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path: root/drivers/rtc/rtc-m41t80.c
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Diffstat (limited to 'drivers/rtc/rtc-m41t80.c')
-rw-r--r--drivers/rtc/rtc-m41t80.c151
1 files changed, 54 insertions, 97 deletions
diff --git a/drivers/rtc/rtc-m41t80.c b/drivers/rtc/rtc-m41t80.c
index 8940e9e43ea0..c90fba3ed861 100644
--- a/drivers/rtc/rtc-m41t80.c
+++ b/drivers/rtc/rtc-m41t80.c
@@ -154,6 +154,8 @@ struct m41t80_data {
struct rtc_device *rtc;
#ifdef CONFIG_COMMON_CLK
struct clk_hw sqw;
+ unsigned long freq;
+ unsigned int sqwe;
#endif
};
@@ -440,68 +442,43 @@ static int m41t80_resume(struct device *dev)
static SIMPLE_DEV_PM_OPS(m41t80_pm, m41t80_suspend, m41t80_resume);
-static ssize_t flags_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- struct i2c_client *client = to_i2c_client(dev);
- int val;
-
- val = i2c_smbus_read_byte_data(client, M41T80_REG_FLAGS);
- if (val < 0)
- return val;
- return sprintf(buf, "%#x\n", val);
-}
-static DEVICE_ATTR_RO(flags);
-
-static struct attribute *attrs[] = {
- &dev_attr_flags.attr,
- NULL,
-};
-
-static struct attribute_group attr_group = {
- .attrs = attrs,
-};
-
#ifdef CONFIG_COMMON_CLK
#define sqw_to_m41t80_data(_hw) container_of(_hw, struct m41t80_data, sqw)
-static unsigned long m41t80_sqw_recalc_rate(struct clk_hw *hw,
- unsigned long parent_rate)
+static unsigned long m41t80_decode_freq(int setting)
+{
+ return (setting == 0) ? 0 : (setting == 1) ? M41T80_SQW_MAX_FREQ :
+ M41T80_SQW_MAX_FREQ >> setting;
+}
+
+static unsigned long m41t80_get_freq(struct m41t80_data *m41t80)
{
- struct m41t80_data *m41t80 = sqw_to_m41t80_data(hw);
struct i2c_client *client = m41t80->client;
int reg_sqw = (m41t80->features & M41T80_FEATURE_SQ_ALT) ?
M41T80_REG_WDAY : M41T80_REG_SQW;
int ret = i2c_smbus_read_byte_data(client, reg_sqw);
- unsigned long val = M41T80_SQW_MAX_FREQ;
if (ret < 0)
return 0;
+ return m41t80_decode_freq(ret >> 4);
+}
- ret >>= 4;
- if (ret == 0)
- val = 0;
- else if (ret > 1)
- val = val / (1 << ret);
-
- return val;
+static unsigned long m41t80_sqw_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ return sqw_to_m41t80_data(hw)->freq;
}
static long m41t80_sqw_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *prate)
{
- int i, freq = M41T80_SQW_MAX_FREQ;
-
- if (freq <= rate)
- return freq;
-
- for (i = 2; i <= ilog2(M41T80_SQW_MAX_FREQ); i++) {
- freq /= 1 << i;
- if (freq <= rate)
- return freq;
- }
-
- return 0;
+ if (rate >= M41T80_SQW_MAX_FREQ)
+ return M41T80_SQW_MAX_FREQ;
+ if (rate >= M41T80_SQW_MAX_FREQ / 4)
+ return M41T80_SQW_MAX_FREQ / 4;
+ if (!rate)
+ return 0;
+ return 1 << ilog2(rate);
}
static int m41t80_sqw_set_rate(struct clk_hw *hw, unsigned long rate,
@@ -513,17 +490,12 @@ static int m41t80_sqw_set_rate(struct clk_hw *hw, unsigned long rate,
M41T80_REG_WDAY : M41T80_REG_SQW;
int reg, ret, val = 0;
- if (rate) {
- if (!is_power_of_2(rate))
- return -EINVAL;
- val = ilog2(rate);
- if (val == ilog2(M41T80_SQW_MAX_FREQ))
- val = 1;
- else if (val < (ilog2(M41T80_SQW_MAX_FREQ) - 1))
- val = ilog2(M41T80_SQW_MAX_FREQ) - val;
- else
- return -EINVAL;
- }
+ if (rate >= M41T80_SQW_MAX_FREQ)
+ val = 1;
+ else if (rate >= M41T80_SQW_MAX_FREQ / 4)
+ val = 2;
+ else if (rate)
+ val = 15 - ilog2(rate);
reg = i2c_smbus_read_byte_data(client, reg_sqw);
if (reg < 0)
@@ -532,10 +504,9 @@ static int m41t80_sqw_set_rate(struct clk_hw *hw, unsigned long rate,
reg = (reg & 0x0f) | (val << 4);
ret = i2c_smbus_write_byte_data(client, reg_sqw, reg);
- if (ret < 0)
- return ret;
-
- return -EINVAL;
+ if (!ret)
+ m41t80->freq = m41t80_decode_freq(val);
+ return ret;
}
static int m41t80_sqw_control(struct clk_hw *hw, bool enable)
@@ -552,7 +523,10 @@ static int m41t80_sqw_control(struct clk_hw *hw, bool enable)
else
ret &= ~M41T80_ALMON_SQWE;
- return i2c_smbus_write_byte_data(client, M41T80_REG_ALARM_MON, ret);
+ ret = i2c_smbus_write_byte_data(client, M41T80_REG_ALARM_MON, ret);
+ if (!ret)
+ m41t80->sqwe = enable;
+ return ret;
}
static int m41t80_sqw_prepare(struct clk_hw *hw)
@@ -567,14 +541,7 @@ static void m41t80_sqw_unprepare(struct clk_hw *hw)
static int m41t80_sqw_is_prepared(struct clk_hw *hw)
{
- struct m41t80_data *m41t80 = sqw_to_m41t80_data(hw);
- struct i2c_client *client = m41t80->client;
- int ret = i2c_smbus_read_byte_data(client, M41T80_REG_ALARM_MON);
-
- if (ret < 0)
- return ret;
-
- return !!(ret & M41T80_ALMON_SQWE);
+ return sqw_to_m41t80_data(hw)->sqwe;
}
static const struct clk_ops m41t80_sqw_ops = {
@@ -609,6 +576,7 @@ static struct clk *m41t80_sqw_register_clk(struct m41t80_data *m41t80)
init.parent_names = NULL;
init.num_parents = 0;
m41t80->sqw.init = &init;
+ m41t80->freq = m41t80_get_freq(m41t80);
/* optional override of the clockname */
of_property_read_string(node, "clock-output-names", &init.name);
@@ -912,13 +880,6 @@ static struct notifier_block wdt_notifier = {
*****************************************************************************
*/
-static void m41t80_remove_sysfs_group(void *_dev)
-{
- struct device *dev = _dev;
-
- sysfs_remove_group(&dev->kobj, &attr_group);
-}
-
static int m41t80_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
@@ -927,6 +888,7 @@ static int m41t80_probe(struct i2c_client *client,
struct rtc_device *rtc = NULL;
struct rtc_time tm;
struct m41t80_data *m41t80_data = NULL;
+ bool wakeup_source = false;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_I2C_BLOCK |
I2C_FUNC_SMBUS_BYTE_DATA)) {
@@ -947,6 +909,10 @@ static int m41t80_probe(struct i2c_client *client,
m41t80_data->features = id->driver_data;
i2c_set_clientdata(client, m41t80_data);
+#ifdef CONFIG_OF
+ wakeup_source = of_property_read_bool(client->dev.of_node,
+ "wakeup-source");
+#endif
if (client->irq > 0) {
rc = devm_request_threaded_irq(&client->dev, client->irq,
NULL, m41t80_handle_irq,
@@ -955,14 +921,16 @@ static int m41t80_probe(struct i2c_client *client,
if (rc) {
dev_warn(&client->dev, "unable to request IRQ, alarms disabled\n");
client->irq = 0;
- } else {
- m41t80_rtc_ops.read_alarm = m41t80_read_alarm;
- m41t80_rtc_ops.set_alarm = m41t80_set_alarm;
- m41t80_rtc_ops.alarm_irq_enable = m41t80_alarm_irq_enable;
- /* Enable the wakealarm */
- device_init_wakeup(&client->dev, true);
+ wakeup_source = false;
}
}
+ if (client->irq > 0 || wakeup_source) {
+ m41t80_rtc_ops.read_alarm = m41t80_read_alarm;
+ m41t80_rtc_ops.set_alarm = m41t80_set_alarm;
+ m41t80_rtc_ops.alarm_irq_enable = m41t80_alarm_irq_enable;
+ /* Enable the wakealarm */
+ device_init_wakeup(&client->dev, true);
+ }
rtc = devm_rtc_device_register(&client->dev, client->name,
&m41t80_rtc_ops, THIS_MODULE);
@@ -970,6 +938,10 @@ static int m41t80_probe(struct i2c_client *client,
return PTR_ERR(rtc);
m41t80_data->rtc = rtc;
+ if (client->irq <= 0) {
+ /* We cannot support UIE mode if we do not have an IRQ line */
+ rtc->uie_unsupported = 1;
+ }
/* Make sure HT (Halt Update) bit is cleared */
rc = i2c_smbus_read_byte_data(client, M41T80_REG_ALARM_HOUR);
@@ -1004,21 +976,6 @@ static int m41t80_probe(struct i2c_client *client,
return rc;
}
- /* Export sysfs entries */
- rc = sysfs_create_group(&(&client->dev)->kobj, &attr_group);
- if (rc) {
- dev_err(&client->dev, "Failed to create sysfs group: %d\n", rc);
- return rc;
- }
-
- rc = devm_add_action_or_reset(&client->dev, m41t80_remove_sysfs_group,
- &client->dev);
- if (rc) {
- dev_err(&client->dev,
- "Failed to add sysfs cleanup action: %d\n", rc);
- return rc;
- }
-
#ifdef CONFIG_RTC_DRV_M41T80_WDT
if (m41t80_data->features & M41T80_FEATURE_HT) {
save_client = client;
generated by cgit v1.2.3 (git 2.46.0) at 2025-09-08 01:20:35 +0000