From 9bed4563ebd6ac99594f39ab004bf4411b904434 Mon Sep 17 00:00:00 2001 From: Andy Green Date: Fri, 25 Jul 2008 23:06:13 +0100 Subject: [PATCH] fix-pcf50633-usb-curlim-workqueue-migration.patch pcf50633 needs to take responsibility for managing current limit changes asycnhrnously, ie, from USB stack enumeration. It's a feature of pcf50633 not mach-gta02.c, and we can do better with taking care about keeping it from firing at a bad time in there too. Signed-off-by: Andy Green --- arch/arm/mach-s3c2440/mach-gta02.c | 23 +-------- drivers/i2c/chips/pcf50633.c | 96 ++++++++++++++++++++++++++++++++++++ include/linux/pcf50633.h | 5 ++ 3 files changed, 103 insertions(+), 21 deletions(-) diff --git a/arch/arm/mach-s3c2440/mach-gta02.c b/arch/arm/mach-s3c2440/mach-gta02.c index 64d275d..accdbc5 100644 --- a/arch/arm/mach-s3c2440/mach-gta02.c +++ b/arch/arm/mach-s3c2440/mach-gta02.c @@ -813,29 +813,11 @@ static void gta02_udc_command(enum s3c2410_udc_cmd_e cmd) } } -/* use a work queue, since I2C API inherently schedules - * and we get called in hardirq context from UDC driver */ - -struct vbus_draw { - struct work_struct work; - int ma; -}; -static struct vbus_draw gta02_udc_vbus_drawer; - -static void __gta02_udc_vbus_draw(struct work_struct *work) -{ - if (!pcf50633_global) { - printk(KERN_ERR "pcf50633 not initialized yet, can't change " - "vbus_draw\n"); - return; - } - pcf50633_usb_curlim_set(pcf50633_global, gta02_udc_vbus_drawer.ma); -} +/* get PMU to set USB current limit accordingly */ static void gta02_udc_vbus_draw(unsigned int ma) { - gta02_udc_vbus_drawer.ma = ma; - schedule_work(>a02_udc_vbus_drawer.work); + pcf50633_notify_usb_current_limit_change(pcf50633_global, ma); } static struct s3c2410_udc_mach_info gta02_udc_cfg = { @@ -1478,7 +1460,6 @@ static void __init gta02_machine_init(void) s3c2410_gpio_setpin(S3C2410_GPD13, 1); s3c2410_gpio_cfgpin(S3C2410_GPD13, S3C2410_GPIO_OUTPUT); - INIT_WORK(>a02_udc_vbus_drawer.work, __gta02_udc_vbus_draw); s3c24xx_udc_set_platdata(>a02_udc_cfg); set_s3c2410ts_info(>a02_ts_cfg); diff --git a/drivers/i2c/chips/pcf50633.c b/drivers/i2c/chips/pcf50633.c index 645cbbb..58f6ffc 100644 --- a/drivers/i2c/chips/pcf50633.c +++ b/drivers/i2c/chips/pcf50633.c @@ -125,6 +125,7 @@ struct pcf50633_data { int have_been_suspended; int usb_removal_count; unsigned char pcfirq_resume[5]; + int probe_completed; /* if he pulls battery while charging, we notice that and correctly * report that the charger is idle. But there is no interrupt that @@ -138,6 +139,12 @@ struct pcf50633_data { int usb_removal_count_nobat; int jiffies_last_bat_ins; + /* current limit notification handler stuff */ + struct mutex working_lock_usb_curlimit; + struct work_struct work_usb_curlimit; + int pending_curlimit; + int usb_removal_count_usb_curlimit; + int last_curlim_set; int coldplug_done; /* cleared by probe, set by first work service */ @@ -603,6 +610,92 @@ static void add_request_to_adc_queue(struct pcf50633_data *pcf, trigger_next_adc_job_if_any(pcf); } +/* + * we get run to handle servicing the async notification from USB stack that + * we got enumerated and allowed to draw a particular amount of current + */ + +static void pcf50633_work_usbcurlim(struct work_struct *work) +{ + struct pcf50633_data *pcf = + container_of(work, struct pcf50633_data, work_usb_curlimit); + + mutex_lock(&pcf->working_lock_usb_curlimit); + + dev_info(&pcf->client.dev, "pcf50633_work_usbcurlim\n"); + + if (!pcf->probe_completed) + goto reschedule; + + /* we got a notification from USB stack before we completed resume... + * that can only make trouble, reschedule for a retry + */ + if (pcf->have_been_suspended && (pcf->have_been_suspended < 3)) + goto reschedule; + + /* + * did he pull USB before we managed to set the limit? + */ + if (pcf->usb_removal_count_usb_curlimit != pcf->usb_removal_count) + goto bail; + + /* OK let's set the requested limit and finish */ + + dev_info(&pcf->client.dev, "pcf50633_work_usbcurlim setting %dmA\n", + pcf->pending_curlimit); + pcf50633_usb_curlim_set(pcf, pcf->pending_curlimit); + +bail: + mutex_unlock(&pcf->working_lock_usb_curlimit); + return; + +reschedule: + dev_info(&pcf->client.dev, "pcf50633_work_usbcurlim rescheduling\n"); + if (!schedule_work(&pcf->work_usb_curlimit)) + dev_err(&pcf->client.dev, "work item may be lost\n"); + + mutex_unlock(&pcf->working_lock_usb_curlimit); + /* don't spew, delaying whatever else is happening */ + msleep(1); +} + + +/* this is an export to allow machine to set USB current limit according to + * notifications of USB stack about enumeration state. We spawn a work + * function to handle the actual setting, because suspend / resume and such + * can be in a bad state since this gets called externally asychronous to + * anything else going on in pcf50633. + */ + +int pcf50633_notify_usb_current_limit_change(struct pcf50633_data *pcf, + unsigned int ma) +{ + /* can happen if he calls with pcf50633_global before probe + * have to bail with error since we can't even schedule the work + */ + if (!pcf) { + dev_err(&pcf->client.dev, + "pcf50633_notify_usb_current_limit_change " + "called with NULL pcf\n"); + return -EBUSY; + } + + dev_info(&pcf->client.dev, + "pcf50633_notify_usb_current_limit_change %dmA\n", ma); + + /* prepare to detect USB power removal before we complete */ + pcf->usb_removal_count_usb_curlimit = pcf->usb_removal_count; + + pcf->pending_curlimit = ma; + + if (!schedule_work(&pcf->work_usb_curlimit)) + dev_err(&pcf->client.dev, "work item may be lost\n"); + + return 0; +} +EXPORT_SYMBOL_GPL(pcf50633_notify_usb_current_limit_change); + + /* we are run when we see a NOBAT situation, because there is no interrupt * source in pcf50633 that triggers on resuming charging. It watches to see * if charging resumes, it reassesses the charging source if it does. If the @@ -1960,8 +2053,10 @@ static int pcf50633_detect(struct i2c_adapter *adapter, int address, int kind) mutex_init(&data->lock); mutex_init(&data->working_lock); mutex_init(&data->working_lock_nobat); + mutex_init(&data->working_lock_usb_curlimit); INIT_WORK(&data->work, pcf50633_work); INIT_WORK(&data->work_nobat, pcf50633_work_nobat); + INIT_WORK(&data->work_usb_curlimit, pcf50633_work_usbcurlim); data->irq = irq; data->working = 0; data->onkey_seconds = -1; @@ -2060,6 +2155,7 @@ static int pcf50633_detect(struct i2c_adapter *adapter, int address, int kind) } apm_get_power_status = pcf50633_get_power_status; + data->probe_completed = 1; #ifdef CONFIG_MACH_NEO1973_GTA02 if (machine_is_neo1973_gta02()) { diff --git a/include/linux/pcf50633.h b/include/linux/pcf50633.h index 0522d92..fa1c7e8 100644 --- a/include/linux/pcf50633.h +++ b/include/linux/pcf50633.h @@ -129,6 +129,11 @@ extern void pcf50633_register_resume_dependency(struct pcf50633_data *pcf, struct resume_dependency *dep); +extern int +pcf50633_notify_usb_current_limit_change(struct pcf50633_data *pcf, + unsigned int ma); + + /* 0 = initialized and resumed and ready to roll, !=0 = either not * initialized or not resumed yet */ -- 1.5.6.3