net: dsa: mv88e6xxx: Add support for model-specific pre- and post-reset handlers

Instead of calling mv88e6xxx_g2_eeprom_wait() directly from
mv88e6xxx_hardware_reset(), add configurable pre- and post-reset hard
reset handlers. Initially, the handlers are set to
mv88e6xxx_g2_eeprom_wait() for all families that have get/set_eeprom()
to match the existing behavior. No functional change intended (except
for additional error messages on failure).

Fixes: 6ccf50d4d474 ("net: dsa: mv88e6xxx: Avoid EEPROM timeout when EEPROM is absent")
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 52 insertions, 4 deletions

diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index e950a634a3c73..4bdb3f2d469e3 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -3086,6 +3086,7 @@ static int mv88e6xxx_software_reset(struct mv88e6xxx_chip *chip)
 static void mv88e6xxx_hardware_reset(struct mv88e6xxx_chip *chip)
 {
 	struct gpio_desc *gpiod = chip->reset;
+	int err;
 
 	/* If there is a GPIO connected to the reset pin, toggle it */
 	if (gpiod) {
@@ -3094,17 +3095,26 @@ static void mv88e6xxx_hardware_reset(struct mv88e6xxx_chip *chip)
 		 * mid-byte, causing the first EEPROM read after the reset
 		 * from the wrong location resulting in the switch booting
 		 * to wrong mode and inoperable.
+		 * For this reason, switch families with EEPROM support
+		 * generally wait for EEPROM loads to complete as their pre-
+		 * and post-reset handlers.
 		 */
-		if (chip->info->ops->get_eeprom)
-			mv88e6xxx_g2_eeprom_wait(chip);
+		if (chip->info->ops->hardware_reset_pre) {
+			err = chip->info->ops->hardware_reset_pre(chip);
+			if (err)
+				dev_err(chip->dev, "pre-reset error: %d\n", err);
+		}
 
 		gpiod_set_value_cansleep(gpiod, 1);
 		usleep_range(10000, 20000);
 		gpiod_set_value_cansleep(gpiod, 0);
 		usleep_range(10000, 20000);
 
-		if (chip->info->ops->get_eeprom)
-			mv88e6xxx_g2_eeprom_wait(chip);
+		if (chip->info->ops->hardware_reset_post) {
+			err = chip->info->ops->hardware_reset_post(chip);
+			if (err)
+				dev_err(chip->dev, "post-reset error: %d\n", err);
+		}
 	}
 }
 
@@ -4334,6 +4344,8 @@ static const struct mv88e6xxx_ops mv88e6141_ops = {
 	.watchdog_ops = &mv88e6390_watchdog_ops,
 	.mgmt_rsvd2cpu =  mv88e6390_g1_mgmt_rsvd2cpu,
 	.pot_clear = mv88e6xxx_g2_pot_clear,
+	.hardware_reset_pre = mv88e6xxx_g2_eeprom_wait,
+	.hardware_reset_post = mv88e6xxx_g2_eeprom_wait,
 	.reset = mv88e6352_g1_reset,
 	.rmu_disable = mv88e6390_g1_rmu_disable,
 	.atu_get_hash = mv88e6165_g1_atu_get_hash,
@@ -4524,6 +4536,8 @@ static const struct mv88e6xxx_ops mv88e6172_ops = {
 	.watchdog_ops = &mv88e6097_watchdog_ops,
 	.mgmt_rsvd2cpu = mv88e6352_g2_mgmt_rsvd2cpu,
 	.pot_clear = mv88e6xxx_g2_pot_clear,
+	.hardware_reset_pre = mv88e6xxx_g2_eeprom_wait,
+	.hardware_reset_post = mv88e6xxx_g2_eeprom_wait,
 	.reset = mv88e6352_g1_reset,
 	.rmu_disable = mv88e6352_g1_rmu_disable,
 	.atu_get_hash = mv88e6165_g1_atu_get_hash,
@@ -4624,6 +4638,8 @@ static const struct mv88e6xxx_ops mv88e6176_ops = {
 	.watchdog_ops = &mv88e6097_watchdog_ops,
 	.mgmt_rsvd2cpu = mv88e6352_g2_mgmt_rsvd2cpu,
 	.pot_clear = mv88e6xxx_g2_pot_clear,
+	.hardware_reset_pre = mv88e6xxx_g2_eeprom_wait,
+	.hardware_reset_post = mv88e6xxx_g2_eeprom_wait,
 	.reset = mv88e6352_g1_reset,
 	.rmu_disable = mv88e6352_g1_rmu_disable,
 	.atu_get_hash = mv88e6165_g1_atu_get_hash,
@@ -4718,6 +4734,8 @@ static const struct mv88e6xxx_ops mv88e6190_ops = {
 	.watchdog_ops = &mv88e6390_watchdog_ops,
 	.mgmt_rsvd2cpu = mv88e6390_g1_mgmt_rsvd2cpu,
 	.pot_clear = mv88e6xxx_g2_pot_clear,
+	.hardware_reset_pre = mv88e6xxx_g2_eeprom_wait,
+	.hardware_reset_post = mv88e6xxx_g2_eeprom_wait,
 	.reset = mv88e6352_g1_reset,
 	.rmu_disable = mv88e6390_g1_rmu_disable,
 	.atu_get_hash = mv88e6165_g1_atu_get_hash,
@@ -4776,6 +4794,8 @@ static const struct mv88e6xxx_ops mv88e6190x_ops = {
 	.watchdog_ops = &mv88e6390_watchdog_ops,
 	.mgmt_rsvd2cpu = mv88e6390_g1_mgmt_rsvd2cpu,
 	.pot_clear = mv88e6xxx_g2_pot_clear,
+	.hardware_reset_pre = mv88e6xxx_g2_eeprom_wait,
+	.hardware_reset_post = mv88e6xxx_g2_eeprom_wait,
 	.reset = mv88e6352_g1_reset,
 	.rmu_disable = mv88e6390_g1_rmu_disable,
 	.atu_get_hash = mv88e6165_g1_atu_get_hash,
@@ -4832,6 +4852,8 @@ static const struct mv88e6xxx_ops mv88e6191_ops = {
 	.watchdog_ops = &mv88e6390_watchdog_ops,
 	.mgmt_rsvd2cpu = mv88e6390_g1_mgmt_rsvd2cpu,
 	.pot_clear = mv88e6xxx_g2_pot_clear,
+	.hardware_reset_pre = mv88e6xxx_g2_eeprom_wait,
+	.hardware_reset_post = mv88e6xxx_g2_eeprom_wait,
 	.reset = mv88e6352_g1_reset,
 	.rmu_disable = mv88e6390_g1_rmu_disable,
 	.atu_get_hash = mv88e6165_g1_atu_get_hash,
@@ -4891,6 +4913,8 @@ static const struct mv88e6xxx_ops mv88e6240_ops = {
 	.watchdog_ops = &mv88e6097_watchdog_ops,
 	.mgmt_rsvd2cpu = mv88e6352_g2_mgmt_rsvd2cpu,
 	.pot_clear = mv88e6xxx_g2_pot_clear,
+	.hardware_reset_pre = mv88e6xxx_g2_eeprom_wait,
+	.hardware_reset_post = mv88e6xxx_g2_eeprom_wait,
 	.reset = mv88e6352_g1_reset,
 	.rmu_disable = mv88e6352_g1_rmu_disable,
 	.atu_get_hash = mv88e6165_g1_atu_get_hash,
@@ -4944,6 +4968,8 @@ static const struct mv88e6xxx_ops mv88e6250_ops = {
 	.watchdog_ops = &mv88e6250_watchdog_ops,
 	.mgmt_rsvd2cpu = mv88e6352_g2_mgmt_rsvd2cpu,
 	.pot_clear = mv88e6xxx_g2_pot_clear,
+	.hardware_reset_pre = mv88e6xxx_g2_eeprom_wait,
+	.hardware_reset_post = mv88e6xxx_g2_eeprom_wait,
 	.reset = mv88e6250_g1_reset,
 	.vtu_getnext = mv88e6185_g1_vtu_getnext,
 	.vtu_loadpurge = mv88e6185_g1_vtu_loadpurge,
@@ -4991,6 +5017,8 @@ static const struct mv88e6xxx_ops mv88e6290_ops = {
 	.watchdog_ops = &mv88e6390_watchdog_ops,
 	.mgmt_rsvd2cpu = mv88e6390_g1_mgmt_rsvd2cpu,
 	.pot_clear = mv88e6xxx_g2_pot_clear,
+	.hardware_reset_pre = mv88e6xxx_g2_eeprom_wait,
+	.hardware_reset_post = mv88e6xxx_g2_eeprom_wait,
 	.reset = mv88e6352_g1_reset,
 	.rmu_disable = mv88e6390_g1_rmu_disable,
 	.atu_get_hash = mv88e6165_g1_atu_get_hash,
@@ -5050,6 +5078,8 @@ static const struct mv88e6xxx_ops mv88e6320_ops = {
 	.watchdog_ops = &mv88e6390_watchdog_ops,
 	.mgmt_rsvd2cpu = mv88e6352_g2_mgmt_rsvd2cpu,
 	.pot_clear = mv88e6xxx_g2_pot_clear,
+	.hardware_reset_pre = mv88e6xxx_g2_eeprom_wait,
+	.hardware_reset_post = mv88e6xxx_g2_eeprom_wait,
 	.reset = mv88e6352_g1_reset,
 	.vtu_getnext = mv88e6185_g1_vtu_getnext,
 	.vtu_loadpurge = mv88e6185_g1_vtu_loadpurge,
@@ -5096,6 +5126,8 @@ static const struct mv88e6xxx_ops mv88e6321_ops = {
 	.set_egress_port = mv88e6095_g1_set_egress_port,
 	.watchdog_ops = &mv88e6390_watchdog_ops,
 	.mgmt_rsvd2cpu = mv88e6352_g2_mgmt_rsvd2cpu,
+	.hardware_reset_pre = mv88e6xxx_g2_eeprom_wait,
+	.hardware_reset_post = mv88e6xxx_g2_eeprom_wait,
 	.reset = mv88e6352_g1_reset,
 	.vtu_getnext = mv88e6185_g1_vtu_getnext,
 	.vtu_loadpurge = mv88e6185_g1_vtu_loadpurge,
@@ -5146,6 +5178,8 @@ static const struct mv88e6xxx_ops mv88e6341_ops = {
 	.watchdog_ops = &mv88e6390_watchdog_ops,
 	.mgmt_rsvd2cpu =  mv88e6390_g1_mgmt_rsvd2cpu,
 	.pot_clear = mv88e6xxx_g2_pot_clear,
+	.hardware_reset_pre = mv88e6xxx_g2_eeprom_wait,
+	.hardware_reset_post = mv88e6xxx_g2_eeprom_wait,
 	.reset = mv88e6352_g1_reset,
 	.rmu_disable = mv88e6390_g1_rmu_disable,
 	.atu_get_hash = mv88e6165_g1_atu_get_hash,
@@ -5301,6 +5335,8 @@ static const struct mv88e6xxx_ops mv88e6352_ops = {
 	.watchdog_ops = &mv88e6097_watchdog_ops,
 	.mgmt_rsvd2cpu = mv88e6352_g2_mgmt_rsvd2cpu,
 	.pot_clear = mv88e6xxx_g2_pot_clear,
+	.hardware_reset_pre = mv88e6xxx_g2_eeprom_wait,
+	.hardware_reset_post = mv88e6xxx_g2_eeprom_wait,
 	.reset = mv88e6352_g1_reset,
 	.rmu_disable = mv88e6352_g1_rmu_disable,
 	.atu_get_hash = mv88e6165_g1_atu_get_hash,
@@ -5363,6 +5399,8 @@ static const struct mv88e6xxx_ops mv88e6390_ops = {
 	.watchdog_ops = &mv88e6390_watchdog_ops,
 	.mgmt_rsvd2cpu = mv88e6390_g1_mgmt_rsvd2cpu,
 	.pot_clear = mv88e6xxx_g2_pot_clear,
+	.hardware_reset_pre = mv88e6xxx_g2_eeprom_wait,
+	.hardware_reset_post = mv88e6xxx_g2_eeprom_wait,
 	.reset = mv88e6352_g1_reset,
 	.rmu_disable = mv88e6390_g1_rmu_disable,
 	.atu_get_hash = mv88e6165_g1_atu_get_hash,
@@ -5425,6 +5463,8 @@ static const struct mv88e6xxx_ops mv88e6390x_ops = {
 	.watchdog_ops = &mv88e6390_watchdog_ops,
 	.mgmt_rsvd2cpu = mv88e6390_g1_mgmt_rsvd2cpu,
 	.pot_clear = mv88e6xxx_g2_pot_clear,
+	.hardware_reset_pre = mv88e6xxx_g2_eeprom_wait,
+	.hardware_reset_post = mv88e6xxx_g2_eeprom_wait,
 	.reset = mv88e6352_g1_reset,
 	.rmu_disable = mv88e6390_g1_rmu_disable,
 	.atu_get_hash = mv88e6165_g1_atu_get_hash,
@@ -5490,6 +5530,8 @@ static const struct mv88e6xxx_ops mv88e6393x_ops = {
 	.watchdog_ops = &mv88e6393x_watchdog_ops,
 	.mgmt_rsvd2cpu = mv88e6393x_port_mgmt_rsvd2cpu,
 	.pot_clear = mv88e6xxx_g2_pot_clear,
+	.hardware_reset_pre = mv88e6xxx_g2_eeprom_wait,
+	.hardware_reset_post = mv88e6xxx_g2_eeprom_wait,
 	.reset = mv88e6352_g1_reset,
 	.rmu_disable = mv88e6390_g1_rmu_disable,
 	.atu_get_hash = mv88e6165_g1_atu_get_hash,
diff --git a/drivers/net/dsa/mv88e6xxx/chip.h b/drivers/net/dsa/mv88e6xxx/chip.h
index 85eb293381a7e..c34caf9815c5c 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.h
+++ b/drivers/net/dsa/mv88e6xxx/chip.h
@@ -487,6 +487,12 @@ struct mv88e6xxx_ops {
 	int (*ppu_enable)(struct mv88e6xxx_chip *chip);
 	int (*ppu_disable)(struct mv88e6xxx_chip *chip);
 
+	/* Additional handlers to run before and after hard reset, to make sure
+	 * that the switch and EEPROM are in a good state.
+	 */
+	int (*hardware_reset_pre)(struct mv88e6xxx_chip *chip);
+	int (*hardware_reset_post)(struct mv88e6xxx_chip *chip);
+
 	/* Switch Software Reset */
 	int (*reset)(struct mv88e6xxx_chip *chip);