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Diffstat (limited to 'drivers/i2c/busses/i2c-sibyte.c')
-rw-r--r--drivers/i2c/busses/i2c-sibyte.c186
1 files changed, 186 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-sibyte.c b/drivers/i2c/busses/i2c-sibyte.c
new file mode 100644
index 000000000..8f71f01cb
--- /dev/null
+++ b/drivers/i2c/busses/i2c-sibyte.c
@@ -0,0 +1,186 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2004 Steven J. Hill
+ * Copyright (C) 2001,2002,2003 Broadcom Corporation
+ * Copyright (C) 1995-2000 Simon G. Vogl
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/io.h>
+#include <asm/sibyte/sb1250_regs.h>
+#include <asm/sibyte/sb1250_smbus.h>
+
+
+struct i2c_algo_sibyte_data {
+ void *data; /* private data */
+ int bus; /* which bus */
+ void *reg_base; /* CSR base */
+};
+
+/* ----- global defines ----------------------------------------------- */
+#define SMB_CSR(a,r) ((long)(a->reg_base + r))
+
+
+static int smbus_xfer(struct i2c_adapter *i2c_adap, u16 addr,
+ unsigned short flags, char read_write,
+ u8 command, int size, union i2c_smbus_data * data)
+{
+ struct i2c_algo_sibyte_data *adap = i2c_adap->algo_data;
+ int data_bytes = 0;
+ int error;
+
+ while (csr_in32(SMB_CSR(adap, R_SMB_STATUS)) & M_SMB_BUSY)
+ ;
+
+ switch (size) {
+ case I2C_SMBUS_QUICK:
+ csr_out32((V_SMB_ADDR(addr) |
+ (read_write == I2C_SMBUS_READ ? M_SMB_QDATA : 0) |
+ V_SMB_TT_QUICKCMD), SMB_CSR(adap, R_SMB_START));
+ break;
+ case I2C_SMBUS_BYTE:
+ if (read_write == I2C_SMBUS_READ) {
+ csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_RD1BYTE),
+ SMB_CSR(adap, R_SMB_START));
+ data_bytes = 1;
+ } else {
+ csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD));
+ csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR1BYTE),
+ SMB_CSR(adap, R_SMB_START));
+ }
+ break;
+ case I2C_SMBUS_BYTE_DATA:
+ csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD));
+ if (read_write == I2C_SMBUS_READ) {
+ csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_CMD_RD1BYTE),
+ SMB_CSR(adap, R_SMB_START));
+ data_bytes = 1;
+ } else {
+ csr_out32(V_SMB_LB(data->byte),
+ SMB_CSR(adap, R_SMB_DATA));
+ csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR2BYTE),
+ SMB_CSR(adap, R_SMB_START));
+ }
+ break;
+ case I2C_SMBUS_WORD_DATA:
+ csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD));
+ if (read_write == I2C_SMBUS_READ) {
+ csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_CMD_RD2BYTE),
+ SMB_CSR(adap, R_SMB_START));
+ data_bytes = 2;
+ } else {
+ csr_out32(V_SMB_LB(data->word & 0xff),
+ SMB_CSR(adap, R_SMB_DATA));
+ csr_out32(V_SMB_MB(data->word >> 8),
+ SMB_CSR(adap, R_SMB_DATA));
+ csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR2BYTE),
+ SMB_CSR(adap, R_SMB_START));
+ }
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ while (csr_in32(SMB_CSR(adap, R_SMB_STATUS)) & M_SMB_BUSY)
+ ;
+
+ error = csr_in32(SMB_CSR(adap, R_SMB_STATUS));
+ if (error & M_SMB_ERROR) {
+ /* Clear error bit by writing a 1 */
+ csr_out32(M_SMB_ERROR, SMB_CSR(adap, R_SMB_STATUS));
+ return (error & M_SMB_ERROR_TYPE) ? -EIO : -ENXIO;
+ }
+
+ if (data_bytes == 1)
+ data->byte = csr_in32(SMB_CSR(adap, R_SMB_DATA)) & 0xff;
+ if (data_bytes == 2)
+ data->word = csr_in32(SMB_CSR(adap, R_SMB_DATA)) & 0xffff;
+
+ return 0;
+}
+
+static u32 bit_func(struct i2c_adapter *adap)
+{
+ return (I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
+ I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA);
+}
+
+
+/* -----exported algorithm data: ------------------------------------- */
+
+static const struct i2c_algorithm i2c_sibyte_algo = {
+ .smbus_xfer = smbus_xfer,
+ .functionality = bit_func,
+};
+
+/*
+ * registering functions to load algorithms at runtime
+ */
+static int __init i2c_sibyte_add_bus(struct i2c_adapter *i2c_adap, int speed)
+{
+ struct i2c_algo_sibyte_data *adap = i2c_adap->algo_data;
+
+ /* Register new adapter to i2c module... */
+ i2c_adap->algo = &i2c_sibyte_algo;
+
+ /* Set the requested frequency. */
+ csr_out32(speed, SMB_CSR(adap,R_SMB_FREQ));
+ csr_out32(0, SMB_CSR(adap,R_SMB_CONTROL));
+
+ return i2c_add_numbered_adapter(i2c_adap);
+}
+
+
+static struct i2c_algo_sibyte_data sibyte_board_data[2] = {
+ { NULL, 0, (void *) (CKSEG1+A_SMB_BASE(0)) },
+ { NULL, 1, (void *) (CKSEG1+A_SMB_BASE(1)) }
+};
+
+static struct i2c_adapter sibyte_board_adapter[2] = {
+ {
+ .owner = THIS_MODULE,
+ .class = I2C_CLASS_HWMON | I2C_CLASS_SPD,
+ .algo = NULL,
+ .algo_data = &sibyte_board_data[0],
+ .nr = 0,
+ .name = "SiByte SMBus 0",
+ },
+ {
+ .owner = THIS_MODULE,
+ .class = I2C_CLASS_HWMON | I2C_CLASS_SPD,
+ .algo = NULL,
+ .algo_data = &sibyte_board_data[1],
+ .nr = 1,
+ .name = "SiByte SMBus 1",
+ },
+};
+
+static int __init i2c_sibyte_init(void)
+{
+ pr_info("i2c-sibyte: i2c SMBus adapter module for SiByte board\n");
+ if (i2c_sibyte_add_bus(&sibyte_board_adapter[0], K_SMB_FREQ_100KHZ) < 0)
+ return -ENODEV;
+ if (i2c_sibyte_add_bus(&sibyte_board_adapter[1],
+ K_SMB_FREQ_400KHZ) < 0) {
+ i2c_del_adapter(&sibyte_board_adapter[0]);
+ return -ENODEV;
+ }
+ return 0;
+}
+
+static void __exit i2c_sibyte_exit(void)
+{
+ i2c_del_adapter(&sibyte_board_adapter[0]);
+ i2c_del_adapter(&sibyte_board_adapter[1]);
+}
+
+module_init(i2c_sibyte_init);
+module_exit(i2c_sibyte_exit);
+
+MODULE_AUTHOR("Kip Walker (Broadcom Corp.)");
+MODULE_AUTHOR("Steven J. Hill <sjhill@realitydiluted.com>");
+MODULE_DESCRIPTION("SMBus adapter routines for SiByte boards");
+MODULE_LICENSE("GPL");