diff options
Diffstat (limited to 'drivers/misc/mbox_channels-db5500.c')
| -rw-r--r-- | drivers/misc/mbox_channels-db5500.c | 1273 |
1 files changed, 1273 insertions, 0 deletions
diff --git a/drivers/misc/mbox_channels-db5500.c b/drivers/misc/mbox_channels-db5500.c new file mode 100644 index 00000000000..919be308ed4 --- /dev/null +++ b/drivers/misc/mbox_channels-db5500.c @@ -0,0 +1,1273 @@ +/* + * Copyright (C) ST-Ericsson SA 2010 + * + * Mailbox Logical Driver + * + * Author: Marcin Mielczarczyk <marcin.mielczarczyk@tieto.com> for ST-Ericsson. + * Bibek Basu ,bibek.basu@stericsson.com> + * License terms: GNU General Public License (GPL), version 2. + */ + +#include <asm/mach-types.h> +#include <linux/device.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/random.h> +#include <mach/mbox-db5500.h> +#include <mach/mbox_channels-db5500.h> +#include <linux/io.h> + +/* Defines start sequence number for given mailbox channel */ +#define CHANNEL_START_SEQUENCE_NUMBER 0x80 + +/* Defines number of channels per mailbox unit */ +#define CHANNELS_PER_MBOX_UNIT 256 + +/* + * This macro builds mbox channel PDU header with following format: + * --------------------------------------------------------------------------- + * | | | | | + * | Sequence nmbr | Type | Length | Destination logical channel number | + * | | | | | + * --------------------------------------------------------------------------- + * 31 24 20 16 0 + * + */ +#define BUILD_HEADER(chan, len, type, seq_no) \ + ((chan) | (((len) & 0xf) << 16) | \ + (((type) & 0xf) << 20) | ((seq_no) << 24)) + +/* Returns type from mbox message header */ +#define GET_TYPE(mbox_msg) (((mbox_msg) >> 20) & 0xf) + +/* Returns channel number from mbox message header */ +#define GET_CHANNEL(mbox_msg) ((mbox_msg) & 0xffff) + +/* Returns length of payload from mbox message header */ +#define GET_LENGTH(mbox_msg) (((mbox_msg) >> 16) & 0xf) + +/* Returns sequence number from mbox message header */ +#define GET_SEQ_NUMBER(mbox_msg) (((mbox_msg) >> 24) + +enum mbox_msg{ + MBOX_CLOSE, + MBOX_OPEN, + MBOX_SEND, + MBOX_CAST, + MBOX_ACK, + MBOX_NAK, +}; + +enum mbox_dir { + MBOX_TX, + MBOX_RX, +}; + +struct mbox_channel_mapping { + u16 chan_base; + u8 mbox_id; + enum mbox_dir direction; +}; + +/* This table maps mbox logical channel to mbox id and direction */ +static struct mbox_channel_mapping channel_mappings[] = { + {0x500, 2, MBOX_RX}, /* channel 5 maps to mbox 0.1, dsp->app (unsec) */ + {0x900, 2, MBOX_TX}, /* channel 9 maps to mbox 0.0, app->dsp (unsec) */ +}; + +/* This table specifies mailbox ids which mbox channels module will use */ +static u8 mbox_ids[] = { + 2, /* app <-> dsp (unsec) */ +}; + +/** + * struct mbox_unit_status - current status of mbox unit + * @mbox_id : holds mbox unit identification number + * @mbox : holds mbox pointer after mbox_register() call + * @tx_chans : holds list of open tx mbox channels + * @tx_lock: lock for tx channel + * @rx_chans : holds list of open rx mbox channels + * @rx_lock: lock for rx channel + */ +struct mbox_unit_status { + u8 mbox_id; + struct mbox *mbox; + struct list_head tx_chans; + spinlock_t tx_lock; + struct list_head rx_chans; + spinlock_t rx_lock; +}; + +static struct { + struct platform_device *pdev; + struct mbox_unit_status mbox_unit[ARRAY_SIZE(mbox_ids)]; +} channels; + +/* This structure describes pending element for mbox tx channel */ +struct pending_elem { + struct list_head list; + u32 *data; + u8 length; +}; + +struct rx_pending_elem { + u32 buffer[MAILBOX_NR_OF_DATAWORDS]; + u8 length; + void *priv; +}; + +struct rx_pending_elem rx_pending[NUM_DSP_BUFFER]; + +/* This structure holds list of pending elements for mbox tx channel */ +struct tx_channel { + struct list_head pending; +}; + +/* Specific status for mbox rx channel */ +struct rx_channel { + struct list_head pending; + spinlock_t lock; + u32 buffer[MAILBOX_NR_OF_DATAWORDS]; + u8 index; + u8 length; +}; + +/** + * struct channel_status - status of mbox channel - common for tx and rx + * @list : holds list of channels registered + * @channel : holds channel number + * @state : holds state of channel + * @cb: holds callback function forr rx channel + * @with_ack : holds if ack is needed + * @rx: holds pointer to rx_channel + * @tx : holds pointer to tx_channel + * @receive_wq : holds pointer to receive workqueue_struct + * @cast_wq : holds pointer to cast workqueue_struct + * @open_msg: holds work_struct for open msg + * @receive_msg : holds work_struct for receive msg + * @cast_msg: holds work_struct for cast msg + * @lock: holds lock for channel + */ +struct channel_status { + atomic_t rcv_counter; + struct list_head list; + u16 channel; + int state; + mbox_channel_cb_t *cb; + void *priv; + u8 seq_number; + bool with_ack; + struct rx_channel rx; + struct tx_channel tx; + struct workqueue_struct *receive_wq; + struct workqueue_struct *cast_wq; + struct work_struct open_msg; + struct work_struct receive_msg; + struct work_struct cast_msg; + struct mutex lock; +}; + +/* Checks if provided channel number is valid */ +static bool check_channel(u16 channel, enum mbox_dir direction) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(channel_mappings); i++) { + if ((channel >= channel_mappings[i].chan_base) && + (channel < channel_mappings[i].chan_base + + CHANNELS_PER_MBOX_UNIT)) { + /* Check if direction of given channel is correct*/ + if (channel_mappings[i].direction == direction) + return true; + else + break; + } + } + return false; +} + +/* get the tx channel corresponding to the given rx channel */ +static u16 get_tx_channel(u16 channel) +{ + int i; + int relative_chan = 0; + int mbox_id = 0xFF; + u16 tx_channel = 0xFF; + + for (i = 0; i < ARRAY_SIZE(channel_mappings); i++) { + if ((channel >= channel_mappings[i].chan_base) && + (channel < channel_mappings[i].chan_base + + CHANNELS_PER_MBOX_UNIT)) { + /* Check if direction of given channel is correct*/ + relative_chan = channel - channel_mappings[i].chan_base; + mbox_id = channel_mappings[i].mbox_id; + + } + } + + for (i = 0; i < ARRAY_SIZE(channel_mappings); i++) { + if ((mbox_id == channel_mappings[i].mbox_id) && + (channel_mappings[i].direction == MBOX_TX)) + tx_channel = channel_mappings[i].chan_base + + relative_chan; + } + return tx_channel; +} + +/* Returns mbox unit id for given mbox channel */ +static int get_mbox_id(u16 channel) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(channel_mappings); i++) { + if ((channel >= channel_mappings[i].chan_base) && + (channel < channel_mappings[i].chan_base + + CHANNELS_PER_MBOX_UNIT)) { + return channel_mappings[i].mbox_id; + } + } + /* There is no mbox unit registered for given channel */ + return -EINVAL; +} + +/* Returns mbox structure saved after mbox_register() call */ +static struct mbox *get_mbox(u16 channel) +{ + int i; + int mbox_id = get_mbox_id(channel); + + if (mbox_id < 0) { + dev_err(&channels.pdev->dev, "couldn't get mbox id\n"); + return NULL; + } + + for (i = 0; i < ARRAY_SIZE(channels.mbox_unit); i++) { + if (channels.mbox_unit[i].mbox_id == mbox_id) + return channels.mbox_unit[i].mbox; + } + return NULL; +} + +/* Returns pointer to rx mbox channels list for given mbox unit */ +static struct list_head *get_rx_list(u8 mbox_id) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(mbox_ids); i++) { + if (channels.mbox_unit[i].mbox_id == mbox_id) + return &channels.mbox_unit[i].rx_chans; + } + return NULL; +} + +/* Returns pointer to tx mbox channels list for given mbox unit */ +static struct list_head *get_tx_list(u8 mbox_id) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(mbox_ids); i++) { + if (channels.mbox_unit[i].mbox_id == mbox_id) + return &channels.mbox_unit[i].tx_chans; + } + return NULL; +} + +static int send_pdu(struct channel_status *chan_status, int command, + u16 channel) +{ + struct mbox *mbox; + u32 header = 0; + int ret = 0; + /* SEND PDU is not supported */ + if (command == MBOX_SEND) { + dev_err(&channels.pdev->dev, "SEND command not implemented\n"); + ret = -EINVAL; + goto exit; + } + mbox = get_mbox(chan_status->channel); + if (mbox == NULL) { + dev_err(&channels.pdev->dev, "couldn't get mailbox\n"); + ret = -ENOSYS; + goto exit; + } + /* For CAST type send all pending messages */ + if (command == MBOX_CAST) { + struct list_head *pos, *n; + + /* Send all pending messages from TX channel */ + list_for_each_safe(pos, n, &chan_status->tx.pending) { + struct pending_elem *pending = + list_entry(pos, struct pending_elem, list); + int i; + + header = BUILD_HEADER(channel, + pending->length, + command, + chan_status->seq_number); + + ret = mbox_send(mbox, header, true); + if (ret < 0) { + dev_err(&channels.pdev->dev, + "failed to send header, err=%d\n", ret); + goto exit; + } + + for (i = 0; i < pending->length; i++) { + ret = mbox_send(mbox, pending->data[i], true); + if (ret < 0) { + dev_err(&channels.pdev->dev, + "failed to send header, err=%d\n", ret); + goto exit; + } + } + + /* Call client's callback that data is already sent */ + if (chan_status->cb) + chan_status->cb(pending->data, pending->length, + chan_status->priv); + else + dev_err(&channels.pdev->dev, + "%s no callback provided:header 0x%x\n", + __func__, header); + + /* Increment sequence number */ + chan_status->seq_number++; + + /* Remove and free element from the list */ + list_del(&pending->list); + kfree(pending); + } + } else { + header = BUILD_HEADER(channel, 0, + command, chan_status->seq_number); + + ret = mbox_send(mbox, header, true); + if (ret < 0) + dev_err(&channels.pdev->dev, "failed to send header\n"); + /* Increment sequence number */ + chan_status->seq_number++; + } + +exit: + return ret; +} + +void mbox_handle_receive_msg(struct work_struct *work) +{ + struct channel_status *rx_chan = container_of(work, + struct channel_status, + receive_msg); + + if (!atomic_read(&rx_chan->rcv_counter)) + return; +rcv_msg: + /* Call client's callback and reset state */ + if (rx_chan->cb) { + static int rx_pending_count; + rx_chan->cb(rx_pending[rx_pending_count].buffer, + rx_pending[rx_pending_count].length, + rx_pending[rx_pending_count].priv); + rx_pending_count++; + if (rx_pending_count == NUM_DSP_BUFFER) + rx_pending_count = 0; + } else { + dev_err(&channels.pdev->dev, + "%s no callback provided\n", __func__); + } + if (atomic_dec_return(&rx_chan->rcv_counter) > 0) + goto rcv_msg; + +} + +void mbox_handle_open_msg(struct work_struct *work) +{ + struct channel_status *tx_chan = container_of(work, + struct channel_status, + open_msg); + /* Change channel state to OPEN */ + tx_chan->state = MBOX_OPEN; + /* If pending list not empty, start sending data */ + mutex_lock(&tx_chan->lock); + if (!list_empty(&tx_chan->tx.pending)) + send_pdu(tx_chan, MBOX_CAST, tx_chan->channel); + mutex_unlock(&tx_chan->lock); +} + +void mbox_handle_cast_msg(struct work_struct *work) +{ + struct channel_status *rx_chan = container_of(work, + struct channel_status, + cast_msg); + /* Check if channel is opened */ + if (rx_chan->state == MBOX_CLOSE) { + /* Peer sent message to closed channel */ + dev_err(&channels.pdev->dev, + "channel in wrong state\n"); + } +} + +static bool handle_receive_msg(u32 mbox_msg, struct channel_status *rx_chan) +{ + int i; + static int rx_pending_count; + + if (rx_chan) { + /* Store received data in RX channel buffer */ + rx_chan->rx.buffer[rx_chan->rx.index++] = mbox_msg; + + /* Check if it's last data of PDU */ + if (rx_chan->rx.index == rx_chan->rx.length) { + for (i = 0; i < MAILBOX_NR_OF_DATAWORDS; i++) { + rx_pending[rx_pending_count].buffer[i] = + rx_chan->rx.buffer[i]; + } + + rx_pending[rx_pending_count].length = + rx_chan->rx.length; + rx_pending[rx_pending_count].priv = rx_chan->priv; + rx_chan->rx.index = 0; + rx_chan->rx.length = 0; + rx_chan->state = MBOX_OPEN; + rx_chan->seq_number++; + rx_pending_count++; + if (rx_pending_count == NUM_DSP_BUFFER) + rx_pending_count = 0; + atomic_inc(&rx_chan->rcv_counter); + queue_work(rx_chan->receive_wq, + &rx_chan->receive_msg); + } + dev_dbg(&channels.pdev->dev, "%s OK\n", __func__); + + return true; + } + return false; +} + +static void handle_open_msg(u16 channel, u8 mbox_id) +{ + struct list_head *tx_list, *pos; + struct channel_status *tmp; + struct channel_status *tx_chan = NULL; + struct mbox_unit_status *mbox_unit; + channel = get_tx_channel(channel); + dev_dbg(&channels.pdev->dev, "%s mbox_id %d\tchannel %x\n", + __func__, mbox_id, channel); + /* Get TX channel for given mbox unit */ + tx_list = get_tx_list(mbox_id); + if (tx_list == NULL) { + dev_err(&channels.pdev->dev, "given mbox id is not valid %d\n", + mbox_id); + return; + } + mbox_unit = container_of(tx_list, struct mbox_unit_status, tx_chans); + /* Search for channel in tx list */ + spin_lock(&mbox_unit->tx_lock); + list_for_each(pos, tx_list) { + tmp = list_entry(pos, struct channel_status, list); + dev_dbg(&channels.pdev->dev, "tmp->channel=%d\n", + tmp->channel); + if (tmp->channel == channel) + tx_chan = tmp; + } + spin_unlock(&mbox_unit->tx_lock); + if (tx_chan) { + schedule_work(&tx_chan->open_msg); + } else { + /* No tx channel found on the list, allocate new element */ + tx_chan = kzalloc(sizeof(*tx_chan), GFP_ATOMIC); + if (tx_chan == NULL) { + dev_err(&channels.pdev->dev, + "failed to allocate memory\n"); + return; + } + + /* Fill initial data and add this element to tx list */ + tx_chan->channel = get_tx_channel(channel); + tx_chan->state = MBOX_OPEN; + tx_chan->seq_number = CHANNEL_START_SEQUENCE_NUMBER; + INIT_LIST_HEAD(&tx_chan->tx.pending); + INIT_WORK(&tx_chan->open_msg, mbox_handle_open_msg); + INIT_WORK(&tx_chan->cast_msg, mbox_handle_cast_msg); + INIT_WORK(&tx_chan->receive_msg, mbox_handle_receive_msg); + mutex_init(&tx_chan->lock); + spin_lock(&mbox_unit->tx_lock); + list_add_tail(&tx_chan->list, tx_list); + spin_unlock(&mbox_unit->tx_lock); + } +} + +static void handle_cast_msg(u16 channel, struct channel_status *rx_chan, + u32 mbox_msg, bool send) +{ + dev_dbg(&channels.pdev->dev, " %s\n", __func__); + if (rx_chan) { + rx_chan->rx.buffer[0] = mbox_msg; + rx_chan->with_ack = send; + rx_chan->rx.length = GET_LENGTH(rx_chan->rx.buffer[0]); + if (rx_chan->rx.length <= MAILBOX_NR_OF_DATAWORDS && + rx_chan->rx.length > 0) { + rx_chan->rx.index = 0; + rx_chan->state = MBOX_CAST; + } + queue_work(rx_chan->cast_wq, + &rx_chan->cast_msg); + } else { + /* Channel not found, peer sent wrong message */ + dev_err(&channels.pdev->dev, "channel %d doesn't exist\n", + channel); + } +} + +/* + * This callback is called whenever mbox unit receives data. + * priv parameter holds mbox unit id. + */ +static void mbox_cb(u32 mbox_msg, void *priv) +{ + u8 mbox_id = *(u8 *)priv; + struct list_head *rx_list; + u8 type = GET_TYPE(mbox_msg); + u16 channel = GET_CHANNEL(mbox_msg); + struct mbox_unit_status *mbox_unit; + struct list_head *pos; + struct channel_status *tmp; + struct channel_status *rx_chan = NULL; + bool is_Payload = 0; + + dev_dbg(&channels.pdev->dev, "%s type %d\t, mbox_msg %x\n", + __func__, type, mbox_msg); + + /* Get RX channels list for given mbox unit */ + rx_list = get_rx_list(mbox_id); + if (rx_list == NULL) { + dev_err(&channels.pdev->dev, "given mbox id is not valid %d\n", + mbox_id); + return; + } + + mbox_unit = container_of(rx_list, struct mbox_unit_status, rx_chans); + /* Search for channel in rx list */ + spin_lock(&mbox_unit->rx_lock); + list_for_each(pos, rx_list) { + tmp = list_entry(pos, struct channel_status, list); + if (tmp->state == MBOX_SEND || + tmp->state == MBOX_CAST) { + /* Received message is payload */ + is_Payload = 1; + rx_chan = tmp; + } else + if (tmp->channel == channel) + rx_chan = tmp; + } + spin_unlock(&mbox_unit->rx_lock); + /* if callback is present for that RX channel */ + if (rx_chan && rx_chan->cb) { + /* If received message is payload this + * function will take care of it + */ + if ((is_Payload) && (handle_receive_msg(mbox_msg, rx_chan))) + return; + } else + dev_err(&channels.pdev->dev, "callback not present:msg 0x%x " + "rx_chan 0x%x\n", mbox_msg, (u32)rx_chan); + + /* Received message is header as no RX channel is in SEND/CAST state */ + switch (type) { + case MBOX_CLOSE: + /* Not implemented */ + break; + case MBOX_OPEN: + handle_open_msg(channel, mbox_id); + break; + case MBOX_SEND: + /* if callback is present for that RX channel */ + if (rx_chan && rx_chan->cb) + handle_cast_msg(channel, rx_chan, mbox_msg, true); + break; + case MBOX_CAST: + /* if callback is present for that RX channel */ + if (rx_chan && rx_chan->cb) + handle_cast_msg(channel, rx_chan, mbox_msg, false); + break; + case MBOX_ACK: + case MBOX_NAK: + /* Not implemented */ + break; + } +} + +/** + * mbox_channel_register() - Registers for a channel + * @channel: Channel Number. + * @cb: Pointer to function pointer mbox_channel_cb_t + * @priv: Pointer to private data + * + * This routine is used to register for a logical channel. + * It first does sanity check on the requested channel availability + * and parameters. Then it prepares internal entry for the channel. + * And send a OPEN request for that channel. + */ +int mbox_channel_register(u16 channel, mbox_channel_cb_t *cb, void *priv) +{ + struct channel_status *rx_chan; + struct list_head *pos, *rx_list; + int res = 0; + struct mbox_unit_status *mbox_unit; + + dev_dbg(&channels.pdev->dev, " %s channel = %d\n", __func__, channel); + /* Check for callback fcn */ + if (cb == NULL) { + dev_err(&channels.pdev->dev, + "channel callback missing:channel %d\n", channel); + res = -EINVAL; + goto exit; + } + + /* Check if provided channel number is valid */ + if (!check_channel(channel, MBOX_RX)) { + dev_err(&channels.pdev->dev, "wrong mbox channel number %d\n", + channel); + res = -EINVAL; + goto exit; + } + + rx_list = get_rx_list(get_mbox_id(channel)); + if (rx_list == NULL) { + dev_err(&channels.pdev->dev, "given mbox id is not valid\n"); + res = -EINVAL; + goto exit; + } + + mbox_unit = container_of(rx_list, struct mbox_unit_status, rx_chans); + + /* Check if channel is already registered */ + spin_lock(&mbox_unit->rx_lock); + list_for_each(pos, rx_list) { + rx_chan = list_entry(pos, struct channel_status, list); + + if (rx_chan->channel == channel) { + dev_dbg(&channels.pdev->dev, + "channel already registered\n"); + rx_chan->cb = cb; + rx_chan->priv = priv; + spin_unlock(&mbox_unit->rx_lock); + goto exit; + } + } + spin_unlock(&mbox_unit->rx_lock); + + rx_chan = kzalloc(sizeof(*rx_chan), GFP_KERNEL); + if (rx_chan == NULL) { + dev_err(&channels.pdev->dev, + "couldn't allocate channel status\n"); + res = -ENOMEM; + goto exit; + } + + atomic_set(&rx_chan->rcv_counter, 0); + /* Fill out newly allocated element and add it to rx list */ + rx_chan->channel = channel; + rx_chan->cb = cb; + rx_chan->priv = priv; + rx_chan->seq_number = CHANNEL_START_SEQUENCE_NUMBER; + mutex_init(&rx_chan->lock); + INIT_LIST_HEAD(&rx_chan->rx.pending); + rx_chan->cast_wq = create_singlethread_workqueue("mbox_cast_msg"); + if (!rx_chan->cast_wq) { + dev_err(&channels.pdev->dev, "failed to create work queue\n"); + res = -ENOMEM; + goto error_cast_wq; + } + rx_chan->receive_wq = create_singlethread_workqueue("mbox_receive_msg"); + if (!rx_chan->receive_wq) { + dev_err(&channels.pdev->dev, "failed to create work queue\n"); + res = -ENOMEM; + goto error_recv_wq; + } + INIT_WORK(&rx_chan->open_msg, mbox_handle_open_msg); + INIT_WORK(&rx_chan->cast_msg, mbox_handle_cast_msg); + INIT_WORK(&rx_chan->receive_msg, mbox_handle_receive_msg); + spin_lock(&mbox_unit->rx_lock); + list_add_tail(&rx_chan->list, rx_list); + spin_unlock(&mbox_unit->rx_lock); + + mutex_lock(&rx_chan->lock); + res = send_pdu(rx_chan, MBOX_OPEN, get_tx_channel(rx_chan->channel)); + if (res) { + dev_err(&channels.pdev->dev, "failed to send OPEN command\n"); + spin_lock(&mbox_unit->rx_lock); + list_del(&rx_chan->list); + spin_unlock(&mbox_unit->rx_lock); + mutex_unlock(&rx_chan->lock); + goto error_send_pdu; + } else { + rx_chan->seq_number++; + rx_chan->state = MBOX_OPEN; + mutex_unlock(&rx_chan->lock); + return res; + } +error_send_pdu: + flush_workqueue(rx_chan->receive_wq); +error_recv_wq: + flush_workqueue(rx_chan->cast_wq); +error_cast_wq: + kfree(rx_chan); +exit: + return res; +} +EXPORT_SYMBOL(mbox_channel_register); + +/** + * mbox_channel_deregister() - DeRegisters for a channel + * @channel: Channel Number. + * + * This routine is used to deregister for a logical channel. + * It first does sanity check on the requested channel availability + * and parameters. Then it deletes the channel + */ +int mbox_channel_deregister(u16 channel) +{ + struct channel_status *rx_chan = NULL; + struct list_head *pos, *rx_list; + int res = 0; + struct mbox_unit_status *mbox_unit; + + dev_dbg(&channels.pdev->dev, " %s channel = %d\n", __func__, channel); + /* Check if provided channel number is valid */ + if (!check_channel(channel, MBOX_RX)) { + dev_err(&channels.pdev->dev, "wrong mbox channel number %d\n", + channel); + res = -EINVAL; + goto exit; + } + + rx_list = get_rx_list(get_mbox_id(channel)); + if (rx_list == NULL) { + dev_err(&channels.pdev->dev, "given mbox id is not valid\n"); + res = -EINVAL; + goto exit; + } + + mbox_unit = container_of(rx_list, struct mbox_unit_status, rx_chans); + + /* Check if channel is already registered */ + spin_lock(&mbox_unit->rx_lock); + list_for_each(pos, rx_list) { + rx_chan = list_entry(pos, struct channel_status, list); + + if (rx_chan->channel == channel) { + dev_dbg(&channels.pdev->dev, + "channel found\n"); + rx_chan->cb = NULL; + } + } + list_del(&rx_chan->list); + spin_unlock(&mbox_unit->rx_lock); + flush_workqueue(rx_chan->cast_wq); + flush_workqueue(rx_chan->receive_wq); + kfree(rx_chan); + +exit: + return res; +} +EXPORT_SYMBOL(mbox_channel_deregister); + +/** + * mbox_channel_send() - Send messages + * @msg: Pointer to mbox_channel_msg data structure. + * + * This routine is used to send messages over the registered logical + * TX channel. It first does sanity check on the message paramenters. + * It registered channel is not found then it just registers for that + * channel. If channel found, it puts the message to the pending list. + * If channel is OPEN, it then pushes the message to the mailbox in + * FIFO manner from the pending list. + */ +int mbox_channel_send(struct mbox_channel_msg *msg) +{ + struct list_head *pos, *tx_list; + struct channel_status *tmp = NULL; + struct channel_status *tx_chan = NULL; + struct pending_elem *pending; + struct mbox_unit_status *mbox_unit; + int res = 0; + + if (msg->length > MAILBOX_NR_OF_DATAWORDS || msg->length == 0) { + dev_err(&channels.pdev->dev, "data length incorrect\n"); + res = -EINVAL; + goto exit; + } + + if (!check_channel(msg->channel, MBOX_TX)) { + dev_err(&channels.pdev->dev, "wrong channel number %d\n", + msg->channel); + res = -EINVAL; + goto exit; + } + + tx_list = get_tx_list(get_mbox_id(msg->channel)); + if (tx_list == NULL) { + dev_err(&channels.pdev->dev, "given mbox id is not valid\n"); + res = -EINVAL; + goto exit; + } + + mbox_unit = container_of(tx_list, struct mbox_unit_status, tx_chans); + + spin_lock(&mbox_unit->tx_lock); + dev_dbg(&channels.pdev->dev, "send:tx_list=%x\tmbox_unit=%x\n", + (u32)tx_list, (u32)mbox_unit); + list_for_each(pos, tx_list) { + tmp = list_entry(pos, struct channel_status, list); + if (tmp->channel == msg->channel) + tx_chan = tmp; + } + spin_unlock(&mbox_unit->tx_lock); + /* Allocate pending element and add it to the list */ + pending = kzalloc(sizeof(*pending), GFP_KERNEL); + if (pending == NULL) { + dev_err(&channels.pdev->dev, + "couldn't allocate memory for pending\n"); + res = -ENOMEM; + goto exit; + } + pending->data = msg->data; + pending->length = msg->length; + + if (tx_chan) { + mutex_lock(&tx_chan->lock); + list_add_tail(&pending->list, &tx_chan->tx.pending); + tx_chan->cb = msg->cb; + tx_chan->priv = msg->priv; + /* If channel is already opened start sending data */ + if (tx_chan->state == MBOX_OPEN) + send_pdu(tx_chan, MBOX_CAST, tx_chan->channel); + /* Stop processing here */ + mutex_unlock(&tx_chan->lock); + } else { + /* No channel found on the list, allocate new element */ + tx_chan = kzalloc(sizeof(*tx_chan), GFP_KERNEL); + if (tx_chan == NULL) { + dev_err(&channels.pdev->dev, + "couldn't allocate memory for \ + tx_chan\n"); + res = -ENOMEM; + goto exit; + } + tx_chan->channel = msg->channel; + tx_chan->cb = msg->cb; + tx_chan->priv = msg->priv; + tx_chan->state = MBOX_CLOSE; + tx_chan->seq_number = CHANNEL_START_SEQUENCE_NUMBER; + INIT_LIST_HEAD(&tx_chan->tx.pending); + INIT_WORK(&tx_chan->open_msg, mbox_handle_open_msg); + INIT_WORK(&tx_chan->cast_msg, mbox_handle_cast_msg); + INIT_WORK(&tx_chan->receive_msg, mbox_handle_receive_msg); + mutex_init(&tx_chan->lock); + spin_lock(&mbox_unit->tx_lock); + list_add_tail(&tx_chan->list, tx_list); + spin_unlock(&mbox_unit->tx_lock); + mutex_lock(&tx_chan->lock); + list_add_tail(&pending->list, &tx_chan->tx.pending); + mutex_unlock(&tx_chan->lock); + } + return 0; + +exit: + return res; +} +EXPORT_SYMBOL(mbox_channel_send); + +static void revoke_pending_msgs(struct channel_status *tx_chan) +{ + struct list_head *pos, *n; + struct pending_elem *pending; + + list_for_each_safe(pos, n, &tx_chan->tx.pending) { + pending = list_entry(pos, struct pending_elem, list); + + if (tx_chan->cb) + tx_chan->cb(pending->data, pending->length, + tx_chan->priv); + else + dev_err(&channels.pdev->dev, + "%s no callback provided\n", __func__); + list_del(&pending->list); + kfree(pending); + } +} + +/** + * mbox_channel_revoke_messages() - Revoke pending messages + * @channel: Channel on which action to be taken. + * + * This routine Clear all pending messages from TX channel + * It searches for the channel.Checks if there is pending + * messages.Calls if tehre is any registered function. And + * deletes the messages for the pending list. + */ +int mbox_channel_revoke_messages(u16 channel) +{ + struct list_head *pos, *tx_list; + struct channel_status *tmp; + struct channel_status *tx_chan = NULL; + struct mbox_unit_status *mbox_unit; + int res = 0; + + if (!check_channel(channel, MBOX_TX)) { + dev_err(&channels.pdev->dev, + "wrong channel number %d\n", channel); + return -EINVAL; + } + + tx_list = get_tx_list(get_mbox_id(channel)); + if (tx_list == NULL) { + dev_err(&channels.pdev->dev, "given mbox id is not valid\n"); + return -EINVAL; + } + + mbox_unit = container_of(tx_list, struct mbox_unit_status, tx_chans); + + spin_lock(&mbox_unit->tx_lock); + list_for_each(pos, tx_list) { + tmp = list_entry(pos, struct channel_status, list); + if (tmp->channel == channel) + tx_chan = tmp; + } + spin_unlock(&mbox_unit->tx_lock); + + if (tx_chan) { + mutex_lock(&tx_chan->lock); + revoke_pending_msgs(tx_chan); + mutex_unlock(&tx_chan->lock); + dev_dbg(&channels.pdev->dev, "channel %d cleared\n", + channel); + } else { + dev_err(&channels.pdev->dev, "no channel found\n"); + res = -EINVAL; + } + + dev_dbg(&channels.pdev->dev, "%s exiting %d\n", __func__, res); + return res; +} +EXPORT_SYMBOL(mbox_channel_revoke_messages); + +#if defined(CONFIG_DEBUG_FS) +#define MBOXTEST_DEBUG 1 +#ifdef MBOXTEST_DEBUG +#define DBG_TEST(x) x +#else +#define DBG_TEST(x) +#endif + +#define MBOX_TEST_MAX_WORDS 3 +#define MBOX_RX_CHAN 0x500 +#define MBOX_TX_RX_CHANNEL_DIFF 0x400 +#define MBOX_MAX_NUM_TRANSFER 30000 +static int registration_done; +/** + * struct mboxtest_data - mbox test via debugfs information + * @rx_buff: Buffer for incomming data + * @rx_pointer: Ptr to actual RX data buff + * @tx_buff: Buffer for outgoing data + * @tx_pointer: Ptr to actual TX data buff + * @tx_done: TX Transfer done indicator + * @rx_done: RX Transfer done indicator + * @received: Received words + * @xfer_words: Num of bytes in actual trf + * @xfers: Number of transfers + * @words: Number of total words + * @channel: Channel test number + */ +struct mboxtest_data { + unsigned int *rx_buff; + unsigned int *rx_pointer; + unsigned int *tx_buff; + unsigned int *tx_pointer; + struct completion tx_done; + struct completion rx_done; + int received; + int xfer_words; + int xfers; + int words; + int channel; +}; + +static void mboxtest_receive_cb(u32 *data, u32 len, void *arg) +{ + struct mboxtest_data *mboxtest = (struct mboxtest_data *) arg; + int i; + + printk(KERN_INFO "receive_cb.. data.= 0x%X, len = %d\n", + *data, len); + for (i = 0; i < len; i++) + *(mboxtest->rx_pointer++) = *(data++); + + mboxtest->received += len; + + printk(KERN_INFO "received = %d, words = %d\n", + mboxtest->received, mboxtest->words); + if (mboxtest->received >= mboxtest->words) + complete(&mboxtest->rx_done); + dev_dbg(&channels.pdev->dev, "%s exiting\n", __func__); +} + +static void mboxtest_send_cb(u32 *data, u32 len, void *arg) +{ + struct mboxtest_data *mboxtest = (struct mboxtest_data *) arg; + + printk(KERN_INFO "send_cb.. data.= 0x%X, len = %d\n", + *data, len); + + complete(&mboxtest->tx_done); + dev_dbg(&channels.pdev->dev, "kernel:mboxtest_send_cb exiting\n"); +} + +static int mboxtest_transmit(struct mboxtest_data *mboxtest) +{ + int status = 0; + struct mbox_channel_msg msg; + + dev_dbg(&channels.pdev->dev, "%s entering\n", __func__); + init_completion(&mboxtest->tx_done); + + msg.channel = mboxtest->channel; + msg.data = mboxtest->tx_pointer; + msg.length = mboxtest->words; + msg.cb = mboxtest_send_cb; + msg.priv = mboxtest; + + status = mbox_channel_send(&msg); + if (!status) { + mboxtest->tx_pointer += mboxtest->xfer_words; + wait_for_completion(&mboxtest->tx_done); + } + + dev_dbg(&channels.pdev->dev, "%s exiting %d\n", + __func__, status); + return status; +} + +static int transfer_test(struct mboxtest_data *mboxtest) +{ + int status = 0; + int len = 0; + int i; + + len = mboxtest->words; + + dev_dbg(&channels.pdev->dev, "%s enterring\n", __func__); + /* Allocate buffers */ + mboxtest->rx_buff = kzalloc(sizeof(unsigned int) * len, GFP_KERNEL); + if (!mboxtest->rx_buff) { + DBG_TEST(printk(KERN_INFO + "Cannot allocate mbox rx memory\n")); + status = -ENOMEM; + goto err1; + } + memset(mboxtest->rx_buff, '\0', sizeof(unsigned int) * len); + + mboxtest->tx_buff = kzalloc(sizeof(unsigned int) * len, GFP_KERNEL); + if (!mboxtest->tx_buff) { + DBG_TEST(printk(KERN_INFO + "Cannot allocate mbox tx memory\n")); + status = -ENOMEM; + goto err2; + } + memset(mboxtest->tx_buff, '\0', sizeof(unsigned int) * len); + + /* Generate data */ + get_random_bytes((unsigned char *)mboxtest->tx_buff, + sizeof(unsigned int) * len); + /* Set pointers */ + mboxtest->tx_pointer = mboxtest->tx_buff; + mboxtest->rx_pointer = mboxtest->rx_buff; + mboxtest->received = 0; + init_completion(&mboxtest->rx_done); + + /* Start tx transfer test transfer */ + status = mboxtest_transmit(mboxtest); + DBG_TEST(printk(KERN_INFO "xfer_words=%d\n", + mboxtest->xfer_words)); + if (!status) + wait_for_completion(&mboxtest->rx_done); + for (i = 0; i < len; i++) + DBG_TEST(printk(KERN_INFO "%d -> TX:0x%X, RX:0x%X\n", i, + mboxtest->tx_buff[i], mboxtest->rx_buff[i])); + + dev_dbg(&channels.pdev->dev, "%s exiting %d\n", __func__, status); + return status; +err2: + kfree(mboxtest->rx_buff); +err1: + return status; +} + +static int mboxtest_prepare(struct mboxtest_data *mboxtest) +{ + int err = 0; + + mboxtest->xfers = MBOX_MAX_NUM_TRANSFER; + /* Calculate number of bytes in each transfer */ + mboxtest->xfer_words = mboxtest->words / mboxtest->xfers; + + /* Trim to maxiumum data words per transfer */ + if (mboxtest->xfer_words > MBOX_TEST_MAX_WORDS) { + DBG_TEST(printk(KERN_INFO "Recalculating xfers ...\n")); + mboxtest->xfer_words = MBOX_TEST_MAX_WORDS; + if (mboxtest->words % mboxtest->xfer_words) + mboxtest->xfers = (mboxtest->words / + mboxtest->xfer_words) + 1; + else + mboxtest->xfers = (mboxtest->words / + mboxtest->xfer_words); + } + + DBG_TEST(printk(KERN_INFO "Params: chan=0x%X words=%d, xfers=%d\n", + mboxtest->channel, mboxtest->words, + mboxtest->xfers)); + + if (mbox_channel_register(mboxtest->channel, + mboxtest_receive_cb, mboxtest)) { + DBG_TEST(printk(KERN_INFO "Cannot register mbox channel\n")); + err = -ENOMEM; + goto err; + } + + registration_done = true; + return 0; +err: + return err; +} + +struct mboxtest_data mboxtest; +/* + * Expected input: <nbr_channel> <nbr_word> + * Example: "echo 500 2" + */ +static ssize_t mbox_write_channel(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t count) +{ + unsigned long nbr_channel; + unsigned long nbr_word; + char int_buf[16]; + char *token; + char *val; + + strncpy((char *) &int_buf, buf, sizeof(int_buf)); + token = (char *) &int_buf; + + /* Parse message */ + val = strsep(&token, " "); + if ((val == NULL) || (strict_strtoul(val, 16, &nbr_channel) != 0)) + nbr_channel = MBOX_RX_CHAN; + + val = strsep(&token, " "); + if ((val == NULL) || (strict_strtoul(val, 16, &nbr_word) != 0)) + nbr_word = 2; + + dev_dbg(dev, "Will setup logical channel %ld\n", nbr_channel); + mboxtest.channel = nbr_channel; + mboxtest.words = nbr_word; + + if (!registration_done) + mboxtest_prepare(&mboxtest); + else + dev_dbg(&channels.pdev->dev, "already registration done\n"); + + return count; +} + +static ssize_t mbox_read_channel(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + + unsigned long i; + static bool config_done; + + if (!config_done) { + config_done = true; + mboxtest.channel += MBOX_TX_RX_CHANNEL_DIFF; + } + dev_dbg(dev, "Will transfer %d words %d times at channel 0x%x\n", + mboxtest.words, mboxtest.xfers, mboxtest.channel); + for (i = 0; i < mboxtest.xfers; i++) + transfer_test(&mboxtest); + + return 1; +} +static DEVICE_ATTR(channel, S_IWUGO | S_IRUGO, mbox_read_channel, + mbox_write_channel); + +#endif + +static int __init mbox_channel_probe(struct platform_device *pdev) +{ + int i, ret = 0; + struct mbox *mbox; + + dev_dbg(&(pdev->dev), "Probing mailbox (pdev = 0x%X)...\n", (u32)pdev); + + /* Register to given mailbox units (ids) */ + for (i = 0; i < ARRAY_SIZE(mbox_ids); i++) { + mbox = mbox_setup(mbox_ids[i], mbox_cb, &mbox_ids[i]); + if (mbox == NULL) { + dev_err(&(pdev->dev), "Unable to setup mailbox %d\n", + mbox_ids[i]); + ret = -EBUSY; + goto exit; + } + channels.mbox_unit[i].mbox_id = mbox_ids[i]; + channels.mbox_unit[i].mbox = mbox; + INIT_LIST_HEAD(&channels.mbox_unit[i].rx_chans); + INIT_LIST_HEAD(&channels.mbox_unit[i].tx_chans); + spin_lock_init(&channels.mbox_unit[i].rx_lock); + spin_lock_init(&channels.mbox_unit[i].tx_lock); + } + + channels.pdev = pdev; + + dev_dbg(&(pdev->dev), "Mailbox channel driver loaded\n"); +#if defined(CONFIG_DEBUG_FS) + ret = device_create_file(&(pdev->dev), &dev_attr_channel); + if (ret != 0) + dev_warn(&(pdev->dev), + "Unable to create mbox_channel sysfs entry"); + + +#endif +exit: + return ret; +} + +static struct platform_driver mbox_channel_driver = { + .driver = { + .name = "mbox_channel", + .owner = THIS_MODULE, + }, +}; + +static int __init mbox_channel_init(void) +{ + if (!machine_is_u5500()) + return 0; + + platform_device_register_simple("mbox_channel", 0, NULL, 0); + + return platform_driver_probe(&mbox_channel_driver, mbox_channel_probe); +} +module_init(mbox_channel_init); + +static void __exit mbox_channel_exit(void) +{ + platform_driver_unregister(&mbox_channel_driver); +} +module_exit(mbox_channel_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("MBOX channels driver"); |