1 // SPDX-License-Identifier: GPL-2.0-only
3  * Copyright (C) 2006-2007 PA Semi, Inc
5  * SMBus host driver for PA Semi PWRficient
18 #include "i2c-pasemi-core.h"
45 static inline void reg_write(struct pasemi_smbus *smbus, int reg, int val)  in reg_write()
47 	dev_dbg(smbus->dev, "smbus write reg %x val %08x\n", reg, val);  in reg_write()
48 	iowrite32(val, smbus->ioaddr + reg);  in reg_write()
51 static inline int reg_read(struct pasemi_smbus *smbus, int reg)  in reg_read()
54 	ret = ioread32(smbus->ioaddr + reg);  in reg_read()
55 	dev_dbg(smbus->dev, "smbus read reg %x val %08x\n", reg, ret);  in reg_read()
62 static void pasemi_reset(struct pasemi_smbus *smbus)  in pasemi_reset()
64 	u32 val = (CTL_MTR | CTL_MRR | (smbus->clk_div & CTL_CLK_M));  in pasemi_reset()
66 	if (smbus->hw_rev >= 6)  in pasemi_reset()
70 	reinit_completion(&smbus->irq_completion);  in pasemi_reset()
73 static void pasemi_smb_clear(struct pasemi_smbus *smbus)  in pasemi_smb_clear()
81 static int pasemi_smb_waitready(struct pasemi_smbus *smbus)  in pasemi_smb_waitready()
86 	if (smbus->use_irq) {  in pasemi_smb_waitready()
87 		reinit_completion(&smbus->irq_completion);  in pasemi_smb_waitready()
89 		wait_for_completion_timeout(&smbus->irq_completion, msecs_to_jiffies(100));  in pasemi_smb_waitready()
94 		while (!(status & SMSTA_XEN) && timeout--) {  in pasemi_smb_waitready()
102 		return -ENXIO;  in pasemi_smb_waitready()
105 		dev_warn(smbus->dev, "Timeout, status 0x%08x\n", status);  in pasemi_smb_waitready()
107 		return -ETIME;  in pasemi_smb_waitready()
116 static int pasemi_i2c_xfer_msg(struct i2c_adapter *adapter,  in pasemi_i2c_xfer_msg()
119 	struct pasemi_smbus *smbus = adapter->algo_data;  in pasemi_i2c_xfer_msg()
123 	read = msg->flags & I2C_M_RD ? 1 : 0;  in pasemi_i2c_xfer_msg()
128 		TXFIFO_WR(smbus, msg->len | MTXFIFO_READ |  in pasemi_i2c_xfer_msg()
135 		for (i = 0; i < msg->len; i++) {  in pasemi_i2c_xfer_msg()
138 				err = -ENODATA;  in pasemi_i2c_xfer_msg()
141 			msg->buf[i] = rd & MRXFIFO_DATA_M;  in pasemi_i2c_xfer_msg()
144 		for (i = 0; i < msg->len - 1; i++)  in pasemi_i2c_xfer_msg()
145 			TXFIFO_WR(smbus, msg->buf[i]);  in pasemi_i2c_xfer_msg()
147 		TXFIFO_WR(smbus, msg->buf[msg->len-1] |  in pasemi_i2c_xfer_msg()
164 static int pasemi_i2c_xfer(struct i2c_adapter *adapter,  in pasemi_i2c_xfer()
167 	struct pasemi_smbus *smbus = adapter->algo_data;  in pasemi_i2c_xfer()
175 		ret = pasemi_i2c_xfer_msg(adapter, &msgs[i], (i == (num - 1)));  in pasemi_i2c_xfer()
180 static int pasemi_smb_xfer(struct i2c_adapter *adapter,  in pasemi_smb_xfer()
184 	struct pasemi_smbus *smbus = adapter->algo_data;  in pasemi_smb_xfer()
189 	/* All our ops take 8-bit shifted addresses */  in pasemi_smb_xfer()
214 			TXFIFO_WR(smbus, MTXFIFO_STOP | data->byte);  in pasemi_smb_xfer()
224 			TXFIFO_WR(smbus, data->word & MTXFIFO_DATA_M);  in pasemi_smb_xfer()
225 			TXFIFO_WR(smbus, MTXFIFO_STOP | (data->word >> 8));  in pasemi_smb_xfer()
240 			len = min_t(u8, data->block[0], I2C_SMBUS_BLOCK_MAX);  in pasemi_smb_xfer()
243 				TXFIFO_WR(smbus, data->block[i]);  in pasemi_smb_xfer()
244 			TXFIFO_WR(smbus, data->block[len] | MTXFIFO_STOP);  in pasemi_smb_xfer()
251 		TXFIFO_WR(smbus, data->word & MTXFIFO_DATA_M);  in pasemi_smb_xfer()
252 		TXFIFO_WR(smbus, (data->word >> 8) & MTXFIFO_DATA_M);  in pasemi_smb_xfer()
257 		len = min_t(u8, data->block[0], I2C_SMBUS_BLOCK_MAX - 1);  in pasemi_smb_xfer()
263 			TXFIFO_WR(smbus, data->block[i]);  in pasemi_smb_xfer()
268 			    I2C_SMBUS_BLOCK_MAX - len);  in pasemi_smb_xfer()
273 		dev_warn(&adapter->dev, "Unsupported transaction %d\n", size);  in pasemi_smb_xfer()
274 		return -EINVAL;  in pasemi_smb_xfer()
289 			err = -ENODATA;  in pasemi_smb_xfer()
292 		data->byte = rd & MRXFIFO_DATA_M;  in pasemi_smb_xfer()
298 			err = -ENODATA;  in pasemi_smb_xfer()
301 		data->word = rd & MRXFIFO_DATA_M;  in pasemi_smb_xfer()
304 			err = -ENODATA;  in pasemi_smb_xfer()
307 		data->word |= (rd & MRXFIFO_DATA_M) << 8;  in pasemi_smb_xfer()
311 		data->block[0] = len;  in pasemi_smb_xfer()
315 				err = -ENODATA;  in pasemi_smb_xfer()
318 			data->block[i] = rd & MRXFIFO_DATA_M;  in pasemi_smb_xfer()
330 static u32 pasemi_smb_func(struct i2c_adapter *adapter)  in pasemi_smb_func()
338 static const struct i2c_algorithm smbus_algorithm = {
348 	smbus->adapter.owner = THIS_MODULE;  in pasemi_i2c_common_probe()
349 	snprintf(smbus->adapter.name, sizeof(smbus->adapter.name),  in pasemi_i2c_common_probe()
350 		 "PA Semi SMBus adapter (%s)", dev_name(smbus->dev));  in pasemi_i2c_common_probe()
351 	smbus->adapter.algo = &smbus_algorithm;  in pasemi_i2c_common_probe()
352 	smbus->adapter.algo_data = smbus;  in pasemi_i2c_common_probe()
355 	smbus->adapter.dev.parent = smbus->dev;  in pasemi_i2c_common_probe()
356 	smbus->use_irq = 0;  in pasemi_i2c_common_probe()
357 	init_completion(&smbus->irq_completion);  in pasemi_i2c_common_probe()
359 	if (smbus->hw_rev != PASEMI_HW_REV_PCI)  in pasemi_i2c_common_probe()
360 		smbus->hw_rev = reg_read(smbus, REG_REV);  in pasemi_i2c_common_probe()
366 	error = devm_i2c_add_adapter(smbus->dev, &smbus->adapter);  in pasemi_i2c_common_probe()
379 	complete(&smbus->irq_completion);  in pasemi_irq_handler()
386 MODULE_DESCRIPTION("PA Semi PWRficient SMBus driver");