[PATCH 16/16] rtc: rv3029: add nvram support

From: Alexandre Belloni
Date: Sat Dec 14 2019 - 17:10:44 EST


Export the 8 byte RAM using nvmem.

Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
---
drivers/rtc/rtc-rv3029c2.c | 36 +++++++++++++++++++++++++++++++-----
1 file changed, 31 insertions(+), 5 deletions(-)

diff --git a/drivers/rtc/rtc-rv3029c2.c b/drivers/rtc/rtc-rv3029c2.c
index 5610ff562652..4eda0db72b66 100644
--- a/drivers/rtc/rtc-rv3029c2.c
+++ b/drivers/rtc/rtc-rv3029c2.c
@@ -109,10 +109,8 @@
#define RV3029_CONTROL_E2P_TOV_MASK 0x3F /* XTAL turnover temp mask */

/* user ram section */
-#define RV3029_USR1_RAM_PAGE 0x38
-#define RV3029_USR1_SECTION_LEN 0x04
-#define RV3029_USR2_RAM_PAGE 0x3C
-#define RV3029_USR2_SECTION_LEN 0x04
+#define RV3029_RAM_PAGE 0x38
+#define RV3029_RAM_SECTION_LEN 8

struct rv3029_data {
struct device *dev;
@@ -474,6 +472,18 @@ static int rv3029_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
}
}

+static int rv3029_nvram_write(void *priv, unsigned int offset, void *val,
+ size_t bytes)
+{
+ return regmap_bulk_write(priv, RV3029_RAM_PAGE + offset, val, bytes);
+}
+
+static int rv3029_nvram_read(void *priv, unsigned int offset, void *val,
+ size_t bytes)
+{
+ return regmap_bulk_read(priv, RV3029_RAM_PAGE + offset, val, bytes);
+}
+
static const struct rv3029_trickle_tab_elem {
u32 r; /* resistance in ohms */
u8 conf; /* trickle config bits */
@@ -694,6 +704,15 @@ static int rv3029_probe(struct device *dev, struct regmap *regmap, int irq,
const char *name)
{
struct rv3029_data *rv3029;
+ struct nvmem_config nvmem_cfg = {
+ .name = "rv3029_nvram",
+ .word_size = 1,
+ .stride = 1,
+ .size = RV3029_RAM_SECTION_LEN,
+ .type = NVMEM_TYPE_BATTERY_BACKED,
+ .reg_read = rv3029_nvram_read,
+ .reg_write = rv3029_nvram_write,
+ };
int rc = 0;

rv3029 = devm_kzalloc(dev, sizeof(*rv3029), GFP_KERNEL);
@@ -731,7 +750,14 @@ static int rv3029_probe(struct device *dev, struct regmap *regmap, int irq,
rv3029->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
rv3029->rtc->range_max = RTC_TIMESTAMP_END_2079;

- return rtc_register_device(rv3029->rtc);
+ rc = rtc_register_device(rv3029->rtc);
+ if (rc)
+ return rc;
+
+ nvmem_cfg.priv = rv3029->regmap;
+ rtc_nvmem_register(rv3029->rtc, &nvmem_cfg);
+
+ return 0;
}

static const struct regmap_range rv3029_holes_range[] = {
--
2.23.0