Messages in this thread | | | Date | Sat, 03 Jul 2021 18:08:38 +0200 | Subject | Re: [PATCH] mtd: core: handle flashes without OTP gracefully | From | Michael Walle <> |
| |
Am 3. Juli 2021 11:56:14 MESZ schrieb Tudor.Ambarus@microchip.com: >On 7/2/21 12:38 PM, Michael Walle wrote: >> EXTERNAL EMAIL: Do not click links or open attachments unless you >know the content is safe >> >> There are flash drivers which registers the OTP callbacks although >the >> flash doesn't support OTP regions and return -ENODATA for these >> callbacks if there is no OTP. If this happens, the probe of the whole > >why do they register the OTP callback if they don't support OTP?
I don't know. But I certainly won't touch that code :p
>> flash will fail. Fix it by handling the ENODATA return code and skip >> the OTP region nvmem setup. >> >> Fixes: 4b361cfa8624 ("mtd: core: add OTP nvmem provider support") >> Reported-by: Guenter Roeck <linux@roeck-us.net> >> Signed-off-by: Michael Walle <michael@walle.cc> >> --- >> drivers/mtd/mtdcore.c | 10 ++++++++-- >> 1 file changed, 8 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c >> index b5ccd3037788..6881d1423dd6 100644 >> --- a/drivers/mtd/mtdcore.c >> +++ b/drivers/mtd/mtdcore.c >> @@ -880,7 +880,10 @@ static int mtd_otp_nvmem_add(struct mtd_info >*mtd) >> >> if (mtd->_get_user_prot_info && mtd->_read_user_prot_reg) { >> size = mtd_otp_size(mtd, true); >> - if (size < 0) >> + /* ENODATA means there is no OTP region */ >> + if (size == -ENODATA) > >If no OTP data, maybe it's more appropriate for the clients to just >return a retlen of 0.
you mean already checking ENODATA in mtd_otp_size() and return 0. That would also make the hunk below unnecessary. I'll change it.
-michael
> > >> + size = 0; >> + else if (size < 0) >> return size; >> >> if (size > 0) { >> @@ -896,7 +899,10 @@ static int mtd_otp_nvmem_add(struct mtd_info >*mtd) >> >> if (mtd->_get_fact_prot_info && mtd->_read_fact_prot_reg) { >> size = mtd_otp_size(mtd, false); >> - if (size < 0) { >> + /* ENODATA means there is no OTP region */ >> + if (size == -ENODATA) { >> + size = 0; >> + } else if (size < 0) { >> err = size; >> goto err; >> } >> -- >> 2.20.1 >> >> >> ______________________________________________________ >> Linux MTD discussion mailing list >> http://lists.infradead.org/mailman/listinfo/linux-mtd/ >>
| |