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From ae04984a5b4905b6326f9c1d94c554381d289634 Mon Sep 17 00:00:00 2001
From: 7Ji <pugokushin@gmail.com>
Date: Thu, 27 Apr 2023 23:46:33 +0800
Subject: [PATCH] drivers: auxdisplay: openvfd: improve dev write logic
---
drivers/auxdisplay/openvfd/openvfd_drv.c | 64 ++++++++++++++----------
1 file changed, 37 insertions(+), 27 deletions(-)
diff --git a/drivers/auxdisplay/openvfd/openvfd_drv.c b/drivers/auxdisplay/openvfd/openvfd_drv.c
index bd1a4c0d2..485fa48d9 100644
--- a/drivers/auxdisplay/openvfd/openvfd_drv.c
+++ b/drivers/auxdisplay/openvfd/openvfd_drv.c
@@ -216,6 +216,8 @@ static ssize_t openvfd_dev_read(struct file *filp, char __user * buf,
return ret;
}
+#define OPENVFD_DEV_WRITE_RAW_LENGTH 10
+
/**
* @param buf: Incoming LED codes.
* [0] Display indicators mask (wifi, eth, usb, etc.)
@@ -226,40 +228,48 @@ static ssize_t openvfd_dev_write(struct file *filp, const char __user * buf,
size_t count, loff_t * f_pos)
{
ssize_t status = 0;
- unsigned long missing;
static struct vfd_display_data data;
-
- if (count == sizeof(data)) {
- missing = copy_from_user(&data, buf, count);
- if (missing == 0 && count > 0) {
+ static unsigned char raw_data[OPENVFD_DEV_WRITE_RAW_LENGTH];
+
+ if (count > 0) {
+ void *data_p;
+ bool should_free = false;
+ bool write_raw = false;
+ switch (count) {
+ case sizeof data:
+ data_p = &data;
+ break;
+ case OPENVFD_DEV_WRITE_RAW_LENGTH:
+ data_p = raw_data;
+ write_raw = true;
+ break;
+ default:
+ if (!(data_p = kzalloc(count, GFP_KERNEL))) {
+ pr_error("openvfd_dev_write failed to allocate %ld bytes (raw_data)\n", count);
+ return -1;
+ }
+ should_free = true;
+ write_raw = true;
+ break;
+ }
+ if (!copy_from_user(data_p, buf, count)) {
+ size_t write_count = 0;
mutex_lock(&mutex);
- if (controller->write_display_data(&data))
- pr_dbg("openvfd_dev_write count : %ld\n", count);
- else {
- status = -1;
- pr_error("openvfd_dev_write failed to write %ld bytes (display_data)\n", count);
+ if (write_raw) {
+ write_count = controller->write_data((unsigned char*)raw_data, count);
+ } else {
+ write_count = controller->write_display_data(&data);
}
mutex_unlock(&mutex);
- }
- } else if (count > 0) {
- unsigned char *raw_data;
- pr_dbg2("openvfd_dev_write: count = %ld, sizeof(data) = %ld\n", count, sizeof(data));
- raw_data = kzalloc(count, GFP_KERNEL);
- if (raw_data) {
- missing = copy_from_user(raw_data, buf, count);
- mutex_lock(&mutex);
- if (controller->write_data((unsigned char*)raw_data, count))
- pr_dbg("openvfd_dev_write count : %ld\n", count);
- else {
+ if (write_count) {
+ pr_dbg("openvfd_dev_write %ld from %ld bytes\n", write_count, count);
+ } else {
status = -1;
- pr_error("openvfd_dev_write failed to write %ld bytes (raw_data)\n", count);
+ pr_error("openvfd_dev_write failed to write %ld bytes (display_data)\n", count);
}
- mutex_unlock(&mutex);
- kfree(raw_data);
}
- else {
- status = -1;
- pr_error("openvfd_dev_write failed to allocate %ld bytes (raw_data)\n", count);
+ if (should_free) {
+ kfree(data_p);
}
}
--
2.40.0
|