V4L/DVB (6112): cx25840: use a workqueue to load the firmware
Loading the firmware using the i2c bit-banging code blocks the kernel.
Move the firmware load code into a workqueue so that it plays well with
other processes.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/video/cx25840/cx25840-core.c b/drivers/media/video/cx25840/cx25840-core.c
index ae90d1c..d6f8b3b 100644
--- a/drivers/media/video/cx25840/cx25840-core.c
+++ b/drivers/media/video/cx25840/cx25840-core.c
@@ -179,9 +179,18 @@
cx25840_and_or(client, 0x15b, ~0x1e, 0x10);
}
+static void cx25840_work_handler(struct work_struct *work)
+{
+ struct cx25840_state *state = container_of(work, struct cx25840_state, fw_work);
+ cx25840_loadfw(state->c);
+ wake_up(&state->fw_wait);
+}
+
static void cx25840_initialize(struct i2c_client *client)
{
+ DEFINE_WAIT(wait);
struct cx25840_state *state = i2c_get_clientdata(client);
+ struct workqueue_struct *q;
/* datasheet startup in numbered steps, refer to page 3-77 */
/* 2. */
@@ -197,7 +206,19 @@
cx25840_write(client, 0x13c, 0x01);
cx25840_write(client, 0x13c, 0x00);
/* 5. */
- cx25840_loadfw(client);
+ /* Do the firmware load in a work handler to prevent.
+ Otherwise the kernel is blocked waiting for the
+ bit-banging i2c interface to finish uploading the
+ firmware. */
+ INIT_WORK(&state->fw_work, cx25840_work_handler);
+ init_waitqueue_head(&state->fw_wait);
+ q = create_singlethread_workqueue("cx25840_fw");
+ prepare_to_wait(&state->fw_wait, &wait, TASK_UNINTERRUPTIBLE);
+ queue_work(q, &state->fw_work);
+ schedule();
+ finish_wait(&state->fw_wait, &wait);
+ destroy_workqueue(q);
+
/* 6. */
cx25840_write(client, 0x115, 0x8c);
cx25840_write(client, 0x116, 0x07);
@@ -872,17 +893,16 @@
if (!i2c_check_functionality(adapter, I2C_FUNC_I2C))
return 0;
- state = kzalloc(sizeof(struct cx25840_state), GFP_KERNEL);
- if (state == 0)
+ client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL);
+ if (client == 0)
return -ENOMEM;
- client = &state->c;
client->addr = address;
client->adapter = adapter;
client->driver = &i2c_driver_cx25840;
snprintf(client->name, sizeof(client->name) - 1, "cx25840");
- v4l_dbg(1, cx25840_debug, client, "detecting cx25840 client on address 0x%x\n", address << 1);
+ v4l_dbg(1, cx25840_debug, client, "detecting cx25840 client on address 0x%x\n", client->addr << 1);
device_id = cx25840_read(client, 0x101) << 8;
device_id |= cx25840_read(client, 0x100);
@@ -891,26 +911,32 @@
* 0x83 for the cx2583x and 0x84 for the cx2584x */
if ((device_id & 0xff00) == 0x8300) {
id = V4L2_IDENT_CX25836 + ((device_id >> 4) & 0xf) - 6;
- state->is_cx25836 = 1;
}
else if ((device_id & 0xff00) == 0x8400) {
id = V4L2_IDENT_CX25840 + ((device_id >> 4) & 0xf);
- state->is_cx25836 = 0;
}
else {
v4l_dbg(1, cx25840_debug, client, "cx25840 not found\n");
- kfree(state);
+ kfree(client);
return 0;
}
+ state = kzalloc(sizeof(struct cx25840_state), GFP_KERNEL);
+ if (state == NULL) {
+ kfree(client);
+ return -ENOMEM;
+ }
+
/* Note: revision '(device_id & 0x0f) == 2' was never built. The
marking skips from 0x1 == 22 to 0x3 == 23. */
v4l_info(client, "cx25%3x-2%x found @ 0x%x (%s)\n",
(device_id & 0xfff0) >> 4,
(device_id & 0x0f) < 3 ? (device_id & 0x0f) + 1 : (device_id & 0x0f),
- address << 1, adapter->name);
+ client->addr << 1, client->adapter->name);
i2c_set_clientdata(client, state);
+ state->c = client;
+ state->is_cx25836 = ((device_id & 0xff00) == 0x8300);
state->vid_input = CX25840_COMPOSITE7;
state->aud_input = CX25840_AUDIO8;
state->audclk_freq = 48000;
@@ -944,6 +970,7 @@
}
kfree(state);
+ kfree(client);
return 0;
}
