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Diffstat (limited to 'src/soc/intel/common/block/smbus')
-rw-r--r--src/soc/intel/common/block/smbus/smbus_early.c5
-rw-r--r--src/soc/intel/common/block/smbus/smbuslib.c41
-rw-r--r--src/soc/intel/common/block/smbus/smbuslib.h2
3 files changed, 48 insertions, 0 deletions
diff --git a/src/soc/intel/common/block/smbus/smbus_early.c b/src/soc/intel/common/block/smbus/smbus_early.c
index e0c4d9c649..9e6afc4563 100644
--- a/src/soc/intel/common/block/smbus/smbus_early.c
+++ b/src/soc/intel/common/block/smbus/smbus_early.c
@@ -36,6 +36,11 @@ static const struct reg_script smbus_init_script[] = {
REG_SCRIPT_END,
};
+u16 smbus_read_word(u32 smbus_dev, u8 addr, u8 offset)
+{
+ return smbus_read16(SMBUS_IO_BASE, addr, offset);
+}
+
u8 smbus_read_byte(u32 smbus_dev, u8 addr, u8 offset)
{
return smbus_read8(SMBUS_IO_BASE, addr, offset);
diff --git a/src/soc/intel/common/block/smbus/smbuslib.c b/src/soc/intel/common/block/smbus/smbuslib.c
index 27b4ad5c5d..0d3901fa2b 100644
--- a/src/soc/intel/common/block/smbus/smbuslib.c
+++ b/src/soc/intel/common/block/smbus/smbuslib.c
@@ -135,3 +135,44 @@ int smbus_write8(unsigned int smbus_base, unsigned int device,
return 0;
}
+
+int smbus_read16(unsigned int smbus_base, unsigned int device,
+ unsigned int address)
+{
+ unsigned char global_status_register;
+ unsigned short data;
+
+ if (smbus_wait_till_ready(smbus_base) < 0)
+ return SMBUS_WAIT_UNTIL_READY_TIMEOUT;
+
+ /* Set up transaction */
+ /* Disable interrupts */
+ outb(inb(smbus_base + SMBHSTCTL) & ~1, smbus_base + SMBHSTCTL);
+ /* Set the device I'm talking to */
+ outb(((device & 0x7f) << 1) | 1, smbus_base + SMBXMITADD);
+ /* Set the command/address... */
+ outb(address & 0xff, smbus_base + SMBHSTCMD);
+ /* Set up for a word data read */
+ outb((inb(smbus_base + SMBHSTCTL) & 0xe3) | (0x3 << 2),
+ (smbus_base + SMBHSTCTL));
+ /* Clear any lingering errors, so the transaction will run */
+ outb(inb(smbus_base + SMBHSTSTAT), smbus_base + SMBHSTSTAT);
+
+ /* Start the command */
+ outb((inb(smbus_base + SMBHSTCTL) | 0x40),
+ smbus_base + SMBHSTCTL);
+
+ /* Poll for transaction completion */
+ if (smbus_wait_till_done(smbus_base) < 0)
+ return SMBUS_WAIT_UNTIL_DONE_TIMEOUT;
+
+ global_status_register = inb(smbus_base + SMBHSTSTAT);
+ /* Ignore the "In Use" status... */
+ if ((global_status_register & ~(3 << 5)) != (1 << 1))
+ return SMBUS_ERROR;
+
+ /* Read results of transaction */
+ data = inw(smbus_base + SMBHSTDAT0);
+
+ return data;
+}
diff --git a/src/soc/intel/common/block/smbus/smbuslib.h b/src/soc/intel/common/block/smbus/smbuslib.h
index b5be6ca84e..05dafe9947 100644
--- a/src/soc/intel/common/block/smbus/smbuslib.h
+++ b/src/soc/intel/common/block/smbus/smbuslib.h
@@ -34,5 +34,7 @@ int smbus_read8(unsigned int smbus_base, unsigned int device,
unsigned int address);
int smbus_write8(unsigned int smbus_base, unsigned int device,
unsigned int address, unsigned int data);
+int smbus_read16(unsigned int smbus_base, unsigned int device,
+ unsigned int address);
#endif /* SOC_INTEL_COMMON_BLOCK_SMBUS__LIB_H */