diff options
Diffstat (limited to 'target/linux/s3c24xx/patches-2.6.24/1271-always-call-resume-dependencies.patch.patch')
| -rw-r--r-- | target/linux/s3c24xx/patches-2.6.24/1271-always-call-resume-dependencies.patch.patch | 255 |
1 files changed, 255 insertions, 0 deletions
diff --git a/target/linux/s3c24xx/patches-2.6.24/1271-always-call-resume-dependencies.patch.patch b/target/linux/s3c24xx/patches-2.6.24/1271-always-call-resume-dependencies.patch.patch new file mode 100644 index 0000000000..f484734563 --- /dev/null +++ b/target/linux/s3c24xx/patches-2.6.24/1271-always-call-resume-dependencies.patch.patch @@ -0,0 +1,255 @@ +From 36879992de8774cbf8686740bbda383cc6fbdcbb Mon Sep 17 00:00:00 2001 +From: \\\\\\\"Mike (mwester)\\\\\\ <mwester@dls.net> +Date: Mon, 11 Aug 2008 20:16:09 +0100 +Subject: [PATCH] always-call-resume-dependencies.patch + +Attached is a patch that has greatly reduced the frequency of failures +to resume (due to an oops from the glamo resume handler), and the +dreaded "white screen after resume". I can't say that it fixes all of +these, although I have yet to see the white-screen since applying this +patch and suspending/resuming several hundred times (with the 30-second +suspend on the 2008.8 image and the endless stream of GSM error messages +generated by something in that image, it has proved to be very useful to +do an automated stress test!) + +This patch will apply to stable, and should make stable slightly more, +well, "stable". + +[Feel free to remove the debug messages if someone feels strongly about +that; I left them in because I think they might be useful in triaging +further crashes; I'm not at all convinced that this patch will fix all +the cases of resume failures.] + +[[And, yes, this is ugly, really ugly.]] + +[[[Oh yeah - there's still one extreme case that will result in an oops: + if a dependent driver is built as a module, and it is unloaded, and it +happened that the preceding suspend/resume was aborted, and that abort +happened between the dependent driver and the driver upon which it is +dependent, then a list entry will be left behind referencing the +unloaded module. There's just no good way to fix that given the way the +resume dependency plumbing is connected up right now, so just avoid +using modules for any of the drivers involved in the resume dependency +stuff.]]] + +Regards, +Mike (mwester) +commit 905d2fc9c45f622418ce9ef4e67c23453aab7571 +Author: Mike Westerhof <mwester@dls.net> +Date: Mon Aug 11 11:11:25 2008 -0500 + + always-call-resume-dependencies.patch + + Ensure that a dependent resume handler is always executed, + even if the resume handler for driver upon which it is + dependent never suspends (and therefore never resumes either). + Also make sure that we do not end up with duplicate + dependencies registered, something that can happen if the + suspend is aborted due to driver failure or an early resume + (such as occurs when the GSM interrupts during suspend). + + Signed-off-by: Mike Westerhof <mwester@dls.net> +--- + drivers/i2c/chips/pcf50633.c | 6 +++++ + drivers/mfd/glamo/glamo-core.c | 5 ++++ + drivers/mfd/glamo/glamo-core.h | 1 + + drivers/serial/s3c2410.c | 7 ++++++ + include/linux/resume-dependency.h | 38 ++++++++++++++++++++++++++++++++++++- + 5 files changed, 56 insertions(+), 1 deletions(-) + +diff --git a/drivers/i2c/chips/pcf50633.c b/drivers/i2c/chips/pcf50633.c +index 98c254c..b90ea8c 100644 +--- a/drivers/i2c/chips/pcf50633.c ++++ b/drivers/i2c/chips/pcf50633.c +@@ -183,6 +183,7 @@ struct pcf50633_data { + } standby_regs; + + struct resume_dependency resume_dependency; ++ int is_suspended; + + #endif + }; +@@ -2366,6 +2367,8 @@ void pcf50633_register_resume_dependency(struct pcf50633_data *pcf, + struct resume_dependency *dep) + { + register_resume_dependency(&pcf->resume_dependency, dep); ++ if (pcf->is_suspended) ++ activate_all_resume_dependencies(&pcf->resume_dependency); + } + EXPORT_SYMBOL_GPL(pcf50633_register_resume_dependency); + +@@ -2462,6 +2465,8 @@ static int pcf50633_suspend(struct device *dev, pm_message_t state) + + mutex_unlock(&pcf->lock); + ++ pcf->is_suspended = 1; ++ activate_all_resume_dependencies(&pcf->resume_dependency); + return 0; + } + +@@ -2590,6 +2595,7 @@ static int pcf50633_resume(struct device *dev) + get_device(&pcf->client.dev); + pcf50633_work(&pcf->work); + ++ pcf->is_suspended = 0; + callback_all_resume_dependencies(&pcf->resume_dependency); + + return 0; +diff --git a/drivers/mfd/glamo/glamo-core.c b/drivers/mfd/glamo/glamo-core.c +index c094a8c..e310382 100644 +--- a/drivers/mfd/glamo/glamo-core.c ++++ b/drivers/mfd/glamo/glamo-core.c +@@ -1248,6 +1248,8 @@ void glamo_register_resume_dependency(struct resume_dependency * + { + register_resume_dependency(&glamo_handle->resume_dependency, + resume_dependency); ++ if (glamo_handle->is_suspended) ++ activate_all_resume_dependencies(&glamo_handle->resume_dependency); + } + EXPORT_SYMBOL_GPL(glamo_register_resume_dependency); + +@@ -1255,12 +1257,15 @@ EXPORT_SYMBOL_GPL(glamo_register_resume_dependency); + static int glamo_suspend(struct platform_device *pdev, pm_message_t state) + { + glamo_power(glamo_handle, GLAMO_POWER_SUSPEND); ++ glamo_handle->is_suspended = 1; ++ activate_all_resume_dependencies(&glamo_handle->resume_dependency); + return 0; + } + + static int glamo_resume(struct platform_device *pdev) + { + glamo_power(glamo_handle, GLAMO_POWER_ON); ++ glamo_handle->is_suspended = 0; + callback_all_resume_dependencies(&glamo_handle->resume_dependency); + + return 0; +diff --git a/drivers/mfd/glamo/glamo-core.h b/drivers/mfd/glamo/glamo-core.h +index d3f4309..ac5eacf 100644 +--- a/drivers/mfd/glamo/glamo-core.h ++++ b/drivers/mfd/glamo/glamo-core.h +@@ -32,6 +32,7 @@ struct glamo_core { + struct resume_dependency resume_dependency; + u32 engine_enabled_bitfield; + u32 engine_enabled_bitfield_suspend; ++ int is_suspended; + }; + + struct glamo_script { +diff --git a/drivers/serial/s3c2410.c b/drivers/serial/s3c2410.c +index 2a388cf..3b1c07b 100644 +--- a/drivers/serial/s3c2410.c ++++ b/drivers/serial/s3c2410.c +@@ -116,6 +116,7 @@ struct s3c24xx_uart_port { + struct uart_port port; + + struct resume_dependency resume_dependency; ++ int is_suspended; + }; + + +@@ -1188,10 +1189,13 @@ static int s3c24xx_serial_remove(struct platform_device *dev) + static int s3c24xx_serial_suspend(struct platform_device *dev, pm_message_t state) + { + struct uart_port *port = s3c24xx_dev_to_port(&dev->dev); ++ struct s3c24xx_uart_port *ourport = to_ourport(port); + + if (port) + uart_suspend_port(&s3c24xx_uart_drv, port); + ++ activate_all_resume_dependencies(&ourport->resume_dependency); ++ ourport->is_suspended = 1; + return 0; + } + +@@ -1202,6 +1206,8 @@ void s3c24xx_serial_register_resume_dependency(struct resume_dependency * + + register_resume_dependency(&ourport->resume_dependency, + resume_dependency); ++ if (ourport->is_suspended) ++ activate_all_resume_dependencies(&ourport->resume_dependency); + } + EXPORT_SYMBOL(s3c24xx_serial_register_resume_dependency); + +@@ -1218,6 +1224,7 @@ static int s3c24xx_serial_resume(struct platform_device *dev) + uart_resume_port(&s3c24xx_uart_drv, port); + } + ++ ourport->is_suspended = 0; + callback_all_resume_dependencies(&ourport->resume_dependency); + + return 0; +diff --git a/include/linux/resume-dependency.h b/include/linux/resume-dependency.h +index e0c0f33..959cadd 100644 +--- a/include/linux/resume-dependency.h ++++ b/include/linux/resume-dependency.h +@@ -38,6 +38,7 @@ struct resume_dependency { + */ + + #define init_resume_dependency_list(_head) \ ++ printk(KERN_ERR "##### init_resume_dependency_list(head=%p)\n", (_head)); \ + INIT_LIST_HEAD(&(_head)->list); + + +@@ -48,7 +49,18 @@ struct resume_dependency { + */ + + #define register_resume_dependency(_head, _dep) { \ +- (_dep)->called_flag = 0; \ ++ struct list_head *_pos, *_q; \ ++ struct resume_dependency *_d; \ ++\ ++ printk(KERN_ERR "##### register_resume_dependency(head=%p, dep=%p)\n", (_head), (_dep)); \ ++ (_dep)->called_flag = 1; \ ++ list_for_each_safe(_pos, _q, &((_head)->list)) { \ ++ _d = list_entry(_pos, struct resume_dependency, list); \ ++ if (_d == (_dep)) { \ ++ list_del(_pos); \ ++ printk(KERN_ERR "##### duplicate dependency removed first\n"); \ ++ } \ ++ } \ + list_add(&(_dep)->list, &(_head)->list); \ + } + +@@ -61,14 +73,38 @@ struct resume_dependency { + struct list_head *_pos, *_q; \ + struct resume_dependency *_dep; \ + \ ++ printk(KERN_ERR "##### callback_all_resume_dependencies(head=%p)\n", (_head)); \ + list_for_each_safe(_pos, _q, &((_head)->list)) { \ + _dep = list_entry(_pos, struct resume_dependency, list); \ ++ printk(KERN_ERR "##### callback list entry (head=%p, dep=%p)\n", (_head), (_dep)); \ + _dep->called_flag = 1; \ ++ printk(KERN_ERR "##### callback=%p(context=%p))\n", (_dep->callback),(_dep->context)); \ + (_dep->callback)(_dep->context); \ + list_del(_pos); \ + } \ + } + ++/* When a dependency is added, it is not actually active; the dependent resume ++ * handler will function as normal. The dependency is activated by the suspend ++ * handler for the driver that will be doing the callbacks. This ensures that ++ * if the suspend is aborted for any reason (error, driver busy, etc), that all ++ * suspended drivers will resume, even if the driver upon which they are dependent ++ * did not suspend, and hence will not resume, and thus would be unable to perform ++ * the callbacks. ++ */ ++ ++#define activate_all_resume_dependencies(_head) { \ ++ struct list_head *_pos, *_q; \ ++ struct resume_dependency *_dep; \ ++\ ++ printk(KERN_ERR "##### activate_all_resume_dependencies(head=%p)\n", (_head)); \ ++ list_for_each_safe(_pos, _q, &((_head)->list)) { \ ++ _dep = list_entry(_pos, struct resume_dependency, list); \ ++ printk(KERN_ERR "##### activating callback list entry (head=%p, dep=%p)\n", (_head), (_dep)); \ ++ _dep->called_flag = 0; \ ++ } \ ++} ++ + /* if your resume action is dependent on multiple drivers being resumed already, + * register the same callback with each driver you are dependent on, and check + * .called_flag for all of the struct resume_dependency. When they are all 1 +-- +1.5.6.5 + |