linux-imx

// SPDX-License-Identifier: GPL-2.0

​

#include <linux/device.h>

#include <linux/err.h>

#include <linux/errno.h>

#include <linux/fs.h>

#include <linux/fsi-sbefifo.h>

#include <linux/gfp.h>

#include <linux/idr.h>

#include <linux/kernel.h>

#include <linux/list.h>

#include <linux/miscdevice.h>

#include <linux/module.h>

#include <linux/mutex.h>

#include <linux/fsi-occ.h>

#include <linux/of.h>

#include <linux/platform_device.h>

#include <linux/sched.h>

#include <linux/slab.h>

#include <linux/uaccess.h>

#include <asm/unaligned.h>

​

#define OCC_SRAM_BYTES      4096

#define OCC_CMD_DATA_BYTES  4090

#define OCC_RESP_DATA_BYTES 4089

​

#define OCC_SRAM_CMD_ADDR   0xFFFBE000

#define OCC_SRAM_RSP_ADDR   0xFFFBF000

​

/*

 * Assume we don't have much FFDC, if we do we'll overflow and

 * fail the command. This needs to be big enough for simple

 * commands as well.

 */

#define OCC_SBE_STATUS_WORDS    32

​

#define OCC_TIMEOUT_MS      1000

#define OCC_CMD_IN_PRG_WAIT_MS  50

​

struct occ {

    struct device *dev;

    struct device *sbefifo;

    char name[32];

    int idx;

    struct miscdevice mdev;

    struct mutex occ_lock;

};

​

#define to_occ(x)   container_of((x), struct occ, mdev)

​

struct occ_response {

    u8 seq_no;

    u8 cmd_type;

    u8 return_status;

    __be16 data_length;

    u8 data[OCC_RESP_DATA_BYTES + 2];   /* two bytes checksum */

} __packed;

​

struct occ_client {

    struct occ *occ;

    struct mutex lock;

    size_t data_size;

    size_t read_offset;

    u8 *buffer;

};

​

#define to_client(x)    container_of((x), struct occ_client, xfr)

​

static DEFINE_IDA(occ_ida);

​

static int occ_open(struct inode *inode, struct file *file)

{

    struct occ_client *client = kzalloc(sizeof(*client), GFP_KERNEL);

    struct miscdevice *mdev = file->private_data;

    struct occ *occ = to_occ(mdev);

​

    if (!client)

        return -ENOMEM;

​

    client->buffer = (u8 *)__get_free_page(GFP_KERNEL);

    if (!client->buffer) {

        kfree(client);

        return -ENOMEM;

    }

​

    client->occ = occ;

    mutex_init(&client->lock);

    file->private_data = client;

​

    /* We allocate a 1-page buffer, make sure it all fits */

    BUILD_BUG_ON((OCC_CMD_DATA_BYTES + 3) > PAGE_SIZE);

    BUILD_BUG_ON((OCC_RESP_DATA_BYTES + 7) > PAGE_SIZE);