ath9k: Add a debugfs file to adjust antenna diversity

Location: /<debugfs>/ieee80211/phy#/ath9k/diversity
Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath9k/ar9003_phy.c

@@ -1360,7 +1360,7 @@ static void ar9003_hw_antctrl_shared_chain_lnadiv(struct ath_hw *ah,
 	if (enable) {
 		REG_SET_BIT(ah, AR_PHY_MC_GAIN_CTRL,
 			    (1 << AR_PHY_ANT_SW_RX_PROT_S));
-		if (IS_CHAN_2GHZ(ah->curchan))
+		if (ah->curchan && IS_CHAN_2GHZ(ah->curchan))
 			REG_SET_BIT(ah, AR_PHY_RESTART,
 				    AR_PHY_RESTART_ENABLE_DIV_M2FLAG);
 		REG_SET_BIT(ah, AR_BTCOEX_WL_LNADIV,

drivers/net/wireless/ath/ath9k/debug.c

@@ -222,6 +222,57 @@ static const struct file_operations fops_disable_ani = {
 	.llseek = default_llseek,
 };
 
+static ssize_t read_file_ant_diversity(struct file *file, char __user *user_buf,
+				       size_t count, loff_t *ppos)
+{
+	struct ath_softc *sc = file->private_data;
+	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
+	char buf[32];
+	unsigned int len;
+
+	len = sprintf(buf, "%d\n", common->antenna_diversity);
+	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
+}
+
+static ssize_t write_file_ant_diversity(struct file *file,
+					const char __user *user_buf,
+					size_t count, loff_t *ppos)
+{
+	struct ath_softc *sc = file->private_data;
+	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
+	unsigned long antenna_diversity;
+	char buf[32];
+	ssize_t len;
+
+	len = min(count, sizeof(buf) - 1);
+	if (copy_from_user(buf, user_buf, len))
+		return -EFAULT;
+
+	if (!AR_SREV_9565(sc->sc_ah))
+		goto exit;
+
+	buf[len] = '\0';
+	if (strict_strtoul(buf, 0, &antenna_diversity))
+		return -EINVAL;
+
+	common->antenna_diversity = !!antenna_diversity;
+	ath9k_ps_wakeup(sc);
+	ath_ant_comb_update(sc);
+	ath_dbg(common, CONFIG, "Antenna diversity: %d\n",
+		common->antenna_diversity);
+	ath9k_ps_restore(sc);
+exit:
+	return count;
+}
+
+static const struct file_operations fops_ant_diversity = {
+	.read = read_file_ant_diversity,
+	.write = write_file_ant_diversity,
+	.open = simple_open,
+	.owner = THIS_MODULE,
+	.llseek = default_llseek,
+};
+
 static ssize_t read_file_dma(struct file *file, char __user *user_buf,
 			     size_t count, loff_t *ppos)
 {
@@ -1599,12 +1650,12 @@ int ath9k_init_debug(struct ath_hw *ah)
 	debugfs_create_file("samples", S_IRUSR, sc->debug.debugfs_phy, sc,
 			    &fops_samps);
 #endif
-
 	debugfs_create_u32("gpio_mask", S_IRUSR | S_IWUSR,
 			   sc->debug.debugfs_phy, &sc->sc_ah->gpio_mask);
-
 	debugfs_create_u32("gpio_val", S_IRUSR | S_IWUSR,
 			   sc->debug.debugfs_phy, &sc->sc_ah->gpio_val);
+	debugfs_create_file("diversity", S_IRUSR | S_IWUSR,
+			    sc->debug.debugfs_phy, sc, &fops_ant_diversity);
 
 	return 0;
 }