From c3953a3c2d3175d2f9f0304c9a1ba89e7743c5e4 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Mon, 5 Aug 2019 12:00:55 +0200 Subject: [PATCH] NFC: nfcmrvl: fix gpio-handling regression Fix two reset-gpio sanity checks which were never converted to use gpio_is_valid(), and make sure to use -EINVAL to indicate a missing reset line also for the UART-driver module parameter and for the USB driver. This specifically prevents the UART and USB drivers from incidentally trying to request and use gpio 0, and also avoids triggering a WARN() in gpio_to_desc() during probe when no valid reset line has been specified. Fixes: e33a3f84f88f ("NFC: nfcmrvl: allow gpio 0 for reset signalling") Reported-by: syzbot+cf35b76f35e068a1107f@syzkaller.appspotmail.com Tested-by: syzbot+cf35b76f35e068a1107f@syzkaller.appspotmail.com Signed-off-by: Johan Hovold --- drivers/nfc/nfcmrvl/main.c | 4 ++-- drivers/nfc/nfcmrvl/uart.c | 4 ++-- drivers/nfc/nfcmrvl/usb.c | 1 + 3 files changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/nfc/nfcmrvl/main.c b/drivers/nfc/nfcmrvl/main.c index e65d027b91fa..529be35ac178 100644 --- a/drivers/nfc/nfcmrvl/main.c +++ b/drivers/nfc/nfcmrvl/main.c @@ -244,7 +244,7 @@ void nfcmrvl_chip_reset(struct nfcmrvl_private *priv) /* Reset possible fault of previous session */ clear_bit(NFCMRVL_PHY_ERROR, &priv->flags); - if (priv->config.reset_n_io) { + if (gpio_is_valid(priv->config.reset_n_io)) { nfc_info(priv->dev, "reset the chip\n"); gpio_set_value(priv->config.reset_n_io, 0); usleep_range(5000, 10000); @@ -255,7 +255,7 @@ void nfcmrvl_chip_reset(struct nfcmrvl_private *priv) void nfcmrvl_chip_halt(struct nfcmrvl_private *priv) { - if (priv->config.reset_n_io) + if (gpio_is_valid(priv->config.reset_n_io)) gpio_set_value(priv->config.reset_n_io, 0); } diff --git a/drivers/nfc/nfcmrvl/uart.c b/drivers/nfc/nfcmrvl/uart.c index 9a22056e8d9e..e5a622ce4b95 100644 --- a/drivers/nfc/nfcmrvl/uart.c +++ b/drivers/nfc/nfcmrvl/uart.c @@ -26,7 +26,7 @@ static unsigned int hci_muxed; static unsigned int flow_control; static unsigned int break_control; -static unsigned int reset_n_io; +static int reset_n_io = -EINVAL; /* ** NFCMRVL NCI OPS @@ -231,5 +231,5 @@ MODULE_PARM_DESC(break_control, "Tell if UART driver must drive break signal."); module_param(hci_muxed, uint, 0); MODULE_PARM_DESC(hci_muxed, "Tell if transport is muxed in HCI one."); -module_param(reset_n_io, uint, 0); +module_param(reset_n_io, int, 0); MODULE_PARM_DESC(reset_n_io, "GPIO that is wired to RESET_N signal."); diff --git a/drivers/nfc/nfcmrvl/usb.c b/drivers/nfc/nfcmrvl/usb.c index 945cc903d8f1..888e298f610b 100644 --- a/drivers/nfc/nfcmrvl/usb.c +++ b/drivers/nfc/nfcmrvl/usb.c @@ -305,6 +305,7 @@ static int nfcmrvl_probe(struct usb_interface *intf, /* No configuration for USB */ memset(&config, 0, sizeof(config)); + config.reset_n_io = -EINVAL; nfc_info(&udev->dev, "intf %p id %p\n", intf, id);