[PATCH v3 2/4] rtc: pcf85363: Add support for NXP pcf85263 rtc

[Biju Das]

Add support for NXP pcf85263 real-time clock. pcf85263 rtc is compatible
with pcf85363,except that pcf85363 has additional 64 bytes of RAM.

1 byte of nvmem is supported and exposed in sysfs (# is the instance
number,starting with 0): /sys/bus/nvmem/devices/pcf85x63-#/nvmem

Signed-off-by: Biju Das <biju....@bp.renesas.com>
---
V1-->V2
        * Incorporated Alexandre and Geert's review comment.
V2-->V3
        * Incorporated Geert's review comment.
---
 drivers/rtc/rtc-pcf85363.c | 87 ++++++++++++++++++++++++++++++++++++----------
 1 file changed, 69 insertions(+), 18 deletions(-)

diff --git a/drivers/rtc/rtc-pcf85363.c b/drivers/rtc/rtc-pcf85363.c
index c04a1ed..6a0a994 100644
--- a/drivers/rtc/rtc-pcf85363.c
+++ b/drivers/rtc/rtc-pcf85363.c
@@ -120,6 +120,11 @@ struct pcf85363 {
        struct regmap           *regmap;
 };
 
+struct pcf85x63_config {
+       struct regmap_config regmap;
+       unsigned int num_nvram;
+};
+
 static int pcf85363_rtc_read_time(struct device *dev, struct rtc_time *tm)
 {
        struct pcf85363 *pcf85363 = dev_get_drvdata(dev);
@@ -311,25 +316,68 @@ static int pcf85363_nvram_write(void *priv, unsigned int 
offset, void *val,
                                 val, bytes);
 }
 
-static const struct regmap_config regmap_config = {
-       .reg_bits = 8,
-       .val_bits = 8,
-       .max_register = 0x7f,
+static int pcf85x63_nvram_read(void *priv, unsigned int offset, void *val,
+                              size_t bytes)
+{
+       struct pcf85363 *pcf85363 = priv;
+
+       return regmap_read(pcf85363->regmap, CTRL_RAMBYTE, val);
+}
+
+static int pcf85x63_nvram_write(void *priv, unsigned int offset, void *val,
+                               size_t bytes)
+{
+       struct pcf85363 *pcf85363 = priv;
+
+       return regmap_write(pcf85363->regmap, CTRL_RAMBYTE,
+                               *((unsigned int *)val));
+}
+
+static const struct pcf85x63_config pcf_85263_config = {
+       {
+               .reg_bits = 8,
+               .val_bits = 8,
+               .max_register = 0x2f,
+       },
+       1
+};
+
+static const struct pcf85x63_config pcf_85363_config = {
+       {
+               .reg_bits = 8,
+               .val_bits = 8,
+               .max_register = 0x7f,
+       },
+       2
 };
 
 static int pcf85363_probe(struct i2c_client *client,
                          const struct i2c_device_id *id)
 {
        struct pcf85363 *pcf85363;
-       struct nvmem_config nvmem_cfg = {
-               .name = "pcf85363-",
-               .word_size = 1,
-               .stride = 1,
-               .size = NVRAM_SIZE,
-               .reg_read = pcf85363_nvram_read,
-               .reg_write = pcf85363_nvram_write,
+       const struct pcf85x63_config *config = &pcf_85363_config;
+       const void *data = of_device_get_match_data(&client->dev);
+       static struct nvmem_config nvmem_cfg[] = {
+               {
+                       .name = "pcf85x63-",
+                       .word_size = 1,
+                       .stride = 1,
+                       .size = 1,
+                       .reg_read = pcf85x63_nvram_read,
+                       .reg_write = pcf85x63_nvram_write,
+               }, {
+                       .name = "pcf85363-",
+                       .word_size = 1,
+                       .stride = 1,
+                       .size = NVRAM_SIZE,
+                       .reg_read = pcf85363_nvram_read,
+                       .reg_write = pcf85363_nvram_write,
+               },
        };
-       int ret;
+       int ret, i;
+
+       if (data)
+               config = data;
 
        if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
                return -ENODEV;
@@ -339,7 +387,7 @@ static int pcf85363_probe(struct i2c_client *client,
        if (!pcf85363)
                return -ENOMEM;
 
-       pcf85363->regmap = devm_regmap_init_i2c(client, &regmap_config);
+       pcf85363->regmap = devm_regmap_init_i2c(client, &config->regmap);
        if (IS_ERR(pcf85363->regmap)) {
                dev_err(&client->dev, "regmap allocation failed\n");
                return PTR_ERR(pcf85363->regmap);
@@ -370,15 +418,18 @@ static int pcf85363_probe(struct i2c_client *client,
 
        ret = rtc_register_device(pcf85363->rtc);
 
-       nvmem_cfg.priv = pcf85363;
-       rtc_nvmem_register(pcf85363->rtc, &nvmem_cfg);
+       for (i = 0; i < config->num_nvram; i++) {
+               nvmem_cfg[i].priv = pcf85363;
+               rtc_nvmem_register(pcf85363->rtc, &nvmem_cfg[i]);
+       }
 
        return ret;
 }
 
 static const struct of_device_id dev_ids[] = {
-       { .compatible = "nxp,pcf85363" },
-       {}
+       { .compatible = "nxp,pcf85263", .data = &pcf_85263_config },
+       { .compatible = "nxp,pcf85363", .data = &pcf_85363_config },
+       { /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, dev_ids);
 
@@ -393,5 +444,5 @@ static struct i2c_driver pcf85363_driver = {
 module_i2c_driver(pcf85363_driver);
 
 MODULE_AUTHOR("Eric Nelson");
-MODULE_DESCRIPTION("pcf85363 I2C RTC driver");
+MODULE_DESCRIPTION("pcf85263/pcf85363 I2C RTC driver");
 MODULE_LICENSE("GPL");
-- 
2.7.4