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rtc: cmos: use generic nvmem

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Instead of adding a binary sysfs attribute from the driver, use the
core to register an nvmem device. This allows to use the in-kernel
interface to access the nvram.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
This commit is contained in:
Alexandre Belloni 2018-02-12 23:47:46 +01:00
parent 53d29e0a3a
commit 8b5b7958fd
1 changed files with 30 additions and 43 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

73
drivers/rtc/rtc-cmos.c
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@ -541,11 +541,10 @@ static const struct rtc_class_ops cmos_rtc_ops = {
#define NVRAM_OFFSET (RTC_REG_D + 1)
static ssize_t
cmos_nvram_read(struct file *filp, struct kobject *kobj,
struct bin_attribute *attr,
char *buf, loff_t off, size_t count)
static int cmos_nvram_read(void *priv, unsigned int off, void *val,
size_t count)
{
unsigned char *buf = val;
int retval;
off += NVRAM_OFFSET;
@ -563,16 +562,13 @@ cmos_nvram_read(struct file *filp, struct kobject *kobj,
return retval;
}
static ssize_t
cmos_nvram_write(struct file *filp, struct kobject *kobj,
struct bin_attribute *attr,
char *buf, loff_t off, size_t count)
static int cmos_nvram_write(void *priv, unsigned int off, void *val,
size_t count)
{
struct cmos_rtc *cmos;
struct cmos_rtc *cmos = priv;
unsigned char *buf = val;
int retval;
cmos = dev_get_drvdata(container_of(kobj, struct device, kobj));
/* NOTE: on at least PCs and Ataris, the boot firmware uses a
* checksum on part of the NVRAM data. That's currently ignored
* here. If userspace is smart enough to know what fields of
@ -598,17 +594,6 @@ cmos_nvram_write(struct file *filp, struct kobject *kobj,
return retval;
}
static struct bin_attribute nvram = {
.attr = {
.name = "nvram",
.mode = S_IRUGO | S_IWUSR,
},
.read = cmos_nvram_read,
.write = cmos_nvram_write,
/* size gets set up later */
};
/*----------------------------------------------------------------*/
static struct cmos_rtc cmos_rtc;
@ -675,6 +660,14 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
unsigned char rtc_control;
unsigned address_space;
u32 flags = 0;
struct nvmem_config nvmem_cfg = {
.name = "cmos_nvram",
.word_size = 1,
.stride = 1,
.reg_read = cmos_nvram_read,
.reg_write = cmos_nvram_write,
.priv = &cmos_rtc,
};
/* there can be only one ... */
if (cmos_rtc.dev)
@ -813,32 +806,28 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
}
}
/* export at least the first block of NVRAM */
nvram.size = address_space - NVRAM_OFFSET;
retval = sysfs_create_bin_file(&dev->kobj, &nvram);
if (retval < 0) {
dev_dbg(dev, "can't create nvram file? %d\n", retval);
goto cleanup2;
}
cmos_rtc.rtc->ops = &cmos_rtc_ops;
cmos_rtc.rtc->nvram_old_abi = true;
retval = rtc_register_device(cmos_rtc.rtc);
if (retval)
goto cleanup3;
goto cleanup2;
dev_info(dev, "%s%s, %zd bytes nvram%s\n",
!is_valid_irq(rtc_irq) ? "no alarms" :
cmos_rtc.mon_alrm ? "alarms up to one year" :
cmos_rtc.day_alrm ? "alarms up to one month" :
"alarms up to one day",
cmos_rtc.century ? ", y3k" : "",
nvram.size,
is_hpet_enabled() ? ", hpet irqs" : "");
/* export at least the first block of NVRAM */
nvmem_cfg.size = address_space - NVRAM_OFFSET;
if (rtc_nvmem_register(cmos_rtc.rtc, &nvmem_cfg))
dev_err(dev, "nvmem registration failed\n");
dev_info(dev, "%s%s, %d bytes nvram%s\n",
!is_valid_irq(rtc_irq) ? "no alarms" :
cmos_rtc.mon_alrm ? "alarms up to one year" :
cmos_rtc.day_alrm ? "alarms up to one month" :
"alarms up to one day",
cmos_rtc.century ? ", y3k" : "",
nvmem_cfg.size,
is_hpet_enabled() ? ", hpet irqs" : "");
return 0;
cleanup3:
sysfs_remove_bin_file(&dev->kobj, &nvram);
cleanup2:
if (is_valid_irq(rtc_irq))
free_irq(rtc_irq, cmos_rtc.rtc);
@ -867,8 +856,6 @@ static void cmos_do_remove(struct device *dev)
cmos_do_shutdown(cmos->irq);
sysfs_remove_bin_file(&dev->kobj, &nvram);
if (is_valid_irq(cmos->irq)) {
free_irq(cmos->irq, cmos->rtc);
hpet_unregister_irq_handler(cmos_interrupt);