u-boot/drivers/rtc/ds1306.c
Jean-Christophe PLAGNIOL-VILLARD d1e2319414 rtc: allow rtc_set to return an error and use it in cmd_date
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
2008-09-07 00:56:36 +02:00

477 lines
14 KiB
C

/*
* (C) Copyright 2002 SIXNET, dge@sixnetio.com.
*
* (C) Copyright 2004, Li-Pro.Net <www.li-pro.net>
* Stephan Linz <linz@li-pro.net>
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
/*
* Date & Time support for DS1306 RTC using SPI:
*
* - SXNI855T: it uses its own soft SPI here in this file
* - all other: use the external spi_xfer() function
* (see include/spi.h)
*/
#include <common.h>
#include <command.h>
#include <rtc.h>
#include <spi.h>
#if defined(CONFIG_CMD_DATE)
#define RTC_SECONDS 0x00
#define RTC_MINUTES 0x01
#define RTC_HOURS 0x02
#define RTC_DAY_OF_WEEK 0x03
#define RTC_DATE_OF_MONTH 0x04
#define RTC_MONTH 0x05
#define RTC_YEAR 0x06
#define RTC_SECONDS_ALARM0 0x07
#define RTC_MINUTES_ALARM0 0x08
#define RTC_HOURS_ALARM0 0x09
#define RTC_DAY_OF_WEEK_ALARM0 0x0a
#define RTC_SECONDS_ALARM1 0x0b
#define RTC_MINUTES_ALARM1 0x0c
#define RTC_HOURS_ALARM1 0x0d
#define RTC_DAY_OF_WEEK_ALARM1 0x0e
#define RTC_CONTROL 0x0f
#define RTC_STATUS 0x10
#define RTC_TRICKLE_CHARGER 0x11
#define RTC_USER_RAM_BASE 0x20
static unsigned int bin2bcd (unsigned int n);
static unsigned char bcd2bin (unsigned char c);
/* ************************************************************************* */
#ifdef CONFIG_SXNI855T /* !!! SHOULD BE CHANGED TO NEW CODE !!! */
static void soft_spi_send (unsigned char n);
static unsigned char soft_spi_read (void);
static void init_spi (void);
/*-----------------------------------------------------------------------
* Definitions
*/
#define PB_SPISCK 0x00000002 /* PB 30 */
#define PB_SPIMOSI 0x00000004 /* PB 29 */
#define PB_SPIMISO 0x00000008 /* PB 28 */
#define PB_SPI_CE 0x00010000 /* PB 15 */
/* ------------------------------------------------------------------------- */
/* read clock time from DS1306 and return it in *tmp */
int rtc_get (struct rtc_time *tmp)
{
volatile immap_t *immap = (immap_t *) CFG_IMMR;
unsigned char spi_byte; /* Data Byte */
init_spi (); /* set port B for software SPI */
/* Now we can enable the DS1306 RTC */
immap->im_cpm.cp_pbdat |= PB_SPI_CE;
udelay (10);
/* Shift out the address (0) of the time in the Clock Chip */
soft_spi_send (0);
/* Put the clock readings into the rtc_time structure */
tmp->tm_sec = bcd2bin (soft_spi_read ()); /* Read seconds */
tmp->tm_min = bcd2bin (soft_spi_read ()); /* Read minutes */
/* Hours are trickier */
spi_byte = soft_spi_read (); /* Read Hours into temporary value */
if (spi_byte & 0x40) {
/* 12 hour mode bit is set (time is in 1-12 format) */
if (spi_byte & 0x20) {
/* since PM we add 11 to get 0-23 for hours */
tmp->tm_hour = (bcd2bin (spi_byte & 0x1F)) + 11;
} else {
/* since AM we subtract 1 to get 0-23 for hours */
tmp->tm_hour = (bcd2bin (spi_byte & 0x1F)) - 1;
}
} else {
/* Otherwise, 0-23 hour format */
tmp->tm_hour = (bcd2bin (spi_byte & 0x3F));
}
soft_spi_read (); /* Read and discard Day of week */
tmp->tm_mday = bcd2bin (soft_spi_read ()); /* Read Day of the Month */
tmp->tm_mon = bcd2bin (soft_spi_read ()); /* Read Month */
/* Read Year and convert to this century */
tmp->tm_year = bcd2bin (soft_spi_read ()) + 2000;
/* Now we can disable the DS1306 RTC */
immap->im_cpm.cp_pbdat &= ~PB_SPI_CE; /* Disable DS1306 Chip */
udelay (10);
GregorianDay (tmp); /* Determine the day of week */
debug ("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
return 0;
}
/* ------------------------------------------------------------------------- */
/* set clock time in DS1306 RTC and in MPC8xx RTC */
int rtc_set (struct rtc_time *tmp)
{
volatile immap_t *immap = (immap_t *) CFG_IMMR;
init_spi (); /* set port B for software SPI */
/* Now we can enable the DS1306 RTC */
immap->im_cpm.cp_pbdat |= PB_SPI_CE; /* Enable DS1306 Chip */
udelay (10);
/* First disable write protect in the clock chip control register */
soft_spi_send (0x8F); /* send address of the control register */
soft_spi_send (0x00); /* send control register contents */
/* Now disable the DS1306 to terminate the write */
immap->im_cpm.cp_pbdat &= ~PB_SPI_CE;
udelay (10);
/* Now enable the DS1306 to initiate a new write */
immap->im_cpm.cp_pbdat |= PB_SPI_CE;
udelay (10);
/* Next, send the address of the clock time write registers */
soft_spi_send (0x80); /* send address of the first time register */
/* Use Burst Mode to send all of the time data to the clock */
bin2bcd (tmp->tm_sec);
soft_spi_send (bin2bcd (tmp->tm_sec)); /* Send Seconds */
soft_spi_send (bin2bcd (tmp->tm_min)); /* Send Minutes */
soft_spi_send (bin2bcd (tmp->tm_hour)); /* Send Hour */
soft_spi_send (bin2bcd (tmp->tm_wday)); /* Send Day of the Week */
soft_spi_send (bin2bcd (tmp->tm_mday)); /* Send Day of Month */
soft_spi_send (bin2bcd (tmp->tm_mon)); /* Send Month */
soft_spi_send (bin2bcd (tmp->tm_year - 2000)); /* Send Year */
/* Now we can disable the Clock chip to terminate the burst write */
immap->im_cpm.cp_pbdat &= ~PB_SPI_CE; /* Disable DS1306 Chip */
udelay (10);
/* Now we can enable the Clock chip to initiate a new write */
immap->im_cpm.cp_pbdat |= PB_SPI_CE; /* Enable DS1306 Chip */
udelay (10);
/* First we Enable write protect in the clock chip control register */
soft_spi_send (0x8F); /* send address of the control register */
soft_spi_send (0x40); /* send out Control Register contents */
/* Now disable the DS1306 */
immap->im_cpm.cp_pbdat &= ~PB_SPI_CE; /* Disable DS1306 Chip */
udelay (10);
/* Set standard MPC8xx clock to the same time so Linux will
* see the time even if it doesn't have a DS1306 clock driver.
* This helps with experimenting with standard kernels.
*/
{
ulong tim;
tim = mktime (tmp->tm_year, tmp->tm_mon, tmp->tm_mday,
tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
immap->im_sitk.sitk_rtck = KAPWR_KEY;
immap->im_sit.sit_rtc = tim;
}
debug ("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
return 0;
}
/* ------------------------------------------------------------------------- */
/* Initialize Port B for software SPI */
static void init_spi (void)
{
volatile immap_t *immap = (immap_t *) CFG_IMMR;
/* Force output pins to begin at logic 0 */
immap->im_cpm.cp_pbdat &= ~(PB_SPI_CE | PB_SPIMOSI | PB_SPISCK);
/* Set these 3 signals as outputs */
immap->im_cpm.cp_pbdir |= (PB_SPIMOSI | PB_SPI_CE | PB_SPISCK);
immap->im_cpm.cp_pbdir &= ~PB_SPIMISO; /* Make MISO pin an input */
udelay (10);
}
/* ------------------------------------------------------------------------- */
/* NOTE: soft_spi_send() assumes that the I/O lines are configured already */
static void soft_spi_send (unsigned char n)
{
volatile immap_t *immap = (immap_t *) CFG_IMMR;
unsigned char bitpos; /* bit position to receive */
unsigned char i; /* Loop Control */
/* bit position to send, start with most significant bit */
bitpos = 0x80;
/* Send 8 bits to software SPI */
for (i = 0; i < 8; i++) { /* Loop for 8 bits */
immap->im_cpm.cp_pbdat |= PB_SPISCK; /* Raise SCK */
if (n & bitpos)
immap->im_cpm.cp_pbdat |= PB_SPIMOSI; /* Set MOSI to 1 */
else
immap->im_cpm.cp_pbdat &= ~PB_SPIMOSI; /* Set MOSI to 0 */
udelay (10);
immap->im_cpm.cp_pbdat &= ~PB_SPISCK; /* Lower SCK */
udelay (10);
bitpos >>= 1; /* Shift for next bit position */
}
}
/* ------------------------------------------------------------------------- */
/* NOTE: soft_spi_read() assumes that the I/O lines are configured already */
static unsigned char soft_spi_read (void)
{
volatile immap_t *immap = (immap_t *) CFG_IMMR;
unsigned char spi_byte = 0; /* Return value, assume success */
unsigned char bitpos; /* bit position to receive */
unsigned char i; /* Loop Control */
/* bit position to receive, start with most significant bit */
bitpos = 0x80;
/* Read 8 bits here */
for (i = 0; i < 8; i++) { /* Do 8 bits in loop */
immap->im_cpm.cp_pbdat |= PB_SPISCK; /* Raise SCK */
udelay (10);
if (immap->im_cpm.cp_pbdat & PB_SPIMISO) /* Get a bit of data */
spi_byte |= bitpos; /* Set data accordingly */
immap->im_cpm.cp_pbdat &= ~PB_SPISCK; /* Lower SCK */
udelay (10);
bitpos >>= 1; /* Shift for next bit position */
}
return spi_byte; /* Return the byte read */
}
/* ------------------------------------------------------------------------- */
void rtc_reset (void)
{
return; /* nothing to do */
}
#else /* not CONFIG_SXNI855T */
/* ************************************************************************* */
static unsigned char rtc_read (unsigned char reg);
static void rtc_write (unsigned char reg, unsigned char val);
static struct spi_slave *slave;
/* read clock time from DS1306 and return it in *tmp */
int rtc_get (struct rtc_time *tmp)
{
unsigned char sec, min, hour, mday, wday, mon, year;
/*
* Assuming Vcc = 2.0V (lowest speed)
*
* REVISIT: If we add an rtc_init() function we can do this
* step just once.
*/
if (!slave) {
slave = spi_setup_slave(0, CFG_SPI_RTC_DEVID, 600000,
SPI_MODE_3 | SPI_CS_HIGH);
if (!slave)
return;
}
if (spi_claim_bus(slave))
return;
sec = rtc_read (RTC_SECONDS);
min = rtc_read (RTC_MINUTES);
hour = rtc_read (RTC_HOURS);
mday = rtc_read (RTC_DATE_OF_MONTH);
wday = rtc_read (RTC_DAY_OF_WEEK);
mon = rtc_read (RTC_MONTH);
year = rtc_read (RTC_YEAR);
spi_release_bus(slave);
debug ("Get RTC year: %02x mon: %02x mday: %02x wday: %02x "
"hr: %02x min: %02x sec: %02x\n",
year, mon, mday, wday, hour, min, sec);
debug ("Alarms[0]: wday: %02x hour: %02x min: %02x sec: %02x\n",
rtc_read (RTC_DAY_OF_WEEK_ALARM0),
rtc_read (RTC_HOURS_ALARM0),
rtc_read (RTC_MINUTES_ALARM0), rtc_read (RTC_SECONDS_ALARM0));
debug ("Alarms[1]: wday: %02x hour: %02x min: %02x sec: %02x\n",
rtc_read (RTC_DAY_OF_WEEK_ALARM1),
rtc_read (RTC_HOURS_ALARM1),
rtc_read (RTC_MINUTES_ALARM1), rtc_read (RTC_SECONDS_ALARM1));
tmp->tm_sec = bcd2bin (sec & 0x7F); /* convert Seconds */
tmp->tm_min = bcd2bin (min & 0x7F); /* convert Minutes */
/* convert Hours */
tmp->tm_hour = (hour & 0x40)
? ((hour & 0x20) /* 12 hour mode */
? bcd2bin (hour & 0x1F) + 11 /* PM */
: bcd2bin (hour & 0x1F) - 1 /* AM */
)
: bcd2bin (hour & 0x3F); /* 24 hour mode */
tmp->tm_mday = bcd2bin (mday & 0x3F); /* convert Day of the Month */
tmp->tm_mon = bcd2bin (mon & 0x1F); /* convert Month */
tmp->tm_year = bcd2bin (year) + 2000; /* convert Year */
tmp->tm_wday = bcd2bin (wday & 0x07) - 1; /* convert Day of the Week */
tmp->tm_yday = 0;
tmp->tm_isdst = 0;
debug ("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
return 0;
}
/* ------------------------------------------------------------------------- */
/* set clock time from *tmp in DS1306 RTC */
int rtc_set (struct rtc_time *tmp)
{
/* Assuming Vcc = 2.0V (lowest speed) */
if (!slave) {
slave = spi_setup_slave(0, CFG_SPI_RTC_DEVID, 600000,
SPI_MODE_3 | SPI_CS_HIGH);
if (!slave)
return;
}
if (spi_claim_bus(slave))
return;
debug ("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
rtc_write (RTC_SECONDS, bin2bcd (tmp->tm_sec));
rtc_write (RTC_MINUTES, bin2bcd (tmp->tm_min));
rtc_write (RTC_HOURS, bin2bcd (tmp->tm_hour));
rtc_write (RTC_DAY_OF_WEEK, bin2bcd (tmp->tm_wday + 1));
rtc_write (RTC_DATE_OF_MONTH, bin2bcd (tmp->tm_mday));
rtc_write (RTC_MONTH, bin2bcd (tmp->tm_mon));
rtc_write (RTC_YEAR, bin2bcd (tmp->tm_year - 2000));
spi_release_bus(slave);
}
/* ------------------------------------------------------------------------- */
/* reset the DS1306 */
void rtc_reset (void)
{
/* Assuming Vcc = 2.0V (lowest speed) */
if (!slave) {
slave = spi_setup_slave(0, CFG_SPI_RTC_DEVID, 600000,
SPI_MODE_3 | SPI_CS_HIGH);
if (!slave)
return;
}
if (spi_claim_bus(slave))
return;
/* clear the control register */
rtc_write (RTC_CONTROL, 0x00); /* 1st step: reset WP */
rtc_write (RTC_CONTROL, 0x00); /* 2nd step: reset 1Hz, AIE1, AIE0 */
/* reset all alarms */
rtc_write (RTC_SECONDS_ALARM0, 0x00);
rtc_write (RTC_SECONDS_ALARM1, 0x00);
rtc_write (RTC_MINUTES_ALARM0, 0x00);
rtc_write (RTC_MINUTES_ALARM1, 0x00);
rtc_write (RTC_HOURS_ALARM0, 0x00);
rtc_write (RTC_HOURS_ALARM1, 0x00);
rtc_write (RTC_DAY_OF_WEEK_ALARM0, 0x00);
rtc_write (RTC_DAY_OF_WEEK_ALARM1, 0x00);
spi_release_bus(slave);
}
/* ------------------------------------------------------------------------- */
static unsigned char rtc_read (unsigned char reg)
{
int ret;
ret = spi_w8r8(slave, reg);
return ret < 0 ? 0 : ret;
}
/* ------------------------------------------------------------------------- */
static void rtc_write (unsigned char reg, unsigned char val)
{
unsigned char dout[2]; /* SPI Output Data Bytes */
unsigned char din[2]; /* SPI Input Data Bytes */
dout[0] = 0x80 | reg;
dout[1] = val;
spi_xfer (slave, 16, dout, din, SPI_XFER_BEGIN | SPI_XFER_END);
}
#endif /* end of code exclusion (see #ifdef CONFIG_SXNI855T above) */
/* ------------------------------------------------------------------------- */
static unsigned char bcd2bin (unsigned char n)
{
return ((((n >> 4) & 0x0F) * 10) + (n & 0x0F));
}
/* ------------------------------------------------------------------------- */
static unsigned int bin2bcd (unsigned int n)
{
return (((n / 10) << 4) | (n % 10));
}
/* ------------------------------------------------------------------------- */
#endif