[Linux-kernel-mentees] [PATCH 0/1] Implement a DVB Dummy Tuner

[Linux-kernel-mentees] [PATCH 0/1] Implement a DVB Dummy Tuner

[Daniel W. S. Almeida]

From: "Daniel W. S. Almeida" <dwlsalmeida@gmail.com>

This patch series should implement a dummy DVB tuner as part of ongoing work
on a virtual DVB test driver under the 2020 Spring Linux Kernel Mentorship Program.

as 
Daniel W. S. Almeida (1):
  media: dvb_dummy_tuner: implement driver skeleton

 drivers/media/tuners/Kconfig           |   7 ++
 drivers/media/tuners/Makefile          |   1 +
 drivers/media/tuners/dvb_dummy_tuner.c | 153 +++++++++++++++++++++++++
 drivers/media/tuners/dvb_dummy_tuner.h |  20 ++++
 4 files changed, 181 insertions(+)
 create mode 100644 drivers/media/tuners/dvb_dummy_tuner.c
 create mode 100644 drivers/media/tuners/dvb_dummy_tuner.h

-- 
2.24.1

_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees

[Linux-kernel-mentees] [PATCH 1/1] media: dvb_dummy_tuner: implement driver skeleton

[Daniel W. S. Almeida]

From: "Daniel W. S. Almeida" <dwlsalmeida@gmail.com>

Implement the skeleton for the tuner driver in a separate file.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
---
 drivers/media/tuners/Kconfig           |   7 ++
 drivers/media/tuners/Makefile          |   1 +
 drivers/media/tuners/dvb_dummy_tuner.c | 153 +++++++++++++++++++++++++
 drivers/media/tuners/dvb_dummy_tuner.h |  20 ++++
 4 files changed, 181 insertions(+)
 create mode 100644 drivers/media/tuners/dvb_dummy_tuner.c
 create mode 100644 drivers/media/tuners/dvb_dummy_tuner.h

diff --git a/drivers/media/tuners/Kconfig b/drivers/media/tuners/Kconfig
index e104bb7766e1..efa1591fe0ae 100644
--- a/drivers/media/tuners/Kconfig
+++ b/drivers/media/tuners/Kconfig
@@ -296,4 +296,11 @@ config MEDIA_TUNER_QM1D1B0004
 	default m if !MEDIA_SUBDRV_AUTOSELECT
 	help
 	  Sharp QM1D1B0004 ISDB-S tuner driver.
+
+config MEDIA_TUNER_DVB_DUMMY_TUNER
+	tristate "Dummy tuner"
+	depends on MEDIA_SUPPORT && I2C
+	default m if !MEDIA_SUBDRV_AUTOSELECT
+	help
+	  Dummy tuner driver for common TV standards.
 endmenu
diff --git a/drivers/media/tuners/Makefile b/drivers/media/tuners/Makefile
index 7b4f8423501e..f98de1cf2e19 100644
--- a/drivers/media/tuners/Makefile
+++ b/drivers/media/tuners/Makefile
@@ -44,5 +44,6 @@ obj-$(CONFIG_MEDIA_TUNER_QM1D1C0042) += qm1d1c0042.o
 obj-$(CONFIG_MEDIA_TUNER_QM1D1B0004) += qm1d1b0004.o
 obj-$(CONFIG_MEDIA_TUNER_M88RS6000T) += m88rs6000t.o
 obj-$(CONFIG_MEDIA_TUNER_TDA18250) += tda18250.o
+obj-$(CONFIG_MEDIA_TUNER_DVB_DUMMY_TUNER) += dvb_dummy_tuner.o
 
 ccflags-y += -I$(srctree)/drivers/media/dvb-frontends
diff --git a/drivers/media/tuners/dvb_dummy_tuner.c b/drivers/media/tuners/dvb_dummy_tuner.c
new file mode 100644
index 000000000000..63d2e47d4739
--- /dev/null
+++ b/drivers/media/tuners/dvb_dummy_tuner.c
@@ -0,0 +1,153 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  Driver for Dummy Frontend
+ *
+ *  Written by Daniel W. S. Almeida <dwlsalmeida@gmail.com>
+ */
+
+#include <linux/errno.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <media/dvb_frontend.h>
+#include "dvb_dummy_tuner.h"
+
+struct dvb_dummy_tuner_dev {
+	struct dvb_frontend *fe;
+};
+
+static void dvb_dummy_tuner_release(struct dvb_frontend *fe)
+{
+}
+
+static int dvb_dummy_tuner_init(struct dvb_frontend *fe)
+{
+	return 0;
+}
+
+static int dvb_dummy_tuner_sleep(struct dvb_frontend *fe)
+{
+	return 0;
+}
+
+static int dvb_dummy_tuner_suspend(struct dvb_frontend *fe)
+{
+	return 0;
+}
+
+static int dvb_dummy_tuner_resume(struct dvb_frontend *fe)
+{
+	return 0;
+}
+
+static int dvb_dummy_tuner_set_params(struct dvb_frontend *fe)
+{
+	return 0;
+}
+
+static int dvb_dummy_tuner_set_config(struct dvb_frontend *fe, void *priv_cfg)
+{
+	return 0;
+}
+
+static int dvb_dummy_tuner_get_frequency(struct dvb_frontend *fe,
+					 u32 *frequency)
+{
+	return 0;
+}
+
+static int dvb_dummy_tuner_get_bandwidth(struct dvb_frontend *fe,
+					 u32 *bandwidth)
+{
+	return 0;
+}
+
+static int dvb_dummy_tuner_get_if_frequency(struct dvb_frontend *fe,
+					    u32 *frequency)
+{
+	return 0;
+}
+
+static int dvb_dummy_tuner_get_status(struct dvb_frontend *fe, u32 *status)
+{
+	return 0;
+}
+
+static const struct dvb_tuner_ops dvb_dummy_tuner_ops = {
+	.release = dvb_dummy_tuner_release,
+	.init = dvb_dummy_tuner_init,
+	.sleep = dvb_dummy_tuner_sleep,
+	.suspend = dvb_dummy_tuner_suspend,
+	.resume = dvb_dummy_tuner_resume,
+	.set_params = dvb_dummy_tuner_set_params,
+	.set_config = dvb_dummy_tuner_set_config,
+	.get_bandwidth = dvb_dummy_tuner_get_bandwidth,
+	.get_frequency = dvb_dummy_tuner_get_frequency,
+	.get_if_frequency = dvb_dummy_tuner_get_if_frequency,
+	.get_status = dvb_dummy_tuner_get_status,
+};
+
+static const struct i2c_device_id dvb_dummy_tuner_i2c_id_table[] = {
+	{"dvb_dummy_tuner", 0},
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, dvb_dummy_tuner_i2c_id_table);
+
+static int dvb_dummy_tuner_i2c_probe(struct i2c_client *client,
+				     const struct i2c_device_id *id)
+{
+	int ret = 0;
+	struct dvb_dummy_tuner_config *config = client->dev.platform_data;
+	struct dvb_frontend *fe = config->fe;
+	struct dvb_dummy_tuner_dev *tuner_dev = NULL;
+
+	tuner_dev = kzalloc(sizeof(*tuner_dev), GFP_KERNEL);
+	if (!tuner_dev) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	i2c_set_clientdata(client, tuner_dev);
+	tuner_dev->fe = config->fe;
+
+	memcpy(&fe->ops.tuner_ops,
+	       &dvb_dummy_tuner_ops,
+	       sizeof(struct dvb_tuner_ops));
+
+	fe->tuner_priv = client;
+
+	pr_debug("%s: Successfully probed %s\n", __func__, client->name);
+	return ret;
+
+err:
+	pr_err("%s: failed\n", __func__);
+	return ret;
+}
+
+static int dvb_dummy_tuner_i2c_remove(struct i2c_client *client)
+{
+	struct dvb_dummy_tuner_dev *tuner_dev = i2c_get_clientdata(client);
+	struct dvb_frontend *fe = tuner_dev->fe;
+
+	memset(&fe->ops.tuner_ops, 0, sizeof(struct dvb_tuner_ops));
+	fe->tuner_priv = NULL;
+	kfree(tuner_dev);
+
+	return 0;
+}
+
+static struct i2c_driver dvb_dummy_tuner_i2c_driver = {
+	.driver = {
+		.name = "dvb_dummy_tuner",
+		.suppress_bind_attrs = true,
+	},
+	.probe		= dvb_dummy_tuner_i2c_probe,
+	.remove		= dvb_dummy_tuner_i2c_remove,
+	.id_table	= dvb_dummy_tuner_i2c_id_table,
+};
+module_i2c_driver(dvb_dummy_tuner_i2c_driver);
+
+MODULE_DESCRIPTION("DVB Dummy Tuner");
+MODULE_AUTHOR("Daniel W. S. Almeida");
+MODULE_LICENSE("GPL");
diff --git a/drivers/media/tuners/dvb_dummy_tuner.h b/drivers/media/tuners/dvb_dummy_tuner.h
new file mode 100644
index 000000000000..fde7628258fa
--- /dev/null
+++ b/drivers/media/tuners/dvb_dummy_tuner.h
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * DVB Dummy Tuner
+ *
+ */
+#ifndef __TUNER_DVB_DUMMY_TUNER_H__
+#define __TUNER_DVB_DUMMY_TUNER_H__
+
+#include <media/dvb_frontend.h>
+/**
+ * struct dvb_dummy_tuner_config - configuration parameters for the dummy tuner
+ *
+ * @fe:
+ *	frontend returned by driver
+ */
+struct dvb_dummy_tuner_config {
+	struct dvb_frontend *fe;
+};
+
+#endif /*__TUNER_DVB_DUMMY_TUNER_H__ */
-- 
2.24.1

_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees

Re: [Linux-kernel-mentees] [PATCH 1/1] media: dvb_dummy_tuner: implement driver skeleton

[Greg KH]

On Thu, Jan 09, 2020 at 12:24:08PM -0300, Daniel W. S. Almeida wrote:
> +static int dvb_dummy_tuner_i2c_probe(struct i2c_client *client,
> +				     const struct i2c_device_id *id)
> +{
> +	int ret = 0;
> +	struct dvb_dummy_tuner_config *config = client->dev.platform_data;
> +	struct dvb_frontend *fe = config->fe;
> +	struct dvb_dummy_tuner_dev *tuner_dev = NULL;
> +
> +	tuner_dev = kzalloc(sizeof(*tuner_dev), GFP_KERNEL);
> +	if (!tuner_dev) {
> +		ret = -ENOMEM;
> +		goto err;
> +	}
> +
> +	i2c_set_clientdata(client, tuner_dev);
> +	tuner_dev->fe = config->fe;
> +
> +	memcpy(&fe->ops.tuner_ops,
> +	       &dvb_dummy_tuner_ops,
> +	       sizeof(struct dvb_tuner_ops));
> +
> +	fe->tuner_priv = client;
> +
> +	pr_debug("%s: Successfully probed %s\n", __func__, client->name);

As you are a driver, you should never need to call any pr_* calls,
instead use dev_*().  For this, you can use dev_dbg(), but really, why
is that even needed except for your debugging bringup.  And for that,
you can use ftrace, right?  So no need for any printing of anything
here.

> +	return ret;
> +
> +err:
> +	pr_err("%s: failed\n", __func__);

Again, dev_err() would be proper, but there's no need for any error
message here.


Don't you need to register the tuner ops with something in this
function?

> +	return ret;
> +}
> +
> +static int dvb_dummy_tuner_i2c_remove(struct i2c_client *client)
> +{
> +	struct dvb_dummy_tuner_dev *tuner_dev = i2c_get_clientdata(client);
> +	struct dvb_frontend *fe = tuner_dev->fe;
> +
> +	memset(&fe->ops.tuner_ops, 0, sizeof(struct dvb_tuner_ops));
> +	fe->tuner_priv = NULL;
> +	kfree(tuner_dev);
> +

Don't you need to unregister the tuner ops in here?

thanks,

greg k-h
_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees

Re: [Linux-kernel-mentees] [PATCH 0/1] Implement a DVB Dummy Tuner

[Mauro Carvalho Chehab]

Em Thu,  9 Jan 2020 12:24:07 -0300
"Daniel W. S. Almeida" <dwlsalmeida@gmail.com> escreveu:

> From: "Daniel W. S. Almeida" <dwlsalmeida@gmail.com>
> 
> This patch series should implement a dummy DVB tuner as part of ongoing work
> on a virtual DVB test driver under the 2020 Spring Linux Kernel Mentorship Program.

No need for a patch 0/1. If you want to send just one patch, just sent it
directly as:

	[PATCH] foo

> 
> as 
> Daniel W. S. Almeida (1):
>   media: dvb_dummy_tuner: implement driver skeleton
> 
>  drivers/media/tuners/Kconfig           |   7 ++
>  drivers/media/tuners/Makefile          |   1 +
>  drivers/media/tuners/dvb_dummy_tuner.c | 153 +++++++++++++++++++++++++
>  drivers/media/tuners/dvb_dummy_tuner.h |  20 ++++
>  4 files changed, 181 insertions(+)
>  create mode 100644 drivers/media/tuners/dvb_dummy_tuner.c
>  create mode 100644 drivers/media/tuners/dvb_dummy_tuner.h
> 




Cheers,
Mauro
_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees

Re: [Linux-kernel-mentees] [PATCH 1/1] media: dvb_dummy_tuner: implement driver skeleton

[Mauro Carvalho Chehab]

Em Thu,  9 Jan 2020 12:24:08 -0300
"Daniel W. S. Almeida" <dwlsalmeida@gmail.com> escreveu:

> From: "Daniel W. S. Almeida" <dwlsalmeida@gmail.com>
> 
> Implement the skeleton for the tuner driver in a separate file.
> 
> Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
> ---
>  drivers/media/tuners/Kconfig           |   7 ++
>  drivers/media/tuners/Makefile          |   1 +
>  drivers/media/tuners/dvb_dummy_tuner.c | 153 +++++++++++++++++++++++++
>  drivers/media/tuners/dvb_dummy_tuner.h |  20 ++++
>  4 files changed, 181 insertions(+)
>  create mode 100644 drivers/media/tuners/dvb_dummy_tuner.c
>  create mode 100644 drivers/media/tuners/dvb_dummy_tuner.h
> 
> diff --git a/drivers/media/tuners/Kconfig b/drivers/media/tuners/Kconfig
> index e104bb7766e1..efa1591fe0ae 100644
> --- a/drivers/media/tuners/Kconfig
> +++ b/drivers/media/tuners/Kconfig
> @@ -296,4 +296,11 @@ config MEDIA_TUNER_QM1D1B0004
>  	default m if !MEDIA_SUBDRV_AUTOSELECT
>  	help
>  	  Sharp QM1D1B0004 ISDB-S tuner driver.
> +
> +config MEDIA_TUNER_DVB_DUMMY_TUNER
> +	tristate "Dummy tuner"
> +	depends on MEDIA_SUPPORT && I2C

> +	default m if !MEDIA_SUBDRV_AUTOSELECT

Actually, this is a dummy driver. It should not be auto-selected, as no
real hardware depends on it. We don't want production distros to come with
those test drivers.

When we add a bridge driver (let's say we call it DVB_DUMMY_BRIDGE), then
what we could do here would be something like:

	depends on DVB_DUMMY_BRIDGE
	default y

Cheers,
Mauro
_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees

Re: [Linux-kernel-mentees] [PATCH 1/1] media: dvb_dummy_tuner: implement driver skeleton

[Shuah Khan]

Hi Daniel,

On 1/9/20 8:24 AM, Daniel W. S. Almeida wrote:
> From: "Daniel W. S. Almeida" <dwlsalmeida@gmail.com>
> 
> Implement the skeleton for the tuner driver in a separate file.

Please add more detail here on what this driver does. What this
driver is used for and so on.

> 
> Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
> ---
>   drivers/media/tuners/Kconfig           |   7 ++
>   drivers/media/tuners/Makefile          |   1 +
>   drivers/media/tuners/dvb_dummy_tuner.c | 153 +++++++++++++++++++++++++
>   drivers/media/tuners/dvb_dummy_tuner.h |  20 ++++
>   4 files changed, 181 insertions(+)
>   create mode 100644 drivers/media/tuners/dvb_dummy_tuner.c
>   create mode 100644 drivers/media/tuners/dvb_dummy_tuner.h
> 
> diff --git a/drivers/media/tuners/Kconfig b/drivers/media/tuners/Kconfig
> index e104bb7766e1..efa1591fe0ae 100644
> --- a/drivers/media/tuners/Kconfig
> +++ b/drivers/media/tuners/Kconfig
> @@ -296,4 +296,11 @@ config MEDIA_TUNER_QM1D1B0004
>   	default m if !MEDIA_SUBDRV_AUTOSELECT
>   	help
>   	  Sharp QM1D1B0004 ISDB-S tuner driver.
> +
> +config MEDIA_TUNER_DVB_DUMMY_TUNER
> +	tristate "Dummy tuner"
> +	depends on MEDIA_SUPPORT && I2C
> +	default m if !MEDIA_SUBDRV_AUTOSELECT
> +	help
> +	  Dummy tuner driver for common TV standards.

Samehere. Give more details on what this driver does. Add enough detail
to help users decide why they should enable it or not.

>   endmenu
> diff --git a/drivers/media/tuners/Makefile b/drivers/media/tuners/Makefile
> index 7b4f8423501e..f98de1cf2e19 100644
> --- a/drivers/media/tuners/Makefile
> +++ b/drivers/media/tuners/Makefile
> @@ -44,5 +44,6 @@ obj-$(CONFIG_MEDIA_TUNER_QM1D1C0042) += qm1d1c0042.o
>   obj-$(CONFIG_MEDIA_TUNER_QM1D1B0004) += qm1d1b0004.o
>   obj-$(CONFIG_MEDIA_TUNER_M88RS6000T) += m88rs6000t.o
>   obj-$(CONFIG_MEDIA_TUNER_TDA18250) += tda18250.o
> +obj-$(CONFIG_MEDIA_TUNER_DVB_DUMMY_TUNER) += dvb_dummy_tuner.o
>   
>   ccflags-y += -I$(srctree)/drivers/media/dvb-frontends
> diff --git a/drivers/media/tuners/dvb_dummy_tuner.c b/drivers/media/tuners/dvb_dummy_tuner.c
> new file mode 100644
> index 000000000000..63d2e47d4739
> --- /dev/null
> +++ b/drivers/media/tuners/dvb_dummy_tuner.c
> @@ -0,0 +1,153 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + *  Driver for Dummy Frontend
> + *
> + *  Written by Daniel W. S. Almeida <dwlsalmeida@gmail.com>

General practice is the following.

Copyright (c) 2020 Daniel W. S. Almeida <dwlsalmeida@gmail.com>

> + */
> +
> +#include <linux/errno.h>
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/slab.h>
> +#include <linux/types.h>
> +#include <media/dvb_frontend.h>
> +#include "dvb_dummy_tuner.h"
> +
> +struct dvb_dummy_tuner_dev {
> +	struct dvb_frontend *fe;
> +};
> +
> +static void dvb_dummy_tuner_release(struct dvb_frontend *fe)
> +{
> +}
> +
> +static int dvb_dummy_tuner_init(struct dvb_frontend *fe)
> +{
> +	return 0;
> +}
> +
> +static int dvb_dummy_tuner_sleep(struct dvb_frontend *fe)
> +{
> +	return 0;
> +}
> +
> +static int dvb_dummy_tuner_suspend(struct dvb_frontend *fe)
> +{
> +	return 0;
> +}
> +
> +static int dvb_dummy_tuner_resume(struct dvb_frontend *fe)
> +{
> +	return 0;
> +}
> +
> +static int dvb_dummy_tuner_set_params(struct dvb_frontend *fe)
> +{
> +	return 0;
> +}
> +
> +static int dvb_dummy_tuner_set_config(struct dvb_frontend *fe, void *priv_cfg)
> +{
> +	return 0;
> +}
> +
> +static int dvb_dummy_tuner_get_frequency(struct dvb_frontend *fe,
> +					 u32 *frequency)
> +{
> +	return 0;
> +}
> +
> +static int dvb_dummy_tuner_get_bandwidth(struct dvb_frontend *fe,
> +					 u32 *bandwidth)
> +{
> +	return 0;
> +}
> +
> +static int dvb_dummy_tuner_get_if_frequency(struct dvb_frontend *fe,
> +					    u32 *frequency)
> +{
> +	return 0;
> +}
> +
> +static int dvb_dummy_tuner_get_status(struct dvb_frontend *fe, u32 *status)
> +{
> +	return 0;
> +}
> +
> +static const struct dvb_tuner_ops dvb_dummy_tuner_ops = {
> +	.release = dvb_dummy_tuner_release,
> +	.init = dvb_dummy_tuner_init,
> +	.sleep = dvb_dummy_tuner_sleep,
> +	.suspend = dvb_dummy_tuner_suspend,
> +	.resume = dvb_dummy_tuner_resume,
> +	.set_params = dvb_dummy_tuner_set_params,
> +	.set_config = dvb_dummy_tuner_set_config,
> +	.get_bandwidth = dvb_dummy_tuner_get_bandwidth,
> +	.get_frequency = dvb_dummy_tuner_get_frequency,
> +	.get_if_frequency = dvb_dummy_tuner_get_if_frequency,
> +	.get_status = dvb_dummy_tuner_get_status,
> +};
> +
> +static const struct i2c_device_id dvb_dummy_tuner_i2c_id_table[] = {
> +	{"dvb_dummy_tuner", 0},
> +	{}
> +};
> +MODULE_DEVICE_TABLE(i2c, dvb_dummy_tuner_i2c_id_table);
> +
> +static int dvb_dummy_tuner_i2c_probe(struct i2c_client *client,
> +				     const struct i2c_device_id *id)
> +{
> +	int ret = 0;
> +	struct dvb_dummy_tuner_config *config = client->dev.platform_data;
> +	struct dvb_frontend *fe = config->fe;
> +	struct dvb_dummy_tuner_dev *tuner_dev = NULL;
> +
> +	tuner_dev = kzalloc(sizeof(*tuner_dev), GFP_KERNEL);
> +	if (!tuner_dev) {
> +		ret = -ENOMEM;
> +		goto err;
> +	}
> +
> +	i2c_set_clientdata(client, tuner_dev);
> +	tuner_dev->fe = config->fe;
> +
> +	memcpy(&fe->ops.tuner_ops,
> +	       &dvb_dummy_tuner_ops,
> +	       sizeof(struct dvb_tuner_ops));
> +
> +	fe->tuner_priv = client;
> +
> +	pr_debug("%s: Successfully probed %s\n", __func__, client->name);
> +	return ret;
> +
> +err:
> +	pr_err("%s: failed\n", __func__);
> +	return ret;
> +}
> +
> +static int dvb_dummy_tuner_i2c_remove(struct i2c_client *client)
> +{
> +	struct dvb_dummy_tuner_dev *tuner_dev = i2c_get_clientdata(client);
> +	struct dvb_frontend *fe = tuner_dev->fe;
> +
> +	memset(&fe->ops.tuner_ops, 0, sizeof(struct dvb_tuner_ops));
> +	fe->tuner_priv = NULL;
> +	kfree(tuner_dev);
> +
> +	return 0;
> +}
> +
> +static struct i2c_driver dvb_dummy_tuner_i2c_driver = {
> +	.driver = {
> +		.name = "dvb_dummy_tuner",
> +		.suppress_bind_attrs = true,
> +	},
> +	.probe		= dvb_dummy_tuner_i2c_probe,
> +	.remove		= dvb_dummy_tuner_i2c_remove,
> +	.id_table	= dvb_dummy_tuner_i2c_id_table,
> +};
> +module_i2c_driver(dvb_dummy_tuner_i2c_driver);
> +
> +MODULE_DESCRIPTION("DVB Dummy Tuner");
> +MODULE_AUTHOR("Daniel W. S. Almeida");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/media/tuners/dvb_dummy_tuner.h b/drivers/media/tuners/dvb_dummy_tuner.h
> new file mode 100644
> index 000000000000..fde7628258fa
> --- /dev/null
> +++ b/drivers/media/tuners/dvb_dummy_tuner.h
> @@ -0,0 +1,20 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * DVB Dummy Tuner
> + *

Please add details about the driver similar to the .c file.

> + */
> +#ifndef __TUNER_DVB_DUMMY_TUNER_H__
> +#define __TUNER_DVB_DUMMY_TUNER_H__
> +
> +#include <media/dvb_frontend.h>
> +/**
> + * struct dvb_dummy_tuner_config - configuration parameters for the dummy tuner
> + *
> + * @fe:
> + *	frontend returned by driver
> + */
> +struct dvb_dummy_tuner_config {
> +	struct dvb_frontend *fe;
> +};
> +
> +#endif /*__TUNER_DVB_DUMMY_TUNER_H__ */
> 


Looks like there is more code to be added to register/unregister

thanks,
-- Shuah
_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees

Re: [Linux-kernel-mentees] [PATCH 1/1] media: dvb_dummy_tuner: implement driver skeleton

[Daniel W. S. Almeida]

Hi Greg! Thanks for chiming in.


> As you are a driver, you should never need to call any pr_* calls,
> instead use dev_*().  For this, you can use dev_dbg(), but really, why
> is that even needed except for your debugging bringup.  And for that,
> you can use ftrace, right?  So no need for any printing of anything
> here.
> Again, dev_err() would be proper, but there's no need for any error
> message here.

Let's take these out in v2 then.


> Don't you need to register the tuner ops with something in this
> function?
> Don't you need to unregister the tuner ops in here?

It is my understanding that bridge drivers are the ones responsible for 
this. For instance, I don't see this with either xc4000.c, xc5000.c or 
mt2060.c. I could be wrong, though. Maybe Mauro could clarify this?

What I did miss in this patch was an attach function. Let's also add 
this in v2.


Thanks again,

- Daniel.

_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees

Re: [Linux-kernel-mentees] [PATCH 0/1] Implement a DVB Dummy Tuner

[Daniel W. S. Almeida]

Hi Mauro!


> No need for a patch 0/1. If you want to send just one patch, just sent it
> directly as:
>
> 	[PATCH] foo

I planned on adding more commits to this series in v2, v3 and so forth 
so they would be applied in order, since they would be touching the same 
file. Likewise, the changes could be reviewed in a piecemeal fashion 
making it easier for reviewers. Is this not advisable?

Anyway, thanks for the heads up.


- Daniel.


_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees

Re: [Linux-kernel-mentees] [PATCH 1/1] media: dvb_dummy_tuner: implement driver skeleton

[Daniel W. S. Almeida]

Hi Mauro!

> Actually, this is a dummy driver. It should not be auto-selected, as no
> real hardware depends on it. We don't want production distros to come with
> those test drivers.

Let's address this in v2.


Thanks.


_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees

Re: [Linux-kernel-mentees] [PATCH 1/1] media: dvb_dummy_tuner: implement driver skeleton

[Daniel W. S. Almeida]

Hi Shuah, thank you for you input!


>
> Looks like there is more code to be added to register/unregister 

Just to be clear, attach() is missing, but register / unregister belong 
in the bridge driver. Is this correct?


>
> Please add more detail here on what this driver does. What this
> driver is used for and so on.
>
>
> Samehere. Give more details on what this driver does. Add enough detail
> to help users decide why they should enable it or not. 
>
> General practice is the following.
>
> Copyright (c) 2020 Daniel W. S. Almeida <dwlsalmeida@gmail.com>

> Please add details about the driver similar to the .c file. 

OK.


Thanks

- Daniel


_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees

Re: [Linux-kernel-mentees] [PATCH 1/1] media: dvb_dummy_tuner: implement driver skeleton

[Shuah Khan]

On 1/9/20 2:00 PM, Daniel W. S. Almeida wrote:
> Hi Shuah, thank you for you input!
> 
> 
>>
>> Looks like there is more code to be added to register/unregister 
> 
> Just to be clear, attach() is missing, but register / unregister belong 
> in the bridge driver. Is this correct?
> 
> 

Right attach/detach is what I was thinking.

>>
>> Please add more detail here on what this driver does. What this
>> driver is used for and so on.
>>
>>
>> Samehere. Give more details on what this driver does. Add enough detail
>> to help users decide why they should enable it or not.
>> General practice is the following.
>>
>> Copyright (c) 2020 Daniel W. S. Almeida <dwlsalmeida@gmail.com>
> 
>> Please add details about the driver similar to the .c file. 
> 
> OK.
> 

thanks,
-- Shuah
_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees