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Diffstat (limited to 'qemu/roms/u-boot/drivers/hwmon/ds1775.c')
-rw-r--r--qemu/roms/u-boot/drivers/hwmon/ds1775.c126
1 files changed, 126 insertions, 0 deletions
diff --git a/qemu/roms/u-boot/drivers/hwmon/ds1775.c b/qemu/roms/u-boot/drivers/hwmon/ds1775.c
new file mode 100644
index 000000000..b95b130d9
--- /dev/null
+++ b/qemu/roms/u-boot/drivers/hwmon/ds1775.c
@@ -0,0 +1,126 @@
+/*
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/*
+ * Dallas Semiconductor's DS1775 Digital Thermometer and Thermostat
+ */
+
+#include <common.h>
+
+#include <i2c.h>
+#include <dtt.h>
+
+#define DTT_I2C_DEV_CODE CONFIG_SYS_I2C_DTT_ADDR /* Dallas Semi's DS1775 device code */
+#define DTT_READ_TEMP 0x0
+#define DTT_CONFIG 0x1
+#define DTT_TEMP_HYST 0x2
+#define DTT_TEMP_OS 0x3
+
+int dtt_read(int sensor, int reg)
+{
+ int dlen;
+ uchar data[2];
+
+ /*
+ * Calculate sensor address and command
+ */
+ sensor = DTT_I2C_DEV_CODE + (sensor & 0x07); /* Calculate addr of ds1775 */
+
+ /*
+ * Prepare to handle 2 byte result
+ */
+ if ((reg == DTT_READ_TEMP) ||
+ (reg == DTT_TEMP_OS) || (reg == DTT_TEMP_HYST))
+ dlen = 2;
+ else
+ dlen = 1;
+
+ /*
+ * Now try to read the register
+ */
+ if (i2c_read(sensor, reg, 1, data, dlen) != 0)
+ return 1;
+
+ /*
+ * Handle 2 byte result
+ */
+ if (dlen == 2)
+ return ((int)((short)data[1] + (((short)data[0]) << 8)));
+
+ return (int) data[0];
+}
+
+
+int dtt_write(int sensor, int reg, int val)
+{
+ int dlen;
+ uchar data[2];
+
+ /*
+ * Calculate sensor address and register
+ */
+ sensor = DTT_I2C_DEV_CODE + (sensor & 0x07);
+
+ /*
+ * Handle various data sizes
+ */
+ if ((reg == DTT_READ_TEMP) ||
+ (reg == DTT_TEMP_OS) || (reg == DTT_TEMP_HYST)) {
+ dlen = 2;
+ data[0] = (char)((val >> 8) & 0xff); /* MSB first */
+ data[1] = (char)(val & 0xff);
+ } else {
+ dlen = 1;
+ data[0] = (char)(val & 0xff);
+ }
+
+ /*
+ * Write value to device
+ */
+ if (i2c_write(sensor, reg, 1, data, dlen) != 0)
+ return 1;
+
+ return 0;
+}
+
+
+int dtt_init_one(int sensor)
+{
+ int val;
+
+ /*
+ * Setup High Temp
+ */
+ val = ((CONFIG_SYS_DTT_MAX_TEMP * 2) << 7) & 0xff80;
+ if (dtt_write(sensor, DTT_TEMP_OS, val) != 0)
+ return 1;
+ udelay(50000); /* Max 50ms */
+
+ /*
+ * Setup Low Temp - hysteresis
+ */
+ val = (((CONFIG_SYS_DTT_MAX_TEMP - CONFIG_SYS_DTT_HYSTERESIS) * 2) << 7) & 0xff80;
+ if (dtt_write(sensor, DTT_TEMP_HYST, val) != 0)
+ return 1;
+ udelay(50000); /* Max 50ms */
+
+ /*
+ * Setup configuraton register
+ *
+ * Fault Tolerance limits 4, Thermometer resolution bits is 9,
+ * Polarity = Active Low,continuous conversion mode, Thermostat
+ * mode is interrupt mode
+ */
+ val = 0xa;
+ if (dtt_write(sensor, DTT_CONFIG, val) != 0)
+ return 1;
+ udelay(50000); /* Max 50ms */
+
+ return 0;
+}
+
+int dtt_get_temp(int sensor)
+{
+ return (dtt_read(sensor, DTT_READ_TEMP) / 256);
+}