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path: root/drivers/soundwire/bus.c
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Diffstat (limited to 'drivers/soundwire/bus.c')
-rw-r--r--drivers/soundwire/bus.c272
1 files changed, 272 insertions, 0 deletions
diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c
index 9626bd1ab271..fb9008d6c40e 100644
--- a/drivers/soundwire/bus.c
+++ b/drivers/soundwire/bus.c
@@ -3,6 +3,8 @@
#include <linux/acpi.h>
#include <linux/mod_devicetable.h>
+#include <linux/pm_runtime.h>
+#include <linux/soundwire/sdw_registers.h>
#include <linux/soundwire/sdw.h>
#include "bus.h"
@@ -22,6 +24,12 @@ 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);
@@ -102,6 +110,270 @@ void sdw_delete_bus_master(struct sdw_bus *bus)
}
EXPORT_SYMBOL(sdw_delete_bus_master);
+/*
+ * SDW IO Calls
+ */
+
+static inline int find_response_code(enum sdw_command_response resp)
+{
+ switch (resp) {
+ case SDW_CMD_OK:
+ return 0;
+
+ case SDW_CMD_IGNORED:
+ return -ENODATA;
+
+ case SDW_CMD_TIMEOUT:
+ return -ETIMEDOUT;
+
+ default:
+ return -EIO;
+ }
+}
+
+static inline int do_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
+{
+ int retry = bus->prop.err_threshold;
+ enum sdw_command_response resp;
+ int ret = 0, i;
+
+ for (i = 0; i <= retry; i++) {
+ resp = bus->ops->xfer_msg(bus, msg);
+ ret = find_response_code(resp);
+
+ /* 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, struct sdw_defer *defer)
+{
+ int retry = bus->prop.err_threshold;
+ enum sdw_command_response resp;
+ int ret = 0, i;
+
+ defer->msg = msg;
+ defer->length = msg->len;
+
+ for (i = 0; i <= retry; i++) {
+ resp = bus->ops->xfer_msg_defer(bus, msg, defer);
+ ret = find_response_code(resp);
+ /* 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;
+ enum sdw_command_response resp;
+ int ret = 0, i;
+
+ for (i = 0; i <= retry; i++) {
+ resp = bus->ops->reset_page_addr(bus, dev_num);
+ ret = find_response_code(resp);
+ /* 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
+ * @msg: SDW message to be xfered
+ */
+int sdw_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
+{
+ int ret;
+
+ mutex_lock(&bus->msg_lock);
+
+ ret = do_transfer(bus, msg);
+ if (ret != 0 && ret != -ENODATA)
+ dev_err(bus->dev, "trf on Slave %d failed:%d\n",
+ msg->dev_num, ret);
+
+ if (msg->page)
+ sdw_reset_page(bus, msg->dev_num);
+
+ mutex_unlock(&bus->msg_lock);
+
+ return ret;
+}
+
+/**
+ * sdw_transfer_defer() - Asynchronously transfer message to a SDW Slave device
+ * @bus: SDW bus
+ * @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_msg *msg,
+ struct sdw_defer *defer)
+{
+ int ret;
+
+ if (!bus->ops->xfer_msg_defer)
+ return -ENOTSUPP;
+
+ ret = do_transfer_defer(bus, msg, defer);
+ if (ret != 0 && ret != -ENODATA)
+ dev_err(bus->dev, "Defer trf on Slave %d failed:%d\n",
+ msg->dev_num, ret);
+
+ if (msg->page)
+ sdw_reset_page(bus, msg->dev_num);
+
+ return ret;
+}
+
+
+int sdw_fill_msg(struct sdw_msg *msg, struct sdw_slave *slave,
+ u32 addr, size_t count, u16 dev_num, u8 flags, u8 *buf)
+{
+ memset(msg, 0, sizeof(*msg));
+ msg->addr = addr; /* addr is 16 bit and truncated here */
+ msg->len = count;
+ msg->dev_num = dev_num;
+ msg->flags = flags;
+ msg->buf = buf;
+ msg->ssp_sync = false;
+ msg->page = false;
+
+ if (addr < SDW_REG_NO_PAGE) { /* no paging area */
+ return 0;
+ } else if (addr >= SDW_REG_MAX) { /* illegal addr */
+ pr_err("SDW: Invalid address %x passed\n", addr);
+ return -EINVAL;
+ }
+
+ if (addr < SDW_REG_OPTIONAL_PAGE) { /* 32k but no page */
+ if (slave && !slave->prop.paging_support)
+ return 0;
+ /* no need for else as that will fall thru to paging */
+ }
+
+ /* paging mandatory */
+ if (dev_num == SDW_ENUM_DEV_NUM || dev_num == SDW_BROADCAST_DEV_NUM) {
+ pr_err("SDW: Invalid device for paging :%d\n", dev_num);
+ return -EINVAL;
+ }
+
+ if (!slave) {
+ pr_err("SDW: No slave for paging addr\n");
+ return -EINVAL;
+ } else if (!slave->prop.paging_support) {
+ dev_err(&slave->dev,
+ "address %x needs paging but no support", addr);
+ return -EINVAL;
+ }
+
+ msg->addr_page1 = (addr >> SDW_REG_SHIFT(SDW_SCP_ADDRPAGE1_MASK));
+ msg->addr_page2 = (addr >> SDW_REG_SHIFT(SDW_SCP_ADDRPAGE2_MASK));
+ msg->addr |= BIT(15);
+ msg->page = true;
+
+ 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;
+
+ ret = sdw_fill_msg(&msg, slave, addr, count,
+ slave->dev_num, SDW_MSG_FLAG_READ, val);
+ if (ret < 0)
+ return ret;
+
+ ret = pm_runtime_get_sync(slave->bus->dev);
+ if (!ret)
+ return ret;
+
+ ret = sdw_transfer(slave->bus, &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;
+
+ ret = sdw_fill_msg(&msg, slave, addr, count,
+ slave->dev_num, SDW_MSG_FLAG_WRITE, val);
+ if (ret < 0)
+ return ret;
+
+ ret = pm_runtime_get_sync(slave->bus->dev);
+ if (!ret)
+ return ret;
+
+ ret = sdw_transfer(slave->bus, &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,
u64 addr, struct sdw_slave_id *id)
{
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-22 22:34:40 +0000