A recent LKML thread (http://lkml.indiana.edu/hypermail/linux/kernel/1112.3/00965.html)
discusses warnings that occur during a suspend/resume cycle. The driver
attempts to read the firmware file before userspace is ready, leading to the
following warning:
WARNING: at drivers/base/firmware_class.c:537 _request_firmware+0x3f6/0x420()
For rtl8192cu, the problem is fixed by storing the firmware in a global buffer
rather than one allocated per device. The usage count is increased when
suspending and decreased when resuming. This way, the firmware is retained
through a suspend/resume cycle, and does not have to be reread.
This patch should fix the bug reported in
https://bugzilla.redhat.com/show_bug.cgi?id=771002.
Note: This patch also touches rtl8192ce as the "firmware" loaded message
is now printed in the wrong place.
Reported-by: Mohammed Arafa <[email protected]>
Reported-by: Dave Jones <[email protected]>
Signed-off-by: Larry Finger <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Stable <[email protected]>
---
V2 - revised to avoid warning noted by Daniel Halperin.
---
John,
As I missed the V3.2 cutoff, this can be given normal -next processing.
Sorry for any problems that were caused.
Larry
---
Index: wireless-testing-new/drivers/net/wireless/rtlwifi/rtl8192c/fw_common.c
===================================================================
--- wireless-testing-new.orig/drivers/net/wireless/rtlwifi/rtl8192c/fw_common.c
+++ wireless-testing-new/drivers/net/wireless/rtlwifi/rtl8192c/fw_common.c
@@ -263,7 +263,6 @@ int rtl92c_download_fw(struct ieee80211_
if (!rtlhal->pfirmware)
return 1;
- pr_info("Loading firmware file %s\n", rtlpriv->cfg->fw_name);
pfwheader = (struct rtl92c_firmware_header *)rtlhal->pfirmware;
pfwdata = (u8 *) rtlhal->pfirmware;
fwsize = rtlhal->fwsize;
Index: wireless-testing-new/drivers/net/wireless/rtlwifi/rtl8192ce/sw.c
===================================================================
--- wireless-testing-new.orig/drivers/net/wireless/rtlwifi/rtl8192ce/sw.c
+++ wireless-testing-new/drivers/net/wireless/rtlwifi/rtl8192ce/sw.c
@@ -186,6 +186,7 @@ int rtl92c_init_sw_vars(struct ieee80211
memcpy(rtlpriv->rtlhal.pfirmware, firmware->data, firmware->size);
rtlpriv->rtlhal.fwsize = firmware->size;
release_firmware(firmware);
+ pr_info("rtl8192ce: Loaded firmware file %s\n", rtlpriv->cfg->fw_name);
return 0;
}
Index: wireless-testing-new/drivers/net/wireless/rtlwifi/rtl8192cu/sw.c
===================================================================
--- wireless-testing-new.orig/drivers/net/wireless/rtlwifi/rtl8192cu/sw.c
+++ wireless-testing-new/drivers/net/wireless/rtlwifi/rtl8192cu/sw.c
@@ -43,6 +43,8 @@
#include "hw.h"
#include <linux/vmalloc.h>
#include <linux/module.h>
+#include <linux/atomic.h>
+#include <linux/types.h>
MODULE_AUTHOR("Georgia <[email protected]>");
MODULE_AUTHOR("Ziv Huang <[email protected]>");
@@ -51,6 +53,10 @@ MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Realtek 8192C/8188C 802.11n USB wireless");
MODULE_FIRMWARE("rtlwifi/rtl8192cufw.bin");
+static char *rtl8192cu_firmware; /* pointer to firmware */
+static int firmware_size;
+static atomic_t usage_count;
+
static int rtl92cu_init_sw_vars(struct ieee80211_hw *hw)
{
struct rtl_priv *rtlpriv = rtl_priv(hw);
@@ -62,12 +68,21 @@ static int rtl92cu_init_sw_vars(struct i
rtlpriv->dm.disable_framebursting = 0;
rtlpriv->dm.thermalvalue = 0;
rtlpriv->dbg.global_debuglevel = rtlpriv->cfg->mod_params->debug;
- rtlpriv->rtlhal.pfirmware = vmalloc(0x4000);
- if (!rtlpriv->rtlhal.pfirmware) {
+
+ if (rtl8192cu_firmware) {
+ /* firmware already loaded - true for suspend/resume
+ * and multiple instances of the device */
+ rtlpriv->rtlhal.pfirmware = rtl8192cu_firmware;
+ rtlpriv->rtlhal.fwsize = firmware_size;
+ return 0;
+ }
+ rtl8192cu_firmware = vzalloc(0x4000);
+ if (!rtl8192cu_firmware) {
RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG,
"Can't alloc buffer for fw\n");
return 1;
}
+
/* request fw */
err = request_firmware(&firmware, rtlpriv->cfg->fw_name,
rtlpriv->io.dev);
@@ -82,9 +97,14 @@ static int rtl92cu_init_sw_vars(struct i
release_firmware(firmware);
return 1;
}
- memcpy(rtlpriv->rtlhal.pfirmware, firmware->data, firmware->size);
+ pr_info("rtl8192cu: Loaded firmware from file %s\n",
+ rtlpriv->cfg->fw_name);
+ memcpy(rtl8192cu_firmware, firmware->data, firmware->size);
+ firmware_size = firmware->size;
rtlpriv->rtlhal.fwsize = firmware->size;
+ rtlpriv->rtlhal.pfirmware = rtl8192cu_firmware;
release_firmware(firmware);
+ atomic_inc(&usage_count);
return 0;
}
@@ -93,12 +113,30 @@ static void rtl92cu_deinit_sw_vars(struc
{
struct rtl_priv *rtlpriv = rtl_priv(hw);
- if (rtlpriv->rtlhal.pfirmware) {
- vfree(rtlpriv->rtlhal.pfirmware);
+ atomic_dec(&usage_count);
+ if (!atomic_read(&usage_count) && rtlpriv->rtlhal.pfirmware) {
+ vfree(rtl8192cu_firmware);
+ rtl8192cu_firmware = NULL;
rtlpriv->rtlhal.pfirmware = NULL;
}
}
+#ifdef CONFIG_PM_SLEEP
+static int rtl8192cu_usb_suspend(struct usb_interface *pusb_intf,
+ pm_message_t message)
+{
+ /* Increase usage_count to Save loaded fw across suspend/resume */
+ atomic_inc(&usage_count);
+ return 0;
+}
+
+static int rtl8192cu_usb_resume(struct usb_interface *pusb_intf)
+{
+ atomic_dec(&usage_count); /* after resume, decrease usage count */
+ return 0;
+}
+#endif
+
static struct rtl_hal_ops rtl8192cu_hal_ops = {
.init_sw_vars = rtl92cu_init_sw_vars,
.deinit_sw_vars = rtl92cu_deinit_sw_vars,
@@ -374,11 +412,10 @@ static struct usb_driver rtl8192cu_drive
.disconnect = rtl_usb_disconnect,
.id_table = rtl8192c_usb_ids,
-#ifdef CONFIG_PM
- /* .suspend = rtl_usb_suspend, */
- /* .resume = rtl_usb_resume, */
- /* .reset_resume = rtl8192c_resume, */
-#endif /* CONFIG_PM */
+#ifdef CONFIG_PM_SLEEP
+ .suspend = rtl8192cu_usb_suspend,
+ .resume = rtl8192cu_usb_resume,
+#endif /* CONFIG_PM_SLEEP */
#ifdef CONFIG_AUTOSUSPEND
.supports_autosuspend = 1,
#endif
John,
Please drop the patch with this subject. I think I can do a better job than this.
Larry
Commit message:
=============================================
A recent LKML thread
(http://lkml.indiana.edu/hypermail/linux/kernel/1112.3/00965.html)
discusses warnings that occur during a suspend/resume cycle. The driver
attempts to read the firmware file before userspace is ready, leading to the
following warning:
WARNING: at drivers/base/firmware_class.c:537 _request_firmware+0x3f6/0x420()
For rtl8192cu, the problem is fixed by storing the firmware in a global buffer
rather than one allocated per device. The usage count is increased when
suspending and decreased when resuming. This way, the firmware is retained
through a suspend/resume cycle, and does not have to be reread.
This patch should fix the bug reported in
https://bugzilla.redhat.com/show_bug.cgi?id=771002.
Note: This patch also touches rtl8192ce as the "firmware" loaded message
is now printed in the wrong place.
Reported-by: Mohammed Arafa <[email protected]>
Reported-by: Dave Jones <[email protected]>
Signed-off-by: Larry Finger <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Stable <[email protected]>
---
V2 - revised to avoid warning noted by Daniel Halperin.
---
On 1/9/2012 3:46 PM, Larry Finger wrote:
>
> +#ifdef CONFIG_PM_SLEEP
> +static int rtl8192cu_usb_suspend(struct usb_interface *pusb_intf,
> + pm_message_t message)
> +{
> + /* Increase usage_count to Save loaded fw across suspend/resume */
> + atomic_inc(&usage_count);
> + return 0;
> +}
> +
>
If firmware is not actively loaded on a 0 to 1 transition of
usage_count, what good is this
atomic_inc doing?
I admit that my understanding is probably at fault, but it looks odd.
I took off list because this message is probably just noise.
Troy