[openwrt/openwrt] kernel: 5.10: backport QCA83x PHY resume fix, DAC amplitude preferred master, debug reg names

LEDE Commits lede-commits at lists.infradead.org
Sun Oct 24 08:35:27 PDT 2021


hauke pushed a commit to openwrt/openwrt.git, branch master:
https://git.openwrt.org/d888ef5668a9243259381c57439ab5486009b05b

commit d888ef5668a9243259381c57439ab5486009b05b
Author: Matthew Hagan <mnhagan88 at gmail.com>
AuthorDate: Fri Oct 1 21:06:27 2021 +0100

    kernel: 5.10: backport QCA83x PHY resume fix, DAC amplitude preferred master, debug reg names
    
    Backport workaround for QCA8327 PHY resume, which does not properly support
    genphy_suspend/resume. Also add DAC amplitude fix for the QCA8327 PHY,
    set port to preferred master and add proper names to debug regs.
    
    Signed-off-by: Ansuel Smith <ansuelsmth at gmail.com>
    Signed-off-by: Matthew Hagan <mnhagan88 at gmail.com>
---
 ...net-phy-at803x-fix-resume-for-QCA8327-phy.patch | 131 +++++++++++++++++++++
 ...at803x-add-DAC-amplitude-fix-for-8327-phy.patch |  91 ++++++++++++++
 ...03x-enable-prefer-master-for-83xx-interna.patch |  27 +++++
 ...net-phy-at803x-better-describe-debug-regs.patch | 127 ++++++++++++++++++++
 .../730-net-phy-at803x-fix-feature-detection.patch |   4 +-
 5 files changed, 378 insertions(+), 2 deletions(-)

diff --git a/target/linux/generic/backport-5.10/796-v5.16-01-net-phy-at803x-fix-resume-for-QCA8327-phy.patch b/target/linux/generic/backport-5.10/796-v5.16-01-net-phy-at803x-fix-resume-for-QCA8327-phy.patch
new file mode 100644
index 0000000000..5dfe27dd24
--- /dev/null
+++ b/target/linux/generic/backport-5.10/796-v5.16-01-net-phy-at803x-fix-resume-for-QCA8327-phy.patch
@@ -0,0 +1,131 @@
+From ba3c01ee02ed0d821c9f241f179bbc9457542b8f Mon Sep 17 00:00:00 2001
+From: Ansuel Smith <ansuelsmth at gmail.com>
+Date: Sun, 10 Oct 2021 00:46:15 +0200
+Subject: net: phy: at803x: fix resume for QCA8327 phy
+
+From Documentation phy resume triggers phy reset and restart
+auto-negotiation. Add a dedicated function to wait reset to finish as
+it was notice a regression where port sometime are not reliable after a
+suspend/resume session. The reset wait logic is copied from phy_poll_reset.
+Add dedicated suspend function to use genphy_suspend only with QCA8337
+phy and set only additional debug settings for QCA8327. With more test
+it was reported that QCA8327 doesn't proprely support this mode and
+using this cause the unreliability of the switch ports, especially the
+malfunction of the port0.
+
+Fixes: 15b9df4ece17 ("net: phy: at803x: add resume/suspend function to qca83xx phy")
+Signed-off-by: Ansuel Smith <ansuelsmth at gmail.com>
+Signed-off-by: David S. Miller <davem at davemloft.net>
+---
+ drivers/net/phy/at803x.c | 69 +++++++++++++++++++++++++++++++++++++++++++-----
+ 1 file changed, 63 insertions(+), 6 deletions(-)
+
+--- a/drivers/net/phy/at803x.c
++++ b/drivers/net/phy/at803x.c
+@@ -92,9 +92,14 @@
+ #define AT803X_DEBUG_REG_5			0x05
+ #define AT803X_DEBUG_TX_CLK_DLY_EN		BIT(8)
+ 
++#define AT803X_DEBUG_REG_HIB_CTRL		0x0b
++#define   AT803X_DEBUG_HIB_CTRL_SEL_RST_80U	BIT(10)
++#define   AT803X_DEBUG_HIB_CTRL_EN_ANY_CHANGE	BIT(13)
++
+ #define AT803X_DEBUG_REG_3C			0x3C
+ 
+ #define AT803X_DEBUG_REG_3D			0x3D
++#define   AT803X_DEBUG_GATE_CLK_IN1000		BIT(6)
+ 
+ #define AT803X_DEBUG_REG_1F			0x1F
+ #define AT803X_DEBUG_PLL_ON			BIT(2)
+@@ -1220,6 +1225,58 @@ static int qca83xx_config_init(struct ph
+ 	return 0;
+ }
+ 
++static int qca83xx_resume(struct phy_device *phydev)
++{
++	int ret, val;
++
++	/* Skip reset if not suspended */
++	if (!phydev->suspended)
++		return 0;
++
++	/* Reinit the port, reset values set by suspend */
++	qca83xx_config_init(phydev);
++
++	/* Reset the port on port resume */
++	phy_set_bits(phydev, MII_BMCR, BMCR_RESET | BMCR_ANENABLE);
++
++	/* On resume from suspend the switch execute a reset and
++	 * restart auto-negotiation. Wait for reset to complete.
++	 */
++	ret = phy_read_poll_timeout(phydev, MII_BMCR, val, !(val & BMCR_RESET),
++				    50000, 600000, true);
++	if (ret)
++		return ret;
++
++	msleep(1);
++
++	return 0;
++}
++
++static int qca83xx_suspend(struct phy_device *phydev)
++{
++	u16 mask = 0;
++
++	/* Only QCA8337 support actual suspend.
++	 * QCA8327 cause port unreliability when phy suspend
++	 * is set.
++	 */
++	if (phydev->drv->phy_id == QCA8337_PHY_ID) {
++		genphy_suspend(phydev);
++	} else {
++		mask |= ~(BMCR_SPEED1000 | BMCR_FULLDPLX);
++		phy_modify(phydev, MII_BMCR, mask, 0);
++	}
++
++	at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_3D,
++			      AT803X_DEBUG_GATE_CLK_IN1000, 0);
++
++	at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_HIB_CTRL,
++			      AT803X_DEBUG_HIB_CTRL_EN_ANY_CHANGE |
++			      AT803X_DEBUG_HIB_CTRL_SEL_RST_80U, 0);
++
++	return 0;
++}
++
+ static struct phy_driver at803x_driver[] = {
+ {
+ 	/* Qualcomm Atheros AR8035 */
+@@ -1329,8 +1386,8 @@ static struct phy_driver at803x_driver[]
+ 	.get_sset_count		= at803x_get_sset_count,
+ 	.get_strings		= at803x_get_strings,
+ 	.get_stats		= at803x_get_stats,
+-	.suspend		= genphy_suspend,
+-	.resume			= genphy_resume,
++	.suspend		= qca83xx_suspend,
++	.resume			= qca83xx_resume,
+ }, {
+ 	/* QCA8327-A from switch QCA8327-AL1A */
+ 	.phy_id			= QCA8327_A_PHY_ID,
+@@ -1344,8 +1401,8 @@ static struct phy_driver at803x_driver[]
+ 	.get_sset_count		= at803x_get_sset_count,
+ 	.get_strings		= at803x_get_strings,
+ 	.get_stats		= at803x_get_stats,
+-	.suspend		= genphy_suspend,
+-	.resume			= genphy_resume,
++	.suspend		= qca83xx_suspend,
++	.resume			= qca83xx_resume,
+ }, {
+ 	/* QCA8327-B from switch QCA8327-BL1A */
+ 	.phy_id			= QCA8327_B_PHY_ID,
+@@ -1359,8 +1416,8 @@ static struct phy_driver at803x_driver[]
+ 	.get_sset_count		= at803x_get_sset_count,
+ 	.get_strings		= at803x_get_strings,
+ 	.get_stats		= at803x_get_stats,
+-	.suspend		= genphy_suspend,
+-	.resume			= genphy_resume,
++	.suspend		= qca83xx_suspend,
++	.resume			= qca83xx_resume,
+ }, };
+ 
+ module_phy_driver(at803x_driver);
diff --git a/target/linux/generic/backport-5.10/796-v5.16-02-net-phy-at803x-add-DAC-amplitude-fix-for-8327-phy.patch b/target/linux/generic/backport-5.10/796-v5.16-02-net-phy-at803x-add-DAC-amplitude-fix-for-8327-phy.patch
new file mode 100644
index 0000000000..aeb43e2f67
--- /dev/null
+++ b/target/linux/generic/backport-5.10/796-v5.16-02-net-phy-at803x-add-DAC-amplitude-fix-for-8327-phy.patch
@@ -0,0 +1,91 @@
+From 1ca8311949aec5c9447645731ef1c6bc5bd71350 Mon Sep 17 00:00:00 2001
+From: Ansuel Smith <ansuelsmth at gmail.com>
+Date: Sun, 10 Oct 2021 00:46:16 +0200
+Subject: net: phy: at803x: add DAC amplitude fix for 8327 phy
+
+QCA8327 internal phy require DAC amplitude adjustement set to +6% with
+100m speed. Also add additional define to report a change of the same
+reg in QCA8337. (different scope it does set 1000m voltage)
+Add link_change_notify function to set the proper amplitude adjustement
+on PHY_RUNNING state and disable on any other state.
+
+Fixes: b4df02b562f4 ("net: phy: at803x: add support for qca 8327 A variant internal phy")
+Signed-off-by: Ansuel Smith <ansuelsmth at gmail.com>
+Signed-off-by: David S. Miller <davem at davemloft.net>
+---
+ drivers/net/phy/at803x.c | 33 +++++++++++++++++++++++++++++++++
+ 1 file changed, 33 insertions(+)
+
+--- a/drivers/net/phy/at803x.c
++++ b/drivers/net/phy/at803x.c
+@@ -87,6 +87,8 @@
+ #define AT803X_PSSR_MR_AN_COMPLETE	0x0200
+ 
+ #define AT803X_DEBUG_REG_0			0x00
++#define QCA8327_DEBUG_MANU_CTRL_EN		BIT(2)
++#define QCA8337_DEBUG_MANU_CTRL_EN		GENMASK(3, 2)
+ #define AT803X_DEBUG_RX_CLK_DLY_EN		BIT(15)
+ 
+ #define AT803X_DEBUG_REG_5			0x05
+@@ -1222,9 +1224,37 @@ static int qca83xx_config_init(struct ph
+ 		break;
+ 	}
+ 
++	/* QCA8327 require DAC amplitude adjustment for 100m set to +6%.
++	 * Disable on init and enable only with 100m speed following
++	 * qca original source code.
++	 */
++	if (phydev->drv->phy_id == QCA8327_A_PHY_ID ||
++	    phydev->drv->phy_id == QCA8327_B_PHY_ID)
++		at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_0,
++				      QCA8327_DEBUG_MANU_CTRL_EN, 0);
++
+ 	return 0;
+ }
+ 
++static void qca83xx_link_change_notify(struct phy_device *phydev)
++{
++	/* QCA8337 doesn't require DAC Amplitude adjustement */
++	if (phydev->drv->phy_id == QCA8337_PHY_ID)
++		return;
++
++	/* Set DAC Amplitude adjustment to +6% for 100m on link running */
++	if (phydev->state == PHY_RUNNING) {
++		if (phydev->speed == SPEED_100)
++			at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_0,
++					      QCA8327_DEBUG_MANU_CTRL_EN,
++					      QCA8327_DEBUG_MANU_CTRL_EN);
++	} else {
++		/* Reset DAC Amplitude adjustment */
++		at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_0,
++				      QCA8327_DEBUG_MANU_CTRL_EN, 0);
++	}
++}
++
+ static int qca83xx_resume(struct phy_device *phydev)
+ {
+ 	int ret, val;
+@@ -1379,6 +1409,7 @@ static struct phy_driver at803x_driver[]
+ 	.phy_id_mask		= QCA8K_PHY_ID_MASK,
+ 	.name			= "Qualcomm Atheros 8337 internal PHY",
+ 	/* PHY_GBIT_FEATURES */
++	.link_change_notify	= qca83xx_link_change_notify,
+ 	.probe			= at803x_probe,
+ 	.flags			= PHY_IS_INTERNAL,
+ 	.config_init		= qca83xx_config_init,
+@@ -1394,6 +1425,7 @@ static struct phy_driver at803x_driver[]
+ 	.phy_id_mask		= QCA8K_PHY_ID_MASK,
+ 	.name			= "Qualcomm Atheros 8327-A internal PHY",
+ 	/* PHY_GBIT_FEATURES */
++	.link_change_notify	= qca83xx_link_change_notify,
+ 	.probe			= at803x_probe,
+ 	.flags			= PHY_IS_INTERNAL,
+ 	.config_init		= qca83xx_config_init,
+@@ -1409,6 +1441,7 @@ static struct phy_driver at803x_driver[]
+ 	.phy_id_mask		= QCA8K_PHY_ID_MASK,
+ 	.name			= "Qualcomm Atheros 8327-B internal PHY",
+ 	/* PHY_GBIT_FEATURES */
++	.link_change_notify	= qca83xx_link_change_notify,
+ 	.probe			= at803x_probe,
+ 	.flags			= PHY_IS_INTERNAL,
+ 	.config_init		= qca83xx_config_init,
diff --git a/target/linux/generic/backport-5.10/796-v5.16-03-net-phy-at803x-enable-prefer-master-for-83xx-interna.patch b/target/linux/generic/backport-5.10/796-v5.16-03-net-phy-at803x-enable-prefer-master-for-83xx-interna.patch
new file mode 100644
index 0000000000..2352fa0e44
--- /dev/null
+++ b/target/linux/generic/backport-5.10/796-v5.16-03-net-phy-at803x-enable-prefer-master-for-83xx-interna.patch
@@ -0,0 +1,27 @@
+From 9d1c29b4028557a496be9c5eb2b4b86063700636 Mon Sep 17 00:00:00 2001
+From: Ansuel Smith <ansuelsmth at gmail.com>
+Date: Sun, 10 Oct 2021 00:46:17 +0200
+Subject: net: phy: at803x: enable prefer master for 83xx internal phy
+
+From original QCA source code the port was set to prefer master as port
+type in 1000BASE-T mode. Apply the same settings also here.
+
+Signed-off-by: Ansuel Smith <ansuelsmth at gmail.com>
+Reviewed-by: Andrew Lunn <andrew at lunn.ch>
+Signed-off-by: David S. Miller <davem at davemloft.net>
+---
+ drivers/net/phy/at803x.c | 3 +++
+ 1 file changed, 3 insertions(+)
+
+--- a/drivers/net/phy/at803x.c
++++ b/drivers/net/phy/at803x.c
+@@ -1233,6 +1233,9 @@ static int qca83xx_config_init(struct ph
+ 		at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_0,
+ 				      QCA8327_DEBUG_MANU_CTRL_EN, 0);
+ 
++	/* Following original QCA sourcecode set port to prefer master */
++	phy_set_bits(phydev, MII_CTRL1000, CTL1000_PREFER_MASTER);
++
+ 	return 0;
+ }
+ 
diff --git a/target/linux/generic/backport-5.10/796-v5.16-04-net-phy-at803x-better-describe-debug-regs.patch b/target/linux/generic/backport-5.10/796-v5.16-04-net-phy-at803x-better-describe-debug-regs.patch
new file mode 100644
index 0000000000..9c28a893f1
--- /dev/null
+++ b/target/linux/generic/backport-5.10/796-v5.16-04-net-phy-at803x-better-describe-debug-regs.patch
@@ -0,0 +1,127 @@
+From 67999555ff42e91de7654488d9a7735bd9e84555 Mon Sep 17 00:00:00 2001
+From: Ansuel Smith <ansuelsmth at gmail.com>
+Date: Sun, 10 Oct 2021 00:46:18 +0200
+Subject: net: phy: at803x: better describe debug regs
+
+Give a name to known debug regs from Documentation instead of using
+unknown hex values.
+
+Signed-off-by: Ansuel Smith <ansuelsmth at gmail.com>
+Reviewed-by: Andrew Lunn <andrew at lunn.ch>
+Signed-off-by: David S. Miller <davem at davemloft.net>
+---
+ drivers/net/phy/at803x.c | 30 +++++++++++++++---------------
+ 1 file changed, 15 insertions(+), 15 deletions(-)
+
+--- a/drivers/net/phy/at803x.c
++++ b/drivers/net/phy/at803x.c
+@@ -86,12 +86,12 @@
+ #define AT803X_PSSR			0x11	/*PHY-Specific Status Register*/
+ #define AT803X_PSSR_MR_AN_COMPLETE	0x0200
+ 
+-#define AT803X_DEBUG_REG_0			0x00
++#define AT803X_DEBUG_ANALOG_TEST_CTRL		0x00
+ #define QCA8327_DEBUG_MANU_CTRL_EN		BIT(2)
+ #define QCA8337_DEBUG_MANU_CTRL_EN		GENMASK(3, 2)
+ #define AT803X_DEBUG_RX_CLK_DLY_EN		BIT(15)
+ 
+-#define AT803X_DEBUG_REG_5			0x05
++#define AT803X_DEBUG_SYSTEM_CTRL_MODE		0x05
+ #define AT803X_DEBUG_TX_CLK_DLY_EN		BIT(8)
+ 
+ #define AT803X_DEBUG_REG_HIB_CTRL		0x0b
+@@ -100,7 +100,7 @@
+ 
+ #define AT803X_DEBUG_REG_3C			0x3C
+ 
+-#define AT803X_DEBUG_REG_3D			0x3D
++#define AT803X_DEBUG_REG_GREEN			0x3D
+ #define   AT803X_DEBUG_GATE_CLK_IN1000		BIT(6)
+ 
+ #define AT803X_DEBUG_REG_1F			0x1F
+@@ -274,25 +274,25 @@ static int at803x_read_page(struct phy_d
+ 
+ static int at803x_enable_rx_delay(struct phy_device *phydev)
+ {
+-	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_0, 0,
++	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_ANALOG_TEST_CTRL, 0,
+ 				     AT803X_DEBUG_RX_CLK_DLY_EN);
+ }
+ 
+ static int at803x_enable_tx_delay(struct phy_device *phydev)
+ {
+-	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_5, 0,
++	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_SYSTEM_CTRL_MODE, 0,
+ 				     AT803X_DEBUG_TX_CLK_DLY_EN);
+ }
+ 
+ static int at803x_disable_rx_delay(struct phy_device *phydev)
+ {
+-	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_0,
++	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_ANALOG_TEST_CTRL,
+ 				     AT803X_DEBUG_RX_CLK_DLY_EN, 0);
+ }
+ 
+ static int at803x_disable_tx_delay(struct phy_device *phydev)
+ {
+-	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_5,
++	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_SYSTEM_CTRL_MODE,
+ 				     AT803X_DEBUG_TX_CLK_DLY_EN, 0);
+ }
+ 
+@@ -1208,9 +1208,9 @@ static int qca83xx_config_init(struct ph
+ 	switch (switch_revision) {
+ 	case 1:
+ 		/* For 100M waveform */
+-		at803x_debug_reg_write(phydev, AT803X_DEBUG_REG_0, 0x02ea);
++		at803x_debug_reg_write(phydev, AT803X_DEBUG_ANALOG_TEST_CTRL, 0x02ea);
+ 		/* Turn on Gigabit clock */
+-		at803x_debug_reg_write(phydev, AT803X_DEBUG_REG_3D, 0x68a0);
++		at803x_debug_reg_write(phydev, AT803X_DEBUG_REG_GREEN, 0x68a0);
+ 		break;
+ 
+ 	case 2:
+@@ -1218,8 +1218,8 @@ static int qca83xx_config_init(struct ph
+ 		fallthrough;
+ 	case 4:
+ 		phy_write_mmd(phydev, MDIO_MMD_PCS, MDIO_AZ_DEBUG, 0x803f);
+-		at803x_debug_reg_write(phydev, AT803X_DEBUG_REG_3D, 0x6860);
+-		at803x_debug_reg_write(phydev, AT803X_DEBUG_REG_5, 0x2c46);
++		at803x_debug_reg_write(phydev, AT803X_DEBUG_REG_GREEN, 0x6860);
++		at803x_debug_reg_write(phydev, AT803X_DEBUG_SYSTEM_CTRL_MODE, 0x2c46);
+ 		at803x_debug_reg_write(phydev, AT803X_DEBUG_REG_3C, 0x6000);
+ 		break;
+ 	}
+@@ -1230,7 +1230,7 @@ static int qca83xx_config_init(struct ph
+ 	 */
+ 	if (phydev->drv->phy_id == QCA8327_A_PHY_ID ||
+ 	    phydev->drv->phy_id == QCA8327_B_PHY_ID)
+-		at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_0,
++		at803x_debug_reg_mask(phydev, AT803X_DEBUG_ANALOG_TEST_CTRL,
+ 				      QCA8327_DEBUG_MANU_CTRL_EN, 0);
+ 
+ 	/* Following original QCA sourcecode set port to prefer master */
+@@ -1248,12 +1248,12 @@ static void qca83xx_link_change_notify(s
+ 	/* Set DAC Amplitude adjustment to +6% for 100m on link running */
+ 	if (phydev->state == PHY_RUNNING) {
+ 		if (phydev->speed == SPEED_100)
+-			at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_0,
++			at803x_debug_reg_mask(phydev, AT803X_DEBUG_ANALOG_TEST_CTRL,
+ 					      QCA8327_DEBUG_MANU_CTRL_EN,
+ 					      QCA8327_DEBUG_MANU_CTRL_EN);
+ 	} else {
+ 		/* Reset DAC Amplitude adjustment */
+-		at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_0,
++		at803x_debug_reg_mask(phydev, AT803X_DEBUG_ANALOG_TEST_CTRL,
+ 				      QCA8327_DEBUG_MANU_CTRL_EN, 0);
+ 	}
+ }
+@@ -1300,7 +1300,7 @@ static int qca83xx_suspend(struct phy_de
+ 		phy_modify(phydev, MII_BMCR, mask, 0);
+ 	}
+ 
+-	at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_3D,
++	at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_GREEN,
+ 			      AT803X_DEBUG_GATE_CLK_IN1000, 0);
+ 
+ 	at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_HIB_CTRL,
diff --git a/target/linux/generic/pending-5.10/730-net-phy-at803x-fix-feature-detection.patch b/target/linux/generic/pending-5.10/730-net-phy-at803x-fix-feature-detection.patch
index 5caed73372..c49bb19601 100644
--- a/target/linux/generic/pending-5.10/730-net-phy-at803x-fix-feature-detection.patch
+++ b/target/linux/generic/pending-5.10/730-net-phy-at803x-fix-feature-detection.patch
@@ -20,7 +20,7 @@ Signed-off-by: David Bauer <mail at david-bauer.net>
 
 --- a/drivers/net/phy/at803x.c
 +++ b/drivers/net/phy/at803x.c
-@@ -1025,6 +1025,34 @@ static int at803x_set_tunable(struct phy
+@@ -1032,6 +1032,34 @@ static int at803x_set_tunable(struct phy
  	}
  }
  
@@ -55,7 +55,7 @@ Signed-off-by: David Bauer <mail at david-bauer.net>
  static int at803x_cable_test_result_trans(u16 status)
  {
  	switch (FIELD_GET(AT803X_CDT_STATUS_STAT_MASK, status)) {
-@@ -1274,7 +1302,7 @@ static struct phy_driver at803x_driver[]
+@@ -1364,7 +1392,7 @@ static struct phy_driver at803x_driver[]
  	.resume			= at803x_resume,
  	.read_page		= at803x_read_page,
  	.write_page		= at803x_write_page,



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