| Message ID | 20211229003729.618079-1-colin.foster@in-advantage.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | add blink and activity functions to SGPIO | expand |
On Tue, Dec 28, 2021 at 04:37:28PM -0800, Colin Foster wrote: > Expose a debugfs / devicetree interface for Microsemi SGPIO controllers. > By writing values of 2-5, the SGPIO pins can be configured for either > automatic blinking or activity. > > The implementation is modeled after the code in > /drivers/pinctrl/pinctrl-ocelot.c. > > I have only tested this with currently out-of-tree patches for the > VSC7512 that I hope to get in soon. They are not needed for VSC7513 / > VSC7514, SPARX5, or LUTON - but I don't have any hardware to test. > > Of note: the 7512 chip has a discrepancy between the datasheet and the > registers. The datahseet claims 20Hz blink default frequency, the > registers claim 5 Hz default frequency for BMODE_0. I override the > OCELOT registers to correct for this. I don't know if that is needed for > LUTON or SPARX, but having two blink modes at the same frequency isn't > beneficial. As such, I make the blink modes match the 5Hz / 20Hz for the > two modes. > > Tested with VSC7512 by way of: > echo SGPIO_O_p1b0 {blink0,blink1,activity0,activity1} > > /sys/kernel/debug/pinctrl/pinctrl-sgpio-pinctrl-sgpio-output/pinmux-select Hi Colin Since this is an LED, you should be using the Linux LED interface in /sys/class/leds. See Documentation/leds/leds-class.rst. It includes a way to make an LED blink, using hardware. Activity is another story. I assume you mean Ethernet frame Rx and Tx? For that you should wait until the Ethernet LED offload code eventually lands. Andrew
On Wed, Dec 29, 2021 at 10:30:54AM +0100, Andrew Lunn wrote: > On Tue, Dec 28, 2021 at 04:37:28PM -0800, Colin Foster wrote: > > Expose a debugfs / devicetree interface for Microsemi SGPIO controllers. > > By writing values of 2-5, the SGPIO pins can be configured for either > > automatic blinking or activity. > > > > The implementation is modeled after the code in > > /drivers/pinctrl/pinctrl-ocelot.c. > > > > I have only tested this with currently out-of-tree patches for the > > VSC7512 that I hope to get in soon. They are not needed for VSC7513 / > > VSC7514, SPARX5, or LUTON - but I don't have any hardware to test. > > > > Of note: the 7512 chip has a discrepancy between the datasheet and the > > registers. The datahseet claims 20Hz blink default frequency, the > > registers claim 5 Hz default frequency for BMODE_0. I override the > > OCELOT registers to correct for this. I don't know if that is needed for > > LUTON or SPARX, but having two blink modes at the same frequency isn't > > beneficial. As such, I make the blink modes match the 5Hz / 20Hz for the > > two modes. > > > > Tested with VSC7512 by way of: > > echo SGPIO_O_p1b0 {blink0,blink1,activity0,activity1} > > > /sys/kernel/debug/pinctrl/pinctrl-sgpio-pinctrl-sgpio-output/pinmux-select > > Hi Colin > > Since this is an LED, you should be using the Linux LED interface in > /sys/class/leds. See Documentation/leds/leds-class.rst. It includes a > way to make an LED blink, using hardware. Hi Andrew, With the static LEDs that is exactly how I have them configured. I was happy when they all "just worked" when I tied them to the phy activity. My thanks to all those who did this hard work before me! I have noticed an issue in my setup where using a heartbeat trigger on any of the outputs causes a kernel bug "scheduling while atomic." It seems to be trying to interrupt spi_sync... Sorry, I'm getting off track, and I'll deal with that in time. Luckily it is very reproducable! > > Activity is another story. I assume you mean Ethernet frame Rx and Tx? > For that you should wait until the Ethernet LED offload code > eventually lands. I've been following those threads a little bit. Seemingly a few emails between August and November. I suspect it'll require at least some version of this patch, but it is probably best to wait and see where that lands first. Thanks! > > Andrew
Expose a debugfs / devicetree interface for Microsemi SGPIO controllers. By writing values of 2-5, the SGPIO pins can be configured for either automatic blinking or activity. The implementation is modeled after the code in /drivers/pinctrl/pinctrl-ocelot.c. I have only tested this with currently out-of-tree patches for the VSC7512 that I hope to get in soon. They are not needed for VSC7513 / VSC7514, SPARX5, or LUTON - but I don't have any hardware to test. Of note: the 7512 chip has a discrepancy between the datasheet and the registers. The datahseet claims 20Hz blink default frequency, the registers claim 5 Hz default frequency for BMODE_0. I override the OCELOT registers to correct for this. I don't know if that is needed for LUTON or SPARX, but having two blink modes at the same frequency isn't beneficial. As such, I make the blink modes match the 5Hz / 20Hz for the two modes. Tested with VSC7512 by way of: echo SGPIO_O_p1b0 {blink0,blink1,activity0,activity1} > /sys/kernel/debug/pinctrl/pinctrl-sgpio-pinctrl-sgpio-output/pinmux-select LEDs blink! Colin Foster (1): pinctrl: microchip-sgpio: add activity and blink functionality drivers/pinctrl/pinctrl-microchip-sgpio.c | 135 +++++++++++++++++++++- 1 file changed, 130 insertions(+), 5 deletions(-)