| Message ID | 1476261212-5754-1-git-send-email-venkat.prashanth2498@gmail.com |
|---|---|
| State | Rejected |
| Headers | show |
Hi, Seeing this has the same register map as max6916, please use regmap to abstract the accesses and handle both with the same driver. You can have a look at rtc-ds3232.c for an example. On 12/10/2016 at 01:33:32 -0700, VENKAT PRASHANTH B U wrote : > This is a patch to add support for > maxim dallas rtc max6917. > > Signed-off-by: Venkat Prashanth B U <venkat.prashanth2498@gmail.com> > --- > --- > drivers/rtc/Kconfig | 9 + > drivers/rtc/Makefile | 1 + > drivers/rtc/rtc-max6917.c | 406 ++++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 416 insertions(+) > > diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig > index e215f50..2163606 100644 > --- a/drivers/rtc/Kconfig > +++ b/drivers/rtc/Kconfig > @@ -277,6 +277,15 @@ config RTC_DRV_MAX6900 > This driver can also be built as a module. If so, the module > will be called rtc-max6900. > > +config RTC_DRV_MAX6917 > + tristate "Maxim MAX6917" > + help > + If you say yes here you will get support for the > + Maxim MAX6917 I2C RTC chip. > + > + This driver can also be built as a module. If so, the module > + will be called rtc-max6917. > + > config RTC_DRV_MAX8907 > tristate "Maxim MAX8907" > depends on MFD_MAX8907 > diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile > index 7cf7ad5..29332fb 100644 > --- a/drivers/rtc/Makefile > +++ b/drivers/rtc/Makefile > @@ -87,6 +87,7 @@ obj-$(CONFIG_RTC_DRV_M48T86) += rtc-m48t86.o > obj-$(CONFIG_RTC_DRV_MAX6900) += rtc-max6900.o > obj-$(CONFIG_RTC_DRV_MAX6902) += rtc-max6902.o > obj-$(CONFIG_RTC_DRV_MAX6916) += rtc-max6916.o > +obj-$(CONFIG_RTC_DRV_MAX6917) += rtc-max6917.o > obj-$(CONFIG_RTC_DRV_MAX77686) += rtc-max77686.o > obj-$(CONFIG_RTC_DRV_MAX8907) += rtc-max8907.o > obj-$(CONFIG_RTC_DRV_MAX8925) += rtc-max8925.o > diff --git a/drivers/rtc/rtc-max6917.c b/drivers/rtc/rtc-max6917.c > index e69de29..1176384 100644 > --- a/drivers/rtc/rtc-max6917.c > +++ b/drivers/rtc/rtc-max6917.c > @@ -0,0 +1,406 @@ > + /* rtc-max6917.c > + * > + * Driver for MAXIM max6917 I2C-Compatible Real Time Clock > + * > + * Author : Venkat Prashanth B U <venkat.prashanth2498@gmail.com> > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + * > + */ > + > + #include <linux/bcd.h> > + #include <linux/i2c.h> > + #include <linux/init.h> > + #include <linux/module.h> > + #include <linux/rtc.h> > + #include <linux/string.h> > + #include <linux/delay.h> > + #include <linux/clk-provider.h> > + #include <linux/slab.h> > + > + #define MAX6917_REG_SECS 0x01 /* 00-59 */ > + #define MAX6917_REG_MIN 0x02 /* 00-59 */ > + #define MAX6917_REG_HOUR 0x03 /* 00-23, or 1-12{am,pm} */ > + #define MAX6917_REG_WDAY 0x04 /* 01-07 */ > + #define MAX6917_REG_MDAY 0x05 /* 01-31 */ > + #define MAX6917_REG_MONTH 0x06 /* 01-12 */ > + #define MAX6917_REG_YEAR 0x07 /* 00-99 */ > + #define MAX6917_REG_CONTROL 0x08 > + #define MAX6917_REG_STATUS 0x0c > + #define MAX6917_REG_ALARM 0x0a > + #define MAX6917_BURST_LEN 8 /* can burst r/w first 8 regs */ > + #define MAX6917_REG_CENTURY 9 /* century */ > + #define MAX6917_REG_LEN 10 > + #define MAX6917_REG_CT_WP (1 << 7) /* Write Protect */ > + /* > + * register read/write commands > + */ > + #define MAX6917_REG_CONTROL_WRITE 0x8e > + #define MAX6917_REG_CENTURY_WRITE 0x92 > + #define MAX6917_REG_CENTURY_READ 0x93 > + #define MAX6917_REG_RESERVED_READ 0x96 > + #define MAX6917_REG_BURST_WRITE 0xbe > + #define MAX6917_REG_BURST_READ 0xbf > + > + #define MAX6917_IDLE_TIME_AFTER_WRITE 3 /* specification says 2.5 mS */ > + > + static struct i2c_driver max6917_driver; > + > + struct max6917 > + { > + u8 offset; /* register's offset */ > + u8 regs[11]; > + u16 nvram_offset; > + struct bin_attribute *nvram; > + unsigned long flags; > + #define HAS_NVRAM 0 /* bit 0 == sysfs file active */ > + #define HAS_ALARM 1 /* bit 1 == irq claimed */ > + struct i2c_client *client; > + struct rtc_device *rtc; > + s32 (*read_block_data) (const struct i2c_client * client, u8 command, > + u8 length, u8 * values); > + s32 (*write_block_data) (const struct i2c_client * client, u8 command, > + u8 length, const u8 * values); > + }; > + > + struct chip_desc > + { > + unsigned alarm:1; > + u16 nvram_offset; > + u16 nvram_size; > + }; > + > + static int > + max6917_i2c_read_regs (struct i2c_client *client, u8 * buf) > + { > + u8 reg_burst_read[1] = { MAX6917_REG_BURST_READ }; > + u8 reg_century_read[1] = { MAX6917_REG_CENTURY_READ }; > + struct i2c_msg msgs[4] = { > + { > + .addr = client->addr, > + .flags = 0, /* write */ > + .len = sizeof (reg_burst_read), > + .buf = reg_burst_read} > + , > + { > + .addr = client->addr, > + .flags = I2C_M_RD, > + .len = MAX6917_BURST_LEN, > + .buf = buf} > + , > + { > + .addr = client->addr, > + .flags = 0, /* write */ > + .len = sizeof (reg_century_read), > + .buf = reg_century_read} > + , > + { > + .addr = client->addr, > + .flags = I2C_M_RD, > + .len = sizeof (buf[MAX6917_REG_CENTURY]), > + .buf = &buf[MAX6917_REG_CENTURY]} > + }; > + int rc; > + > + rc = i2c_transfer (client->adapter, msgs, ARRAY_SIZE (msgs)); > + if (rc != ARRAY_SIZE (msgs)) > + { > + dev_err (&client->dev, "%s: register read failed\n", __func__); > + return -EIO; > + } > + return 0; > + } > + > + static int > + max6917_i2c_write_regs (struct i2c_client *client, u8 const *buf) > + { > + u8 i2c_century_buf[1 + 1] = { MAX6917_REG_CENTURY_WRITE }; > + struct i2c_msg century_msgs[1] = { > + { > + .addr = client->addr, > + .flags = 0, /* write */ > + .len = sizeof (i2c_century_buf), > + .buf = i2c_century_buf} > + }; > + u8 i2c_burst_buf[MAX6917_BURST_LEN + 1] = { MAX6917_REG_BURST_WRITE }; > + struct i2c_msg burst_msgs[1] = { > + { > + .addr = client->addr, > + .flags = 0, /* write */ > + .len = sizeof (i2c_burst_buf), > + .buf = i2c_burst_buf} > + }; > + int rc; > + > + /* > + * We have to make separate calls to i2c_transfer because of > + * the need to delay after each write to the chip. Also, > + * we write the century byte first, since we set the write-protect > + * bit as part of the burst write. > + */ > + i2c_century_buf[1] = buf[MAX6917_REG_CENTURY]; > + > + rc = i2c_transfer (client->adapter, century_msgs, > + ARRAY_SIZE (century_msgs)); > + if (rc != ARRAY_SIZE (century_msgs)) > + goto write_failed; > + > + msleep (MAX6917_IDLE_TIME_AFTER_WRITE); > + > + memcpy (&i2c_burst_buf[1], buf, MAX6917_BURST_LEN); > + > + rc = i2c_transfer (client->adapter, burst_msgs, ARRAY_SIZE (burst_msgs)); > + if (rc != ARRAY_SIZE (burst_msgs)) > + goto write_failed; > + msleep (MAX6917_IDLE_TIME_AFTER_WRITE); > + > + return 0; > + > + write_failed: > + dev_err (&client->dev, "%s: register write failed\n", __func__); > + return -EIO; > + } > + > + static int > + max6917_i2c_read_time (struct i2c_client *client, struct rtc_time *tm) > + { > + int rc; > + u8 regs[MAX6917_REG_LEN]; > + > + rc = max6917_i2c_read_regs (client, regs); > + if (rc < 0) > + return rc; > + > + tm->tm_sec = bcd2bin (regs[MAX6917_REG_SECS]); > + tm->tm_min = bcd2bin (regs[MAX6917_REG_MIN]); > + tm->tm_hour = bcd2bin (regs[MAX6917_REG_HOUR] & 0x3f); > + tm->tm_mday = bcd2bin (regs[MAX6917_REG_MDAY]); > + tm->tm_mon = bcd2bin (regs[MAX6917_REG_MONTH]) - 1; > + tm->tm_year = bcd2bin (regs[MAX6917_REG_YEAR]) + > + bcd2bin (regs[MAX6917_REG_CENTURY]) * 100 - 1900; > + tm->tm_wday = bcd2bin (regs[MAX6917_REG_WDAY]); > + > + return rtc_valid_tm (tm); > + } > + > + static int > + max6917_i2c_clear_write_protect (struct i2c_client *client) > + { > + return i2c_smbus_write_byte_data (client, MAX6917_REG_CONTROL_WRITE, 0); > + } > + > + static int > + max6917_i2c_set_time (struct i2c_client *client, struct rtc_time const *tm) > + { > + u8 regs[MAX6917_REG_LEN]; > + int rc; > + > + rc = max6917_i2c_clear_write_protect (client); > + if (rc < 0) > + return rc; > + > + regs[MAX6917_REG_SECS] = bin2bcd (tm->tm_sec); > + regs[MAX6917_REG_MIN] = bin2bcd (tm->tm_min); > + regs[MAX6917_REG_HOUR] = bin2bcd (tm->tm_hour); > + regs[MAX6917_REG_MDAY] = bin2bcd (tm->tm_mday); > + regs[MAX6917_REG_MONTH] = bin2bcd (tm->tm_mon + 1); > + regs[MAX6917_REG_WDAY] = bin2bcd (tm->tm_wday); > + regs[MAX6917_REG_YEAR] = bin2bcd (tm->tm_year % 100); > + regs[MAX6917_REG_CENTURY] = bin2bcd ((tm->tm_year + 1900) / 100); > + /* set write protect */ > + regs[MAX6917_REG_CONTROL] = MAX6917_REG_CT_WP; > + > + rc = max6917_i2c_write_regs (client, regs); > + if (rc < 0) > + return rc; > + > + return 0; > + } > + > + static int > + max6917_rtc_read_time (struct device *dev, struct rtc_time *tm) > + { > + return max6917_i2c_read_time (to_i2c_client (dev), tm); > + } > + > + static int > + max6917_rtc_set_time (struct device *dev, struct rtc_time *tm) > + { > + return max6917_i2c_set_time (to_i2c_client (dev), tm); > + } > + > + static int > + max6917_read_alarm (struct device *dev, struct rtc_wkalrm *t) > + { > + struct i2c_client *client = to_i2c_client (dev); > + struct max6917 *max6917 = i2c_get_clientdata (client); > + int ret; > + > + if (!test_bit (HAS_ALARM, &max6917->flags)) > + return -EINVAL; > + > + /* read all ALARM1, ALARM2, and status registers at once */ > + ret = max6917->read_block_data (client, > + MAX6917_REG_ALARM, 9, max6917->regs); > + if (ret != 9) > + { > + dev_err (dev, " error %d\n", "alarm read", ret); > + return -EIO; > + } > + > + dev_dbg (dev, "%4ph, %3ph, %2ph\n", "alarm read", > + &max6917->regs[0], &max6917->regs[4], &max6917->regs[7]); > + > + /* > + * report alarm time (ALARM1); assume 24 hour and day-of-month modes, > + * and that all four fields are checked matches > + */ > + t->time.tm_sec = bcd2bin (max6917->regs[0] & 0x7f); > + t->time.tm_min = bcd2bin (max6917->regs[1] & 0x7f); > + t->time.tm_hour = bcd2bin (max6917->regs[2] & 0x3f); > + t->time.tm_mday = bcd2bin (max6917->regs[3] & 0x3f); > + > + dev_dbg (dev, " %s secs=%d, mins=%d, " > + "hours=%d, mday=%d, enabled=%d, pending=%d\n", > + "alarm read", t->time.tm_sec, t->time.tm_min, > + t->time.tm_hour, t->time.tm_mday); > + > + return 0; > + } > + > + static int > + max6917_set_alarm (struct device *dev, struct rtc_wkalrm *t) > + { > + struct i2c_client *client = to_i2c_client (dev); > + struct max6917 *max6917 = i2c_get_clientdata (client); > + unsigned char *buf = max6917->regs; > + u8 control, status; > + int ret; > + > + if (!test_bit (HAS_ALARM, &max6917->flags)) > + return -EINVAL; > + > + dev_dbg (dev, " %s secs=%d, mins=%d, " > + "hours=%d, mday=%d, enabled=%d, pending=%d\n", > + "alarm set", t->time.tm_sec, t->time.tm_min, > + t->time.tm_hour, t->time.tm_mday); > + > + /* read current status of both alarms and the chip */ > + ret = max6917->read_block_data (client, MAX6917_REG_ALARM, 9, buf); > + if (ret != 9) > + { > + dev_err (dev, "%s error %d\n", "alarm write", ret); > + return -EIO; > + } > + control = max6917->regs[7]; > + status = max6917->regs[8]; > + > + dev_dbg (dev, "%s: %4ph, %3ph, %02x %02x\n", "alarm set (old status)", > + &max6917->regs[0], &max6917->regs[4], control, status); > + > + /* set ALARM1, using 24 hour and day-of-month modes */ > + buf[0] = bin2bcd (t->time.tm_sec); > + buf[1] = bin2bcd (t->time.tm_min); > + buf[2] = bin2bcd (t->time.tm_hour); > + buf[3] = bin2bcd (t->time.tm_mday); > + buf[4] = 0; > + buf[5] = 0; > + buf[6] = 0; > + > + ret = max6917->write_block_data (client, MAX6917_REG_ALARM, 9, buf); > + if (ret < 0) > + { > + dev_err (dev, "can't set alarm time\n"); > + return ret; > + } > + return 0; > + } > + > + static ssize_t > + max6917_nvram_read (struct file *filp, struct kobject *kobj, > + struct bin_attribute *attr, > + char *buf, loff_t off, size_t count) > + { > + struct i2c_client *client; > + struct max6917 *max6917; > + int result; > + > + client = kobj_to_i2c_client (kobj); > + max6917 = i2c_get_clientdata (client); > + > + result = max6917->read_block_data (client, max6917->nvram_offset + off, > + count, buf); > + if (result < 0) > + dev_err (&client->dev, "%s error %d\n", "nvram read", result); > + return result; > + } > + > + static ssize_t > + max6917_nvram_write (struct file *filp, struct kobject *kobj, > + struct bin_attribute *attr, > + char *buf, loff_t off, size_t count) > + { > + struct i2c_client *client; > + struct max6917 *max6917; > + int result; > + > + client = kobj_to_i2c_client (kobj); > + max6917 = i2c_get_clientdata (client); > + > + result = max6917->write_block_data (client, max6917->nvram_offset + off, > + count, buf); > + if (result < 0) > + { > + dev_err (&client->dev, "%s error %d\n", "nvram write", result); > + return result; > + } > + return count; > + } > + > + static const struct rtc_class_ops max6917_rtc_ops = { > + .read_time = max6917_rtc_read_time, > + .set_time = max6917_rtc_set_time, > + .read_alarm = max6917_read_alarm, > + .set_alarm = max6917_set_alarm, > + }; > + > + static int > + max6917_probe (struct i2c_client *client, const struct i2c_device_id *id) > + { > + struct rtc_device *rtc; > + > + if (!i2c_check_functionality (client->adapter, I2C_FUNC_I2C)) > + return -ENODEV; > + > + rtc = devm_rtc_device_register (&client->dev, max6917_driver.driver.name, > + &max6917_rtc_ops, THIS_MODULE); > + if (IS_ERR (rtc)) > + return PTR_ERR (rtc); > + > + i2c_set_clientdata (client, rtc); > + > + return 0; > + } > + > + static struct i2c_device_id max6917_id[] = { > + {"max6917", 0}, > + {} > + }; > + > + MODULE_DEVICE_TABLE (i2c, max6917_id); > + > + static struct i2c_driver max6917_driver = { > + .driver = { > + .name = "rtc-max6917", > + }, > + .probe = max6917_probe, > + .id_table = max6917_id, > + }; > + > + module_i2c_driver (max6917_driver); > + > + MODULE_DESCRIPTION ("Maxim MAX6917 RTC driver"); > + MODULE_AUTHOR ("Venkat Prashanth B U"); > + MODULE_LICENSE ("GPL"); > -- > 1.9.2 > > -- > You received this message because you are subscribed to "rtc-linux". > Membership options at http://groups.google.com/group/rtc-linux . > Please read http://groups.google.com/group/rtc-linux/web/checklist > before submitting a driver. > --- > You received this message because you are subscribed to the Google Groups "rtc-linux" group. > To unsubscribe from this group and stop receiving emails from it, send an email to rtc-linux+unsubscribe@googlegroups.com. > For more options, visit https://groups.google.com/d/optout.
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index e215f50..2163606 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -277,6 +277,15 @@ config RTC_DRV_MAX6900 This driver can also be built as a module. If so, the module will be called rtc-max6900. +config RTC_DRV_MAX6917 + tristate "Maxim MAX6917" + help + If you say yes here you will get support for the + Maxim MAX6917 I2C RTC chip. + + This driver can also be built as a module. If so, the module + will be called rtc-max6917. + config RTC_DRV_MAX8907 tristate "Maxim MAX8907" depends on MFD_MAX8907 diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index 7cf7ad5..29332fb 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -87,6 +87,7 @@ obj-$(CONFIG_RTC_DRV_M48T86) += rtc-m48t86.o obj-$(CONFIG_RTC_DRV_MAX6900) += rtc-max6900.o obj-$(CONFIG_RTC_DRV_MAX6902) += rtc-max6902.o obj-$(CONFIG_RTC_DRV_MAX6916) += rtc-max6916.o +obj-$(CONFIG_RTC_DRV_MAX6917) += rtc-max6917.o obj-$(CONFIG_RTC_DRV_MAX77686) += rtc-max77686.o obj-$(CONFIG_RTC_DRV_MAX8907) += rtc-max8907.o obj-$(CONFIG_RTC_DRV_MAX8925) += rtc-max8925.o diff --git a/drivers/rtc/rtc-max6917.c b/drivers/rtc/rtc-max6917.c index e69de29..1176384 100644 --- a/drivers/rtc/rtc-max6917.c +++ b/drivers/rtc/rtc-max6917.c @@ -0,0 +1,406 @@ + /* rtc-max6917.c + * + * Driver for MAXIM max6917 I2C-Compatible Real Time Clock + * + * Author : Venkat Prashanth B U <venkat.prashanth2498@gmail.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + + #include <linux/bcd.h> + #include <linux/i2c.h> + #include <linux/init.h> + #include <linux/module.h> + #include <linux/rtc.h> + #include <linux/string.h> + #include <linux/delay.h> + #include <linux/clk-provider.h> + #include <linux/slab.h> + + #define MAX6917_REG_SECS 0x01 /* 00-59 */ + #define MAX6917_REG_MIN 0x02 /* 00-59 */ + #define MAX6917_REG_HOUR 0x03 /* 00-23, or 1-12{am,pm} */ + #define MAX6917_REG_WDAY 0x04 /* 01-07 */ + #define MAX6917_REG_MDAY 0x05 /* 01-31 */ + #define MAX6917_REG_MONTH 0x06 /* 01-12 */ + #define MAX6917_REG_YEAR 0x07 /* 00-99 */ + #define MAX6917_REG_CONTROL 0x08 + #define MAX6917_REG_STATUS 0x0c + #define MAX6917_REG_ALARM 0x0a + #define MAX6917_BURST_LEN 8 /* can burst r/w first 8 regs */ + #define MAX6917_REG_CENTURY 9 /* century */ + #define MAX6917_REG_LEN 10 + #define MAX6917_REG_CT_WP (1 << 7) /* Write Protect */ + /* + * register read/write commands + */ + #define MAX6917_REG_CONTROL_WRITE 0x8e + #define MAX6917_REG_CENTURY_WRITE 0x92 + #define MAX6917_REG_CENTURY_READ 0x93 + #define MAX6917_REG_RESERVED_READ 0x96 + #define MAX6917_REG_BURST_WRITE 0xbe + #define MAX6917_REG_BURST_READ 0xbf + + #define MAX6917_IDLE_TIME_AFTER_WRITE 3 /* specification says 2.5 mS */ + + static struct i2c_driver max6917_driver; + + struct max6917 + { + u8 offset; /* register's offset */ + u8 regs[11]; + u16 nvram_offset; + struct bin_attribute *nvram; + unsigned long flags; + #define HAS_NVRAM 0 /* bit 0 == sysfs file active */ + #define HAS_ALARM 1 /* bit 1 == irq claimed */ + struct i2c_client *client; + struct rtc_device *rtc; + s32 (*read_block_data) (const struct i2c_client * client, u8 command, + u8 length, u8 * values); + s32 (*write_block_data) (const struct i2c_client * client, u8 command, + u8 length, const u8 * values); + }; + + struct chip_desc + { + unsigned alarm:1; + u16 nvram_offset; + u16 nvram_size; + }; + + static int + max6917_i2c_read_regs (struct i2c_client *client, u8 * buf) + { + u8 reg_burst_read[1] = { MAX6917_REG_BURST_READ }; + u8 reg_century_read[1] = { MAX6917_REG_CENTURY_READ }; + struct i2c_msg msgs[4] = { + { + .addr = client->addr, + .flags = 0, /* write */ + .len = sizeof (reg_burst_read), + .buf = reg_burst_read} + , + { + .addr = client->addr, + .flags = I2C_M_RD, + .len = MAX6917_BURST_LEN, + .buf = buf} + , + { + .addr = client->addr, + .flags = 0, /* write */ + .len = sizeof (reg_century_read), + .buf = reg_century_read} + , + { + .addr = client->addr, + .flags = I2C_M_RD, + .len = sizeof (buf[MAX6917_REG_CENTURY]), + .buf = &buf[MAX6917_REG_CENTURY]} + }; + int rc; + + rc = i2c_transfer (client->adapter, msgs, ARRAY_SIZE (msgs)); + if (rc != ARRAY_SIZE (msgs)) + { + dev_err (&client->dev, "%s: register read failed\n", __func__); + return -EIO; + } + return 0; + } + + static int + max6917_i2c_write_regs (struct i2c_client *client, u8 const *buf) + { + u8 i2c_century_buf[1 + 1] = { MAX6917_REG_CENTURY_WRITE }; + struct i2c_msg century_msgs[1] = { + { + .addr = client->addr, + .flags = 0, /* write */ + .len = sizeof (i2c_century_buf), + .buf = i2c_century_buf} + }; + u8 i2c_burst_buf[MAX6917_BURST_LEN + 1] = { MAX6917_REG_BURST_WRITE }; + struct i2c_msg burst_msgs[1] = { + { + .addr = client->addr, + .flags = 0, /* write */ + .len = sizeof (i2c_burst_buf), + .buf = i2c_burst_buf} + }; + int rc; + + /* + * We have to make separate calls to i2c_transfer because of + * the need to delay after each write to the chip. Also, + * we write the century byte first, since we set the write-protect + * bit as part of the burst write. + */ + i2c_century_buf[1] = buf[MAX6917_REG_CENTURY]; + + rc = i2c_transfer (client->adapter, century_msgs, + ARRAY_SIZE (century_msgs)); + if (rc != ARRAY_SIZE (century_msgs)) + goto write_failed; + + msleep (MAX6917_IDLE_TIME_AFTER_WRITE); + + memcpy (&i2c_burst_buf[1], buf, MAX6917_BURST_LEN); + + rc = i2c_transfer (client->adapter, burst_msgs, ARRAY_SIZE (burst_msgs)); + if (rc != ARRAY_SIZE (burst_msgs)) + goto write_failed; + msleep (MAX6917_IDLE_TIME_AFTER_WRITE); + + return 0; + + write_failed: + dev_err (&client->dev, "%s: register write failed\n", __func__); + return -EIO; + } + + static int + max6917_i2c_read_time (struct i2c_client *client, struct rtc_time *tm) + { + int rc; + u8 regs[MAX6917_REG_LEN]; + + rc = max6917_i2c_read_regs (client, regs); + if (rc < 0) + return rc; + + tm->tm_sec = bcd2bin (regs[MAX6917_REG_SECS]); + tm->tm_min = bcd2bin (regs[MAX6917_REG_MIN]); + tm->tm_hour = bcd2bin (regs[MAX6917_REG_HOUR] & 0x3f); + tm->tm_mday = bcd2bin (regs[MAX6917_REG_MDAY]); + tm->tm_mon = bcd2bin (regs[MAX6917_REG_MONTH]) - 1; + tm->tm_year = bcd2bin (regs[MAX6917_REG_YEAR]) + + bcd2bin (regs[MAX6917_REG_CENTURY]) * 100 - 1900; + tm->tm_wday = bcd2bin (regs[MAX6917_REG_WDAY]); + + return rtc_valid_tm (tm); + } + + static int + max6917_i2c_clear_write_protect (struct i2c_client *client) + { + return i2c_smbus_write_byte_data (client, MAX6917_REG_CONTROL_WRITE, 0); + } + + static int + max6917_i2c_set_time (struct i2c_client *client, struct rtc_time const *tm) + { + u8 regs[MAX6917_REG_LEN]; + int rc; + + rc = max6917_i2c_clear_write_protect (client); + if (rc < 0) + return rc; + + regs[MAX6917_REG_SECS] = bin2bcd (tm->tm_sec); + regs[MAX6917_REG_MIN] = bin2bcd (tm->tm_min); + regs[MAX6917_REG_HOUR] = bin2bcd (tm->tm_hour); + regs[MAX6917_REG_MDAY] = bin2bcd (tm->tm_mday); + regs[MAX6917_REG_MONTH] = bin2bcd (tm->tm_mon + 1); + regs[MAX6917_REG_WDAY] = bin2bcd (tm->tm_wday); + regs[MAX6917_REG_YEAR] = bin2bcd (tm->tm_year % 100); + regs[MAX6917_REG_CENTURY] = bin2bcd ((tm->tm_year + 1900) / 100); + /* set write protect */ + regs[MAX6917_REG_CONTROL] = MAX6917_REG_CT_WP; + + rc = max6917_i2c_write_regs (client, regs); + if (rc < 0) + return rc; + + return 0; + } + + static int + max6917_rtc_read_time (struct device *dev, struct rtc_time *tm) + { + return max6917_i2c_read_time (to_i2c_client (dev), tm); + } + + static int + max6917_rtc_set_time (struct device *dev, struct rtc_time *tm) + { + return max6917_i2c_set_time (to_i2c_client (dev), tm); + } + + static int + max6917_read_alarm (struct device *dev, struct rtc_wkalrm *t) + { + struct i2c_client *client = to_i2c_client (dev); + struct max6917 *max6917 = i2c_get_clientdata (client); + int ret; + + if (!test_bit (HAS_ALARM, &max6917->flags)) + return -EINVAL; + + /* read all ALARM1, ALARM2, and status registers at once */ + ret = max6917->read_block_data (client, + MAX6917_REG_ALARM, 9, max6917->regs); + if (ret != 9) + { + dev_err (dev, " error %d\n", "alarm read", ret); + return -EIO; + } + + dev_dbg (dev, "%4ph, %3ph, %2ph\n", "alarm read", + &max6917->regs[0], &max6917->regs[4], &max6917->regs[7]); + + /* + * report alarm time (ALARM1); assume 24 hour and day-of-month modes, + * and that all four fields are checked matches + */ + t->time.tm_sec = bcd2bin (max6917->regs[0] & 0x7f); + t->time.tm_min = bcd2bin (max6917->regs[1] & 0x7f); + t->time.tm_hour = bcd2bin (max6917->regs[2] & 0x3f); + t->time.tm_mday = bcd2bin (max6917->regs[3] & 0x3f); + + dev_dbg (dev, " %s secs=%d, mins=%d, " + "hours=%d, mday=%d, enabled=%d, pending=%d\n", + "alarm read", t->time.tm_sec, t->time.tm_min, + t->time.tm_hour, t->time.tm_mday); + + return 0; + } + + static int + max6917_set_alarm (struct device *dev, struct rtc_wkalrm *t) + { + struct i2c_client *client = to_i2c_client (dev); + struct max6917 *max6917 = i2c_get_clientdata (client); + unsigned char *buf = max6917->regs; + u8 control, status; + int ret; + + if (!test_bit (HAS_ALARM, &max6917->flags)) + return -EINVAL; + + dev_dbg (dev, " %s secs=%d, mins=%d, " + "hours=%d, mday=%d, enabled=%d, pending=%d\n", + "alarm set", t->time.tm_sec, t->time.tm_min, + t->time.tm_hour, t->time.tm_mday); + + /* read current status of both alarms and the chip */ + ret = max6917->read_block_data (client, MAX6917_REG_ALARM, 9, buf); + if (ret != 9) + { + dev_err (dev, "%s error %d\n", "alarm write", ret); + return -EIO; + } + control = max6917->regs[7]; + status = max6917->regs[8]; + + dev_dbg (dev, "%s: %4ph, %3ph, %02x %02x\n", "alarm set (old status)", + &max6917->regs[0], &max6917->regs[4], control, status); + + /* set ALARM1, using 24 hour and day-of-month modes */ + buf[0] = bin2bcd (t->time.tm_sec); + buf[1] = bin2bcd (t->time.tm_min); + buf[2] = bin2bcd (t->time.tm_hour); + buf[3] = bin2bcd (t->time.tm_mday); + buf[4] = 0; + buf[5] = 0; + buf[6] = 0; + + ret = max6917->write_block_data (client, MAX6917_REG_ALARM, 9, buf); + if (ret < 0) + { + dev_err (dev, "can't set alarm time\n"); + return ret; + } + return 0; + } + + static ssize_t + max6917_nvram_read (struct file *filp, struct kobject *kobj, + struct bin_attribute *attr, + char *buf, loff_t off, size_t count) + { + struct i2c_client *client; + struct max6917 *max6917; + int result; + + client = kobj_to_i2c_client (kobj); + max6917 = i2c_get_clientdata (client); + + result = max6917->read_block_data (client, max6917->nvram_offset + off, + count, buf); + if (result < 0) + dev_err (&client->dev, "%s error %d\n", "nvram read", result); + return result; + } + + static ssize_t + max6917_nvram_write (struct file *filp, struct kobject *kobj, + struct bin_attribute *attr, + char *buf, loff_t off, size_t count) + { + struct i2c_client *client; + struct max6917 *max6917; + int result; + + client = kobj_to_i2c_client (kobj); + max6917 = i2c_get_clientdata (client); + + result = max6917->write_block_data (client, max6917->nvram_offset + off, + count, buf); + if (result < 0) + { + dev_err (&client->dev, "%s error %d\n", "nvram write", result); + return result; + } + return count; + } + + static const struct rtc_class_ops max6917_rtc_ops = { + .read_time = max6917_rtc_read_time, + .set_time = max6917_rtc_set_time, + .read_alarm = max6917_read_alarm, + .set_alarm = max6917_set_alarm, + }; + + static int + max6917_probe (struct i2c_client *client, const struct i2c_device_id *id) + { + struct rtc_device *rtc; + + if (!i2c_check_functionality (client->adapter, I2C_FUNC_I2C)) + return -ENODEV; + + rtc = devm_rtc_device_register (&client->dev, max6917_driver.driver.name, + &max6917_rtc_ops, THIS_MODULE); + if (IS_ERR (rtc)) + return PTR_ERR (rtc); + + i2c_set_clientdata (client, rtc); + + return 0; + } + + static struct i2c_device_id max6917_id[] = { + {"max6917", 0}, + {} + }; + + MODULE_DEVICE_TABLE (i2c, max6917_id); + + static struct i2c_driver max6917_driver = { + .driver = { + .name = "rtc-max6917", + }, + .probe = max6917_probe, + .id_table = max6917_id, + }; + + module_i2c_driver (max6917_driver); + + MODULE_DESCRIPTION ("Maxim MAX6917 RTC driver"); + MODULE_AUTHOR ("Venkat Prashanth B U"); + MODULE_LICENSE ("GPL");
This is a patch to add support for maxim dallas rtc max6917. Signed-off-by: Venkat Prashanth B U <venkat.prashanth2498@gmail.com> --- --- drivers/rtc/Kconfig | 9 + drivers/rtc/Makefile | 1 + drivers/rtc/rtc-max6917.c | 406 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 416 insertions(+)