[PATCH 3.16 097/134] power: supply: pda_power: move from timer to delayed_work

From: Ben Hutchings
Date: Fri Aug 18 2017 - 09:30:29 EST


3.16.47-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Michael Trimarchi <michael@xxxxxxxxxxxxxxxxxxxx>

commit 633e8799ddc09431be2744c4a1efdbda13af2b0b upstream.

This changed is needed to avoid locking problem during
boot as shown:

<5>[ 8.824096] Registering SWP/SWPB emulation handler
<6>[ 8.977294] clock: disabling unused clocks to save power
<3>[ 9.108154] BUG: sleeping function called from invalid context at kernel_albert/kernel/mutex.c:269
<3>[ 9.122894] in_atomic(): 1, irqs_disabled(): 0, pid: 1, name: swapper/0
<4>[ 9.130249] 3 locks held by swapper/0/1:
<4>[ 9.134613] #0: (&__lockdep_no_validate__){......}, at: [<c0342430>] __driver_attach+0x58/0xa8
<4>[ 9.144500] #1: (&__lockdep_no_validate__){......}, at: [<c0342440>] __driver_attach+0x68/0xa8
<4>[ 9.154357] #2: (&polling_timer){......}, at: [<c0053770>] run_timer_softirq+0x108/0x3ec
<4>[ 9.163726] Backtrace:
<4>[ 9.166473] [<c001269c>] (dump_backtrace+0x0/0x114) from [<c067e5f0>] (dump_stack+0x20/0x24)
<4>[ 9.175811] r6:00203230 r5:0000010d r4:d782e000 r3:60000113
<4>[ 9.182250] [<c067e5d0>] (dump_stack+0x0/0x24) from [<c007441c>] (__might_sleep+0x10c/0x128)
<4>[ 9.191650] [<c0074310>] (__might_sleep+0x0/0x128) from [<c0688f60>] (mutex_lock_nested+0x34/0x36c)
<4>[ 9.201660] r5:c02d5350 r4:d79a0c64
<4>[ 9.205688] [<c0688f2c>] (mutex_lock_nested+0x0/0x36c) from [<c02d5350>] (regulator_set_current_limit+0x30/0x118)
<4>[ 9.217071] [<c02d5320>] (regulator_set_current_limit+0x0/0x118) from [<c0435ce0>] (update_charger+0x84/0xc4)
<4>[ 9.228027] r7:d782fb20 r6:00000101 r5:c1767e94 r4:00000000
<4>[ 9.234436] [<c0435c5c>] (update_charger+0x0/0xc4) from [<c0435d40>] (psy_changed+0x20/0x48)
<4>[ 9.243804] r5:d782e000 r4:c1767e94
<4>[ 9.247802] [<c0435d20>] (psy_changed+0x0/0x48) from [<c0435dec>] (polling_timer_func+0x84/0xb8)
<4>[ 9.257537] r4:c1767e94 r3:00000002
<4>[ 9.261566] [<c0435d68>] (polling_timer_func+0x0/0xb8) from [<c00537e4>] (run_timer_softirq+0x17c/0x3ec)
<4>[ 9.272033] r4:c1767eb0 r3:00000000
<4>[ 9.276062] [<c0053668>] (run_timer_softirq+0x0/0x3ec) from [<c004b000>] (__do_softirq+0xf0/0x298)
<4>[ 9.286010] [<c004af10>] (__do_softirq+0x0/0x298) from [<c004b650>] (irq_exit+0x98/0xa0)
<4>[ 9.295013] [<c004b5b8>] (irq_exit+0x0/0xa0) from [<c000edbc>] (handle_IRQ+0x60/0xc0)
<4>[ 9.303680] r4:c1194e98 r3:c00bc778
<4>[ 9.307708] [<c000ed5c>] (handle_IRQ+0x0/0xc0) from [<c0008504>] (gic_handle_irq+0x34/0x68)
<4>[ 9.316955] r8:000ac383 r7:d782fc3c r6:d782fc08 r5:c11936c4 r4:e0802100
<4>[ 9.324310] r3:c026ba48
<4>[ 9.327301] [<c00084d0>] (gic_handle_irq+0x0/0x68) from [<c068c2c0>] (__irq_svc+0x40/0x74)
<4>[ 9.336456] Exception stack(0xd782fc08 to 0xd782fc50)
<4>[ 9.342041] fc00: d6e30e6c ac383627 00000000 ac383417 ea19c000 ea200000
<4>[ 9.351104] fc20: beffffff 00000667 000ac383 d6e30670 d6e3066c d782fc94 d782fbe8 d782fc50
<4>[ 9.360168] fc40: c026ba48 c001d1f0 00000113 ffffffff

Fixes: b2998049cfae ("[BATTERY] pda_power platform driver")
Signed-off-by: Michael Trimarchi <michael@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Anthony Brandon <anthony@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxxxx>
[bwh: Backported to 3.16: adjust filename]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/power/pda_power.c | 49 ++++++++++++++++++++++------------------
1 file changed, 27 insertions(+), 22 deletions(-)

--- a/drivers/power/pda_power.c
+++ b/drivers/power/pda_power.c
@@ -30,9 +30,9 @@ static inline unsigned int get_irq_flags
static struct device *dev;
static struct pda_power_pdata *pdata;
static struct resource *ac_irq, *usb_irq;
-static struct timer_list charger_timer;
-static struct timer_list supply_timer;
-static struct timer_list polling_timer;
+static struct delayed_work charger_work;
+static struct delayed_work polling_work;
+static struct delayed_work supply_work;
static int polling;

#if IS_ENABLED(CONFIG_USB_PHY)
@@ -143,7 +143,7 @@ static void update_charger(void)
}
}

-static void supply_timer_func(unsigned long unused)
+static void supply_work_func(struct work_struct *work)
{
if (ac_status == PDA_PSY_TO_CHANGE) {
ac_status = new_ac_status;
@@ -164,11 +164,12 @@ static void psy_changed(void)
* Okay, charger set. Now wait a bit before notifying supplicants,
* charge power should stabilize.
*/
- mod_timer(&supply_timer,
- jiffies + msecs_to_jiffies(pdata->wait_for_charger));
+ cancel_delayed_work(&supply_work);
+ schedule_delayed_work(&supply_work,
+ msecs_to_jiffies(pdata->wait_for_charger));
}

-static void charger_timer_func(unsigned long unused)
+static void charger_work_func(struct work_struct *work)
{
update_status();
psy_changed();
@@ -187,13 +188,14 @@ static irqreturn_t power_changed_isr(int
* Wait a bit before reading ac/usb line status and setting charger,
* because ac/usb status readings may lag from irq.
*/
- mod_timer(&charger_timer,
- jiffies + msecs_to_jiffies(pdata->wait_for_status));
+ cancel_delayed_work(&charger_work);
+ schedule_delayed_work(&charger_work,
+ msecs_to_jiffies(pdata->wait_for_status));

return IRQ_HANDLED;
}

-static void polling_timer_func(unsigned long unused)
+static void polling_work_func(struct work_struct *work)
{
int changed = 0;

@@ -214,8 +216,9 @@ static void polling_timer_func(unsigned
if (changed)
psy_changed();

- mod_timer(&polling_timer,
- jiffies + msecs_to_jiffies(pdata->polling_interval));
+ cancel_delayed_work(&polling_work);
+ schedule_delayed_work(&polling_work,
+ msecs_to_jiffies(pdata->polling_interval));
}

#if IS_ENABLED(CONFIG_USB_PHY)
@@ -253,8 +256,9 @@ static int otg_handle_notification(struc
* Wait a bit before reading ac/usb line status and setting charger,
* because ac/usb status readings may lag from irq.
*/
- mod_timer(&charger_timer,
- jiffies + msecs_to_jiffies(pdata->wait_for_status));
+ cancel_delayed_work(&charger_work);
+ schedule_delayed_work(&charger_work,
+ msecs_to_jiffies(pdata->wait_for_status));

return NOTIFY_OK;
}
@@ -302,8 +306,8 @@ static int pda_power_probe(struct platfo
if (!pdata->ac_max_uA)
pdata->ac_max_uA = 500000;

- setup_timer(&charger_timer, charger_timer_func, 0);
- setup_timer(&supply_timer, supply_timer_func, 0);
+ INIT_DELAYED_WORK(&charger_work, charger_work_func);
+ INIT_DELAYED_WORK(&supply_work, supply_work_func);

ac_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "ac");
usb_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "usb");
@@ -381,9 +385,10 @@ static int pda_power_probe(struct platfo

if (polling) {
dev_dbg(dev, "will poll for status\n");
- setup_timer(&polling_timer, polling_timer_func, 0);
- mod_timer(&polling_timer,
- jiffies + msecs_to_jiffies(pdata->polling_interval));
+ INIT_DELAYED_WORK(&polling_work, polling_work_func);
+ cancel_delayed_work(&polling_work);
+ schedule_delayed_work(&polling_work,
+ msecs_to_jiffies(pdata->polling_interval));
}

if (ac_irq || usb_irq)
@@ -429,9 +434,9 @@ static int pda_power_remove(struct platf
free_irq(ac_irq->start, &pda_psy_ac);

if (polling)
- del_timer_sync(&polling_timer);
- del_timer_sync(&charger_timer);
- del_timer_sync(&supply_timer);
+ cancel_delayed_work_sync(&polling_work);
+ cancel_delayed_work_sync(&charger_work);
+ cancel_delayed_work_sync(&supply_work);

if (pdata->is_usb_online)
power_supply_unregister(&pda_psy_usb);