5.15-stable review patch. If anyone has any objections, please let me know.
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From: Joy Chakraborty joychakr@google.com
commit 1c184baccf0d5e2ef4cc1562261d0e48508a1c2b upstream.
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: 8b5b7958fd1c ("rtc: cmos: use generic nvmem") Cc: stable@vger.kernel.org Signed-off-by: Joy Chakraborty joychakr@google.com Reviewed-by: Dan Carpenter dan.carpenter@linaro.org Link: https://lore.kernel.org/r/20240612083635.1253039-1-joychakr@google.com Signed-off-by: Alexandre Belloni alexandre.belloni@bootlin.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/rtc/rtc-cmos.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-)
--- a/drivers/rtc/rtc-cmos.c +++ b/drivers/rtc/rtc-cmos.c @@ -643,11 +643,10 @@ static int cmos_nvram_read(void *priv, u 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, u } 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, { 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, */ 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, } spin_unlock_irq(&rtc_lock);
- return retval; + return count ? -EIO : 0; }
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