target/linux/s3c24xx/patches-2.6.26/1167-fix-pcf50633-usb-curlim-workqueue-migration.patch.patch

   1 From 9bed4563ebd6ac99594f39ab004bf4411b904434 Mon Sep 17 00:00:00 2001
   2 From: Andy Green <andy@openmoko.com>
   3 Date: Fri, 25 Jul 2008 23:06:13 +0100
   4 Subject: [PATCH] fix-pcf50633-usb-curlim-workqueue-migration.patch
   5
   6 pcf50633 needs to take responsibility for managing current limit
   7 changes asycnhrnously, ie, from USB stack enumeration.  It's a feature of
   8 pcf50633 not mach-gta02.c, and we can do better with taking care about
   9 keeping it from firing at a bad time in there too.
  10
  11 Signed-off-by: Andy Green <andy@openmoko.com>
  12 ---
  13  arch/arm/mach-s3c2440/mach-gta02.c |   23 +--------
  14  drivers/i2c/chips/pcf50633.c       |   96 ++++++++++++++++++++++++++++++++++++
  15  include/linux/pcf50633.h           |    5 ++
  16  3 files changed, 103 insertions(+), 21 deletions(-)
  17
  18 diff --git a/arch/arm/mach-s3c2440/mach-gta02.c b/arch/arm/mach-s3c2440/mach-gta02.c
  19 index 64d275d..accdbc5 100644
  20 --- a/arch/arm/mach-s3c2440/mach-gta02.c
  21 +++ b/arch/arm/mach-s3c2440/mach-gta02.c
  22 @@ -813,29 +813,11 @@ static void gta02_udc_command(enum s3c2410_udc_cmd_e cmd)
  23         }
  24  }
  25
  26 -/* use a work queue, since I2C API inherently schedules
  27 - * and we get called in hardirq context from UDC driver */
  28 -
  29 -struct vbus_draw {
  30 -       struct work_struct work;
  31 -       int ma;
  32 -};
  33 -static struct vbus_draw gta02_udc_vbus_drawer;
  34 -
  35 -static void __gta02_udc_vbus_draw(struct work_struct *work)
  36 -{
  37 -       if (!pcf50633_global) {
  38 -               printk(KERN_ERR  "pcf50633 not initialized yet, can't change "
  39 -                      "vbus_draw\n");
  40 -               return;
  41 -       }
  42 -       pcf50633_usb_curlim_set(pcf50633_global, gta02_udc_vbus_drawer.ma);
  43 -}
  44 +/* get PMU to set USB current limit accordingly */
  45
  46  static void gta02_udc_vbus_draw(unsigned int ma)
  47  {
  48 -       gta02_udc_vbus_drawer.ma = ma;
  49 -       schedule_work(&gta02_udc_vbus_drawer.work);
  50 +       pcf50633_notify_usb_current_limit_change(pcf50633_global, ma);
  51  }
  52
  53  static struct s3c2410_udc_mach_info gta02_udc_cfg = {
  54 @@ -1478,7 +1460,6 @@ static void __init gta02_machine_init(void)
  55         s3c2410_gpio_setpin(S3C2410_GPD13, 1);
  56         s3c2410_gpio_cfgpin(S3C2410_GPD13, S3C2410_GPIO_OUTPUT);
  57
  58 -       INIT_WORK(&gta02_udc_vbus_drawer.work, __gta02_udc_vbus_draw);
  59         s3c24xx_udc_set_platdata(&gta02_udc_cfg);
  60         set_s3c2410ts_info(&gta02_ts_cfg);
  61
  62 diff --git a/drivers/i2c/chips/pcf50633.c b/drivers/i2c/chips/pcf50633.c
  63 index 645cbbb..58f6ffc 100644
  64 --- a/drivers/i2c/chips/pcf50633.c
  65 +++ b/drivers/i2c/chips/pcf50633.c
  66 @@ -125,6 +125,7 @@ struct pcf50633_data {
  67         int have_been_suspended;
  68         int usb_removal_count;
  69         unsigned char pcfirq_resume[5];
  70 +       int probe_completed;
  71
  72         /* if he pulls battery while charging, we notice that and correctly
  73          * report that the charger is idle.  But there is no interrupt that
  74 @@ -138,6 +139,12 @@ struct pcf50633_data {
  75         int usb_removal_count_nobat;
  76         int jiffies_last_bat_ins;
  77
  78 +       /* current limit notification handler stuff */
  79 +       struct mutex working_lock_usb_curlimit;
  80 +       struct work_struct work_usb_curlimit;
  81 +       int pending_curlimit;
  82 +       int usb_removal_count_usb_curlimit;
  83 +
  84         int last_curlim_set;
  85
  86         int coldplug_done; /* cleared by probe, set by first work service */
  87 @@ -603,6 +610,92 @@ static void add_request_to_adc_queue(struct pcf50633_data *pcf,
  88                 trigger_next_adc_job_if_any(pcf);
  89  }
  90
  91 +/*
  92 + * we get run to handle servicing the async notification from USB stack that
  93 + * we got enumerated and allowed to draw a particular amount of current
  94 + */
  95 +
  96 +static void pcf50633_work_usbcurlim(struct work_struct *work)
  97 +{
  98 +       struct pcf50633_data *pcf =
  99 +                   container_of(work, struct pcf50633_data, work_usb_curlimit);
 100 +
 101 +       mutex_lock(&pcf->working_lock_usb_curlimit);
 102 +
 103 +       dev_info(&pcf->client.dev, "pcf50633_work_usbcurlim\n");
 104 +
 105 +       if (!pcf->probe_completed)
 106 +               goto reschedule;
 107 +
 108 +       /* we got a notification from USB stack before we completed resume...
 109 +        * that can only make trouble, reschedule for a retry
 110 +        */
 111 +       if (pcf->have_been_suspended && (pcf->have_been_suspended < 3))
 112 +               goto reschedule;
 113 +
 114 +       /*
 115 +        * did he pull USB before we managed to set the limit?
 116 +        */
 117 +       if (pcf->usb_removal_count_usb_curlimit != pcf->usb_removal_count)
 118 +               goto bail;
 119 +
 120 +       /* OK let's set the requested limit and finish */
 121 +
 122 +       dev_info(&pcf->client.dev, "pcf50633_work_usbcurlim setting %dmA\n",
 123 +                                                        pcf->pending_curlimit);
 124 +       pcf50633_usb_curlim_set(pcf, pcf->pending_curlimit);
 125 +
 126 +bail:
 127 +       mutex_unlock(&pcf->working_lock_usb_curlimit);
 128 +       return;
 129 +
 130 +reschedule:
 131 +       dev_info(&pcf->client.dev, "pcf50633_work_usbcurlim rescheduling\n");
 132 +       if (!schedule_work(&pcf->work_usb_curlimit))
 133 +               dev_err(&pcf->client.dev, "work item may be lost\n");
 134 +
 135 +       mutex_unlock(&pcf->working_lock_usb_curlimit);
 136 +       /* don't spew, delaying whatever else is happening */
 137 +       msleep(1);
 138 +}
 139 +
 140 +
 141 +/* this is an export to allow machine to set USB current limit according to
 142 + * notifications of USB stack about enumeration state.  We spawn a work
 143 + * function to handle the actual setting, because suspend / resume and such
 144 + * can be in a bad state since this gets called externally asychronous to
 145 + * anything else going on in pcf50633.
 146 + */
 147 +
 148 +int pcf50633_notify_usb_current_limit_change(struct pcf50633_data *pcf,
 149 +                                                               unsigned int ma)
 150 +{
 151 +       /* can happen if he calls with pcf50633_global before probe
 152 +        * have to bail with error since we can't even schedule the work
 153 +        */
 154 +       if (!pcf) {
 155 +               dev_err(&pcf->client.dev,
 156 +                       "pcf50633_notify_usb_current_limit_change "
 157 +                       "called with NULL pcf\n");
 158 +               return -EBUSY;
 159 +       }
 160 +
 161 +       dev_info(&pcf->client.dev,
 162 +                "pcf50633_notify_usb_current_limit_change %dmA\n", ma);
 163 +
 164 +       /* prepare to detect USB power removal before we complete */
 165 +       pcf->usb_removal_count_usb_curlimit = pcf->usb_removal_count;
 166 +
 167 +       pcf->pending_curlimit = ma;
 168 +
 169 +       if (!schedule_work(&pcf->work_usb_curlimit))
 170 +               dev_err(&pcf->client.dev, "work item may be lost\n");
 171 +
 172 +       return 0;
 173 +}
 174 +EXPORT_SYMBOL_GPL(pcf50633_notify_usb_current_limit_change);
 175 +
 176 +
 177  /* we are run when we see a NOBAT situation, because there is no interrupt
 178   * source in pcf50633 that triggers on resuming charging.  It watches to see
 179   * if charging resumes, it reassesses the charging source if it does.  If the
 180 @@ -1960,8 +2053,10 @@ static int pcf50633_detect(struct i2c_adapter *adapter, int address, int kind)
 181         mutex_init(&data->lock);
 182         mutex_init(&data->working_lock);
 183         mutex_init(&data->working_lock_nobat);
 184 +       mutex_init(&data->working_lock_usb_curlimit);
 185         INIT_WORK(&data->work, pcf50633_work);
 186         INIT_WORK(&data->work_nobat, pcf50633_work_nobat);
 187 +       INIT_WORK(&data->work_usb_curlimit, pcf50633_work_usbcurlim);
 188         data->irq = irq;
 189         data->working = 0;
 190         data->onkey_seconds = -1;
 191 @@ -2060,6 +2155,7 @@ static int pcf50633_detect(struct i2c_adapter *adapter, int address, int kind)
 192         }
 193
 194         apm_get_power_status = pcf50633_get_power_status;
 195 +       data->probe_completed = 1;
 196
 197  #ifdef CONFIG_MACH_NEO1973_GTA02
 198         if (machine_is_neo1973_gta02()) {
 199 diff --git a/include/linux/pcf50633.h b/include/linux/pcf50633.h
 200 index 0522d92..fa1c7e8 100644
 201 --- a/include/linux/pcf50633.h
 202 +++ b/include/linux/pcf50633.h
 203 @@ -129,6 +129,11 @@ extern void
 204  pcf50633_register_resume_dependency(struct pcf50633_data *pcf,
 205                                         struct resume_dependency *dep);
 206
 207 +extern int
 208 +pcf50633_notify_usb_current_limit_change(struct pcf50633_data *pcf,
 209 +                                                              unsigned int ma);
 210 +
 211 +
 212  /* 0 = initialized and resumed and ready to roll, !=0 = either not
 213   * initialized or not resumed yet
 214   */
 215 --
 216 1.5.6.3
 217