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Diffstat (limited to 'drivers/i2c/chips/ds1374.c')
-rw-r--r--drivers/i2c/chips/ds1374.c267
1 files changed, 0 insertions, 267 deletions
diff --git a/drivers/i2c/chips/ds1374.c b/drivers/i2c/chips/ds1374.c
deleted file mode 100644
index 8a2ff0c114d..00000000000
--- a/drivers/i2c/chips/ds1374.c
+++ /dev/null
@@ -1,267 +0,0 @@
-/*
- * drivers/i2c/chips/ds1374.c
- *
- * I2C client/driver for the Maxim/Dallas DS1374 Real-Time Clock
- *
- * Author: Randy Vinson <rvinson@mvista.com>
- *
- * Based on the m41t00.c by Mark Greer <mgreer@mvista.com>
- *
- * 2005 (c) MontaVista Software, Inc. This file is licensed under
- * the terms of the GNU General Public License version 2. This program
- * is licensed "as is" without any warranty of any kind, whether express
- * or implied.
- */
-/*
- * This i2c client/driver wedges between the drivers/char/genrtc.c RTC
- * interface and the SMBus interface of the i2c subsystem.
- * It would be more efficient to use i2c msgs/i2c_transfer directly but, as
- * recommened in .../Documentation/i2c/writing-clients section
- * "Sending and receiving", using SMBus level communication is preferred.
- */
-
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/interrupt.h>
-#include <linux/i2c.h>
-#include <linux/rtc.h>
-#include <linux/bcd.h>
-#include <linux/mutex.h>
-#include <linux/workqueue.h>
-
-#define DS1374_REG_TOD0 0x00
-#define DS1374_REG_TOD1 0x01
-#define DS1374_REG_TOD2 0x02
-#define DS1374_REG_TOD3 0x03
-#define DS1374_REG_WDALM0 0x04
-#define DS1374_REG_WDALM1 0x05
-#define DS1374_REG_WDALM2 0x06
-#define DS1374_REG_CR 0x07
-#define DS1374_REG_SR 0x08
-#define DS1374_REG_SR_OSF 0x80
-#define DS1374_REG_TCR 0x09
-
-#define DS1374_DRV_NAME "ds1374"
-
-static DEFINE_MUTEX(ds1374_mutex);
-
-static struct i2c_driver ds1374_driver;
-static struct i2c_client *save_client;
-
-static unsigned short ignore[] = { I2C_CLIENT_END };
-static unsigned short normal_addr[] = { 0x68, I2C_CLIENT_END };
-
-static struct i2c_client_address_data addr_data = {
- .normal_i2c = normal_addr,
- .probe = ignore,
- .ignore = ignore,
-};
-
-static ulong ds1374_read_rtc(void)
-{
- ulong time = 0;
- int reg = DS1374_REG_WDALM0;
-
- while (reg--) {
- s32 tmp;
- if ((tmp = i2c_smbus_read_byte_data(save_client, reg)) < 0) {
- dev_warn(&save_client->dev,
- "can't read from rtc chip\n");
- return 0;
- }
- time = (time << 8) | (tmp & 0xff);
- }
- return time;
-}
-
-static void ds1374_write_rtc(ulong time)
-{
- int reg;
-
- for (reg = DS1374_REG_TOD0; reg < DS1374_REG_WDALM0; reg++) {
- if (i2c_smbus_write_byte_data(save_client, reg, time & 0xff)
- < 0) {
- dev_warn(&save_client->dev,
- "can't write to rtc chip\n");
- break;
- }
- time = time >> 8;
- }
-}
-
-static void ds1374_check_rtc_status(void)
-{
- s32 tmp;
-
- tmp = i2c_smbus_read_byte_data(save_client, DS1374_REG_SR);
- if (tmp < 0) {
- dev_warn(&save_client->dev,
- "can't read status from rtc chip\n");
- return;
- }
- if (tmp & DS1374_REG_SR_OSF) {
- dev_warn(&save_client->dev,
- "oscillator discontinuity flagged, time unreliable\n");
- tmp &= ~DS1374_REG_SR_OSF;
- tmp = i2c_smbus_write_byte_data(save_client, DS1374_REG_SR,
- tmp & 0xff);
- if (tmp < 0)
- dev_warn(&save_client->dev,
- "can't clear discontinuity notification\n");
- }
-}
-
-ulong ds1374_get_rtc_time(void)
-{
- ulong t1, t2;
- int limit = 10; /* arbitrary retry limit */
-
- mutex_lock(&ds1374_mutex);
-
- /*
- * Since the reads are being performed one byte at a time using
- * the SMBus vs a 4-byte i2c transfer, there is a chance that a
- * carry will occur during the read. To detect this, 2 reads are
- * performed and compared.
- */
- do {
- t1 = ds1374_read_rtc();
- t2 = ds1374_read_rtc();
- } while (t1 != t2 && limit--);
-
- mutex_unlock(&ds1374_mutex);
-
- if (t1 != t2) {
- dev_warn(&save_client->dev,
- "can't get consistent time from rtc chip\n");
- t1 = 0;
- }
-
- return t1;
-}
-
-static ulong new_time;
-
-static void ds1374_set_work(struct work_struct *work)
-{
- ulong t1, t2;
- int limit = 10; /* arbitrary retry limit */
-
- t1 = new_time;
-
- mutex_lock(&ds1374_mutex);
-
- /*
- * Since the writes are being performed one byte at a time using
- * the SMBus vs a 4-byte i2c transfer, there is a chance that a
- * carry will occur during the write. To detect this, the write
- * value is read back and compared.
- */
- do {
- ds1374_write_rtc(t1);
- t2 = ds1374_read_rtc();
- } while (t1 != t2 && limit--);
-
- mutex_unlock(&ds1374_mutex);
-
- if (t1 != t2)
- dev_warn(&save_client->dev,
- "can't confirm time set from rtc chip\n");
-}
-
-static struct workqueue_struct *ds1374_workqueue;
-
-static DECLARE_WORK(ds1374_work, ds1374_set_work);
-
-int ds1374_set_rtc_time(ulong nowtime)
-{
- new_time = nowtime;
-
- if (in_interrupt())
- queue_work(ds1374_workqueue, &ds1374_work);
- else
- ds1374_set_work(NULL);
-
- return 0;
-}
-
-/*
- *****************************************************************************
- *
- * Driver Interface
- *
- *****************************************************************************
- */
-static int ds1374_probe(struct i2c_adapter *adap, int addr, int kind)
-{
- struct i2c_client *client;
- int rc;
-
- client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL);
- if (!client)
- return -ENOMEM;
-
- strncpy(client->name, DS1374_DRV_NAME, I2C_NAME_SIZE);
- client->addr = addr;
- client->adapter = adap;
- client->driver = &ds1374_driver;
-
- ds1374_workqueue = create_singlethread_workqueue("ds1374");
- if (!ds1374_workqueue) {
- kfree(client);
- return -ENOMEM; /* most expected reason */
- }
-
- if ((rc = i2c_attach_client(client)) != 0) {
- kfree(client);
- return rc;
- }
-
- save_client = client;
-
- ds1374_check_rtc_status();
-
- return 0;
-}
-
-static int ds1374_attach(struct i2c_adapter *adap)
-{
- return i2c_probe(adap, &addr_data, ds1374_probe);
-}
-
-static int ds1374_detach(struct i2c_client *client)
-{
- int rc;
-
- if ((rc = i2c_detach_client(client)) == 0) {
- kfree(i2c_get_clientdata(client));
- destroy_workqueue(ds1374_workqueue);
- }
- return rc;
-}
-
-static struct i2c_driver ds1374_driver = {
- .driver = {
- .name = DS1374_DRV_NAME,
- },
- .id = I2C_DRIVERID_DS1374,
- .attach_adapter = ds1374_attach,
- .detach_client = ds1374_detach,
-};
-
-static int __init ds1374_init(void)
-{
- return i2c_add_driver(&ds1374_driver);
-}
-
-static void __exit ds1374_exit(void)
-{
- i2c_del_driver(&ds1374_driver);
-}
-
-module_init(ds1374_init);
-module_exit(ds1374_exit);
-
-MODULE_AUTHOR("Randy Vinson <rvinson@mvista.com>");
-MODULE_DESCRIPTION("Maxim/Dallas DS1374 RTC I2C Client Driver");
-MODULE_LICENSE("GPL");
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-17 07:22:57 +0000