aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/i2c/algos/i2c-algo-sibyte.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/i2c/algos/i2c-algo-sibyte.c')
-rw-r--r--drivers/i2c/algos/i2c-algo-sibyte.c222
1 files changed, 222 insertions, 0 deletions
diff --git a/drivers/i2c/algos/i2c-algo-sibyte.c b/drivers/i2c/algos/i2c-algo-sibyte.c
new file mode 100644
index 000000000000..35789bb7126a
--- /dev/null
+++ b/drivers/i2c/algos/i2c-algo-sibyte.c
@@ -0,0 +1,222 @@
+/* ------------------------------------------------------------------------- */
+/* i2c-algo-sibyte.c i2c driver algorithms for bit-shift adapters */
+/* ------------------------------------------------------------------------- */
+/* Copyright (C) 2001,2002,2003 Broadcom Corporation
+ Copyright (C) 1995-2000 Simon G. Vogl
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+/* ------------------------------------------------------------------------- */
+
+/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and even
+ Frodo Looijaard <frodol@dds.nl>. */
+
+/* Ported for SiByte SOCs by Broadcom Corporation. */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+
+#include <asm/io.h>
+#include <asm/sibyte/sb1250_regs.h>
+#include <asm/sibyte/sb1250_smbus.h>
+
+#include <linux/i2c.h>
+#include <linux/i2c-algo-sibyte.h>
+
+/* ----- global defines ----------------------------------------------- */
+#define SMB_CSR(a,r) ((long)(a->reg_base + r))
+
+/* ----- global variables --------------------------------------------- */
+
+/* module parameters:
+ */
+static int bit_scan=0; /* have a look at what's hanging 'round */
+
+
+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 -1; /* XXXKW better error code? */
+ }
+
+ 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 -1; /* XXXKW better error code? */
+ }
+
+ 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 int algo_control(struct i2c_adapter *adapter,
+ unsigned int cmd, unsigned long arg)
+{
+ 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 struct i2c_algorithm i2c_sibyte_algo = {
+ .name = "SiByte algorithm",
+ .id = I2C_ALGO_SIBYTE,
+ .smbus_xfer = smbus_xfer,
+ .algo_control = algo_control, /* ioctl */
+ .functionality = bit_func,
+};
+
+/*
+ * registering functions to load algorithms at runtime
+ */
+int i2c_sibyte_add_bus(struct i2c_adapter *i2c_adap, int speed)
+{
+ int i;
+ struct i2c_algo_sibyte_data *adap = i2c_adap->algo_data;
+
+ /* register new adapter to i2c module... */
+
+ i2c_adap->id |= i2c_sibyte_algo.id;
+ i2c_adap->algo = &i2c_sibyte_algo;
+
+ /* Set the frequency to 100 kHz */
+ csr_out32(speed, SMB_CSR(adap,R_SMB_FREQ));
+ csr_out32(0, SMB_CSR(adap,R_SMB_CONTROL));
+
+ /* scan bus */
+ if (bit_scan) {
+ union i2c_smbus_data data;
+ int rc;
+ printk(KERN_INFO " i2c-algo-sibyte.o: scanning bus %s.\n",
+ i2c_adap->name);
+ for (i = 0x00; i < 0x7f; i++) {
+ /* XXXKW is this a realistic probe? */
+ rc = smbus_xfer(i2c_adap, i, 0, I2C_SMBUS_READ, 0,
+ I2C_SMBUS_BYTE_DATA, &data);
+ if (!rc) {
+ printk("(%02x)",i);
+ } else
+ printk(".");
+ }
+ printk("\n");
+ }
+
+ i2c_add_adapter(i2c_adap);
+
+ return 0;
+}
+
+
+int i2c_sibyte_del_bus(struct i2c_adapter *adap)
+{
+ int res;
+
+ if ((res = i2c_del_adapter(adap)) < 0)
+ return res;
+
+ return 0;
+}
+
+int __init i2c_algo_sibyte_init (void)
+{
+ printk("i2c-algo-sibyte.o: i2c SiByte algorithm module\n");
+ return 0;
+}
+
+
+EXPORT_SYMBOL(i2c_sibyte_add_bus);
+EXPORT_SYMBOL(i2c_sibyte_del_bus);
+
+#ifdef MODULE
+MODULE_AUTHOR("Kip Walker, Broadcom Corp.");
+MODULE_DESCRIPTION("SiByte I2C-Bus algorithm");
+MODULE_PARM(bit_scan, "i");
+MODULE_PARM_DESC(bit_scan, "Scan for active chips on the bus");
+MODULE_LICENSE("GPL");
+
+int init_module(void)
+{
+ return i2c_algo_sibyte_init();
+}
+
+void cleanup_module(void)
+{
+}
+#endif
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.