xref: /openbmc/u-boot/drivers/w1-eeprom/ds24xxx.c (revision 6f443330)
10749f646SMaxime Ripard // SPDX-License-Identifier:	GPL-2.0+
20749f646SMaxime Ripard /*
30749f646SMaxime Ripard  *
40749f646SMaxime Ripard  * Copyright (c) 2015 Free Electrons
50749f646SMaxime Ripard  * Copyright (c) 2015 NextThing Co
60749f646SMaxime Ripard  * Copyright (c) 2018 Microchip Technology, Inc.
70749f646SMaxime Ripard  *
80749f646SMaxime Ripard  */
90749f646SMaxime Ripard 
100749f646SMaxime Ripard #include <common.h>
110749f646SMaxime Ripard #include <linux/err.h>
120749f646SMaxime Ripard #include <dm.h>
130749f646SMaxime Ripard #include <w1-eeprom.h>
140749f646SMaxime Ripard #include <w1.h>
150749f646SMaxime Ripard 
160749f646SMaxime Ripard #define W1_F2D_READ_EEPROM	0xf0
170749f646SMaxime Ripard 
ds24xxx_read_buf(struct udevice * dev,unsigned int offset,u8 * buf,unsigned int count)180749f646SMaxime Ripard static int ds24xxx_read_buf(struct udevice *dev, unsigned int offset,
190749f646SMaxime Ripard 			    u8 *buf, unsigned int count)
200749f646SMaxime Ripard {
210749f646SMaxime Ripard 	w1_reset_select(dev);
220749f646SMaxime Ripard 
230749f646SMaxime Ripard 	w1_write_byte(dev, W1_F2D_READ_EEPROM);
240749f646SMaxime Ripard 	w1_write_byte(dev, offset & 0xff);
250749f646SMaxime Ripard 	w1_write_byte(dev, offset >> 8);
260749f646SMaxime Ripard 
270749f646SMaxime Ripard 	return w1_read_buf(dev, buf, count);
280749f646SMaxime Ripard }
290749f646SMaxime Ripard 
ds24xxx_probe(struct udevice * dev)300749f646SMaxime Ripard static int ds24xxx_probe(struct udevice *dev)
310749f646SMaxime Ripard {
320749f646SMaxime Ripard 	struct w1_device *w1;
330749f646SMaxime Ripard 
34*586d4b01SMartin Fuzzey 	w1 = dev_get_parent_platdata(dev);
350749f646SMaxime Ripard 	w1->id = 0;
360749f646SMaxime Ripard 	return 0;
370749f646SMaxime Ripard }
380749f646SMaxime Ripard 
390749f646SMaxime Ripard static const struct w1_eeprom_ops ds24xxx_ops = {
400749f646SMaxime Ripard 	.read_buf	= ds24xxx_read_buf,
410749f646SMaxime Ripard };
420749f646SMaxime Ripard 
430749f646SMaxime Ripard static const struct udevice_id ds24xxx_id[] = {
440749f646SMaxime Ripard 	{ .compatible = "maxim,ds24b33", .data = W1_FAMILY_DS24B33 },
450749f646SMaxime Ripard 	{ .compatible = "maxim,ds2431", .data = W1_FAMILY_DS2431 },
460749f646SMaxime Ripard 	{ },
470749f646SMaxime Ripard };
480749f646SMaxime Ripard 
490749f646SMaxime Ripard U_BOOT_DRIVER(ds24xxx) = {
500749f646SMaxime Ripard 	.name		= "ds24xxx",
510749f646SMaxime Ripard 	.id		= UCLASS_W1_EEPROM,
520749f646SMaxime Ripard 	.of_match	= ds24xxx_id,
530749f646SMaxime Ripard 	.ops		= &ds24xxx_ops,
540749f646SMaxime Ripard 	.probe		= ds24xxx_probe,
550749f646SMaxime Ripard };
56