diff mbox series

docs: remove the 2.6 "Upgrading I2C Drivers" guide

Message ID 20200805183149.21647-1-steve@sk2.org
State Superseded
Headers show
Series docs: remove the 2.6 "Upgrading I2C Drivers" guide | expand

Commit Message

Stephen Kitt Aug. 5, 2020, 6:31 p.m. UTC
All the drivers have long since been upgraded, and all the important
information here is also included in the "Implementing I2C device
drivers" guide.

Signed-off-by: Stephen Kitt <steve@sk2.org>
---
 Documentation/i2c/upgrading-clients.rst | 285 ------------------------
 1 file changed, 285 deletions(-)
 delete mode 100644 Documentation/i2c/upgrading-clients.rst


base-commit: 2324d50d051ec0f14a548e78554fb02513d6dcef

Comments

Wolfram Sang Aug. 5, 2020, 9:53 p.m. UTC | #1
Hi Stephen,

On Wed, Aug 05, 2020 at 08:31:49PM +0200, Stephen Kitt wrote:
> All the drivers have long since been upgraded, and all the important
> information here is also included in the "Implementing I2C device
> drivers" guide.
> 
> Signed-off-by: Stephen Kitt <steve@sk2.org>

True! Thanks.

But I can't apply the patch?

> base-commit: 2324d50d051ec0f14a548e78554fb02513d6dcef

Maybe because I don't have the commit in my tree? Can you rebase on top
of 5.8?

And please also remove the reference in Documentation/i2c/index.rst

Kind regards,

   Wolfram
Stephen Kitt Aug. 6, 2020, 7:09 a.m. UTC | #2
Hi Wolfram,

On Wed, 5 Aug 2020 23:53:51 +0200, Wolfram Sang <wsa@kernel.org> wrote:
> On Wed, Aug 05, 2020 at 08:31:49PM +0200, Stephen Kitt wrote:
> > All the drivers have long since been upgraded, and all the important
> > information here is also included in the "Implementing I2C device
> > drivers" guide.
> > 
> > Signed-off-by: Stephen Kitt <steve@sk2.org>  
> 
> True! Thanks.
> 
> But I can't apply the patch?
> 
> > base-commit: 2324d50d051ec0f14a548e78554fb02513d6dcef  
> 
> Maybe because I don't have the commit in my tree? Can you rebase on top
> of 5.8?

Ah, yes, the commit is on top of Linus’ current master, following the merge
of docs-5.9 from Jon’s tree. In 5.8 the file is a .txt file, but Mauro
converted it to .rst for 5.9, and this patch removes the latter file (to
avoid a merge conflict later on...). If you prefer, I can submit it to the
docs tree instead!

> And please also remove the reference in Documentation/i2c/index.rst

Oops, yes, I’ll do that in v2 once we decide where it should go.

Regards,

Stephen
Wolfram Sang Aug. 6, 2020, 8:33 a.m. UTC | #3
> > Maybe because I don't have the commit in my tree? Can you rebase on top
> > of 5.8?
> 
> Ah, yes, the commit is on top of Linus’ current master, following the merge
> of docs-5.9 from Jon’s tree. In 5.8 the file is a .txt file, but Mauro
> converted it to .rst for 5.9, and this patch removes the latter file (to
> avoid a merge conflict later on...). If you prefer, I can submit it to the
> docs tree instead!

I see. Thanks for the heads up!

> > And please also remove the reference in Documentation/i2c/index.rst
> 
> Oops, yes, I’ll do that in v2 once we decide where it should go.

I am fine with either it going via the doc-tree or you sending me v2
again after 5.9-rc1. For the first case:

Acked-by: Wolfram Sang <wsa@kernel.org>
Stephen Kitt Aug. 6, 2020, 4:13 p.m. UTC | #4
Hi Jon,

You’ll see v2 of this patch show up soon, see the context below — this is a
patch on top of Mauro’s conversion of the i2c docs to .rst.

Regards,

Stephen


On Thu, 6 Aug 2020 10:33:56 +0200, Wolfram Sang <wsa@the-dreams.de> wrote:

> > > Maybe because I don't have the commit in my tree? Can you rebase on top
> > > of 5.8?  
> > 
> > Ah, yes, the commit is on top of Linus’ current master, following the
> > merge of docs-5.9 from Jon’s tree. In 5.8 the file is a .txt file, but
> > Mauro converted it to .rst for 5.9, and this patch removes the latter
> > file (to avoid a merge conflict later on...). If you prefer, I can submit
> > it to the docs tree instead!  
> 
> I see. Thanks for the heads up!
> 
> > > And please also remove the reference in Documentation/i2c/index.rst  
> > 
> > Oops, yes, I’ll do that in v2 once we decide where it should go.  
> 
> I am fine with either it going via the doc-tree or you sending me v2
> again after 5.9-rc1. For the first case:
> 
> Acked-by: Wolfram Sang <wsa@kernel.org>
>
diff mbox series

Patch

diff --git a/Documentation/i2c/upgrading-clients.rst b/Documentation/i2c/upgrading-clients.rst
deleted file mode 100644
index 1708090d7b8f..000000000000
--- a/Documentation/i2c/upgrading-clients.rst
+++ /dev/null
@@ -1,285 +0,0 @@ 
-=================================================
-Upgrading I2C Drivers to the new 2.6 Driver Model
-=================================================
-
-Ben Dooks <ben-linux@fluff.org>
-
-Introduction
-------------
-
-This guide outlines how to alter existing Linux 2.6 client drivers from
-the old to the new binding methods.
-
-
-Example old-style driver
-------------------------
-
-::
-
-  struct example_state {
-	struct i2c_client	client;
-	....
-  };
-
-  static struct i2c_driver example_driver;
-
-  static unsigned short ignore[] = { I2C_CLIENT_END };
-  static unsigned short normal_addr[] = { OUR_ADDR, I2C_CLIENT_END };
-
-  I2C_CLIENT_INSMOD;
-
-  static int example_attach(struct i2c_adapter *adap, int addr, int kind)
-  {
-	struct example_state *state;
-	struct device *dev = &adap->dev;  /* to use for dev_ reports */
-	int ret;
-
-	state = kzalloc(sizeof(struct example_state), GFP_KERNEL);
-	if (state == NULL) {
-		dev_err(dev, "failed to create our state\n");
-		return -ENOMEM;
-	}
-
-	example->client.addr    = addr;
-	example->client.flags   = 0;
-	example->client.adapter = adap;
-
-	i2c_set_clientdata(&state->i2c_client, state);
-	strscpy(client->i2c_client.name, "example", sizeof(client->i2c_client.name));
-
-	ret = i2c_attach_client(&state->i2c_client);
-	if (ret < 0) {
-		dev_err(dev, "failed to attach client\n");
-		kfree(state);
-		return ret;
-	}
-
-	dev = &state->i2c_client.dev;
-
-	/* rest of the initialisation goes here. */
-
-	dev_info(dev, "example client created\n");
-
-	return 0;
-  }
-
-  static int example_detach(struct i2c_client *client)
-  {
-	struct example_state *state = i2c_get_clientdata(client);
-
-	i2c_detach_client(client);
-	kfree(state);
-	return 0;
-  }
-
-  static int example_attach_adapter(struct i2c_adapter *adap)
-  {
-	return i2c_probe(adap, &addr_data, example_attach);
-  }
-
-  static struct i2c_driver example_driver = {
-	.driver		= {
-		.owner		= THIS_MODULE,
-		.name		= "example",
-		.pm		= &example_pm_ops,
-	},
-	.attach_adapter = example_attach_adapter,
-	.detach_client	= example_detach,
-  };
-
-
-Updating the client
--------------------
-
-The new style binding model will check against a list of supported
-devices and their associated address supplied by the code registering
-the busses. This means that the driver .attach_adapter and
-.detach_client methods can be removed, along with the addr_data,
-as follows::
-
-  - static struct i2c_driver example_driver;
-
-  - static unsigned short ignore[] = { I2C_CLIENT_END };
-  - static unsigned short normal_addr[] = { OUR_ADDR, I2C_CLIENT_END };
-
-  - I2C_CLIENT_INSMOD;
-
-  - static int example_attach_adapter(struct i2c_adapter *adap)
-  - {
-  - 	return i2c_probe(adap, &addr_data, example_attach);
-  - }
-
-    static struct i2c_driver example_driver = {
-  -	.attach_adapter = example_attach_adapter,
-  -	.detach_client	= example_detach,
-    }
-
-Add the probe and remove methods to the i2c_driver, as so::
-
-   static struct i2c_driver example_driver = {
-  +	.probe		= example_probe,
-  +	.remove		= example_remove,
-   }
-
-Change the example_attach method to accept the new parameters
-which include the i2c_client that it will be working with::
-
-  - static int example_attach(struct i2c_adapter *adap, int addr, int kind)
-  + static int example_probe(struct i2c_client *client,
-  +			   const struct i2c_device_id *id)
-
-Change the name of example_attach to example_probe to align it with the
-i2c_driver entry names. The rest of the probe routine will now need to be
-changed as the i2c_client has already been setup for use.
-
-The necessary client fields have already been setup before
-the probe function is called, so the following client setup
-can be removed::
-
-  -	example->client.addr    = addr;
-  -	example->client.flags   = 0;
-  -	example->client.adapter = adap;
-  -
-  -	strscpy(client->i2c_client.name, "example", sizeof(client->i2c_client.name));
-
-The i2c_set_clientdata is now::
-
-  -	i2c_set_clientdata(&state->client, state);
-  +	i2c_set_clientdata(client, state);
-
-The call to i2c_attach_client is no longer needed, if the probe
-routine exits successfully, then the driver will be automatically
-attached by the core. Change the probe routine as so::
-
-  -	ret = i2c_attach_client(&state->i2c_client);
-  -	if (ret < 0) {
-  -		dev_err(dev, "failed to attach client\n");
-  -		kfree(state);
-  -		return ret;
-  -	}
-
-
-Remove the storage of 'struct i2c_client' from the 'struct example_state'
-as we are provided with the i2c_client in our example_probe. Instead we
-store a pointer to it for when it is needed.
-
-::
-
-  struct example_state {
-  -	struct i2c_client	client;
-  +	struct i2c_client	*client;
-
-the new i2c client as so::
-
-  -	struct device *dev = &adap->dev;  /* to use for dev_ reports */
-  + 	struct device *dev = &i2c_client->dev;  /* to use for dev_ reports */
-
-And remove the change after our client is attached, as the driver no
-longer needs to register a new client structure with the core::
-
-  -	dev = &state->i2c_client.dev;
-
-In the probe routine, ensure that the new state has the client stored
-in it::
-
-  static int example_probe(struct i2c_client *i2c_client,
-			 const struct i2c_device_id *id)
-  {
-	struct example_state *state;
-	struct device *dev = &i2c_client->dev;
-	int ret;
-
-	state = kzalloc(sizeof(struct example_state), GFP_KERNEL);
-	if (state == NULL) {
-		dev_err(dev, "failed to create our state\n");
-		return -ENOMEM;
-	}
-
-  +	state->client = i2c_client;
-
-Update the detach method, by changing the name to _remove and
-to delete the i2c_detach_client call. It is possible that you
-can also remove the ret variable as it is not needed for any
-of the core functions.
-
-::
-
-  - static int example_detach(struct i2c_client *client)
-  + static int example_remove(struct i2c_client *client)
-  {
-	struct example_state *state = i2c_get_clientdata(client);
-
-  -	i2c_detach_client(client);
-
-And finally ensure that we have the correct ID table for the i2c-core
-and other utilities::
-
-  + struct i2c_device_id example_idtable[] = {
-  +       { "example", 0 },
-  +       { }
-  +};
-  +
-  +MODULE_DEVICE_TABLE(i2c, example_idtable);
-
-  static struct i2c_driver example_driver = {
-	.driver		= {
-		.owner		= THIS_MODULE,
-		.name		= "example",
-	},
-  +	.id_table	= example_ids,
-
-
-Our driver should now look like this::
-
-  struct example_state {
-	struct i2c_client	*client;
-	....
-  };
-
-  static int example_probe(struct i2c_client *client,
-			 const struct i2c_device_id *id)
-  {
-	struct example_state *state;
-	struct device *dev = &client->dev;
-
-	state = kzalloc(sizeof(struct example_state), GFP_KERNEL);
-	if (state == NULL) {
-		dev_err(dev, "failed to create our state\n");
-		return -ENOMEM;
-	}
-
-	state->client = client;
-	i2c_set_clientdata(client, state);
-
-	/* rest of the initialisation goes here. */
-
-	dev_info(dev, "example client created\n");
-
-	return 0;
-  }
-
-  static int example_remove(struct i2c_client *client)
-  {
-	struct example_state *state = i2c_get_clientdata(client);
-
-	kfree(state);
-	return 0;
-  }
-
-  static struct i2c_device_id example_idtable[] = {
-	{ "example", 0 },
-	{ }
-  };
-
-  MODULE_DEVICE_TABLE(i2c, example_idtable);
-
-  static struct i2c_driver example_driver = {
-	.driver		= {
-		.owner		= THIS_MODULE,
-		.name		= "example",
-		.pm		= &example_pm_ops,
-	},
-	.id_table	= example_idtable,
-	.probe		= example_probe,
-	.remove		= example_remove,
-  };