[PATCH] rtc: add support of nvram for maxim dallas rtc ds1343

From: Raghavendra Ganiga
Date: Mon Jun 09 2014 - 13:30:15 EST


This is a patch to add support of nvram for maxim dallas
rtc ds1343

Signed-off-by: Raghavendra Chandra Ganiga <ravi23ganiga@xxxxxxxxx>
---
drivers/rtc/rtc-ds1343.c | 75 ++++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 73 insertions(+), 2 deletions(-)

diff --git a/drivers/rtc/rtc-ds1343.c b/drivers/rtc/rtc-ds1343.c
index c371918..ae9f997 100644
--- a/drivers/rtc/rtc-ds1343.c
+++ b/drivers/rtc/rtc-ds1343.c
@@ -4,6 +4,7 @@
* Real Time Clock
*
* Author : Raghavendra Chandra Ganiga <ravi23ganiga@xxxxxxxxx>
+ * Ankur Srivastava <sankurece@xxxxxxxxx> : DS1343 Nvram Support
*
* 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
@@ -45,6 +46,9 @@
#define DS1343_CONTROL_REG 0x0F
#define DS1343_STATUS_REG 0x10
#define DS1343_TRICKLE_REG 0x11
+#define DS1343_NVRAM 0x20
+
+#define DS1343_NVRAM_LEN 96

/* DS1343 Control Registers bits */
#define DS1343_EOSC 0x80
@@ -149,6 +153,64 @@ static ssize_t ds1343_store_glitchfilter(struct device *dev,
static DEVICE_ATTR(glitch_filter, S_IRUGO | S_IWUSR, ds1343_show_glitchfilter,
ds1343_store_glitchfilter);

+static ssize_t ds1343_nvram_write(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *attr,
+ char *buf, loff_t off, size_t count)
+{
+ int ret;
+ unsigned char address;
+ struct device *dev = kobj_to_dev(kobj);
+ struct ds1343_priv *priv = dev_get_drvdata(dev);
+
+ if (unlikely(!count))
+ return count;
+
+ if ((count + off) > DS1343_NVRAM_LEN)
+ count = DS1343_NVRAM_LEN - off;
+
+ address = DS1343_NVRAM + off;
+
+ ret = regmap_bulk_write(priv->map, address, buf, count);
+ if (ret < 0)
+ dev_err(&priv->spi->dev, "Error in nvram write %d", ret);
+
+ return (ret < 0) ? ret : count;
+}
+
+
+static ssize_t ds1343_nvram_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *attr,
+ char *buf, loff_t off, size_t count)
+{
+ int ret;
+ unsigned char address;
+ struct device *dev = kobj_to_dev(kobj);
+ struct ds1343_priv *priv = dev_get_drvdata(dev);
+
+ if (unlikely(!count))
+ return count;
+
+ if ((count + off) > DS1343_NVRAM_LEN)
+ count = DS1343_NVRAM_LEN - off;
+
+ address = DS1343_NVRAM + off;
+
+ ret = regmap_bulk_read(priv->map, address, buf, count);
+ if (ret < 0)
+ dev_err(&priv->spi->dev, "Error in nvram read %d\n", ret);
+
+ return (ret < 0) ? ret : count;
+}
+
+
+static struct bin_attribute nvram_attr = {
+ .attr.name = "nvram",
+ .attr.mode = S_IRUGO | S_IWUSR,
+ .read = ds1343_nvram_read,
+ .write = ds1343_nvram_write,
+ .size = DS1343_NVRAM_LEN,
+};
+
static ssize_t ds1343_show_alarmstatus(struct device *dev,
struct device_attribute *attr, char *buf)
{
@@ -274,12 +336,16 @@ static int ds1343_sysfs_register(struct device *dev)
if (err)
goto error1;

+ err = device_create_bin_file(dev, &nvram_attr);
+ if (err)
+ goto error2;
+
if (priv->irq <= 0)
return err;

err = device_create_file(dev, &dev_attr_alarm_mode);
if (err)
- goto error2;
+ goto error3;

err = device_create_file(dev, &dev_attr_alarm_status);
if (!err)
@@ -287,6 +353,9 @@ static int ds1343_sysfs_register(struct device *dev)

device_remove_file(dev, &dev_attr_alarm_mode);

+error3:
+ device_remove_bin_file(dev, &nvram_attr);
+
error2:
device_remove_file(dev, &dev_attr_trickle_charger);

@@ -302,6 +371,7 @@ static void ds1343_sysfs_unregister(struct device *dev)

device_remove_file(dev, &dev_attr_glitch_filter);
device_remove_file(dev, &dev_attr_trickle_charger);
+ device_remove_bin_file(dev, &nvram_attr);

if (priv->irq <= 0)
return;
@@ -684,6 +754,7 @@ static struct spi_driver ds1343_driver = {
module_spi_driver(ds1343_driver);

MODULE_DESCRIPTION("DS1343 RTC SPI Driver");
-MODULE_AUTHOR("Raghavendra Chandra Ganiga <ravi23ganiga@xxxxxxxxx>");
+MODULE_AUTHOR("Raghavendra Chandra Ganiga <ravi23ganiga@xxxxxxxxx>,"
+ "Ankur Srivastava <sankurece@xxxxxxxxx>");
MODULE_LICENSE("GPL v2");
MODULE_VERSION(DS1343_DRV_VERSION);
--
1.9.1

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