[PATCH v5 8/8] drivers/fsi: occ: Add in-kernel API
From: Eddie James
Date: Mon Nov 20 2017 - 14:48:05 EST
From: "Edward A. James" <eajames@xxxxxxxxxx>
Add an in-kernel read/write API with exported functions. This is
necessary for other drivers which want to directly interact with the
OCC. Also add a child platform device node for the associated hwmon
device.
Signed-off-by: Edward A. James <eajames@xxxxxxxxxx>
---
drivers/fsi/fsi-occ.c | 138 ++++++++++++++++++++++++++++++++++++++++--------
include/linux/fsi-occ.h | 41 ++++++++++++++
2 files changed, 157 insertions(+), 22 deletions(-)
create mode 100644 include/linux/fsi-occ.h
diff --git a/drivers/fsi/fsi-occ.c b/drivers/fsi/fsi-occ.c
index 1aeb67d..1713550 100644
--- a/drivers/fsi/fsi-occ.c
+++ b/drivers/fsi/fsi-occ.c
@@ -19,7 +19,9 @@
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/mutex.h>
+#include <linux/fsi-occ.h>
#include <linux/of.h>
+#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/sched.h>
#include <linux/slab.h>
@@ -32,8 +34,6 @@
#define OCC_CMD_DATA_BYTES 4090
#define OCC_RESP_DATA_BYTES 4089
-#define OCC_RESP_CMD_IN_PRG 0xFF
-
#define OCC_TIMEOUT_MS 1000
#define OCC_CMD_IN_PRG_WAIT_MS 50
@@ -156,23 +156,34 @@ static void occ_put_client(struct occ_client *client)
kref_put(&client->kref, occ_client_release);
}
-static int occ_open(struct inode *inode, struct file *file)
+static struct occ_client *occ_open_common(struct occ *occ, unsigned long flags)
{
- struct miscdevice *mdev = file->private_data;
- struct occ *occ = to_occ(mdev);
struct occ_client *client = kzalloc(sizeof(*client), GFP_KERNEL);
if (!client)
- return -ENOMEM;
+ return NULL;
client->occ = occ;
kref_init(&client->kref);
spin_lock_init(&client->lock);
init_waitqueue_head(&client->wait);
- if (file->f_flags & O_NONBLOCK)
+ if (flags & O_NONBLOCK)
set_bit(CLIENT_NONBLOCKING, &client->flags);
+ return client;
+}
+
+static int occ_open(struct inode *inode, struct file *file)
+{
+ struct occ_client *client;
+ struct miscdevice *mdev = file->private_data;
+ struct occ *occ = to_occ(mdev);
+
+ client = occ_open_common(occ, file->f_flags);
+ if (!client)
+ return -ENOMEM;
+
file->private_data = client;
return 0;
@@ -184,15 +195,14 @@ static inline bool occ_read_ready(struct occ_xfr *xfr, struct occ *occ)
test_bit(XFR_CANCELED, &xfr->flags) || occ->cancel;
}
-static ssize_t occ_read(struct file *file, char __user *buf, size_t len,
- loff_t *offset)
+static ssize_t occ_read_common(struct occ_client *client, char __user *ubuf,
+ char *kbuf, size_t len)
{
int rc;
unsigned long flags;
size_t bytes;
struct occ_xfr *xfr;
struct occ *occ;
- struct occ_client *client = file->private_data;
if (!client)
return -ENODEV;
@@ -247,9 +257,14 @@ static ssize_t occ_read(struct file *file, char __user *buf, size_t len,
}
bytes = min(len, xfr->resp_data_length - client->read_offset);
- if (copy_to_user(buf, &xfr->buf[client->read_offset], bytes)) {
- rc = -EFAULT;
- goto done;
+ if (ubuf) {
+ if (copy_to_user(ubuf, &xfr->buf[client->read_offset],
+ bytes)) {
+ rc = -EFAULT;
+ goto done;
+ }
+ } else {
+ memcpy(kbuf, &xfr->buf[client->read_offset], bytes);
}
client->read_offset += bytes;
@@ -266,15 +281,23 @@ static ssize_t occ_read(struct file *file, char __user *buf, size_t len,
return rc;
}
-static ssize_t occ_write(struct file *file, const char __user *buf,
- size_t len, loff_t *offset)
+static ssize_t occ_read(struct file *file, char __user *buf, size_t len,
+ loff_t *offset)
+{
+ struct occ_client *client = file->private_data;
+
+ return occ_read_common(client, buf, NULL, len);
+}
+
+static ssize_t occ_write_common(struct occ_client *client,
+ const char __user *ubuf, const char *kbuf,
+ size_t len)
{
int rc;
unsigned long flags;
unsigned int i;
u16 data_length, checksum = 0;
struct occ_xfr *xfr;
- struct occ_client *client = file->private_data;
if (!client)
return -ENODEV;
@@ -301,9 +324,13 @@ static ssize_t occ_write(struct file *file, const char __user *buf,
* bytes 1-2: data length (msb first)
* bytes 3-n: data
*/
- if (copy_from_user(&xfr->buf[1], buf, len)) {
- rc = -EFAULT;
- goto done;
+ if (ubuf) {
+ if (copy_from_user(&xfr->buf[1], ubuf, len)) {
+ rc = -EFAULT;
+ goto done;
+ }
+ } else {
+ memcpy(&xfr->buf[1], kbuf, len);
}
data_length = (xfr->buf[2] << 8) + xfr->buf[3];
@@ -334,12 +361,19 @@ static ssize_t occ_write(struct file *file, const char __user *buf,
return rc;
}
-static int occ_release(struct inode *inode, struct file *file)
+static ssize_t occ_write(struct file *file, const char __user *buf,
+ size_t len, loff_t *offset)
+{
+ struct occ_client *client = file->private_data;
+
+ return occ_write_common(client, buf, NULL, len);
+}
+
+static int occ_release_common(struct occ_client *client)
{
unsigned long flags;
struct occ *occ;
struct occ_xfr *xfr;
- struct occ_client *client = file->private_data;
if (!client)
return -ENODEV;
@@ -372,6 +406,13 @@ static int occ_release(struct inode *inode, struct file *file)
return 0;
}
+static int occ_release(struct inode *inode, struct file *file)
+{
+ struct occ_client *client = file->private_data;
+
+ return occ_release_common(client);
+}
+
static const struct file_operations occ_fops = {
.owner = THIS_MODULE,
.open = occ_open,
@@ -665,12 +706,55 @@ static void occ_worker(struct work_struct *work)
goto again;
}
+struct occ_client *occ_drv_open(struct device *dev, unsigned long flags)
+{
+ struct occ *occ = dev_get_drvdata(dev);
+
+ if (!occ)
+ return NULL;
+
+ return occ_open_common(occ, flags);
+}
+EXPORT_SYMBOL_GPL(occ_drv_open);
+
+int occ_drv_read(struct occ_client *client, char *buf, size_t len)
+{
+ return occ_read_common(client, NULL, buf, len);
+}
+EXPORT_SYMBOL_GPL(occ_drv_read);
+
+int occ_drv_write(struct occ_client *client, const char *buf, size_t len)
+{
+ return occ_write_common(client, NULL, buf, len);
+}
+EXPORT_SYMBOL_GPL(occ_drv_write);
+
+void occ_drv_release(struct occ_client *client)
+{
+ occ_release_common(client);
+}
+EXPORT_SYMBOL_GPL(occ_drv_release);
+
+static int occ_unregister_child(struct device *dev, void *data)
+{
+ struct platform_device *child = to_platform_device(dev);
+
+ of_device_unregister(child);
+ if (dev->of_node)
+ of_node_clear_flag(dev->of_node, OF_POPULATED);
+
+ return 0;
+}
+
static int occ_probe(struct platform_device *pdev)
{
- int rc;
+ int rc, child_idx = 0;
u32 reg;
struct occ *occ;
+ struct device_node *np;
+ struct platform_device *child;
struct device *dev = &pdev->dev;
+ char child_name[32];
occ = devm_kzalloc(dev, sizeof(*occ), GFP_KERNEL);
if (!occ)
@@ -712,6 +796,15 @@ static int occ_probe(struct platform_device *pdev)
return rc;
}
+ /* create platform devs for dts child nodes (hwmon, etc) */
+ for_each_available_child_of_node(dev->of_node, np) {
+ snprintf(child_name, sizeof(child_name), "occ%d-dev%d",
+ occ->idx, child_idx++);
+ child = of_platform_device_create(np, child_name, dev);
+ if (!child)
+ dev_warn(dev, "failed to create child node dev\n");
+ }
+
platform_set_drvdata(pdev, occ);
return 0;
@@ -734,6 +827,7 @@ static int occ_remove(struct platform_device *pdev)
spin_unlock_irqrestore(&occ->list_lock, flags);
misc_deregister(&occ->mdev);
+ device_for_each_child(&pdev->dev, NULL, occ_unregister_child);
cancel_work_sync(&occ->work);
diff --git a/include/linux/fsi-occ.h b/include/linux/fsi-occ.h
new file mode 100644
index 0000000..0a4a54a
--- /dev/null
+++ b/include/linux/fsi-occ.h
@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) IBM Corporation 2017
+ *
+ * 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
+ * MERGCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef LINUX_FSI_OCC_H
+#define LINUX_FSI_OCC_H
+
+struct device;
+struct occ_client;
+
+#define OCC_RESP_CMD_IN_PRG 0xFF
+#define OCC_RESP_SUCCESS 0
+#define OCC_RESP_CMD_INVAL 0x11
+#define OCC_RESP_CMD_LEN_INVAL 0x12
+#define OCC_RESP_DATA_INVAL 0x13
+#define OCC_RESP_CHKSUM_ERR 0x14
+#define OCC_RESP_INT_ERR 0x15
+#define OCC_RESP_BAD_STATE 0x16
+#define OCC_RESP_CRIT_EXCEPT 0xE0
+#define OCC_RESP_CRIT_INIT 0xE1
+#define OCC_RESP_CRIT_WATCHDOG 0xE2
+#define OCC_RESP_CRIT_OCB 0xE3
+#define OCC_RESP_CRIT_HW 0xE4
+
+extern struct occ_client *occ_drv_open(struct device *dev,
+ unsigned long flags);
+extern int occ_drv_read(struct occ_client *client, char *buf, size_t len);
+extern int occ_drv_write(struct occ_client *client, const char *buf,
+ size_t len);
+extern void occ_drv_release(struct occ_client *client);
+
+#endif /* LINUX_FSI_OCC_H */
--
1.8.3.1