[media] m5mols: Improve the interrupt handling routines

The work struct based interrupt handling is not flexible enough
as the M-5MOLS control sequence involves I2C access sequences
before and after an interrupt is generated. A single waitqueue is
enough for the job so remove the work struct based code.

Signed-off-by: HeungJun Kim <riverful.kim@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

3 files changed, 25 insertions, 74 deletions

diff --git a/drivers/media/video/m5mols/m5mols.h b/drivers/media/video/m5mols/m5mols.h
index f33171672c31..2829d4a95f6a 100644
--- a/drivers/media/video/m5mols/m5mols.h
+++ b/drivers/media/video/m5mols/m5mols.h
@@ -163,7 +163,6 @@ struct m5mols_version {
  * @ffmt: current fmt according to resolution type
  * @res_type: current resolution type
  * @irq_waitq: waitqueue for the capture
- * @work_irq: workqueue for the IRQ
  * @flags: state variable for the interrupt handler
  * @handle: control handler
  * @autoexposure: Auto Exposure control
@@ -180,7 +179,6 @@ struct m5mols_version {
  * @lock_ae: true means the Auto Exposure is locked
  * @lock_awb: true means the Aut WhiteBalance is locked
  * @resolution: register value for current resolution
- * @interrupt: register value for current interrupt status
  * @mode: register value for current operation mode
  * @mode_save: register value for current operation mode for saving
  * @set_power: optional power callback to the board code
@@ -192,8 +190,7 @@ struct m5mols_info {
         struct v4l2_mbus_framefmt ffmt[M5MOLS_RESTYPE_MAX];
         int res_type;
         wait_queue_head_t irq_waitq;
-        struct work_struct work_irq;
-        unsigned long flags;
+        atomic_t irq_done;
 
         struct v4l2_ctrl_handler handle;
         /* Autoexposure/exposure control cluster */
@@ -213,14 +210,11 @@ struct m5mols_info {
         bool lock_ae;
         bool lock_awb;
         u8 resolution;
-        u8 interrupt;
         u8 mode;
         u8 mode_save;
         int (*set_power)(struct device *dev, int on);
 };
 
-#define ST_CAPT_IRQ 0
-
 #define is_powered(__info) (__info->power)
 #define is_ctrl_synced(__info) (__info->ctrl_sync)
 #define is_available_af(__info) (__info->ver.af)
@@ -290,6 +284,7 @@ int m5mols_busy_wait(struct v4l2_subdev *sd, u32 reg, u32 value, u32 mask,
 int m5mols_mode(struct m5mols_info *info, u8 mode);
 
 int m5mols_enable_interrupt(struct v4l2_subdev *sd, u8 reg);
+int m5mols_wait_interrupt(struct v4l2_subdev *sd, u8 condition, u32 timeout);
 int m5mols_sync_controls(struct m5mols_info *info);
 int m5mols_start_capture(struct m5mols_info *info);
 int m5mols_do_scenemode(struct m5mols_info *info, u8 mode);
diff --git a/drivers/media/video/m5mols/m5mols_capture.c b/drivers/media/video/m5mols/m5mols_capture.c
index 3248ac805711..090e50afbc9f 100644
--- a/drivers/media/video/m5mols/m5mols_capture.c
+++ b/drivers/media/video/m5mols/m5mols_capture.c
@@ -29,22 +29,6 @@
 #include "m5mols.h"
 #include "m5mols_reg.h"
 
-static int m5mols_capture_error_handler(struct m5mols_info *info,
-                                        int timeout)
-{
-        int ret;
-
-        /* Disable all interrupts and clear relevant interrupt staus bits */
-        ret = m5mols_write(&info->sd, SYSTEM_INT_ENABLE,
-                           info->interrupt & ~(REG_INT_CAPTURE));
-        if (ret)
-                return ret;
-
-        if (timeout == 0)
-                return -ETIMEDOUT;
-
-        return 0;
-}
 /**
  * m5mols_read_rational - I2C read of a rational number
  *
@@ -121,7 +105,6 @@ int m5mols_start_capture(struct m5mols_info *info)
 {
         struct v4l2_subdev *sd = &info->sd;
         u8 resolution = info->resolution;
-        int timeout;
         int ret;
 
         /*
@@ -142,14 +125,9 @@ int m5mols_start_capture(struct m5mols_info *info)
                 ret = m5mols_enable_interrupt(sd, REG_INT_CAPTURE);
         if (!ret)
                 ret = m5mols_mode(info, REG_CAPTURE);
-        if (!ret) {
+        if (!ret)
                 /* Wait for capture interrupt, after changing capture mode */
-                timeout = wait_event_interruptible_timeout(info->irq_waitq,
-                                           test_bit(ST_CAPT_IRQ, &info->flags),
-                                           msecs_to_jiffies(2000));
-                if (test_and_clear_bit(ST_CAPT_IRQ, &info->flags))
-                        ret = m5mols_capture_error_handler(info, timeout);
-        }
+                ret = m5mols_wait_interrupt(sd, REG_INT_CAPTURE, 2000);
         if (!ret)
                 ret = m5mols_lock_3a(info, false);
         if (ret)
@@ -175,15 +153,13 @@ int m5mols_start_capture(struct m5mols_info *info)
                 ret = m5mols_write(sd, CAPC_START, REG_CAP_START_MAIN);
         if (!ret) {
                 /* Wait for the capture completion interrupt */
-                timeout = wait_event_interruptible_timeout(info->irq_waitq,
-                                           test_bit(ST_CAPT_IRQ, &info->flags),
-                                           msecs_to_jiffies(2000));
-                if (test_and_clear_bit(ST_CAPT_IRQ, &info->flags)) {
+                ret = m5mols_wait_interrupt(sd, REG_INT_CAPTURE, 2000);
+                if (!ret) {
                         ret = m5mols_capture_info(info);
                         if (!ret)
                                 v4l2_subdev_notify(sd, 0, &info->cap.total);
                 }
         }
 
-        return m5mols_capture_error_handler(info, timeout);
+        return ret;
 }
diff --git a/drivers/media/video/m5mols/m5mols_core.c b/drivers/media/video/m5mols/m5mols_core.c
index 5005127bb11c..68f117a413af 100644
--- a/drivers/media/video/m5mols/m5mols_core.c
+++ b/drivers/media/video/m5mols/m5mols_core.c
@@ -323,6 +323,20 @@ int m5mols_enable_interrupt(struct v4l2_subdev *sd, u8 reg)
         return ret;
 }
 
+int m5mols_wait_interrupt(struct v4l2_subdev *sd, u8 irq_mask, u32 timeout)
+{
+        struct m5mols_info *info = to_m5mols(sd);
+
+        int ret = wait_event_interruptible_timeout(info->irq_waitq,
+                                atomic_add_unless(&info->irq_done, -1, 0),
+                                msecs_to_jiffies(timeout));
+        if (ret <= 0)
+                return ret ? ret : -ETIMEDOUT;
+
+        return m5mols_busy_wait(sd, SYSTEM_INT_FACTOR, irq_mask,
+                                M5MOLS_I2C_RDY_WAIT_FL | irq_mask, -1);
+}
+
 /**
  * m5mols_reg_mode - Write the mode and check busy status
  *
@@ -889,46 +903,12 @@ static const struct v4l2_subdev_ops m5mols_ops = {
         .video          = &m5mols_video_ops,
 };
 
-static void m5mols_irq_work(struct work_struct *work)
-{
-        struct m5mols_info *info =
-                container_of(work, struct m5mols_info, work_irq);
-        struct v4l2_subdev *sd = &info->sd;
-        u8 reg;
-        int ret;
-
-        if (!is_powered(info) ||
-                        m5mols_read_u8(sd, SYSTEM_INT_FACTOR, &info->interrupt))
-                return;
-
-        switch (info->interrupt & REG_INT_MASK) {
-        case REG_INT_AF:
-                if (!is_available_af(info))
-                        break;
-                ret = m5mols_read_u8(sd, AF_STATUS, &reg);
-                v4l2_dbg(2, m5mols_debug, sd, "AF %s\n",
-                         reg == REG_AF_FAIL ? "Failed" :
-                         reg == REG_AF_SUCCESS ? "Success" :
-                         reg == REG_AF_IDLE ? "Idle" : "Busy");
-                break;
-        case REG_INT_CAPTURE:
-                if (!test_and_set_bit(ST_CAPT_IRQ, &info->flags))
-                        wake_up_interruptible(&info->irq_waitq);
-
-                v4l2_dbg(2, m5mols_debug, sd, "CAPTURE\n");
-                break;
-        default:
-                v4l2_dbg(2, m5mols_debug, sd, "Undefined: %02x\n", reg);
-                break;
-        };
-}
-
 static irqreturn_t m5mols_irq_handler(int irq, void *data)
 {
-        struct v4l2_subdev *sd = data;
-        struct m5mols_info *info = to_m5mols(sd);
+        struct m5mols_info *info = to_m5mols(data);
 
-        schedule_work(&info->work_irq);
+        atomic_set(&info->irq_done, 1);
+        wake_up_interruptible(&info->irq_waitq);
 
         return IRQ_HANDLED;
 }
@@ -987,7 +967,6 @@ static int __devinit m5mols_probe(struct i2c_client *client,
         sd->entity.type = MEDIA_ENT_T_V4L2_SUBDEV_SENSOR;
 
         init_waitqueue_head(&info->irq_waitq);
-        INIT_WORK(&info->work_irq, m5mols_irq_work);
         ret = request_irq(client->irq, m5mols_irq_handler,
                           IRQF_TRIGGER_RISING, MODULE_NAME, sd);
         if (ret) {
@@ -995,6 +974,7 @@ static int __devinit m5mols_probe(struct i2c_client *client,
                 goto out_me;
         }
         info->res_type = M5MOLS_RESTYPE_MONITOR;
+
         return 0;
 out_me:
         media_entity_cleanup(&sd->entity);