| Message ID | 20250113-dp83822-tx-swing-v1-0-7ed5a9d80010@liebherr.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | net: phy: dp83822: Add support for changing the transmit amplitude voltage | expand |
On Mon, Jan 13, 2025 at 06:40:11AM +0100, Dimitri Fedrau via B4 Relay wrote: > Add support for changing the transmit amplitude voltage in 100BASE-TX mode. > Add support for configuration via DT. The commit message is supposed to answer the question "Why?". Isn't reducing the voltage going to make the device non conforming? Why would i want to break it? I could understand setting it a bit higher than required to handle losses on the PCB and connector, so the voltages measured on the RJ45 pins are conforming. Also, what makes the dp8382 special? I know other PHYs can actually do this. So why are we adding some vendor specific property just for 100base-tx? Andrew
Hi Andrew, Am Mon, Jan 13, 2025 at 02:54:28PM +0100 schrieb Andrew Lunn: > On Mon, Jan 13, 2025 at 06:40:11AM +0100, Dimitri Fedrau via B4 Relay wrote: > > Add support for changing the transmit amplitude voltage in 100BASE-TX mode. > > Add support for configuration via DT. > > The commit message is supposed to answer the question "Why?". Isn't > reducing the voltage going to make the device non conforming? Why > would i want to break it? I could understand setting it a bit higher > than required to handle losses on the PCB and connector, so the > voltages measured on the RJ45 pins are conforming. > - Will add the "Why?" to the commit description. You already answered it. - Yes you are right. - I don't want to break it, the PHY just provides these settings. And I just wanted to reflect this in the code, although it probably doesn't make sense. - In my case I want to set it a bit higher to be conforming. > Also, what makes the dp8382 special? I know other PHYs can actually do > this. So why are we adding some vendor specific property just for > 100base-tx? > I don't think that the dp83822 is special in this case. I just didn't know better. Would be removing the vendor specific property enough ? Or is there already a defined property describing this. Didn't found anything. Best regards, Dimitri
Add support for changing the transmit amplitude voltage in 100BASE-TX mode. Add support for configuration via DT. Signed-off-by: Dimitri Fedrau <dimitri.fedrau@liebherr.com> --- Dimitri Fedrau (2): dt-bindings: net: dp83822: Add support for changing the transmit amplitude voltage net: phy: dp83822: Add support for changing the transmit amplitude voltage .../devicetree/bindings/net/ti,dp83822.yaml | 11 +++++++ drivers/net/phy/dp83822.c | 35 ++++++++++++++++++++++ 2 files changed, 46 insertions(+) --- base-commit: 7d0da8f862340c5f42f0062b8560b8d0971a6ac4 change-id: 20241213-dp83822-tx-swing-5ba6c1e9b065 Best regards,