Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754163AbcJLLkG (ORCPT ); Wed, 12 Oct 2016 07:40:06 -0400 Received: from down.free-electrons.com ([37.187.137.238]:51816 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753449AbcJLLj7 (ORCPT ); Wed, 12 Oct 2016 07:39:59 -0400 Date: Wed, 12 Oct 2016 13:39:46 +0200 From: Alexandre Belloni To: VENKAT PRASHANTH B U Cc: rtc-linux@googlegroups.com, linux-kernel@vger.kernel.org Subject: Re: [rtc-linux] [PATCH] rtc: Add support for maxim dallas rtc max-6917 Message-ID: <20161012113946.pr2mi5j3watelpng@piout.net> References: <1476261212-5754-1-git-send-email-venkat.prashanth2498@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1476261212-5754-1-git-send-email-venkat.prashanth2498@gmail.com> User-Agent: NeoMutt/20160916 (1.7.0) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 14626 Lines: 478 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 > --- > --- > 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 > + * > + * 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 > + #include > + #include > + #include > + #include > + #include > + #include > + #include > + #include > + > + #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. -- Alexandre Belloni, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com