tegra kbc: Fixing android boot if key is kept press during boot.

Following changes are done:
- Created the new workqueue for the kbc scan process. On default workqueue,
  the msleep() was not causing the schedule() to booting process.
- If there is no entry in fifo then wait for the next scan to complete before
  re-reading the number of entries in the fifo. if there is no entry then rep
  key released.
- Fixed timing calculation and size of the event entry array.
- Fixed the debaunce count calculation from debaunce time from odm.

Tested on whistler, with normal boot as well as with continous key pressed d
the entire boot time.

Change-Id: I53b321ae6f5e1f425b51edcd63f7de4ae404e505
Reviewed-on: http://git-master/r/1238
Reviewed-by: Hu He <hhe@nvidia.com>
Tested-by: Hu He <hhe@nvidia.com>
Reviewed-by: Gary King <gking@nvidia.com>

3 files changed, 45 insertions, 22 deletions

diff --git a/arch/arm/mach-tegra/board_nvodm.c b/arch/arm/mach-tegra/board_nvodm.c
index d9eefc00db3f..f13f503a3683 100644
--- a/arch/arm/mach-tegra/board_nvodm.c
+++ b/arch/arm/mach-tegra/board_nvodm.c
@@ -430,7 +430,7 @@ static void kbc_init(void)
     struct tegra_kbc_plat *pdata = NULL;
     static struct resource res[2];
 
-    dev = platform_device_alloc("tegra_kbc", -1);
+    dev = platform_device_alloc("tegra-kbc", -1);
     if (!dev)
         goto fail;
 
diff --git a/arch/arm/mach-tegra/odm_to_plat.c b/arch/arm/mach-tegra/odm_to_plat.c
index 7ccc982d1f25..209268572276 100644
--- a/arch/arm/mach-tegra/odm_to_plat.c
+++ b/arch/arm/mach-tegra/odm_to_plat.c
@@ -71,12 +71,14 @@ struct tegra_kbc_plat *tegra_kbc_odm_to_plat(void)
 
 	NvOdmKbcGetParameter(NvOdmKbcParameter_DebounceTime, 1, &temp);
 
-	pdata->debounce_cnt = temp;
+	/* debounce time is reported from ODM in milliseconds,
+	 * but needs to be specified in 32KHz ticks */
+	pdata->debounce_cnt = temp *32;
 
 	/* repeat cycle is reported from ODM in milliseconds,
 	 * but needs to be specified in 32KHz ticks */
 	NvOdmKbcGetParameter(NvOdmKbcParameter_RepeatCycleTime, 1, &temp);
-	pdata->repeat_cnt = temp * 4096 / 125;
+	pdata->repeat_cnt = temp * 32;
 
 	temp = NvOdmPeripheralEnumerate(&srch_attr, &srch_val, 1, &guid, 1);
 	if (!temp) {
diff --git a/drivers/input/keyboard/tegra-kbc.c b/drivers/input/keyboard/tegra-kbc.c
index 1a5768fb602f..efd584dcd125 100644
--- a/drivers/input/keyboard/tegra-kbc.c
+++ b/drivers/input/keyboard/tegra-kbc.c
@@ -59,6 +59,7 @@ struct tegra_kbc {
 	unsigned int repoll_time;
 	struct tegra_kbc_plat *pdata;
 	struct work_struct key_repeat;
+	struct workqueue_struct *kbc_work_queue;
 #ifdef RM_SUPPORT
 	NvU32 client_id;
 #else
@@ -208,7 +209,7 @@ static int tegra_kbc_resume(struct platform_device *pdev)
 static void tegra_kbc_report_keys(struct tegra_kbc *kbc, int *fifo)
 {
 	int curr_fifo[KBC_MAX_KPENT];
-	u32 kp_ent_val[(KBC_MAX_KPENT*8 + 3) / 4];
+	u32 kp_ent_val[(KBC_MAX_KPENT + 3) / 4];
 	u32 *kp_ents = kp_ent_val;
 	u32 kp_ent;
 	unsigned long flags;
@@ -273,13 +274,13 @@ static void tegra_kbc_key_repeat(struct work_struct *work)
 		if (!val) {
 			/* release any pressed keys and exit the loop */
 			for (i=0; i<ARRAY_SIZE(fifo); i++) {
-				if (fifo[i]==-1) continue;
+				if (fifo[i] == -1)
+					continue;
 				input_report_key(kbc->idev, fifo[i], 0);
 			}
 			break;
 		}
 		tegra_kbc_report_keys(kbc, fifo);
-		/* FIXME: why is this here? */
 		msleep((val==1) ? kbc->repoll_time : 1);
 	}
 
@@ -296,6 +297,7 @@ static void tegra_kbc_close(struct input_dev *dev)
 	unsigned long flags;
 	u32 val;
 
+	spin_lock_irqsave(&kbc->lock, flags);
 	val = readl(kbc->mmio + KBC_CONTROL_0);
 	val &= ~1;
 	writel(val, kbc->mmio + KBC_CONTROL_0);
@@ -373,18 +375,6 @@ static int tegra_kbc_open(struct input_dev *dev)
 	tegra_kbc_config_pins(kbc);
 	tegra_kbc_setup_wakekeys(kbc, false);
 
-	/* atomically clear out any remaining entries in the key FIFO
-	 * and enable keyboard interrupts */
-	spin_lock_irqsave(&kbc->lock, flags);
-	val = readl(kbc->mmio + KBC_INT_0);
-	val >>= 4;
-	if (val) {
-		val = readl(kbc->mmio + KBC_KP_ENT0_0);
-		val = readl(kbc->mmio + KBC_KP_ENT1_0);
-	}
-	writel(0x7, kbc->mmio + KBC_INT_0);
-	spin_unlock_irqrestore(&kbc->lock, flags);
-
 	writel(kbc->pdata->repeat_cnt, kbc->mmio + KBC_RPT_DLY_0);
 
 	val = kbc->pdata->debounce_cnt << 4;
@@ -393,6 +383,22 @@ static int tegra_kbc_open(struct input_dev *dev)
 	val |= 1;     /* enable */
 	writel(val, kbc->mmio + KBC_CONTROL_0);
 
+	/* atomically clear out any remaining entries in the key FIFO
+	 * and enable keyboard interrupts */
+	spin_lock_irqsave(&kbc->lock, flags);
+	while(1) {
+		val = readl(kbc->mmio + KBC_INT_0);
+		val >>= 4;
+		if (val) {
+			val = readl(kbc->mmio + KBC_KP_ENT0_0);
+			val = readl(kbc->mmio + KBC_KP_ENT1_0);
+		} else {
+			break;
+		}
+	}
+	writel(0x7, kbc->mmio + KBC_INT_0);
+	spin_unlock_irqrestore(&kbc->lock, flags);
+
 	return 0;
 }
 
@@ -410,6 +416,7 @@ static int __devexit tegra_kbc_remove(struct platform_device *pdev)
 	input_unregister_device(kbc->idev);
 	input_free_device(kbc->idev);
 	iounmap(kbc->mmio);
+	destroy_workqueue(kbc->kbc_work_queue);
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	release_mem_region(res->start, res_size(res));
 
@@ -438,8 +445,7 @@ static irqreturn_t tegra_kbc_isr(int irq, void *args)
 		writel(ctl, kbc->mmio + KBC_CONTROL_0);
 		return IRQ_HANDLED;
 	}
-
-	schedule_work(&kbc->key_repeat);
+	queue_work(kbc->kbc_work_queue, &kbc->key_repeat);
 	return IRQ_HANDLED;
 }
 
@@ -454,6 +460,7 @@ static int __init tegra_kbc_probe(struct platform_device *pdev)
 	int cols[KBC_MAX_COL];
 	int i, j;
 	int nr = 0;
+	char name[64];
 
 	if (!pdata) return -EINVAL;
 
@@ -534,8 +541,10 @@ static int __init tegra_kbc_probe(struct platform_device *pdev)
 		}
 	}
 
+	/* The debaunce count is maximum 0x3FF clocks i.e. 10 bit configuration */
+	pdata->debounce_cnt = (pdata->debounce_cnt > 0x3FF)?0x3FF:pdata->debounce_cnt;
 	kbc->repoll_time = 5 + (16+pdata->debounce_cnt)*nr + pdata->repeat_cnt;
-	kbc->repoll_time = (kbc->repoll_time*1000 + 16384) / 32768;
+	kbc->repoll_time = (kbc->repoll_time + 31) / 32;
 
 	kbc->idev->evbit[0] = BIT_MASK(EV_KEY);
 
@@ -550,9 +559,20 @@ static int __init tegra_kbc_probe(struct platform_device *pdev)
 		}
 	}
 
+
+	/* create the workqueue for the kbc path */
+	snprintf(name, sizeof(name), "tegra-kbc");
+	kbc->kbc_work_queue = create_singlethread_workqueue(name);
+	if (kbc->kbc_work_queue == NULL) {
+		dev_err(&pdev->dev, "Failed to create work queue\n");
+		err = -ENODEV;
+		goto fail;
+	}
+
 	/* keycode FIFO needs to be read atomically; leave local
 	 * interrupts disabled when handling KBC interrupt */
 	INIT_WORK(&kbc->key_repeat, tegra_kbc_key_repeat);
+
 	err = request_irq(irq, tegra_kbc_isr, IRQF_DISABLED, pdev->name, kbc);
 	if (err) {
 		dev_err(&pdev->dev, "failed to request keypad IRQ\n");
@@ -574,6 +594,7 @@ fail:
 	if (kbc->idev) input_free_device(kbc->idev);
 	free_resource(kbc);
 	if (kbc->mmio) iounmap(kbc->mmio);
+	if (kbc->kbc_work_queue) destroy_workqueue(kbc->kbc_work_queue);
 	kfree(kbc);
 	return err;
 }
@@ -586,7 +607,7 @@ static struct platform_driver tegra_kbc_driver = {
 	.resume		= tegra_kbc_resume,
 #endif
 	.driver	= {
-		.name	= "tegra_kbc"
+		.name	= "tegra-kbc"
 	}
 };