diff options
Diffstat (limited to 'drivers/staging/media/atomisp/i2c/atomisp-libmsrlisthelper.c')
| -rw-r--r-- | drivers/staging/media/atomisp/i2c/atomisp-libmsrlisthelper.c | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/drivers/staging/media/atomisp/i2c/atomisp-libmsrlisthelper.c b/drivers/staging/media/atomisp/i2c/atomisp-libmsrlisthelper.c new file mode 100644 index 000000000000..81e5ec0c2b64 --- /dev/null +++ b/drivers/staging/media/atomisp/i2c/atomisp-libmsrlisthelper.c @@ -0,0 +1,205 @@ +/* + * 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. + * + * + */ +#include <linux/i2c.h> +#include <linux/firmware.h> +#include <linux/device.h> +#include <linux/export.h> +#include "../include/linux/libmsrlisthelper.h" +#include <linux/module.h> +#include <linux/slab.h> + +/* Tagged binary data container structure definitions. */ +struct tbd_header { + uint32_t tag; /*!< Tag identifier, also checks endianness */ + uint32_t size; /*!< Container size including this header */ + uint32_t version; /*!< Version, format 0xYYMMDDVV */ + uint32_t revision; /*!< Revision, format 0xYYMMDDVV */ + uint32_t config_bits; /*!< Configuration flag bits set */ + uint32_t checksum; /*!< Global checksum, header included */ +} __packed; + +struct tbd_record_header { + uint32_t size; /*!< Size of record including header */ + uint8_t format_id; /*!< tbd_format_t enumeration values used */ + uint8_t packing_key; /*!< Packing method; 0 = no packing */ + uint16_t class_id; /*!< tbd_class_t enumeration values used */ +} __packed; + +struct tbd_data_record_header { + uint16_t next_offset; + uint16_t flags; + uint16_t data_offset; + uint16_t data_size; +} __packed; + +#define TBD_CLASS_DRV_ID 2 + +static int set_msr_configuration(struct i2c_client *client, uint8_t *bufptr, + unsigned int size) +{ + /* The configuration data contains any number of sequences where + * the first byte (that is, uint8_t) that marks the number of bytes + * in the sequence to follow, is indeed followed by the indicated + * number of bytes of actual data to be written to sensor. + * By convention, the first two bytes of actual data should be + * understood as an address in the sensor address space (hibyte + * followed by lobyte) where the remaining data in the sequence + * will be written. */ + + uint8_t *ptr = bufptr; + while (ptr < bufptr + size) { + struct i2c_msg msg = { + .addr = client->addr, + .flags = 0, + }; + int ret; + + /* How many bytes */ + msg.len = *ptr++; + /* Where the bytes are located */ + msg.buf = ptr; + ptr += msg.len; + + if (ptr > bufptr + size) + /* Accessing data beyond bounds is not tolerated */ + return -EINVAL; + + ret = i2c_transfer(client->adapter, &msg, 1); + if (ret < 0) { + dev_err(&client->dev, "i2c write error: %d", ret); + return ret; + } + } + return 0; +} + +static int parse_and_apply(struct i2c_client *client, uint8_t *buffer, + unsigned int size) +{ + uint8_t *endptr8 = buffer + size; + struct tbd_data_record_header *header = + (struct tbd_data_record_header *)buffer; + + /* There may be any number of datasets present */ + unsigned int dataset = 0; + + do { + /* In below, four variables are read from buffer */ + if ((uint8_t *)header + sizeof(*header) > endptr8) + return -EINVAL; + + /* All data should be located within given buffer */ + if ((uint8_t *)header + header->data_offset + + header->data_size > endptr8) + return -EINVAL; + + /* We have a new valid dataset */ + dataset++; + /* See whether there is MSR data */ + /* If yes, update the reg info */ + if (header->data_size && (header->flags & 1)) { + int ret; + + dev_info(&client->dev, + "New MSR data for sensor driver (dataset %02d) size:%d\n", + dataset, header->data_size); + ret = set_msr_configuration(client, + buffer + header->data_offset, + header->data_size); + if (ret) + return ret; + } + header = (struct tbd_data_record_header *)(buffer + + header->next_offset); + } while (header->next_offset); + + return 0; +} + +int apply_msr_data(struct i2c_client *client, const struct firmware *fw) +{ + struct tbd_header *header; + struct tbd_record_header *record; + + if (!fw) { + dev_warn(&client->dev, "Drv data is not loaded.\n"); + return -EINVAL; + } + + if (sizeof(*header) > fw->size) + return -EINVAL; + + header = (struct tbd_header *)fw->data; + /* Check that we have drvb block. */ + if (memcmp(&header->tag, "DRVB", 4)) + return -EINVAL; + + /* Check the size */ + if (header->size != fw->size) + return -EINVAL; + + if (sizeof(*header) + sizeof(*record) > fw->size) + return -EINVAL; + + record = (struct tbd_record_header *)(header + 1); + /* Check that class id mathes tbd's drv id. */ + if (record->class_id != TBD_CLASS_DRV_ID) + return -EINVAL; + + /* Size 0 shall not be treated as an error */ + if (!record->size) + return 0; + + return parse_and_apply(client, (uint8_t *)(record + 1), record->size); +} +EXPORT_SYMBOL_GPL(apply_msr_data); + +int load_msr_list(struct i2c_client *client, char *name, + const struct firmware **fw) +{ + int ret = request_firmware(fw, name, &client->dev); + if (ret) { + dev_err(&client->dev, + "Error %d while requesting firmware %s\n", + ret, name); + return ret; + } + dev_info(&client->dev, "Received %lu bytes drv data\n", + (unsigned long)(*fw)->size); + + return 0; +} +EXPORT_SYMBOL_GPL(load_msr_list); + +void release_msr_list(struct i2c_client *client, const struct firmware *fw) +{ + release_firmware(fw); +} +EXPORT_SYMBOL_GPL(release_msr_list); + +static int init_msrlisthelper(void) +{ + return 0; +} + +static void exit_msrlisthelper(void) +{ +} + +module_init(init_msrlisthelper); +module_exit(exit_msrlisthelper); + +MODULE_AUTHOR("Jukka Kaartinen <jukka.o.kaartinen@intel.com>"); +MODULE_LICENSE("GPL"); |