From 5edc8c687357b40469d90e3dab0b59b72eaabf59 Mon Sep 17 00:00:00 2001 From: Ahmad Fatoum Date: Thu, 11 Jun 2020 21:17:46 +0200 Subject: watchdog: f71808e_wdt: do stricter parameter validation We check the f71862fg_pin module parameter every time a watchdog device for the f71862fg is opened, but the parameter can't change at runtime. If we move the check to the start of init: - We catch userspace passing invalid, but unused, values - We check the condition only once - We simplify the code Do so. Signed-off-by: Ahmad Fatoum Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20200611191750.28096-6-a.fatoum@pengutronix.de Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- drivers/watchdog/f71808e_wdt.c | 37 ++++++++++++------------------------- 1 file changed, 12 insertions(+), 25 deletions(-) (limited to 'drivers/watchdog') diff --git a/drivers/watchdog/f71808e_wdt.c b/drivers/watchdog/f71808e_wdt.c index 26bf366aebc2..9f7823819ed1 100644 --- a/drivers/watchdog/f71808e_wdt.c +++ b/drivers/watchdog/f71808e_wdt.c @@ -306,27 +306,6 @@ exit_unlock: return err; } -static int f71862fg_pin_configure(unsigned short ioaddr) -{ - /* When ioaddr is non-zero the calling function has to take care of - mutex handling and superio preparation! */ - - if (f71862fg_pin == 63) { - if (ioaddr) { - /* SPI must be disabled first to use this pin! */ - superio_clear_bit(ioaddr, SIO_REG_ROM_ADDR_SEL, 6); - superio_set_bit(ioaddr, SIO_REG_MFUNCT3, 4); - } - } else if (f71862fg_pin == 56) { - if (ioaddr) - superio_set_bit(ioaddr, SIO_REG_MFUNCT1, 1); - } else { - pr_err("Invalid argument f71862fg_pin=%d\n", f71862fg_pin); - return -EINVAL; - } - return 0; -} - static int watchdog_start(void) { int err; @@ -352,9 +331,13 @@ static int watchdog_start(void) break; case f71862fg: - err = f71862fg_pin_configure(watchdog.sioaddr); - if (err) - goto exit_superio; + if (f71862fg_pin == 63) { + /* SPI must be disabled first to use this pin! */ + superio_clear_bit(watchdog.sioaddr, SIO_REG_ROM_ADDR_SEL, 6); + superio_set_bit(watchdog.sioaddr, SIO_REG_MFUNCT3, 4); + } else if (f71862fg_pin == 56) { + superio_set_bit(watchdog.sioaddr, SIO_REG_MFUNCT1, 1); + } break; case f71868: @@ -810,7 +793,6 @@ static int __init f71808e_find(int sioaddr) break; case SIO_F71862_ID: watchdog.type = f71862fg; - err = f71862fg_pin_configure(0); /* validate module parameter */ break; case SIO_F71868_ID: watchdog.type = f71868; @@ -859,6 +841,11 @@ static int __init f71808e_init(void) int err = -ENODEV; int i; + if (f71862fg_pin != 63 && f71862fg_pin != 56) { + pr_err("Invalid argument f71862fg_pin=%d\n", f71862fg_pin); + return -EINVAL; + } + for (i = 0; i < ARRAY_SIZE(addrs); i++) { err = f71808e_find(addrs[i]); if (err == 0) -- cgit v1.2.3