rtc: nvmem: remove nvmem from struct rtc_device

Using devm_nvmem_register allows to avoid tracking the nvmem pointer in the
rtc_device structure.
This ultimately allows to register multiple nvmem devices from an RTC
driver.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

2 files changed, 10 insertions, 15 deletions

diff --git a/drivers/rtc/nvmem.c b/drivers/rtc/nvmem.c
index 2a7220d8b02d..ebdfe8e3a1a0 100644
--- a/drivers/rtc/nvmem.c
+++ b/drivers/rtc/nvmem.c
@@ -25,11 +25,9 @@ rtc_nvram_read(struct file *filp, struct kobject *kobj,
                struct bin_attribute *attr,
                char *buf, loff_t off, size_t count)
 {
-        struct rtc_device *rtc = attr->private;
-
         dev_warn_once(kobj_to_dev(kobj), nvram_warning);
 
-        return nvmem_device_read(rtc->nvmem, off, count, buf);
+        return nvmem_device_read(attr->private, off, count, buf);
 }
 
 static ssize_t
@@ -37,14 +35,13 @@ rtc_nvram_write(struct file *filp, struct kobject *kobj,
                 struct bin_attribute *attr,
                 char *buf, loff_t off, size_t count)
 {
-        struct rtc_device *rtc = attr->private;
-
         dev_warn_once(kobj_to_dev(kobj), nvram_warning);
 
-        return nvmem_device_write(rtc->nvmem, off, count, buf);
+        return nvmem_device_write(attr->private, off, count, buf);
 }
 
-static int rtc_nvram_register(struct rtc_device *rtc, size_t size)
+static int rtc_nvram_register(struct rtc_device *rtc,
+                              struct nvmem_device *nvmem, size_t size)
 {
         int err;
 
@@ -56,7 +53,7 @@ static int rtc_nvram_register(struct rtc_device *rtc, size_t size)
 
         rtc->nvram->attr.name = "nvram";
         rtc->nvram->attr.mode = 0644;
-        rtc->nvram->private = rtc;
+        rtc->nvram->private = nvmem;
 
         sysfs_bin_attr_init(rtc->nvram);
 
@@ -85,21 +82,20 @@ 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;
+        struct nvmem_device *nvmem;
 
         if (!nvmem_config)
                 return -ENODEV;
 
         nvmem_config->dev = rtc->dev.parent;
         nvmem_config->owner = rtc->owner;
-        rtc->nvmem = devm_nvmem_register(rtc->dev.parent, nvmem_config);
-        if (IS_ERR(rtc->nvmem))
-                return PTR_ERR(rtc->nvmem);
+        nvmem = devm_nvmem_register(rtc->dev.parent, nvmem_config);
+        if (IS_ERR(nvmem))
+                return PTR_ERR(nvmem);
 
         /* Register the old ABI */
         if (rtc->nvram_old_abi)
-                rtc_nvram_register(rtc, nvmem_config->size);
+                rtc_nvram_register(rtc, nvmem, nvmem_config->size);
 
         return 0;
 }
diff --git a/include/linux/rtc.h b/include/linux/rtc.h
index 311375dbb673..58147b057acd 100644
--- a/include/linux/rtc.h
+++ b/include/linux/rtc.h
@@ -138,7 +138,6 @@ struct rtc_device {
 
         bool registered;
 
-        struct nvmem_device *nvmem;
         /* Old ABI support */
         bool nvram_old_abi;
         struct bin_attribute *nvram;