[06/14] soundwire: Add IO transfer

Message ID	1508382211-3154-7-git-send-email-vinod.koul@intel.com (mailing list archive)
State	New, archived
Headers	show Return-Path: <alsa-devel-bounces@alsa-project.org> From: Vinod Koul <vinod.koul@intel.com> To: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Date: Thu, 19 Oct 2017 08:33:22 +0530 Message-Id: <1508382211-3154-7-git-send-email-vinod.koul@intel.com> In-Reply-To: <1508382211-3154-1-git-send-email-vinod.koul@intel.com> References: <1508382211-3154-1-git-send-email-vinod.koul@intel.com> Cc: ALSA <alsa-devel@alsa-project.org>, Charles Keepax <ckeepax@opensource.cirrus.com>, Sudheer Papothi <spapothi@codeaurora.org>, Takashi <tiwai@suse.de>, plai@codeaurora.org, LKML <linux-kernel@vger.kernel.org>, Pierre <pierre-louis.bossart@linux.intel.com>, patches.audio@intel.com, Mark <broonie@kernel.org>, srinivas.kandagatla@linaro.org, Shreyas NC <shreyas.nc@intel.com>, Sanyog Kale <sanyog.r.kale@intel.com>, Sagar Dharia <sdharia@codeaurora.org>, alan@linux.intel.com Subject: [alsa-devel] [PATCH 06/14] soundwire: Add IO transfer Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org

diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c index 5b13d96b67b8..9ac22eab11bb 100644 --- a/drivers/soundwire/bus.c +++ b/drivers/soundwire/bus.c @@ -73,6 +73,12 @@ int sdw_add_bus_master(struct sdw_bus *bus) return -ENODEV; } + if (!bus->ops) { + dev_err(bus->dev, "SoundWire Bus ops are not set"); + return -EINVAL; + } + + mutex_init(&bus->msg_lock); mutex_init(&bus->bus_lock); INIT_LIST_HEAD(&bus->slaves); @@ -128,6 +134,265 @@ void sdw_delete_bus_master(struct sdw_bus *bus) } EXPORT_SYMBOL(sdw_delete_bus_master); +/* + * SDW IO Calls + */ + +static bool sdw_get_page(struct sdw_slave *slave, struct sdw_msg *msg) +{ + bool page = false, paging_support = false; + + if (slave && slave->prop.paging_support) + paging_support = true; + + /* + * Programme SCP page addr for: + * 1. addr_page1 and addr_page2 contains non-zero values. + * 2. Paging supported by Slave. + */ + switch (msg->dev_num) { + case SDW_ENUM_DEV_NUM: + case SDW_BROADCAST_DEV_NUM: + break; + + default: + if (paging_support && ((msg->addr_page1) || (msg->addr_page2))) + page = true; + } + + return page; +} + +static inline int find_error_code(unsigned int sdw_ret) +{ + switch (sdw_ret) { + case SDW_CMD_OK: + return 0; + + case SDW_CMD_IGNORED: + return -ENODATA; + + case SDW_CMD_TIMEOUT: + return -ETIMEDOUT; + } + + return -EIO; +} + +static inline int do_transfer(struct sdw_bus *bus, + struct sdw_msg *msg, bool page) +{ + int retry = bus->prop.err_threshold; + int ret, i; + + for (ret = 0, i = 0; i <= retry; i++) { + ret = bus->ops->xfer_msg(bus, msg, page); + ret = find_error_code(ret); + /* if cmd is ok or ignored return */ + if (ret == 0 || ret == -ENODATA) + return ret; + } + + return ret; +} + +static inline int do_transfer_defer(struct sdw_bus *bus, + struct sdw_msg *msg, bool page, + struct sdw_defer *defer) +{ + int retry = bus->prop.err_threshold; + int ret, i; + + defer->msg = msg; + defer->length = msg->len; + + for (ret = 0, i = 0; i <= retry; i++) { + + ret = bus->ops->xfer_msg_defer(bus, msg, page, defer); + ret = find_error_code(ret); + /* if cmd is ok or ignored return */ + if (ret == 0 || ret == -ENODATA) + return ret; + } + + return ret; +} + +static int sdw_reset_page(struct sdw_bus *bus, u16 dev_num) +{ + int retry = bus->prop.err_threshold; + int ret, i; + + for (ret = 0, i = 0; i <= retry; i++) { + ret = bus->ops->reset_page_addr(bus, dev_num); + ret = find_error_code(ret); + /* if cmd is ok or ignored return */ + if (ret == 0 || ret == -ENODATA) + return ret; + } + + return ret; +} + +/** + * sdw_transfer: Synchronous transfer message to a SDW Slave device + * + * @bus: SDW bus + * @slave: SDW Slave + * @msg: SDW message to be xfered + */ +int sdw_transfer(struct sdw_bus *bus, struct sdw_slave *slave, + struct sdw_msg *msg) +{ + bool page; + int ret; + + mutex_lock(&bus->msg_lock); + + page = sdw_get_page(slave, msg); + + ret = do_transfer(bus, msg, page); + if (ret != 0 && ret != -ENODATA) { + dev_err(bus->dev, "trf on Slave %d failed:%d\n", + msg->dev_num, ret); + goto error; + } + + if (page) + ret = sdw_reset_page(bus, msg->dev_num); + +error: + mutex_unlock(&bus->msg_lock); + + return ret; +} + +/** + * sdw_transfer_defer: Asynchronously transfer message to a SDW Slave device + * + * @bus: SDW bus + * @slave: SDW Slave + * @msg: SDW message to be xfered + * @defer: Defer block for signal completion + * + * Caller needs to hold the msg_lock lock while calling this + */ +int sdw_transfer_defer(struct sdw_bus *bus, struct sdw_slave *slave, + struct sdw_msg *msg, struct sdw_defer *defer) +{ + bool page; + int ret; + + if (!bus->ops->xfer_msg_defer) + return -ENOTSUPP; + + page = sdw_get_page(slave, msg); + + ret = do_transfer_defer(bus, msg, page, defer); + if (ret != 0 && ret != -ENODATA) + goto error; + + if (page) + ret = sdw_reset_page(bus, msg->dev_num); + +error: + return ret; +} + +static inline int sdw_fill_msg(struct sdw_msg *msg, u16 addr, + size_t count, u16 dev_num, u8 flags, u8 *buf) +{ + msg->addr = (addr >> SDW_REG_SHIFT(SDW_REGADDR)); + msg->len = count; + msg->dev_num = dev_num; + msg->addr_page1 = (addr >> SDW_REG_SHIFT(SDW_SCP_ADDRPAGE1_MASK)); + msg->addr_page2 = (addr >> SDW_REG_SHIFT(SDW_SCP_ADDRPAGE2_MASK)); + msg->flags = flags; + msg->buf = buf; + msg->ssp_sync = false; + + return 0; +} + +/** + * sdw_nread: Read "n" contiguous SDW Slave registers + * + * @slave: SDW Slave + * @addr: Register address + * @count: length + * @val: Buffer for values to be read + */ +int sdw_nread(struct sdw_slave *slave, u32 addr, size_t count, u8 *val) +{ + struct sdw_msg msg; + int ret; + + pm_runtime_get_sync(slave->bus->dev); + + sdw_fill_msg(&msg, addr, count, slave->dev_num, SDW_MSG_FLAG_READ, val); + ret = sdw_transfer(slave->bus, slave, &msg); + pm_runtime_put(slave->bus->dev); + + return ret; +} +EXPORT_SYMBOL(sdw_nread); + +/** + * sdw_nwrite: Write "n" contiguous SDW Slave registers + * + * @slave: SDW Slave + * @addr: Register address + * @count: length + * @val: Buffer for values to be read + */ +int sdw_nwrite(struct sdw_slave *slave, u32 addr, size_t count, u8 *val) +{ + struct sdw_msg msg; + int ret; + + pm_runtime_get_sync(slave->bus->dev); + + sdw_fill_msg(&msg, addr, count, slave->dev_num, SDW_MSG_FLAG_WRITE, val); + ret = sdw_transfer(slave->bus, slave, &msg); + pm_runtime_put(slave->bus->dev); + + return ret; +} +EXPORT_SYMBOL(sdw_nwrite); + +/** + * sdw_read: Read a SDW Slave register + * + * @slave: SDW Slave + * @addr: Register address + */ +int sdw_read(struct sdw_slave *slave, u32 addr) +{ + u8 buf; + int ret; + + ret = sdw_nread(slave, addr, 1, &buf); + if (ret < 0) + return ret; + else + return buf; +} +EXPORT_SYMBOL(sdw_read); + +/** + * sdw_write: Write a SDW Slave register + * + * @slave: SDW Slave + * @addr: Register address + * @value: Register value + */ +int sdw_write(struct sdw_slave *slave, u32 addr, u8 value) +{ + return sdw_nwrite(slave, addr, 1, &value); + +} +EXPORT_SYMBOL(sdw_write); + void sdw_extract_slave_id(struct sdw_bus *bus, unsigned long long addr, struct sdw_slave_id *id) { diff --git a/drivers/soundwire/bus.h b/drivers/soundwire/bus.h index f61bc9f59445..bd3b7d230076 100644 --- a/drivers/soundwire/bus.h +++ b/drivers/soundwire/bus.h @@ -79,4 +79,37 @@ int sdw_slave_modalias(struct sdw_slave *slave, char *buf, size_t size); void sdw_extract_slave_id(struct sdw_bus *bus, unsigned long long addr, struct sdw_slave_id *id); +enum { + SDW_MSG_FLAG_READ = 0, + SDW_MSG_FLAG_WRITE, +}; + +/** + * struct sdw_msg: Message structure + * + * @addr: Register address accessed in the Slave + * @len: number of messages + * @dev_num: Slave device number + * @addr_page1: SCP address page 1 Slave register + * @addr_page2: SCP address page 2 Slave register + * @flags: transfer flags, indicate if xfer is read or write + * @buf: message data buffer + * @ssp_sync: Send message at SSP (Stream Synchronization Point) + */ +struct sdw_msg { + u16 addr; + u16 len; + u16 dev_num; + u8 addr_page1; + u8 addr_page2; + u8 flags; + u8 *buf; + bool ssp_sync; +}; + +int sdw_transfer(struct sdw_bus *bus, struct sdw_slave *slave, + struct sdw_msg *msg); +int sdw_transfer_defer(struct sdw_bus *bus, struct sdw_slave *slave, + struct sdw_msg *msg, struct sdw_defer *defer); + #endif /* __SDW_BUS_H */ diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h index a5bb5e9bc50a..af94c0a29024 100644 --- a/include/linux/soundwire/sdw.h +++ b/include/linux/soundwire/sdw.h @@ -57,6 +57,14 @@ struct sdw_bus; struct sdw_slave; +/* SDW spec defines and enums, as defined by MIPI 1.1. Spec */ + +/* SDW Broadcast addr */ +#define SDW_BROADCAST_DEV_NUM 15 + +/* SDW Enumeration Device Number */ +#define SDW_ENUM_DEV_NUM 0 + #define SDW_MAX_DEVICES 11 /** @@ -74,6 +82,28 @@ enum sdw_slave_status { SDW_SLAVE_RESERVED = 3, }; +/** + * enum sdw_command_response: Command response as defined by SDW spec + * + * @SDW_CMD_OK: cmd was successful + * @SDW_CMD_IGNORED: cmd was ignored + * @SDW_CMD_FAIL: cmd was NACKed + * @SDW_CMD_TIMEOUT: cmd timedout + * @SDW_CMD_FAIL_OTHER: cmd failed due to other reason than above + * + * NOTE: The enum is different than actual Spec as response in the Spec is + * combination of ACK/NAK bits + * + * SDW_CMD_TIMEOUT/FAIL_OTHER is defined for SW use, not in spec + */ +enum sdw_command_response { + SDW_CMD_OK = 0, + SDW_CMD_IGNORED = 1, + SDW_CMD_FAIL = 2, + SDW_CMD_TIMEOUT = 4, + SDW_CMD_FAIL_OTHER = 8, +}; + /* * SDW properties, defined in MIPI DisCo spec v1.0 */ @@ -422,13 +452,39 @@ void sdw_unregister_driver(struct sdw_driver *drv); * SDW master structures and APIs */ +struct sdw_msg; + +/** + * struct sdw_defer: SDW deffered message + * + * @length: message length + * @complete: message completion + * @msg: SDW message + */ +struct sdw_defer { + int length; + struct completion complete; + struct sdw_msg *msg; +}; + /** * struct sdw_master_ops: Master driver ops * * @read_prop: Read Master properties + * @xfer_msg: Transfer message callback + * @xfer_msg_defer: Defer version of transfer message callback + * @reset_page_addr: Reset the SCP page address registers */ struct sdw_master_ops { int (*read_prop)(struct sdw_bus *bus); + + enum sdw_command_response (*xfer_msg) + (struct sdw_bus *bus, struct sdw_msg *msg, int page); + enum sdw_command_response (*xfer_msg_defer) + (struct sdw_bus *bus, struct sdw_msg *msg, + int page, struct sdw_defer *defer); + enum sdw_command_response (*reset_page_addr) + (struct sdw_bus *bus, unsigned int dev_num); }; /** @@ -439,8 +495,10 @@ struct sdw_master_ops { * @slaves: list of Slaves on this bus * @assigned: logical addresses assigned, Index 0 (broadcast) would be unused * @bus_lock: bus lock + * @msg_lock: message lock * @ops: Master callback ops * @prop: Master properties + * @defer_msg: Defer message * @clk_stop_timeout: Clock stop timeout computed */ struct sdw_bus { @@ -449,12 +507,21 @@ struct sdw_bus { struct list_head slaves; bool assigned[SDW_MAX_DEVICES + 1]; struct mutex bus_lock; + struct mutex msg_lock; const struct sdw_master_ops *ops; struct sdw_master_prop prop; + struct sdw_defer defer_msg; unsigned int clk_stop_timeout; }; int sdw_add_bus_master(struct sdw_bus *bus); void sdw_delete_bus_master(struct sdw_bus *bus); +/* messaging and data APIs */ + +int sdw_read(struct sdw_slave *slave, u32 addr); +int sdw_write(struct sdw_slave *slave, u32 addr, u8 value); +int sdw_nread(struct sdw_slave *slave, u32 addr, size_t count, u8 *val); +int sdw_nwrite(struct sdw_slave *slave, u32 addr, size_t count, u8 *val); + #endif /* __SOUNDWIRE_H */

[06/14] soundwire: Add IO transfer

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