Commit 1c184bac authored by Joy Chakraborty's avatar Joy Chakraborty Committed by Alexandre Belloni
Browse files

rtc: cmos: Fix return value of nvmem callbacks 



Read/write callbacks registered with nvmem core expect 0 to be returned
on success and a negative value to be returned on failure.

cmos_nvram_read()/cmos_nvram_write() currently return the number of
bytes read or written, fix to return 0 on success and -EIO incase number
of bytes requested was not read or written.

Fixes: 8b5b7958 ("rtc: cmos: use generic nvmem")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarJoy Chakraborty <joychakr@google.com>
Reviewed-by: default avatarDan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/20240612083635.1253039-1-joychakr@google.com


Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@bootlin.com>
parent 70f1ae5f

drivers/rtc/rtc-cmos.c

+4 −6
Original line number Diff line number Diff line
@@ -643,11 +643,10 @@ static int cmos_nvram_read(void *priv, unsigned int off, void *val, 
			   size_t count)

{

	unsigned char *buf = val;

	int	retval;



	off += NVRAM_OFFSET;

	spin_lock_irq(&rtc_lock);

	for (retval = 0; count; count--, off++, retval++) {

	for (; count; count--, off++) {

		if (off < 128)

			*buf++ = CMOS_READ(off);

		else if (can_bank2)
@@ -657,7 +656,7 @@ static int cmos_nvram_read(void *priv, unsigned int off, void *val, 
	}

	spin_unlock_irq(&rtc_lock);



	return retval;

	return count ? -EIO : 0;

}



static int cmos_nvram_write(void *priv, unsigned int off, void *val,
@@ -665,7 +664,6 @@ static int cmos_nvram_write(void *priv, unsigned int off, void *val, 
{

	struct cmos_rtc	*cmos = priv;

	unsigned char	*buf = val;

	int		retval;



	/* NOTE:  on at least PCs and Ataris, the boot firmware uses a

	 * checksum on part of the NVRAM data.  That's currently ignored
@@ -674,7 +672,7 @@ static int cmos_nvram_write(void *priv, unsigned int off, void *val, 
	 */

	off += NVRAM_OFFSET;

	spin_lock_irq(&rtc_lock);

	for (retval = 0; count; count--, off++, retval++) {

	for (; count; count--, off++) {

		/* don't trash RTC registers */

		if (off == cmos->day_alrm

				|| off == cmos->mon_alrm
@@ -689,7 +687,7 @@ static int cmos_nvram_write(void *priv, unsigned int off, void *val, 
	}

	spin_unlock_irq(&rtc_lock);



	return retval;

	return count ? -EIO : 0;

}



/*----------------------------------------------------------------*/