From: Jeremy Kerr <jk@xxxxxxxxxx>
This change introduces the fsi device API: simple read, write and peek
accessors for the devices' address spaces.
Includes contributions from Christopher Bostic
<cbostic@xxxxxxxxxxxxxxxxxx> and Edward A. James <eajames@xxxxxxxxxx>.
Signed-off-by: Edward A. James <eajames@xxxxxxxxxx>
Signed-off-by: Jeremy Kerr <jk@xxxxxxxxxx>
Signed-off-by: Christopher Bostic <cbostic@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Joel Stanley <joel@xxxxxxxxx>
---
v7 - Add API details for fsi_device_read/write/peek().
---
drivers/fsi/fsi-core.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++++-
include/linux/fsi.h | 7 ++++++-
2 files changed, 55 insertions(+), 2 deletions(-)
diff --git a/drivers/fsi/fsi-core.c b/drivers/fsi/fsi-core.c
index eac0bc4..d7a6e76 100644
--- a/drivers/fsi/fsi-core.c
+++ b/drivers/fsi/fsi-core.c
@@ -34,6 +34,8 @@
#define FSI_SLAVE_CONF_CRC_MASK GENMASK(3, 0)
#define FSI_SLAVE_CONF_DATA_BITS 28
+#define FSI_PEEK_BASE 0x410
+
static const int engine_page_size = 0x400;
#define FSI_SLAVE_BASE 0x800
@@ -75,8 +77,54 @@ static int fsi_master_read(struct fsi_master *master, int link,
uint8_t slave_id, uint32_t addr, void *val, size_t size);
static int fsi_master_write(struct fsi_master *master, int link,
uint8_t slave_id, uint32_t addr, const void *val, size_t size);
+static int fsi_slave_read(struct fsi_slave *slave, uint32_t addr,
+ void *val, size_t size);
+static int fsi_slave_write(struct fsi_slave *slave, uint32_t addr,
+ const void *val, size_t size);
+
+/*
+ * fsi_device_read() / fsi_device_write() / fsi_device_peek()
+ *
+ * FSI endpoint-device support
+ *
+ * Read / write / peek accessors for a client
+ *
+ * Parameters:
+ * dev: Structure passed to FSI client device drivers on probe().
+ * addr: FSI address of given device. Client should pass in its base address
+ * plus desired offset to access its register space.
+ * val: For read/peek this is the value read at the specified address. For
+ * write this is value to write to the specified address.
+ * The data in val must be FSI bus endian (big endian).
+ * size: Size in bytes of the operation. Sizes supported are 1, 2 and 4 bytes.
+ * Addresses must be aligned on size boundaries or an error will result.
+ */
+int fsi_device_read(struct fsi_device *dev, uint32_t addr, void *val,
+ size_t size)
+{
+ if (addr > dev->size || size > dev->size || addr > dev->size - size)
+ return -EINVAL;
-/* FSI endpoint-device support */
+ return fsi_slave_read(dev->slave, dev->addr + addr, val, size);
+}
+EXPORT_SYMBOL_GPL(fsi_device_read);
+
+int fsi_device_write(struct fsi_device *dev, uint32_t addr, const void *val,
+ size_t size)
+{
+ if (addr > dev->size || size > dev->size || addr > dev->size - size)
+ return -EINVAL;
+
+ return fsi_slave_write(dev->slave, dev->addr + addr, val, size);
+}
+EXPORT_SYMBOL_GPL(fsi_device_write);
+
+int fsi_device_peek(struct fsi_device *dev, void *val)
+{
+ uint32_t addr = FSI_PEEK_BASE + ((dev->unit - 2) * sizeof(uint32_t));
+
+ return fsi_slave_read(dev->slave, addr, val, sizeof(uint32_t));
+}
static void fsi_device_release(struct device *_device)
{
diff --git a/include/linux/fsi.h b/include/linux/fsi.h
index efa55ba..66bce48 100644
--- a/include/linux/fsi.h
+++ b/include/linux/fsi.h
@@ -27,6 +27,12 @@ struct fsi_device {
uint32_t size;
};
+extern int fsi_device_read(struct fsi_device *dev, uint32_t addr,
+ void *val, size_t size);
+extern int fsi_device_write(struct fsi_device *dev, uint32_t addr,
+ const void *val, size_t size);
+extern int fsi_device_peek(struct fsi_device *dev, void *val);
+
struct fsi_device_id {
u8 engine_type;
u8 version;
@@ -40,7 +46,6 @@ struct fsi_device_id {
#define FSI_DEVICE_VERSIONED(t, v) \
.engine_type = (t), .version = (v),
-
struct fsi_driver {
struct device_driver drv;
const struct fsi_device_id *id_table;
--
1.8.2.2
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
