Merge tag 'hwmon-for-v6.9-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-stagingHEADmaster

Pull hwmon fixes from Guenter Roeck:

 - pmbus/ucd9000: Increase chip access delay to avoid random access
   errors

 - corsair-cpro: Protect kernel code against parallel hidraw access from
   userspace

* tag 'hwmon-for-v6.9-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (pmbus/ucd9000) Increase delay from 250 to 500us
  hwmon: (corsair-cpro) Protect ccp->wait_input_report with a spinlock
  hwmon: (corsair-cpro) Use complete_all() instead of complete() in ccp_raw_event()
  hwmon: (corsair-cpro) Use a separate buffer for sending commands

2 files changed, 35 insertions, 16 deletions

diff --git a/drivers/hwmon/corsair-cpro.c b/drivers/hwmon/corsair-cpro.c
index a284a02839fbbd..3e63666a61bd6b 100644
--- a/drivers/hwmon/corsair-cpro.c
+++ b/drivers/hwmon/corsair-cpro.c
@@ -16,6 +16,7 @@
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/slab.h>
+#include <linux/spinlock.h>
 #include <linux/types.h>
 
 #define USB_VENDOR_ID_CORSAIR			0x1b1c
@@ -77,8 +78,11 @@
 struct ccp_device {
 	struct hid_device *hdev;
 	struct device *hwmon_dev;
+	/* For reinitializing the completion below */
+	spinlock_t wait_input_report_lock;
 	struct completion wait_input_report;
 	struct mutex mutex; /* whenever buffer is used, lock before send_usb_cmd */
+	u8 *cmd_buffer;
 	u8 *buffer;
 	int target[6];
 	DECLARE_BITMAP(temp_cnct, NUM_TEMP_SENSORS);
@@ -111,15 +115,23 @@ static int send_usb_cmd(struct ccp_device *ccp, u8 command, u8 byte1, u8 byte2,
 	unsigned long t;
 	int ret;
 
-	memset(ccp->buffer, 0x00, OUT_BUFFER_SIZE);
-	ccp->buffer[0] = command;
-	ccp->buffer[1] = byte1;
-	ccp->buffer[2] = byte2;
-	ccp->buffer[3] = byte3;
-
+	memset(ccp->cmd_buffer, 0x00, OUT_BUFFER_SIZE);
+	ccp->cmd_buffer[0] = command;
+	ccp->cmd_buffer[1] = byte1;
+	ccp->cmd_buffer[2] = byte2;
+	ccp->cmd_buffer[3] = byte3;
+
+	/*
+	 * Disable raw event parsing for a moment to safely reinitialize the
+	 * completion. Reinit is done because hidraw could have triggered
+	 * the raw event parsing and marked the ccp->wait_input_report
+	 * completion as done.
+	 */
+	spin_lock_bh(&ccp->wait_input_report_lock);
 	reinit_completion(&ccp->wait_input_report);
+	spin_unlock_bh(&ccp->wait_input_report_lock);
 
-	ret = hid_hw_output_report(ccp->hdev, ccp->buffer, OUT_BUFFER_SIZE);
+	ret = hid_hw_output_report(ccp->hdev, ccp->cmd_buffer, OUT_BUFFER_SIZE);
 	if (ret < 0)
 		return ret;
 
@@ -135,11 +147,12 @@ static int ccp_raw_event(struct hid_device *hdev, struct hid_report *report, u8
 	struct ccp_device *ccp = hid_get_drvdata(hdev);
 
 	/* only copy buffer when requested */
-	if (completion_done(&ccp->wait_input_report))
-		return 0;
-
-	memcpy(ccp->buffer, data, min(IN_BUFFER_SIZE, size));
-	complete(&ccp->wait_input_report);
+	spin_lock(&ccp->wait_input_report_lock);
+	if (!completion_done(&ccp->wait_input_report)) {
+		memcpy(ccp->buffer, data, min(IN_BUFFER_SIZE, size));
+		complete_all(&ccp->wait_input_report);
+	}
+	spin_unlock(&ccp->wait_input_report_lock);
 
 	return 0;
 }
@@ -492,7 +505,11 @@ static int ccp_probe(struct hid_device *hdev, const struct hid_device_id *id)
 	if (!ccp)
 		return -ENOMEM;
 
-	ccp->buffer = devm_kmalloc(&hdev->dev, OUT_BUFFER_SIZE, GFP_KERNEL);
+	ccp->cmd_buffer = devm_kmalloc(&hdev->dev, OUT_BUFFER_SIZE, GFP_KERNEL);
+	if (!ccp->cmd_buffer)
+		return -ENOMEM;
+
+	ccp->buffer = devm_kmalloc(&hdev->dev, IN_BUFFER_SIZE, GFP_KERNEL);
 	if (!ccp->buffer)
 		return -ENOMEM;
 
@@ -510,7 +527,9 @@ static int ccp_probe(struct hid_device *hdev, const struct hid_device_id *id)
 
 	ccp->hdev = hdev;
 	hid_set_drvdata(hdev, ccp);
+
 	mutex_init(&ccp->mutex);
+	spin_lock_init(&ccp->wait_input_report_lock);
 	init_completion(&ccp->wait_input_report);
 
 	hid_device_io_start(hdev);
diff --git a/drivers/hwmon/pmbus/ucd9000.c b/drivers/hwmon/pmbus/ucd9000.c
index 8d9d422450e5cf..d817c719b90bd5 100644
--- a/drivers/hwmon/pmbus/ucd9000.c
+++ b/drivers/hwmon/pmbus/ucd9000.c
@@ -80,11 +80,11 @@ struct ucd9000_debugfs_entry {
  * It has been observed that the UCD90320 randomly fails register access when
  * doing another access right on the back of a register write. To mitigate this
  * make sure that there is a minimum delay between a write access and the
- * following access. The 250us is based on experimental data. At a delay of
- * 200us the issue seems to go away. Add a bit of extra margin to allow for
+ * following access. The 500 is based on experimental data. At a delay of
+ * 350us the issue seems to go away. Add a bit of extra margin to allow for
  * system to system differences.
  */
-#define UCD90320_WAIT_DELAY_US 250
+#define UCD90320_WAIT_DELAY_US 500
 
 static inline void ucd90320_wait(const struct ucd9000_data *data)
 {