From: <Tudor.Ambarus@microchip.com> To: <michael@walle.cc>, <linux-mtd@lists.infradead.org>, <linux-kernel@vger.kernel.org> Cc: <miquel.raynal@bootlin.com>, <richard@nod.at>, <vigneshr@ti.com>, <linux@roeck-us.net> Subject: Re: [PATCH] mtd: core: handle flashes without OTP gracefully Date: Sat, 3 Jul 2021 16:42:30 +0000 [thread overview] Message-ID: <8da3d84e-dfbf-2030-98b4-148362d22f52@microchip.com> (raw) In-Reply-To: <9F46D75C-D00D-4577-A337-7411049EC7D9@walle.cc> On 7/3/21 7:08 PM, Michael Walle wrote: > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > > 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 why? :D > > >>> 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. I've thought about: diff --git a/drivers/mtd/chips/cfi_cmdset_0001.c b/drivers/mtd/chips/cfi_cmdset_0001.c index 54f92d09d9cf..9419b33d7238 100644 --- a/drivers/mtd/chips/cfi_cmdset_0001.c +++ b/drivers/mtd/chips/cfi_cmdset_0001.c @@ -2314,7 +2314,7 @@ static int cfi_intelext_otp_walk(struct mtd_info *mtd, loff_t from, size_t len, /* Check that we actually have some OTP registers */ if (!extp || !(extp->FeatureSupport & 64) || !extp->NumProtectionFields) - return -ENODATA; + return 0; > > -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/ >>> >
WARNING: multiple messages have this Message-ID (diff)
From: <Tudor.Ambarus@microchip.com> To: <michael@walle.cc>, <linux-mtd@lists.infradead.org>, <linux-kernel@vger.kernel.org> Cc: <miquel.raynal@bootlin.com>, <richard@nod.at>, <vigneshr@ti.com>, <linux@roeck-us.net> Subject: Re: [PATCH] mtd: core: handle flashes without OTP gracefully Date: Sat, 3 Jul 2021 16:42:30 +0000 [thread overview] Message-ID: <8da3d84e-dfbf-2030-98b4-148362d22f52@microchip.com> (raw) In-Reply-To: <9F46D75C-D00D-4577-A337-7411049EC7D9@walle.cc> On 7/3/21 7:08 PM, Michael Walle wrote: > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > > 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 why? :D > > >>> 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. I've thought about: diff --git a/drivers/mtd/chips/cfi_cmdset_0001.c b/drivers/mtd/chips/cfi_cmdset_0001.c index 54f92d09d9cf..9419b33d7238 100644 --- a/drivers/mtd/chips/cfi_cmdset_0001.c +++ b/drivers/mtd/chips/cfi_cmdset_0001.c @@ -2314,7 +2314,7 @@ static int cfi_intelext_otp_walk(struct mtd_info *mtd, loff_t from, size_t len, /* Check that we actually have some OTP registers */ if (!extp || !(extp->FeatureSupport & 64) || !extp->NumProtectionFields) - return -ENODATA; + return 0; > > -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/ >>> > ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/
next prev parent reply other threads:[~2021-07-03 16:42 UTC|newest] Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-07-02 9:38 [PATCH] mtd: core: handle flashes without OTP gracefully Michael Walle 2021-07-02 9:38 ` Michael Walle 2021-07-02 13:49 ` Guenter Roeck 2021-07-02 13:49 ` Guenter Roeck 2021-07-02 13:53 ` Michael Walle 2021-07-02 13:53 ` Michael Walle 2021-07-03 9:56 ` Tudor.Ambarus 2021-07-03 9:56 ` Tudor.Ambarus 2021-07-03 16:08 ` Michael Walle 2021-07-03 16:08 ` Michael Walle 2021-07-03 16:42 ` Tudor.Ambarus [this message] 2021-07-03 16:42 ` Tudor.Ambarus 2021-07-03 17:26 ` Guenter Roeck 2021-07-03 17:26 ` Guenter Roeck 2021-07-06 16:29 ` Miquel Raynal 2021-07-06 16:29 ` Miquel Raynal 2021-07-06 18:22 ` Guenter Roeck 2021-07-06 18:22 ` Guenter Roeck
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=8da3d84e-dfbf-2030-98b4-148362d22f52@microchip.com \ --to=tudor.ambarus@microchip.com \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-mtd@lists.infradead.org \ --cc=linux@roeck-us.net \ --cc=michael@walle.cc \ --cc=miquel.raynal@bootlin.com \ --cc=richard@nod.at \ --cc=vigneshr@ti.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.