[PATCH 4.14 76/91] fpga-manager: altera-ps-spi: preserve nCONFIG state

From: Greg Kroah-Hartman
Date: Mon Apr 30 2018 - 16:02:29 EST

4.14-stable review patch. If anyone has any objections, please let me know.


From: Anatolij Gustschin <agust@xxxxxxx>

commit 881c93c0fb73328845898344208fa0bf0d62cac6 upstream.

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.

Signed-off-by: Anatolij Gustschin <agust@xxxxxxx>
Acked-by: Alan Tull <atull@xxxxxxxxxx>
Signed-off-by: Moritz Fischer <mdf@xxxxxxxxxx>
Cc: stable <stable@xxxxxxxxxxxxxxx> # 4.14+
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

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

--- a/drivers/fpga/altera-ps-spi.c
+++ b/drivers/fpga/altera-ps-spi.c
@@ -249,7 +249,7 @@ static int altera_ps_probe(struct spi_de

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",