diff options
Diffstat (limited to 'drivers/rtc')
-rw-r--r-- | drivers/rtc/rtc-max6902.c | 176 |
1 files changed, 38 insertions, 138 deletions
diff --git a/drivers/rtc/rtc-max6902.c b/drivers/rtc/rtc-max6902.c index 2f6507df7b49..36a8ea9ed8ba 100644 --- a/drivers/rtc/rtc-max6902.c +++ b/drivers/rtc/rtc-max6902.c @@ -9,14 +9,6 @@ * * Driver for MAX6902 spi RTC * - * Changelog: - * - * 24-May-2006: Raphael Assenat <raph@8d.com> - * - Major rework - * Converted to rtc_device and uses the SPI layer. - * - * ??-???-2005: Someone at Compulab - * - Initial driver creation. */ #include <linux/module.h> @@ -26,7 +18,6 @@ #include <linux/rtc.h> #include <linux/spi/spi.h> #include <linux/bcd.h> -#include <linux/delay.h> #define MAX6902_REG_SECONDS 0x01 #define MAX6902_REG_MINUTES 0x03 @@ -38,16 +29,7 @@ #define MAX6902_REG_CONTROL 0x0F #define MAX6902_REG_CENTURY 0x13 -#undef MAX6902_DEBUG - -struct max6902 { - struct rtc_device *rtc; - u8 buf[9]; /* Burst read cmd + 8 registers */ - u8 tx_buf[2]; - u8 rx_buf[2]; -}; - -static void max6902_set_reg(struct device *dev, unsigned char address, +static int max6902_set_reg(struct device *dev, unsigned char address, unsigned char data) { struct spi_device *spi = to_spi_device(dev); @@ -57,113 +39,58 @@ static void max6902_set_reg(struct device *dev, unsigned char address, buf[0] = address & 0x7f; buf[1] = data; - spi_write(spi, buf, 2); + return spi_write_then_read(spi, buf, 2, NULL, 0); } static int max6902_get_reg(struct device *dev, unsigned char address, unsigned char *data) { struct spi_device *spi = to_spi_device(dev); - struct max6902 *chip = dev_get_drvdata(dev); - struct spi_message message; - struct spi_transfer xfer; - int status; - - if (!data) - return -EINVAL; - - /* Build our spi message */ - spi_message_init(&message); - memset(&xfer, 0, sizeof(xfer)); - xfer.len = 2; - /* Can tx_buf and rx_buf be equal? The doc in spi.h is not sure... */ - xfer.tx_buf = chip->tx_buf; - xfer.rx_buf = chip->rx_buf; /* Set MSB to indicate read */ - chip->tx_buf[0] = address | 0x80; - - spi_message_add_tail(&xfer, &message); + *data = address | 0x80; - /* do the i/o */ - status = spi_sync(spi, &message); - - if (status == 0) - *data = chip->rx_buf[1]; - return status; + return spi_write_then_read(spi, data, 1, data, 1); } -static int max6902_get_datetime(struct device *dev, struct rtc_time *dt) +static int max6902_read_time(struct device *dev, struct rtc_time *dt) { - unsigned char tmp; - int century; - int err; + int err, century; struct spi_device *spi = to_spi_device(dev); - struct max6902 *chip = dev_get_drvdata(dev); - struct spi_message message; - struct spi_transfer xfer; - int status; + unsigned char buf[8]; - err = max6902_get_reg(dev, MAX6902_REG_CENTURY, &tmp); - if (err) - return err; - - /* build the message */ - spi_message_init(&message); - memset(&xfer, 0, sizeof(xfer)); - xfer.len = 1 + 7; /* Burst read command + 7 registers */ - xfer.tx_buf = chip->buf; - xfer.rx_buf = chip->buf; - chip->buf[0] = 0xbf; /* Burst read */ - spi_message_add_tail(&xfer, &message); + buf[0] = 0xbf; /* Burst read */ - /* do the i/o */ - status = spi_sync(spi, &message); - if (status) - return status; + err = spi_write_then_read(spi, buf, 1, buf, 8); + if (err != 0) + return err; /* The chip sends data in this order: * Seconds, Minutes, Hours, Date, Month, Day, Year */ - dt->tm_sec = bcd2bin(chip->buf[1]); - dt->tm_min = bcd2bin(chip->buf[2]); - dt->tm_hour = bcd2bin(chip->buf[3]); - dt->tm_mday = bcd2bin(chip->buf[4]); - dt->tm_mon = bcd2bin(chip->buf[5]) - 1; - dt->tm_wday = bcd2bin(chip->buf[6]); - dt->tm_year = bcd2bin(chip->buf[7]); + dt->tm_sec = bcd2bin(buf[0]); + dt->tm_min = bcd2bin(buf[1]); + dt->tm_hour = bcd2bin(buf[2]); + dt->tm_mday = bcd2bin(buf[3]); + dt->tm_mon = bcd2bin(buf[4]) - 1; + dt->tm_wday = bcd2bin(buf[5]); + dt->tm_year = bcd2bin(buf[6]); + + /* Read century */ + err = max6902_get_reg(dev, MAX6902_REG_CENTURY, &buf[0]); + if (err != 0) + return err; - century = bcd2bin(tmp) * 100; + century = bcd2bin(buf[0]) * 100; dt->tm_year += century; dt->tm_year -= 1900; -#ifdef MAX6902_DEBUG - printk("\n%s : Read RTC values\n",__func__); - printk("tm_hour: %i\n",dt->tm_hour); - printk("tm_min : %i\n",dt->tm_min); - printk("tm_sec : %i\n",dt->tm_sec); - printk("tm_year: %i\n",dt->tm_year); - printk("tm_mon : %i\n",dt->tm_mon); - printk("tm_mday: %i\n",dt->tm_mday); - printk("tm_wday: %i\n",dt->tm_wday); -#endif - - return 0; + return rtc_valid_tm(dt); } -static int max6902_set_datetime(struct device *dev, struct rtc_time *dt) +static int max6902_set_time(struct device *dev, struct rtc_time *dt) { - dt->tm_year = dt->tm_year+1900; - -#ifdef MAX6902_DEBUG - printk("\n%s : Setting RTC values\n",__func__); - printk("tm_sec : %i\n",dt->tm_sec); - printk("tm_min : %i\n",dt->tm_min); - printk("tm_hour: %i\n",dt->tm_hour); - printk("tm_mday: %i\n",dt->tm_mday); - printk("tm_wday: %i\n",dt->tm_wday); - printk("tm_year: %i\n",dt->tm_year); -#endif + dt->tm_year = dt->tm_year + 1900; /* Remove write protection */ max6902_set_reg(dev, 0xF, 0); @@ -173,10 +100,10 @@ static int max6902_set_datetime(struct device *dev, struct rtc_time *dt) max6902_set_reg(dev, 0x05, bin2bcd(dt->tm_hour)); max6902_set_reg(dev, 0x07, bin2bcd(dt->tm_mday)); - max6902_set_reg(dev, 0x09, bin2bcd(dt->tm_mon+1)); + max6902_set_reg(dev, 0x09, bin2bcd(dt->tm_mon + 1)); max6902_set_reg(dev, 0x0B, bin2bcd(dt->tm_wday)); - max6902_set_reg(dev, 0x0D, bin2bcd(dt->tm_year%100)); - max6902_set_reg(dev, 0x13, bin2bcd(dt->tm_year/100)); + max6902_set_reg(dev, 0x0D, bin2bcd(dt->tm_year % 100)); + max6902_set_reg(dev, 0x13, bin2bcd(dt->tm_year / 100)); /* Compulab used a delay here. However, the datasheet * does not mention a delay being required anywhere... */ @@ -188,16 +115,6 @@ static int max6902_set_datetime(struct device *dev, struct rtc_time *dt) return 0; } -static int max6902_read_time(struct device *dev, struct rtc_time *tm) -{ - return max6902_get_datetime(dev, tm); -} - -static int max6902_set_time(struct device *dev, struct rtc_time *tm) -{ - return max6902_set_datetime(dev, tm); -} - static const struct rtc_class_ops max6902_rtc_ops = { .read_time = max6902_read_time, .set_time = max6902_set_time, @@ -207,45 +124,29 @@ static int __devinit max6902_probe(struct spi_device *spi) { struct rtc_device *rtc; unsigned char tmp; - struct max6902 *chip; int res; - rtc = rtc_device_register("max6902", - &spi->dev, &max6902_rtc_ops, THIS_MODULE); - if (IS_ERR(rtc)) - return PTR_ERR(rtc); - spi->mode = SPI_MODE_3; spi->bits_per_word = 8; spi_setup(spi); - chip = kzalloc(sizeof *chip, GFP_KERNEL); - if (!chip) { - rtc_device_unregister(rtc); - return -ENOMEM; - } - chip->rtc = rtc; - dev_set_drvdata(&spi->dev, chip); - res = max6902_get_reg(&spi->dev, MAX6902_REG_SECONDS, &tmp); - if (res) { - rtc_device_unregister(rtc); + if (res != 0) return res; - } + + rtc = rtc_device_register("max6902", + &spi->dev, &max6902_rtc_ops, THIS_MODULE); + if (IS_ERR(rtc)) + return PTR_ERR(rtc); return 0; } static int __devexit max6902_remove(struct spi_device *spi) { - struct max6902 *chip = platform_get_drvdata(spi); - struct rtc_device *rtc = chip->rtc; - - if (rtc) - rtc_device_unregister(rtc); - - kfree(chip); + struct rtc_device *rtc = platform_get_drvdata(spi); + rtc_device_unregister(rtc); return 0; } @@ -261,7 +162,6 @@ static struct spi_driver max6902_driver = { static __init int max6902_init(void) { - printk("max6902 spi driver\n"); return spi_register_driver(&max6902_driver); } module_init(max6902_init); |