &cmd);
 }
 
+static int iwl_mvm_power_update_device(struct iwl_mvm *mvm)
+{
+	struct iwl_device_power_cmd cmd = {
+		.flags = cpu_to_le16(DEVICE_POWER_FLAGS_POWER_SAVE_ENA_MSK),
+	};
+
+	if (!(mvm->fw->ucode_capa.flags & IWL_UCODE_TLV_FLAGS_DEVICE_PS_CMD))
+		return 0;
+
+	if (iwlmvm_mod_params.power_scheme == IWL_POWER_SCHEME_CAM)
+		cmd.flags |= cpu_to_le16(DEVICE_POWER_FLAGS_CAM_MSK);
+
+#ifdef CONFIG_IWLWIFI_DEBUGFS
+	if ((mvm->cur_ucode == IWL_UCODE_WOWLAN) ? mvm->disable_power_off_d3 :
+	    mvm->disable_power_off)
+		cmd.flags &=
+			cpu_to_le16(~DEVICE_POWER_FLAGS_POWER_SAVE_ENA_MSK);
+#endif
+	IWL_DEBUG_POWER(mvm,
+			"Sending device power command with flags = 0x%X\n",
+			cmd.flags);
+
+	return iwl_mvm_send_cmd_pdu(mvm, POWER_TABLE_CMD, CMD_SYNC, sizeof(cmd),
+				    &cmd);
+}
+
 #ifdef CONFIG_IWLWIFI_DEBUGFS
 static int iwl_mvm_power_mac_dbgfs_read(struct iwl_mvm *mvm,
 					struct ieee80211_vif *vif, char *buf,
@@ -453,10 +479,11 @@ static int iwl_mvm_power_mac_dbgfs_read(struct iwl_mvm *mvm,
 
 	iwl_mvm_power_build_cmd(mvm, vif, &cmd);
 
-	pos += scnprintf(buf+pos, bufsz-pos, "disable_power_off = %d\n",
-			 (cmd.flags &
-			 cpu_to_le16(POWER_FLAGS_POWER_SAVE_ENA_MSK)) ?
-			 0 : 1);
+	if (!(mvm->fw->ucode_capa.flags & IWL_UCODE_TLV_FLAGS_DEVICE_PS_CMD))
+		pos += scnprintf(buf+pos, bufsz-pos, "disable_power_off = %d\n",
+				 (cmd.flags &
+				 cpu_to_le16(POWER_FLAGS_POWER_SAVE_ENA_MSK)) ?
+				 0 : 1);
 	pos += scnprintf(buf+pos, bufsz-pos, "power_scheme = %d\n",
 			 iwlmvm_mod_params.power_scheme);
 	pos += scnprintf(buf+pos, bufsz-pos, "flags = 0x%x\n",
@@ -622,6 +649,7 @@ int iwl_mvm_update_beacon_filter(struct iwl_mvm *mvm,
 
 const struct iwl_mvm_power_ops pm_mac_ops = {
 	.power_update_mode = iwl_mvm_power_mac_update_mode,
+	.power_update_device_mode = iwl_mvm_power_update_device,
 	.power_disable = iwl_mvm_power_mac_disable,
 #ifdef CONFIG_IWLWIFI_DEBUGFS
 	.power_dbgfs_read = iwl_mvm_power_mac_dbgfs_read,