[PATCH 3/3] rtc: ds1511: use generic nvmem

From: Alexandre Belloni
Date: Thu Oct 12 2017 - 18:05:41 EST


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@xxxxxxxxxxxxxxxxxx>
---
drivers/rtc/rtc-ds1511.c | 58 ++++++++++++++++++------------------------------
1 file changed, 22 insertions(+), 36 deletions(-)

diff --git a/drivers/rtc/rtc-ds1511.c b/drivers/rtc/rtc-ds1511.c
index eda45358d63a..1e95312a6f2e 100644
--- a/drivers/rtc/rtc-ds1511.c
+++ b/drivers/rtc/rtc-ds1511.c
@@ -398,42 +398,37 @@ static const struct rtc_class_ops ds1511_rtc_ops = {
.alarm_irq_enable = ds1511_rtc_alarm_irq_enable,
};

-static ssize_t
-ds1511_nvram_read(struct file *filp, struct kobject *kobj,
- struct bin_attribute *ba,
- char *buf, loff_t pos, size_t size)
+static int ds1511_nvram_read(void *priv, unsigned int pos, void *buf,
+ size_t size)
{
- ssize_t count;
+ int i;

rtc_write(pos, DS1511_RAMADDR_LSB);
- for (count = 0; count < size; count++)
- *buf++ = rtc_read(DS1511_RAMDATA);
+ for (i = 0; i < size; i++)
+ *(char *)buf++ = rtc_read(DS1511_RAMDATA);

- return count;
+ return 0;
}

-static ssize_t
-ds1511_nvram_write(struct file *filp, struct kobject *kobj,
- struct bin_attribute *bin_attr,
- char *buf, loff_t pos, size_t size)
+static int ds1511_nvram_write(void *priv, unsigned int pos, void *buf,
+ size_t size)
{
- ssize_t count;
+ int i;

rtc_write(pos, DS1511_RAMADDR_LSB);
- for (count = 0; count < size; count++)
- rtc_write(*buf++, DS1511_RAMDATA);
+ for (i = 0; i < size; i++)
+ rtc_write(*(char *)buf++, DS1511_RAMDATA);

- return count;
+ return 0;
}

-static struct bin_attribute ds1511_nvram_attr = {
- .attr = {
- .name = "nvram",
- .mode = S_IRUGO | S_IWUSR,
- },
+static struct nvmem_config ds1511_nvmem_cfg = {
+ .name = "ds1511_nvram",
+ .word_size = 1,
+ .stride = 1,
.size = DS1511_RAM_MAX,
- .read = ds1511_nvram_read,
- .write = ds1511_nvram_write,
+ .reg_read = ds1511_nvram_read,
+ .reg_write = ds1511_nvram_write,
};

static int ds1511_rtc_probe(struct platform_device *pdev)
@@ -483,6 +478,10 @@ static int ds1511_rtc_probe(struct platform_device *pdev)

pdata->rtc->ops = &ds1511_rtc_ops;

+ ds1511_nvmem_cfg.priv = &pdev->dev;
+ pdata->rtc->nvmem_config = &ds1511_nvmem_cfg;
+ pdata->rtc->nvram_old_abi = true;
+
ret = rtc_register_device(pdata->rtc);
if (ret)
return ret;
@@ -501,18 +500,6 @@ static int ds1511_rtc_probe(struct platform_device *pdev)
}
}

- ret = sysfs_create_bin_file(&pdev->dev.kobj, &ds1511_nvram_attr);
- if (ret)
- dev_err(&pdev->dev, "Unable to create sysfs entry: %s\n",
- ds1511_nvram_attr.attr.name);
-
- return 0;
-}
-
-static int ds1511_rtc_remove(struct platform_device *pdev)
-{
- sysfs_remove_bin_file(&pdev->dev.kobj, &ds1511_nvram_attr);
-
return 0;
}

@@ -521,7 +508,6 @@ MODULE_ALIAS("platform:ds1511");

static struct platform_driver ds1511_rtc_driver = {
.probe = ds1511_rtc_probe,
- .remove = ds1511_rtc_remove,
.driver = {
.name = "ds1511",
},
--
2.14.2