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rtc: ds1685: remove sysfs access to control registers 

Access to the control registers is mostly not needed and can cause runtime
issues (like missed interrupts). Remove this debugging interface.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
This commit is contained in:
Alexandre Belloni 2018-06-18 10:52:02 +02:00
parent 30a5271d45
commit a41efe03e6
2 changed files with 0 additions and 381 deletions
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12
drivers/rtc/Kconfig
View File

@ -1027,18 +1027,6 @@ config RTC_DS1685_PROC_REGS
Unless you are debugging this driver, choose N.
config RTC_DS1685_SYSFS_REGS
bool "SysFS access to RTC register bits"
depends on RTC_DRV_DS1685_FAMILY && SYSFS
help
Enable this to provide access to the RTC control register bits
in /sys. Some of the bits are read-write, others are read-only.
Keep in mind that reading Control C's bits automatically clears
all pending IRQ flags - this can cause lost interrupts.
If you know that you need access to these bits, choose Y, Else N.
config RTC_DRV_DS1742
tristate "Maxim/Dallas DS1742/1743"
depends on HAS_IOMEM

369
drivers/rtc/rtc-ds1685.c
View File

@ -1188,341 +1188,6 @@ ds1685_rtc_sysfs_misc_grp = {
.attrs = ds1685_rtc_sysfs_misc_attrs,
};
#ifdef CONFIG_RTC_DS1685_SYSFS_REGS
/**
* struct ds1685_rtc_ctrl_regs.
* @name: char pointer for the bit name.
* @reg: control register the bit is in.
* @bit: the bit's offset in the register.
*/
struct ds1685_rtc_ctrl_regs {
const char *name;
const u8 reg;
const u8 bit;
};
/*
* Ctrl register bit lookup table.
*/
static const struct ds1685_rtc_ctrl_regs
ds1685_ctrl_regs_table[] = {
{ "uip", RTC_CTRL_A, RTC_CTRL_A_UIP },
{ "dv2", RTC_CTRL_A, RTC_CTRL_A_DV2 },
{ "dv1", RTC_CTRL_A, RTC_CTRL_A_DV1 },
{ "dv0", RTC_CTRL_A, RTC_CTRL_A_DV0 },
{ "rs3", RTC_CTRL_A, RTC_CTRL_A_RS3 },
{ "rs2", RTC_CTRL_A, RTC_CTRL_A_RS2 },
{ "rs1", RTC_CTRL_A, RTC_CTRL_A_RS1 },
{ "rs0", RTC_CTRL_A, RTC_CTRL_A_RS0 },
{ "set", RTC_CTRL_B, RTC_CTRL_B_SET },
{ "pie", RTC_CTRL_B, RTC_CTRL_B_PIE },
{ "aie", RTC_CTRL_B, RTC_CTRL_B_AIE },
{ "uie", RTC_CTRL_B, RTC_CTRL_B_UIE },
{ "sqwe", RTC_CTRL_B, RTC_CTRL_B_SQWE },
{ "dm", RTC_CTRL_B, RTC_CTRL_B_DM },
{ "2412", RTC_CTRL_B, RTC_CTRL_B_2412 },
{ "dse", RTC_CTRL_B, RTC_CTRL_B_DSE },
{ "irqf", RTC_CTRL_C, RTC_CTRL_C_IRQF },
{ "pf", RTC_CTRL_C, RTC_CTRL_C_PF },
{ "af", RTC_CTRL_C, RTC_CTRL_C_AF },
{ "uf", RTC_CTRL_C, RTC_CTRL_C_UF },
{ "vrt", RTC_CTRL_D, RTC_CTRL_D_VRT },
{ "vrt2", RTC_EXT_CTRL_4A, RTC_CTRL_4A_VRT2 },
{ "incr", RTC_EXT_CTRL_4A, RTC_CTRL_4A_INCR },
{ "pab", RTC_EXT_CTRL_4A, RTC_CTRL_4A_PAB },
{ "rf", RTC_EXT_CTRL_4A, RTC_CTRL_4A_RF },
{ "wf", RTC_EXT_CTRL_4A, RTC_CTRL_4A_WF },
{ "kf", RTC_EXT_CTRL_4A, RTC_CTRL_4A_KF },
#if !defined(CONFIG_RTC_DRV_DS1685) && !defined(CONFIG_RTC_DRV_DS1689)
{ "bme", RTC_EXT_CTRL_4A, RTC_CTRL_4A_BME },
#endif
{ "abe", RTC_EXT_CTRL_4B, RTC_CTRL_4B_ABE },
{ "e32k", RTC_EXT_CTRL_4B, RTC_CTRL_4B_E32K },
{ "cs", RTC_EXT_CTRL_4B, RTC_CTRL_4B_CS },
{ "rce", RTC_EXT_CTRL_4B, RTC_CTRL_4B_RCE },
{ "prs", RTC_EXT_CTRL_4B, RTC_CTRL_4B_PRS },
{ "rie", RTC_EXT_CTRL_4B, RTC_CTRL_4B_RIE },
{ "wie", RTC_EXT_CTRL_4B, RTC_CTRL_4B_WIE },
{ "kse", RTC_EXT_CTRL_4B, RTC_CTRL_4B_KSE },
{ NULL, 0, 0 },
};
/**
* ds1685_rtc_sysfs_ctrl_regs_lookup - ctrl register bit lookup function.
* @name: ctrl register bit to look up in ds1685_ctrl_regs_table.
*/
static const struct ds1685_rtc_ctrl_regs*
ds1685_rtc_sysfs_ctrl_regs_lookup(const char *name)
{
const struct ds1685_rtc_ctrl_regs *p = ds1685_ctrl_regs_table;
for (; p->name != NULL; ++p)
if (strcmp(p->name, name) == 0)
return p;
return NULL;
}
/**
* ds1685_rtc_sysfs_ctrl_regs_show - reads a ctrl register bit via sysfs.
* @dev: pointer to device structure.
* @attr: pointer to device_attribute structure.
* @buf: pointer to char array to hold the output.
*/
static ssize_t
ds1685_rtc_sysfs_ctrl_regs_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
u8 tmp;
struct ds1685_priv *rtc = dev_get_drvdata(dev);
const struct ds1685_rtc_ctrl_regs *reg_info =
ds1685_rtc_sysfs_ctrl_regs_lookup(attr->attr.name);
/* Make sure we actually matched something. */
if (!reg_info)
return -EINVAL;
/* No spinlock during a read -- mutex is already held. */
ds1685_rtc_switch_to_bank1(rtc);
tmp = rtc->read(rtc, reg_info->reg) & reg_info->bit;
ds1685_rtc_switch_to_bank0(rtc);
return sprintf(buf, "%d\n", (tmp ? 1 : 0));
}
/**
* ds1685_rtc_sysfs_ctrl_regs_store - writes a ctrl register bit via sysfs.
* @dev: pointer to device structure.
* @attr: pointer to device_attribute structure.
* @buf: pointer to char array to hold the output.
* @count: number of bytes written.
*/
static ssize_t
ds1685_rtc_sysfs_ctrl_regs_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct ds1685_priv *rtc = dev_get_drvdata(dev);
u8 reg = 0, bit = 0, tmp;
unsigned long flags;
long int val = 0;
const struct ds1685_rtc_ctrl_regs *reg_info =
ds1685_rtc_sysfs_ctrl_regs_lookup(attr->attr.name);
/* We only accept numbers. */
if (kstrtol(buf, 10, &val) < 0)
return -EINVAL;
/* bits are binary, 0 or 1 only. */
if ((val != 0) && (val != 1))
return -ERANGE;
/* Make sure we actually matched something. */
if (!reg_info)
return -EINVAL;
reg = reg_info->reg;
bit = reg_info->bit;
/* Safe to spinlock during a write. */
ds1685_rtc_begin_ctrl_access(rtc, &flags);
tmp = rtc->read(rtc, reg);
rtc->write(rtc, reg, (val ? (tmp | bit) : (tmp & ~(bit))));
ds1685_rtc_end_ctrl_access(rtc, flags);
return count;
}
/**
* DS1685_RTC_SYSFS_CTRL_REG_RO - device_attribute for read-only register bit.
* @bit: bit to read.
*/
#define DS1685_RTC_SYSFS_CTRL_REG_RO(bit) \
static DEVICE_ATTR(bit, S_IRUGO, \
ds1685_rtc_sysfs_ctrl_regs_show, NULL)
/**
* DS1685_RTC_SYSFS_CTRL_REG_RW - device_attribute for read-write register bit.
* @bit: bit to read or write.
*/
#define DS1685_RTC_SYSFS_CTRL_REG_RW(bit) \
static DEVICE_ATTR(bit, S_IRUGO | S_IWUSR, \
ds1685_rtc_sysfs_ctrl_regs_show, \
ds1685_rtc_sysfs_ctrl_regs_store)
/*
* Control Register A bits.
*/
DS1685_RTC_SYSFS_CTRL_REG_RO(uip);
DS1685_RTC_SYSFS_CTRL_REG_RW(dv2);
DS1685_RTC_SYSFS_CTRL_REG_RW(dv1);
DS1685_RTC_SYSFS_CTRL_REG_RO(dv0);
DS1685_RTC_SYSFS_CTRL_REG_RW(rs3);
DS1685_RTC_SYSFS_CTRL_REG_RW(rs2);
DS1685_RTC_SYSFS_CTRL_REG_RW(rs1);
DS1685_RTC_SYSFS_CTRL_REG_RW(rs0);
static struct attribute*
ds1685_rtc_sysfs_ctrla_attrs[] = {
&dev_attr_uip.attr,
&dev_attr_dv2.attr,
&dev_attr_dv1.attr,
&dev_attr_dv0.attr,
&dev_attr_rs3.attr,
&dev_attr_rs2.attr,
&dev_attr_rs1.attr,
&dev_attr_rs0.attr,
NULL,
};
static const struct attribute_group
ds1685_rtc_sysfs_ctrla_grp = {
.name = "ctrla",
.attrs = ds1685_rtc_sysfs_ctrla_attrs,
};
/*
* Control Register B bits.
*/
DS1685_RTC_SYSFS_CTRL_REG_RO(set);
DS1685_RTC_SYSFS_CTRL_REG_RW(pie);
DS1685_RTC_SYSFS_CTRL_REG_RW(aie);
DS1685_RTC_SYSFS_CTRL_REG_RW(uie);
DS1685_RTC_SYSFS_CTRL_REG_RW(sqwe);
DS1685_RTC_SYSFS_CTRL_REG_RO(dm);
DS1685_RTC_SYSFS_CTRL_REG_RO(2412);
DS1685_RTC_SYSFS_CTRL_REG_RO(dse);
static struct attribute*
ds1685_rtc_sysfs_ctrlb_attrs[] = {
&dev_attr_set.attr,
&dev_attr_pie.attr,
&dev_attr_aie.attr,
&dev_attr_uie.attr,
&dev_attr_sqwe.attr,
&dev_attr_dm.attr,
&dev_attr_2412.attr,
&dev_attr_dse.attr,
NULL,
};
static const struct attribute_group
ds1685_rtc_sysfs_ctrlb_grp = {
.name = "ctrlb",
.attrs = ds1685_rtc_sysfs_ctrlb_attrs,
};
/*
* Control Register C bits.
*
* Reading Control C clears these bits! Reading them individually can
* possibly cause an interrupt to be missed. Use the /proc interface
* to see all the bits in this register simultaneously.
*/
DS1685_RTC_SYSFS_CTRL_REG_RO(irqf);
DS1685_RTC_SYSFS_CTRL_REG_RO(pf);
DS1685_RTC_SYSFS_CTRL_REG_RO(af);
DS1685_RTC_SYSFS_CTRL_REG_RO(uf);
static struct attribute*
ds1685_rtc_sysfs_ctrlc_attrs[] = {
&dev_attr_irqf.attr,
&dev_attr_pf.attr,
&dev_attr_af.attr,
&dev_attr_uf.attr,
NULL,
};
static const struct attribute_group
ds1685_rtc_sysfs_ctrlc_grp = {
.name = "ctrlc",
.attrs = ds1685_rtc_sysfs_ctrlc_attrs,
};
/*
* Control Register D bits.
*/
DS1685_RTC_SYSFS_CTRL_REG_RO(vrt);
static struct attribute*
ds1685_rtc_sysfs_ctrld_attrs[] = {
&dev_attr_vrt.attr,
NULL,
};
static const struct attribute_group
ds1685_rtc_sysfs_ctrld_grp = {
.name = "ctrld",
.attrs = ds1685_rtc_sysfs_ctrld_attrs,
};
/*
* Control Register 4A bits.
*/
DS1685_RTC_SYSFS_CTRL_REG_RO(vrt2);
DS1685_RTC_SYSFS_CTRL_REG_RO(incr);
DS1685_RTC_SYSFS_CTRL_REG_RW(pab);
DS1685_RTC_SYSFS_CTRL_REG_RW(rf);
DS1685_RTC_SYSFS_CTRL_REG_RW(wf);
DS1685_RTC_SYSFS_CTRL_REG_RW(kf);
#if !defined(CONFIG_RTC_DRV_DS1685) && !defined(CONFIG_RTC_DRV_DS1689)
DS1685_RTC_SYSFS_CTRL_REG_RO(bme);
#endif
static struct attribute*
ds1685_rtc_sysfs_ctrl4a_attrs[] = {
&dev_attr_vrt2.attr,
&dev_attr_incr.attr,
&dev_attr_pab.attr,
&dev_attr_rf.attr,
&dev_attr_wf.attr,
&dev_attr_kf.attr,
#if !defined(CONFIG_RTC_DRV_DS1685) && !defined(CONFIG_RTC_DRV_DS1689)
&dev_attr_bme.attr,
#endif
NULL,
};
static const struct attribute_group
ds1685_rtc_sysfs_ctrl4a_grp = {
.name = "ctrl4a",
.attrs = ds1685_rtc_sysfs_ctrl4a_attrs,
};
/*
* Control Register 4B bits.
*/
DS1685_RTC_SYSFS_CTRL_REG_RW(abe);
DS1685_RTC_SYSFS_CTRL_REG_RW(e32k);
DS1685_RTC_SYSFS_CTRL_REG_RO(cs);
DS1685_RTC_SYSFS_CTRL_REG_RW(rce);
DS1685_RTC_SYSFS_CTRL_REG_RW(prs);
DS1685_RTC_SYSFS_CTRL_REG_RW(rie);
DS1685_RTC_SYSFS_CTRL_REG_RW(wie);
DS1685_RTC_SYSFS_CTRL_REG_RW(kse);
static struct attribute*
ds1685_rtc_sysfs_ctrl4b_attrs[] = {
&dev_attr_abe.attr,
&dev_attr_e32k.attr,
&dev_attr_cs.attr,
&dev_attr_rce.attr,
&dev_attr_prs.attr,
&dev_attr_rie.attr,
&dev_attr_wie.attr,
&dev_attr_kse.attr,
NULL,
};
static const struct attribute_group
ds1685_rtc_sysfs_ctrl4b_grp = {
.name = "ctrl4b",
.attrs = ds1685_rtc_sysfs_ctrl4b_attrs,
};
#endif /* CONFIG_RTC_DS1685_SYSFS_REGS */
/**
* ds1685_rtc_sysfs_register - register sysfs files.
* @dev: pointer to device structure.
@ -1541,31 +1206,6 @@ ds1685_rtc_sysfs_register(struct device *dev)
if (ret)
return ret;
#ifdef CONFIG_RTC_DS1685_SYSFS_REGS
ret = sysfs_create_group(&dev->kobj, &ds1685_rtc_sysfs_ctrla_grp);
if (ret)
return ret;
ret = sysfs_create_group(&dev->kobj, &ds1685_rtc_sysfs_ctrlb_grp);
if (ret)
return ret;
ret = sysfs_create_group(&dev->kobj, &ds1685_rtc_sysfs_ctrlc_grp);
if (ret)
return ret;
ret = sysfs_create_group(&dev->kobj, &ds1685_rtc_sysfs_ctrld_grp);
if (ret)
return ret;
ret = sysfs_create_group(&dev->kobj, &ds1685_rtc_sysfs_ctrl4a_grp);
if (ret)
return ret;
ret = sysfs_create_group(&dev->kobj, &ds1685_rtc_sysfs_ctrl4b_grp);
if (ret)
return ret;
#endif
return 0;
}
@ -1579,15 +1219,6 @@ ds1685_rtc_sysfs_unregister(struct device *dev)
sysfs_remove_bin_file(&dev->kobj, &ds1685_rtc_sysfs_nvram_attr);
sysfs_remove_group(&dev->kobj, &ds1685_rtc_sysfs_misc_grp);
#ifdef CONFIG_RTC_DS1685_SYSFS_REGS
sysfs_remove_group(&dev->kobj, &ds1685_rtc_sysfs_ctrla_grp);
sysfs_remove_group(&dev->kobj, &ds1685_rtc_sysfs_ctrlb_grp);
sysfs_remove_group(&dev->kobj, &ds1685_rtc_sysfs_ctrlc_grp);
sysfs_remove_group(&dev->kobj, &ds1685_rtc_sysfs_ctrld_grp);
sysfs_remove_group(&dev->kobj, &ds1685_rtc_sysfs_ctrl4a_grp);
sysfs_remove_group(&dev->kobj, &ds1685_rtc_sysfs_ctrl4b_grp);
#endif
return 0;
}
#endif /* CONFIG_SYSFS */