[PATCH 5.15 049/128] r8152: fix the force speed doesnt work for RTL8156

Greg Kroah-Hartman
2021-12-27T15:49:28Z

From: Hayes Wang <hayeswang@realtek.com>

[ Upstream commit 45bf944e6703d43fe5e285808312acd8a34c1a24 ]

It needs to set mdio force mode. Otherwise, link off always occurs when
setting force speed.

Fixes: 195aae321c82 ("r8152: support new chips")
Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/usb/r8152.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)

diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c
index d3da350777a4d..3364e54c177ff 100644
--- a/drivers/net/usb/r8152.c
+++ b/drivers/net/usb/r8152.c
@@ -6584,6 +6584,21 @@ static bool rtl8153_in_nway(struct r8152 *tp)
return true;
}

+static void r8156_mdio_force_mode(struct r8152 *tp)
+{
+ u16 data;
+
+ /* Select force mode through 0xa5b4 bit 15
+ * 0: MDIO force mode
+ * 1: MMD force mode
+ */
+ data = ocp_reg_read(tp, 0xa5b4);
+ if (data & BIT(15)) {
+ data &= ~BIT(15);
+ ocp_reg_write(tp, 0xa5b4, data);
+ }
+}
+
static void set_carrier(struct r8152 *tp)
{
struct net_device *netdev = tp->netdev;
@@ -8016,6 +8031,7 @@ static void r8156_init(struct r8152 *tp)
ocp_data |= ACT_ODMA;
ocp_write_byte(tp, MCU_TYPE_USB, USB_BMU_CONFIG, ocp_data);

+ r8156_mdio_force_mode(tp);
rtl_tally_reset(tp);

tp->coalesce = 15000; /* 15 us */
@@ -8145,6 +8161,7 @@ static void r8156b_init(struct r8152 *tp)
ocp_data &= ~(RX_AGG_DISABLE | RX_ZERO_EN);
ocp_write_word(tp, MCU_TYPE_USB, USB_USB_CTRL, ocp_data);

+ r8156_mdio_force_mode(tp);
rtl_tally_reset(tp);

tp->coalesce = 15000; /* 15 us */
--
2.34.1