+++ /dev/null
-/*
- * Copyright (c) 2015, Sony Mobile Communications AB.
- * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 and
- * only version 2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- */
-
-#include <linux/interrupt.h>
-#include <linux/io.h>
-#include <linux/mfd/syscon.h>
-#include <linux/module.h>
-#include <linux/of_irq.h>
-#include <linux/of_platform.h>
-#include <linux/platform_device.h>
-#include <linux/regmap.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <linux/soc/qcom/smd.h>
-#include <linux/soc/qcom/smem.h>
-#include <linux/wait.h>
-
-/*
- * The Qualcomm Shared Memory communication solution provides point-to-point
- * channels for clients to send and receive streaming or packet based data.
- *
- * Each channel consists of a control item (channel info) and a ring buffer
- * pair. The channel info carry information related to channel state, flow
- * control and the offsets within the ring buffer.
- *
- * All allocated channels are listed in an allocation table, identifying the
- * pair of items by name, type and remote processor.
- *
- * Upon creating a new channel the remote processor allocates channel info and
- * ring buffer items from the smem heap and populate the allocation table. An
- * interrupt is sent to the other end of the channel and a scan for new
- * channels should be done. A channel never goes away, it will only change
- * state.
- *
- * The remote processor signals it intent for bring up the communication
- * channel by setting the state of its end of the channel to "opening" and
- * sends out an interrupt. We detect this change and register a smd device to
- * consume the channel. Upon finding a consumer we finish the handshake and the
- * channel is up.
- *
- * Upon closing a channel, the remote processor will update the state of its
- * end of the channel and signal us, we will then unregister any attached
- * device and close our end of the channel.
- *
- * Devices attached to a channel can use the qcom_smd_send function to push
- * data to the channel, this is done by copying the data into the tx ring
- * buffer, updating the pointers in the channel info and signaling the remote
- * processor.
- *
- * The remote processor does the equivalent when it transfer data and upon
- * receiving the interrupt we check the channel info for new data and delivers
- * this to the attached device. If the device is not ready to receive the data
- * we leave it in the ring buffer for now.
- */
-
-struct smd_channel_info;
-struct smd_channel_info_pair;
-struct smd_channel_info_word;
-struct smd_channel_info_word_pair;
-
-#define SMD_ALLOC_TBL_COUNT 2
-#define SMD_ALLOC_TBL_SIZE 64
-
-/*
- * This lists the various smem heap items relevant for the allocation table and
- * smd channel entries.
- */
-static const struct {
- unsigned alloc_tbl_id;
- unsigned info_base_id;
- unsigned fifo_base_id;
-} smem_items[SMD_ALLOC_TBL_COUNT] = {
- {
- .alloc_tbl_id = 13,
- .info_base_id = 14,
- .fifo_base_id = 338
- },
- {
- .alloc_tbl_id = 266,
- .info_base_id = 138,
- .fifo_base_id = 202,
- },
-};
-
-/**
- * struct qcom_smd_edge - representing a remote processor
- * @dev: device for this edge
- * @of_node: of_node handle for information related to this edge
- * @edge_id: identifier of this edge
- * @remote_pid: identifier of remote processor
- * @irq: interrupt for signals on this edge
- * @ipc_regmap: regmap handle holding the outgoing ipc register
- * @ipc_offset: offset within @ipc_regmap of the register for ipc
- * @ipc_bit: bit in the register at @ipc_offset of @ipc_regmap
- * @channels: list of all channels detected on this edge
- * @channels_lock: guard for modifications of @channels
- * @allocated: array of bitmaps representing already allocated channels
- * @smem_available: last available amount of smem triggering a channel scan
- * @scan_work: work item for discovering new channels
- * @state_work: work item for edge state changes
- */
-struct qcom_smd_edge {
- struct device dev;
-
- struct device_node *of_node;
- unsigned edge_id;
- unsigned remote_pid;
-
- int irq;
-
- struct regmap *ipc_regmap;
- int ipc_offset;
- int ipc_bit;
-
- struct list_head channels;
- spinlock_t channels_lock;
-
- DECLARE_BITMAP(allocated[SMD_ALLOC_TBL_COUNT], SMD_ALLOC_TBL_SIZE);
-
- unsigned smem_available;
-
- wait_queue_head_t new_channel_event;
-
- struct work_struct scan_work;
- struct work_struct state_work;
-};
-
-#define to_smd_edge(d) container_of(d, struct qcom_smd_edge, dev)
-
-/*
- * SMD channel states.
- */
-enum smd_channel_state {
- SMD_CHANNEL_CLOSED,
- SMD_CHANNEL_OPENING,
- SMD_CHANNEL_OPENED,
- SMD_CHANNEL_FLUSHING,
- SMD_CHANNEL_CLOSING,
- SMD_CHANNEL_RESET,
- SMD_CHANNEL_RESET_OPENING
-};
-
-/**
- * struct qcom_smd_channel - smd channel struct
- * @edge: qcom_smd_edge this channel is living on
- * @qsdev: reference to a associated smd client device
- * @name: name of the channel
- * @state: local state of the channel
- * @remote_state: remote state of the channel
- * @info: byte aligned outgoing/incoming channel info
- * @info_word: word aligned outgoing/incoming channel info
- * @tx_lock: lock to make writes to the channel mutually exclusive
- * @fblockread_event: wakeup event tied to tx fBLOCKREADINTR
- * @tx_fifo: pointer to the outgoing ring buffer
- * @rx_fifo: pointer to the incoming ring buffer
- * @fifo_size: size of each ring buffer
- * @bounce_buffer: bounce buffer for reading wrapped packets
- * @cb: callback function registered for this channel
- * @recv_lock: guard for rx info modifications and cb pointer
- * @pkt_size: size of the currently handled packet
- * @list: lite entry for @channels in qcom_smd_edge
- */
-struct qcom_smd_channel {
- struct qcom_smd_edge *edge;
-
- struct qcom_smd_device *qsdev;
-
- char *name;
- enum smd_channel_state state;
- enum smd_channel_state remote_state;
-
- struct smd_channel_info_pair *info;
- struct smd_channel_info_word_pair *info_word;
-
- struct mutex tx_lock;
- wait_queue_head_t fblockread_event;
-
- void *tx_fifo;
- void *rx_fifo;
- int fifo_size;
-
- void *bounce_buffer;
- qcom_smd_cb_t cb;
-
- spinlock_t recv_lock;
-
- int pkt_size;
-
- void *drvdata;
-
- struct list_head list;
-};
-
-/*
- * Format of the smd_info smem items, for byte aligned channels.
- */
-struct smd_channel_info {
- __le32 state;
- u8 fDSR;
- u8 fCTS;
- u8 fCD;
- u8 fRI;
- u8 fHEAD;
- u8 fTAIL;
- u8 fSTATE;
- u8 fBLOCKREADINTR;
- __le32 tail;
- __le32 head;
-};
-
-struct smd_channel_info_pair {
- struct smd_channel_info tx;
- struct smd_channel_info rx;
-};
-
-/*
- * Format of the smd_info smem items, for word aligned channels.
- */
-struct smd_channel_info_word {
- __le32 state;
- __le32 fDSR;
- __le32 fCTS;
- __le32 fCD;
- __le32 fRI;
- __le32 fHEAD;
- __le32 fTAIL;
- __le32 fSTATE;
- __le32 fBLOCKREADINTR;
- __le32 tail;
- __le32 head;
-};
-
-struct smd_channel_info_word_pair {
- struct smd_channel_info_word tx;
- struct smd_channel_info_word rx;
-};
-
-#define GET_RX_CHANNEL_FLAG(channel, param) \
- ({ \
- BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u8)); \
- channel->info_word ? \
- le32_to_cpu(channel->info_word->rx.param) : \
- channel->info->rx.param; \
- })
-
-#define GET_RX_CHANNEL_INFO(channel, param) \
- ({ \
- BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u32)); \
- le32_to_cpu(channel->info_word ? \
- channel->info_word->rx.param : \
- channel->info->rx.param); \
- })
-
-#define SET_RX_CHANNEL_FLAG(channel, param, value) \
- ({ \
- BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u8)); \
- if (channel->info_word) \
- channel->info_word->rx.param = cpu_to_le32(value); \
- else \
- channel->info->rx.param = value; \
- })
-
-#define SET_RX_CHANNEL_INFO(channel, param, value) \
- ({ \
- BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u32)); \
- if (channel->info_word) \
- channel->info_word->rx.param = cpu_to_le32(value); \
- else \
- channel->info->rx.param = cpu_to_le32(value); \
- })
-
-#define GET_TX_CHANNEL_FLAG(channel, param) \
- ({ \
- BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u8)); \
- channel->info_word ? \
- le32_to_cpu(channel->info_word->tx.param) : \
- channel->info->tx.param; \
- })
-
-#define GET_TX_CHANNEL_INFO(channel, param) \
- ({ \
- BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u32)); \
- le32_to_cpu(channel->info_word ? \
- channel->info_word->tx.param : \
- channel->info->tx.param); \
- })
-
-#define SET_TX_CHANNEL_FLAG(channel, param, value) \
- ({ \
- BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u8)); \
- if (channel->info_word) \
- channel->info_word->tx.param = cpu_to_le32(value); \
- else \
- channel->info->tx.param = value; \
- })
-
-#define SET_TX_CHANNEL_INFO(channel, param, value) \
- ({ \
- BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u32)); \
- if (channel->info_word) \
- channel->info_word->tx.param = cpu_to_le32(value); \
- else \
- channel->info->tx.param = cpu_to_le32(value); \
- })
-
-/**
- * struct qcom_smd_alloc_entry - channel allocation entry
- * @name: channel name
- * @cid: channel index
- * @flags: channel flags and edge id
- * @ref_count: reference count of the channel
- */
-struct qcom_smd_alloc_entry {
- u8 name[20];
- __le32 cid;
- __le32 flags;
- __le32 ref_count;
-} __packed;
-
-#define SMD_CHANNEL_FLAGS_EDGE_MASK 0xff
-#define SMD_CHANNEL_FLAGS_STREAM BIT(8)
-#define SMD_CHANNEL_FLAGS_PACKET BIT(9)
-
-/*
- * Each smd packet contains a 20 byte header, with the first 4 being the length
- * of the packet.
- */
-#define SMD_PACKET_HEADER_LEN 20
-
-/*
- * Signal the remote processor associated with 'channel'.
- */
-static void qcom_smd_signal_channel(struct qcom_smd_channel *channel)
-{
- struct qcom_smd_edge *edge = channel->edge;
-
- regmap_write(edge->ipc_regmap, edge->ipc_offset, BIT(edge->ipc_bit));
-}
-
-/*
- * Initialize the tx channel info
- */
-static void qcom_smd_channel_reset(struct qcom_smd_channel *channel)
-{
- SET_TX_CHANNEL_INFO(channel, state, SMD_CHANNEL_CLOSED);
- SET_TX_CHANNEL_FLAG(channel, fDSR, 0);
- SET_TX_CHANNEL_FLAG(channel, fCTS, 0);
- SET_TX_CHANNEL_FLAG(channel, fCD, 0);
- SET_TX_CHANNEL_FLAG(channel, fRI, 0);
- SET_TX_CHANNEL_FLAG(channel, fHEAD, 0);
- SET_TX_CHANNEL_FLAG(channel, fTAIL, 0);
- SET_TX_CHANNEL_FLAG(channel, fSTATE, 1);
- SET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR, 1);
- SET_TX_CHANNEL_INFO(channel, head, 0);
- SET_RX_CHANNEL_INFO(channel, tail, 0);
-
- qcom_smd_signal_channel(channel);
-
- channel->state = SMD_CHANNEL_CLOSED;
- channel->pkt_size = 0;
-}
-
-/*
- * Set the callback for a channel, with appropriate locking
- */
-static void qcom_smd_channel_set_callback(struct qcom_smd_channel *channel,
- qcom_smd_cb_t cb)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&channel->recv_lock, flags);
- channel->cb = cb;
- spin_unlock_irqrestore(&channel->recv_lock, flags);
-};
-
-/*
- * Calculate the amount of data available in the rx fifo
- */
-static size_t qcom_smd_channel_get_rx_avail(struct qcom_smd_channel *channel)
-{
- unsigned head;
- unsigned tail;
-
- head = GET_RX_CHANNEL_INFO(channel, head);
- tail = GET_RX_CHANNEL_INFO(channel, tail);
-
- return (head - tail) & (channel->fifo_size - 1);
-}
-
-/*
- * Set tx channel state and inform the remote processor
- */
-static void qcom_smd_channel_set_state(struct qcom_smd_channel *channel,
- int state)
-{
- struct qcom_smd_edge *edge = channel->edge;
- bool is_open = state == SMD_CHANNEL_OPENED;
-
- if (channel->state == state)
- return;
-
- dev_dbg(&edge->dev, "set_state(%s, %d)\n", channel->name, state);
-
- SET_TX_CHANNEL_FLAG(channel, fDSR, is_open);
- SET_TX_CHANNEL_FLAG(channel, fCTS, is_open);
- SET_TX_CHANNEL_FLAG(channel, fCD, is_open);
-
- SET_TX_CHANNEL_INFO(channel, state, state);
- SET_TX_CHANNEL_FLAG(channel, fSTATE, 1);
-
- channel->state = state;
- qcom_smd_signal_channel(channel);
-}
-
-/*
- * Copy count bytes of data using 32bit accesses, if that's required.
- */
-static void smd_copy_to_fifo(void __iomem *dst,
- const void *src,
- size_t count,
- bool word_aligned)
-{
- if (word_aligned) {
- __iowrite32_copy(dst, src, count / sizeof(u32));
- } else {
- memcpy_toio(dst, src, count);
- }
-}
-
-/*
- * Copy count bytes of data using 32bit accesses, if that is required.
- */
-static void smd_copy_from_fifo(void *dst,
- const void __iomem *src,
- size_t count,
- bool word_aligned)
-{
- if (word_aligned) {
- __ioread32_copy(dst, src, count / sizeof(u32));
- } else {
- memcpy_fromio(dst, src, count);
- }
-}
-
-/*
- * Read count bytes of data from the rx fifo into buf, but don't advance the
- * tail.
- */
-static size_t qcom_smd_channel_peek(struct qcom_smd_channel *channel,
- void *buf, size_t count)
-{
- bool word_aligned;
- unsigned tail;
- size_t len;
-
- word_aligned = channel->info_word;
- tail = GET_RX_CHANNEL_INFO(channel, tail);
-
- len = min_t(size_t, count, channel->fifo_size - tail);
- if (len) {
- smd_copy_from_fifo(buf,
- channel->rx_fifo + tail,
- len,
- word_aligned);
- }
-
- if (len != count) {
- smd_copy_from_fifo(buf + len,
- channel->rx_fifo,
- count - len,
- word_aligned);
- }
-
- return count;
-}
-
-/*
- * Advance the rx tail by count bytes.
- */
-static void qcom_smd_channel_advance(struct qcom_smd_channel *channel,
- size_t count)
-{
- unsigned tail;
-
- tail = GET_RX_CHANNEL_INFO(channel, tail);
- tail += count;
- tail &= (channel->fifo_size - 1);
- SET_RX_CHANNEL_INFO(channel, tail, tail);
-}
-
-/*
- * Read out a single packet from the rx fifo and deliver it to the device
- */
-static int qcom_smd_channel_recv_single(struct qcom_smd_channel *channel)
-{
- unsigned tail;
- size_t len;
- void *ptr;
- int ret;
-
- if (!channel->cb)
- return 0;
-
- tail = GET_RX_CHANNEL_INFO(channel, tail);
-
- /* Use bounce buffer if the data wraps */
- if (tail + channel->pkt_size >= channel->fifo_size) {
- ptr = channel->bounce_buffer;
- len = qcom_smd_channel_peek(channel, ptr, channel->pkt_size);
- } else {
- ptr = channel->rx_fifo + tail;
- len = channel->pkt_size;
- }
-
- ret = channel->cb(channel, ptr, len);
- if (ret < 0)
- return ret;
-
- /* Only forward the tail if the client consumed the data */
- qcom_smd_channel_advance(channel, len);
-
- channel->pkt_size = 0;
-
- return 0;
-}
-
-/*
- * Per channel interrupt handling
- */
-static bool qcom_smd_channel_intr(struct qcom_smd_channel *channel)
-{
- bool need_state_scan = false;
- int remote_state;
- __le32 pktlen;
- int avail;
- int ret;
-
- /* Handle state changes */
- remote_state = GET_RX_CHANNEL_INFO(channel, state);
- if (remote_state != channel->remote_state) {
- channel->remote_state = remote_state;
- need_state_scan = true;
- }
- /* Indicate that we have seen any state change */
- SET_RX_CHANNEL_FLAG(channel, fSTATE, 0);
-
- /* Signal waiting qcom_smd_send() about the interrupt */
- if (!GET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR))
- wake_up_interruptible(&channel->fblockread_event);
-
- /* Don't consume any data until we've opened the channel */
- if (channel->state != SMD_CHANNEL_OPENED)
- goto out;
-
- /* Indicate that we've seen the new data */
- SET_RX_CHANNEL_FLAG(channel, fHEAD, 0);
-
- /* Consume data */
- for (;;) {
- avail = qcom_smd_channel_get_rx_avail(channel);
-
- if (!channel->pkt_size && avail >= SMD_PACKET_HEADER_LEN) {
- qcom_smd_channel_peek(channel, &pktlen, sizeof(pktlen));
- qcom_smd_channel_advance(channel, SMD_PACKET_HEADER_LEN);
- channel->pkt_size = le32_to_cpu(pktlen);
- } else if (channel->pkt_size && avail >= channel->pkt_size) {
- ret = qcom_smd_channel_recv_single(channel);
- if (ret)
- break;
- } else {
- break;
- }
- }
-
- /* Indicate that we have seen and updated tail */
- SET_RX_CHANNEL_FLAG(channel, fTAIL, 1);
-
- /* Signal the remote that we've consumed the data (if requested) */
- if (!GET_RX_CHANNEL_FLAG(channel, fBLOCKREADINTR)) {
- /* Ensure ordering of channel info updates */
- wmb();
-
- qcom_smd_signal_channel(channel);
- }
-
-out:
- return need_state_scan;
-}
-
-/*
- * The edge interrupts are triggered by the remote processor on state changes,
- * channel info updates or when new channels are created.
- */
-static irqreturn_t qcom_smd_edge_intr(int irq, void *data)
-{
- struct qcom_smd_edge *edge = data;
- struct qcom_smd_channel *channel;
- unsigned available;
- bool kick_scanner = false;
- bool kick_state = false;
-
- /*
- * Handle state changes or data on each of the channels on this edge
- */
- spin_lock(&edge->channels_lock);
- list_for_each_entry(channel, &edge->channels, list) {
- spin_lock(&channel->recv_lock);
- kick_state |= qcom_smd_channel_intr(channel);
- spin_unlock(&channel->recv_lock);
- }
- spin_unlock(&edge->channels_lock);
-
- /*
- * Creating a new channel requires allocating an smem entry, so we only
- * have to scan if the amount of available space in smem have changed
- * since last scan.
- */
- available = qcom_smem_get_free_space(edge->remote_pid);
- if (available != edge->smem_available) {
- edge->smem_available = available;
- kick_scanner = true;
- }
-
- if (kick_scanner)
- schedule_work(&edge->scan_work);
- if (kick_state)
- schedule_work(&edge->state_work);
-
- return IRQ_HANDLED;
-}
-
-/*
- * Delivers any outstanding packets in the rx fifo, can be used after probe of
- * the clients to deliver any packets that wasn't delivered before the client
- * was setup.
- */
-static void qcom_smd_channel_resume(struct qcom_smd_channel *channel)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&channel->recv_lock, flags);
- qcom_smd_channel_intr(channel);
- spin_unlock_irqrestore(&channel->recv_lock, flags);
-}
-
-/*
- * Calculate how much space is available in the tx fifo.
- */
-static size_t qcom_smd_get_tx_avail(struct qcom_smd_channel *channel)
-{
- unsigned head;
- unsigned tail;
- unsigned mask = channel->fifo_size - 1;
-
- head = GET_TX_CHANNEL_INFO(channel, head);
- tail = GET_TX_CHANNEL_INFO(channel, tail);
-
- return mask - ((head - tail) & mask);
-}
-
-/*
- * Write count bytes of data into channel, possibly wrapping in the ring buffer
- */
-static int qcom_smd_write_fifo(struct qcom_smd_channel *channel,
- const void *data,
- size_t count)
-{
- bool word_aligned;
- unsigned head;
- size_t len;
-
- word_aligned = channel->info_word;
- head = GET_TX_CHANNEL_INFO(channel, head);
-
- len = min_t(size_t, count, channel->fifo_size - head);
- if (len) {
- smd_copy_to_fifo(channel->tx_fifo + head,
- data,
- len,
- word_aligned);
- }
-
- if (len != count) {
- smd_copy_to_fifo(channel->tx_fifo,
- data + len,
- count - len,
- word_aligned);
- }
-
- head += count;
- head &= (channel->fifo_size - 1);
- SET_TX_CHANNEL_INFO(channel, head, head);
-
- return count;
-}
-
-/**
- * qcom_smd_send - write data to smd channel
- * @channel: channel handle
- * @data: buffer of data to write
- * @len: number of bytes to write
- *
- * This is a blocking write of len bytes into the channel's tx ring buffer and
- * signal the remote end. It will sleep until there is enough space available
- * in the tx buffer, utilizing the fBLOCKREADINTR signaling mechanism to avoid
- * polling.
- */
-int qcom_smd_send(struct qcom_smd_channel *channel, const void *data, int len)
-{
- __le32 hdr[5] = { cpu_to_le32(len), };
- int tlen = sizeof(hdr) + len;
- int ret;
-
- /* Word aligned channels only accept word size aligned data */
- if (channel->info_word && len % 4)
- return -EINVAL;
-
- /* Reject packets that are too big */
- if (tlen >= channel->fifo_size)
- return -EINVAL;
-
- ret = mutex_lock_interruptible(&channel->tx_lock);
- if (ret)
- return ret;
-
- while (qcom_smd_get_tx_avail(channel) < tlen) {
- if (channel->state != SMD_CHANNEL_OPENED) {
- ret = -EPIPE;
- goto out;
- }
-
- SET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR, 0);
-
- ret = wait_event_interruptible(channel->fblockread_event,
- qcom_smd_get_tx_avail(channel) >= tlen ||
- channel->state != SMD_CHANNEL_OPENED);
- if (ret)
- goto out;
-
- SET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR, 1);
- }
-
- SET_TX_CHANNEL_FLAG(channel, fTAIL, 0);
-
- qcom_smd_write_fifo(channel, hdr, sizeof(hdr));
- qcom_smd_write_fifo(channel, data, len);
-
- SET_TX_CHANNEL_FLAG(channel, fHEAD, 1);
-
- /* Ensure ordering of channel info updates */
- wmb();
-
- qcom_smd_signal_channel(channel);
-
-out:
- mutex_unlock(&channel->tx_lock);
-
- return ret;
-}
-EXPORT_SYMBOL(qcom_smd_send);
-
-static struct qcom_smd_device *to_smd_device(struct device *dev)
-{
- return container_of(dev, struct qcom_smd_device, dev);
-}
-
-static struct qcom_smd_driver *to_smd_driver(struct device *dev)
-{
- struct qcom_smd_device *qsdev = to_smd_device(dev);
-
- return container_of(qsdev->dev.driver, struct qcom_smd_driver, driver);
-}
-
-static int qcom_smd_dev_match(struct device *dev, struct device_driver *drv)
-{
- struct qcom_smd_device *qsdev = to_smd_device(dev);
- struct qcom_smd_driver *qsdrv = container_of(drv, struct qcom_smd_driver, driver);
- const struct qcom_smd_id *match = qsdrv->smd_match_table;
- const char *name = qsdev->channel->name;
-
- if (match) {
- while (match->name[0]) {
- if (!strcmp(match->name, name))
- return 1;
- match++;
- }
- }
-
- return of_driver_match_device(dev, drv);
-}
-
-/*
- * Helper for opening a channel
- */
-static int qcom_smd_channel_open(struct qcom_smd_channel *channel,
- qcom_smd_cb_t cb)
-{
- size_t bb_size;
-
- /*
- * Packets are maximum 4k, but reduce if the fifo is smaller
- */
- bb_size = min(channel->fifo_size, SZ_4K);
- channel->bounce_buffer = kmalloc(bb_size, GFP_KERNEL);
- if (!channel->bounce_buffer)
- return -ENOMEM;
-
- qcom_smd_channel_set_callback(channel, cb);
- qcom_smd_channel_set_state(channel, SMD_CHANNEL_OPENING);
- qcom_smd_channel_set_state(channel, SMD_CHANNEL_OPENED);
-
- return 0;
-}
-
-/*
- * Helper for closing and resetting a channel
- */
-static void qcom_smd_channel_close(struct qcom_smd_channel *channel)
-{
- qcom_smd_channel_set_callback(channel, NULL);
-
- kfree(channel->bounce_buffer);
- channel->bounce_buffer = NULL;
-
- qcom_smd_channel_set_state(channel, SMD_CHANNEL_CLOSED);
- qcom_smd_channel_reset(channel);
-}
-
-/*
- * Probe the smd client.
- *
- * The remote side have indicated that it want the channel to be opened, so
- * complete the state handshake and probe our client driver.
- */
-static int qcom_smd_dev_probe(struct device *dev)
-{
- struct qcom_smd_device *qsdev = to_smd_device(dev);
- struct qcom_smd_driver *qsdrv = to_smd_driver(dev);
- struct qcom_smd_channel *channel = qsdev->channel;
- int ret;
-
- ret = qcom_smd_channel_open(channel, qsdrv->callback);
- if (ret)
- return ret;
-
- ret = qsdrv->probe(qsdev);
- if (ret)
- goto err;
-
- qcom_smd_channel_resume(channel);
-
- return 0;
-
-err:
- dev_err(&qsdev->dev, "probe failed\n");
-
- qcom_smd_channel_close(channel);
- return ret;
-}
-
-/*
- * Remove the smd client.
- *
- * The channel is going away, for some reason, so remove the smd client and
- * reset the channel state.
- */
-static int qcom_smd_dev_remove(struct device *dev)
-{
- struct qcom_smd_device *qsdev = to_smd_device(dev);
- struct qcom_smd_driver *qsdrv = to_smd_driver(dev);
- struct qcom_smd_channel *channel = qsdev->channel;
-
- qcom_smd_channel_set_state(channel, SMD_CHANNEL_CLOSING);
-
- /*
- * Make sure we don't race with the code receiving data.
- */
- qcom_smd_channel_set_callback(channel, NULL);
-
- /* Wake up any sleepers in qcom_smd_send() */
- wake_up_interruptible(&channel->fblockread_event);
-
- /*
- * We expect that the client might block in remove() waiting for any
- * outstanding calls to qcom_smd_send() to wake up and finish.
- */
- if (qsdrv->remove)
- qsdrv->remove(qsdev);
-
- /* The client is now gone, close the primary channel */
- qcom_smd_channel_close(channel);
- channel->qsdev = NULL;
-
- return 0;
-}
-
-static struct bus_type qcom_smd_bus = {
- .name = "qcom_smd",
- .match = qcom_smd_dev_match,
- .probe = qcom_smd_dev_probe,
- .remove = qcom_smd_dev_remove,
-};
-
-/*
- * Release function for the qcom_smd_device object.
- */
-static void qcom_smd_release_device(struct device *dev)
-{
- struct qcom_smd_device *qsdev = to_smd_device(dev);
-
- kfree(qsdev);
-}
-
-/*
- * Finds the device_node for the smd child interested in this channel.
- */
-static struct device_node *qcom_smd_match_channel(struct device_node *edge_node,
- const char *channel)
-{
- struct device_node *child;
- const char *name;
- const char *key;
- int ret;
-
- for_each_available_child_of_node(edge_node, child) {
- key = "qcom,smd-channels";
- ret = of_property_read_string(child, key, &name);
- if (ret)
- continue;
-
- if (strcmp(name, channel) == 0)
- return child;
- }
-
- return NULL;
-}
-
-/*
- * Create a smd client device for channel that is being opened.
- */
-static int qcom_smd_create_device(struct qcom_smd_channel *channel)
-{
- struct qcom_smd_device *qsdev;
- struct qcom_smd_edge *edge = channel->edge;
- struct device_node *node;
- int ret;
-
- if (channel->qsdev)
- return -EEXIST;
-
- dev_dbg(&edge->dev, "registering '%s'\n", channel->name);
-
- qsdev = kzalloc(sizeof(*qsdev), GFP_KERNEL);
- if (!qsdev)
- return -ENOMEM;
-
- node = qcom_smd_match_channel(edge->of_node, channel->name);
- dev_set_name(&qsdev->dev, "%s.%s",
- edge->of_node->name,
- node ? node->name : channel->name);
-
- qsdev->dev.parent = &edge->dev;
- qsdev->dev.bus = &qcom_smd_bus;
- qsdev->dev.release = qcom_smd_release_device;
- qsdev->dev.of_node = node;
-
- qsdev->channel = channel;
-
- channel->qsdev = qsdev;
-
- ret = device_register(&qsdev->dev);
- if (ret) {
- dev_err(&edge->dev, "device_register failed: %d\n", ret);
- put_device(&qsdev->dev);
- }
-
- return ret;
-}
-
-/*
- * Destroy a smd client device for a channel that's going away.
- */
-static void qcom_smd_destroy_device(struct qcom_smd_channel *channel)
-{
- struct device *dev;
-
- BUG_ON(!channel->qsdev);
-
- dev = &channel->qsdev->dev;
-
- device_unregister(dev);
- of_node_put(dev->of_node);
- put_device(dev);
-}
-
-/**
- * qcom_smd_driver_register - register a smd driver
- * @qsdrv: qcom_smd_driver struct
- */
-int qcom_smd_driver_register(struct qcom_smd_driver *qsdrv)
-{
- qsdrv->driver.bus = &qcom_smd_bus;
- return driver_register(&qsdrv->driver);
-}
-EXPORT_SYMBOL(qcom_smd_driver_register);
-
-void *qcom_smd_get_drvdata(struct qcom_smd_channel *channel)
-{
- return channel->drvdata;
-}
-EXPORT_SYMBOL(qcom_smd_get_drvdata);
-
-void qcom_smd_set_drvdata(struct qcom_smd_channel *channel, void *data)
-{
- channel->drvdata = data;
-}
-EXPORT_SYMBOL(qcom_smd_set_drvdata);
-
-/**
- * qcom_smd_driver_unregister - unregister a smd driver
- * @qsdrv: qcom_smd_driver struct
- */
-void qcom_smd_driver_unregister(struct qcom_smd_driver *qsdrv)
-{
- driver_unregister(&qsdrv->driver);
-}
-EXPORT_SYMBOL(qcom_smd_driver_unregister);
-
-static struct qcom_smd_channel *
-qcom_smd_find_channel(struct qcom_smd_edge *edge, const char *name)
-{
- struct qcom_smd_channel *channel;
- struct qcom_smd_channel *ret = NULL;
- unsigned long flags;
- unsigned state;
-
- spin_lock_irqsave(&edge->channels_lock, flags);
- list_for_each_entry(channel, &edge->channels, list) {
- if (strcmp(channel->name, name))
- continue;
-
- state = GET_RX_CHANNEL_INFO(channel, state);
- if (state != SMD_CHANNEL_OPENING &&
- state != SMD_CHANNEL_OPENED)
- continue;
-
- ret = channel;
- break;
- }
- spin_unlock_irqrestore(&edge->channels_lock, flags);
-
- return ret;
-}
-
-/**
- * qcom_smd_open_channel() - claim additional channels on the same edge
- * @sdev: smd_device handle
- * @name: channel name
- * @cb: callback method to use for incoming data
- *
- * Returns a channel handle on success, or -EPROBE_DEFER if the channel isn't
- * ready.
- *
- * Any channels returned must be closed with a call to qcom_smd_close_channel()
- */
-struct qcom_smd_channel *qcom_smd_open_channel(struct qcom_smd_channel *parent,
- const char *name,
- qcom_smd_cb_t cb)
-{
- struct qcom_smd_channel *channel;
- struct qcom_smd_device *sdev = parent->qsdev;
- struct qcom_smd_edge *edge = parent->edge;
- int ret;
-
- /* Wait up to HZ for the channel to appear */
- ret = wait_event_interruptible_timeout(edge->new_channel_event,
- (channel = qcom_smd_find_channel(edge, name)) != NULL,
- HZ);
- if (!ret)
- return ERR_PTR(-ETIMEDOUT);
-
- if (channel->state != SMD_CHANNEL_CLOSED) {
- dev_err(&sdev->dev, "channel %s is busy\n", channel->name);
- return ERR_PTR(-EBUSY);
- }
-
- channel->qsdev = sdev;
- ret = qcom_smd_channel_open(channel, cb);
- if (ret) {
- channel->qsdev = NULL;
- return ERR_PTR(ret);
- }
-
- return channel;
-}
-EXPORT_SYMBOL(qcom_smd_open_channel);
-
-/**
- * qcom_smd_close_channel() - close an additionally opened channel
- * @channel: channel handle, returned by qcom_smd_open_channel()
- */
-void qcom_smd_close_channel(struct qcom_smd_channel *channel)
-{
- qcom_smd_channel_close(channel);
- channel->qsdev = NULL;
-}
-EXPORT_SYMBOL(qcom_smd_close_channel);
-
-/*
- * Allocate the qcom_smd_channel object for a newly found smd channel,
- * retrieving and validating the smem items involved.
- */
-static struct qcom_smd_channel *qcom_smd_create_channel(struct qcom_smd_edge *edge,
- unsigned smem_info_item,
- unsigned smem_fifo_item,
- char *name)
-{
- struct qcom_smd_channel *channel;
- size_t fifo_size;
- size_t info_size;
- void *fifo_base;
- void *info;
- int ret;
-
- channel = devm_kzalloc(&edge->dev, sizeof(*channel), GFP_KERNEL);
- if (!channel)
- return ERR_PTR(-ENOMEM);
-
- channel->edge = edge;
- channel->name = devm_kstrdup(&edge->dev, name, GFP_KERNEL);
- if (!channel->name)
- return ERR_PTR(-ENOMEM);
-
- mutex_init(&channel->tx_lock);
- spin_lock_init(&channel->recv_lock);
- init_waitqueue_head(&channel->fblockread_event);
-
- info = qcom_smem_get(edge->remote_pid, smem_info_item, &info_size);
- if (IS_ERR(info)) {
- ret = PTR_ERR(info);
- goto free_name_and_channel;
- }
-
- /*
- * Use the size of the item to figure out which channel info struct to
- * use.
- */
- if (info_size == 2 * sizeof(struct smd_channel_info_word)) {
- channel->info_word = info;
- } else if (info_size == 2 * sizeof(struct smd_channel_info)) {
- channel->info = info;
- } else {
- dev_err(&edge->dev,
- "channel info of size %zu not supported\n", info_size);
- ret = -EINVAL;
- goto free_name_and_channel;
- }
-
- fifo_base = qcom_smem_get(edge->remote_pid, smem_fifo_item, &fifo_size);
- if (IS_ERR(fifo_base)) {
- ret = PTR_ERR(fifo_base);
- goto free_name_and_channel;
- }
-
- /* The channel consist of a rx and tx fifo of equal size */
- fifo_size /= 2;
-
- dev_dbg(&edge->dev, "new channel '%s' info-size: %zu fifo-size: %zu\n",
- name, info_size, fifo_size);
-
- channel->tx_fifo = fifo_base;
- channel->rx_fifo = fifo_base + fifo_size;
- channel->fifo_size = fifo_size;
-
- qcom_smd_channel_reset(channel);
-
- return channel;
-
-free_name_and_channel:
- devm_kfree(&edge->dev, channel->name);
- devm_kfree(&edge->dev, channel);
-
- return ERR_PTR(ret);
-}
-
-/*
- * Scans the allocation table for any newly allocated channels, calls
- * qcom_smd_create_channel() to create representations of these and add
- * them to the edge's list of channels.
- */
-static void qcom_channel_scan_worker(struct work_struct *work)
-{
- struct qcom_smd_edge *edge = container_of(work, struct qcom_smd_edge, scan_work);
- struct qcom_smd_alloc_entry *alloc_tbl;
- struct qcom_smd_alloc_entry *entry;
- struct qcom_smd_channel *channel;
- unsigned long flags;
- unsigned fifo_id;
- unsigned info_id;
- int tbl;
- int i;
- u32 eflags, cid;
-
- for (tbl = 0; tbl < SMD_ALLOC_TBL_COUNT; tbl++) {
- alloc_tbl = qcom_smem_get(edge->remote_pid,
- smem_items[tbl].alloc_tbl_id, NULL);
- if (IS_ERR(alloc_tbl))
- continue;
-
- for (i = 0; i < SMD_ALLOC_TBL_SIZE; i++) {
- entry = &alloc_tbl[i];
- eflags = le32_to_cpu(entry->flags);
- if (test_bit(i, edge->allocated[tbl]))
- continue;
-
- if (entry->ref_count == 0)
- continue;
-
- if (!entry->name[0])
- continue;
-
- if (!(eflags & SMD_CHANNEL_FLAGS_PACKET))
- continue;
-
- if ((eflags & SMD_CHANNEL_FLAGS_EDGE_MASK) != edge->edge_id)
- continue;
-
- cid = le32_to_cpu(entry->cid);
- info_id = smem_items[tbl].info_base_id + cid;
- fifo_id = smem_items[tbl].fifo_base_id + cid;
-
- channel = qcom_smd_create_channel(edge, info_id, fifo_id, entry->name);
- if (IS_ERR(channel))
- continue;
-
- spin_lock_irqsave(&edge->channels_lock, flags);
- list_add(&channel->list, &edge->channels);
- spin_unlock_irqrestore(&edge->channels_lock, flags);
-
- dev_dbg(&edge->dev, "new channel found: '%s'\n", channel->name);
- set_bit(i, edge->allocated[tbl]);
-
- wake_up_interruptible(&edge->new_channel_event);
- }
- }
-
- schedule_work(&edge->state_work);
-}
-
-/*
- * This per edge worker scans smem for any new channels and register these. It
- * then scans all registered channels for state changes that should be handled
- * by creating or destroying smd client devices for the registered channels.
- *
- * LOCKING: edge->channels_lock only needs to cover the list operations, as the
- * worker is killed before any channels are deallocated
- */
-static void qcom_channel_state_worker(struct work_struct *work)
-{
- struct qcom_smd_channel *channel;
- struct qcom_smd_edge *edge = container_of(work,
- struct qcom_smd_edge,
- state_work);
- unsigned remote_state;
- unsigned long flags;
-
- /*
- * Register a device for any closed channel where the remote processor
- * is showing interest in opening the channel.
- */
- spin_lock_irqsave(&edge->channels_lock, flags);
- list_for_each_entry(channel, &edge->channels, list) {
- if (channel->state != SMD_CHANNEL_CLOSED)
- continue;
-
- remote_state = GET_RX_CHANNEL_INFO(channel, state);
- if (remote_state != SMD_CHANNEL_OPENING &&
- remote_state != SMD_CHANNEL_OPENED)
- continue;
-
- spin_unlock_irqrestore(&edge->channels_lock, flags);
- qcom_smd_create_device(channel);
- spin_lock_irqsave(&edge->channels_lock, flags);
- }
-
- /*
- * Unregister the device for any channel that is opened where the
- * remote processor is closing the channel.
- */
- list_for_each_entry(channel, &edge->channels, list) {
- if (channel->state != SMD_CHANNEL_OPENING &&
- channel->state != SMD_CHANNEL_OPENED)
- continue;
-
- remote_state = GET_RX_CHANNEL_INFO(channel, state);
- if (remote_state == SMD_CHANNEL_OPENING ||
- remote_state == SMD_CHANNEL_OPENED)
- continue;
-
- spin_unlock_irqrestore(&edge->channels_lock, flags);
- qcom_smd_destroy_device(channel);
- spin_lock_irqsave(&edge->channels_lock, flags);
- }
- spin_unlock_irqrestore(&edge->channels_lock, flags);
-}
-
-/*
- * Parses an of_node describing an edge.
- */
-static int qcom_smd_parse_edge(struct device *dev,
- struct device_node *node,
- struct qcom_smd_edge *edge)
-{
- struct device_node *syscon_np;
- const char *key;
- int irq;
- int ret;
-
- INIT_LIST_HEAD(&edge->channels);
- spin_lock_init(&edge->channels_lock);
-
- INIT_WORK(&edge->scan_work, qcom_channel_scan_worker);
- INIT_WORK(&edge->state_work, qcom_channel_state_worker);
-
- edge->of_node = of_node_get(node);
-
- key = "qcom,smd-edge";
- ret = of_property_read_u32(node, key, &edge->edge_id);
- if (ret) {
- dev_err(dev, "edge missing %s property\n", key);
- return -EINVAL;
- }
-
- edge->remote_pid = QCOM_SMEM_HOST_ANY;
- key = "qcom,remote-pid";
- of_property_read_u32(node, key, &edge->remote_pid);
-
- syscon_np = of_parse_phandle(node, "qcom,ipc", 0);
- if (!syscon_np) {
- dev_err(dev, "no qcom,ipc node\n");
- return -ENODEV;
- }
-
- edge->ipc_regmap = syscon_node_to_regmap(syscon_np);
- if (IS_ERR(edge->ipc_regmap))
- return PTR_ERR(edge->ipc_regmap);
-
- key = "qcom,ipc";
- ret = of_property_read_u32_index(node, key, 1, &edge->ipc_offset);
- if (ret < 0) {
- dev_err(dev, "no offset in %s\n", key);
- return -EINVAL;
- }
-
- ret = of_property_read_u32_index(node, key, 2, &edge->ipc_bit);
- if (ret < 0) {
- dev_err(dev, "no bit in %s\n", key);
- return -EINVAL;
- }
-
- irq = irq_of_parse_and_map(node, 0);
- if (irq < 0) {
- dev_err(dev, "required smd interrupt missing\n");
- return -EINVAL;
- }
-
- ret = devm_request_irq(dev, irq,
- qcom_smd_edge_intr, IRQF_TRIGGER_RISING,
- node->name, edge);
- if (ret) {
- dev_err(dev, "failed to request smd irq\n");
- return ret;
- }
-
- edge->irq = irq;
-
- return 0;
-}
-
-/*
- * Release function for an edge.
- * Reset the state of each associated channel and free the edge context.
- */
-static void qcom_smd_edge_release(struct device *dev)
-{
- struct qcom_smd_channel *channel;
- struct qcom_smd_edge *edge = to_smd_edge(dev);
-
- list_for_each_entry(channel, &edge->channels, list) {
- SET_RX_CHANNEL_INFO(channel, state, SMD_CHANNEL_CLOSED);
- SET_RX_CHANNEL_INFO(channel, head, 0);
- SET_RX_CHANNEL_INFO(channel, tail, 0);
- }
-
- kfree(edge);
-}
-
-/**
- * qcom_smd_register_edge() - register an edge based on an device_node
- * @parent: parent device for the edge
- * @node: device_node describing the edge
- *
- * Returns an edge reference, or negative ERR_PTR() on failure.
- */
-struct qcom_smd_edge *qcom_smd_register_edge(struct device *parent,
- struct device_node *node)
-{
- struct qcom_smd_edge *edge;
- int ret;
-
- edge = kzalloc(sizeof(*edge), GFP_KERNEL);
- if (!edge)
- return ERR_PTR(-ENOMEM);
-
- init_waitqueue_head(&edge->new_channel_event);
-
- edge->dev.parent = parent;
- edge->dev.release = qcom_smd_edge_release;
- dev_set_name(&edge->dev, "%s:%s", dev_name(parent), node->name);
- ret = device_register(&edge->dev);
- if (ret) {
- pr_err("failed to register smd edge\n");
- return ERR_PTR(ret);
- }
-
- ret = qcom_smd_parse_edge(&edge->dev, node, edge);
- if (ret) {
- dev_err(&edge->dev, "failed to parse smd edge\n");
- goto unregister_dev;
- }
-
- schedule_work(&edge->scan_work);
-
- return edge;
-
-unregister_dev:
- put_device(&edge->dev);
- return ERR_PTR(ret);
-}
-EXPORT_SYMBOL(qcom_smd_register_edge);
-
-static int qcom_smd_remove_device(struct device *dev, void *data)
-{
- device_unregister(dev);
- of_node_put(dev->of_node);
- put_device(dev);
-
- return 0;
-}
-
-/**
- * qcom_smd_unregister_edge() - release an edge and its children
- * @edge: edge reference acquired from qcom_smd_register_edge
- */
-int qcom_smd_unregister_edge(struct qcom_smd_edge *edge)
-{
- int ret;
-
- disable_irq(edge->irq);
- cancel_work_sync(&edge->scan_work);
- cancel_work_sync(&edge->state_work);
-
- ret = device_for_each_child(&edge->dev, NULL, qcom_smd_remove_device);
- if (ret)
- dev_warn(&edge->dev, "can't remove smd device: %d\n", ret);
-
- device_unregister(&edge->dev);
-
- return 0;
-}
-EXPORT_SYMBOL(qcom_smd_unregister_edge);
-
-static int qcom_smd_probe(struct platform_device *pdev)
-{
- struct device_node *node;
- void *p;
-
- /* Wait for smem */
- p = qcom_smem_get(QCOM_SMEM_HOST_ANY, smem_items[0].alloc_tbl_id, NULL);
- if (PTR_ERR(p) == -EPROBE_DEFER)
- return PTR_ERR(p);
-
- for_each_available_child_of_node(pdev->dev.of_node, node)
- qcom_smd_register_edge(&pdev->dev, node);
-
- return 0;
-}
-
-static int qcom_smd_remove_edge(struct device *dev, void *data)
-{
- struct qcom_smd_edge *edge = to_smd_edge(dev);
-
- return qcom_smd_unregister_edge(edge);
-}
-
-/*
- * Shut down all smd clients by making sure that each edge stops processing
- * events and scanning for new channels, then call destroy on the devices.
- */
-static int qcom_smd_remove(struct platform_device *pdev)
-{
- int ret;
-
- ret = device_for_each_child(&pdev->dev, NULL, qcom_smd_remove_edge);
- if (ret)
- dev_warn(&pdev->dev, "can't remove smd device: %d\n", ret);
-
- return ret;
-}
-
-static const struct of_device_id qcom_smd_of_match[] = {
- { .compatible = "qcom,smd" },
- {}
-};
-MODULE_DEVICE_TABLE(of, qcom_smd_of_match);
-
-static struct platform_driver qcom_smd_driver = {
- .probe = qcom_smd_probe,
- .remove = qcom_smd_remove,
- .driver = {
- .name = "qcom-smd",
- .of_match_table = qcom_smd_of_match,
- },
-};
-
-static int __init qcom_smd_init(void)
-{
- int ret;
-
- ret = bus_register(&qcom_smd_bus);
- if (ret) {
- pr_err("failed to register smd bus: %d\n", ret);
- return ret;
- }
-
- return platform_driver_register(&qcom_smd_driver);
-}
-postcore_initcall(qcom_smd_init);
-
-static void __exit qcom_smd_exit(void)
-{
- platform_driver_unregister(&qcom_smd_driver);
- bus_unregister(&qcom_smd_bus);
-}
-module_exit(qcom_smd_exit);
-
-MODULE_AUTHOR("Bjorn Andersson <bjorn.andersson@sonymobile.com>");
-MODULE_DESCRIPTION("Qualcomm Shared Memory Driver");
-MODULE_LICENSE("GPL v2");
projects / GitHub / MotorolaMobilityLLC / kernel-slsi.git / commitdiff