rtc: abx80x: add alarm support

Add alarm support to the abx80x driver.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

diff --git a/drivers/rtc/rtc-abx80x.c b/drivers/rtc/rtc-abx80x.c
index 203e6616d413fd7fc053577f4b13779bb7d806fc..d41bbcd653f6cbdd30c270bc2b0181050ad0749c 100644 (file)
--- a/drivers/rtc/rtc-abx80x.c
+++ b/drivers/rtc/rtc-abx80x.c
@@ -27,10 +27,28 @@
 #define ABX8XX_REG_YR          0x06
 #define ABX8XX_REG_WD          0x07
 
+#define ABX8XX_REG_AHTH                0x08
+#define ABX8XX_REG_ASC         0x09
+#define ABX8XX_REG_AMN         0x0a
+#define ABX8XX_REG_AHR         0x0b
+#define ABX8XX_REG_ADA         0x0c
+#define ABX8XX_REG_AMO         0x0d
+#define ABX8XX_REG_AWD         0x0e
+
+#define ABX8XX_REG_STATUS      0x0f
+#define ABX8XX_STATUS_AF       BIT(2)
+
 #define ABX8XX_REG_CTRL1       0x10
 #define ABX8XX_CTRL_WRITE      BIT(0)
+#define ABX8XX_CTRL_ARST       BIT(2)
 #define ABX8XX_CTRL_12_24      BIT(6)
 
+#define ABX8XX_REG_IRQ         0x12
+#define ABX8XX_IRQ_AIE         BIT(2)
+#define ABX8XX_IRQ_IM_1_4      (0x3 << 5)
+
+#define ABX8XX_REG_CD_TIMER_CTL        0x18
+
 #define ABX8XX_REG_CFG_KEY     0x1f
 #define ABX8XX_CFG_KEY_MISC    0x9d
 
@@ -63,8 +81,6 @@ static struct abx80x_cap abx80x_caps[] = {
        [ABX80X] = {.pn = 0}
 };
 
-static struct i2c_driver abx80x_driver;
-
 static int abx80x_enable_trickle_charger(struct i2c_client *client,
                                         u8 trickle_cfg)
 {
@@ -148,9 +164,111 @@ static int abx80x_rtc_set_time(struct device *dev, struct rtc_time *tm)
        return 0;
 }
 
+static irqreturn_t abx80x_handle_irq(int irq, void *dev_id)
+{
+       struct i2c_client *client = dev_id;
+       struct rtc_device *rtc = i2c_get_clientdata(client);
+       int status;
+
+       status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS);
+       if (status < 0)
+               return IRQ_NONE;
+
+       if (status & ABX8XX_STATUS_AF)
+               rtc_update_irq(rtc, 1, RTC_AF | RTC_IRQF);
+
+       i2c_smbus_write_byte_data(client, ABX8XX_REG_STATUS, 0);
+
+       return IRQ_HANDLED;
+}
+
+static int abx80x_read_alarm(struct device *dev, struct rtc_wkalrm *t)
+{
+       struct i2c_client *client = to_i2c_client(dev);
+       unsigned char buf[7];
+
+       int irq_mask, err;
+
+       if (client->irq <= 0)
+               return -EINVAL;
+
+       err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_ASC,
+                                           sizeof(buf), buf);
+       if (err)
+               return err;
+
+       irq_mask = i2c_smbus_read_byte_data(client, ABX8XX_REG_IRQ);
+       if (irq_mask < 0)
+               return irq_mask;
+
+       t->time.tm_sec = bcd2bin(buf[0] & 0x7F);
+       t->time.tm_min = bcd2bin(buf[1] & 0x7F);
+       t->time.tm_hour = bcd2bin(buf[2] & 0x3F);
+       t->time.tm_mday = bcd2bin(buf[3] & 0x3F);
+       t->time.tm_mon = bcd2bin(buf[4] & 0x1F) - 1;
+       t->time.tm_wday = buf[5] & 0x7;
+
+       t->enabled = !!(irq_mask & ABX8XX_IRQ_AIE);
+       t->pending = (buf[6] & ABX8XX_STATUS_AF) && t->enabled;
+
+       return err;
+}
+
+static int abx80x_set_alarm(struct device *dev, struct rtc_wkalrm *t)
+{
+       struct i2c_client *client = to_i2c_client(dev);
+       u8 alarm[6];
+       int err;
+
+       if (client->irq <= 0)
+               return -EINVAL;
+
+       alarm[0] = 0x0;
+       alarm[1] = bin2bcd(t->time.tm_sec);
+       alarm[2] = bin2bcd(t->time.tm_min);
+       alarm[3] = bin2bcd(t->time.tm_hour);
+       alarm[4] = bin2bcd(t->time.tm_mday);
+       alarm[5] = bin2bcd(t->time.tm_mon + 1);
+
+       err = i2c_smbus_write_i2c_block_data(client, ABX8XX_REG_AHTH,
+                                            sizeof(alarm), alarm);
+       if (err < 0) {
+               dev_err(&client->dev, "Unable to write alarm registers\n");
+               return -EIO;
+       }
+
+       if (t->enabled) {
+               err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,
+                                               (ABX8XX_IRQ_IM_1_4 |
+                                                ABX8XX_IRQ_AIE));
+               if (err)
+                       return err;
+       }
+
+       return 0;
+}
+
+static int abx80x_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+       struct i2c_client *client = to_i2c_client(dev);
+       int err;
+
+       if (enabled)
+               err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,
+                                               (ABX8XX_IRQ_IM_1_4 |
+                                                ABX8XX_IRQ_AIE));
+       else
+               err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,
+                                               ABX8XX_IRQ_IM_1_4);
+       return err;
+}
+
 static const struct rtc_class_ops abx80x_rtc_ops = {
        .read_time      = abx80x_rtc_read_time,
        .set_time       = abx80x_rtc_set_time,
+       .read_alarm     = abx80x_read_alarm,
+       .set_alarm      = abx80x_set_alarm,
+       .alarm_irq_enable = abx80x_alarm_irq_enable,
 };
 
 static int abx80x_dt_trickle_cfg(struct device_node *np)
@@ -225,7 +343,8 @@ static int abx80x_probe(struct i2c_client *client,
        }
 
        err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CTRL1,
-                                       ((data & ~ABX8XX_CTRL_12_24) |
+                                       ((data & ~(ABX8XX_CTRL_12_24 |
+                                                  ABX8XX_CTRL_ARST)) |
                                         ABX8XX_CTRL_WRITE));
        if (err < 0) {
                dev_err(&client->dev, "Unable to write control register\n");
@@ -260,7 +379,12 @@ static int abx80x_probe(struct i2c_client *client,
                abx80x_enable_trickle_charger(client, trickle_cfg);
        }
 
-       rtc = devm_rtc_device_register(&client->dev, abx80x_driver.driver.name,
+       err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CD_TIMER_CTL,
+                                       BIT(2));
+       if (err)
+               return err;
+
+       rtc = devm_rtc_device_register(&client->dev, "abx8xx",
                                       &abx80x_rtc_ops, THIS_MODULE);
 
        if (IS_ERR(rtc))
@@ -268,6 +392,19 @@ static int abx80x_probe(struct i2c_client *client,
 
        i2c_set_clientdata(client, rtc);
 
+       if (client->irq > 0) {
+               dev_info(&client->dev, "IRQ %d supplied\n", client->irq);
+               err = devm_request_threaded_irq(&client->dev, client->irq, NULL,
+                                               abx80x_handle_irq,
+                                               IRQF_SHARED | IRQF_ONESHOT,
+                                               "abx8xx",
+                                               client);
+               if (err) {
+                       dev_err(&client->dev, "unable to request IRQ, alarms disabled\n");
+                       client->irq = 0;
+               }
+       }
+
        return 0;
 }