rtc: m48t86: 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>
This commit is contained in:
Alexandre Belloni 2017-10-13 00:04:21 +02:00
parent 5508c72528
commit f8033aabb2

View File

@ -163,35 +163,30 @@ static const struct rtc_class_ops m48t86_rtc_ops = {
.proc = m48t86_rtc_proc,
};
static ssize_t m48t86_nvram_read(struct file *filp, struct kobject *kobj,
struct bin_attribute *attr,
char *buf, loff_t off, size_t count)
static int m48t86_nvram_read(void *priv, unsigned int off, void *buf,
size_t count)
{
struct device *dev = kobj_to_dev(kobj);
struct device *dev = priv;
unsigned int i;
for (i = 0; i < count; i++)
buf[i] = m48t86_readb(dev, M48T86_NVRAM(off + i));
((u8 *)buf)[i] = m48t86_readb(dev, M48T86_NVRAM(off + i));
return count;
return 0;
}
static ssize_t m48t86_nvram_write(struct file *filp, struct kobject *kobj,
struct bin_attribute *attr,
char *buf, loff_t off, size_t count)
static int m48t86_nvram_write(void *priv, unsigned int off, void *buf,
size_t count)
{
struct device *dev = kobj_to_dev(kobj);
struct device *dev = priv;
unsigned int i;
for (i = 0; i < count; i++)
m48t86_writeb(dev, buf[i], M48T86_NVRAM(off + i));
m48t86_writeb(dev, ((u8 *)buf)[i], M48T86_NVRAM(off + i));
return count;
return 0;
}
static BIN_ATTR(nvram, 0644, m48t86_nvram_read, m48t86_nvram_write,
M48T86_NVRAM_LEN);
/*
* The RTC is an optional feature at purchase time on some Technologic Systems
* boards. Verify that it actually exists by checking if the last two bytes
@ -223,6 +218,15 @@ static bool m48t86_verify_chip(struct platform_device *pdev)
return false;
}
static struct nvmem_config m48t86_nvmem_cfg = {
.name = "m48t86_nvram",
.word_size = 1,
.stride = 1,
.size = M48T86_NVRAM_LEN,
.reg_read = m48t86_nvram_read,
.reg_write = m48t86_nvram_write,
};
static int m48t86_rtc_probe(struct platform_device *pdev)
{
struct m48t86_rtc_info *info;
@ -261,6 +265,10 @@ static int m48t86_rtc_probe(struct platform_device *pdev)
info->rtc->ops = &m48t86_rtc_ops;
m48t86_nvmem_cfg.priv = &pdev->dev;
info->rtc->nvmem_config = &m48t86_nvmem_cfg;
info->rtc->nvram_old_abi = true;
err = rtc_register_device(info->rtc);
if (err)
return err;
@ -270,15 +278,6 @@ static int m48t86_rtc_probe(struct platform_device *pdev)
dev_info(&pdev->dev, "battery %s\n",
(reg & M48T86_D_VRT) ? "ok" : "exhausted");
if (device_create_bin_file(&pdev->dev, &bin_attr_nvram))
dev_err(&pdev->dev, "failed to create nvram sysfs entry\n");
return 0;
}
static int m48t86_rtc_remove(struct platform_device *pdev)
{
device_remove_bin_file(&pdev->dev, &bin_attr_nvram);
return 0;
}
@ -287,7 +286,6 @@ static struct platform_driver m48t86_rtc_platform_driver = {
.name = "rtc-m48t86",
},
.probe = m48t86_rtc_probe,
.remove = m48t86_rtc_remove,
};
module_platform_driver(m48t86_rtc_platform_driver);