rtc: ds3232: get SRAM access using NVMEM Framework
DS3232 RTC has 236 bytes of persistent memory.
Add RTC SRAM read and write access using
the NVMEM Framework.
Signed-off-by: Han Nandor <nandor.han@vaisala.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
diff --git a/drivers/rtc/rtc-ds3232.c b/drivers/rtc/rtc-ds3232.c
index 7184e51..1e9312f 100644
--- a/drivers/rtc/rtc-ds3232.c
+++ b/drivers/rtc/rtc-ds3232.c
@@ -48,6 +48,10 @@
# define DS3232_REG_SR_A1F 0x01
#define DS3232_REG_TEMPERATURE 0x11
+#define DS3232_REG_SRAM_START 0x14
+#define DS3232_REG_SRAM_END 0xFF
+
+#define DS3232_REG_SRAM_SIZE 236
struct ds3232 {
struct device *dev;
@@ -461,11 +465,39 @@
.alarm_irq_enable = ds3232_alarm_irq_enable,
};
+static int ds3232_nvmem_read(void *priv, unsigned int offset, void *val,
+ size_t bytes)
+{
+ struct regmap *ds3232_regmap = (struct regmap *)priv;
+
+ return regmap_bulk_read(ds3232_regmap, DS3232_REG_SRAM_START + offset,
+ val, bytes);
+}
+
+static int ds3232_nvmem_write(void *priv, unsigned int offset, void *val,
+ size_t bytes)
+{
+ struct regmap *ds3232_regmap = (struct regmap *)priv;
+
+ return regmap_bulk_write(ds3232_regmap, DS3232_REG_SRAM_START + offset,
+ val, bytes);
+}
+
static int ds3232_probe(struct device *dev, struct regmap *regmap, int irq,
const char *name)
{
struct ds3232 *ds3232;
int ret;
+ struct nvmem_config nvmem_cfg = {
+ .name = "ds3232_sram",
+ .stride = 1,
+ .size = DS3232_REG_SRAM_SIZE,
+ .word_size = 1,
+ .reg_read = ds3232_nvmem_read,
+ .reg_write = ds3232_nvmem_write,
+ .priv = regmap,
+ .type = NVMEM_TYPE_BATTERY_BACKED
+ };
ds3232 = devm_kzalloc(dev, sizeof(*ds3232), GFP_KERNEL);
if (!ds3232)
@@ -490,6 +522,10 @@
if (IS_ERR(ds3232->rtc))
return PTR_ERR(ds3232->rtc);
+ ret = rtc_nvmem_register(ds3232->rtc, &nvmem_cfg);
+ if(ret)
+ return ret;
+
if (ds3232->irq > 0) {
ret = devm_request_threaded_irq(dev, ds3232->irq, NULL,
ds3232_irq,
@@ -542,7 +578,7 @@
static const struct regmap_config config = {
.reg_bits = 8,
.val_bits = 8,
- .max_register = 0x13,
+ .max_register = DS3232_REG_SRAM_END,
};
regmap = devm_regmap_init_i2c(client, &config);
@@ -609,7 +645,7 @@
static const struct regmap_config config = {
.reg_bits = 8,
.val_bits = 8,
- .max_register = 0x13,
+ .max_register = DS3232_REG_SRAM_END,
.write_flag_mask = 0x80,
};
struct regmap *regmap;