[U-Boot] [PATCH 28/37] rtc: s35392a: encode command correctly

Robert Beckett
2019-10-15T15:53:41Z

From: Ian Ray <ian.ray@ge.com>

The 3-bit "command", or register, is encoded within the device address.
Configure the device accordingly, and pass command in DM I2C read/write
calls correctly.

Signed-off-by: Ian Ray <ian.ray@ge.com>
Signed-off-by: Robert Beckett <bob.beckett@collabora.com>
---
drivers/rtc/s35392a.c | 27 ++++++++++++++++-----------
1 file changed, 16 insertions(+), 11 deletions(-)

diff --git a/drivers/rtc/s35392a.c b/drivers/rtc/s35392a.c
index 844f1b72c7..53cd590e69 100644
--- a/drivers/rtc/s35392a.c
+++ b/drivers/rtc/s35392a.c
@@ -24,11 +24,13 @@
#include <linux/bitrev.h>
#include <rtc.h>

-#define S35390A_CMD_STATUS1 0x30
-#define S35390A_CMD_STATUS2 0x31
-#define S35390A_CMD_TIME1 0x32
-#define S35390A_CMD_TIME2 0x33
-#define S35390A_CMD_INT2_REG1 0x35
+#define S35390A_CHIP_ADDR 0x30
+
+#define S35390A_CMD_STATUS1 0x0
+#define S35390A_CMD_STATUS2 0x1
+#define S35390A_CMD_TIME1 0x2
+#define S35390A_CMD_TIME2 0x3
+#define S35390A_CMD_INT2_REG1 0x5

#define S35390A_BYTE_YEAR 0
#define S35390A_BYTE_MONTH 1
@@ -85,11 +87,10 @@ static int s35392a_rtc_read(DEV_TYPE *dev, u8 reg, u8 *buf, int len)
int ret;

#ifdef CONFIG_DM_RTC
- /* TODO: we need to tweak the chip address to reg */
- ret = dm_i2c_read(dev, 0, buf, len);
+ ret = dm_i2c_read(dev, reg, buf, len);
#else
(void)dev;
- ret = i2c_read(reg, 0, -1, buf, len);
+ ret = i2c_read(S35390A_CHIP_ADDR | reg, 0, -1, buf, len);
#endif

return ret;
@@ -100,11 +101,10 @@ static int s35392a_rtc_write(DEV_TYPE *dev, u8 reg, u8 *buf, int len)
int ret;

#ifdef CONFIG_DM_RTC
- /* TODO: we need to tweak the chip address to reg */
- ret = dm_i2c_write(dev, 0, buf, 1);
+ ret = dm_i2c_write(dev, reg, buf, len);
#else
(void)dev;
- ret = i2c_write(reg, 0, 0, buf, len);
+ ret = i2c_write(S35390A_CHIP_ADDR | reg, 0, 0, buf, len);
#endif

return ret;
@@ -336,6 +336,11 @@ void rtc_init(void)

static int s35392a_probe(struct udevice *dev)
{
+ /* 3-bit "command", or register, is encoded within the device address.
+ */
+ i2c_set_chip_offset_len(dev, 0);
+ i2c_set_chip_addr_offset_mask(dev, 0x7);
+
s35392a_rtc_init(dev);
return 0;
}
--
2.20.1