rtc: ds1307: use generic nvmem

Instead of adding a binary sysfs attribute from the driver (which suffers
from a race condition as the attribute appears after the device), use the
core to register an nvmem device.

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

diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c
index 6f94f20326fb9a3336f3e09e33607d3f4d73c15c..76652566cc31f498787b1dd7281b097ff64595b4 100644 (file)
--- a/drivers/rtc/rtc-ds1307.c
+++ b/drivers/rtc/rtc-ds1307.c
@@ -118,7 +118,7 @@ struct ds1307 {
        u8                      offset; /* register's offset */
        u8                      regs[11];
        u16                     nvram_offset;
-       struct bin_attribute    *nvram;
+       struct nvmem_config     nvmem_cfg;
        enum ds_type            type;
        unsigned long           flags;
 #define HAS_NVRAM      0               /* bit 0 == sysfs file active */
@@ -895,43 +895,24 @@ static const struct rtc_class_ops mcp794xx_rtc_ops = {
 
 /*----------------------------------------------------------------------*/
 
-static ssize_t
-ds1307_nvram_read(struct file *filp, struct kobject *kobj,
-               struct bin_attribute *attr,
-               char *buf, loff_t off, size_t count)
+static int ds1307_nvram_read(void *priv, unsigned int offset, void *val,
+                            size_t bytes)
 {
-       struct ds1307           *ds1307;
-       int                     result;
-
-       ds1307 = dev_get_drvdata(kobj_to_dev(kobj));
+       struct ds1307 *ds1307 = priv;
 
-       result = regmap_bulk_read(ds1307->regmap, ds1307->nvram_offset + off,
-                                 buf, count);
-       if (result)
-               dev_err(ds1307->dev, "%s error %d\n", "nvram read", result);
-       return result;
+       return regmap_bulk_read(ds1307->regmap, ds1307->nvram_offset + offset,
+                               val, bytes);
 }
 
-static ssize_t
-ds1307_nvram_write(struct file *filp, struct kobject *kobj,
-               struct bin_attribute *attr,
-               char *buf, loff_t off, size_t count)
+static int ds1307_nvram_write(void *priv, unsigned int offset, void *val,
+                             size_t bytes)
 {
-       struct ds1307           *ds1307;
-       int                     result;
+       struct ds1307 *ds1307 = priv;
 
-       ds1307 = dev_get_drvdata(kobj_to_dev(kobj));
-
-       result = regmap_bulk_write(ds1307->regmap, ds1307->nvram_offset + off,
-                                  buf, count);
-       if (result) {
-               dev_err(ds1307->dev, "%s error %d\n", "nvram write", result);
-               return result;
-       }
-       return count;
+       return regmap_bulk_write(ds1307->regmap, ds1307->nvram_offset + offset,
+                                val, bytes);
 }
 
-
 /*----------------------------------------------------------------------*/
 
 static u8 do_trickle_setup_ds1339(struct ds1307 *ds1307,
@@ -1704,37 +1685,17 @@ read_rtc:
        }
 
        if (chip->nvram_size) {
-
-               ds1307->nvram = devm_kzalloc(ds1307->dev,
-                                       sizeof(struct bin_attribute),
-                                       GFP_KERNEL);
-               if (!ds1307->nvram) {
-                       dev_err(ds1307->dev,
-                               "cannot allocate memory for nvram sysfs\n");
-               } else {
-
-                       ds1307->nvram->attr.name = "nvram";
-                       ds1307->nvram->attr.mode = S_IRUGO | S_IWUSR;
-
-                       sysfs_bin_attr_init(ds1307->nvram);
-
-                       ds1307->nvram->read = ds1307_nvram_read;
-                       ds1307->nvram->write = ds1307_nvram_write;
-                       ds1307->nvram->size = chip->nvram_size;
-                       ds1307->nvram_offset = chip->nvram_offset;
-
-                       err = sysfs_create_bin_file(&ds1307->dev->kobj,
-                                                   ds1307->nvram);
-                       if (err) {
-                               dev_err(ds1307->dev,
-                                       "unable to create sysfs file: %s\n",
-                                       ds1307->nvram->attr.name);
-                       } else {
-                               set_bit(HAS_NVRAM, &ds1307->flags);
-                               dev_info(ds1307->dev, "%zu bytes nvram\n",
-                                        ds1307->nvram->size);
-                       }
-               }
+               ds1307->nvmem_cfg.name = "ds1307_nvram";
+               ds1307->nvmem_cfg.word_size = 1;
+               ds1307->nvmem_cfg.stride = 1;
+               ds1307->nvmem_cfg.size = chip->nvram_size;
+               ds1307->nvmem_cfg.reg_read = ds1307_nvram_read;
+               ds1307->nvmem_cfg.reg_write = ds1307_nvram_write;
+               ds1307->nvmem_cfg.priv = ds1307;
+               ds1307->nvram_offset = chip->nvram_offset;
+
+               ds1307->rtc->nvmem_config = &ds1307->nvmem_cfg;
+               ds1307->rtc->nvram_old_abi = true;
        }
 
        ds1307->rtc->ops = rtc_ops;
@@ -1753,11 +1714,6 @@ exit:
 
 static int ds1307_remove(struct i2c_client *client)
 {
-       struct ds1307 *ds1307 = i2c_get_clientdata(client);
-
-       if (test_and_clear_bit(HAS_NVRAM, &ds1307->flags))
-               sysfs_remove_bin_file(&ds1307->dev->kobj, ds1307->nvram);
-
        return 0;
 }