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authorJeremy Kerr <jk@ozlabs.org>2017-06-06 16:08:42 -0500
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-06-09 11:52:08 +0200
commit2b545cd8e1b2a2bd60d991c7f1b45a30c673ece2 (patch)
tree3d9c79a85314da5fe75a62046ee280c1139002a9 /drivers/fsi/fsi-core.c
parent26095282119ecf1088193d09388fa40700e34e45 (diff)
drivers/fsi: Implement slave initialisation
Implement fsi_slave_init: if we can read a chip ID, create fsi_slave devices and register with the driver core. Includes changes from Christopher Bostic <cbostic@linux.vnet.ibm.com>. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/fsi/fsi-core.c')
-rw-r--r--drivers/fsi/fsi-core.c67
1 files changed, 65 insertions, 2 deletions
diff --git a/drivers/fsi/fsi-core.c b/drivers/fsi/fsi-core.c
index 235f17a6d89e..9d9adc17072c 100644
--- a/drivers/fsi/fsi-core.c
+++ b/drivers/fsi/fsi-core.c
@@ -13,13 +13,17 @@
* GNU General Public License for more details.
*/
+#include <linux/crc4.h>
#include <linux/device.h>
#include <linux/fsi.h>
#include <linux/idr.h>
#include <linux/module.h>
+#include <linux/slab.h>
#include "fsi-master.h"
+#define FSI_SLAVE_SIZE_23b 0x800000
+
static DEFINE_IDA(master_ida);
struct fsi_slave {
@@ -90,11 +94,70 @@ static int fsi_slave_write(struct fsi_slave *slave, uint32_t addr,
addr, val, size);
}
+static void fsi_slave_release(struct device *dev)
+{
+ struct fsi_slave *slave = to_fsi_slave(dev);
+
+ kfree(slave);
+}
+
static int fsi_slave_init(struct fsi_master *master, int link, uint8_t id)
{
- /* todo: initialise slave device, perform engine scan */
+ struct fsi_slave *slave;
+ uint32_t chip_id;
+ uint8_t crc;
+ int rc;
+
+ /* Currently, we only support single slaves on a link, and use the
+ * full 23-bit address range
+ */
+ if (id != 0)
+ return -EINVAL;
+
+ rc = fsi_master_read(master, link, id, 0, &chip_id, sizeof(chip_id));
+ if (rc) {
+ dev_dbg(&master->dev, "can't read slave %02x:%02x %d\n",
+ link, id, rc);
+ return -ENODEV;
+ }
+ chip_id = be32_to_cpu(chip_id);
+
+ crc = crc4(0, chip_id, 32);
+ if (crc) {
+ dev_warn(&master->dev, "slave %02x:%02x invalid chip id CRC!\n",
+ link, id);
+ return -EIO;
+ }
+
+ dev_info(&master->dev, "fsi: found chip %08x at %02x:%02x:%02x\n",
+ chip_id, master->idx, link, id);
+
+ /* We can communicate with a slave; create the slave device and
+ * register.
+ */
+ slave = kzalloc(sizeof(*slave), GFP_KERNEL);
+ if (!slave)
+ return -ENOMEM;
+
+ slave->master = master;
+ slave->dev.parent = &master->dev;
+ slave->dev.release = fsi_slave_release;
+ slave->link = link;
+ slave->id = id;
+ slave->size = FSI_SLAVE_SIZE_23b;
+
+ dev_set_name(&slave->dev, "slave@%02x:%02x", link, id);
+ rc = device_register(&slave->dev);
+ if (rc < 0) {
+ dev_warn(&master->dev, "failed to create slave device: %d\n",
+ rc);
+ put_device(&slave->dev);
+ return rc;
+ }
+
+ /* todo: perform engine scan */
- return -ENODEV;
+ return rc;
}
/* FSI master support */

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