summaryrefslogtreecommitdiffstats
path: root/drivers/rtc/rtc-max6900.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/rtc/rtc-max6900.c')
-rw-r--r--drivers/rtc/rtc-max6900.c223
1 files changed, 69 insertions, 154 deletions
diff --git a/drivers/rtc/rtc-max6900.c b/drivers/rtc/rtc-max6900.c
index ded3c0abad8..12c9cd25cad 100644
--- a/drivers/rtc/rtc-max6900.c
+++ b/drivers/rtc/rtc-max6900.c
@@ -17,19 +17,18 @@
#include <linux/rtc.h>
#include <linux/delay.h>
-#define DRV_NAME "max6900"
-#define DRV_VERSION "0.1"
+#define DRV_VERSION "0.2"
/*
* register indices
*/
-#define MAX6900_REG_SC 0 /* seconds 00-59 */
-#define MAX6900_REG_MN 1 /* minutes 00-59 */
-#define MAX6900_REG_HR 2 /* hours 00-23 */
-#define MAX6900_REG_DT 3 /* day of month 00-31 */
-#define MAX6900_REG_MO 4 /* month 01-12 */
-#define MAX6900_REG_DW 5 /* day of week 1-7 */
-#define MAX6900_REG_YR 6 /* year 00-99 */
+#define MAX6900_REG_SC 0 /* seconds 00-59 */
+#define MAX6900_REG_MN 1 /* minutes 00-59 */
+#define MAX6900_REG_HR 2 /* hours 00-23 */
+#define MAX6900_REG_DT 3 /* day of month 00-31 */
+#define MAX6900_REG_MO 4 /* month 01-12 */
+#define MAX6900_REG_DW 5 /* day of week 1-7 */
+#define MAX6900_REG_YR 6 /* year 00-99 */
#define MAX6900_REG_CT 7 /* control */
/* register 8 is undocumented */
#define MAX6900_REG_CENTURY 9 /* century */
@@ -39,7 +38,6 @@
#define MAX6900_REG_CT_WP (1 << 7) /* Write Protect */
-
/*
* register read/write commands
*/
@@ -52,16 +50,7 @@
#define MAX6900_IDLE_TIME_AFTER_WRITE 3 /* specification says 2.5 mS */
-#define MAX6900_I2C_ADDR 0xa0
-
-static const unsigned short normal_i2c[] = {
- MAX6900_I2C_ADDR >> 1,
- I2C_CLIENT_END
-};
-
-I2C_CLIENT_INSMOD; /* defines addr_data */
-
-static int max6900_probe(struct i2c_adapter *adapter, int addr, int kind);
+static struct i2c_driver max6900_driver;
static int max6900_i2c_read_regs(struct i2c_client *client, u8 *buf)
{
@@ -69,36 +58,35 @@ static int max6900_i2c_read_regs(struct i2c_client *client, u8 *buf)
u8 reg_century_read[1] = { MAX6900_REG_CENTURY_READ };
struct i2c_msg msgs[4] = {
{
- .addr = client->addr,
- .flags = 0, /* write */
- .len = sizeof(reg_burst_read),
- .buf = reg_burst_read
- },
+ .addr = client->addr,
+ .flags = 0, /* write */
+ .len = sizeof(reg_burst_read),
+ .buf = reg_burst_read}
+ ,
{
- .addr = client->addr,
- .flags = I2C_M_RD,
- .len = MAX6900_BURST_LEN,
- .buf = buf
- },
+ .addr = client->addr,
+ .flags = I2C_M_RD,
+ .len = MAX6900_BURST_LEN,
+ .buf = buf}
+ ,
{
- .addr = client->addr,
- .flags = 0, /* write */
- .len = sizeof(reg_century_read),
- .buf = reg_century_read
- },
+ .addr = client->addr,
+ .flags = 0, /* write */
+ .len = sizeof(reg_century_read),
+ .buf = reg_century_read}
+ ,
{
- .addr = client->addr,
- .flags = I2C_M_RD,
- .len = sizeof(buf[MAX6900_REG_CENTURY]),
- .buf = &buf[MAX6900_REG_CENTURY]
- }
+ .addr = client->addr,
+ .flags = I2C_M_RD,
+ .len = sizeof(buf[MAX6900_REG_CENTURY]),
+ .buf = &buf[MAX6900_REG_CENTURY]
+ }
};
int rc;
rc = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
if (rc != ARRAY_SIZE(msgs)) {
- dev_err(&client->dev, "%s: register read failed\n",
- __func__);
+ dev_err(&client->dev, "%s: register read failed\n", __func__);
return -EIO;
}
return 0;
@@ -109,20 +97,18 @@ static int max6900_i2c_write_regs(struct i2c_client *client, u8 const *buf)
u8 i2c_century_buf[1 + 1] = { MAX6900_REG_CENTURY_WRITE };
struct i2c_msg century_msgs[1] = {
{
- .addr = client->addr,
- .flags = 0, /* write */
- .len = sizeof(i2c_century_buf),
- .buf = i2c_century_buf
- }
+ .addr = client->addr,
+ .flags = 0, /* write */
+ .len = sizeof(i2c_century_buf),
+ .buf = i2c_century_buf}
};
u8 i2c_burst_buf[MAX6900_BURST_LEN + 1] = { MAX6900_REG_BURST_WRITE };
struct i2c_msg burst_msgs[1] = {
{
- .addr = client->addr,
- .flags = 0, /* write */
- .len = sizeof(i2c_burst_buf),
- .buf = i2c_burst_buf
- }
+ .addr = client->addr,
+ .flags = 0, /* write */
+ .len = sizeof(i2c_burst_buf),
+ .buf = i2c_burst_buf}
};
int rc;
@@ -133,10 +119,12 @@ static int max6900_i2c_write_regs(struct i2c_client *client, u8 const *buf)
* bit as part of the burst write.
*/
i2c_century_buf[1] = buf[MAX6900_REG_CENTURY];
+
rc = i2c_transfer(client->adapter, century_msgs,
ARRAY_SIZE(century_msgs));
if (rc != ARRAY_SIZE(century_msgs))
goto write_failed;
+
msleep(MAX6900_IDLE_TIME_AFTER_WRITE);
memcpy(&i2c_burst_buf[1], buf, MAX6900_BURST_LEN);
@@ -148,45 +136,11 @@ static int max6900_i2c_write_regs(struct i2c_client *client, u8 const *buf)
return 0;
-write_failed:
- dev_err(&client->dev, "%s: register write failed\n",
- __func__);
+ write_failed:
+ dev_err(&client->dev, "%s: register write failed\n", __func__);
return -EIO;
}
-static int max6900_i2c_validate_client(struct i2c_client *client)
-{
- u8 regs[MAX6900_REG_LEN];
- u8 zero_mask[] = {
- 0x80, /* seconds */
- 0x80, /* minutes */
- 0x40, /* hours */
- 0xc0, /* day of month */
- 0xe0, /* month */
- 0xf8, /* day of week */
- 0x00, /* year */
- 0x7f, /* control */
- };
- int i;
- int rc;
- int reserved;
-
- reserved = i2c_smbus_read_byte_data(client, MAX6900_REG_RESERVED_READ);
- if (reserved != 0x07)
- return -ENODEV;
-
- rc = max6900_i2c_read_regs(client, regs);
- if (rc < 0)
- return rc;
-
- for (i = 0; i < ARRAY_SIZE(zero_mask); ++i) {
- if (regs[i] & zero_mask[i])
- return -ENODEV;
- }
-
- return 0;
-}
-
static int max6900_i2c_read_time(struct i2c_client *client, struct rtc_time *tm)
{
int rc;
@@ -202,7 +156,7 @@ static int max6900_i2c_read_time(struct i2c_client *client, struct rtc_time *tm)
tm->tm_mday = BCD2BIN(regs[MAX6900_REG_DT]);
tm->tm_mon = BCD2BIN(regs[MAX6900_REG_MO]) - 1;
tm->tm_year = BCD2BIN(regs[MAX6900_REG_YR]) +
- BCD2BIN(regs[MAX6900_REG_CENTURY]) * 100 - 1900;
+ BCD2BIN(regs[MAX6900_REG_CENTURY]) * 100 - 1900;
tm->tm_wday = BCD2BIN(regs[MAX6900_REG_DW]);
return 0;
@@ -211,7 +165,7 @@ static int max6900_i2c_read_time(struct i2c_client *client, struct rtc_time *tm)
static int max6900_i2c_clear_write_protect(struct i2c_client *client)
{
int rc;
- rc = i2c_smbus_write_byte_data (client, MAX6900_REG_CONTROL_WRITE, 0);
+ rc = i2c_smbus_write_byte_data(client, MAX6900_REG_CONTROL_WRITE, 0);
if (rc < 0) {
dev_err(&client->dev, "%s: control register write failed\n",
__func__);
@@ -220,8 +174,8 @@ static int max6900_i2c_clear_write_protect(struct i2c_client *client)
return 0;
}
-static int max6900_i2c_set_time(struct i2c_client *client,
- struct rtc_time const *tm)
+static int
+max6900_i2c_set_time(struct i2c_client *client, struct rtc_time const *tm)
{
u8 regs[MAX6900_REG_LEN];
int rc;
@@ -258,89 +212,49 @@ static int max6900_rtc_set_time(struct device *dev, struct rtc_time *tm)
return max6900_i2c_set_time(to_i2c_client(dev), tm);
}
-static int max6900_attach_adapter(struct i2c_adapter *adapter)
-{
- return i2c_probe(adapter, &addr_data, max6900_probe);
-}
-
-static int max6900_detach_client(struct i2c_client *client)
+static int max6900_remove(struct i2c_client *client)
{
- struct rtc_device *const rtc = i2c_get_clientdata(client);
+ struct rtc_device *rtc = i2c_get_clientdata(client);
if (rtc)
rtc_device_unregister(rtc);
- return i2c_detach_client(client);
+ return 0;
}
-static struct i2c_driver max6900_driver = {
- .driver = {
- .name = DRV_NAME,
- },
- .id = I2C_DRIVERID_MAX6900,
- .attach_adapter = max6900_attach_adapter,
- .detach_client = max6900_detach_client,
-};
-
static const struct rtc_class_ops max6900_rtc_ops = {
- .read_time = max6900_rtc_read_time,
- .set_time = max6900_rtc_set_time,
+ .read_time = max6900_rtc_read_time,
+ .set_time = max6900_rtc_set_time,
};
-static int max6900_probe(struct i2c_adapter *adapter, int addr, int kind)
+static int
+max6900_probe(struct i2c_client *client, const struct i2c_device_id *id)
{
- int rc = 0;
- struct i2c_client *client = NULL;
- struct rtc_device *rtc = NULL;
-
- if (!i2c_check_functionality(adapter, I2C_FUNC_I2C)) {
- rc = -ENODEV;
- goto failout;
- }
-
- client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL);
- if (client == NULL) {
- rc = -ENOMEM;
- goto failout;
- }
-
- client->addr = addr;
- client->adapter = adapter;
- client->driver = &max6900_driver;
- strlcpy(client->name, DRV_NAME, I2C_NAME_SIZE);
-
- if (kind < 0) {
- rc = max6900_i2c_validate_client(client);
- if (rc < 0)
- goto failout;
- }
+ struct rtc_device *rtc;
- rc = i2c_attach_client(client);
- if (rc < 0)
- goto failout;
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
+ return -ENODEV;
- dev_info(&client->dev,
- "chip found, driver version " DRV_VERSION "\n");
+ dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n");
rtc = rtc_device_register(max6900_driver.driver.name,
- &client->dev,
- &max6900_rtc_ops, THIS_MODULE);
- if (IS_ERR(rtc)) {
- rc = PTR_ERR(rtc);
- goto failout_detach;
- }
+ &client->dev, &max6900_rtc_ops, THIS_MODULE);
+ if (IS_ERR(rtc))
+ return PTR_ERR(rtc);
i2c_set_clientdata(client, rtc);
return 0;
-
-failout_detach:
- i2c_detach_client(client);
-failout:
- kfree(client);
- return rc;
}
+static struct i2c_driver max6900_driver = {
+ .driver = {
+ .name = "rtc-max6900",
+ },
+ .probe = max6900_probe,
+ .remove = max6900_remove,
+};
+
static int __init max6900_init(void)
{
return i2c_add_driver(&max6900_driver);
@@ -352,6 +266,7 @@ static void __exit max6900_exit(void)
}
MODULE_DESCRIPTION("Maxim MAX6900 RTC driver");
+MODULE_AUTHOR("Dale Farnsworth <dale@farnsworth.org>");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-16 18:18:50 +0000