[PATCH 8/8] rtc: rx8010: convert to using regmap

Bartosz Golaszewski
2020-09-04T15:22:03Z

This driver requires SMBUS to work. We can relax this requirement if we
switch to using i2c regmap and let the regmap sub-system figure out how
to talk to the bus.

This also has the advantage of shrinking the code for register updates.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
---
drivers/rtc/rtc-rx8010.c | 200 ++++++++++++++++-----------------------
1 file changed, 81 insertions(+), 119 deletions(-)

diff --git a/drivers/rtc/rtc-rx8010.c b/drivers/rtc/rtc-rx8010.c
index ed8ba38b4991..9be3ea88e86d 100644
--- a/drivers/rtc/rtc-rx8010.c
+++ b/drivers/rtc/rtc-rx8010.c
@@ -11,6 +11,7 @@
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/regmap.h>
#include <linux/rtc.h>

#define RX8010_SEC 0x10
@@ -63,7 +64,7 @@ static const struct of_device_id rx8010_of_match[] = {
MODULE_DEVICE_TABLE(of, rx8010_of_match);

struct rx8010_data {
- struct i2c_client *client;
+ struct regmap *regs;
struct rtc_device *rtc;
u8 ctrlreg;
};
@@ -72,13 +73,12 @@ static irqreturn_t rx8010_irq_1_handler(int irq, void *dev_id)
{
struct i2c_client *client = dev_id;
struct rx8010_data *rx8010 = i2c_get_clientdata(client);
- int flagreg;
+ int flagreg, err;

mutex_lock(&rx8010->rtc->ops_lock);

- flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG);
-
- if (flagreg <= 0) {
+ err = regmap_read(rx8010->regs, RX8010_FLAG, &flagreg);
+ if (err) {
mutex_unlock(&rx8010->rtc->ops_lock);
return IRQ_NONE;
}
@@ -101,10 +101,9 @@ static irqreturn_t rx8010_irq_1_handler(int irq, void *dev_id)
rtc_update_irq(rx8010->rtc, 1, RTC_UF | RTC_IRQF);
}

- i2c_smbus_write_byte_data(client, RX8010_FLAG, flagreg);
-
+ err = regmap_write(rx8010->regs, RX8010_FLAG, flagreg);
mutex_unlock(&rx8010->rtc->ops_lock);
- return IRQ_HANDLED;
+ return err ? IRQ_NONE : IRQ_HANDLED;
}

static int rx8010_get_time(struct device *dev, struct rtc_time *dt)
@@ -113,19 +112,19 @@ static int rx8010_get_time(struct device *dev, struct rtc_time *dt)
u8 date[RX8010_TIME_BUF_LEN];
int flagreg, err;

- flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG);
- if (flagreg < 0)
- return flagreg;
+ err = regmap_read(rx8010->regs, RX8010_FLAG, &flagreg);
+ if (err)
+ return err;

if (flagreg & RX8010_FLAG_VLF) {
dev_warn(dev, "Frequency stop detected\n");
return -EINVAL;
}

- err = i2c_smbus_read_i2c_block_data(rx8010->client, RX8010_SEC,
- RX8010_TIME_BUF_LEN, date);
- if (err != RX8010_TIME_BUF_LEN)
- return err < 0 ? err : -EIO;
+ err = regmap_bulk_read(rx8010->regs, RX8010_SEC,
+ date, RX8010_TIME_BUF_LEN);
+ if (err)
+ return err;

dt->tm_sec = bcd2bin(date[RX8010_SEC - RX8010_SEC] & 0x7f);
dt->tm_min = bcd2bin(date[RX8010_MIN - RX8010_SEC] & 0x7f);
@@ -142,19 +141,14 @@ static int rx8010_set_time(struct device *dev, struct rtc_time *dt)
{
struct rx8010_data *rx8010 = dev_get_drvdata(dev);
u8 date[RX8010_TIME_BUF_LEN];
- int ctrl, flagreg, err;
+ int err;

if ((dt->tm_year < 100) || (dt->tm_year > 199))
return -EINVAL;

/* set STOP bit before changing clock/calendar */
- ctrl = i2c_smbus_read_byte_data(rx8010->client, RX8010_CTRL);
- if (ctrl < 0)
- return ctrl;
- rx8010->ctrlreg = ctrl | RX8010_CTRL_STOP;
- err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
- rx8010->ctrlreg);
- if (err < 0)
+ err = regmap_set_bits(rx8010->regs, RX8010_CTRL, RX8010_CTRL_STOP);
+ if (err)
return err;

date[RX8010_SEC - RX8010_SEC] = bin2bcd(dt->tm_sec);
@@ -165,66 +159,55 @@ static int rx8010_set_time(struct device *dev, struct rtc_time *dt)
date[RX8010_YEAR - RX8010_SEC] = bin2bcd(dt->tm_year - 100);
date[RX8010_WDAY - RX8010_SEC] = bin2bcd(1 << dt->tm_wday);

- err = i2c_smbus_write_i2c_block_data(rx8010->client,
- RX8010_SEC, RX8010_TIME_BUF_LEN,
- date);
- if (err < 0)
+ err = regmap_bulk_write(rx8010->regs, RX8010_SEC,
+ date, RX8010_TIME_BUF_LEN);
+ if (err)
return err;

/* clear STOP bit after changing clock/calendar */
- ctrl = i2c_smbus_read_byte_data(rx8010->client, RX8010_CTRL);
- if (ctrl < 0)
- return ctrl;
- rx8010->ctrlreg = ctrl & ~RX8010_CTRL_STOP;
- err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
- rx8010->ctrlreg);
- if (err < 0)
+ err = regmap_clear_bits(rx8010->regs, RX8010_CTRL, RX8010_CTRL_STOP);
+ if (err)
return err;

- flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG);
- if (flagreg < 0)
- return flagreg;
-
- if (flagreg & RX8010_FLAG_VLF)
- err = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG,
- flagreg & ~RX8010_FLAG_VLF);
+ err = regmap_clear_bits(rx8010->regs, RX8010_FLAG, RX8010_FLAG_VLF);
+ if (err)
+ return err;

return 0;
}

-static int rx8010_init_client(struct i2c_client *client)
+static int rx8010_init_client(struct device *dev)
{
- struct rx8010_data *rx8010 = i2c_get_clientdata(client);
+ struct rx8010_data *rx8010 = dev_get_drvdata(dev);
u8 ctrl[2];
int need_clear = 0, err;

/* Initialize reserved registers as specified in datasheet */
- err = i2c_smbus_write_byte_data(client, RX8010_RESV17, 0xD8);
- if (err < 0)
+ err = regmap_write(rx8010->regs, RX8010_RESV17, 0xD8);
+ if (err)
return err;

- err = i2c_smbus_write_byte_data(client, RX8010_RESV30, 0x00);
- if (err < 0)
+ err = regmap_write(rx8010->regs, RX8010_RESV30, 0x00);
+ if (err)
return err;

- err = i2c_smbus_write_byte_data(client, RX8010_RESV31, 0x08);
- if (err < 0)
+ err = regmap_write(rx8010->regs, RX8010_RESV31, 0x08);
+ if (err)
return err;

- err = i2c_smbus_write_byte_data(client, RX8010_IRQ, 0x00);
- if (err < 0)
+ err = regmap_write(rx8010->regs, RX8010_IRQ, 0x00);
+ if (err)
return err;

- err = i2c_smbus_read_i2c_block_data(rx8010->client, RX8010_FLAG,
- 2, ctrl);
- if (err != 2)
- return err < 0 ? err : -EIO;
+ err = regmap_bulk_read(rx8010->regs, RX8010_FLAG, ctrl, 2);
+ if (err)
+ return err;

if (ctrl[0] & RX8010_FLAG_VLF)
- dev_warn(&client->dev, "Frequency stop was detected\n");
+ dev_warn(dev, "Frequency stop was detected\n");

if (ctrl[0] & RX8010_FLAG_AF) {
- dev_warn(&client->dev, "Alarm was detected\n");
+ dev_warn(dev, "Alarm was detected\n");
need_clear = 1;
}

@@ -236,8 +219,8 @@ static int rx8010_init_client(struct i2c_client *client)

if (need_clear) {
ctrl[0] &= ~(RX8010_FLAG_AF | RX8010_FLAG_TF | RX8010_FLAG_UF);
- err = i2c_smbus_write_byte_data(client, RX8010_FLAG, ctrl[0]);
- if (err < 0)
+ err = regmap_write(rx8010->regs, RX8010_FLAG, ctrl[0]);
+ if (err)
return err;
}

@@ -249,17 +232,16 @@ static int rx8010_init_client(struct i2c_client *client)
static int rx8010_read_alarm(struct device *dev, struct rtc_wkalrm *t)
{
struct rx8010_data *rx8010 = dev_get_drvdata(dev);
- struct i2c_client *client = rx8010->client;
u8 alarmvals[3];
int flagreg, err;

- err = i2c_smbus_read_i2c_block_data(client, RX8010_ALMIN, 3, alarmvals);
- if (err != 3)
- return err < 0 ? err : -EIO;
+ err = regmap_bulk_read(rx8010->regs, RX8010_ALMIN, alarmvals, 3);
+ if (err)
+ return err;

- flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG);
- if (flagreg < 0)
- return flagreg;
+ err = regmap_read(rx8010->regs, RX8010_FLAG, &flagreg);
+ if (err)
+ return err;

t->time.tm_sec = 0;
t->time.tm_min = bcd2bin(alarmvals[0] & 0x7f);
@@ -276,52 +258,38 @@ static int rx8010_read_alarm(struct device *dev, struct rtc_wkalrm *t)

static int rx8010_set_alarm(struct device *dev, struct rtc_wkalrm *t)
{
- struct i2c_client *client = to_i2c_client(dev);
struct rx8010_data *rx8010 = dev_get_drvdata(dev);
u8 alarmvals[3];
- int extreg, flagreg, err;
-
- flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG);
- if (flagreg < 0)
- return flagreg;
+ int err;

if (rx8010->ctrlreg & (RX8010_CTRL_AIE | RX8010_CTRL_UIE)) {
rx8010->ctrlreg &= ~(RX8010_CTRL_AIE | RX8010_CTRL_UIE);
- err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
- rx8010->ctrlreg);
- if (err < 0)
+ err = regmap_write(rx8010->regs, RX8010_CTRL, rx8010->ctrlreg);
+ if (err)
return err;
}

- flagreg &= ~RX8010_FLAG_AF;
- err = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG, flagreg);
- if (err < 0)
+ err = regmap_clear_bits(rx8010->regs, RX8010_FLAG, RX8010_FLAG_AF);
+ if (err)
return err;

alarmvals[0] = bin2bcd(t->time.tm_min);
alarmvals[1] = bin2bcd(t->time.tm_hour);
alarmvals[2] = bin2bcd(t->time.tm_mday);

- err = i2c_smbus_write_i2c_block_data(rx8010->client, RX8010_ALMIN,
- 2, alarmvals);
- if (err < 0)
+ err = regmap_bulk_write(rx8010->regs, RX8010_ALMIN, alarmvals, 2);
+ if (err)
return err;

- extreg = i2c_smbus_read_byte_data(client, RX8010_EXT);
- if (extreg < 0)
- return extreg;
-
- extreg |= RX8010_EXT_WADA;
- err = i2c_smbus_write_byte_data(rx8010->client, RX8010_EXT, extreg);
- if (err < 0)
+ err = regmap_clear_bits(rx8010->regs, RX8010_EXT, RX8010_EXT_WADA);
+ if (err)
return err;

if (alarmvals[2] == 0)
alarmvals[2] |= RX8010_ALARM_AE;

- err = i2c_smbus_write_byte_data(rx8010->client, RX8010_ALWDAY,
- alarmvals[2]);
- if (err < 0)
+ err = regmap_write(rx8010->regs, RX8010_ALWDAY, alarmvals[2]);
+ if (err)
return err;

if (t->enabled) {
@@ -331,9 +299,8 @@ static int rx8010_set_alarm(struct device *dev, struct rtc_wkalrm *t)
rx8010->ctrlreg |=
(RX8010_CTRL_AIE | RX8010_CTRL_UIE);

- err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
- rx8010->ctrlreg);
- if (err < 0)
+ err = regmap_write(rx8010->regs, RX8010_CTRL, rx8010->ctrlreg);
+ if (err)
return err;
}

@@ -343,9 +310,8 @@ static int rx8010_set_alarm(struct device *dev, struct rtc_wkalrm *t)
static int rx8010_alarm_irq_enable(struct device *dev,
unsigned int enabled)
{
- struct i2c_client *client = to_i2c_client(dev);
struct rx8010_data *rx8010 = dev_get_drvdata(dev);
- int flagreg, err;
+ int err;
u8 ctrl;

ctrl = rx8010->ctrlreg;
@@ -362,20 +328,14 @@ static int rx8010_alarm_irq_enable(struct device *dev,
ctrl &= ~RX8010_CTRL_AIE;
}

- flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG);
- if (flagreg < 0)
- return flagreg;
-
- flagreg &= ~RX8010_FLAG_AF;
- err = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG, flagreg);
- if (err < 0)
+ err = regmap_clear_bits(rx8010->regs, RX8010_FLAG, RX8010_FLAG_AF);
+ if (err)
return err;

if (ctrl != rx8010->ctrlreg) {
rx8010->ctrlreg = ctrl;
- err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
- rx8010->ctrlreg);
- if (err < 0)
+ err = regmap_write(rx8010->regs, RX8010_CTRL, rx8010->ctrlreg);
+ if (err)
return err;
}

@@ -385,13 +345,13 @@ static int rx8010_alarm_irq_enable(struct device *dev,
static int rx8010_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
{
struct rx8010_data *rx8010 = dev_get_drvdata(dev);
- int tmp, flagreg;
+ int tmp, flagreg, err;

switch (cmd) {
case RTC_VL_READ:
- flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG);
- if (flagreg < 0)
- return flagreg;
+ err = regmap_read(rx8010->regs, RX8010_FLAG, &flagreg);
+ if (err)
+ return err;

tmp = flagreg & RX8010_FLAG_VLF ? RTC_VL_DATA_INVALID : 0;
return put_user(tmp, (unsigned int __user *)arg);
@@ -407,28 +367,30 @@ static struct rtc_class_ops rx8010_rtc_ops = {
.ioctl = rx8010_ioctl,
};

+static const struct regmap_config rx8010_regmap_config = {
+ .name = "rx8010-rtc",
+ .reg_bits = 8,
+ .val_bits = 8,
+};
+
static int rx8010_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
- struct i2c_adapter *adapter = client->adapter;
struct rx8010_data *rx8010;
int err = 0;

- if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
- | I2C_FUNC_SMBUS_I2C_BLOCK)) {
- dev_err(&adapter->dev, "doesn't support required functionality\n");
- return -EIO;
- }
-
rx8010 = devm_kzalloc(&client->dev, sizeof(struct rx8010_data),
GFP_KERNEL);
if (!rx8010)
return -ENOMEM;

- rx8010->client = client;
i2c_set_clientdata(client, rx8010);

- err = rx8010_init_client(client);
+ rx8010->regs = devm_regmap_init_i2c(client, &rx8010_regmap_config);
+ if (IS_ERR(rx8010->regs))
+ return PTR_ERR(rx8010->regs);
+
+ err = rx8010_init_client(&client->dev);
if (err)
return err;

--
2.26.1