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e3d7fbab06
Omit an extra message for a memory allocation failure in this function. This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
802 lines
19 KiB
C
802 lines
19 KiB
C
/*
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* HSI character device driver, implements the character device
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* interface.
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*
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* Copyright (C) 2010 Nokia Corporation. All rights reserved.
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*
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* Contact: Andras Domokos <andras.domokos@nokia.com>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* version 2 as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
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* 02110-1301 USA
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*/
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#include <linux/errno.h>
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#include <linux/types.h>
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#include <linux/atomic.h>
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#include <linux/kernel.h>
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#include <linux/init.h>
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#include <linux/module.h>
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#include <linux/mutex.h>
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#include <linux/list.h>
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#include <linux/slab.h>
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#include <linux/kmemleak.h>
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#include <linux/ioctl.h>
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#include <linux/wait.h>
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#include <linux/fs.h>
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#include <linux/sched.h>
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#include <linux/device.h>
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#include <linux/cdev.h>
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#include <linux/uaccess.h>
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#include <linux/scatterlist.h>
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#include <linux/stat.h>
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#include <linux/hsi/hsi.h>
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#include <linux/hsi/hsi_char.h>
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#define HSC_DEVS 16 /* Num of channels */
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#define HSC_MSGS 4
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#define HSC_RXBREAK 0
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#define HSC_ID_BITS 6
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#define HSC_PORT_ID_BITS 4
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#define HSC_ID_MASK 3
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#define HSC_PORT_ID_MASK 3
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#define HSC_CH_MASK 0xf
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/*
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* We support up to 4 controllers that can have up to 4
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* ports, which should currently be more than enough.
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*/
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#define HSC_BASEMINOR(id, port_id) \
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((((id) & HSC_ID_MASK) << HSC_ID_BITS) | \
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(((port_id) & HSC_PORT_ID_MASK) << HSC_PORT_ID_BITS))
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enum {
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HSC_CH_OPEN,
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HSC_CH_READ,
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HSC_CH_WRITE,
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HSC_CH_WLINE,
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};
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enum {
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HSC_RX,
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HSC_TX,
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};
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struct hsc_client_data;
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/**
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* struct hsc_channel - hsi_char internal channel data
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* @ch: channel number
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* @flags: Keeps state of the channel (open/close, reading, writing)
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* @free_msgs_list: List of free HSI messages/requests
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* @rx_msgs_queue: List of pending RX requests
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* @tx_msgs_queue: List of pending TX requests
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* @lock: Serialize access to the lists
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* @cl: reference to the associated hsi_client
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* @cl_data: reference to the client data that this channels belongs to
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* @rx_wait: RX requests wait queue
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* @tx_wait: TX requests wait queue
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*/
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struct hsc_channel {
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unsigned int ch;
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unsigned long flags;
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struct list_head free_msgs_list;
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struct list_head rx_msgs_queue;
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struct list_head tx_msgs_queue;
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spinlock_t lock;
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struct hsi_client *cl;
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struct hsc_client_data *cl_data;
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wait_queue_head_t rx_wait;
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wait_queue_head_t tx_wait;
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};
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/**
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* struct hsc_client_data - hsi_char internal client data
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* @cdev: Characther device associated to the hsi_client
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* @lock: Lock to serialize open/close access
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* @flags: Keeps track of port state (rx hwbreak armed)
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* @usecnt: Use count for claiming the HSI port (mutex protected)
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* @cl: Referece to the HSI client
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* @channels: Array of channels accessible by the client
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*/
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struct hsc_client_data {
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struct cdev cdev;
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struct mutex lock;
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unsigned long flags;
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unsigned int usecnt;
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struct hsi_client *cl;
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struct hsc_channel channels[HSC_DEVS];
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};
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/* Stores the major number dynamically allocated for hsi_char */
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static unsigned int hsc_major;
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/* Maximum buffer size that hsi_char will accept from userspace */
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static unsigned int max_data_size = 0x1000;
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module_param(max_data_size, uint, 0);
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MODULE_PARM_DESC(max_data_size, "max read/write data size [4,8..65536] (^2)");
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static void hsc_add_tail(struct hsc_channel *channel, struct hsi_msg *msg,
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struct list_head *queue)
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{
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unsigned long flags;
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spin_lock_irqsave(&channel->lock, flags);
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list_add_tail(&msg->link, queue);
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spin_unlock_irqrestore(&channel->lock, flags);
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}
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static struct hsi_msg *hsc_get_first_msg(struct hsc_channel *channel,
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struct list_head *queue)
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{
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struct hsi_msg *msg = NULL;
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unsigned long flags;
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spin_lock_irqsave(&channel->lock, flags);
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if (list_empty(queue))
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goto out;
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msg = list_first_entry(queue, struct hsi_msg, link);
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list_del(&msg->link);
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out:
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spin_unlock_irqrestore(&channel->lock, flags);
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return msg;
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}
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static inline void hsc_msg_free(struct hsi_msg *msg)
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{
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kfree(sg_virt(msg->sgt.sgl));
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hsi_free_msg(msg);
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}
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static void hsc_free_list(struct list_head *list)
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{
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struct hsi_msg *msg, *tmp;
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list_for_each_entry_safe(msg, tmp, list, link) {
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list_del(&msg->link);
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hsc_msg_free(msg);
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}
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}
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static void hsc_reset_list(struct hsc_channel *channel, struct list_head *l)
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{
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unsigned long flags;
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LIST_HEAD(list);
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spin_lock_irqsave(&channel->lock, flags);
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list_splice_init(l, &list);
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spin_unlock_irqrestore(&channel->lock, flags);
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hsc_free_list(&list);
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}
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static inline struct hsi_msg *hsc_msg_alloc(unsigned int alloc_size)
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{
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struct hsi_msg *msg;
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void *buf;
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msg = hsi_alloc_msg(1, GFP_KERNEL);
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if (!msg)
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goto out;
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buf = kmalloc(alloc_size, GFP_KERNEL);
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if (!buf) {
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hsi_free_msg(msg);
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goto out;
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}
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sg_init_one(msg->sgt.sgl, buf, alloc_size);
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/* Ignore false positive, due to sg pointer handling */
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kmemleak_ignore(buf);
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return msg;
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out:
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return NULL;
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}
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static inline int hsc_msgs_alloc(struct hsc_channel *channel)
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{
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struct hsi_msg *msg;
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int i;
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for (i = 0; i < HSC_MSGS; i++) {
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msg = hsc_msg_alloc(max_data_size);
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if (!msg)
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goto out;
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msg->channel = channel->ch;
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list_add_tail(&msg->link, &channel->free_msgs_list);
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}
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return 0;
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out:
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hsc_free_list(&channel->free_msgs_list);
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return -ENOMEM;
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}
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static inline unsigned int hsc_msg_len_get(struct hsi_msg *msg)
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{
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return msg->sgt.sgl->length;
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}
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static inline void hsc_msg_len_set(struct hsi_msg *msg, unsigned int len)
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{
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msg->sgt.sgl->length = len;
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}
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static void hsc_rx_completed(struct hsi_msg *msg)
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{
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struct hsc_client_data *cl_data = hsi_client_drvdata(msg->cl);
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struct hsc_channel *channel = cl_data->channels + msg->channel;
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if (test_bit(HSC_CH_READ, &channel->flags)) {
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hsc_add_tail(channel, msg, &channel->rx_msgs_queue);
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wake_up(&channel->rx_wait);
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} else {
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hsc_add_tail(channel, msg, &channel->free_msgs_list);
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}
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}
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static void hsc_rx_msg_destructor(struct hsi_msg *msg)
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{
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msg->status = HSI_STATUS_ERROR;
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hsc_msg_len_set(msg, 0);
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hsc_rx_completed(msg);
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}
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static void hsc_tx_completed(struct hsi_msg *msg)
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{
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struct hsc_client_data *cl_data = hsi_client_drvdata(msg->cl);
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struct hsc_channel *channel = cl_data->channels + msg->channel;
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if (test_bit(HSC_CH_WRITE, &channel->flags)) {
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hsc_add_tail(channel, msg, &channel->tx_msgs_queue);
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wake_up(&channel->tx_wait);
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} else {
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hsc_add_tail(channel, msg, &channel->free_msgs_list);
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}
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}
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static void hsc_tx_msg_destructor(struct hsi_msg *msg)
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{
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msg->status = HSI_STATUS_ERROR;
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hsc_msg_len_set(msg, 0);
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hsc_tx_completed(msg);
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}
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static void hsc_break_req_destructor(struct hsi_msg *msg)
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{
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struct hsc_client_data *cl_data = hsi_client_drvdata(msg->cl);
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hsi_free_msg(msg);
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clear_bit(HSC_RXBREAK, &cl_data->flags);
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}
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static void hsc_break_received(struct hsi_msg *msg)
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{
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struct hsc_client_data *cl_data = hsi_client_drvdata(msg->cl);
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struct hsc_channel *channel = cl_data->channels;
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int i, ret;
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/* Broadcast HWBREAK on all channels */
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for (i = 0; i < HSC_DEVS; i++, channel++) {
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struct hsi_msg *msg2;
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if (!test_bit(HSC_CH_READ, &channel->flags))
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continue;
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msg2 = hsc_get_first_msg(channel, &channel->free_msgs_list);
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if (!msg2)
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continue;
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clear_bit(HSC_CH_READ, &channel->flags);
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hsc_msg_len_set(msg2, 0);
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msg2->status = HSI_STATUS_COMPLETED;
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hsc_add_tail(channel, msg2, &channel->rx_msgs_queue);
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wake_up(&channel->rx_wait);
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}
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hsi_flush(msg->cl);
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ret = hsi_async_read(msg->cl, msg);
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if (ret < 0)
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hsc_break_req_destructor(msg);
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}
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static int hsc_break_request(struct hsi_client *cl)
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{
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struct hsc_client_data *cl_data = hsi_client_drvdata(cl);
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struct hsi_msg *msg;
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int ret;
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if (test_and_set_bit(HSC_RXBREAK, &cl_data->flags))
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return -EBUSY;
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msg = hsi_alloc_msg(0, GFP_KERNEL);
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if (!msg) {
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clear_bit(HSC_RXBREAK, &cl_data->flags);
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return -ENOMEM;
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}
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msg->break_frame = 1;
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msg->complete = hsc_break_received;
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msg->destructor = hsc_break_req_destructor;
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ret = hsi_async_read(cl, msg);
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if (ret < 0)
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hsc_break_req_destructor(msg);
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return ret;
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}
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static int hsc_break_send(struct hsi_client *cl)
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{
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struct hsi_msg *msg;
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int ret;
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msg = hsi_alloc_msg(0, GFP_ATOMIC);
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if (!msg)
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return -ENOMEM;
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msg->break_frame = 1;
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msg->complete = hsi_free_msg;
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msg->destructor = hsi_free_msg;
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ret = hsi_async_write(cl, msg);
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if (ret < 0)
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hsi_free_msg(msg);
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return ret;
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}
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static int hsc_rx_set(struct hsi_client *cl, struct hsc_rx_config *rxc)
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{
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struct hsi_config tmp;
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int ret;
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if ((rxc->mode != HSI_MODE_STREAM) && (rxc->mode != HSI_MODE_FRAME))
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return -EINVAL;
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if ((rxc->channels == 0) || (rxc->channels > HSC_DEVS))
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return -EINVAL;
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if (rxc->channels & (rxc->channels - 1))
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return -EINVAL;
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if ((rxc->flow != HSI_FLOW_SYNC) && (rxc->flow != HSI_FLOW_PIPE))
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return -EINVAL;
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tmp = cl->rx_cfg;
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cl->rx_cfg.mode = rxc->mode;
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cl->rx_cfg.num_hw_channels = rxc->channels;
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cl->rx_cfg.flow = rxc->flow;
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ret = hsi_setup(cl);
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if (ret < 0) {
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cl->rx_cfg = tmp;
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return ret;
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}
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if (rxc->mode == HSI_MODE_FRAME)
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hsc_break_request(cl);
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return ret;
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}
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static inline void hsc_rx_get(struct hsi_client *cl, struct hsc_rx_config *rxc)
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{
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rxc->mode = cl->rx_cfg.mode;
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rxc->channels = cl->rx_cfg.num_hw_channels;
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rxc->flow = cl->rx_cfg.flow;
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}
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static int hsc_tx_set(struct hsi_client *cl, struct hsc_tx_config *txc)
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{
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struct hsi_config tmp;
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int ret;
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if ((txc->mode != HSI_MODE_STREAM) && (txc->mode != HSI_MODE_FRAME))
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return -EINVAL;
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if ((txc->channels == 0) || (txc->channels > HSC_DEVS))
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return -EINVAL;
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if (txc->channels & (txc->channels - 1))
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return -EINVAL;
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if ((txc->arb_mode != HSI_ARB_RR) && (txc->arb_mode != HSI_ARB_PRIO))
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return -EINVAL;
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tmp = cl->tx_cfg;
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cl->tx_cfg.mode = txc->mode;
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cl->tx_cfg.num_hw_channels = txc->channels;
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cl->tx_cfg.speed = txc->speed;
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cl->tx_cfg.arb_mode = txc->arb_mode;
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ret = hsi_setup(cl);
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if (ret < 0) {
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cl->tx_cfg = tmp;
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return ret;
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}
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return ret;
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}
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static inline void hsc_tx_get(struct hsi_client *cl, struct hsc_tx_config *txc)
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{
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txc->mode = cl->tx_cfg.mode;
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txc->channels = cl->tx_cfg.num_hw_channels;
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txc->speed = cl->tx_cfg.speed;
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txc->arb_mode = cl->tx_cfg.arb_mode;
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}
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static ssize_t hsc_read(struct file *file, char __user *buf, size_t len,
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loff_t *ppos __maybe_unused)
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{
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struct hsc_channel *channel = file->private_data;
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struct hsi_msg *msg;
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ssize_t ret;
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if (len == 0)
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return 0;
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if (!IS_ALIGNED(len, sizeof(u32)))
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return -EINVAL;
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if (len > max_data_size)
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len = max_data_size;
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if (channel->ch >= channel->cl->rx_cfg.num_hw_channels)
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return -ECHRNG;
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if (test_and_set_bit(HSC_CH_READ, &channel->flags))
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return -EBUSY;
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msg = hsc_get_first_msg(channel, &channel->free_msgs_list);
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if (!msg) {
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ret = -ENOSPC;
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goto out;
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}
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hsc_msg_len_set(msg, len);
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msg->complete = hsc_rx_completed;
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msg->destructor = hsc_rx_msg_destructor;
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ret = hsi_async_read(channel->cl, msg);
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if (ret < 0) {
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hsc_add_tail(channel, msg, &channel->free_msgs_list);
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goto out;
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}
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ret = wait_event_interruptible(channel->rx_wait,
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!list_empty(&channel->rx_msgs_queue));
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if (ret < 0) {
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clear_bit(HSC_CH_READ, &channel->flags);
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hsi_flush(channel->cl);
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return -EINTR;
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}
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msg = hsc_get_first_msg(channel, &channel->rx_msgs_queue);
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if (msg) {
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if (msg->status != HSI_STATUS_ERROR) {
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ret = copy_to_user((void __user *)buf,
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sg_virt(msg->sgt.sgl), hsc_msg_len_get(msg));
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if (ret)
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ret = -EFAULT;
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else
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ret = hsc_msg_len_get(msg);
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} else {
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ret = -EIO;
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}
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hsc_add_tail(channel, msg, &channel->free_msgs_list);
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}
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out:
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clear_bit(HSC_CH_READ, &channel->flags);
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return ret;
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}
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static ssize_t hsc_write(struct file *file, const char __user *buf, size_t len,
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loff_t *ppos __maybe_unused)
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{
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struct hsc_channel *channel = file->private_data;
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struct hsi_msg *msg;
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ssize_t ret;
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if ((len == 0) || !IS_ALIGNED(len, sizeof(u32)))
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return -EINVAL;
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if (len > max_data_size)
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len = max_data_size;
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if (channel->ch >= channel->cl->tx_cfg.num_hw_channels)
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return -ECHRNG;
|
|
if (test_and_set_bit(HSC_CH_WRITE, &channel->flags))
|
|
return -EBUSY;
|
|
msg = hsc_get_first_msg(channel, &channel->free_msgs_list);
|
|
if (!msg) {
|
|
clear_bit(HSC_CH_WRITE, &channel->flags);
|
|
return -ENOSPC;
|
|
}
|
|
if (copy_from_user(sg_virt(msg->sgt.sgl), (void __user *)buf, len)) {
|
|
ret = -EFAULT;
|
|
goto out;
|
|
}
|
|
hsc_msg_len_set(msg, len);
|
|
msg->complete = hsc_tx_completed;
|
|
msg->destructor = hsc_tx_msg_destructor;
|
|
ret = hsi_async_write(channel->cl, msg);
|
|
if (ret < 0)
|
|
goto out;
|
|
|
|
ret = wait_event_interruptible(channel->tx_wait,
|
|
!list_empty(&channel->tx_msgs_queue));
|
|
if (ret < 0) {
|
|
clear_bit(HSC_CH_WRITE, &channel->flags);
|
|
hsi_flush(channel->cl);
|
|
return -EINTR;
|
|
}
|
|
|
|
msg = hsc_get_first_msg(channel, &channel->tx_msgs_queue);
|
|
if (msg) {
|
|
if (msg->status == HSI_STATUS_ERROR)
|
|
ret = -EIO;
|
|
else
|
|
ret = hsc_msg_len_get(msg);
|
|
|
|
hsc_add_tail(channel, msg, &channel->free_msgs_list);
|
|
}
|
|
out:
|
|
clear_bit(HSC_CH_WRITE, &channel->flags);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static long hsc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
|
|
{
|
|
struct hsc_channel *channel = file->private_data;
|
|
unsigned int state;
|
|
struct hsc_rx_config rxc;
|
|
struct hsc_tx_config txc;
|
|
long ret = 0;
|
|
|
|
switch (cmd) {
|
|
case HSC_RESET:
|
|
hsi_flush(channel->cl);
|
|
break;
|
|
case HSC_SET_PM:
|
|
if (copy_from_user(&state, (void __user *)arg, sizeof(state)))
|
|
return -EFAULT;
|
|
if (state == HSC_PM_DISABLE) {
|
|
if (test_and_set_bit(HSC_CH_WLINE, &channel->flags))
|
|
return -EINVAL;
|
|
ret = hsi_start_tx(channel->cl);
|
|
} else if (state == HSC_PM_ENABLE) {
|
|
if (!test_and_clear_bit(HSC_CH_WLINE, &channel->flags))
|
|
return -EINVAL;
|
|
ret = hsi_stop_tx(channel->cl);
|
|
} else {
|
|
ret = -EINVAL;
|
|
}
|
|
break;
|
|
case HSC_SEND_BREAK:
|
|
return hsc_break_send(channel->cl);
|
|
case HSC_SET_RX:
|
|
if (copy_from_user(&rxc, (void __user *)arg, sizeof(rxc)))
|
|
return -EFAULT;
|
|
return hsc_rx_set(channel->cl, &rxc);
|
|
case HSC_GET_RX:
|
|
hsc_rx_get(channel->cl, &rxc);
|
|
if (copy_to_user((void __user *)arg, &rxc, sizeof(rxc)))
|
|
return -EFAULT;
|
|
break;
|
|
case HSC_SET_TX:
|
|
if (copy_from_user(&txc, (void __user *)arg, sizeof(txc)))
|
|
return -EFAULT;
|
|
return hsc_tx_set(channel->cl, &txc);
|
|
case HSC_GET_TX:
|
|
hsc_tx_get(channel->cl, &txc);
|
|
if (copy_to_user((void __user *)arg, &txc, sizeof(txc)))
|
|
return -EFAULT;
|
|
break;
|
|
default:
|
|
return -ENOIOCTLCMD;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static inline void __hsc_port_release(struct hsc_client_data *cl_data)
|
|
{
|
|
BUG_ON(cl_data->usecnt == 0);
|
|
|
|
if (--cl_data->usecnt == 0) {
|
|
hsi_flush(cl_data->cl);
|
|
hsi_release_port(cl_data->cl);
|
|
}
|
|
}
|
|
|
|
static int hsc_open(struct inode *inode, struct file *file)
|
|
{
|
|
struct hsc_client_data *cl_data;
|
|
struct hsc_channel *channel;
|
|
int ret = 0;
|
|
|
|
pr_debug("open, minor = %d\n", iminor(inode));
|
|
|
|
cl_data = container_of(inode->i_cdev, struct hsc_client_data, cdev);
|
|
mutex_lock(&cl_data->lock);
|
|
channel = cl_data->channels + (iminor(inode) & HSC_CH_MASK);
|
|
|
|
if (test_and_set_bit(HSC_CH_OPEN, &channel->flags)) {
|
|
ret = -EBUSY;
|
|
goto out;
|
|
}
|
|
/*
|
|
* Check if we have already claimed the port associated to the HSI
|
|
* client. If not then try to claim it, else increase its refcount
|
|
*/
|
|
if (cl_data->usecnt == 0) {
|
|
ret = hsi_claim_port(cl_data->cl, 0);
|
|
if (ret < 0)
|
|
goto out;
|
|
hsi_setup(cl_data->cl);
|
|
}
|
|
cl_data->usecnt++;
|
|
|
|
ret = hsc_msgs_alloc(channel);
|
|
if (ret < 0) {
|
|
__hsc_port_release(cl_data);
|
|
goto out;
|
|
}
|
|
|
|
file->private_data = channel;
|
|
mutex_unlock(&cl_data->lock);
|
|
|
|
return ret;
|
|
out:
|
|
mutex_unlock(&cl_data->lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int hsc_release(struct inode *inode __maybe_unused, struct file *file)
|
|
{
|
|
struct hsc_channel *channel = file->private_data;
|
|
struct hsc_client_data *cl_data = channel->cl_data;
|
|
|
|
mutex_lock(&cl_data->lock);
|
|
file->private_data = NULL;
|
|
if (test_and_clear_bit(HSC_CH_WLINE, &channel->flags))
|
|
hsi_stop_tx(channel->cl);
|
|
__hsc_port_release(cl_data);
|
|
hsc_reset_list(channel, &channel->rx_msgs_queue);
|
|
hsc_reset_list(channel, &channel->tx_msgs_queue);
|
|
hsc_reset_list(channel, &channel->free_msgs_list);
|
|
clear_bit(HSC_CH_READ, &channel->flags);
|
|
clear_bit(HSC_CH_WRITE, &channel->flags);
|
|
clear_bit(HSC_CH_OPEN, &channel->flags);
|
|
wake_up(&channel->rx_wait);
|
|
wake_up(&channel->tx_wait);
|
|
mutex_unlock(&cl_data->lock);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct file_operations hsc_fops = {
|
|
.owner = THIS_MODULE,
|
|
.read = hsc_read,
|
|
.write = hsc_write,
|
|
.unlocked_ioctl = hsc_ioctl,
|
|
.open = hsc_open,
|
|
.release = hsc_release,
|
|
};
|
|
|
|
static void hsc_channel_init(struct hsc_channel *channel)
|
|
{
|
|
init_waitqueue_head(&channel->rx_wait);
|
|
init_waitqueue_head(&channel->tx_wait);
|
|
spin_lock_init(&channel->lock);
|
|
INIT_LIST_HEAD(&channel->free_msgs_list);
|
|
INIT_LIST_HEAD(&channel->rx_msgs_queue);
|
|
INIT_LIST_HEAD(&channel->tx_msgs_queue);
|
|
}
|
|
|
|
static int hsc_probe(struct device *dev)
|
|
{
|
|
const char devname[] = "hsi_char";
|
|
struct hsc_client_data *cl_data;
|
|
struct hsc_channel *channel;
|
|
struct hsi_client *cl = to_hsi_client(dev);
|
|
unsigned int hsc_baseminor;
|
|
dev_t hsc_dev;
|
|
int ret;
|
|
int i;
|
|
|
|
cl_data = kzalloc(sizeof(*cl_data), GFP_KERNEL);
|
|
if (!cl_data)
|
|
return -ENOMEM;
|
|
|
|
hsc_baseminor = HSC_BASEMINOR(hsi_id(cl), hsi_port_id(cl));
|
|
if (!hsc_major) {
|
|
ret = alloc_chrdev_region(&hsc_dev, hsc_baseminor,
|
|
HSC_DEVS, devname);
|
|
if (ret == 0)
|
|
hsc_major = MAJOR(hsc_dev);
|
|
} else {
|
|
hsc_dev = MKDEV(hsc_major, hsc_baseminor);
|
|
ret = register_chrdev_region(hsc_dev, HSC_DEVS, devname);
|
|
}
|
|
if (ret < 0) {
|
|
dev_err(dev, "Device %s allocation failed %d\n",
|
|
hsc_major ? "minor" : "major", ret);
|
|
goto out1;
|
|
}
|
|
mutex_init(&cl_data->lock);
|
|
hsi_client_set_drvdata(cl, cl_data);
|
|
cdev_init(&cl_data->cdev, &hsc_fops);
|
|
cl_data->cdev.owner = THIS_MODULE;
|
|
cl_data->cl = cl;
|
|
for (i = 0, channel = cl_data->channels; i < HSC_DEVS; i++, channel++) {
|
|
hsc_channel_init(channel);
|
|
channel->ch = i;
|
|
channel->cl = cl;
|
|
channel->cl_data = cl_data;
|
|
}
|
|
|
|
/* 1 hsi client -> N char devices (one for each channel) */
|
|
ret = cdev_add(&cl_data->cdev, hsc_dev, HSC_DEVS);
|
|
if (ret) {
|
|
dev_err(dev, "Could not add char device %d\n", ret);
|
|
goto out2;
|
|
}
|
|
|
|
return 0;
|
|
out2:
|
|
unregister_chrdev_region(hsc_dev, HSC_DEVS);
|
|
out1:
|
|
kfree(cl_data);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int hsc_remove(struct device *dev)
|
|
{
|
|
struct hsi_client *cl = to_hsi_client(dev);
|
|
struct hsc_client_data *cl_data = hsi_client_drvdata(cl);
|
|
dev_t hsc_dev = cl_data->cdev.dev;
|
|
|
|
cdev_del(&cl_data->cdev);
|
|
unregister_chrdev_region(hsc_dev, HSC_DEVS);
|
|
hsi_client_set_drvdata(cl, NULL);
|
|
kfree(cl_data);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct hsi_client_driver hsc_driver = {
|
|
.driver = {
|
|
.name = "hsi_char",
|
|
.owner = THIS_MODULE,
|
|
.probe = hsc_probe,
|
|
.remove = hsc_remove,
|
|
},
|
|
};
|
|
|
|
static int __init hsc_init(void)
|
|
{
|
|
int ret;
|
|
|
|
if ((max_data_size < 4) || (max_data_size > 0x10000) ||
|
|
(max_data_size & (max_data_size - 1))) {
|
|
pr_err("Invalid max read/write data size\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
ret = hsi_register_client_driver(&hsc_driver);
|
|
if (ret) {
|
|
pr_err("Error while registering HSI/SSI driver %d\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
pr_info("HSI/SSI char device loaded\n");
|
|
|
|
return 0;
|
|
}
|
|
module_init(hsc_init);
|
|
|
|
static void __exit hsc_exit(void)
|
|
{
|
|
hsi_unregister_client_driver(&hsc_driver);
|
|
pr_info("HSI char device removed\n");
|
|
}
|
|
module_exit(hsc_exit);
|
|
|
|
MODULE_AUTHOR("Andras Domokos <andras.domokos@nokia.com>");
|
|
MODULE_ALIAS("hsi:hsi_char");
|
|
MODULE_DESCRIPTION("HSI character device");
|
|
MODULE_LICENSE("GPL v2");
|