[U-Boot] [PATCH v2 2/2] rtc: Add DM support to ds1307

Chris Packham judge.packham at gmail.com
Sat Apr 29 02:50:42 UTC 2017


On Sat, Apr 29, 2017 at 12:27 PM, Simon Glass <sjg at chromium.org> wrote:
> Hi Chris,
>
> On 25 April 2017 at 23:19, Chris Packham <judge.packham at gmail.com> wrote:
>> Add an implementation of the ds1307 driver that uses the driver model
>> i2c APIs.
>>
>> Signed-off-by: Chris Packham <judge.packham at gmail.com>
>>
>> ---
>>
>> Changes in v2: None
>>
>>  drivers/rtc/Kconfig  |   7 ++
>>  drivers/rtc/ds1307.c | 196 ++++++++++++++++++++++++++++++++++++++++++++++-----
>>  2 files changed, 184 insertions(+), 19 deletions(-)
>>
>> diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
>> index cb79a01..d06130c7 100644
>> --- a/drivers/rtc/Kconfig
>> +++ b/drivers/rtc/Kconfig
>> @@ -23,4 +23,11 @@ config RTC_PCF2127
>>           has a selectable I2C-bus or SPI-bus, a backup battery switch-over circuit, a
>>           programmable watchdog function, a timestamp function, and many other features.
>>
>> +config RTC_DS1307
>> +       bool "Enable DS1307 driver"
>> +       depends on DM_RTC
>> +       help
>> +         Support for Dallas Semiconductor (now Maxim) DS1307 and DS1338/9 and
>> +         compatible Real Time Clock devices.
>> +
>>  endmenu
>> diff --git a/drivers/rtc/ds1307.c b/drivers/rtc/ds1307.c
>> index 3be1da6..68d1b65 100644
>> --- a/drivers/rtc/ds1307.c
>> +++ b/drivers/rtc/ds1307.c
>> @@ -16,29 +16,12 @@
>>
>>  #include <common.h>
>>  #include <command.h>
>> +#include <dm.h>
>>  #include <rtc.h>
>>  #include <i2c.h>
>>
>>  #if defined(CONFIG_CMD_DATE)
>
> Can that go in the Makefile?
>

Actually under the DM it probably doesn't make sense for it to go
anywhere. Eventually there should be a depend/select in the KConfig
but I think CONFIG_RTC_DS1307 is sufficient to control the
compilation. I will move it inside the #ifndef to indicate that it
should be dropped when the non-DM support is removed.

>>
>> -/*---------------------------------------------------------------------*/
>> -#undef DEBUG_RTC
>> -
>> -#ifdef DEBUG_RTC
>> -#define DEBUGR(fmt,args...) printf(fmt ,##args)
>> -#else
>> -#define DEBUGR(fmt,args...)
>> -#endif
>> -/*---------------------------------------------------------------------*/
>> -
>> -#ifndef CONFIG_SYS_I2C_RTC_ADDR
>> -# define CONFIG_SYS_I2C_RTC_ADDR       0x68
>> -#endif
>> -
>> -#if defined(CONFIG_RTC_DS1307) && (CONFIG_SYS_I2C_SPEED > 100000)
>> -# error The DS1307 is specified only up to 100kHz!
>> -#endif
>> -
>>  /*
>>   * RTC register addresses
>>   */
>> @@ -62,6 +45,26 @@
>>  #define MCP7941X_BIT_ST                0x80
>>  #define MCP7941X_BIT_VBATEN    0x08
>>
>> +#ifndef CONFIG_DM_RTC
>> +
>> +/*---------------------------------------------------------------------*/
>> +#undef DEBUG_RTC
>> +
>> +#ifdef DEBUG_RTC
>> +#define DEBUGR(fmt, args...) printf(fmt, ##args)
>> +#else
>> +#define DEBUGR(fmt, args...)
>> +#endif
>> +/*---------------------------------------------------------------------*/
>> +
>> +#ifndef CONFIG_SYS_I2C_RTC_ADDR
>> +# define CONFIG_SYS_I2C_RTC_ADDR       0x68
>> +#endif
>> +
>> +#if defined(CONFIG_RTC_DS1307) && (CONFIG_SYS_I2C_SPEED > 100000)
>> +# error The DS1307 is specified only up to 100kHz!
>> +#endif
>> +
>>  static uchar rtc_read (uchar reg);
>>  static void rtc_write (uchar reg, uchar val);
>>
>> @@ -211,4 +214,159 @@ static void rtc_write (uchar reg, uchar val)
>>  {
>>         i2c_reg_write (CONFIG_SYS_I2C_RTC_ADDR, reg, val);
>>  }
>> -#endif
>> +
>> +#else
>> +static int ds1307_rtc_set(struct udevice *dev, const struct rtc_time *tm)
>> +{
>> +       int ret;
>> +       uchar buf[7];
>> +
>> +       debug("Set DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
>> +             tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_wday,
>> +             tm->tm_hour, tm->tm_min, tm->tm_sec);
>> +
>> +       if (tm->tm_year < 1970 || tm->tm_year > 2069)
>> +               printf("WARNING: year should be between 1970 and 2069!\n");
>> +
>> +       buf[RTC_YR_REG_ADDR] = bin2bcd(tm->tm_year % 100);
>> +       buf[RTC_MON_REG_ADDR] = bin2bcd(tm->tm_mon);
>> +       buf[RTC_DAY_REG_ADDR] = bin2bcd(tm->tm_wday + 1);
>> +       buf[RTC_DATE_REG_ADDR] = bin2bcd(tm->tm_mday);
>> +       buf[RTC_HR_REG_ADDR] = bin2bcd(tm->tm_hour);
>> +       buf[RTC_MIN_REG_ADDR] = bin2bcd(tm->tm_min);
>> +       buf[RTC_SEC_REG_ADDR] = bin2bcd(tm->tm_sec);
>> +
>> +       if (of_device_is_compatible(dev, "microchip,mcp7941x")) {
>
> Can you please use the data field in your compatible ID list instead
> of checking this here?
>

Will do in the next version.

>> +               buf[RTC_DAY_REG_ADDR] |= MCP7941X_BIT_VBATEN;
>> +               buf[RTC_SEC_REG_ADDR] |= MCP7941X_BIT_ST;
>> +       }
>> +
>> +       ret = dm_i2c_write(dev, 0, buf, sizeof(buf));
>> +       if (ret < 0)
>> +               return ret;
>> +
>> +       return 0;
>> +}
>> +
>> +static int ds1307_rtc_get(struct udevice *dev, struct rtc_time *tm)
>> +{
>> +       int ret;
>> +       uchar buf[7];
>> +
>> +read_rtc:
>> +       ret = dm_i2c_read(dev, 0, buf, sizeof(buf));
>> +       if (ret < 0)
>> +               return ret;
>> +
>> +       if (of_device_is_compatible(dev, "dallas,ds1307")) {
>
> Same with this
>
>> +               if (buf[RTC_SEC_REG_ADDR] & RTC_SEC_BIT_CH) {
>> +                       printf("### Warning: RTC oscillator has stopped\n");
>> +                       /* clear the CH flag */
>> +                       buf[RTC_SEC_REG_ADDR] &= ~RTC_SEC_BIT_CH;
>> +                       dm_i2c_reg_write(dev, RTC_SEC_REG_ADDR,
>> +                                        buf[RTC_SEC_REG_ADDR]);
>> +                       return -1;
>> +               }
>> +       }
>> +
>> +       if (of_device_is_compatible(dev, "dallas,mcp7941x")) {
>> +               /* make sure that the backup battery is enabled */
>> +               if (!(buf[RTC_DAY_REG_ADDR] & MCP7941X_BIT_VBATEN)) {
>> +                       dm_i2c_reg_write(dev, RTC_DAY_REG_ADDR,
>> +                                        buf[RTC_DAY_REG_ADDR] |
>> +                                        MCP7941X_BIT_VBATEN);
>> +               }
>> +
>> +               /* clock halted?  turn it on, so clock can tick. */
>> +               if (!(buf[RTC_SEC_REG_ADDR] & MCP7941X_BIT_ST)) {
>> +                       dm_i2c_reg_write(dev, RTC_SEC_REG_ADDR,
>> +                                        MCP7941X_BIT_ST);
>> +                       printf("Started RTC\n");
>> +                       goto read_rtc;
>> +               }
>> +       }
>> +
>> +       tm->tm_sec  = bcd2bin(buf[RTC_SEC_REG_ADDR] & 0x7F);
>> +       tm->tm_min  = bcd2bin(buf[RTC_MIN_REG_ADDR] & 0x7F);
>> +       tm->tm_hour = bcd2bin(buf[RTC_HR_REG_ADDR] & 0x3F);
>> +       tm->tm_mday = bcd2bin(buf[RTC_DATE_REG_ADDR] & 0x3F);
>> +       tm->tm_mon  = bcd2bin(buf[RTC_MON_REG_ADDR] & 0x1F);
>> +       tm->tm_year = bcd2bin(buf[RTC_YR_REG_ADDR]) +
>> +                             (bcd2bin(buf[RTC_YR_REG_ADDR]) >= 70 ?
>> +                              1900 : 2000);
>> +       tm->tm_wday = bcd2bin((buf[RTC_DAY_REG_ADDR] - 1) & 0x07);
>> +       tm->tm_yday = 0;
>> +       tm->tm_isdst = 0;
>> +
>> +       debug("Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
>> +             tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_wday,
>> +             tm->tm_hour, tm->tm_min, tm->tm_sec);
>> +
>> +       return 0;
>> +}
>> +
>> +static int ds1307_rtc_reset(struct udevice *dev)
>> +{
>> +       int ret;
>> +       struct rtc_time tmp = {
>> +               .tm_year = 1970,
>> +               .tm_mon = 1,
>> +               .tm_mday = 1,
>> +               .tm_hour = 0,
>> +               .tm_min = 0,
>> +               .tm_sec = 0,
>> +       };
>> +
>> +       /* clear Clock Halt */
>> +       ret = dm_i2c_reg_write(dev, RTC_SEC_REG_ADDR, 0x00);
>> +       if (ret < 0)
>> +               return ret;
>> +       ret = dm_i2c_reg_write(dev, RTC_CTL_REG_ADDR,
>> +                              RTC_CTL_BIT_SQWE | RTC_CTL_BIT_RS1 |
>> +                              RTC_CTL_BIT_RS0);
>> +       if (ret < 0)
>> +               return ret;
>> +
>> +       ret = ds1307_rtc_set(dev, &tmp);
>> +       if (ret < 0)
>> +               return ret;
>> +
>> +       debug("RTC:   %4d-%02d-%02d %2d:%02d:%02d UTC\n",
>> +             tmp.tm_year, tmp.tm_mon, tmp.tm_mday,
>> +             tmp.tm_hour, tmp.tm_min, tmp.tm_sec);
>> +
>> +       return 0;
>> +}
>> +
>> +static int ds1307_probe(struct udevice *dev)
>> +{
>> +       i2c_set_chip_flags(dev, DM_I2C_CHIP_RD_ADDRESS |
>> +                          DM_I2C_CHIP_WR_ADDRESS);
>> +
>> +       return 0;
>> +}
>> +
>> +static const struct rtc_ops ds1307_rtc_ops = {
>> +       .get = ds1307_rtc_get,
>> +       .set = ds1307_rtc_set,
>> +       .reset = ds1307_rtc_reset,
>> +};
>> +
>> +static const struct udevice_id ds1307_rtc_ids[] = {
>> +       { .compatible = "dallas,ds1307" },
>> +       { .compatible = "dallas,ds1337" },
>> +       { .compatible = "dallas,ds1340" },
>> +       { .compatible = "microchip,mcp7941x" },
>
> Here you can add a .data field to each, using an enum for the
> different values, and save it in some private data. See ns16550.c for
> an example.
>

Thanks for the pointer. I'll do that.

>> +       { }
>> +};
>> +
>> +U_BOOT_DRIVER(rtc_ds1307) = {
>> +       .name   = "rtc-ds1307",
>> +       .id     = UCLASS_RTC,
>> +       .probe  = ds1307_probe,
>> +       .of_match = ds1307_rtc_ids,
>> +       .ops    = &ds1307_rtc_ops,
>> +};
>> +#endif /* CONFIG_DM_RTC */
>> +
>> +#endif /* CONFIG_CMD_DATE*/
>> --
>> 2.10.1
>>
>
> Regards,
> Simon


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