[PATCH net-next v5 5/9] net: dsa: mt7530: replace mt7530_read with regmap_read

From: Daniel Golle

Date: Mon Aug 31 2026 - 14:46:26 EST

Replace all mt7530_read() calls with direct regmap_read() calls and
remove the wrapper function. The wrapper returned 0 on failed reads;
preserve that behaviour by zeroing the read-back buffer at the start of
mt7530_regmap_read(), so callers that do not check the return code keep
seeing a deterministic value. The WARN_ON_ONCE error logging is dropped.

Most callsites follow the val = mt7530_read(priv, reg) pattern and are
converted mechanically using the following semantic patch:

@@
expression priv, reg;
identifier val;
@@
-val = mt7530_read(priv, reg);
+regmap_read(priv->regmap, reg, &val);

Remaining inline uses are converted by hand.

Signed-off-by: Daniel Golle <daniel@xxxxxxxxxxxxxx>
---
v5:
* resolve merge conflict after commit cf23fcc9437e ("net: dsa: mt7530:
add EN7528 support")
* the ATC/VTCR status reads are already regmap_read() via the polling
fixes now in net-next, which also address the read-failure paths
Sashiko flagged on v4
v4:
* zero the read-back buffer in mt7530_regmap_read() instead of
initializing the result variables at every call site
v3:
* init read-back variables to 0 to preserve the old read-failure
behaviour
* use u32 for val in mt7530_setup_port5
v2: drop fix for stray 'static void' leftover now correctly squashed
into 4/8
---
drivers/net/dsa/mt7530-mdio.c | 3 +
drivers/net/dsa/mt7530.c | 113 +++++++++++++++++-----------------
2 files changed, 60 insertions(+), 56 deletions(-)

diff --git a/drivers/net/dsa/mt7530-mdio.c b/drivers/net/dsa/mt7530-mdio.c
index 422f785d2143..81c5c6f7066d 100644
--- a/drivers/net/dsa/mt7530-mdio.c
+++ b/drivers/net/dsa/mt7530-mdio.c
@@ -48,6 +48,9 @@ mt7530_regmap_read(void *context, unsigned int reg, unsigned int *val)
u16 page, r, lo, hi;
int ret;

+ /* Callers do not check for errors, keep the value deterministic */
+ *val = 0;
+
page = (reg >> 6) & 0x3ff;
r = (reg >> 2) & 0xf;

diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
index 0ff8a9eda3e4..57f38d39058a 100644
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -155,28 +155,15 @@ core_clear(struct mt7530_priv *priv, u32 reg, u32 val)
}

static u32
-mt7530_read(struct mt7530_priv *priv, u32 reg)
+mt7530_mii_poll(struct mt7530_dummy_poll *p)
{
- int ret;
u32 val;

- ret = regmap_read(priv->regmap, reg, &val);
- if (ret) {
- WARN_ON_ONCE(1);
- dev_err(priv->dev,
- "failed to read mt7530 register\n");
- return 0;
- }
+ regmap_read(p->priv->regmap, p->reg, &val);

return val;
}

-static u32
-mt7530_mii_poll(struct mt7530_dummy_poll *p)
-{
- return mt7530_read(p->priv, p->reg);
-}
-
static int
mt7530_fdb_cmd(struct mt7530_priv *priv, enum mt7530_fdb_cmd cmd, u32 *rsp)
{
@@ -219,7 +206,8 @@ mt7530_fdb_read(struct mt7530_priv *priv, struct mt7530_fdb *fdb)

/* Read from ARL table into an array */
for (i = 0; i < 3; i++) {
- reg[i] = mt7530_read(priv, MT7530_TSRA1 + (i * 4));
+ regmap_read(priv->regmap, MT7530_TSRA1 + (i * 4),
+ &reg[i]);

dev_dbg(priv->dev, "%s(%d) reg[%d]=0x%x\n",
__func__, __LINE__, i, reg[i]);
@@ -326,7 +314,8 @@ mt7530_setup_port6(struct dsa_switch *ds, phy_interface_t interface)
regmap_update_bits(priv->regmap, MT7530_P6ECR, P6_INTF_MODE_MASK,
P6_INTF_MODE(1));

- xtal = mt7530_read(priv, MT753X_MTRAP) & MT7530_XTAL_MASK;
+ regmap_read(priv->regmap, MT753X_MTRAP, &xtal);
+ xtal &= MT7530_XTAL_MASK;

if (xtal == MT7530_XTAL_25MHZ)
ssc_delta = 0x57;
@@ -370,9 +359,9 @@ mt7531_pll_setup(struct mt7530_priv *priv)
u32 hwstrap;
u32 val;

- val = mt7530_read(priv, MT7531_CREV);
- top_sig = mt7530_read(priv, MT7531_TOP_SIG_SR);
- hwstrap = mt7530_read(priv, MT753X_TRAP);
+ regmap_read(priv->regmap, MT7531_CREV, &val);
+ regmap_read(priv->regmap, MT7531_TOP_SIG_SR, &top_sig);
+ regmap_read(priv->regmap, MT753X_TRAP, &hwstrap);
if ((val & CHIP_REV_M) > 0)
xtal = (top_sig & PAD_MCM_SMI_EN) ? MT7531_XTAL_FSEL_40MHZ :
MT7531_XTAL_FSEL_25MHZ;
@@ -381,26 +370,26 @@ mt7531_pll_setup(struct mt7530_priv *priv)
MT7531_XTAL_FSEL_40MHZ;

/* Step 1 : Disable MT7531 COREPLL */
- val = mt7530_read(priv, MT7531_PLLGP_EN);
+ regmap_read(priv->regmap, MT7531_PLLGP_EN, &val);
val &= ~EN_COREPLL;
regmap_write(priv->regmap, MT7531_PLLGP_EN, val);

/* Step 2: switch to XTAL output */
- val = mt7530_read(priv, MT7531_PLLGP_EN);
+ regmap_read(priv->regmap, MT7531_PLLGP_EN, &val);
val |= SW_CLKSW;
regmap_write(priv->regmap, MT7531_PLLGP_EN, val);

- val = mt7530_read(priv, MT7531_PLLGP_CR0);
+ regmap_read(priv->regmap, MT7531_PLLGP_CR0, &val);
val &= ~RG_COREPLL_EN;
regmap_write(priv->regmap, MT7531_PLLGP_CR0, val);

/* Step 3: disable PLLGP and enable program PLLGP */
- val = mt7530_read(priv, MT7531_PLLGP_EN);
+ regmap_read(priv->regmap, MT7531_PLLGP_EN, &val);
val |= SW_PLLGP;
regmap_write(priv->regmap, MT7531_PLLGP_EN, val);

/* Step 4: program COREPLL output frequency to 500MHz */
- val = mt7530_read(priv, MT7531_PLLGP_CR0);
+ regmap_read(priv->regmap, MT7531_PLLGP_CR0, &val);
val &= ~RG_COREPLL_POSDIV_M;
val |= 2 << RG_COREPLL_POSDIV_S;
regmap_write(priv->regmap, MT7531_PLLGP_CR0, val);
@@ -408,13 +397,13 @@ mt7531_pll_setup(struct mt7530_priv *priv)

switch (xtal) {
case MT7531_XTAL_FSEL_25MHZ:
- val = mt7530_read(priv, MT7531_PLLGP_CR0);
+ regmap_read(priv->regmap, MT7531_PLLGP_CR0, &val);
val &= ~RG_COREPLL_SDM_PCW_M;
val |= 0x140000 << RG_COREPLL_SDM_PCW_S;
regmap_write(priv->regmap, MT7531_PLLGP_CR0, val);
break;
case MT7531_XTAL_FSEL_40MHZ:
- val = mt7530_read(priv, MT7531_PLLGP_CR0);
+ regmap_read(priv->regmap, MT7531_PLLGP_CR0, &val);
val &= ~RG_COREPLL_SDM_PCW_M;
val |= 0x190000 << RG_COREPLL_SDM_PCW_S;
regmap_write(priv->regmap, MT7531_PLLGP_CR0, val);
@@ -422,14 +411,14 @@ mt7531_pll_setup(struct mt7530_priv *priv)
}

/* Set feedback divide ratio update signal to high */
- val = mt7530_read(priv, MT7531_PLLGP_CR0);
+ regmap_read(priv->regmap, MT7531_PLLGP_CR0, &val);
val |= RG_COREPLL_SDM_PCW_CHG;
regmap_write(priv->regmap, MT7531_PLLGP_CR0, val);
/* Wait for at least 16 XTAL clocks */
usleep_range(10, 20);

/* Step 5: set feedback divide ratio update signal to low */
- val = mt7530_read(priv, MT7531_PLLGP_CR0);
+ regmap_read(priv->regmap, MT7531_PLLGP_CR0, &val);
val &= ~RG_COREPLL_SDM_PCW_CHG;
regmap_write(priv->regmap, MT7531_PLLGP_CR0, val);

@@ -440,11 +429,11 @@ mt7531_pll_setup(struct mt7530_priv *priv)
regmap_write(priv->regmap, MT7531_ANA_PLLGP_CR2, 0x4f40000);

/* Step 6: Enable MT7531 PLL */
- val = mt7530_read(priv, MT7531_PLLGP_CR0);
+ regmap_read(priv->regmap, MT7531_PLLGP_CR0, &val);
val |= RG_COREPLL_EN;
regmap_write(priv->regmap, MT7531_PLLGP_CR0, val);

- val = mt7530_read(priv, MT7531_PLLGP_EN);
+ regmap_read(priv->regmap, MT7531_PLLGP_EN, &val);
val |= EN_COREPLL;
regmap_write(priv->regmap, MT7531_PLLGP_EN, val);
usleep_range(25, 35);
@@ -709,11 +698,11 @@ mt7530_read_port_stats(struct mt7530_priv *priv, int port,
{
u32 val, reg = MT7530_PORT_MIB_COUNTER(port) + offset;

- val = mt7530_read(priv, reg);
+ regmap_read(priv->regmap, reg, &val);
*data = val;

if (size == 2) {
- val = mt7530_read(priv, reg + 4);
+ regmap_read(priv->regmap, reg + 4, &val);
*data |= (u64)val << 32;
}
}
@@ -1017,11 +1006,11 @@ static void mt7530_setup_port5(struct dsa_switch *ds, phy_interface_t interface)
{
struct mt7530_priv *priv = ds->priv;
u8 tx_delay = 0;
- int val;
+ u32 val;

mutex_lock(&priv->reg_mutex);

- val = mt7530_read(priv, MT753X_MTRAP);
+ regmap_read(priv->regmap, MT753X_MTRAP, &val);

val &= ~MT7530_P5_PHY0_SEL & ~MT7530_P5_MAC_SEL & ~MT7530_P5_RGMII_MODE;

@@ -1389,7 +1378,7 @@ mt7530_port_change_mtu(struct dsa_switch *ds, int port, int new_mtu)
if (!dsa_is_cpu_port(ds, port))
return 0;

- val = mt7530_read(priv, MT7530_GMACCR);
+ regmap_read(priv->regmap, MT7530_GMACCR, &val);
val &= ~MAX_RX_PKT_LEN_MASK;

/* RX length also includes Ethernet header, MTK tag, and FCS length */
@@ -1802,14 +1791,16 @@ mt7530_port_mdb_add(struct dsa_switch *ds, int port,
const u8 *addr = mdb->addr;
u16 vid = mdb->vid;
u8 port_mask = 0;
+ u32 val;
int ret;

mutex_lock(&priv->reg_mutex);

mt7530_fdb_write(priv, vid, 0, addr, 0, STATIC_EMP);
- if (!mt7530_fdb_cmd(priv, MT7530_FDB_READ, NULL))
- port_mask = (mt7530_read(priv, MT7530_ATRD) >> PORT_MAP)
- & PORT_MAP_MASK;
+ if (!mt7530_fdb_cmd(priv, MT7530_FDB_READ, NULL)) {
+ regmap_read(priv->regmap, MT7530_ATRD, &val);
+ port_mask = (val >> PORT_MAP) & PORT_MAP_MASK;
+ }

port_mask |= BIT(port);
mt7530_fdb_write(priv, vid, port_mask, addr, -1, STATIC_ENT);
@@ -1829,14 +1820,16 @@ mt7530_port_mdb_del(struct dsa_switch *ds, int port,
const u8 *addr = mdb->addr;
u16 vid = mdb->vid;
u8 port_mask = 0;
+ u32 val;
int ret;

mutex_lock(&priv->reg_mutex);

mt7530_fdb_write(priv, vid, 0, addr, 0, STATIC_EMP);
- if (!mt7530_fdb_cmd(priv, MT7530_FDB_READ, NULL))
- port_mask = (mt7530_read(priv, MT7530_ATRD) >> PORT_MAP)
- & PORT_MAP_MASK;
+ if (!mt7530_fdb_cmd(priv, MT7530_FDB_READ, NULL)) {
+ regmap_read(priv->regmap, MT7530_ATRD, &val);
+ port_mask = (val >> PORT_MAP) & PORT_MAP_MASK;
+ }

port_mask &= ~BIT(port);
mt7530_fdb_write(priv, vid, port_mask, addr, -1,
@@ -1914,7 +1907,7 @@ mt7530_hw_vlan_del(struct mt7530_priv *priv,

new_members = entry->old_members & ~BIT(entry->port);

- val = mt7530_read(priv, MT7530_VAWD1);
+ regmap_read(priv->regmap, MT7530_VAWD1, &val);
if (!(val & VLAN_VALID)) {
dev_err(priv->dev,
"Cannot be deleted due to invalid entry\n");
@@ -1941,7 +1934,7 @@ mt7530_hw_vlan_update(struct mt7530_priv *priv, u16 vid,
/* Fetch entry */
mt7530_vlan_cmd(priv, MT7530_VTCR_RD_VID, vid);

- val = mt7530_read(priv, MT7530_VAWD1);
+ regmap_read(priv->regmap, MT7530_VAWD1, &val);

entry->old_members = (val >> PORT_MEM_SHFT) & PORT_MEM_MASK;

@@ -2059,7 +2052,7 @@ static int mt753x_port_mirror_add(struct dsa_switch *ds, int port,
if ((ingress ? priv->mirror_rx : priv->mirror_tx) & BIT(port))
return -EEXIST;

- val = mt7530_read(priv, MT753X_MIRROR_REG(priv->id));
+ regmap_read(priv->regmap, MT753X_MIRROR_REG(priv->id), &val);

/* MT7530 only supports one monitor port */
monitor_port = MT753X_MIRROR_PORT_GET(priv->id, val);
@@ -2072,7 +2065,7 @@ static int mt753x_port_mirror_add(struct dsa_switch *ds, int port,
val |= MT753X_MIRROR_PORT_SET(priv->id, mirror->to_local_port);
regmap_write(priv->regmap, MT753X_MIRROR_REG(priv->id), val);

- val = mt7530_read(priv, MT7530_PCR_P(port));
+ regmap_read(priv->regmap, MT7530_PCR_P(port), &val);
if (ingress) {
val |= PORT_RX_MIR;
priv->mirror_rx |= BIT(port);
@@ -2091,7 +2084,7 @@ static void mt753x_port_mirror_del(struct dsa_switch *ds, int port,
struct mt7530_priv *priv = ds->priv;
u32 val;

- val = mt7530_read(priv, MT7530_PCR_P(port));
+ regmap_read(priv->regmap, MT7530_PCR_P(port), &val);
if (mirror->ingress) {
val &= ~PORT_RX_MIR;
priv->mirror_rx &= ~BIT(port);
@@ -2102,7 +2095,7 @@ static void mt753x_port_mirror_del(struct dsa_switch *ds, int port,
regmap_write(priv->regmap, MT7530_PCR_P(port), val);

if (!priv->mirror_rx && !priv->mirror_tx) {
- val = mt7530_read(priv, MT753X_MIRROR_REG(priv->id));
+ regmap_read(priv->regmap, MT753X_MIRROR_REG(priv->id), &val);
val &= ~MT753X_MIRROR_EN(priv->id);
regmap_write(priv->regmap, MT753X_MIRROR_REG(priv->id), val);
}
@@ -2134,8 +2127,11 @@ mt7530_gpio_get(struct gpio_chip *gc, unsigned int offset)
{
struct mt7530_priv *priv = gpiochip_get_data(gc);
u32 bit = mt7530_gpio_to_bit(offset);
+ u32 val;
+
+ regmap_read(priv->regmap, MT7530_LED_GPIO_DATA, &val);

- return !!(mt7530_read(priv, MT7530_LED_GPIO_DATA) & bit);
+ return !!(val & bit);
}

static int
@@ -2157,8 +2153,11 @@ mt7530_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
{
struct mt7530_priv *priv = gpiochip_get_data(gc);
u32 bit = mt7530_gpio_to_bit(offset);
+ u32 val;

- return (mt7530_read(priv, MT7530_LED_GPIO_DIR) & bit) ?
+ regmap_read(priv->regmap, MT7530_LED_GPIO_DIR, &val);
+
+ return (val & bit) ?
GPIO_LINE_DIRECTION_OUT : GPIO_LINE_DIRECTION_IN;
}

@@ -2449,7 +2448,7 @@ mt7530_setup(struct dsa_switch *ds)
return ret;
}

- id = mt7530_read(priv, MT7530_CREV);
+ regmap_read(priv->regmap, MT7530_CREV, &id);
id >>= CHIP_NAME_SHIFT;
if (id != MT7530_ID) {
dev_err(priv->dev, "chip %x can't be supported\n", id);
@@ -2692,7 +2691,7 @@ mt7531_setup(struct dsa_switch *ds)
return ret;
}

- id = mt7530_read(priv, MT7531_CREV);
+ regmap_read(priv->regmap, MT7531_CREV, &id);
id >>= CHIP_NAME_SHIFT;

if (id != MT7531_ID) {
@@ -2703,7 +2702,7 @@ mt7531_setup(struct dsa_switch *ds)
/* MT7531AE has got two SGMII units. One for port 5, one for port 6.
* MT7531BE has got only one SGMII unit which is for port 6.
*/
- val = mt7530_read(priv, MT7531_TOP_SIG_SR);
+ regmap_read(priv->regmap, MT7531_TOP_SIG_SR, &val);
priv->p5_sgmii = !!(val & PAD_DUAL_SGMII_EN);

/* Force link down on all ports before internal reset */
@@ -2923,7 +2922,7 @@ static void mt7531_rgmii_setup(struct mt7530_priv *priv,
{
u32 val;

- val = mt7530_read(priv, MT7531_CLKGEN_CTRL);
+ regmap_read(priv->regmap, MT7531_CLKGEN_CTRL, &val);
val |= GP_CLK_EN;
val &= ~GP_MODE_MASK;
val |= GP_MODE(MT7531_GP_MODE_RGMII);
@@ -3106,7 +3105,9 @@ static void mt753x_phylink_get_caps(struct dsa_switch *ds, int port,
* userspace.
*/
if (priv->id != ID_EN7528) {
- u32 eeecr = mt7530_read(priv, MT753X_PMEEECR_P(port));
+ u32 eeecr;
+
+ regmap_read(priv->regmap, MT753X_PMEEECR_P(port), &eeecr);

config->lpi_capabilities = MAC_100FD | MAC_1000FD | MAC_2500FD;
/* tx_lpi_timer should be in microseconds. The time units for
@@ -3137,7 +3138,7 @@ static void mt7530_pcs_get_state(struct phylink_pcs *pcs, unsigned int neg_mode,
int port = pcs_to_mt753x_pcs(pcs)->port;
u32 pmsr;

- pmsr = mt7530_read(priv, MT7530_PMSR_P(port));
+ regmap_read(priv->regmap, MT7530_PMSR_P(port), &pmsr);

state->link = (pmsr & PMSR_LINK);
state->an_complete = state->link;
--
2.55.0