Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 497 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-pcf2127.c b/drivers/rtc/rtc-pcf2127.c
new file mode 100644
index 000000000..8c62406f9
--- /dev/null
+++ b/drivers/rtc/rtc-pcf2127.c
@@ -0,0 +1,497 @@
+/*
+ * An I2C and SPI driver for the NXP PCF2127/29 RTC
+ * Copyright 2013 Til-Technologies
+ *
+ * Author: Renaud Cerrato <r.cerrato@til-technologies.fr>
+ *
+ * based on the other drivers in this same directory.
+ *
+ * Datasheet: http://cache.nxp.com/documents/data_sheet/PCF2127.pdf
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/i2c.h>
+#include <linux/spi/spi.h>
+#include <linux/bcd.h>
+#include <linux/rtc.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+
+#define PCF2127_REG_CTRL1       (0x00)  /* Control Register 1 */
+#define PCF2127_REG_CTRL2       (0x01)  /* Control Register 2 */
+
+#define PCF2127_REG_CTRL3       (0x02)  /* Control Register 3 */
+#define PCF2127_REG_CTRL3_BLF		BIT(2)
+
+#define PCF2127_REG_SC          (0x03)  /* datetime */
+#define PCF2127_REG_MN          (0x04)
+#define PCF2127_REG_HR          (0x05)
+#define PCF2127_REG_DM          (0x06)
+#define PCF2127_REG_DW          (0x07)
+#define PCF2127_REG_MO          (0x08)
+#define PCF2127_REG_YR          (0x09)
+
+/* the pcf2127 has 512 bytes nvmem, pcf2129 doesn't */
+#define PCF2127_REG_RAM_addr_MSB       0x1a
+#define PCF2127_REG_RAM_wrt_cmd        0x1c
+#define PCF2127_REG_RAM_rd_cmd         0x1d
+
+#define PCF2127_OSF             BIT(7)  /* Oscillator Fail flag */
+
+struct pcf2127 {
+	struct rtc_device *rtc;
+	struct regmap *regmap;
+};
+
+/*
+ * In the routines that deal directly with the pcf2127 hardware, we use
+ * rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch.
+ */
+static int pcf2127_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	struct pcf2127 *pcf2127 = dev_get_drvdata(dev);
+	unsigned char buf[10];
+	int ret;
+
+	/*
+	 * Avoid reading CTRL2 register as it causes WD_VAL register
+	 * value to reset to 0 which means watchdog is stopped.
+	 */
+	ret = regmap_bulk_read(pcf2127->regmap, PCF2127_REG_CTRL3,
+			       (buf + PCF2127_REG_CTRL3),
+			       ARRAY_SIZE(buf) - PCF2127_REG_CTRL3);
+	if (ret) {
+		dev_err(dev, "%s: read error\n", __func__);
+		return ret;
+	}
+
+	if (buf[PCF2127_REG_CTRL3] & PCF2127_REG_CTRL3_BLF)
+		dev_info(dev,
+			"low voltage detected, check/replace RTC battery.\n");
+
+	if (buf[PCF2127_REG_SC] & PCF2127_OSF) {
+		/*
+		 * no need clear the flag here,
+		 * it will be cleared once the new date is saved
+		 */
+		dev_warn(dev,
+			 "oscillator stop detected, date/time is not reliable\n");
+		return -EINVAL;
+	}
+
+	dev_dbg(dev,
+		"%s: raw data is cr3=%02x, sec=%02x, min=%02x, hr=%02x, "
+		"mday=%02x, wday=%02x, mon=%02x, year=%02x\n",
+		__func__, buf[PCF2127_REG_CTRL3], buf[PCF2127_REG_SC],
+		buf[PCF2127_REG_MN], buf[PCF2127_REG_HR],
+		buf[PCF2127_REG_DM], buf[PCF2127_REG_DW],
+		buf[PCF2127_REG_MO], buf[PCF2127_REG_YR]);
+
+	tm->tm_sec = bcd2bin(buf[PCF2127_REG_SC] & 0x7F);
+	tm->tm_min = bcd2bin(buf[PCF2127_REG_MN] & 0x7F);
+	tm->tm_hour = bcd2bin(buf[PCF2127_REG_HR] & 0x3F); /* rtc hr 0-23 */
+	tm->tm_mday = bcd2bin(buf[PCF2127_REG_DM] & 0x3F);
+	tm->tm_wday = buf[PCF2127_REG_DW] & 0x07;
+	tm->tm_mon = bcd2bin(buf[PCF2127_REG_MO] & 0x1F) - 1; /* rtc mn 1-12 */
+	tm->tm_year = bcd2bin(buf[PCF2127_REG_YR]);
+	if (tm->tm_year < 70)
+		tm->tm_year += 100;	/* assume we are in 1970...2069 */
+
+	dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
+		"mday=%d, mon=%d, year=%d, wday=%d\n",
+		__func__,
+		tm->tm_sec, tm->tm_min, tm->tm_hour,
+		tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
+
+	return 0;
+}
+
+static int pcf2127_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	struct pcf2127 *pcf2127 = dev_get_drvdata(dev);
+	unsigned char buf[7];
+	int i = 0, err;
+
+	dev_dbg(dev, "%s: secs=%d, mins=%d, hours=%d, "
+		"mday=%d, mon=%d, year=%d, wday=%d\n",
+		__func__,
+		tm->tm_sec, tm->tm_min, tm->tm_hour,
+		tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
+
+	/* hours, minutes and seconds */
+	buf[i++] = bin2bcd(tm->tm_sec);	/* this will also clear OSF flag */
+	buf[i++] = bin2bcd(tm->tm_min);
+	buf[i++] = bin2bcd(tm->tm_hour);
+	buf[i++] = bin2bcd(tm->tm_mday);
+	buf[i++] = tm->tm_wday & 0x07;
+
+	/* month, 1 - 12 */
+	buf[i++] = bin2bcd(tm->tm_mon + 1);
+
+	/* year */
+	buf[i++] = bin2bcd(tm->tm_year % 100);
+
+	/* write register's data */
+	err = regmap_bulk_write(pcf2127->regmap, PCF2127_REG_SC, buf, i);
+	if (err) {
+		dev_err(dev,
+			"%s: err=%d", __func__, err);
+		return err;
+	}
+
+	return 0;
+}
+
+#ifdef CONFIG_RTC_INTF_DEV
+static int pcf2127_rtc_ioctl(struct device *dev,
+				unsigned int cmd, unsigned long arg)
+{
+	struct pcf2127 *pcf2127 = dev_get_drvdata(dev);
+	int touser;
+	int ret;
+
+	switch (cmd) {
+	case RTC_VL_READ:
+		ret = regmap_read(pcf2127->regmap, PCF2127_REG_CTRL3, &touser);
+		if (ret)
+			return ret;
+
+		touser = touser & PCF2127_REG_CTRL3_BLF ? 1 : 0;
+
+		if (copy_to_user((void __user *)arg, &touser, sizeof(int)))
+			return -EFAULT;
+		return 0;
+	default:
+		return -ENOIOCTLCMD;
+	}
+}
+#else
+#define pcf2127_rtc_ioctl NULL
+#endif
+
+static const struct rtc_class_ops pcf2127_rtc_ops = {
+	.ioctl		= pcf2127_rtc_ioctl,
+	.read_time	= pcf2127_rtc_read_time,
+	.set_time	= pcf2127_rtc_set_time,
+};
+
+static int pcf2127_nvmem_read(void *priv, unsigned int offset,
+			      void *val, size_t bytes)
+{
+	struct pcf2127 *pcf2127 = priv;
+	int ret;
+	unsigned char offsetbuf[] = { offset >> 8, offset };
+
+	ret = regmap_bulk_write(pcf2127->regmap, PCF2127_REG_RAM_addr_MSB,
+				offsetbuf, 2);
+	if (ret)
+		return ret;
+
+	ret = regmap_bulk_read(pcf2127->regmap, PCF2127_REG_RAM_rd_cmd,
+			       val, bytes);
+
+	return ret ?: bytes;
+}
+
+static int pcf2127_nvmem_write(void *priv, unsigned int offset,
+			       void *val, size_t bytes)
+{
+	struct pcf2127 *pcf2127 = priv;
+	int ret;
+	unsigned char offsetbuf[] = { offset >> 8, offset };
+
+	ret = regmap_bulk_write(pcf2127->regmap, PCF2127_REG_RAM_addr_MSB,
+				offsetbuf, 2);
+	if (ret)
+		return ret;
+
+	ret = regmap_bulk_write(pcf2127->regmap, PCF2127_REG_RAM_wrt_cmd,
+				val, bytes);
+
+	return ret ?: bytes;
+}
+
+static int pcf2127_probe(struct device *dev, struct regmap *regmap,
+			const char *name, bool has_nvmem)
+{
+	struct pcf2127 *pcf2127;
+	int ret = 0;
+
+	dev_dbg(dev, "%s\n", __func__);
+
+	pcf2127 = devm_kzalloc(dev, sizeof(*pcf2127), GFP_KERNEL);
+	if (!pcf2127)
+		return -ENOMEM;
+
+	pcf2127->regmap = regmap;
+
+	dev_set_drvdata(dev, pcf2127);
+
+	pcf2127->rtc = devm_rtc_device_register(dev, name, &pcf2127_rtc_ops,
+						THIS_MODULE);
+	if (IS_ERR(pcf2127->rtc))
+		return PTR_ERR(pcf2127->rtc);
+
+	if (has_nvmem) {
+		struct nvmem_config nvmem_cfg = {
+			.priv = pcf2127,
+			.reg_read = pcf2127_nvmem_read,
+			.reg_write = pcf2127_nvmem_write,
+			.size = 512,
+		};
+
+		ret = rtc_nvmem_register(pcf2127->rtc, &nvmem_cfg);
+	}
+
+	return ret;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id pcf2127_of_match[] = {
+	{ .compatible = "nxp,pcf2127" },
+	{ .compatible = "nxp,pcf2129" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, pcf2127_of_match);
+#endif
+
+#if IS_ENABLED(CONFIG_I2C)
+
+static int pcf2127_i2c_write(void *context, const void *data, size_t count)
+{
+	struct device *dev = context;
+	struct i2c_client *client = to_i2c_client(dev);
+	int ret;
+
+	ret = i2c_master_send(client, data, count);
+	if (ret != count)
+		return ret < 0 ? ret : -EIO;
+
+	return 0;
+}
+
+static int pcf2127_i2c_gather_write(void *context,
+				const void *reg, size_t reg_size,
+				const void *val, size_t val_size)
+{
+	struct device *dev = context;
+	struct i2c_client *client = to_i2c_client(dev);
+	int ret;
+	void *buf;
+
+	if (WARN_ON(reg_size != 1))
+		return -EINVAL;
+
+	buf = kmalloc(val_size + 1, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	memcpy(buf, reg, 1);
+	memcpy(buf + 1, val, val_size);
+
+	ret = i2c_master_send(client, buf, val_size + 1);
+
+	kfree(buf);
+
+	if (ret != val_size + 1)
+		return ret < 0 ? ret : -EIO;
+
+	return 0;
+}
+
+static int pcf2127_i2c_read(void *context, const void *reg, size_t reg_size,
+				void *val, size_t val_size)
+{
+	struct device *dev = context;
+	struct i2c_client *client = to_i2c_client(dev);
+	int ret;
+
+	if (WARN_ON(reg_size != 1))
+		return -EINVAL;
+
+	ret = i2c_master_send(client, reg, 1);
+	if (ret != 1)
+		return ret < 0 ? ret : -EIO;
+
+	ret = i2c_master_recv(client, val, val_size);
+	if (ret != val_size)
+		return ret < 0 ? ret : -EIO;
+
+	return 0;
+}
+
+/*
+ * The reason we need this custom regmap_bus instead of using regmap_init_i2c()
+ * is that the STOP condition is required between set register address and
+ * read register data when reading from registers.
+ */
+static const struct regmap_bus pcf2127_i2c_regmap = {
+	.write = pcf2127_i2c_write,
+	.gather_write = pcf2127_i2c_gather_write,
+	.read = pcf2127_i2c_read,
+};
+
+static struct i2c_driver pcf2127_i2c_driver;
+
+static int pcf2127_i2c_probe(struct i2c_client *client,
+				const struct i2c_device_id *id)
+{
+	struct regmap *regmap;
+	static const struct regmap_config config = {
+		.reg_bits = 8,
+		.val_bits = 8,
+	};
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
+		return -ENODEV;
+
+	regmap = devm_regmap_init(&client->dev, &pcf2127_i2c_regmap,
+					&client->dev, &config);
+	if (IS_ERR(regmap)) {
+		dev_err(&client->dev, "%s: regmap allocation failed: %ld\n",
+			__func__, PTR_ERR(regmap));
+		return PTR_ERR(regmap);
+	}
+
+	return pcf2127_probe(&client->dev, regmap,
+			     pcf2127_i2c_driver.driver.name, id->driver_data);
+}
+
+static const struct i2c_device_id pcf2127_i2c_id[] = {
+	{ "pcf2127", 1 },
+	{ "pcf2129", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, pcf2127_i2c_id);
+
+static struct i2c_driver pcf2127_i2c_driver = {
+	.driver		= {
+		.name	= "rtc-pcf2127-i2c",
+		.of_match_table = of_match_ptr(pcf2127_of_match),
+	},
+	.probe		= pcf2127_i2c_probe,
+	.id_table	= pcf2127_i2c_id,
+};
+
+static int pcf2127_i2c_register_driver(void)
+{
+	return i2c_add_driver(&pcf2127_i2c_driver);
+}
+
+static void pcf2127_i2c_unregister_driver(void)
+{
+	i2c_del_driver(&pcf2127_i2c_driver);
+}
+
+#else
+
+static int pcf2127_i2c_register_driver(void)
+{
+	return 0;
+}
+
+static void pcf2127_i2c_unregister_driver(void)
+{
+}
+
+#endif
+
+#if IS_ENABLED(CONFIG_SPI_MASTER)
+
+static struct spi_driver pcf2127_spi_driver;
+
+static int pcf2127_spi_probe(struct spi_device *spi)
+{
+	static const struct regmap_config config = {
+		.reg_bits = 8,
+		.val_bits = 8,
+		.read_flag_mask = 0xa0,
+		.write_flag_mask = 0x20,
+	};
+	struct regmap *regmap;
+
+	regmap = devm_regmap_init_spi(spi, &config);
+	if (IS_ERR(regmap)) {
+		dev_err(&spi->dev, "%s: regmap allocation failed: %ld\n",
+			__func__, PTR_ERR(regmap));
+		return PTR_ERR(regmap);
+	}
+
+	return pcf2127_probe(&spi->dev, regmap, pcf2127_spi_driver.driver.name,
+			     spi_get_device_id(spi)->driver_data);
+}
+
+static const struct spi_device_id pcf2127_spi_id[] = {
+	{ "pcf2127", 1 },
+	{ "pcf2129", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(spi, pcf2127_spi_id);
+
+static struct spi_driver pcf2127_spi_driver = {
+	.driver		= {
+		.name	= "rtc-pcf2127-spi",
+		.of_match_table = of_match_ptr(pcf2127_of_match),
+	},
+	.probe		= pcf2127_spi_probe,
+	.id_table	= pcf2127_spi_id,
+};
+
+static int pcf2127_spi_register_driver(void)
+{
+	return spi_register_driver(&pcf2127_spi_driver);
+}
+
+static void pcf2127_spi_unregister_driver(void)
+{
+	spi_unregister_driver(&pcf2127_spi_driver);
+}
+
+#else
+
+static int pcf2127_spi_register_driver(void)
+{
+	return 0;
+}
+
+static void pcf2127_spi_unregister_driver(void)
+{
+}
+
+#endif
+
+static int __init pcf2127_init(void)
+{
+	int ret;
+
+	ret = pcf2127_i2c_register_driver();
+	if (ret) {
+		pr_err("Failed to register pcf2127 i2c driver: %d\n", ret);
+		return ret;
+	}
+
+	ret = pcf2127_spi_register_driver();
+	if (ret) {
+		pr_err("Failed to register pcf2127 spi driver: %d\n", ret);
+		pcf2127_i2c_unregister_driver();
+	}
+
+	return ret;
+}
+module_init(pcf2127_init)
+
+static void __exit pcf2127_exit(void)
+{
+	pcf2127_spi_unregister_driver();
+	pcf2127_i2c_unregister_driver();
+}
+module_exit(pcf2127_exit)
+
+MODULE_AUTHOR("Renaud Cerrato <r.cerrato@til-technologies.fr>");
+MODULE_DESCRIPTION("NXP PCF2127/29 RTC driver");
+MODULE_LICENSE("GPL v2");