RTL822x cannot access MDIO_MMD_VEND2 via MII_MMD_CTRL/MII_MMD_DATA.
A mapping to use paged access needs to be used instead.
All other MMD devices can be accessed as usual.
Implement phy_read_mmd and phy_write_mmd using paged access for
MDIO_MMD_VEND2 in Clause-22 mode instead of relying on
MII_MMD_CTRL/MII_MMD_DATA.
This allows eg. rtl822x_config_aneg to work as expected in case the
MDIO bus doesn't support Clause-45 access.
Suggested-by: Bevan Weiss <bevan.weiss@gmail.com>
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
---
drivers/net/phy/realtek/realtek_main.c | 116 ++++++++++++++++++++++++-
1 file changed, 113 insertions(+), 3 deletions(-)
diff --git a/drivers/net/phy/realtek/realtek_main.c b/drivers/net/phy/realtek/realtek_main.c
index 0653a9d8fcb6f..142a5421fe84c 100644
--- a/drivers/net/phy/realtek/realtek_main.c
+++ b/drivers/net/phy/realtek/realtek_main.c
@@ -140,9 +140,8 @@
#define RTL822X_VND1_SERDES_INBAND_ENABLE 0x70d0
#define RTL822X_VND1_SERDES_DATA 0x7589
-/* RTL822X_VND2_XXXXX registers are only accessible when phydev->is_c45
- * is set, they cannot be accessed by C45-over-C22.
- */
+#define RTL822X_VND2_TO_PAGE(reg) ((reg) >> 4)
+#define RTL822X_VND2_TO_PAGE_REG(reg) (16 + (((reg) & GENMASK(3, 0)) >> 1))
#define RTL822X_VND2_C22_REG(reg) (0xa400 + 2 * (reg))
#define RTL8221B_VND2_INER 0xa4d2
@@ -1247,6 +1246,105 @@ static int rtl822x_probe(struct phy_device *phydev)
return 0;
}
+/* RTL822x cannot access MDIO_MMD_VEND2 via MII_MMD_CTRL/MII_MMD_DATA.
+ * A mapping to use paged access needs to be used instead.
+ * All other MMD devices can be accessed as usual.
+ */
+static int rtl822xb_read_mmd(struct phy_device *phydev, int devnum, u16 reg)
+{
+ int oldpage, ret, read_ret;
+ u16 page;
+
+ /* Use Clause-45 bus access in case it is available */
+ if (phydev->is_c45)
+ return __mdiobus_c45_read(phydev->mdio.bus, phydev->mdio.addr,
+ devnum, mmdreg);
+
+ /* Use indirect access via MII_MMD_CTRL and MII_MMD_DATA for all
+ * MMDs except MDIO_MMD_VEND2
+ */
+ if (devnum != MDIO_MMD_VEND2) {
+ __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
+ MII_MMD_CTRL, devnum);
+ __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
+ MII_MMD_DATA, mmdreg);
+ __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
+ MII_MMD_CTRL, devnum | MII_MMD_CTRL_NOINCR);
+
+ return __mdiobus_read(phydev->mdio.bus, phydev->mdio.addr,
+ MII_MMD_DATA);
+ }
+
+ /* Use paged access for MDIO_MMD_VEND2 over Clause-22 */
+ page = RTL822X_VND2_TO_PAGE(reg);
+ oldpage = __phy_read(phydev, RTL821x_PAGE_SELECT);
+ if (oldpage < 0)
+ return ret;
+
+ if (oldpage != page) {
+ ret = __phy_write(phydev, RTL821x_PAGE_SELECT, page);
+ if (ret < 0)
+ return ret;
+ }
+
+ read_ret = __phy_read(phydev, RTL822X_VND2_TO_PAGE_REG(reg));
+ if (oldpage != page) {
+ ret = __phy_write(phydev, RTL821x_PAGE_SELECT, oldpage);
+ if (ret < 0)
+ return ret;
+ }
+
+ return read_ret;
+}
+
+static int rtl822xb_write_mmd(struct phy_device *phydev, int devnum, u16 reg,
+ u16 val)
+{
+ int oldpage, ret, write_ret;
+ u16 page;
+
+ /* Use Clause-45 bus access in case it is available */
+ if (phydev->is_c45)
+ return __mdiobus_c45_write(phydev->mdio.bus, phydev->mdio.addr,
+ devnum, mmdreg, val);
+
+ /* Use indirect access via MII_MMD_CTRL and MII_MMD_DATA for all
+ * MMDs except MDIO_MMD_VEND2
+ */
+ if (devnum != MDIO_MMD_VEND2) {
+ __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
+ MII_MMD_CTRL, devnum);
+ __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
+ MII_MMD_DATA, mmdreg);
+ __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
+ MII_MMD_CTRL, devnum | MII_MMD_CTRL_NOINCR);
+
+ return __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
+ MII_MMD_DATA, val);
+ }
+
+ /* Use paged access for MDIO_MMD_VEND2 over Clause-22 */
+ page = RTL822X_VND2_TO_PAGE(reg);
+ oldpage = __phy_read(phydev, RTL821x_PAGE_SELECT);
+ if (oldpage < 0)
+ return ret;
+
+ if (oldpage != page) {
+ ret = __phy_write(phydev, RTL821x_PAGE_SELECT, page);
+ if (ret < 0)
+ return ret;
+ }
+
+ write_ret = __phy_write(phydev, RTL822X_VND2_TO_PAGE_REG(reg), val);
+ if (oldpage != page) {
+ ret = __phy_write(phydev, RTL821x_PAGE_SELECT, oldpage);
+ if (ret < 0)
+ return ret;
+ }
+
+ return write_ret;
+}
+
static int rtl822x_set_serdes_option_mode(struct phy_device *phydev, bool gen1)
{
bool has_2500, has_sgmii;
@@ -2150,6 +2248,8 @@ static struct phy_driver realtek_drvs[] = {
.resume = rtlgen_resume,
.read_page = rtl821x_read_page,
.write_page = rtl821x_write_page,
+ .read_mmd = rtl822xb_read_mmd,
+ .write_mmd = rtl822xb_write_mmd,
}, {
.match_phy_device = rtl8221b_match_phy_device,
.name = "RTL8226B_RTL8221B 2.5Gbps PHY",
@@ -2164,6 +2264,8 @@ static struct phy_driver realtek_drvs[] = {
.resume = rtlgen_resume,
.read_page = rtl821x_read_page,
.write_page = rtl821x_write_page,
+ .read_mmd = rtl822xb_read_mmd,
+ .write_mmd = rtl822xb_write_mmd,
}, {
PHY_ID_MATCH_EXACT(0x001cc838),
.name = "RTL8226-CG 2.5Gbps PHY",
@@ -2176,6 +2278,8 @@ static struct phy_driver realtek_drvs[] = {
.read_status = rtl822xb_c45_read_status,
.suspend = genphy_c45_pma_suspend,
.resume = rtlgen_c45_resume,
+ .read_mmd = rtl822xb_read_mmd,
+ .write_mmd = rtl822xb_write_mmd,
}, {
PHY_ID_MATCH_EXACT(0x001cc848),
.name = "RTL8226B-CG_RTL8221B-CG 2.5Gbps PHY",
@@ -2190,6 +2294,8 @@ static struct phy_driver realtek_drvs[] = {
.resume = rtlgen_resume,
.read_page = rtl821x_read_page,
.write_page = rtl821x_write_page,
+ .read_mmd = rtl822xb_read_mmd,
+ .write_mmd = rtl822xb_write_mmd,
}, {
.match_phy_device = rtl8221b_vb_cg_c22_match_phy_device,
.name = "RTL8221B-VB-CG 2.5Gbps PHY (C22)",
@@ -2205,6 +2311,8 @@ static struct phy_driver realtek_drvs[] = {
.resume = rtlgen_resume,
.read_page = rtl821x_read_page,
.write_page = rtl821x_write_page,
+ .read_mmd = rtl822xb_read_mmd,
+ .write_mmd = rtl822xb_write_mmd,
}, {
.match_phy_device = rtl8221b_vb_cg_c45_match_phy_device,
.name = "RTL8221B-VB-CG 2.5Gbps PHY (C45)",
@@ -2235,6 +2343,8 @@ static struct phy_driver realtek_drvs[] = {
.resume = rtlgen_resume,
.read_page = rtl821x_read_page,
.write_page = rtl821x_write_page,
+ .read_mmd = rtl822xb_read_mmd,
+ .write_mmd = rtl822xb_write_mmd,
}, {
.match_phy_device = rtl8221b_vm_cg_c45_match_phy_device,
.name = "RTL8221B-VM-CG 2.5Gbps PHY (C45)",
--
2.52.0Hi Daniel,
kernel test robot noticed the following build errors:
[auto build test ERROR on net-next/main]
url: https://github.com/intel-lab-lkp/linux/commits/Daniel-Golle/net-phy-realtek-fix-whitespace-in-struct-phy_driver-initializers/20260104-211500
base: net-next/main
patch link: https://lore.kernel.org/r/d7053fe51fb857b634880be5dcec253858f01aff.1767531485.git.daniel%40makrotopia.org
patch subject: [PATCH net-next 3/4] net: phy: realtek: use paged access for MDIO_MMD_VEND2 in C22 mode
config: x86_64-rhel-9.4-ltp (https://download.01.org/0day-ci/archive/20260105/202601050128.DGivvUie-lkp@intel.com/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260105/202601050128.DGivvUie-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202601050128.DGivvUie-lkp@intel.com/
All errors (new ones prefixed by >>):
drivers/net/phy/realtek/realtek_main.c: In function 'rtl822xb_read_mmd':
>> drivers/net/phy/realtek/realtek_main.c:1261:51: error: 'mmdreg' undeclared (first use in this function); did you mean 'mmdrop'?
1261 | devnum, mmdreg);
| ^~~~~~
| mmdrop
drivers/net/phy/realtek/realtek_main.c:1261:51: note: each undeclared identifier is reported only once for each function it appears in
drivers/net/phy/realtek/realtek_main.c: In function 'rtl822xb_write_mmd':
drivers/net/phy/realtek/realtek_main.c:1309:52: error: 'mmdreg' undeclared (first use in this function); did you mean 'mmdrop'?
1309 | devnum, mmdreg, val);
| ^~~~~~
| mmdrop
vim +1261 drivers/net/phy/realtek/realtek_main.c
1248
1249 /* RTL822x cannot access MDIO_MMD_VEND2 via MII_MMD_CTRL/MII_MMD_DATA.
1250 * A mapping to use paged access needs to be used instead.
1251 * All other MMD devices can be accessed as usual.
1252 */
1253 static int rtl822xb_read_mmd(struct phy_device *phydev, int devnum, u16 reg)
1254 {
1255 int oldpage, ret, read_ret;
1256 u16 page;
1257
1258 /* Use Clause-45 bus access in case it is available */
1259 if (phydev->is_c45)
1260 return __mdiobus_c45_read(phydev->mdio.bus, phydev->mdio.addr,
> 1261 devnum, mmdreg);
1262
1263 /* Use indirect access via MII_MMD_CTRL and MII_MMD_DATA for all
1264 * MMDs except MDIO_MMD_VEND2
1265 */
1266 if (devnum != MDIO_MMD_VEND2) {
1267 __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
1268 MII_MMD_CTRL, devnum);
1269 __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
1270 MII_MMD_DATA, mmdreg);
1271 __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
1272 MII_MMD_CTRL, devnum | MII_MMD_CTRL_NOINCR);
1273
1274 return __mdiobus_read(phydev->mdio.bus, phydev->mdio.addr,
1275 MII_MMD_DATA);
1276 }
1277
1278 /* Use paged access for MDIO_MMD_VEND2 over Clause-22 */
1279 page = RTL822X_VND2_TO_PAGE(reg);
1280 oldpage = __phy_read(phydev, RTL821x_PAGE_SELECT);
1281 if (oldpage < 0)
1282 return ret;
1283
1284 if (oldpage != page) {
1285 ret = __phy_write(phydev, RTL821x_PAGE_SELECT, page);
1286 if (ret < 0)
1287 return ret;
1288 }
1289
1290 read_ret = __phy_read(phydev, RTL822X_VND2_TO_PAGE_REG(reg));
1291 if (oldpage != page) {
1292 ret = __phy_write(phydev, RTL821x_PAGE_SELECT, oldpage);
1293 if (ret < 0)
1294 return ret;
1295 }
1296
1297 return read_ret;
1298 }
1299
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Hi Daniel,
kernel test robot noticed the following build errors:
[auto build test ERROR on net-next/main]
url: https://github.com/intel-lab-lkp/linux/commits/Daniel-Golle/net-phy-realtek-fix-whitespace-in-struct-phy_driver-initializers/20260104-211500
base: net-next/main
patch link: https://lore.kernel.org/r/d7053fe51fb857b634880be5dcec253858f01aff.1767531485.git.daniel%40makrotopia.org
patch subject: [PATCH net-next 3/4] net: phy: realtek: use paged access for MDIO_MMD_VEND2 in C22 mode
config: x86_64-kexec (https://download.01.org/0day-ci/archive/20260104/202601042339.7aMa6atC-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260104/202601042339.7aMa6atC-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202601042339.7aMa6atC-lkp@intel.com/
All errors (new ones prefixed by >>):
>> drivers/net/phy/realtek/realtek_main.c:1261:16: error: use of undeclared identifier 'mmdreg'; did you mean 'mmdrop'?
1261 | devnum, mmdreg);
| ^~~~~~
| mmdrop
include/linux/sched/mm.h:47:20: note: 'mmdrop' declared here
47 | static inline void mmdrop(struct mm_struct *mm)
| ^
drivers/net/phy/realtek/realtek_main.c:1270:19: error: use of undeclared identifier 'mmdreg'; did you mean 'mmdrop'?
1270 | MII_MMD_DATA, mmdreg);
| ^~~~~~
| mmdrop
include/linux/sched/mm.h:47:20: note: 'mmdrop' declared here
47 | static inline void mmdrop(struct mm_struct *mm)
| ^
drivers/net/phy/realtek/realtek_main.c:1309:17: error: use of undeclared identifier 'mmdreg'; did you mean 'mmdrop'?
1309 | devnum, mmdreg, val);
| ^~~~~~
| mmdrop
include/linux/sched/mm.h:47:20: note: 'mmdrop' declared here
47 | static inline void mmdrop(struct mm_struct *mm)
| ^
drivers/net/phy/realtek/realtek_main.c:1318:19: error: use of undeclared identifier 'mmdreg'; did you mean 'mmdrop'?
1318 | MII_MMD_DATA, mmdreg);
| ^~~~~~
| mmdrop
include/linux/sched/mm.h:47:20: note: 'mmdrop' declared here
47 | static inline void mmdrop(struct mm_struct *mm)
| ^
4 errors generated.
vim +1261 drivers/net/phy/realtek/realtek_main.c
1248
1249 /* RTL822x cannot access MDIO_MMD_VEND2 via MII_MMD_CTRL/MII_MMD_DATA.
1250 * A mapping to use paged access needs to be used instead.
1251 * All other MMD devices can be accessed as usual.
1252 */
1253 static int rtl822xb_read_mmd(struct phy_device *phydev, int devnum, u16 reg)
1254 {
1255 int oldpage, ret, read_ret;
1256 u16 page;
1257
1258 /* Use Clause-45 bus access in case it is available */
1259 if (phydev->is_c45)
1260 return __mdiobus_c45_read(phydev->mdio.bus, phydev->mdio.addr,
> 1261 devnum, mmdreg);
1262
1263 /* Use indirect access via MII_MMD_CTRL and MII_MMD_DATA for all
1264 * MMDs except MDIO_MMD_VEND2
1265 */
1266 if (devnum != MDIO_MMD_VEND2) {
1267 __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
1268 MII_MMD_CTRL, devnum);
1269 __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
1270 MII_MMD_DATA, mmdreg);
1271 __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
1272 MII_MMD_CTRL, devnum | MII_MMD_CTRL_NOINCR);
1273
1274 return __mdiobus_read(phydev->mdio.bus, phydev->mdio.addr,
1275 MII_MMD_DATA);
1276 }
1277
1278 /* Use paged access for MDIO_MMD_VEND2 over Clause-22 */
1279 page = RTL822X_VND2_TO_PAGE(reg);
1280 oldpage = __phy_read(phydev, RTL821x_PAGE_SELECT);
1281 if (oldpage < 0)
1282 return ret;
1283
1284 if (oldpage != page) {
1285 ret = __phy_write(phydev, RTL821x_PAGE_SELECT, page);
1286 if (ret < 0)
1287 return ret;
1288 }
1289
1290 read_ret = __phy_read(phydev, RTL822X_VND2_TO_PAGE_REG(reg));
1291 if (oldpage != page) {
1292 ret = __phy_write(phydev, RTL821x_PAGE_SELECT, oldpage);
1293 if (ret < 0)
1294 return ret;
1295 }
1296
1297 return read_ret;
1298 }
1299
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
On Sun, Jan 04, 2026 at 01:12:13PM +0000, Daniel Golle wrote:
> +static int rtl822xb_read_mmd(struct phy_device *phydev, int devnum, u16 reg)
> +{
> + int oldpage, ret, read_ret;
> + u16 page;
> +
> + /* Use Clause-45 bus access in case it is available */
> + if (phydev->is_c45)
> + return __mdiobus_c45_read(phydev->mdio.bus, phydev->mdio.addr,
> + devnum, mmdreg);
> +
> + /* Use indirect access via MII_MMD_CTRL and MII_MMD_DATA for all
> + * MMDs except MDIO_MMD_VEND2
> + */
> + if (devnum != MDIO_MMD_VEND2) {
> + __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
> + MII_MMD_CTRL, devnum);
> + __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
> + MII_MMD_DATA, mmdreg);
> + __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
> + MII_MMD_CTRL, devnum | MII_MMD_CTRL_NOINCR);
> +
> + return __mdiobus_read(phydev->mdio.bus, phydev->mdio.addr,
> + MII_MMD_DATA);
> + }
I think I'd prefer this structure:
if (devnum != MDIO_MMD_VEND2)
return mmd_phy_read(phydev->mdio.bus, phydev->mdio.addr,
phydev->is_c45, devnum, regad);
if (phydev->is_c45)
return __mdiobus_c45_read(phydev->mdio.bus, phydev->mdio.addr,
devnum, mmdreg);
rather than open-coding the indirect access, or the reverse order with
mmd_phy_read() called with is_c45 set to false.
Same for the write function.
Thanks.
--
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!
On Sun, Jan 04, 2026 at 09:23:00PM +0000, Russell King (Oracle) wrote:
> On Sun, Jan 04, 2026 at 01:12:13PM +0000, Daniel Golle wrote:
> > +static int rtl822xb_read_mmd(struct phy_device *phydev, int devnum, u16 reg)
> > +{
> > + int oldpage, ret, read_ret;
> > + u16 page;
> > +
> > + /* Use Clause-45 bus access in case it is available */
> > + if (phydev->is_c45)
> > + return __mdiobus_c45_read(phydev->mdio.bus, phydev->mdio.addr,
> > + devnum, mmdreg);
> > +
> > + /* Use indirect access via MII_MMD_CTRL and MII_MMD_DATA for all
> > + * MMDs except MDIO_MMD_VEND2
> > + */
> > + if (devnum != MDIO_MMD_VEND2) {
> > + __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
> > + MII_MMD_CTRL, devnum);
> > + __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
> > + MII_MMD_DATA, mmdreg);
> > + __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
> > + MII_MMD_CTRL, devnum | MII_MMD_CTRL_NOINCR);
> > +
> > + return __mdiobus_read(phydev->mdio.bus, phydev->mdio.addr,
> > + MII_MMD_DATA);
> > + }
>
> I think I'd prefer this structure:
>
> if (devnum != MDIO_MMD_VEND2)
> return mmd_phy_read(phydev->mdio.bus, phydev->mdio.addr,
> phydev->is_c45, devnum, regad);
>
> if (phydev->is_c45)
> return __mdiobus_c45_read(phydev->mdio.bus, phydev->mdio.addr,
> devnum, mmdreg);
Even this would be possible then:
if (devnum != MDIO_MMD_VEND2 || phydev->is_c45)
return mmd_phy_read(phydev->mdio.bus, phydev->mdio.addr,
phydev->is_c45, devnum, regad);
>
> rather than open-coding the indirect access, or the reverse order with
> mmd_phy_read() called with is_c45 set to false.
>
> Same for the write function.
I also thought it'd be good to do that, but that would require moving
the function prototypes from drivers/net/phy/phylib-internal.h to a
public header which the PHY driver may include, eg. phylib.h. (I suppose
that 'phylib-internal.h' should not be included in PHY drivers).
Needless to say that I also don't fancy open-coding unlocked variants
of phy_{read,write}_paged, but that's on a other story...
On 1/4/2026 6:42 PM, Daniel Golle wrote:
> +static int rtl822xb_read_mmd(struct phy_device *phydev, int devnum, u16 reg)
> +{
> + int oldpage, ret, read_ret;
> + u16 page;
> +
> + /* Use Clause-45 bus access in case it is available */
> + if (phydev->is_c45)
> + return __mdiobus_c45_read(phydev->mdio.bus, phydev->mdio.addr,
> + devnum, mmdreg);
> +
mmdreg is not defined.
> + /* Use indirect access via MII_MMD_CTRL and MII_MMD_DATA for all
> + * MMDs except MDIO_MMD_VEND2
> + */
> + if (devnum != MDIO_MMD_VEND2) {
> + __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
> + MII_MMD_CTRL, devnum);
> + __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
> + MII_MMD_DATA, mmdreg);
> + __mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
> + MII_MMD_CTRL, devnum | MII_MMD_CTRL_NOINCR);
> +
> + return __mdiobus_read(phydev->mdio.bus, phydev->mdio.addr,
> + MII_MMD_DATA);
> + }
> +
> + /* Use paged access for MDIO_MMD_VEND2 over Clause-22 */
> + page = RTL822X_VND2_TO_PAGE(reg);
> + oldpage = __phy_read(phydev, RTL821x_PAGE_SELECT);
> + if (oldpage < 0)
> + return ret;
> +
> + if (oldpage != page) {
> + ret = __phy_write(phydev, RTL821x_PAGE_SELECT, page);
> + if (ret < 0)
> + return ret;
> + }
> +
> + read_ret = __phy_read(phydev, RTL822X_VND2_TO_PAGE_REG(reg));
> + if (oldpage != page) {
> + ret = __phy_write(phydev, RTL821x_PAGE_SELECT, oldpage);
> + if (ret < 0)
> + return ret;
> + }
> +
> + return read_ret;
> +}
Thanks,
Alok
© 2016 - 2026 Red Hat, Inc.