| /* |
| * Copyright (c) 2013 Intel Corporation. All Rights Reserved. |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License version |
| * 2 as published by the Free Software Foundation. |
| * |
| * 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., 51 Franklin Street, Fifth Floor, Boston, MA |
| * 02110-1301, USA. |
| * |
| */ |
| #include <linux/bitops.h> |
| #include <linux/device.h> |
| #include <linux/errno.h> |
| #include <linux/fs.h> |
| #include <linux/init.h> |
| #include <linux/i2c.h> |
| #include <linux/io.h> |
| #include <linux/kernel.h> |
| #include <linux/mm.h> |
| #include <linux/slab.h> |
| #include <linux/string.h> |
| #include <linux/types.h> |
| #include <media/v4l2-device.h> |
| #include "common.h" |
| |
| /* |
| * Read EEPROM data from the gerneral e2prom chip(eg. |
| * CAT24C08, CAT24C128, le24l042cs, and store |
| * it into a kmalloced buffer. On error return NULL. |
| * @size: set to the size of the returned EEPROM data. |
| */ |
| void *e2prom_otp_read(struct v4l2_subdev *sd, u8 dev_addr, |
| u32 start_addr, u32 size) |
| { |
| struct i2c_client *client = v4l2_get_subdevdata(sd); |
| unsigned int e2prom_i2c_addr = dev_addr >> 1; |
| static const unsigned int max_read_size = 30; |
| int addr; |
| u32 s_addr = start_addr & E2PROM_ADDR_MASK; |
| bool two_addr = (start_addr & E2PROM_2ADDR) >> 31; |
| char *buffer; |
| |
| buffer = devm_kzalloc(&client->dev, size, GFP_KERNEL); |
| if (!buffer) |
| return NULL; |
| |
| for (addr = s_addr; addr < size; addr += max_read_size) { |
| struct i2c_msg msg[2]; |
| unsigned int i2c_addr = e2prom_i2c_addr; |
| u16 addr_buf; |
| int r; |
| |
| msg[0].flags = 0; |
| if (two_addr) { |
| msg[0].addr = i2c_addr; |
| addr_buf = cpu_to_be16(addr & 0xFFFF); |
| msg[0].len = 2; |
| msg[0].buf = (u8 *)&addr_buf; |
| } else { |
| i2c_addr |= (addr >> 8) & 0x7; |
| msg[0].addr = i2c_addr; |
| addr_buf = addr & 0xFF; |
| msg[0].len = 1; |
| msg[0].buf = (u8 *)&addr_buf; |
| } |
| |
| msg[1].addr = i2c_addr; |
| msg[1].flags = I2C_M_RD; |
| msg[1].len = min(max_read_size, size - addr); |
| msg[1].buf = &buffer[addr]; |
| |
| r = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg)); |
| if (r != ARRAY_SIZE(msg)) { |
| dev_err(&client->dev, "read failed at 0x%03x\n", addr); |
| return NULL; |
| } |
| } |
| return buffer; |
| } |
| |
| |