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: e33a3f84f8 ("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 <johan@kernel.org>
This commit is contained in:
Johan Hovold 2019-08-05 12:00:55 +02:00 committed by David S. Miller
parent 5e5412c365
commit c3953a3c2d
3 changed files with 5 additions and 4 deletions

View File

@ -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);
}

View File

@ -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.");

View File

@ -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);