From: Jeremy Kerr <j...@ozlabs.org>

For debugging, add a fake master driver, that only supports reads,
returning a fixed set of data.

Includes changes from Chris Bostic <cbos...@us.ibm.com>.

Signed-off-by: Jeremy Kerr <j...@ozlabs.org>
Signed-off-by: Chris Bostic <cbos...@us.ibm.com>
---
 drivers/fsi/Kconfig           | 10 +++++
 drivers/fsi/Makefile          |  1 +
 drivers/fsi/fsi-master-fake.c | 95 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 106 insertions(+)
 create mode 100644 drivers/fsi/fsi-master-fake.c

diff --git a/drivers/fsi/Kconfig b/drivers/fsi/Kconfig
index 04c1a0e..f065dbe 100644
--- a/drivers/fsi/Kconfig
+++ b/drivers/fsi/Kconfig
@@ -9,4 +9,14 @@ config FSI
        ---help---
          FSI - the FRU Support Interface - is a simple bus for low-level
          access to POWER-based hardware.
+
+if FSI
+
+config FSI_MASTER_FAKE
+       tristate "Fake FSI master"
+       depends on FSI
+       ---help---
+       This option enables a fake FSI master driver for debugging.
+endif
+
 endmenu
diff --git a/drivers/fsi/Makefile b/drivers/fsi/Makefile
index db0e5e7..847c00c 100644
--- a/drivers/fsi/Makefile
+++ b/drivers/fsi/Makefile
@@ -1,2 +1,3 @@
 
 obj-$(CONFIG_FSI) += fsi-core.o
+obj-$(CONFIG_FSI_MASTER_FAKE) += fsi-master-fake.o
diff --git a/drivers/fsi/fsi-master-fake.c b/drivers/fsi/fsi-master-fake.c
new file mode 100644
index 0000000..b42fe5b
--- /dev/null
+++ b/drivers/fsi/fsi-master-fake.c
@@ -0,0 +1,95 @@
+/*
+ * Fake FSI master driver for FSI development
+ *
+ * Copyright (C) IBM Corporation 2016
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License 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/platform_device.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+
+#include "fsi-master.h"
+
+static const uint8_t data[] = {
+       0xc0, 0x02, 0x08, 0x03, /* chip id */
+       0x80, 0x01, 0x11, 0x00, /* peek */
+       0x80, 0x01, 0x20, 0x3e, /* slave */
+       0x00, 0x01, 0x10, 0xa5, /* i2c */
+};
+
+
+static int fsi_master_fake_read(struct fsi_master *_master, int link,
+               uint8_t slave, uint32_t addr, void *val, size_t size)
+{
+       if (link != 0)
+               return -ENODEV;
+
+       if (addr + size > sizeof(data))
+               memset(val, 0, size);
+       else
+               memcpy(val, data + addr, size);
+
+       return 0;
+}
+
+static int fsi_master_fake_write(struct fsi_master *_master, int link,
+               uint8_t slave, uint32_t addr, const void *val, size_t size)
+{
+       if (link != 0)
+               return -ENODEV;
+
+       return -EACCES;
+}
+
+static int fsi_master_fake_probe(struct platform_device *pdev)
+{
+       struct fsi_master *master;
+
+       master = devm_kzalloc(&pdev->dev, sizeof(*master), GFP_KERNEL);
+       if (!master)
+               return -ENOMEM;
+
+       master->dev = &pdev->dev;
+       master->n_links = 1;
+       master->read = fsi_master_fake_read;
+       master->write = fsi_master_fake_write;
+
+       return fsi_master_register(master);
+}
+
+static const struct of_device_id fsi_master_fake_match[] = {
+       { .compatible = "ibm,fsi-master-fake" },
+       { },
+};
+
+static struct platform_driver fsi_master_fake_driver = {
+       .driver = {
+               .name           = "fsi-master-fake",
+               .of_match_table = fsi_master_fake_match,
+       },
+       .probe  = fsi_master_fake_probe,
+};
+
+static int __init fsi_master_fake_init(void)
+{
+       struct device_node *np;
+
+       platform_driver_register(&fsi_master_fake_driver);
+
+       for_each_compatible_node(np, NULL, "ibm,fsi-master-fake")
+               of_platform_device_create(np, NULL, NULL);
+
+       return 0;
+}
+
+module_init(fsi_master_fake_init);
-- 
1.8.2.2

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