From c6f24f99cd70a383699bdb34ddd9e6e51c83304c Mon Sep 17 00:00:00 2001 From: Riku Voipio Date: Wed, 6 Dec 2006 20:39:13 -0800 Subject: [PATCH] rtc-rs5c372: change register reading method According to the datasheet rs5c372 supports three different methods for reading register values. Change from method #1 to method #3, since method #3 is the only one that works on Thecus N2100 board with this RTC. Signed-off-by: Riku Voipio Cc: Alessandro Zummo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/rtc/rtc-rs5c372.c | 84 +++++++++++++++++++++++++---------------------- 1 file changed, 44 insertions(+), 40 deletions(-) diff --git a/drivers/rtc/rtc-rs5c372.c b/drivers/rtc/rtc-rs5c372.c index 9e1bb3a72f7a..e2c7698fdba3 100644 --- a/drivers/rtc/rtc-rs5c372.c +++ b/drivers/rtc/rtc-rs5c372.c @@ -13,7 +13,7 @@ #include #include -#define DRV_VERSION "0.2" +#define DRV_VERSION "0.3" /* Addresses to scan */ static unsigned short normal_i2c[] = { /* 0x32,*/ I2C_CLIENT_END }; @@ -39,6 +39,14 @@ static int rs5c372_attach(struct i2c_adapter *adapter); static int rs5c372_detach(struct i2c_client *client); static int rs5c372_probe(struct i2c_adapter *adapter, int address, int kind); +struct rs5c372 { + u8 reg_addr; + u8 regs[17]; + struct i2c_msg msg[1]; + struct i2c_client client; + struct rtc_device *rtc; +}; + static struct i2c_driver rs5c372_driver = { .driver = { .name = "rs5c372", @@ -49,18 +57,16 @@ static struct i2c_driver rs5c372_driver = { static int rs5c372_get_datetime(struct i2c_client *client, struct rtc_time *tm) { - unsigned char buf[7] = { RS5C372_REG_BASE }; - /* this implements the 1st reading method, according - * to the datasheet. buf[0] is initialized with - * address ptr and transmission format register. + struct rs5c372 *rs5c372 = i2c_get_clientdata(client); + u8 *buf = &(rs5c372->regs[1]); + + /* this implements the 3rd reading method, according + * to the datasheet. rs5c372 defaults to internal + * address 0xF, so 0x0 is in regs[1] */ - struct i2c_msg msgs[] = { - { client->addr, 0, 1, buf }, - { client->addr, I2C_M_RD, 7, buf }, - }; - if ((i2c_transfer(client->adapter, msgs, 2)) != 2) { + if ((i2c_transfer(client->adapter, rs5c372->msg, 1)) != 1) { dev_err(&client->dev, "%s: read error\n", __FUNCTION__); return -EIO; } @@ -114,23 +120,14 @@ static int rs5c372_set_datetime(struct i2c_client *client, struct rtc_time *tm) static int rs5c372_get_trim(struct i2c_client *client, int *osc, int *trim) { - unsigned char buf = RS5C372_REG_TRIM; - - struct i2c_msg msgs[] = { - { client->addr, 0, 1, &buf }, - { client->addr, I2C_M_RD, 1, &buf }, - }; - - if ((i2c_transfer(client->adapter, msgs, 2)) != 2) { - dev_err(&client->dev, "%s: read error\n", __FUNCTION__); - return -EIO; - } + struct rs5c372 *rs5c372 = i2c_get_clientdata(client); + u8 tmp = rs5c372->regs[RS5C372_REG_TRIM + 1]; if (osc) - *osc = (buf & RS5C372_TRIM_XSL) ? 32000 : 32768; + *osc = (tmp & RS5C372_TRIM_XSL) ? 32000 : 32768; if (trim) { - *trim = buf & RS5C372_TRIM_MASK; + *trim = tmp & RS5C372_TRIM_MASK; dev_dbg(&client->dev, "%s: raw trim=%x\n", __FUNCTION__, *trim); } @@ -201,7 +198,7 @@ static int rs5c372_probe(struct i2c_adapter *adapter, int address, int kind) { int err = 0; struct i2c_client *client; - struct rtc_device *rtc; + struct rs5c372 *rs5c372; dev_dbg(&adapter->dev, "%s\n", __FUNCTION__); @@ -210,10 +207,11 @@ static int rs5c372_probe(struct i2c_adapter *adapter, int address, int kind) goto exit; } - if (!(client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL))) { + if (!(rs5c372 = kzalloc(sizeof(struct rs5c372), GFP_KERNEL))) { err = -ENOMEM; goto exit; } + client = &rs5c372->client; /* I2C client */ client->addr = address; @@ -222,26 +220,33 @@ static int rs5c372_probe(struct i2c_adapter *adapter, int address, int kind) strlcpy(client->name, rs5c372_driver.driver.name, I2C_NAME_SIZE); + i2c_set_clientdata(client, rs5c372); + + rs5c372->msg[0].addr = address; + rs5c372->msg[0].flags = I2C_M_RD; + rs5c372->msg[0].len = sizeof(rs5c372->regs); + rs5c372->msg[0].buf = rs5c372->regs; + /* Inform the i2c layer */ if ((err = i2c_attach_client(client))) goto exit_kfree; dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n"); - rtc = rtc_device_register(rs5c372_driver.driver.name, &client->dev, - &rs5c372_rtc_ops, THIS_MODULE); + rs5c372->rtc = rtc_device_register(rs5c372_driver.driver.name, + &client->dev, &rs5c372_rtc_ops, THIS_MODULE); - if (IS_ERR(rtc)) { - err = PTR_ERR(rtc); + if (IS_ERR(rs5c372->rtc)) { + err = PTR_ERR(rs5c372->rtc); goto exit_detach; } - i2c_set_clientdata(client, rtc); - err = device_create_file(&client->dev, &dev_attr_trim); - if (err) goto exit_devreg; + if (err) + goto exit_devreg; err = device_create_file(&client->dev, &dev_attr_osc); - if (err) goto exit_trim; + if (err) + goto exit_trim; return 0; @@ -249,13 +254,13 @@ exit_trim: device_remove_file(&client->dev, &dev_attr_trim); exit_devreg: - rtc_device_unregister(rtc); + rtc_device_unregister(rs5c372->rtc); exit_detach: i2c_detach_client(client); exit_kfree: - kfree(client); + kfree(rs5c372); exit: return err; @@ -264,16 +269,15 @@ exit: static int rs5c372_detach(struct i2c_client *client) { int err; - struct rtc_device *rtc = i2c_get_clientdata(client); + struct rs5c372 *rs5c372 = i2c_get_clientdata(client); - if (rtc) - rtc_device_unregister(rtc); + if (rs5c372->rtc) + rtc_device_unregister(rs5c372->rtc); if ((err = i2c_detach_client(client))) return err; - kfree(client); - + kfree(rs5c372); return 0; } -- cgit v1.2.3