rtc: pcf2127: add support for multiple TS functions

This will simplify the implementation of new variants into this driver.

Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-11-hugo@hugovil.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
This commit is contained in:
Hugo Villeneuve 2023-06-22 10:57:53 -04:00 committed by Alexandre Belloni
parent fc16599e01
commit 420cc9e850
1 changed files with 203 additions and 69 deletions

View File

@ -59,8 +59,8 @@
#define PCF2127_BIT_WD_CTL_CD0 BIT(6)
#define PCF2127_BIT_WD_CTL_CD1 BIT(7)
#define PCF2127_REG_WD_VAL 0x11
/* Tamper timestamp registers */
#define PCF2127_REG_TS_CTRL 0x12
/* Tamper timestamp1 registers */
#define PCF2127_REG_TS1_BASE 0x12
#define PCF2127_BIT_TS_CTRL_TSOFF BIT(6)
#define PCF2127_BIT_TS_CTRL_TSM BIT(7)
/*
@ -86,12 +86,36 @@
PCF2127_BIT_CTRL2_WDTF | \
PCF2127_BIT_CTRL2_TSF2)
#define PCF2127_MAX_TS_SUPPORTED 1
enum pcf21xx_type {
PCF2127,
PCF2129,
PCF21XX_LAST_ID
};
struct pcf21xx_ts_config {
u8 reg_base; /* Base register to read timestamp values. */
/*
* If the TS input pin is driven to GND, an interrupt can be generated
* (supported by all variants).
*/
u8 gnd_detect_reg; /* Interrupt control register address. */
u8 gnd_detect_bit; /* Interrupt bit. */
/*
* If the TS input pin is driven to an intermediate level between GND
* and supply, an interrupt can be generated (optional feature depending
* on variant).
*/
u8 inter_detect_reg; /* Interrupt control register address. */
u8 inter_detect_bit; /* Interrupt bit. */
u8 ie_reg; /* Interrupt enable control register. */
u8 ie_bit; /* Interrupt enable bit. */
};
struct pcf21xx_config {
int type; /* IC variant */
int max_register;
@ -102,6 +126,9 @@ struct pcf21xx_config {
u8 reg_wd_ctl; /* Watchdog control register. */
u8 reg_wd_val; /* Watchdog value register. */
u8 reg_clkout; /* Clkout register. */
unsigned int ts_count;
struct pcf21xx_ts_config ts[PCF2127_MAX_TS_SUPPORTED];
struct attribute_group attribute_group;
};
struct pcf2127 {
@ -109,9 +136,9 @@ struct pcf2127 {
struct watchdog_device wdd;
struct regmap *regmap;
const struct pcf21xx_config *cfg;
time64_t ts;
bool ts_valid;
bool irq_enabled;
time64_t ts[PCF2127_MAX_TS_SUPPORTED]; /* Timestamp values. */
bool ts_valid[PCF2127_MAX_TS_SUPPORTED]; /* Timestamp valid indication. */
};
/*
@ -441,18 +468,19 @@ static int pcf2127_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
}
/*
* This function reads ctrl2 register, caller is responsible for calling
* pcf2127_wdt_active_ping()
* This function reads one timestamp function data, caller is responsible for
* calling pcf2127_wdt_active_ping()
*/
static int pcf2127_rtc_ts_read(struct device *dev, time64_t *ts)
static int pcf2127_rtc_ts_read(struct device *dev, time64_t *ts,
int ts_id)
{
struct pcf2127 *pcf2127 = dev_get_drvdata(dev);
struct rtc_time tm;
int ret;
unsigned char data[7];
ret = regmap_bulk_read(pcf2127->regmap, PCF2127_REG_TS_CTRL, data,
sizeof(data));
ret = regmap_bulk_read(pcf2127->regmap, pcf2127->cfg->ts[ts_id].reg_base,
data, sizeof(data));
if (ret) {
dev_err(dev, "%s: read error ret=%d\n", __func__, ret);
return ret;
@ -482,18 +510,21 @@ static int pcf2127_rtc_ts_read(struct device *dev, time64_t *ts)
return 0;
};
static void pcf2127_rtc_ts_snapshot(struct device *dev)
static void pcf2127_rtc_ts_snapshot(struct device *dev, int ts_id)
{
struct pcf2127 *pcf2127 = dev_get_drvdata(dev);
int ret;
/* Let userspace read the first timestamp */
if (pcf2127->ts_valid)
if (ts_id >= pcf2127->cfg->ts_count)
return;
ret = pcf2127_rtc_ts_read(dev, &pcf2127->ts);
/* Let userspace read the first timestamp */
if (pcf2127->ts_valid[ts_id])
return;
ret = pcf2127_rtc_ts_read(dev, &pcf2127->ts[ts_id], ts_id);
if (!ret)
pcf2127->ts_valid = true;
pcf2127->ts_valid[ts_id] = true;
}
static irqreturn_t pcf2127_rtc_irq(int irq, void *dev)
@ -514,7 +545,7 @@ static irqreturn_t pcf2127_rtc_irq(int irq, void *dev)
return IRQ_NONE;
if (ctrl1 & PCF2127_BIT_CTRL1_TSF1 || ctrl2 & PCF2127_BIT_CTRL2_TSF2)
pcf2127_rtc_ts_snapshot(dev);
pcf2127_rtc_ts_snapshot(dev, 0);
if (ctrl1 & PCF2127_CTRL1_IRQ_MASK)
regmap_write(pcf2127->regmap, PCF2127_REG_CTRL1,
@ -543,28 +574,41 @@ static const struct rtc_class_ops pcf2127_rtc_ops = {
/* sysfs interface */
static ssize_t timestamp0_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
static ssize_t timestamp_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count, int ts_id)
{
struct pcf2127 *pcf2127 = dev_get_drvdata(dev->parent);
int ret;
if (ts_id >= pcf2127->cfg->ts_count)
return 0;
if (pcf2127->irq_enabled) {
pcf2127->ts_valid = false;
pcf2127->ts_valid[ts_id] = false;
} else {
ret = regmap_update_bits(pcf2127->regmap, PCF2127_REG_CTRL1,
PCF2127_BIT_CTRL1_TSF1, 0);
/* Always clear GND interrupt bit. */
ret = regmap_update_bits(pcf2127->regmap,
pcf2127->cfg->ts[ts_id].gnd_detect_reg,
pcf2127->cfg->ts[ts_id].gnd_detect_bit,
0);
if (ret) {
dev_err(dev, "%s: update ctrl1 ret=%d\n", __func__, ret);
dev_err(dev, "%s: update TS gnd detect ret=%d\n", __func__, ret);
return ret;
}
ret = regmap_update_bits(pcf2127->regmap, PCF2127_REG_CTRL2,
PCF2127_BIT_CTRL2_TSF2, 0);
if (ret) {
dev_err(dev, "%s: update ctrl2 ret=%d\n", __func__, ret);
return ret;
if (pcf2127->cfg->ts[ts_id].inter_detect_bit) {
/* Clear intermediate level interrupt bit if supported. */
ret = regmap_update_bits(pcf2127->regmap,
pcf2127->cfg->ts[ts_id].inter_detect_reg,
pcf2127->cfg->ts[ts_id].inter_detect_bit,
0);
if (ret) {
dev_err(dev, "%s: update TS intermediate level detect ret=%d\n",
__func__, ret);
return ret;
}
}
ret = pcf2127_wdt_active_ping(&pcf2127->wdd);
@ -573,34 +617,63 @@ static ssize_t timestamp0_store(struct device *dev,
}
return count;
}
static ssize_t timestamp0_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
return timestamp_store(dev, attr, buf, count, 0);
};
static ssize_t timestamp0_show(struct device *dev,
struct device_attribute *attr, char *buf)
static ssize_t timestamp_show(struct device *dev,
struct device_attribute *attr, char *buf,
int ts_id)
{
struct pcf2127 *pcf2127 = dev_get_drvdata(dev->parent);
unsigned int ctrl1, ctrl2;
int ret;
time64_t ts;
if (ts_id >= pcf2127->cfg->ts_count)
return 0;
if (pcf2127->irq_enabled) {
if (!pcf2127->ts_valid)
if (!pcf2127->ts_valid[ts_id])
return 0;
ts = pcf2127->ts;
ts = pcf2127->ts[ts_id];
} else {
ret = regmap_read(pcf2127->regmap, PCF2127_REG_CTRL1, &ctrl1);
u8 valid_low = 0;
u8 valid_inter = 0;
unsigned int ctrl;
/* Check if TS input pin is driven to GND, supported by all
* variants.
*/
ret = regmap_read(pcf2127->regmap,
pcf2127->cfg->ts[ts_id].gnd_detect_reg,
&ctrl);
if (ret)
return 0;
ret = regmap_read(pcf2127->regmap, PCF2127_REG_CTRL2, &ctrl2);
if (ret)
valid_low = ctrl & pcf2127->cfg->ts[ts_id].gnd_detect_bit;
if (pcf2127->cfg->ts[ts_id].inter_detect_bit) {
/* Check if TS input pin is driven to intermediate level
* between GND and supply, if supported by variant.
*/
ret = regmap_read(pcf2127->regmap,
pcf2127->cfg->ts[ts_id].inter_detect_reg,
&ctrl);
if (ret)
return 0;
valid_inter = ctrl & pcf2127->cfg->ts[ts_id].inter_detect_bit;
}
if (!valid_low && !valid_inter)
return 0;
if (!(ctrl1 & PCF2127_BIT_CTRL1_TSF1) &&
!(ctrl2 & PCF2127_BIT_CTRL2_TSF2))
return 0;
ret = pcf2127_rtc_ts_read(dev->parent, &ts);
ret = pcf2127_rtc_ts_read(dev->parent, &ts, ts_id);
if (ret)
return 0;
@ -609,6 +682,12 @@ static ssize_t timestamp0_show(struct device *dev,
return ret;
}
return sprintf(buf, "%llu\n", (unsigned long long)ts);
}
static ssize_t timestamp0_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return timestamp_show(dev, attr, buf, 0);
};
static DEVICE_ATTR_RW(timestamp0);
@ -618,10 +697,6 @@ static struct attribute *pcf2127_attrs[] = {
NULL
};
static const struct attribute_group pcf2127_attr_group = {
.attrs = pcf2127_attrs,
};
static struct pcf21xx_config pcf21xx_cfg[] = {
[PCF2127] = {
.type = PCF2127,
@ -633,6 +708,19 @@ static struct pcf21xx_config pcf21xx_cfg[] = {
.reg_wd_ctl = PCF2127_REG_WD_CTL,
.reg_wd_val = PCF2127_REG_WD_VAL,
.reg_clkout = PCF2127_REG_CLKOUT,
.ts_count = 1,
.ts[0] = {
.reg_base = PCF2127_REG_TS1_BASE,
.gnd_detect_reg = PCF2127_REG_CTRL1,
.gnd_detect_bit = PCF2127_BIT_CTRL1_TSF1,
.inter_detect_reg = PCF2127_REG_CTRL2,
.inter_detect_bit = PCF2127_BIT_CTRL2_TSF2,
.ie_reg = PCF2127_REG_CTRL2,
.ie_bit = PCF2127_BIT_CTRL2_TSIE,
},
.attribute_group = {
.attrs = pcf2127_attrs,
},
},
[PCF2129] = {
.type = PCF2129,
@ -644,9 +732,74 @@ static struct pcf21xx_config pcf21xx_cfg[] = {
.reg_wd_ctl = PCF2127_REG_WD_CTL,
.reg_wd_val = PCF2127_REG_WD_VAL,
.reg_clkout = PCF2127_REG_CLKOUT,
.ts_count = 1,
.ts[0] = {
.reg_base = PCF2127_REG_TS1_BASE,
.gnd_detect_reg = PCF2127_REG_CTRL1,
.gnd_detect_bit = PCF2127_BIT_CTRL1_TSF1,
.inter_detect_reg = PCF2127_REG_CTRL2,
.inter_detect_bit = PCF2127_BIT_CTRL2_TSF2,
.ie_reg = PCF2127_REG_CTRL2,
.ie_bit = PCF2127_BIT_CTRL2_TSIE,
},
.attribute_group = {
.attrs = pcf2127_attrs,
},
},
};
/*
* Enable timestamp function and corresponding interrupt(s).
*/
static int pcf2127_enable_ts(struct device *dev, int ts_id)
{
struct pcf2127 *pcf2127 = dev_get_drvdata(dev);
int ret;
if (ts_id >= pcf2127->cfg->ts_count) {
dev_err(dev, "%s: invalid tamper detection ID (%d)\n",
__func__, ts_id);
return -EINVAL;
}
/* Enable timestamp function. */
ret = regmap_update_bits(pcf2127->regmap,
pcf2127->cfg->ts[ts_id].reg_base,
PCF2127_BIT_TS_CTRL_TSOFF |
PCF2127_BIT_TS_CTRL_TSM,
PCF2127_BIT_TS_CTRL_TSM);
if (ret) {
dev_err(dev, "%s: tamper detection config (ts%d_ctrl) failed\n",
__func__, ts_id);
return ret;
}
/* TS input pin driven to GND detection is supported by all variants.
* Make sure that interrupt bit is defined.
*/
if (pcf2127->cfg->ts[ts_id].gnd_detect_bit == 0) {
dev_err(dev, "%s: tamper detection to GND configuration invalid\n",
__func__);
return ret;
}
/*
* Enable interrupt generation when TSF timestamp flag is set.
* Interrupt signals are open-drain outputs and can be left floating if
* unused.
*/
ret = regmap_update_bits(pcf2127->regmap, pcf2127->cfg->ts[ts_id].ie_reg,
pcf2127->cfg->ts[ts_id].ie_bit,
pcf2127->cfg->ts[ts_id].ie_bit);
if (ret) {
dev_err(dev, "%s: tamper detection TSIE%d config failed\n",
__func__, ts_id);
return ret;
}
return ret;
}
static int pcf2127_probe(struct device *dev, struct regmap *regmap,
int alarm_irq, const char *name, const struct pcf21xx_config *config)
{
@ -777,34 +930,15 @@ static int pcf2127_probe(struct device *dev, struct regmap *regmap,
}
/*
* Enable timestamp function and store timestamp of first trigger
* event until TSF1 and TSF2 interrupt flags are cleared.
* Enable timestamp functions 1 to 4.
*/
ret = regmap_update_bits(pcf2127->regmap, PCF2127_REG_TS_CTRL,
PCF2127_BIT_TS_CTRL_TSOFF |
PCF2127_BIT_TS_CTRL_TSM,
PCF2127_BIT_TS_CTRL_TSM);
if (ret) {
dev_err(dev, "%s: tamper detection config (ts_ctrl) failed\n",
__func__);
return ret;
for (int i = 0; i < pcf2127->cfg->ts_count; i++) {
ret = pcf2127_enable_ts(dev, i);
if (ret)
return ret;
}
/*
* Enable interrupt generation when TSF1 or TSF2 timestamp flags
* are set. Interrupt signal is an open-drain output and can be
* left floating if unused.
*/
ret = regmap_update_bits(pcf2127->regmap, PCF2127_REG_CTRL2,
PCF2127_BIT_CTRL2_TSIE,
PCF2127_BIT_CTRL2_TSIE);
if (ret) {
dev_err(dev, "%s: tamper detection config (ctrl2) failed\n",
__func__);
return ret;
}
ret = rtc_add_group(pcf2127->rtc, &pcf2127_attr_group);
ret = rtc_add_group(pcf2127->rtc, &pcf2127->cfg->attribute_group);
if (ret) {
dev_err(dev, "%s: tamper sysfs registering failed\n",
__func__);