target/linux/s3c24xx/patches-2.6.26/1176-fix-pcf50633-suspend-state-as-enum.patch.patch

   1 From 591a5d7e8da059de812d315b865fd5c0fa89071e Mon Sep 17 00:00:00 2001
   2 From: Andy Green <andy@openmoko.com>
   3 Date: Fri, 25 Jul 2008 23:06:15 +0100
   4 Subject: [PATCH] fix-pcf50633-suspend-state-as-enum.patch
   5
   6 Use an enum to define pcf50633 suspend / resume state.
   7 Add PCF50633_SS_RESUMING_BUT_NOT_US_YET to be the state
   8 early in resume: add platform driver resume function just
   9 to set this state so we can differentiate between early
  10 resume and late suspend.
  11
  12 Signed-off-by: Andy Green <andy@openmoko.com>
  13 ---
  14  drivers/i2c/chips/pcf50633.c |   73 ++++++++++++++++++++++++++++++++++--------
  15  1 files changed, 59 insertions(+), 14 deletions(-)
  16
  17 diff --git a/drivers/i2c/chips/pcf50633.c b/drivers/i2c/chips/pcf50633.c
  18 index 37dfca6..87a3003 100644
  19 --- a/drivers/i2c/chips/pcf50633.c
  20 +++ b/drivers/i2c/chips/pcf50633.c
  21 @@ -108,6 +108,16 @@ enum charger_type {
  22
  23  #define MAX_ADC_FIFO_DEPTH 8
  24
  25 +enum pcf50633_suspend_states {
  26 +       PCF50633_SS_RUNNING,
  27 +       PCF50633_SS_STARTING_SUSPEND,
  28 +       PCF50633_SS_COMPLETED_SUSPEND,
  29 +       PCF50633_SS_RESUMING_BUT_NOT_US_YET,
  30 +       PCF50633_SS_STARTING_RESUME,
  31 +       PCF50633_SS_COMPLETED_RESUME,
  32 +};
  33 +
  34 +
  35  struct pcf50633_data {
  36         struct i2c_client client;
  37         struct pcf50633_platform_data *pdata;
  38 @@ -122,9 +132,9 @@ struct pcf50633_data {
  39         int allow_close;
  40         int onkey_seconds;
  41         int irq;
  42 -       int have_been_suspended;
  43 +       enum pcf50633_suspend_states suspend_state;
  44         int usb_removal_count;
  45 -       unsigned char pcfirq_resume[5];
  46 +       u8 pcfirq_resume[5];
  47         int probe_completed;
  48
  49         /* if he pulls battery while charging, we notice that and correctly
  50 @@ -191,7 +201,7 @@ static struct platform_device *pcf50633_pdev;
  51
  52  static int __reg_write(struct pcf50633_data *pcf, u_int8_t reg, u_int8_t val)
  53  {
  54 -       if (pcf->have_been_suspended == 1) {
  55 +       if (pcf->suspend_state == PCF50633_SS_COMPLETED_SUSPEND) {
  56                 dev_err(&pcf->client.dev, "__reg_write while suspended\n");
  57                 dump_stack();
  58         }
  59 @@ -213,7 +223,7 @@ static int32_t __reg_read(struct pcf50633_data *pcf, u_int8_t reg)
  60  {
  61         int32_t ret;
  62
  63 -       if (pcf->have_been_suspended == 1) {
  64 +       if (pcf->suspend_state == PCF50633_SS_COMPLETED_SUSPEND) {
  65                 dev_err(&pcf->client.dev, "__reg_read while suspended\n");
  66                 dump_stack();
  67         }
  68 @@ -630,7 +640,8 @@ static void pcf50633_work_usbcurlim(struct work_struct *work)
  69         /* we got a notification from USB stack before we completed resume...
  70          * that can only make trouble, reschedule for a retry
  71          */
  72 -       if (pcf->have_been_suspended && (pcf->have_been_suspended < 3))
  73 +       if (pcf->suspend_state &&
  74 +                    (pcf->suspend_state < PCF50633_SS_COMPLETED_RESUME))
  75                 goto reschedule;
  76
  77         /*
  78 @@ -751,6 +762,21 @@ static void pcf50633_work(struct work_struct *work)
  79         pcf->working = 1;
  80
  81         /*
  82 +        * if we are presently suspending, we are not in a position to deal
  83 +        * with pcf50633 interrupts at all.
  84 +        *
  85 +        * Because we didn't clear the int pending registers, there will be
  86 +        * no edge / interrupt waiting for us when we wake.  But it is OK
  87 +        * because at the end of our resume, we call this workqueue function
  88 +        * gratuitously, clearing the pending register and re-enabling
  89 +        * servicing this interrupt.
  90 +        */
  91 +
  92 +       if ((pcf->suspend_state == PCF50633_SS_STARTING_SUSPEND) ||
  93 +           (pcf->suspend_state == PCF50633_SS_COMPLETED_SUSPEND))
  94 +               goto bail;
  95 +
  96 +       /*
  97          * If we are inside suspend -> resume completion time we don't attempt
  98          * service until we have fully resumed.  Although we could talk to the
  99          * device as soon as I2C is up, the regs in the device which we might
 100 @@ -1154,8 +1180,9 @@ reschedule:
 101         /* EXCEPTION: if we are in the middle of suspending, we don't have
 102          * time to hang around since we may be turned off core 1V3 already
 103          */
 104 -       if (pcf->have_been_suspended != 1) {
 105 -               msleep(50);
 106 +       if ((pcf->suspend_state != PCF50633_SS_STARTING_SUSPEND) &&
 107 +           (pcf->suspend_state != PCF50633_SS_COMPLETED_SUSPEND)) {
 108 +               msleep(10);
 109                 dev_info(&pcf->client.dev, "rescheduling interrupt service\n");
 110         }
 111         if (!schedule_work(&pcf->work))
 112 @@ -2315,8 +2342,9 @@ static int pcf50633_suspend(struct device *dev, pm_message_t state)
 113
 114         /* we suspend once (!) as late as possible in the suspend sequencing */
 115
 116 -       if ((state.event != PM_EVENT_SUSPEND) || (pcf->have_been_suspended))
 117 -               return 0;
 118 +       if ((state.event != PM_EVENT_SUSPEND) ||
 119 +           (pcf->suspend_state != PCF50633_SS_RUNNING))
 120 +               return -EBUSY;
 121
 122         /* The general idea is to power down all unused power supplies,
 123          * and then mask all PCF50633 interrupt sources but EXTONR, ONKEYF
 124 @@ -2380,7 +2408,7 @@ static int pcf50633_suspend(struct device *dev, pm_message_t state)
 125         if (ret)
 126                 dev_err(dev, "Failed to set wake masks :-( %d\n", ret);
 127
 128 -       pcf->have_been_suspended = 1;
 129 +       pcf->suspend_state = PCF50633_SS_COMPLETED_SUSPEND;
 130
 131         mutex_unlock(&pcf->lock);
 132
 133 @@ -2393,7 +2421,8 @@ int pcf50633_ready(struct pcf50633_data *pcf)
 134         if (!pcf)
 135                 return -EACCES;
 136
 137 -       if (pcf->have_been_suspended && (pcf->have_been_suspended < 3))
 138 +       if ((pcf->suspend_state != PCF50633_SS_RUNNING) &&
 139 +           (pcf->suspend_state < PCF50633_SS_COMPLETED_RESUME))
 140                 return -EBUSY;
 141
 142         return 0;
 143 @@ -2428,10 +2457,10 @@ static int pcf50633_resume(struct device *dev)
 144         u8 res[5];
 145
 146         dev_info(dev, "pcf50633_resume suspended on entry = %d\n",
 147 -                                                     pcf->have_been_suspended);
 148 +                                                (int)pcf->suspend_state);
 149         mutex_lock(&pcf->lock);
 150
 151 -       pcf->have_been_suspended = 2; /* resuming */
 152 +       pcf->suspend_state = PCF50633_SS_STARTING_RESUME;
 153
 154         /* these guys get reset while pcf50633 is suspend state, refresh */
 155
 156 @@ -2464,7 +2493,7 @@ static int pcf50633_resume(struct device *dev)
 157         if (ret)
 158                 dev_err(dev, "Failed to set int masks :-( %d\n", ret);
 159
 160 -       pcf->have_been_suspended = 3; /* resume completed */
 161 +       pcf->suspend_state = PCF50633_SS_COMPLETED_RESUME;
 162
 163         mutex_unlock(&pcf->lock);
 164
 165 @@ -2498,6 +2527,21 @@ static struct i2c_driver pcf50633_driver = {
 166         .detach_client  = pcf50633_detach_client,
 167  };
 168
 169 +/* we have this purely to capture an early indication that we are coming out
 170 + * of suspend, before our device resume got called; async interrupt service is
 171 + * interested in this
 172 + */
 173 +
 174 +static int pcf50633_plat_resume(struct platform_device *pdev)
 175 +{
 176 +       /* i2c_get_clientdata(to_i2c_client(&pdev->dev)) returns NULL at this
 177 +        * early resume time so we have to use pcf50633_global
 178 +        */
 179 +       pcf50633_global->suspend_state = PCF50633_SS_RESUMING_BUT_NOT_US_YET;
 180 +
 181 +       return 0;
 182 +}
 183 +
 184  /* platform driver, since i2c devices don't have platform_data */
 185  static int __init pcf50633_plat_probe(struct platform_device *pdev)
 186  {
 187 @@ -2519,6 +2563,7 @@ static int pcf50633_plat_remove(struct platform_device *pdev)
 188  static struct platform_driver pcf50633_plat_driver = {
 189         .probe  = pcf50633_plat_probe,
 190         .remove = pcf50633_plat_remove,
 191 +       .resume_early = pcf50633_plat_resume,
 192         .driver = {
 193                 .owner  = THIS_MODULE,
 194                 .name   = "pcf50633",
 195 --
 196 1.5.6.3
 197