From ab3ea36eda76069ba52e9b6aef5a9370b0b462bf Mon Sep 17 00:00:00 2001 From: Alexandre Belloni Date: Mon, 12 Feb 2018 23:47:18 +0100 Subject: [PATCH] rtc: nvmem: disallow registering nvmem more than once Make rtc_nvmem_register return -EBUSY when an nvmem is already registered for that RTC. Signed-off-by: Alexandre Belloni --- drivers/rtc/nvmem.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/rtc/nvmem.c b/drivers/rtc/nvmem.c index 293df6db7c42..fd1c39a5ade5 100644 --- a/drivers/rtc/nvmem.c +++ b/drivers/rtc/nvmem.c @@ -87,6 +87,9 @@ static void rtc_nvram_unregister(struct rtc_device *rtc) int rtc_nvmem_register(struct rtc_device *rtc, struct nvmem_config *nvmem_config) { + if (!IS_ERR_OR_NULL(rtc->nvmem)) + return -EBUSY; + if (!nvmem_config) return -ENODEV;