[Marius Zachmann <mail@mariuszachmann.de>]

Date: Sun, 12 May 2024 23:15:49 +0200
Subject: [PATCH] Add firmware and bootloader information

This patch adds:
- Reading the firmware and bootloader version of the device
- Debugfs entries: firmware_version and bootloader_version
- Updated documentation

Signed-off-by: Marius Zachmann <mail@mariuszachmann.de>
---
 Documentation/hwmon/corsair-cpro.rst |  8 +++
 drivers/hwmon/corsair-cpro.c         | 80 ++++++++++++++++++++++++++++
 2 files changed, 88 insertions(+)

diff --git a/Documentation/hwmon/corsair-cpro.rst b/Documentation/hwmon/corsair-cpro.rst
index 751f95476b57..11135d7ec6b9 100644
--- a/Documentation/hwmon/corsair-cpro.rst
+++ b/Documentation/hwmon/corsair-cpro.rst
@@ -39,3 +39,11 @@ fan[1-6]_target		Sets fan speed target rpm.
 pwm[1-6]		Sets the fan speed. Values from 0-255. Can only be read if pwm
 			was set directly.
 ======================= =====================================================================
+
+Debugfs entries
+---------------
+
+======================= ===========================
+firmware_version	Version of the firmware
+bootloader_version	Version of the bootloader
+======================= ===========================
diff --git a/drivers/hwmon/corsair-cpro.c b/drivers/hwmon/corsair-cpro.c
index 3e63666a61bd..4be8a98250a9 100644
--- a/drivers/hwmon/corsair-cpro.c
+++ b/drivers/hwmon/corsair-cpro.c
@@ -10,11 +10,13 @@
 
 #include <linux/bitops.h>
 #include <linux/completion.h>
+#include <linux/debugfs.h>
 #include <linux/hid.h>
 #include <linux/hwmon.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
+#include <linux/seq_file.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/types.h>
@@ -28,6 +30,8 @@
 #define LABEL_LENGTH		11
 #define REQ_TIMEOUT		300
 
+#define CTL_GET_FW_VER		0x02	/* returns the firmware version in bytes 1-3 */
+#define CTL_GET_BL_VER		0x06	/* returns the bootloader version in bytes 1-2 */
 #define CTL_GET_TMP_CNCT	0x10	/*
 					 * returns in bytes 1-4 for each temp sensor:
 					 * 0 not connected
@@ -78,6 +82,7 @@
 struct ccp_device {
 	struct hid_device *hdev;
 	struct device *hwmon_dev;
+	struct dentry *debugfs;
 	/* For reinitializing the completion below */
 	spinlock_t wait_input_report_lock;
 	struct completion wait_input_report;
@@ -88,6 +93,8 @@ struct ccp_device {
 	DECLARE_BITMAP(temp_cnct, NUM_TEMP_SENSORS);
 	DECLARE_BITMAP(fan_cnct, NUM_FANS);
 	char fan_label[6][LABEL_LENGTH];
+	u8 firmware_ver[3];
+	u8 bootloader_ver[2];
 };
 
 /* converts response error in buffer to errno */
@@ -496,6 +503,71 @@ static int get_temp_cnct(struct ccp_device *ccp)
 	return 0;
 }
 
+/* read firmware and bootloader version */
+static int get_fw_version(struct ccp_device *ccp)
+{
+	int ret;
+
+	ret = send_usb_cmd(ccp, CTL_GET_FW_VER, 0, 0, 0);
+	if (ret)
+		return ret;
+
+	ccp->firmware_ver[0] = ccp->buffer[1];
+	ccp->firmware_ver[1] = ccp->buffer[2];
+	ccp->firmware_ver[2] = ccp->buffer[3];
+
+	ret = send_usb_cmd(ccp, CTL_GET_BL_VER, 0, 0, 0);
+	if (ret)
+		return ret;
+
+	ccp->bootloader_ver[0] = ccp->buffer[1];
+	ccp->bootloader_ver[1] = ccp->buffer[2];
+
+	return 0;
+}
+
+#ifdef CONFIG_DEBUG_FS
+
+static int firmware_show(struct seq_file *seqf, void *unused)
+{
+	struct ccp_device *ccp = seqf->private;
+
+	seq_printf(seqf, "%d.%d.%d\n",
+		   ccp->firmware_ver[0],
+		   ccp->firmware_ver[1],
+		   ccp->firmware_ver[2]);
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(firmware);
+
+static int bootloader_show(struct seq_file *seqf, void *unused)
+{
+	struct ccp_device *ccp = seqf->private;
+
+	seq_printf(seqf, "%d.%d\n",
+		   ccp->bootloader_ver[0],
+		   ccp->bootloader_ver[1]);
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(bootloader);
+
+static void ccp_debugfs_init(struct ccp_device *ccp)
+{
+	ccp->debugfs = debugfs_create_dir("corsaircpro", NULL);
+	debugfs_create_file("firmware_version", 0444, ccp->debugfs, ccp, &firmware_fops);
+	debugfs_create_file("bootloader_version", 0444, ccp->debugfs, ccp, &bootloader_fops);
+}
+
+#else
+
+static void ccp_debugfs_init(struct ccp_device *ccp)
+{
+}
+
+#endif
+
 static int ccp_probe(struct hid_device *hdev, const struct hid_device_id *id)
 {
 	struct ccp_device *ccp;
@@ -542,6 +614,13 @@ static int ccp_probe(struct hid_device *hdev, const struct hid_device_id *id)
 	ret = get_fan_cnct(ccp);
 	if (ret)
 		goto out_hw_close;
+
+	ret = get_fw_version(ccp);
+	if (ret)
+		goto out_hw_close;
+
+	ccp_debugfs_init(ccp);
+
 	ccp->hwmon_dev = hwmon_device_register_with_info(&hdev->dev, "corsaircpro",
 							 ccp, &ccp_chip_info, NULL);
 	if (IS_ERR(ccp->hwmon_dev)) {
@@ -562,6 +641,7 @@ static void ccp_remove(struct hid_device *hdev)
 {
 	struct ccp_device *ccp = hid_get_drvdata(hdev);
 
+	debugfs_remove_recursive(ccp->debugfs);
 	hwmon_device_unregister(ccp->hwmon_dev);
 	hid_hw_close(hdev);
 	hid_hw_stop(hdev);
-- 
2.45.0