fpga-manager: altera-ps-spi: preserve nCONFIG state

From: Anatolij Gustschin <[email protected]>

If the driver module is loaded when FPGA is configured, the FPGA is reset because nconfig is pulled low (low-active gpio inited with GPIOD_OUT_HIGH activates the signal which means setting its value to low). Init nconfig with GPIOD_OUT_LOW to prevent this.

---

Hi Greg,

as discussed. Can you please take this bugfix for 4.17? I rebased it against next.

Thanks,

Moritz

PS: Sorry for late submission

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 drivers/fpga/altera-ps-spi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index 14f14efdf0d5..06d212a3d49d 100644
@@ -249,7 +249,7 @@ static int altera_ps_probe(struct spi_device *spi)
 
 	conf->data = of_id->data;
 	conf->spi = spi;
-	conf->config = devm_gpiod_get(&spi->dev, "nconfig", GPIOD_OUT_HIGH);
+	conf->config = devm_gpiod_get(&spi->dev, "nconfig", GPIOD_OUT_LOW);
 	if (IS_ERR(conf->config)) {
 		dev_err(&spi->dev, "Failed to get config gpio: %ld\n",
 			PTR_ERR(conf->config));

2.17.0

Is it also needed in any older kernel versions?

thanks,

greg k-h

On Mon, 16 Apr 2018 10:10:08 +0200
Greg KH [email protected] wrote:
...

It is needed in versions starting from v4.14.

thanks,

Anatolij