greybus: arche-platform: Rework platform/wd-line state transition logic

This patch simplifies and improves the readability of the internal state
transition logic of arche platform driver state transition logic by:

1. Making a dedicated function to state-transition the platform code.
2. Condense the decision to swtich states down to a single switch
   statement instead of four separate if/else clauses.

Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Suggested-by: Alex Elder <elder@linaro.org>
Reviewed-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
This commit is contained in:
Bryan O'Donoghue 2016-05-05 15:34:59 +01:00 committed by Greg Kroah-Hartman
parent 886aba558b
commit c4058b7926

View file

@ -63,6 +63,13 @@ struct arche_platform_drvdata {
struct device *dev;
};
/* Requires calling context to hold arche_pdata->spinlock */
static void arche_platform_set_state(struct arche_platform_drvdata *arche_pdata,
enum arche_platform_state state)
{
arche_pdata->state = state;
}
/*
* arche_platform_change_state: Change the operational state
*
@ -122,22 +129,26 @@ int arche_platform_change_state(enum arche_platform_state state)
goto exit;
}
if (arche_pdata->state == ARCHE_PLATFORM_STATE_OFF ||
arche_pdata->state == ARCHE_PLATFORM_STATE_STANDBY ||
arche_pdata->state == ARCHE_PLATFORM_STATE_FW_FLASHING) {
switch (state) {
case ARCHE_PLATFORM_STATE_TIME_SYNC:
disable_irq(arche_pdata->wake_detect_irq);
break;
case ARCHE_PLATFORM_STATE_ACTIVE:
enable_irq(arche_pdata->wake_detect_irq);
break;
case ARCHE_PLATFORM_STATE_OFF:
case ARCHE_PLATFORM_STATE_STANDBY:
case ARCHE_PLATFORM_STATE_FW_FLASHING:
dev_err(arche_pdata->dev, "busy, request to retry later\n");
goto exit;
default:
ret = -EINVAL;
dev_err(arche_pdata->dev,
"invalid state transition request\n");
goto exit;
}
if (state == ARCHE_PLATFORM_STATE_TIME_SYNC) {
disable_irq(arche_pdata->wake_detect_irq);
arche_pdata->state = ARCHE_PLATFORM_STATE_TIME_SYNC;
} else if (state == ARCHE_PLATFORM_STATE_ACTIVE) {
arche_pdata->state = ARCHE_PLATFORM_STATE_ACTIVE;
enable_irq(arche_pdata->wake_detect_irq);
} else {
dev_err(arche_pdata->dev, "invalid state transition request\n");
}
arche_platform_set_state(arche_pdata, state);
ret = 0;
exit:
spin_unlock_irqrestore(&arche_pdata->wake_lock, flags);
mutex_unlock(&arche_pdata->platform_state_mutex);
@ -146,6 +157,14 @@ int arche_platform_change_state(enum arche_platform_state state)
}
EXPORT_SYMBOL_GPL(arche_platform_change_state);
/* Requires arche_pdata->wake_lock is held by calling context */
static void arche_platform_set_wake_detect_state(
struct arche_platform_drvdata *arche_pdata,
enum svc_wakedetect_state state)
{
arche_pdata->wake_detect_state = state;
}
static inline void svc_reset_onoff(unsigned int gpio, bool onoff)
{
gpio_set_value(gpio, onoff);
@ -208,7 +227,8 @@ static irqreturn_t arche_platform_wd_irq_thread(int irq, void *devid)
return IRQ_HANDLED;
}
arche_pdata->wake_detect_state = WD_STATE_COLDBOOT_START;
arche_platform_set_wake_detect_state(arche_pdata,
WD_STATE_COLDBOOT_START);
spin_unlock_irqrestore(&arche_pdata->wake_lock, flags);
/* It should complete power cycle, so first make sure it is poweroff */
@ -222,7 +242,7 @@ static irqreturn_t arche_platform_wd_irq_thread(int irq, void *devid)
dev_warn(arche_pdata->dev, "failed to control hub device\n");
spin_lock_irqsave(&arche_pdata->wake_lock, flags);
arche_pdata->wake_detect_state = WD_STATE_IDLE;
arche_platform_set_wake_detect_state(arche_pdata, WD_STATE_IDLE);
spin_unlock_irqrestore(&arche_pdata->wake_lock, flags);
return IRQ_HANDLED;
@ -247,13 +267,14 @@ static irqreturn_t arche_platform_wd_irq(int irq, void *devid)
if (time_before(jiffies,
arche_pdata->wake_detect_start +
msecs_to_jiffies(WD_COLDBOOT_PULSE_WIDTH_MS))) {
arche_pdata->wake_detect_state = WD_STATE_IDLE;
arche_platform_set_wake_detect_state(arche_pdata,
WD_STATE_IDLE);
} else {
/* Check we are not in middle of irq thread already */
if (arche_pdata->wake_detect_state !=
WD_STATE_COLDBOOT_START) {
arche_pdata->wake_detect_state =
WD_STATE_COLDBOOT_TRIG;
arche_platform_set_wake_detect_state(arche_pdata,
WD_STATE_COLDBOOT_TRIG);
spin_unlock_irqrestore(
&arche_pdata->wake_lock,
flags);
@ -270,7 +291,8 @@ static irqreturn_t arche_platform_wd_irq(int irq, void *devid)
* it is meant for coldboot and set the flag. If wake/detect line stays low
* beyond 30msec, then it is coldboot else fallback to standby boot.
*/
arche_pdata->wake_detect_state = WD_STATE_BOOT_INIT;
arche_platform_set_wake_detect_state(arche_pdata,
WD_STATE_BOOT_INIT);
}
}
@ -308,7 +330,7 @@ static int arche_platform_coldboot_seq(struct arche_platform_drvdata *arche_pdat
svc_reset_onoff(arche_pdata->svc_reset_gpio,
!arche_pdata->is_reset_act_hi);
arche_pdata->state = ARCHE_PLATFORM_STATE_ACTIVE;
arche_platform_set_state(arche_pdata, ARCHE_PLATFORM_STATE_ACTIVE);
return 0;
}
@ -332,7 +354,7 @@ static void arche_platform_fw_flashing_seq(struct arche_platform_drvdata *arche_
svc_reset_onoff(arche_pdata->svc_reset_gpio,
!arche_pdata->is_reset_act_hi);
arche_pdata->state = ARCHE_PLATFORM_STATE_FW_FLASHING;
arche_platform_set_state(arche_pdata, ARCHE_PLATFORM_STATE_FW_FLASHING);
}
@ -353,7 +375,8 @@ static void arche_platform_poweroff_seq(struct arche_platform_drvdata *arche_pda
gpio_direction_output(arche_pdata->wake_detect_gpio, 0);
usleep_range(100, 200);
spin_lock_irqsave(&arche_pdata->wake_lock, flags);
arche_pdata->wake_detect_state = WD_STATE_IDLE;
arche_platform_set_wake_detect_state(arche_pdata,
WD_STATE_IDLE);
spin_unlock_irqrestore(&arche_pdata->wake_lock, flags);
clk_disable_unprepare(arche_pdata->svc_ref_clk);
@ -363,7 +386,7 @@ static void arche_platform_poweroff_seq(struct arche_platform_drvdata *arche_pda
svc_reset_onoff(arche_pdata->svc_reset_gpio,
arche_pdata->is_reset_act_hi);
arche_pdata->state = ARCHE_PLATFORM_STATE_OFF;
arche_platform_set_state(arche_pdata, ARCHE_PLATFORM_STATE_OFF);
}
static ssize_t state_store(struct device *dev,
@ -502,7 +525,7 @@ static int arche_platform_probe(struct platform_device *pdev)
dev_err(dev, "failed to set svc-reset gpio dir:%d\n", ret);
return ret;
}
arche_pdata->state = ARCHE_PLATFORM_STATE_OFF;
arche_platform_set_state(arche_pdata, ARCHE_PLATFORM_STATE_OFF);
arche_pdata->svc_sysboot_gpio = of_get_named_gpio(np,
"svc,sysboot-gpio", 0);
@ -567,7 +590,7 @@ static int arche_platform_probe(struct platform_device *pdev)
}
/* deassert wake detect */
gpio_direction_output(arche_pdata->wake_detect_gpio, 0);
arche_pdata->wake_detect_state = WD_STATE_IDLE;
arche_platform_set_wake_detect_state(arche_pdata, WD_STATE_IDLE);
arche_pdata->dev = &pdev->dev;