pmic:i2c: Handle PMIC I2C transmission comprising of two bytes
[platform/kernel/u-boot.git] / drivers / misc / pmic_i2c.c
1 /*
2  * Copyright (C) 2011 Samsung Electronics
3  * Lukasz Majewski <l.majewski@samsung.com>
4  *
5  * (C) Copyright 2010
6  * Stefano Babic, DENX Software Engineering, sbabic@denx.de
7  *
8  * (C) Copyright 2008-2009 Freescale Semiconductor, Inc.
9  *
10  * See file CREDITS for list of people who contributed to this
11  * project.
12  *
13  * This program is free software; you can redistribute it and/or
14  * modify it under the terms of the GNU General Public License as
15  * published by the Free Software Foundation; either version 2 of
16  * the License, or (at your option) any later version.
17  *
18  * This program is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21  * GNU General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with this program; if not, write to the Free Software
25  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
26  * MA 02111-1307 USA
27  */
28
29 #include <common.h>
30 #include <linux/types.h>
31 #include <pmic.h>
32 #include <i2c.h>
33
34 int pmic_reg_write(struct pmic *p, u32 reg, u32 val)
35 {
36         unsigned char buf[4] = { 0 };
37
38         if (check_reg(reg))
39                 return -1;
40
41         switch (pmic_i2c_tx_num) {
42         case 3:
43                 buf[0] = (val >> 16) & 0xff;
44                 buf[1] = (val >> 8) & 0xff;
45                 buf[2] = val & 0xff;
46                 break;
47         case 2:
48                 buf[0] = (val >> 8) & 0xff;
49                 buf[1] = val & 0xff;
50                 break;
51         case 1:
52                 buf[0] = val & 0xff;
53                 break;
54         default:
55                 printf("%s: invalid tx_num: %d", __func__, pmic_i2c_tx_num);
56                 return -1;
57         }
58
59         if (i2c_write(pmic_i2c_addr, reg, 1, buf, pmic_i2c_tx_num))
60                 return -1;
61
62         return 0;
63 }
64
65 int pmic_reg_read(struct pmic *p, u32 reg, u32 *val)
66 {
67         unsigned char buf[4] = { 0 };
68         u32 ret_val = 0;
69
70         if (check_reg(reg))
71                 return -1;
72
73         if (i2c_read(pmic_i2c_addr, reg, 1, buf, pmic_i2c_tx_num))
74                 return -1;
75
76         switch (pmic_i2c_tx_num) {
77         case 3:
78                 ret_val = buf[0] << 16 | buf[1] << 8 | buf[2];
79                 break;
80         case 2:
81                 ret_val = buf[0] << 8 | buf[1];
82                 break;
83         case 1:
84                 ret_val = buf[0];
85                 break;
86         default:
87                 printf("%s: invalid tx_num: %d", __func__, pmic_i2c_tx_num);
88                 return -1;
89         }
90         memcpy(val, &ret_val, sizeof(ret_val));
91
92         return 0;
93 }
94
95 int pmic_probe(struct pmic *p)
96 {
97         I2C_SET_BUS(p->bus);
98         debug("Bus: %d PMIC:%s probed!\n", p->bus, p->name);
99         if (i2c_probe(pmic_i2c_addr)) {
100                 printf("Can't find PMIC:%s\n", p->name);
101                 return -1;
102         }
103
104         return 0;
105 }