From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.free-electrons.com ([62.4.15.54]) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1cWQnJ-0002ZR-OP for linux-mtd@lists.infradead.org; Wed, 25 Jan 2017 16:51:39 +0000 Date: Wed, 25 Jan 2017 17:51:05 +0100 From: Boris Brezillon To: =?UTF-8?B?Q8OpZHJpYw==?= Le Goater Cc: linux-mtd@lists.infradead.org, David Woodhouse , Brian Norris , Marek Vasut , Richard Weinberger , Cyrille Pitchen , devicetree@vger.kernel.org, Rob Herring , Mark Rutland Subject: Re: [PATCH 1/3] mtd: name the mtd device with an optional label property Message-ID: <20170125175105.67c335e7@bbrezillon> In-Reply-To: <7bdf47c3-d3b7-92a2-47c1-99e4bd6b4f44@kaod.org> References: <1484573225-19095-1-git-send-email-clg@kaod.org> <1484573225-19095-2-git-send-email-clg@kaod.org> <20170124151353.5bbffae0@bbrezillon> <7bdf47c3-d3b7-92a2-47c1-99e4bd6b4f44@kaod.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, 25 Jan 2017 17:47:13 +0100 C=C3=A9dric Le Goater wrote: > On 01/24/2017 03:13 PM, Boris Brezillon wrote: > > Hi C=C3=A9dric, > >=20 > > On Mon, 16 Jan 2017 14:27:03 +0100 > > C=C3=A9dric Le Goater wrote: > > =20 > >> This can be used to easily identify a specific chip on a system with > >> multiple chips. > >> > >> Suggested-by: Boris Brezillon > >> Signed-off-by: C=C3=A9dric Le Goater > >> --- > >> drivers/mtd/mtdcore.c | 7 +++++++ > >> 1 file changed, 7 insertions(+) > >> > >> diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c > >> index 052772f7caef..bf61557b599d 100644 > >> --- a/drivers/mtd/mtdcore.c > >> +++ b/drivers/mtd/mtdcore.c > >> @@ -654,6 +654,13 @@ static int mtd_add_device_partitions(struct mtd_i= nfo *mtd, > >> */ > >> static void mtd_set_dev_defaults(struct mtd_info *mtd) > >> { > >> + /* > >> + * If DT support is enabled and we have a valid of_node pointer, try= to > >> + * extract the MTD name from the label property. > >> + */ > >> + if (IS_ENABLED(CONFIG_OF) && mtd->dev.of_node) > >> + of_property_read_string(mtd->dev.of_node, "label", &mtd->name); > >> + =20 > >=20 > > I realize this kind of thing would be better placed in mtd_set_of_node() > > (see the patch below). Modifying the mtd->name pointer in the back of > > MTD drivers is not such a good idea (suppose the driver allocated the > > memory with a regular kmalloc() and tries to free mtd->name in the remo= ve > > path). > >=20 > > If we move that to mtd_set_of_node(), drivers that wants to support this > > label property just have to check if mtd->name is NULL (after calling > > mtd_set_of_node() or nand_set_flash_node()) before assigning a default > > name. > > For unmodified drivers we keep the existing behavior: they'll just > > unconditionally override mtd->name with their own value (which might or > > might not be dynamically allocated). =20 >=20 > ok. So the expected behavior looks correct to me, but adding a call to=20 > of_property_read_string() in the inline below feels a little hacky.=20 > Doesn't it ?=20 >=20 > May be we need an extra check on IS_ENABLED(CONFIG_OF) also ?=20 This is all safe, because the of.h header defines stubs if CONFIG_OF is not set. That just means the name will be unchanged, but you shouldn't have any problem (neither as compilation time nor at runtime). From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boris Brezillon Subject: Re: [PATCH 1/3] mtd: name the mtd device with an optional label property Date: Wed, 25 Jan 2017 17:51:05 +0100 Message-ID: <20170125175105.67c335e7@bbrezillon> References: <1484573225-19095-1-git-send-email-clg@kaod.org> <1484573225-19095-2-git-send-email-clg@kaod.org> <20170124151353.5bbffae0@bbrezillon> <7bdf47c3-d3b7-92a2-47c1-99e4bd6b4f44@kaod.org> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <7bdf47c3-d3b7-92a2-47c1-99e4bd6b4f44@kaod.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-mtd" Errors-To: linux-mtd-bounces+gldm-linux-mtd-36=gmane.org@lists.infradead.org To: =?UTF-8?B?Q8OpZHJpYw==?= Le Goater Cc: Mark Rutland , devicetree@vger.kernel.org, Richard Weinberger , Marek Vasut , Rob Herring , linux-mtd@lists.infradead.org, Cyrille Pitchen , Brian Norris , David Woodhouse List-Id: devicetree@vger.kernel.org T24gV2VkLCAyNSBKYW4gMjAxNyAxNzo0NzoxMyArMDEwMApDw6lkcmljIExlIEdvYXRlciA8Y2xn QGthb2Qub3JnPiB3cm90ZToKCj4gT24gMDEvMjQvMjAxNyAwMzoxMyBQTSwgQm9yaXMgQnJlemls bG9uIHdyb3RlOgo+ID4gSGkgQ8OpZHJpYywKPiA+IAo+ID4gT24gTW9uLCAxNiBKYW4gMjAxNyAx NDoyNzowMyArMDEwMAo+ID4gQ8OpZHJpYyBMZSBHb2F0ZXIgPGNsZ0BrYW9kLm9yZz4gd3JvdGU6 Cj4gPiAgIAo+ID4+IFRoaXMgY2FuIGJlIHVzZWQgdG8gZWFzaWx5IGlkZW50aWZ5IGEgc3BlY2lm aWMgY2hpcCBvbiBhIHN5c3RlbSB3aXRoCj4gPj4gbXVsdGlwbGUgY2hpcHMuCj4gPj4KPiA+PiBT dWdnZXN0ZWQtYnk6IEJvcmlzIEJyZXppbGxvbiA8Ym9yaXMuYnJlemlsbG9uQGZyZWUtZWxlY3Ry b25zLmNvbT4KPiA+PiBTaWduZWQtb2ZmLWJ5OiBDw6lkcmljIExlIEdvYXRlciA8Y2xnQGthb2Qu b3JnPgo+ID4+IC0tLQo+ID4+ICBkcml2ZXJzL210ZC9tdGRjb3JlLmMgfCA3ICsrKysrKysKPiA+ PiAgMSBmaWxlIGNoYW5nZWQsIDcgaW5zZXJ0aW9ucygrKQo+ID4+Cj4gPj4gZGlmZiAtLWdpdCBh L2RyaXZlcnMvbXRkL210ZGNvcmUuYyBiL2RyaXZlcnMvbXRkL210ZGNvcmUuYwo+ID4+IGluZGV4 IDA1Mjc3MmY3Y2FlZi4uYmY2MTU1N2I1OTlkIDEwMDY0NAo+ID4+IC0tLSBhL2RyaXZlcnMvbXRk L210ZGNvcmUuYwo+ID4+ICsrKyBiL2RyaXZlcnMvbXRkL210ZGNvcmUuYwo+ID4+IEBAIC02NTQs NiArNjU0LDEzIEBAIHN0YXRpYyBpbnQgbXRkX2FkZF9kZXZpY2VfcGFydGl0aW9ucyhzdHJ1Y3Qg bXRkX2luZm8gKm10ZCwKPiA+PiAgICovCj4gPj4gIHN0YXRpYyB2b2lkIG10ZF9zZXRfZGV2X2Rl ZmF1bHRzKHN0cnVjdCBtdGRfaW5mbyAqbXRkKQo+ID4+ICB7Cj4gPj4gKwkvKgo+ID4+ICsJICog SWYgRFQgc3VwcG9ydCBpcyBlbmFibGVkIGFuZCB3ZSBoYXZlIGEgdmFsaWQgb2Zfbm9kZSBwb2lu dGVyLCB0cnkgdG8KPiA+PiArCSAqIGV4dHJhY3QgdGhlIE1URCBuYW1lIGZyb20gdGhlIGxhYmVs IHByb3BlcnR5Lgo+ID4+ICsJICovCj4gPj4gKwlpZiAoSVNfRU5BQkxFRChDT05GSUdfT0YpICYm IG10ZC0+ZGV2Lm9mX25vZGUpCj4gPj4gKwkJb2ZfcHJvcGVydHlfcmVhZF9zdHJpbmcobXRkLT5k ZXYub2Zfbm9kZSwgImxhYmVsIiwgJm10ZC0+bmFtZSk7Cj4gPj4gKyAgCj4gPiAKPiA+IEkgcmVh bGl6ZSB0aGlzIGtpbmQgb2YgdGhpbmcgd291bGQgYmUgYmV0dGVyIHBsYWNlZCBpbiBtdGRfc2V0 X29mX25vZGUoKQo+ID4gKHNlZSB0aGUgcGF0Y2ggYmVsb3cpLiBNb2RpZnlpbmcgdGhlIG10ZC0+ bmFtZSBwb2ludGVyIGluIHRoZSBiYWNrIG9mCj4gPiBNVEQgZHJpdmVycyBpcyBub3Qgc3VjaCBh IGdvb2QgaWRlYSAoc3VwcG9zZSB0aGUgZHJpdmVyIGFsbG9jYXRlZCB0aGUKPiA+IG1lbW9yeSB3 aXRoIGEgcmVndWxhciBrbWFsbG9jKCkgYW5kIHRyaWVzIHRvIGZyZWUgbXRkLT5uYW1lIGluIHRo ZSByZW1vdmUKPiA+IHBhdGgpLgo+ID4gCj4gPiBJZiB3ZSBtb3ZlIHRoYXQgdG8gbXRkX3NldF9v Zl9ub2RlKCksIGRyaXZlcnMgdGhhdCB3YW50cyB0byBzdXBwb3J0IHRoaXMKPiA+IGxhYmVsIHBy b3BlcnR5IGp1c3QgaGF2ZSB0byBjaGVjayBpZiBtdGQtPm5hbWUgaXMgTlVMTCAoYWZ0ZXIgY2Fs bGluZwo+ID4gbXRkX3NldF9vZl9ub2RlKCkgb3IgbmFuZF9zZXRfZmxhc2hfbm9kZSgpKSBiZWZv cmUgYXNzaWduaW5nIGEgZGVmYXVsdAo+ID4gbmFtZS4KPiA+IEZvciB1bm1vZGlmaWVkIGRyaXZl cnMgd2Uga2VlcCB0aGUgZXhpc3RpbmcgYmVoYXZpb3I6IHRoZXknbGwganVzdAo+ID4gdW5jb25k aXRpb25hbGx5IG92ZXJyaWRlIG10ZC0+bmFtZSB3aXRoIHRoZWlyIG93biB2YWx1ZSAod2hpY2gg bWlnaHQgb3IKPiA+IG1pZ2h0IG5vdCBiZSBkeW5hbWljYWxseSBhbGxvY2F0ZWQpLiAgCj4gCj4g b2suIFNvIHRoZSBleHBlY3RlZCBiZWhhdmlvciBsb29rcyBjb3JyZWN0IHRvIG1lLCBidXQgYWRk aW5nIGEgY2FsbCB0byAKPiBvZl9wcm9wZXJ0eV9yZWFkX3N0cmluZygpIGluIHRoZSBpbmxpbmUg YmVsb3cgZmVlbHMgYSBsaXR0bGUgaGFja3kuIAo+IERvZXNuJ3QgaXQgPyAKPiAKPiBNYXkgYmUg d2UgbmVlZCBhbiBleHRyYSBjaGVjayBvbiBJU19FTkFCTEVEKENPTkZJR19PRikgYWxzbyA/IAoK VGhpcyBpcyBhbGwgc2FmZSwgYmVjYXVzZSB0aGUgb2YuaCBoZWFkZXIgZGVmaW5lcyBzdHVicyBp ZiBDT05GSUdfT0YgaXMKbm90IHNldC4gVGhhdCBqdXN0IG1lYW5zIHRoZSBuYW1lIHdpbGwgYmUg dW5jaGFuZ2VkLCBidXQgeW91IHNob3VsZG4ndApoYXZlIGFueSBwcm9ibGVtIChuZWl0aGVyIGFz IGNvbXBpbGF0aW9uIHRpbWUgbm9yIGF0IHJ1bnRpbWUpLgoKX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fCkxpbnV4IE1URCBkaXNjdXNzaW9uIG1h aWxpbmcgbGlzdApodHRwOi8vbGlzdHMuaW5mcmFkZWFkLm9yZy9tYWlsbWFuL2xpc3RpbmZvL2xp bnV4LW10ZC8K