rtc: m41t80: replace i2c functions for smbus ones
The driver used i2c_transfer methods to read and set date/time.
The smbus methods should be used.
This commit replaces i2c_transfer functions by i2c_smbus_XX_i2c_block_data
for reading and setting the datetime.
Signed-off-by: Mylène Josserand <mylene.josserand@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
diff --git a/drivers/rtc/rtc-m41t80.c b/drivers/rtc/rtc-m41t80.c
index cc8b93d..1a76927 100644
--- a/drivers/rtc/rtc-m41t80.c
+++ b/drivers/rtc/rtc-m41t80.c
@@ -32,21 +32,21 @@
#include <linux/watchdog.h>
#endif
-#define M41T80_REG_SSEC 0
-#define M41T80_REG_SEC 1
-#define M41T80_REG_MIN 2
-#define M41T80_REG_HOUR 3
-#define M41T80_REG_WDAY 4
-#define M41T80_REG_DAY 5
-#define M41T80_REG_MON 6
-#define M41T80_REG_YEAR 7
-#define M41T80_REG_ALARM_MON 0xa
-#define M41T80_REG_ALARM_DAY 0xb
-#define M41T80_REG_ALARM_HOUR 0xc
-#define M41T80_REG_ALARM_MIN 0xd
-#define M41T80_REG_ALARM_SEC 0xe
-#define M41T80_REG_FLAGS 0xf
-#define M41T80_REG_SQW 0x13
+#define M41T80_REG_SSEC 0x00
+#define M41T80_REG_SEC 0x01
+#define M41T80_REG_MIN 0x02
+#define M41T80_REG_HOUR 0x03
+#define M41T80_REG_WDAY 0x04
+#define M41T80_REG_DAY 0x05
+#define M41T80_REG_MON 0x06
+#define M41T80_REG_YEAR 0x07
+#define M41T80_REG_ALARM_MON 0x0a
+#define M41T80_REG_ALARM_DAY 0x0b
+#define M41T80_REG_ALARM_HOUR 0x0c
+#define M41T80_REG_ALARM_MIN 0x0d
+#define M41T80_REG_ALARM_SEC 0x0e
+#define M41T80_REG_FLAGS 0x0f
+#define M41T80_REG_SQW 0x13
#define M41T80_DATETIME_REG_SIZE (M41T80_REG_YEAR + 1)
#define M41T80_ALARM_REG_SIZE \
@@ -93,24 +93,13 @@
static int m41t80_get_datetime(struct i2c_client *client,
struct rtc_time *tm)
{
- u8 buf[M41T80_DATETIME_REG_SIZE], dt_addr[1] = { M41T80_REG_SEC };
- struct i2c_msg msgs[] = {
- {
- .addr = client->addr,
- .flags = 0,
- .len = 1,
- .buf = dt_addr,
- },
- {
- .addr = client->addr,
- .flags = I2C_M_RD,
- .len = M41T80_DATETIME_REG_SIZE - M41T80_REG_SEC,
- .buf = buf + M41T80_REG_SEC,
- },
- };
+ unsigned char buf[8];
+ int err;
- if (i2c_transfer(client->adapter, msgs, 2) < 0) {
- dev_err(&client->dev, "read error\n");
+ err = i2c_smbus_read_i2c_block_data(client, M41T80_REG_SSEC,
+ sizeof(buf), buf);
+ if (err < 0) {
+ dev_err(&client->dev, "Unable to read date\n");
return -EIO;
}
@@ -129,67 +118,29 @@
/* Sets the given date and time to the real time clock. */
static int m41t80_set_datetime(struct i2c_client *client, struct rtc_time *tm)
{
- u8 wbuf[1 + M41T80_DATETIME_REG_SIZE];
- u8 *buf = &wbuf[1];
- u8 dt_addr[1] = { M41T80_REG_SEC };
- struct i2c_msg msgs_in[] = {
- {
- .addr = client->addr,
- .flags = 0,
- .len = 1,
- .buf = dt_addr,
- },
- {
- .addr = client->addr,
- .flags = I2C_M_RD,
- .len = M41T80_DATETIME_REG_SIZE - M41T80_REG_SEC,
- .buf = buf + M41T80_REG_SEC,
- },
- };
- struct i2c_msg msgs[] = {
- {
- .addr = client->addr,
- .flags = 0,
- .len = 1 + M41T80_DATETIME_REG_SIZE,
- .buf = wbuf,
- },
- };
+ unsigned char buf[8];
+ int err;
- /* Read current reg values into buf[1..7] */
- if (i2c_transfer(client->adapter, msgs_in, 2) < 0) {
- dev_err(&client->dev, "read error\n");
- return -EIO;
- }
-
- wbuf[0] = 0; /* offset into rtc's regs */
- /* Merge time-data and register flags into buf[0..7] */
- buf[M41T80_REG_SSEC] = 0;
- buf[M41T80_REG_SEC] =
- bin2bcd(tm->tm_sec) | (buf[M41T80_REG_SEC] & ~0x7f);
- buf[M41T80_REG_MIN] =
- bin2bcd(tm->tm_min) | (buf[M41T80_REG_MIN] & ~0x7f);
- buf[M41T80_REG_HOUR] =
- bin2bcd(tm->tm_hour) | (buf[M41T80_REG_HOUR] & ~0x3f);
- buf[M41T80_REG_WDAY] =
- (tm->tm_wday & 0x07) | (buf[M41T80_REG_WDAY] & ~0x07);
- buf[M41T80_REG_DAY] =
- bin2bcd(tm->tm_mday) | (buf[M41T80_REG_DAY] & ~0x3f);
- buf[M41T80_REG_MON] =
- bin2bcd(tm->tm_mon + 1) | (buf[M41T80_REG_MON] & ~0x1f);
-
- /* assume 20YY not 19YY */
- if (tm->tm_year < 100 || tm->tm_year > 199) {
- dev_err(&client->dev, "Year must be between 2000 and 2099. It's %d.\n",
- tm->tm_year + 1900);
+ if (tm->tm_year < 100 || tm->tm_year > 199)
return -EINVAL;
- }
- buf[M41T80_REG_YEAR] = bin2bcd(tm->tm_year % 100);
- if (i2c_transfer(client->adapter, msgs, 1) != 1) {
- dev_err(&client->dev, "write error\n");
- return -EIO;
+ buf[M41T80_REG_SSEC] = 0;
+ buf[M41T80_REG_SEC] = bin2bcd(tm->tm_sec);
+ buf[M41T80_REG_MIN] = bin2bcd(tm->tm_min);
+ buf[M41T80_REG_HOUR] = bin2bcd(tm->tm_hour);
+ buf[M41T80_REG_DAY] = bin2bcd(tm->tm_mday);
+ buf[M41T80_REG_MON] = bin2bcd(tm->tm_mon + 1);
+ buf[M41T80_REG_YEAR] = bin2bcd(tm->tm_year - 100);
+ buf[M41T80_REG_WDAY] = tm->tm_wday;
+
+ err = i2c_smbus_write_i2c_block_data(client, M41T80_REG_SSEC,
+ sizeof(buf), buf);
+ if (err < 0) {
+ dev_err(&client->dev, "Unable to write to date registers\n");
+ return err;
}
- return 0;
+
+ return err;
}
static int m41t80_rtc_proc(struct device *dev, struct seq_file *seq)
@@ -631,14 +582,17 @@
static int m41t80_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
+ struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
int rc = 0;
struct rtc_device *rtc = NULL;
struct rtc_time tm;
struct m41t80_data *clientdata = NULL;
- if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C
- | I2C_FUNC_SMBUS_BYTE_DATA))
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_I2C_BLOCK |
+ I2C_FUNC_SMBUS_BYTE_DATA)) {
+ dev_err(&adapter->dev, "doesn't support I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_I2C_BLOCK\n");
return -ENODEV;
+ }
clientdata = devm_kzalloc(&client->dev, sizeof(*clientdata),
GFP_KERNEL);