v4.19.13 snapshot.
diff --git a/include/linux/i2c-algo-pca.h b/include/linux/i2c-algo-pca.h
new file mode 100644
index 0000000..d030717
--- /dev/null
+++ b/include/linux/i2c-algo-pca.h
@@ -0,0 +1,72 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_I2C_ALGO_PCA_H
+#define _LINUX_I2C_ALGO_PCA_H
+
+/* Chips known to the pca algo */
+#define I2C_PCA_CHIP_9564 0x00
+#define I2C_PCA_CHIP_9665 0x01
+
+/* Internal period for PCA9665 oscilator */
+#define I2C_PCA_OSC_PER 3 /* e10-8s */
+
+/* Clock speeds for the bus for PCA9564*/
+#define I2C_PCA_CON_330kHz 0x00
+#define I2C_PCA_CON_288kHz 0x01
+#define I2C_PCA_CON_217kHz 0x02
+#define I2C_PCA_CON_146kHz 0x03
+#define I2C_PCA_CON_88kHz 0x04
+#define I2C_PCA_CON_59kHz 0x05
+#define I2C_PCA_CON_44kHz 0x06
+#define I2C_PCA_CON_36kHz 0x07
+
+/* PCA9564 registers */
+#define I2C_PCA_STA 0x00 /* STATUS Read Only */
+#define I2C_PCA_TO 0x00 /* TIMEOUT Write Only */
+#define I2C_PCA_DAT 0x01 /* DATA Read/Write */
+#define I2C_PCA_ADR 0x02 /* OWN ADR Read/Write */
+#define I2C_PCA_CON 0x03 /* CONTROL Read/Write */
+
+/* PCA9665 registers */
+#define I2C_PCA_INDPTR 0x00 /* INDIRECT Pointer Write Only */
+#define I2C_PCA_IND 0x02 /* INDIRECT Read/Write */
+
+/* PCA9665 indirect registers */
+#define I2C_PCA_ICOUNT 0x00 /* Byte Count for buffered mode */
+#define I2C_PCA_IADR 0x01 /* OWN ADR */
+#define I2C_PCA_ISCLL 0x02 /* SCL LOW period */
+#define I2C_PCA_ISCLH 0x03 /* SCL HIGH period */
+#define I2C_PCA_ITO 0x04 /* TIMEOUT */
+#define I2C_PCA_IPRESET 0x05 /* Parallel bus reset */
+#define I2C_PCA_IMODE 0x06 /* I2C Bus mode */
+
+/* PCA9665 I2C bus mode */
+#define I2C_PCA_MODE_STD 0x00 /* Standard mode */
+#define I2C_PCA_MODE_FAST 0x01 /* Fast mode */
+#define I2C_PCA_MODE_FASTP 0x02 /* Fast Plus mode */
+#define I2C_PCA_MODE_TURBO 0x03 /* Turbo mode */
+
+
+#define I2C_PCA_CON_AA 0x80 /* Assert Acknowledge */
+#define I2C_PCA_CON_ENSIO 0x40 /* Enable */
+#define I2C_PCA_CON_STA 0x20 /* Start */
+#define I2C_PCA_CON_STO 0x10 /* Stop */
+#define I2C_PCA_CON_SI 0x08 /* Serial Interrupt */
+#define I2C_PCA_CON_CR 0x07 /* Clock Rate (MASK) */
+
+struct i2c_algo_pca_data {
+ void *data; /* private low level data */
+ void (*write_byte) (void *data, int reg, int val);
+ int (*read_byte) (void *data, int reg);
+ int (*wait_for_completion) (void *data);
+ void (*reset_chip) (void *data);
+ /* For PCA9564, use one of the predefined frequencies:
+ * 330000, 288000, 217000, 146000, 88000, 59000, 44000, 36000
+ * For PCA9665, use the frequency you want here. */
+ unsigned int i2c_clock;
+ unsigned int chip;
+};
+
+int i2c_pca_add_bus(struct i2c_adapter *);
+int i2c_pca_add_numbered_bus(struct i2c_adapter *);
+
+#endif /* _LINUX_I2C_ALGO_PCA_H */