[PATCH net-next v3 2/6] net: phy: microchip_t1s: replace read-modify-write code with phy_modify_mmd

Parthiban Veerasooran
2023-05-24T14:44:48Z

Replace read-modify-write code in the lan867x_config_init function to
avoid handling data type mismatch and to simplify the code.

Signed-off-by: Parthiban Veerasooran <Parthiban.Veerasooran@microchip.com>
---
drivers/net/phy/microchip_t1s.c | 23 +++++++++++------------
1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/drivers/net/phy/microchip_t1s.c b/drivers/net/phy/microchip_t1s.c
index a42a6bb6e3bd..b5b5a95fa6e7 100644
--- a/drivers/net/phy/microchip_t1s.c
+++ b/drivers/net/phy/microchip_t1s.c
@@ -31,19 +31,19 @@
* W 0x1F 0x0099 0x7F80 ------
*/

-static const int lan867x_fixup_registers[12] = {
+static const u32 lan867x_fixup_registers[12] = {
0x00D0, 0x00D1, 0x0084, 0x0085,
0x008A, 0x0087, 0x0088, 0x008B,
0x0080, 0x00F1, 0x0096, 0x0099,
};

-static const int lan867x_fixup_values[12] = {
+static const u16 lan867x_fixup_values[12] = {
0x0002, 0x0000, 0x3380, 0x0006,
0xC000, 0x801C, 0x033F, 0x0404,
0x0600, 0x2400, 0x2000, 0x7F80,
};

-static const int lan867x_fixup_masks[12] = {
+static const u16 lan867x_fixup_masks[12] = {
0x0E03, 0x0300, 0xFFC0, 0x000F,
0xF800, 0x801C, 0x1FFF, 0xFFFF,
0x0600, 0x7F00, 0x2000, 0xFFFF,
@@ -63,23 +63,22 @@ static int lan867x_config_init(struct phy_device *phydev)
* used, which might then write the same value back as read + modified.
*/

- int reg_value;
int err;
- int reg;

/* Read-Modified Write Pseudocode (from AN1699)
* current_val = read_register(mmd, addr) // Read current register value
* new_val = current_val AND (NOT mask) // Clear bit fields to be written
* new_val = new_val OR value // Set bits
- * write_register(mmd, addr, new_val) // Write back updated register value
+ * write_register(mmd, addr, new_val) // Write back updated register value.
+ * Although AN1699 says Read, Modify, Write, the write is not required if
+ * the register already has the required value.
*/
for (int i = 0; i < ARRAY_SIZE(lan867x_fixup_registers); i++) {
- reg = lan867x_fixup_registers[i];
- reg_value = phy_read_mmd(phydev, MDIO_MMD_VEND2, reg);
- reg_value &= ~lan867x_fixup_masks[i];
- reg_value |= lan867x_fixup_values[i];
- err = phy_write_mmd(phydev, MDIO_MMD_VEND2, reg, reg_value);
- if (err != 0)
+ err = phy_modify_mmd(phydev, MDIO_MMD_VEND2,
+ lan867x_fixup_registers[i],
+ lan867x_fixup_masks[i],
+ lan867x_fixup_values[i]);
+ if (err)
return err;
}

--
2.34.1