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authorUwe Kleine-König <u.kleine-koenig@pengutronix.de>2018-05-20 15:37:23 +0200
committerAlexandre Belloni <alexandre.belloni@bootlin.com>2018-07-11 20:41:22 +0200
commitd6c3029f32f72db7ba7b4183b0423cce2267ca3d (patch)
treef5d0bea6e73a4a4de1a4292a3c1f07806489f711 /drivers/rtc
parentcd7f3a249dbed2858e6c2f30e5be7f1f7a709ee2 (diff)
downloadlinux-d6c3029f32f72db7ba7b4183b0423cce2267ca3d.tar.bz2
rtc: pcf2127: add support for accessing internal static RAM
The PCF2127 has 512 bytes of internal static RAM and this patch expands the driver to access this memory. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Diffstat (limited to 'drivers/rtc')
-rw-r--r--drivers/rtc/rtc-pcf2127.c68
1 files changed, 62 insertions, 6 deletions
diff --git a/drivers/rtc/rtc-pcf2127.c b/drivers/rtc/rtc-pcf2127.c
index e83be1852c2f..9f99a0966550 100644
--- a/drivers/rtc/rtc-pcf2127.c
+++ b/drivers/rtc/rtc-pcf2127.c
@@ -36,6 +36,11 @@
#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 {
@@ -183,10 +188,47 @@ static const struct rtc_class_ops pcf2127_rtc_ops = {
.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)
+ const char *name, bool has_nvmem)
{
struct pcf2127 *pcf2127;
+ int ret = 0;
dev_dbg(dev, "%s\n", __func__);
@@ -200,8 +242,21 @@ static int pcf2127_probe(struct device *dev, struct regmap *regmap,
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 PTR_ERR_OR_ZERO(pcf2127->rtc);
+ return ret;
}
#ifdef CONFIG_OF
@@ -309,11 +364,11 @@ static int pcf2127_i2c_probe(struct i2c_client *client,
}
return pcf2127_probe(&client->dev, regmap,
- pcf2127_i2c_driver.driver.name);
+ pcf2127_i2c_driver.driver.name, id->driver_data);
}
static const struct i2c_device_id pcf2127_i2c_id[] = {
- { "pcf2127", 0 },
+ { "pcf2127", 1 },
{ "pcf2129", 0 },
{ }
};
@@ -372,11 +427,12 @@ static int pcf2127_spi_probe(struct spi_device *spi)
return PTR_ERR(regmap);
}
- return pcf2127_probe(&spi->dev, regmap, pcf2127_spi_driver.driver.name);
+ 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", 0 },
+ { "pcf2127", 1 },
{ "pcf2129", 0 },
{ }
};