mtd: core: provide unique name for nvmem device

[ Upstream commit c048b60d39 ]

If there is more than one mtd device which supports OTP, there will
be a kernel warning about duplicated sysfs entries and the probing will
fail. This is because the nvmem device name is not unique. Make it
unique by prepending the name of the mtd. E.g. before the name was
"user-otp", now it will be "mtd0-user-otp".

For reference the kernel splash is:
[    4.665531] sysfs: cannot create duplicate filename '/bus/nvmem/devices/user-otp'
[    4.673056] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.15.0-next-20211101+ #1296
[    4.680565] Hardware name: Kontron SMARC-sAL28 (Single PHY) on SMARC Eval 2.0 carrier (DT)
[    4.688856] Call trace:
[    4.691303]  dump_backtrace+0x0/0x1bc
[    4.694984]  show_stack+0x24/0x30
[    4.698306]  dump_stack_lvl+0x68/0x84
[    4.701980]  dump_stack+0x18/0x34
[    4.705302]  sysfs_warn_dup+0x70/0x90
[    4.708973]  sysfs_do_create_link_sd+0x144/0x150
[    4.713603]  sysfs_create_link+0x2c/0x50
[    4.717535]  bus_add_device+0x74/0x120
[    4.721293]  device_add+0x330/0x890
[    4.724791]  device_register+0x2c/0x40
[    4.728550]  nvmem_register+0x240/0x9f0
[    4.732398]  mtd_otp_nvmem_register+0xb0/0x10c
[    4.736854]  mtd_device_parse_register+0x28c/0x2b4
[    4.741659]  spi_nor_probe+0x20c/0x2e0
[    4.745418]  spi_mem_probe+0x78/0xbc
[    4.749001]  spi_probe+0x90/0xf0
[    4.752237]  really_probe.part.0+0xa4/0x320
..
[    4.873936] mtd mtd1: Failed to register OTP NVMEM device
[    4.894468] spi-nor: probe of spi0.0 failed with error -17

Fixes: 4b361cfa86 ("mtd: core: add OTP nvmem provider support")
Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20211104134843.2642800-1-michael@walle.cc
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Michael Walle 2021-11-04 14:48:43 +01:00 committed by Greg Kroah-Hartman
parent aee7ef0305
commit 31d60f5282

View file

@ -825,8 +825,7 @@ static struct nvmem_device *mtd_otp_nvmem_register(struct mtd_info *mtd,
/* OTP nvmem will be registered on the physical device */
config.dev = mtd->dev.parent;
/* just reuse the compatible as name */
config.name = compatible;
config.name = kasprintf(GFP_KERNEL, "%s-%s", dev_name(&mtd->dev), compatible);
config.id = NVMEM_DEVID_NONE;
config.owner = THIS_MODULE;
config.type = NVMEM_TYPE_OTP;
@ -842,6 +841,7 @@ static struct nvmem_device *mtd_otp_nvmem_register(struct mtd_info *mtd,
nvmem = NULL;
of_node_put(np);
kfree(config.name);
return nvmem;
}