diff options
Diffstat (limited to 'drivers/platform/x86/intel_scu_ipcutil.c')
| -rw-r--r-- | drivers/platform/x86/intel_scu_ipcutil.c | 133 | 
1 files changed, 133 insertions, 0 deletions
diff --git a/drivers/platform/x86/intel_scu_ipcutil.c b/drivers/platform/x86/intel_scu_ipcutil.c new file mode 100644 index 00000000000..ba3231d0819 --- /dev/null +++ b/drivers/platform/x86/intel_scu_ipcutil.c @@ -0,0 +1,133 @@ +/* + * intel_scu_ipc.c: Driver for the Intel SCU IPC mechanism + * + * (C) Copyright 2008-2010 Intel Corporation + * Author: Sreedhara DS (sreedhara.ds@intel.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; version 2 + * of the License. + * + * This driver provides ioctl interfaces to call intel scu ipc driver api + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/fs.h> +#include <linux/fcntl.h> +#include <linux/sched.h> +#include <linux/uaccess.h> +#include <linux/slab.h> +#include <linux/init.h> +#include <asm/intel_scu_ipc.h> + +static u32 major; + +#define MAX_FW_SIZE 264192 + +/* ioctl commnds */ +#define	INTE_SCU_IPC_REGISTER_READ	0 +#define INTE_SCU_IPC_REGISTER_WRITE	1 +#define INTE_SCU_IPC_REGISTER_UPDATE	2 +#define INTE_SCU_IPC_FW_UPDATE		0xA2 + +struct scu_ipc_data { +	u32     count;  /* No. of registers */ +	u16     addr[5]; /* Register addresses */ +	u8      data[5]; /* Register data */ +	u8      mask; /* Valid for read-modify-write */ +}; + +/** + *	scu_reg_access		-	implement register access ioctls + *	@cmd: command we are doing (read/write/update) + *	@data: kernel copy of ioctl data + * + *	Allow the user to perform register accesses on the SCU via the + *	kernel interface + */ + +static int scu_reg_access(u32 cmd, struct scu_ipc_data  *data) +{ +	int count = data->count; + +	if (count == 0 || count == 3 || count > 4) +		return -EINVAL; + +	switch (cmd) { +	case INTE_SCU_IPC_REGISTER_READ: +		return intel_scu_ipc_readv(data->addr, data->data, count); +	case INTE_SCU_IPC_REGISTER_WRITE: +		return intel_scu_ipc_writev(data->addr, data->data, count); +	case INTE_SCU_IPC_REGISTER_UPDATE: +		return intel_scu_ipc_update_register(data->addr[0], +						    data->data[0], data->mask); +	default: +		return -ENOTTY; +	} +} + +/** + *	scu_ipc_ioctl		-	control ioctls for the SCU + *	@fp: file handle of the SCU device + *	@cmd: ioctl coce + *	@arg: pointer to user passed structure + * + *	Support the I/O and firmware flashing interfaces of the SCU + */ +static long scu_ipc_ioctl(struct file *fp, unsigned int cmd, +							unsigned long arg) +{ +	int ret; +	struct scu_ipc_data  data; +	void __user *argp = (void __user *)arg; + +	if (!capable(CAP_SYS_RAWIO)) +		return -EPERM; + +	if (cmd == INTE_SCU_IPC_FW_UPDATE) { +			u8 *fwbuf = kmalloc(MAX_FW_SIZE, GFP_KERNEL); +			if (fwbuf == NULL) +				return -ENOMEM; +			if (copy_from_user(fwbuf, (u8 *)arg, MAX_FW_SIZE)) { +				kfree(fwbuf); +				return -EFAULT; +			} +			ret = intel_scu_ipc_fw_update(fwbuf, MAX_FW_SIZE); +			kfree(fwbuf); +			return ret; +	} else { +		if (copy_from_user(&data, argp, sizeof(struct scu_ipc_data))) +			return -EFAULT; +		ret = scu_reg_access(cmd, &data); +		if (ret < 0) +			return ret; +		if (copy_to_user(argp, &data, sizeof(struct scu_ipc_data))) +			return -EFAULT; +		return 0; +	} +} + +static const struct file_operations scu_ipc_fops = { +	.unlocked_ioctl = scu_ipc_ioctl, +}; + +static int __init ipc_module_init(void) +{ +	return register_chrdev(0, "intel_mid_scu", &scu_ipc_fops); +} + +static void __exit ipc_module_exit(void) +{ +	unregister_chrdev(major, "intel_mid_scu"); +} + +module_init(ipc_module_init); +module_exit(ipc_module_exit); + +MODULE_LICENSE("GPL V2"); +MODULE_DESCRIPTION("Utility driver for intel scu ipc"); +MODULE_AUTHOR("Sreedhara <sreedhara.ds@intel.com>");  | 
