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Commit 5369c02d authored by Sreedhara DS's avatar Sreedhara DS Committed by Matthew Garrett
Browse files

intel_scu_ipc: Utility driver for intel scu ipc



This driver implements ioctl and interfaces with intel scu ipc driver. It
is used to access pmic/msic registers from user space and firmware update
utility.

Signed-off-by: default avatarSreedhara DS <sreedhara.ds@intel.com>
[Extensive clean up and debug]
Signed-off-by: default avatarAlan Cox <alan@linux.intel.com>
Signed-off-by: default avatarMatthew Garrett <mjg@redhat.com>
parent 3e5b08cb
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+9 −0
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@@ -576,6 +576,15 @@ config INTEL_SCU_IPC
	  some embedded Intel x86 platforms. This is not needed for PC-type
	  machines.

config INTEL_SCU_IPC_UTIL
	tristate "Intel SCU IPC utility driver"
	depends on INTEL_SCU_IPC
	default y
	---help---
	  The IPC Util driver provides an interface with the SCU enabling
	  low level access for debug work and updating the firmware. Say
	  N unless you will be doing this on an Intel MID platform.

config GPIO_INTEL_PMIC
	bool "Intel PMIC GPIO support"
	depends on INTEL_SCU_IPC && GPIOLIB
+1 −0
Original line number Diff line number Diff line
@@ -28,6 +28,7 @@ obj-$(CONFIG_TOPSTAR_LAPTOP) += topstar-laptop.o
obj-$(CONFIG_ACPI_TOSHIBA)	+= toshiba_acpi.o
obj-$(CONFIG_TOSHIBA_BT_RFKILL)	+= toshiba_bluetooth.o
obj-$(CONFIG_INTEL_SCU_IPC)	+= intel_scu_ipc.o
obj-$(CONFIG_INTEL_SCU_IPC_UTIL)+= intel_scu_ipcutil.o
obj-$(CONFIG_RAR_REGISTER)	+= intel_rar_register.o
obj-$(CONFIG_INTEL_IPS)		+= intel_ips.o
obj-$(CONFIG_GPIO_INTEL_PMIC)	+= intel_pmic_gpio.o
+2 −2
Original line number Diff line number Diff line
@@ -497,7 +497,7 @@ int intel_scu_ipc_i2c_cntrl(u32 addr, u32 *data)
			"intel_scu_ipc: I2C INVALID_CMD = 0x%x\n", cmd);

		mutex_unlock(&ipclock);
		return -1;
		return -EIO;
	}
	mutex_unlock(&ipclock);
	return 0;
@@ -642,7 +642,7 @@ int intel_scu_ipc_fw_update(u8 *buffer, u32 length)

	if (status == IPC_FW_UPDATE_SUCCESS)
		return 0;
	return -1;
	return -EIO;
}
EXPORT_SYMBOL(intel_scu_ipc_fw_update);

+133 −0
Original line number Diff line number Diff line
/*
 * 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>");