From d6c3029f32f72db7ba7b4183b0423cce2267ca3d Mon Sep 17 00:00:00 2001 From: Uwe Kleine-König Date: Sun, 20 May 2018 15:37:23 +0200 Subject: rtc: pcf2127: add support for accessing internal static RAM MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Signed-off-by: Alexandre Belloni --- drivers/rtc/rtc-pcf2127.c | 68 ++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 62 insertions(+), 6 deletions(-) (limited to 'drivers/rtc/rtc-pcf2127.c') 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 }, { } }; -- cgit v1.2.3-59-g8ed1b