i2c/busses/i2c-keba.c

1 // SPDX-License-Identifier: GPL-2.0
14 #define KI2C "i2c-keba"
77 	ret = readb_poll_timeout(ki2c->base + KI2C_STATUS_REG,  in ki2c_inuse_lock()
81 		dev_err(&ki2c->auxdev->auxdev.dev, "%s err!\n", __func__);  in ki2c_inuse_lock()
89 	iowrite8(KI2C_STATUS_IN_USE, ki2c->base + KI2C_STATUS_REG);  in ki2c_inuse_unlock()
102 	return ki2c_wait_for_bit(ki2c->base + KI2C_STATUS_REG, KI2C_STATUS_MCF,  in ki2c_wait_for_mcf()
103 				 ki2c->adapter.timeout);  in ki2c_wait_for_mcf()
114 	return ki2c_wait_for_bit(ki2c->base + KI2C_STATUS_REG,  in ki2c_wait_for_data()
116 				 ki2c->adapter.timeout);  in ki2c_wait_for_data()
129 	reg = ioread8(ki2c->base + KI2C_STATUS_REG);  in ki2c_wait_for_data_ack()
131 		return -EIO;  in ki2c_wait_for_data_ack()
138 	unsigned int reg = ioread8(ki2c->base + KI2C_CAPABILITY_REG);  in ki2c_has_capability()
145 	unsigned int reg = ioread8(ki2c->base + KI2C_STATUS_DC_REG);  in ki2c_get_scl()
153 	unsigned int reg = ioread8(ki2c->base + KI2C_STATUS_DC_REG);  in ki2c_get_sda()
164 	control_dc = ioread8(ki2c->base + KI2C_CONTROL_DC_REG);  in ki2c_set_scl()
169 	iowrite8(control_dc, ki2c->base + KI2C_CONTROL_DC_REG);  in ki2c_set_scl()
173  * Resetting bus bitwise is done by checking SDA and applying clock cycles as
174  * long as SDA is low. 9 clock cycles are applied at most.
176  * Clock cycles are generated and udelay() determines the duration of clock
177  * cycles. Generated clock rate is 100 KHz and so duration of both clock levels
178  * is: delay in ns = (10^6 / 100) / 2
189 	iowrite8(0, ki2c->base + KI2C_CONTROL_REG);  in ki2c_reset_bus_bitwise()
191 	/* generate clock cycles */  in ki2c_reset_bus_bitwise()
198 				dev_err(&ki2c->auxdev->auxdev.dev,  in ki2c_reset_bus_bitwise()
200 				ret = -EBUSY;  in ki2c_reset_bus_bitwise()
215 		dev_err(&ki2c->auxdev->auxdev.dev, "SDA is still low!\n");  in ki2c_reset_bus_bitwise()
216 		ret = -EBUSY;  in ki2c_reset_bus_bitwise()
220 	iowrite8(KI2C_CONTROL_MEN, ki2c->base + KI2C_CONTROL_REG);  in ki2c_reset_bus_bitwise()
231  * the bus. The reason is, that after the 9 clock cycles the EEPROM will be in
241 	/* hold data line high for 9 clock cycles */  in ki2c_reset_bus_bytewise()
242 	iowrite8(0xFF, ki2c->base + KI2C_DATA_REG);  in ki2c_reset_bus_bytewise()
246 		 ki2c->base + KI2C_CONTROL_REG);  in ki2c_reset_bus_bytewise()
249 		dev_err(&ki2c->auxdev->auxdev.dev, "Start condition failed\n");  in ki2c_reset_bus_bytewise()
256 		 ki2c->base + KI2C_CONTROL_REG);  in ki2c_reset_bus_bytewise()
259 		dev_err(&ki2c->auxdev->auxdev.dev, "Stop condition failed\n");  in ki2c_reset_bus_bytewise()
290 	addr = m->addr << 1;  in ki2c_write_target_addr()
292 	if (m->flags & I2C_M_RD)  in ki2c_write_target_addr()
295 	iowrite8(addr, ki2c->base + KI2C_DATA_REG);  in ki2c_write_target_addr()
310 		 ki2c->base + KI2C_CONTROL_REG);  in ki2c_start_addr()
314 		 ki2c->base + KI2C_CONTROL_REG);  in ki2c_start_addr()
322 		dev_dbg(&ki2c->auxdev->auxdev.dev,  in ki2c_start_addr()
323 			"%s wait for ACK err at 0x%02x!\n", __func__, m->addr);  in ki2c_start_addr()
333 	if ((m->flags & I2C_M_RD) == 0) {  in ki2c_repstart_addr()
334 		dev_err(&ki2c->auxdev->auxdev.dev,  in ki2c_repstart_addr()
336 		return -EINVAL;  in ki2c_repstart_addr()
341 		 ki2c->base + KI2C_CONTROL_REG);  in ki2c_repstart_addr()
345 		dev_err(&ki2c->auxdev->auxdev.dev,  in ki2c_repstart_addr()
346 			"%s wait for MCF err at 0x%02x!\n", __func__, m->addr);  in ki2c_repstart_addr()
350 	/* write target-address byte */  in ki2c_repstart_addr()
355 		dev_err(&ki2c->auxdev->auxdev.dev,  in ki2c_repstart_addr()
356 			"%s wait for ACK err at 0x%02x!\n", __func__, m->addr);  in ki2c_repstart_addr()
363 	iowrite8(KI2C_CONTROL_MEN, ki2c->base + KI2C_CONTROL_REG);  in ki2c_stop()
374 		iowrite8(data[i], ki2c->base + KI2C_DATA_REG);  in ki2c_write()
395 	/* if just one byte => send tx-nack after transfer */  in ki2c_read()
399 	iowrite8(control, ki2c->base + KI2C_CONTROL_REG);  in ki2c_read()
402 	ioread8(ki2c->base + KI2C_DATA_REG);  in ki2c_read()
409 		if (i == len - 2)  in ki2c_read()
410 			/* send tx-nack after transfer of last byte */  in ki2c_read()
412 				 ki2c->base + KI2C_CONTROL_REG);  in ki2c_read()
413 		else if (i == len - 1)  in ki2c_read()
419 				 ki2c->base + KI2C_CONTROL_REG);  in ki2c_read()
422 		data[i] = ioread8(ki2c->base + KI2C_DATA_REG);  in ki2c_read()
448 		if (m->flags & I2C_M_RD)  in ki2c_xfer()
449 			ret = ki2c_read(ki2c, m->buf, m->len);  in ki2c_xfer()
451 			ret = ki2c_write(ki2c, m->buf, m->len);  in ki2c_xfer()
467 	for (i = 0; i < ki2c->client_size; i++) {  in ki2c_unregister_devices()
468 		struct i2c_client *client = ki2c->client[i];  in ki2c_unregister_devices()
477 	struct i2c_board_info *info = ki2c->auxdev->info;  in ki2c_register_devices()
481 	for (i = 0; i < ki2c->client_size; i++) {  in ki2c_register_devices()
486 		client = i2c_new_scanned_device(&ki2c->adapter, &info[i],  in ki2c_register_devices()
489 			ki2c->client[i] = client;  in ki2c_register_devices()
490 		} else if (PTR_ERR(client) != -ENODEV) {  in ki2c_register_devices()
491 			ki2c->client_size = i;  in ki2c_register_devices()
514 	struct device *dev = &auxdev->dev;  in ki2c_probe()
521 		return -ENOMEM;  in ki2c_probe()
522 	ki2c->auxdev = container_of(auxdev, struct keba_i2c_auxdev, auxdev);  in ki2c_probe()
523 	ki2c->client = devm_kcalloc(dev, ki2c->auxdev->info_size,  in ki2c_probe()
524 				    sizeof(*ki2c->client), GFP_KERNEL);  in ki2c_probe()
525 	if (!ki2c->client)  in ki2c_probe()
526 		return -ENOMEM;  in ki2c_probe()
527 	ki2c->client_size = ki2c->auxdev->info_size;  in ki2c_probe()
530 	ki2c->base = devm_ioremap_resource(dev, &ki2c->auxdev->io);  in ki2c_probe()
531 	if (IS_ERR(ki2c->base))  in ki2c_probe()
532 		return PTR_ERR(ki2c->base);  in ki2c_probe()
534 	adap = &ki2c->adapter;  in ki2c_probe()
535 	strscpy(adap->name, "KEBA I2C adapter", sizeof(adap->name));  in ki2c_probe()
536 	adap->owner = THIS_MODULE;  in ki2c_probe()
537 	adap->class = I2C_CLASS_HWMON;  in ki2c_probe()
538 	adap->algo = &ki2c_algo;  in ki2c_probe()
539 	adap->dev.parent = dev;  in ki2c_probe()
544 	iowrite8(KI2C_CONTROL_MEN, ki2c->base + KI2C_CONTROL_REG);  in ki2c_probe()
566 	iowrite8(KI2C_CONTROL_DISABLE, ki2c->base + KI2C_CONTROL_REG);  in ki2c_probe()
577 	iowrite8(KI2C_CONTROL_DISABLE, ki2c->base + KI2C_CONTROL_REG);  in ki2c_remove()