Merge tag 'rtc-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
 "It is now possible to add custom sysfs attributes while avoiding a
  possible race condition. Unused code has been removed resulting in a
  nice reduction of the code base. And more drivers have been switched
  to SPDX by their maintainers.

 Summary:

  Subsystem:
   - new helpers to add custom sysfs attributes
   - struct rtc_task removal along with rtc_irq_[un]register()
   - rtc_irq_set_state and rtc_irq_set_freq are not exported anymore

  Drivers:
   - armada38x: reset after rtc power loss
   - ds1307: now supports m41t11
   - isl1208: now supports isl1219 and tamper detection
   - pcf2127: internal SRAM support"

* tag 'rtc-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (34 commits)
  rtc: ds1307: simplify hwmon config
  rtc: s5m: Add SPDX license identifier
  rtc: maxim: Add SPDX license identifiers
  rtc: isl1219: add device tree documentation
  rtc: isl1208: set ev-evienb bit from device tree
  rtc: isl1208: Add "evdet" interrupt source for isl1219
  rtc: isl1208: add support for isl1219 with tamper detection
  rtc: sysfs: facilitate attribute add to rtc device
  rtc: remove struct rtc_task
  char: rtc: remove task handling
  rtc: pcf85063: preserve control register value between stop and start
  rtc: sh: remove unused variable rtc_dev
  rtc: unexport rtc_irq_set_*
  rtc: simplify rtc_irq_set_state/rtc_irq_set_freq
  rtc: remove irq_task and irq_task_lock
  rtc: remove rtc_irq_register/rtc_irq_unregister
  rtc: sh: remove dead code
  rtc: sa1100: don't set PIE frequency
  rtc: ds1307: support m41t11 variant
  rtc: ds1307: fix data pointer to m41t0
  ...

1 files changed, 169 insertions, 23 deletions

diff --git a/drivers/rtc/rtc-isl1208.c b/drivers/rtc/rtc-isl1208.c
index 1a2c38cc0178..ea18a8f4bce0 100644
--- a/drivers/rtc/rtc-isl1208.c
+++ b/drivers/rtc/rtc-isl1208.c
@@ -14,6 +14,8 @@
 #include <linux/i2c.h>
 #include <linux/bcd.h>
 #include <linux/rtc.h>
+#include "rtc-core.h"
+#include <linux/of_irq.h>
 
 /* Register map */
 /* rtc section */
@@ -33,13 +35,16 @@
 #define ISL1208_REG_SR_ARST    (1<<7)	/* auto reset */
 #define ISL1208_REG_SR_XTOSCB  (1<<6)	/* crystal oscillator */
 #define ISL1208_REG_SR_WRTC    (1<<4)	/* write rtc */
+#define ISL1208_REG_SR_EVT     (1<<3)	/* event */
 #define ISL1208_REG_SR_ALM     (1<<2)	/* alarm */
 #define ISL1208_REG_SR_BAT     (1<<1)	/* battery */
 #define ISL1208_REG_SR_RTCF    (1<<0)	/* rtc fail */
 #define ISL1208_REG_INT 0x08
 #define ISL1208_REG_INT_ALME   (1<<6)   /* alarm enable */
 #define ISL1208_REG_INT_IM     (1<<7)   /* interrupt/alarm mode */
-#define ISL1208_REG_09  0x09	/* reserved */
+#define ISL1219_REG_EV  0x09
+#define ISL1219_REG_EV_EVEN    (1<<4)   /* event detection enable */
+#define ISL1219_REG_EV_EVIENB  (1<<7)   /* event in pull-up disable */
 #define ISL1208_REG_ATR 0x0a
 #define ISL1208_REG_DTR 0x0b
 
@@ -57,8 +62,24 @@
 #define ISL1208_REG_USR2 0x13
 #define ISL1208_USR_SECTION_LEN 2
 
+/* event section */
+#define ISL1219_REG_SCT 0x14
+#define ISL1219_REG_MNT 0x15
+#define ISL1219_REG_HRT 0x16
+#define ISL1219_REG_DTT 0x17
+#define ISL1219_REG_MOT 0x18
+#define ISL1219_REG_YRT 0x19
+#define ISL1219_EVT_SECTION_LEN 6
+
 static struct i2c_driver isl1208_driver;
 
+/* ISL1208 various variants */
+enum {
+	TYPE_ISL1208 = 0,
+	TYPE_ISL1218,
+	TYPE_ISL1219,
+};
+
 /* block read */
 static int
 isl1208_i2c_read_regs(struct i2c_client *client, u8 reg, u8 buf[],
@@ -80,8 +101,8 @@ isl1208_i2c_read_regs(struct i2c_client *client, u8 reg, u8 buf[],
 	};
 	int ret;
 
-	BUG_ON(reg > ISL1208_REG_USR2);
-	BUG_ON(reg + len > ISL1208_REG_USR2 + 1);
+	WARN_ON(reg > ISL1219_REG_YRT);
+	WARN_ON(reg + len > ISL1219_REG_YRT + 1);
 
 	ret = i2c_transfer(client->adapter, msgs, 2);
 	if (ret > 0)
@@ -104,8 +125,8 @@ isl1208_i2c_set_regs(struct i2c_client *client, u8 reg, u8 const buf[],
 	};
 	int ret;
 
-	BUG_ON(reg > ISL1208_REG_USR2);
-	BUG_ON(reg + len > ISL1208_REG_USR2 + 1);
+	WARN_ON(reg > ISL1219_REG_YRT);
+	WARN_ON(reg + len > ISL1219_REG_YRT + 1);
 
 	i2c_buf[0] = reg;
 	memcpy(&i2c_buf[1], &buf[0], len);
@@ -493,6 +514,73 @@ isl1208_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 	return isl1208_i2c_set_alarm(to_i2c_client(dev), alarm);
 }
 
+static ssize_t timestamp0_store(struct device *dev,
+				struct device_attribute *attr,
+				const char *buf, size_t count)
+{
+	struct i2c_client *client = dev_get_drvdata(dev);
+	int sr;
+
+	sr = isl1208_i2c_get_sr(client);
+	if (sr < 0) {
+		dev_err(dev, "%s: reading SR failed\n", __func__);
+		return sr;
+	}
+
+	sr &= ~ISL1208_REG_SR_EVT;
+
+	sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR, sr);
+	if (sr < 0)
+		dev_err(dev, "%s: writing SR failed\n",
+			__func__);
+
+	return count;
+};
+
+static ssize_t timestamp0_show(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	struct i2c_client *client = dev_get_drvdata(dev);
+	u8 regs[ISL1219_EVT_SECTION_LEN] = { 0, };
+	struct rtc_time tm;
+	int sr;
+
+	sr = isl1208_i2c_get_sr(client);
+	if (sr < 0) {
+		dev_err(dev, "%s: reading SR failed\n", __func__);
+		return sr;
+	}
+
+	if (!(sr & ISL1208_REG_SR_EVT))
+		return 0;
+
+	sr = isl1208_i2c_read_regs(client, ISL1219_REG_SCT, regs,
+				   ISL1219_EVT_SECTION_LEN);
+	if (sr < 0) {
+		dev_err(dev, "%s: reading event section failed\n",
+			__func__);
+		return 0;
+	}
+
+	/* MSB of each alarm register is an enable bit */
+	tm.tm_sec = bcd2bin(regs[ISL1219_REG_SCT - ISL1219_REG_SCT] & 0x7f);
+	tm.tm_min = bcd2bin(regs[ISL1219_REG_MNT - ISL1219_REG_SCT] & 0x7f);
+	tm.tm_hour = bcd2bin(regs[ISL1219_REG_HRT - ISL1219_REG_SCT] & 0x3f);
+	tm.tm_mday = bcd2bin(regs[ISL1219_REG_DTT - ISL1219_REG_SCT] & 0x3f);
+	tm.tm_mon =
+		bcd2bin(regs[ISL1219_REG_MOT - ISL1219_REG_SCT] & 0x1f) - 1;
+	tm.tm_year = bcd2bin(regs[ISL1219_REG_YRT - ISL1219_REG_SCT]) + 100;
+
+	sr = rtc_valid_tm(&tm);
+	if (sr)
+		return sr;
+
+	return sprintf(buf, "%llu\n",
+				(unsigned long long)rtc_tm_to_time64(&tm));
+};
+
+static DEVICE_ATTR_RW(timestamp0);
+
 static irqreturn_t
 isl1208_rtc_interrupt(int irq, void *data)
 {
@@ -538,6 +626,13 @@ isl1208_rtc_interrupt(int irq, void *data)
 			return err;
 	}
 
+	if (sr & ISL1208_REG_SR_EVT) {
+		sysfs_notify(&rtc->dev.kobj, NULL,
+			     dev_attr_timestamp0.attr.name);
+		dev_warn(&client->dev, "event detected");
+		handled = 1;
+	}
+
 	return handled ? IRQ_HANDLED : IRQ_NONE;
 }
 
@@ -623,11 +718,39 @@ static const struct attribute_group isl1208_rtc_sysfs_files = {
 	.attrs	= isl1208_rtc_attrs,
 };
 
+static struct attribute *isl1219_rtc_attrs[] = {
+	&dev_attr_timestamp0.attr,
+	NULL
+};
+
+static const struct attribute_group isl1219_rtc_sysfs_files = {
+	.attrs	= isl1219_rtc_attrs,
+};
+
+static int isl1208_setup_irq(struct i2c_client *client, int irq)
+{
+	int rc = devm_request_threaded_irq(&client->dev, irq, NULL,
+					isl1208_rtc_interrupt,
+					IRQF_SHARED | IRQF_ONESHOT,
+					isl1208_driver.driver.name,
+					client);
+	if (!rc) {
+		device_init_wakeup(&client->dev, 1);
+		enable_irq_wake(irq);
+	} else {
+		dev_err(&client->dev,
+			"Unable to request irq %d, no alarm support\n",
+			irq);
+	}
+	return rc;
+}
+
 static int
 isl1208_probe(struct i2c_client *client, const struct i2c_device_id *id)
 {
 	int rc = 0;
 	struct rtc_device *rtc;
+	int evdet_irq = -1;
 
 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
 		return -ENODEV;
@@ -642,6 +765,7 @@ isl1208_probe(struct i2c_client *client, const struct i2c_device_id *id)
 	rtc->ops = &isl1208_rtc_ops;
 
 	i2c_set_clientdata(client, rtc);
+	dev_set_drvdata(&rtc->dev, client);
 
 	rc = isl1208_i2c_get_sr(client);
 	if (rc < 0) {
@@ -653,26 +777,46 @@ isl1208_probe(struct i2c_client *client, const struct i2c_device_id *id)
 		dev_warn(&client->dev, "rtc power failure detected, "
 			 "please set clock.\n");
 
+	if (id->driver_data == TYPE_ISL1219) {
+		struct device_node *np = client->dev.of_node;
+		u32 evienb;
+
+		rc = i2c_smbus_read_byte_data(client, ISL1219_REG_EV);
+		if (rc < 0) {
+			dev_err(&client->dev, "failed to read EV reg\n");
+			return rc;
+		}
+		rc |= ISL1219_REG_EV_EVEN;
+		if (!of_property_read_u32(np, "isil,ev-evienb", &evienb)) {
+			if (evienb)
+				rc |= ISL1219_REG_EV_EVIENB;
+			else
+				rc &= ~ISL1219_REG_EV_EVIENB;
+		}
+		rc = i2c_smbus_write_byte_data(client, ISL1219_REG_EV, rc);
+		if (rc < 0) {
+			dev_err(&client->dev, "could not enable tamper detection\n");
+			return rc;
+		}
+		rc = rtc_add_group(rtc, &isl1219_rtc_sysfs_files);
+		if (rc)
+			return rc;
+		evdet_irq = of_irq_get_byname(np, "evdet");
+	}
+
 	rc = sysfs_create_group(&client->dev.kobj, &isl1208_rtc_sysfs_files);
 	if (rc)
 		return rc;
 
-	if (client->irq > 0) {
-		rc = devm_request_threaded_irq(&client->dev, client->irq, NULL,
-					       isl1208_rtc_interrupt,
-					       IRQF_SHARED | IRQF_ONESHOT,
-					       isl1208_driver.driver.name,
-					       client);
-		if (!rc) {
-			device_init_wakeup(&client->dev, 1);
-			enable_irq_wake(client->irq);
-		} else {
-			dev_err(&client->dev,
-				"Unable to request irq %d, no alarm support\n",
-				client->irq);
-			client->irq = 0;
-		}
-	}
+	if (client->irq > 0)
+		rc = isl1208_setup_irq(client, client->irq);
+	if (rc)
+		return rc;
+
+	if (evdet_irq > 0 && evdet_irq != client->irq)
+		rc = isl1208_setup_irq(client, evdet_irq);
+	if (rc)
+		return rc;
 
 	return rtc_register_device(rtc);
 }
@@ -686,8 +830,9 @@ isl1208_remove(struct i2c_client *client)
 }
 
 static const struct i2c_device_id isl1208_id[] = {
-	{ "isl1208", 0 },
-	{ "isl1218", 0 },
+	{ "isl1208", TYPE_ISL1208 },
+	{ "isl1218", TYPE_ISL1218 },
+	{ "isl1219", TYPE_ISL1219 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, isl1208_id);
@@ -695,6 +840,7 @@ MODULE_DEVICE_TABLE(i2c, isl1208_id);
 static const struct of_device_id isl1208_of_match[] = {
 	{ .compatible = "isil,isl1208" },
 	{ .compatible = "isil,isl1218" },
+	{ .compatible = "isil,isl1219" },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, isl1208_of_match);