[PATCH 05/12] pm80xx : Support for char device.

[Deepak Ukey <deepak.ukey@microchip.com>]

From: Deepak Ukey <Deepak.Ukey@microchip.com>

Added the support to register char device for pm80xx module and
also added the ioctl functionality to get driver info.

Signed-off-by: Deepak Ukey <deepak.ukey@microchip.com>
Signed-off-by: Viswas G <Viswas.G@microchip.com>
Signed-off-by: Vishakha Channapattan <vishakhavc@google.com>
Signed-off-by: Bhavesh Jashnani <bjashnani@google.com>
Signed-off-by: Radha Ramachandran <radha@google.com>
Signed-off-by: Akshat Jain <akshatzen@google.com>
Signed-off-by: Yu Zheng <yuuzheng@google.com>
---
 drivers/scsi/pm8001/pm8001_ctl.c  | 148 ++++++++++++++++++++++++++++++++++++++
 drivers/scsi/pm8001/pm8001_ctl.h  |  33 +++++++++
 drivers/scsi/pm8001/pm8001_init.c |   5 ++
 drivers/scsi/pm8001/pm8001_sas.h  |   6 ++
 4 files changed, 192 insertions(+)

diff --git a/drivers/scsi/pm8001/pm8001_ctl.c b/drivers/scsi/pm8001/pm8001_ctl.c
index 7c6be2ec110d..69458b318a20 100644
--- a/drivers/scsi/pm8001/pm8001_ctl.c
+++ b/drivers/scsi/pm8001/pm8001_ctl.c
@@ -41,6 +41,7 @@
 #include <linux/slab.h>
 #include "pm8001_sas.h"
 #include "pm8001_ctl.h"
+int pm80xx_major = -1;
 
 /* scsi host attributes */
 
@@ -845,3 +846,150 @@ struct device_attribute *pm8001_host_attrs[] = {
 	NULL,
 };
 
+/*
+ * pm8001_open - open the configuration file
+ * @inode: inode being opened
+ * @file: file handle attached
+ *
+ * Called when the configuration device is opened. Does the needed
+ * set up on the handle and then returns
+ *
+ */
+static int pm8001_open(struct inode *inode, struct file *file)
+{
+	struct pm8001_hba_info *pm8001_ha;
+	unsigned int minor_number = iminor(inode);
+	int err = -ENODEV;
+
+	list_for_each_entry(pm8001_ha, &hba_list, list) {
+		if (pm8001_ha->id == minor_number) {
+			file->private_data = pm8001_ha;
+			err = 0;
+			break;
+		}
+	}
+
+	return err;
+}
+
+/**
+ * pm8001_close - close the configuration file
+ * @inode: inode being opened
+ * @file: file handle attached
+ *
+ * Called when the configuration device is closed. Does the needed
+ * set up on the handle and then returns
+ *
+ */
+static int pm8001_close(struct inode *inode, struct file *file)
+{
+	return 0;
+}
+
+static long pm8001_info_ioctl(struct pm8001_hba_info *pm8001_ha,
+					unsigned long arg)
+{
+	u32 ret = 0;
+	struct ioctl_info_buffer info_buf;
+
+	strcpy(info_buf.information.sz_name, DRV_NAME);
+
+	info_buf.information.usmajor_revision = DRV_MAJOR;
+	info_buf.information.usminor_revision = DRV_MINOR;
+	info_buf.information.usbuild_revision = DRV_BUILD;
+	if (pm8001_ha->chip_id == chip_8001) {
+		info_buf.information.maxoutstandingIO =
+			pm8001_ha->main_cfg_tbl.pm8001_tbl.max_out_io;
+		info_buf.information.maxdevices =
+			(pm8001_ha->main_cfg_tbl.pm8001_tbl.max_sgl >> 16) &
+			0xFFFF;
+	} else {
+		info_buf.information.maxoutstandingIO =
+			pm8001_ha->main_cfg_tbl.pm80xx_tbl.max_out_io;
+		info_buf.information.maxdevices =
+			(pm8001_ha->main_cfg_tbl.pm80xx_tbl.max_sgl >> 16) &
+			0xFFFF;
+	}
+	info_buf.header.return_code = ADPT_IOCTL_CALL_SUCCESS;
+
+	if (copy_to_user((void *)arg, (void *)&info_buf,
+				sizeof(struct ioctl_info_buffer))) {
+		ret = ADPT_IOCTL_CALL_FAILED;
+	}
+	return ret;
+}
+
+/**
+ *	pm8001_ioctl - pm8001 configuration request
+ *	@inode: inode of device
+ *	@file: file handle
+ *	@cmd: ioctl command code
+ *	@arg: argument
+ *
+ *	Handles a configuration ioctl.
+ *
+ */
+static long pm8001_ioctl(struct file *file,
+		unsigned int cmd, unsigned long arg)
+{
+	u32 ret = -EACCES;
+	struct pm8001_hba_info *pm8001_ha;
+	struct ioctl_header header;
+
+	pm8001_ha = file->private_data;
+
+	switch (cmd) {
+	case ADPT_IOCTL_INFO:
+		ret = pm8001_info_ioctl(pm8001_ha, arg);
+		break;
+	default:
+		ret = ADPT_IOCTL_CALL_INVALID_CODE;
+	}
+
+	if (ret == 0)
+		return ret;
+	header.return_code = ret;
+	ret = -EACCES;
+	if (copy_to_user((void *)arg, (void *)&header,
+				sizeof(struct ioctl_header))) {
+		PM8001_FAIL_DBG(pm8001_ha,
+				pm8001_printk("copy_to_user failed\n"));
+	}
+	return ret;
+}
+
+static const struct file_operations pm8001_fops = {
+	.owner		= THIS_MODULE,
+	.open		= pm8001_open,
+	.release	= pm8001_close,
+	.unlocked_ioctl	= pm8001_ioctl,
+};
+
+/**
+ * pm8001_setup_chrdev - register char device
+ * Return value:
+ * 0 in case of success, otherwise non-zero value
+ */
+int pm8001_setup_chrdev(void)
+{
+	pm80xx_major = register_chrdev(0, DRV_NAME, &pm8001_fops);
+	if (pm80xx_major < 0) {
+		pr_warn("pm8001: unable to register %s  device.\n",
+				DRV_NAME);
+		return pm80xx_major;
+	}
+	return 0;
+}
+
+/**
+ * pm8001_release_chrdev - unregisters per-adapter management interface
+ * Return value:
+ * none
+ */
+void pm8001_release_chrdev(void)
+{
+	if (pm80xx_major > -1) {
+		unregister_chrdev(pm80xx_major, DRV_NAME);
+		pm80xx_major = -1;
+	}
+}
diff --git a/drivers/scsi/pm8001/pm8001_ctl.h b/drivers/scsi/pm8001/pm8001_ctl.h
index d0d43a250b9e..f0f8b1deae27 100644
--- a/drivers/scsi/pm8001/pm8001_ctl.h
+++ b/drivers/scsi/pm8001/pm8001_ctl.h
@@ -59,5 +59,38 @@
 #define SYSFS_OFFSET                    1024
 #define PM80XX_IB_OB_QUEUE_SIZE         (32 * 1024)
 #define PM8001_IB_OB_QUEUE_SIZE         (16 * 1024)
+
+#define ADPT_IOCTL_CALL_SUCCESS		0x00
+#define ADPT_IOCTL_CALL_FAILED		0x01
+#define ADPT_IOCTL_CALL_INVALID_CODE	0x03
+
+struct ioctl_header {
+	u32 io_controller_num;
+	u32 length;
+	u32 return_code;
+	u32 timeout;
+	u16 direction;
+};
+
+struct ioctl_drv_info {
+	u8	sz_name[64];
+	u16	usmajor_revision;
+	u16	usminor_revision;
+	u16	usbuild_revision;
+	u16	reserved0;
+	u32	maxdevices;
+	u32	maxoutstandingIO;
+	u32	reserved[16];
+};
+
+struct ioctl_info_buffer {
+	struct ioctl_header	header;
+	struct ioctl_drv_info	information;
+};
+
+#define ADPT_IOCTL_INFO _IOR(ADPT_MAGIC_NUMBER, 0, struct ioctl_info_buffer *)
+
+#define ADPT_MAGIC_NUMBER	'm'
+
 #endif /* PM8001_CTL_H_INCLUDED */
 
diff --git a/drivers/scsi/pm8001/pm8001_init.c b/drivers/scsi/pm8001/pm8001_init.c
index 775517f9b39d..25e74f1dbd0c 100644
--- a/drivers/scsi/pm8001/pm8001_init.c
+++ b/drivers/scsi/pm8001/pm8001_init.c
@@ -1421,6 +1421,9 @@ static int __init pm8001_init(void)
 	pm8001_stt = sas_domain_attach_transport(&pm8001_transport_ops);
 	if (!pm8001_stt)
 		goto err_wq;
+	rc = pm8001_setup_chrdev();
+	if (rc)
+		goto err_ctl;
 	rc = pci_register_driver(&pm8001_pci_driver);
 	if (rc)
 		goto err_tp;
@@ -1428,6 +1431,8 @@ static int __init pm8001_init(void)
 
 err_tp:
 	sas_release_transport(pm8001_stt);
+err_ctl:
+	pm8001_release_chrdev();
 err_wq:
 	destroy_workqueue(pm8001_wq);
 err:
diff --git a/drivers/scsi/pm8001/pm8001_sas.h b/drivers/scsi/pm8001/pm8001_sas.h
index 93438c8f67da..479aac34d7cc 100644
--- a/drivers/scsi/pm8001/pm8001_sas.h
+++ b/drivers/scsi/pm8001/pm8001_sas.h
@@ -59,6 +59,9 @@
 
 #define DRV_NAME		"pm80xx"
 #define DRV_VERSION		"0.1.39"
+#define DRV_MAJOR		1
+#define DRV_MINOR		3
+#define DRV_BUILD		0
 #define PM8001_FAIL_LOGGING	0x01 /* Error message logging */
 #define PM8001_INIT_LOGGING	0x02 /* driver init logging */
 #define PM8001_DISC_LOGGING	0x04 /* discovery layer logging */
@@ -745,6 +748,9 @@ ssize_t pm8001_get_gsm_dump(struct device *cdev, u32, char *buf);
 /* ctl shared API */
 extern struct device_attribute *pm8001_host_attrs[];
 
+int pm8001_setup_chrdev(void);
+void pm8001_release_chrdev(void);
+
 static inline void
 pm8001_ccb_task_free_done(struct pm8001_hba_info *pm8001_ha,
 			struct sas_task *task, struct pm8001_ccb_info *ccb,
-- 
2.16.3